pulsesequence() { /* Internal variable declarations *************************/ int shapelist90,shapelist180,shapelistIR; double nseg; double seqtime,tau1,tau2,tau3, te1_delay,te2_delay,te3_delay, iti_delay, ti_delay, tr_delay; double kzero; double freq90[MAXNSLICE], freq180[MAXNSLICE], freqIR[MAXNSLICE]; /* Real-time variables used in this sequence **************/ int vpe_ctr = v2; // PE loop counter int vpe_mult = v3; // PE multiplier, ranges from -PE/2 to PE/2 int vms_slices = v4; // Number of slices int vms_ctr = v5; // Slice loop counter int vseg = v6; // Number of ETL segments int vseg_ctr = v7; // Segment counter int vetl = v8; // Echo train length int vetl_ctr = v9; // Echo train loop counter int vssc = v10; // Compressed steady-states int vtrimage = v11; // Counts down from nt, trimage delay when 0 int vacquire = v12; // Argument for setacqvar, to skip steady state acquires int vphase180 = v13; // phase of 180 degree refocusing pulse /* Initialize paramaters **********************************/ init_mri(); /* Load external PE table ********************************/ if (strcmp(petable,"n") && strcmp(petable,"N") && strcmp(petable,"")) { loadtable(petable); } else { abort_message("petable undefined"); } seqtime = 0.0; espmin = 0.0; kzero = getval("kzero"); /* RF Power & Bandwidth Calculations **********************/ init_rf(&p1_rf,p1pat,p1,flip1,rof1,rof2); init_rf(&p2_rf,p2pat,p2,flip2,rof1,rof2); calc_rf(&p1_rf,"tpwr1","tpwr1f"); calc_rf(&p2_rf,"tpwr2","tpwr2f"); /* Initialize gradient structures *************************/ init_readout_butterfly(&ro_grad,"ro",lro,np,sw,gcrushro,tcrushro); init_readout_refocus(&ror_grad,"ror"); init_phase(&pe_grad,"pe",lpe,nv); init_slice(&ss_grad,"ss",thk); /* NOTE assume same band widths for p1 and p2 */ init_slice_butterfly(&ss2_grad,"ss2",thk,gcrush,tcrush); init_slice_refocus(&ssr_grad,"ssr"); /* Gradient calculations **********************************/ calc_readout(&ro_grad,WRITE,"gro","sw","at"); calc_readout_refocus(&ror_grad,&ro_grad,NOWRITE,"gror"); calc_phase(&pe_grad,WRITE,"gpe","tpe"); calc_slice(&ss_grad,&p1_rf,WRITE,"gss"); calc_slice(&ss2_grad,&p1_rf,WRITE,""); calc_slice_refocus(&ssr_grad,&ss_grad,NOWRITE,"gssr"); /* Equalize refocus and PE gradient durations *************/ calc_sim_gradient(&ror_grad,&null_grad,&ssr_grad,0.0,WRITE); /* Create optional prepulse events ************************/ if (sat[0] == 'y') create_satbands(); if (fsat[0] == 'y') create_fatsat(); if (mt[0] == 'y') create_mtc(); if (ir[0] == 'y') { init_rf(&ir_rf,pipat,pi,flipir,rof1,rof2); calc_rf(&ir_rf,"tpwri","tpwrif"); init_slice_butterfly(&ssi_grad,"ssi",thk,gcrushir,tcrushir); calc_slice(&ssi_grad,&ir_rf,WRITE,"gssi"); } /* Set up frequency offset pulse shape list ********/ offsetlist(pss,ss_grad.ssamp, 0,freq90, ns,seqcon[1]); offsetlist(pss,ss2_grad.ssamp,0,freq180,ns,seqcon[1]); offsetlist(pss,ssi_grad.ssamp,0,freqIR, ns,seqcon[1]); shapelist90 = shapelist(p1pat,ss_grad.rfDuration, freq90, ns,0,seqcon[1]); shapelist180 = shapelist(p2pat,ss2_grad.rfDuration,freq180,ns,0,seqcon[1]); shapelistIR = shapelist(pipat,ssi_grad.rfDuration,freqIR, ns,0,seqcon[1]); /* same slice selection gradient and RF pattern used */ if (ss_grad.rfFraction != 0.5) abort_message("ERROR %s: RF pulse must be symmetric (RF fraction = %.2f)", seqfil,ss_grad.rfFraction); if (ro_grad.echoFraction != 1) abort_message("ERROR %s: Echo Fraction must be 1",seqfil); /* Find sum of all events in each half-echo period ********/ tau1 = ss_grad.rfCenterBack + ssr_grad.duration + ss2_grad.rfCenterFront; tau2 = ss2_grad.rfCenterBack + pe_grad.duration + ro_grad.timeToEcho; tau3 = ro_grad.timeFromEcho + pe_grad.duration + ss2_grad.rfCenterFront; espmin = 2*MAX(MAX(tau1,tau2),tau3); // Minimum echo spacing if (minesp[0] == 'y') { esp = espmin + 8e-6; // ensure at least 4us delays in both TE periods putvalue("esp",esp); } else if (((espmin+8e-6)-esp) > 12.5e-9) { abort_message("ERROR %s: Echo spacing too small, minimum is %.2fms\n",seqfil,(espmin+8e-6)*1000); } te1_delay = esp/2.0 - tau1; // Intra-esp delays te2_delay = esp/2.0 - tau2; te3_delay = esp/2.0 - tau3; te = kzero*esp; // Return effective TE putvalue("te",te); /* Minimum TR **************************************/ /* seqtime is total time per slice */ seqtime = 2*4e-6 + ss_grad.rfCenterFront + etl*esp + ro_grad.timeFromEcho + pe_grad.duration + te3_delay; /* Increase TR if any options are selected****************/ if (sat[0] == 'y') seqtime += ns*satTime; if (fsat[0] == 'y') seqtime += ns*fsatTime; if (mt[0] == 'y') seqtime += ns*mtTime; if (ir[0] == 'y') { /* Inter-IR delay */ if (ns > 1) iti_delay = seqtime - ssi_grad.duration; /* it is probably safe to assume that seqtime is always > the pulse widths */ else iti_delay = 0; /* Inversion Recovery */ timin = ssi_grad.rfCenterBack + ss_grad.rfCenterFront; timin += 8e-6; // from sp1on/off and after 90 pulse power setting timin += seqtime*(ns-1) + iti_delay; if (ti < timin + 4e-6) // ensure at least a 4us delay abort_message("%s: ti too short, minimum is %.2fms",seqfil,timin*1000); /* Delay after the last IR pulse */ ti_delay = ti - timin; /* force all slices to be acquired back-to-back, with a single TR delay at end */ trtype = 1; } else { iti_delay = ti_delay = 0; } trmin = ns*(seqtime + 4e-6); if (ir[0] == 'y') { trmin += (4e-6 + ssi_grad.rfCenterFront + ti); } if (mintr[0] == 'y'){ tr = trmin; putvalue("tr",tr); } if ((trmin-tr) > 12.5e-9) { abort_message("TR too short. Minimum TR = %.2fms\n",trmin*1000); } tr_delay = (tr - trmin)/ns; /* Set number of segments for profile or full image **********/ nseg = prep_profile(profile[0],nv/etl,&pe_grad,&per_grad); /* Shift DDR for pro *******************************/ roff = -poffset(pro,ro_grad.roamp); /* Calculate total acquisition time */ g_setExpTime(tr*(nt*nseg*getval("arraydim") + ssc) + trimage*getval("arraydim")); /* Return parameters to VnmrJ */ putvalue("rgss",ss_grad.tramp); //90 slice ramp if (ss2_grad.enableButterfly) { //180 slice ramps putvalue("rcrush",ss2_grad.crusher1RampToCrusherDuration); putvalue("rgss2",ss2_grad.crusher1RampToSsDuration); } else { putvalue("rgss2",ss2_grad.tramp); } if (ro_grad.enableButterfly) { putvalue("rgro",ro_grad.crusher1RampToSsDuration); } else { putvalue("rgro",ro_grad.tramp); //RO ramp } putvalue("tror",ror_grad.duration); //ROR duration putvalue("rgror",ror_grad.tramp); //ROR ramp putvalue("gpe",pe_grad.peamp); //PE max amp putvalue("gss",ss_grad.ssamp); putvalue("gro",ro_grad.roamp); /* PULSE SEQUENCE *************************************/ initval(fabs(ssc),vssc); // Compressed steady-state counter assign(one,vacquire); // real-time acquire flag /* Phase cycle: Alternate 180 phase to cancel residual FID */ mod2(ct,vphase180); // 0101 dbl(vphase180,vphase180); // 0202 add(vphase180,one,vphase180); // 1313 Phase difference from 90 add(vphase180,oph,vphase180); obsoffset(resto); delay(4e-6); initval(nseg,vseg); loop(vseg,vseg_ctr); /* TTL scope trigger **********************************/ sp1on(); delay(4e-6); sp1off(); /* Compressed steady-states: 1st array & transient, all arrays if ssc is negative */ if ((ix > 1) && (ssc > 0)) assign(zero,vssc); sub(vseg_ctr,vssc,vseg_ctr); // vpe_ctr counts up from -ssc assign(zero,vssc); ifzero(vseg_ctr); assign(zero,vacquire); // Start acquiring when vseg_ctr reaches zero endif(vseg_ctr); setacqvar(vacquire); // Turn on acquire when vacquire is zero if (ticks) { xgate(ticks); grad_advance(gpropdelay); delay(4e-6); } if(ir[0] == 'y') { /* IR for all slices prior to data acquisition */ obspower(ir_rf.powerCoarse); obspwrf(ir_rf.powerFine); delay(4e-6); msloop(seqcon[1],ns,vms_slices,vms_ctr); obl_shapedgradient(ssi_grad.name,ssi_grad.duration,0,0,ssi_grad.amp,NOWAIT); delay(ssi_grad.rfDelayFront); shapedpulselist(shapelistIR,ssi_grad.rfDuration,oph,rof1,rof2,seqcon[1],vms_ctr); delay(ssi_grad.rfDelayBack); delay(iti_delay); endmsloop(seqcon[1],vms_ctr); delay(ti_delay); } msloop(seqcon[1],ns,vms_slices,vms_ctr); /* Prepulse options ***********************************/ if (sat[0] == 'y') satbands(); if (fsat[0] == 'y') fatsat(); if (mt[0] == 'y') mtc(); /* 90 degree pulse ************************************/ rotate(); obspower(p1_rf.powerCoarse); obspwrf(p1_rf.powerFine); delay(4e-6); obl_shapedgradient(ss_grad.name,ss_grad.duration,0,0,ss_grad.amp,NOWAIT); delay(ss_grad.rfDelayFront); shapedpulselist(shapelist90,ss_grad.rfDuration,oph,rof1,rof2,seqcon[1],vms_ctr); delay(ss_grad.rfDelayBack); /* Read dephase and Slice refocus *********************/ obl_shapedgradient(ssr_grad.name,ssr_grad.duration,ror_grad.amp,0.0,-ssr_grad.amp,WAIT); /* First half-TE delay ********************************/ obspower(p2_rf.powerCoarse); obspwrf(p2_rf.powerFine); delay(te1_delay); peloop(seqcon[2],etl,vetl,vetl_ctr); mult(vseg_ctr,vetl,vpe_ctr); add(vpe_ctr,vetl_ctr,vpe_ctr); getelem(t1,vpe_ctr,vpe_mult); /* 180 degree pulse *******************************/ /* Note, ss2_grad.amp is max gradient for butterfly shape; flat top = _.ssamp */ obl_shapedgradient(ss2_grad.name,ss2_grad.duration,0,0,ss2_grad.amp,NOWAIT); delay(ss2_grad.rfDelayFront); shapedpulselist(shapelist180,ss2_grad.rfDuration,vphase180,rof1,rof2,seqcon[1],vms_ctr); delay(ss2_grad.rfDelayBack); /* Phase-encode gradient ******************************/ pe_shapedgradient(pe_grad.name,pe_grad.duration,0,0,0,-pe_grad.increment,vpe_mult,WAIT); /* Second half-TE period ******************************/ delay(te2_delay); /* Readout gradient ************************************/ obl_shapedgradient(ro_grad.name,ro_grad.duration,ro_grad.amp,0,0,NOWAIT); delay(ro_grad.atDelayFront); /* Acquire data ****************************************/ startacq(alfa); acquire(np,1.0/sw); endacq(); delay(ro_grad.atDelayBack); /* Rewinding phase-encode gradient ********************/ /* Phase encode, refocus, and dephase gradient ******************/ pe_shapedgradient(pe_grad.name,pe_grad.duration,0,0,0,pe_grad.increment,vpe_mult,WAIT); /* Second half-TE delay *******************************/ delay(te3_delay); endpeloop(seqcon[2],vetl_ctr); /* Relaxation delay ***********************************/ if (!trtype) delay(tr_delay); endmsloop(seqcon[1],vms_ctr); if (trtype) delay(ns*tr_delay); endloop(vseg_ctr); /* Inter-image delay **********************************/ sub(ntrt,ct,vtrimage); decr(vtrimage); ifzero(vtrimage); delay(trimage); endif(vtrimage); }
pulsesequence() { /* Internal variable declarations *********************/ double freq90[MAXNSLICE],freq180[MAXNSLICE]; double te_delay1,te_delay2,tr_delay,tau1,tau2,thk2fact,te_delay3=0.0,te_delay4=0.0,navTime=0.0; double crushm0,pem0,gcrushr,gcrushp,gcrushs,pecrush; double refsign=1,crushsign=1,navsign=1; int shape90,shape180,table=0,sepRefocus; char slprofile[MAXSTR]; /* sequence dependent diffusion variables */ double Gro,Gss; // "gdiff" for readout/readout refocus and slice/slice refocus double dgro,dgss; // "delta" for readout/readout refocus and slice/slice refocus double Dgro,Dgss; // "DELTA" for readout/readout refocus and slice/slice refocus double dcrush,dgss2; // "delta" for crusher and gss2 gradients double Dcrush,Dgss2; // "DELTA" for crusher and gss2 gradients int i; /* Real-time variables used in this sequence **********/ int vpe_steps = v1; // Number of PE steps int vpe_ctr = v2; // PE loop counter int vms_slices = v3; // Number of slices int vms_ctr = v4; // Slice loop counter int vpe_offset = v5; // PE/2 for non-table offset int vpe_mult = v6; // PE multiplier, ranges from -PE/2 to PE/2 int vph180 = v7; // Phase of 180 pulse int vph2 = v8; // alternate phase of 180 on odd transients int vssc = v9; // Compressed steady-states int vtrimage = v10; // Counts down from nt, trimage delay when 0 int vacquire = v11; // Argument for setacqvar, to skip steady state acquires int vtrigblock = v12; // Number of slices per trigger block /* Initialize paramaters *****************************/ init_mri(); thk2fact=getval("thk2fact"); pecrush=getval("pecrush"); sepRefocus=getvalnwarn("sepRefocus"); getstrnwarn("slprofile",slprofile); /* Check for external PE table ***********************/ init_tablepar("pelist"); // Initialize pelist parameter if (strcmp(petable,"n") && strcmp(petable,"N") && strcmp(petable,"")) { loadtable(petable); writetabletopar(t1,"pelist"); // Write t1 table to pelist parameter table = 1; } /* RF Power & Bandwidth Calculations ******************/ shape_rf(&p1_rf,"p1",p1pat,p1,flip1,rof1,rof2); shape_rf(&p2_rf,"p2",p2pat,p2,flip2,rof1,rof2); calc_rf(&p1_rf,"tpwr1","tpwr1f"); calc_rf(&p2_rf,"tpwr2","tpwr2f"); /* Initialize gradient structures *********************/ init_slice(&ss_grad,"ss",thk); init_slice(&ss2_grad,"ss2",thk*thk2fact); init_dephase(&crush_grad,"crush"); init_slice_refocus(&ssr_grad,"ssr"); if (FP_LT(tcrushro,alfa)) tcrushro=alfa; init_readout_butterfly(&ro_grad,"ro",lro,np,sw,gcrushro,tcrushro); init_readout_refocus(&ror_grad,"ror"); init_phase(&pe_grad,"pe",lpe,nv); init_generic(&spoil_grad,"spoil",gspoil,tspoil); /* Gradient calculations ******************************/ calc_readout(&ro_grad, WRITE,"gro","sw","at"); ro_grad.m0ref *= grof; calc_readout_refocus(&ror_grad,&ro_grad,NOWRITE,"gror"); calc_phase(&pe_grad,NOWRITE,"gpe","tpe"); calc_slice(&ss_grad,&p1_rf,WRITE,"gss"); calc_slice(&ss2_grad,&p2_rf,WRITE,"gss2"); calc_slice_refocus(&ssr_grad,&ss_grad,WRITE,"gssr"); calc_generic(&spoil_grad,WRITE,"",""); /* Make sure crushing in PE dimension does not refocus signal from 180 */ crushm0=fabs(gcrush*tcrush); pem0=0.0; gcrushp=0.0; if (pecrush) pem0=pe_grad.m0; calc_dephase(&crush_grad,WRITE,crushm0+pem0,"",""); gcrushr = crush_grad.amp*crushm0/crush_grad.m0; if (pecrush) gcrushp = crush_grad.amp; gcrushs = crush_grad.amp*crushm0/crush_grad.m0; /* Allow phase encode and read dephase to be separated from slice refocus */ if (sepRefocus) { /* Equalize read dephase and PE gradient durations */ calc_sim_gradient(&ror_grad,&pe_grad,&null_grad,0,WRITE); crushsign=-1; } else { if (slprofile[0] == 'y') { /* Combined slice refocusing and read dephasing, reverse gradient sign if ror > ssr integral */ refsign = (ss_grad.m0ref > ro_grad.m0ref) ? 1.0 : -1.0; ss_grad.m0ref -= ro_grad.m0ref; calc_slice_refocus(&ssr_grad,&ss_grad,NOWRITE,"gssr"); } /* Equalize both refocus and PE gradient durations */ calc_sim_gradient(&ror_grad,&pe_grad,&ssr_grad,0,WRITE); } /* Create optional prepulse events ********************/ if (fsat[0] == 'y') create_fatsat(); if (sat[0] == 'y') create_satbands(); if (mt[0] == 'y') create_mtc(); if (ir[0] == 'y') create_inversion_recovery(); if (diff[0] == 'y') init_diffusion(&diffusion,&diff_grad,"diff",gdiff,tdelta); sgl_error_check(sglerror); /* Min TE *********************************************/ te = granularity(te,2*GRADIENT_RES); /* tau1, tau2 are the sum of events in each half echo period */ /* tau1, tau2 include a GRADIENT_RES as this is minimum delay time */ tau1 = ss_grad.rfCenterBack + ssr_grad.duration + crush_grad.duration + ss2_grad.rfCenterFront + 2*GRADIENT_RES; tau2 = ss2_grad.rfCenterBack + crush_grad.duration + ro_grad.timeToEcho + GRADIENT_RES; if (sepRefocus) tau2 += ror_grad.duration; temin = 2*MAX(tau1,tau2); /* Diffusion ******************************************/ if (diff[0] == 'y') { /* granulate tDELTA */ tDELTA = granularity(tDELTA,GRADIENT_RES); /* taudiff is the duration of events between diffusion gradients */ taudiff = ss2_grad.duration + 2*crush_grad.duration + GRADIENT_RES; /* set minimum diffusion structure requirements for gradient echo: taudiff, tDELTA, te and minte[0] */ set_diffusion(&diffusion,taudiff,tDELTA,te,minte[0]); /* set additional diffusion structure requirements for spin echo: tau1 and tau2 */ set_diffusion_se(&diffusion,tau1,tau2); /* calculate the diffusion structure delays. address &temin is required in order to update temin accordingly */ calc_diffTime(&diffusion,&temin); } /* TE delays ******************************************/ if (minte[0] == 'y') { te = temin; putvalue("te",te); } if (FP_LT(te,temin)) { abort_message("TE too short, minimum TE = %.3f ms\n",temin*1000); } te_delay1 = te/2 - tau1 + GRADIENT_RES; te_delay2 = te/2 - tau2 + GRADIENT_RES; if (navigator[0] == 'y') { /* tau1, tau2 are the sum of events in each half echo period */ tau1 = ro_grad.timeFromEcho + pe_grad.duration + crush_grad.duration + ss2_grad.rfCenterFront; tau2 = ss2_grad.rfCenterBack + crush_grad.duration + ro_grad.timeToEcho; if (FP_GT(tau1,tau2)) { te_delay3 = GRADIENT_RES; te_delay4 = tau1-tau2+GRADIENT_RES; } else { te_delay3 = tau2-tau1+GRADIENT_RES; te_delay4 = GRADIENT_RES; } navTime = te_delay3 + ss2_grad.duration + 2*crush_grad.duration + ro_grad.duration + te_delay4 + 2*GRADIENT_RES; } /* Check nsblock, the number of slices blocked together (used for triggering and/or inversion recovery) */ check_nsblock(); /* Min TR *********************************************/ trmin = ss_grad.rfCenterFront + te + ro_grad.timeFromEcho + pe_grad.duration + 2*GRADIENT_RES; /* Increase TR if any options are selected ************/ if (spoilflag[0] == 'y') trmin += spoil_grad.duration; if (navigator[0] == 'y') trmin += navTime; if (sat[0] == 'y') trmin += satTime; if (fsat[0] == 'y') trmin += fsatTime; if (mt[0] == 'y') trmin += mtTime; if (ticks > 0) trmin += GRADIENT_RES; /* Adjust for all slices ******************************/ trmin *= ns; /* Inversion recovery *********************************/ if (ir[0] == 'y') { /* tauti is the additional time beyond IR component to be included in ti */ /* satTime, fsatTime and mtTime all included as those modules will be after IR */ tauti = satTime + fsatTime + mtTime + GRADIENT_RES + ss_grad.rfCenterFront; /* calc_irTime checks ti and returns the time of all IR components */ trmin += calc_irTime(tauti,trmin,mintr[0],tr,&trtype); } if (mintr[0] == 'y') { tr = trmin; putvalue("tr",tr); } if (FP_LT(tr,trmin)) { abort_message("TR too short, minimum TR = %.3f ms\n",trmin*1000); } /* TR delay *******************************************/ tr_delay = granularity((tr-trmin)/ns,GRADIENT_RES); /* Calculate B values *********************************/ if (ix == 1) { /* Calculate bvalues according to main diffusion gradients */ calc_bvalues(&diffusion,"dro","dpe","dsl"); /* Add components from additional diffusion encoding imaging gradients peculiar to this sequence */ /* Initialize variables */ dgro = 0.5*(ror_grad.duration+ro_grad.timeToEcho); Gro = ro_grad.m0ref/dgro; Dgro = dgro; if (!sepRefocus) Dgro = te-ss_grad.rfCenterBack-ro_grad.timeToEcho; dgss = 0.5*(ss_grad.rfCenterBack+ssr_grad.duration); Gss = ss_grad.m0ref/dgss; Dgss = dgss; dgss2 = ss2_grad.duration/2; Dgss2 = dgss2; dcrush = crush_grad.duration-crush_grad.tramp; Dcrush = crush_grad.duration+ss2_grad.duration; for (i = 0; i < diffusion.nbval; i++) { /* set droval, dpeval and dslval */ set_dvalues(&diffusion,&droval,&dpeval,&dslval,i); /* Readout */ diffusion.bro[i] += bval(Gro,dgro,Dgro); diffusion.bro[i] += bval(crushsign*gcrushr,dcrush,Dcrush); diffusion.bro[i] += bval_nested(gdiff*droval,tdelta,tDELTA,crushsign*gcrushr,dcrush,Dcrush); if (!sepRefocus) { diffusion.bro[i] += bval_nested(Gro,dgro,Dgro,gdiff*droval,tdelta,tDELTA); diffusion.bro[i] += bval_nested(Gro,dgro,Dgro,crushsign*gcrushr,dcrush,Dcrush); } /* Phase */ if (pecrush) { diffusion.bpe[i] += bval(gcrushp,dcrush,Dcrush); diffusion.bpe[i] += bval_nested(gdiff*dpeval,tdelta,tDELTA,gcrushp,dcrush,Dcrush); } /* Slice */ diffusion.bsl[i] += bval(Gss,dgss,Dgss); diffusion.bsl[i] += bval(gcrushs,dcrush,Dcrush); diffusion.bsl[i] += bval(ss2_grad.ssamp,dgss2,Dgss2); diffusion.bsl[i] += bval_nested(gdiff*dslval,tdelta,tDELTA,gcrushs,dcrush,Dcrush); diffusion.bsl[i] += bval_nested(gdiff*dslval,tdelta,tDELTA,ss2_grad.ssamp,dgss2,Dgss2); diffusion.bsl[i] += bval_nested(gcrushs,dcrush,Dcrush,ss2_grad.ssamp,dgss2,Dgss2); /* Readout/Phase Cross-terms */ diffusion.brp[i] += bval_cross(gdiff*dpeval,tdelta,tDELTA,crushsign*gcrushr,dcrush,Dcrush); diffusion.brp[i] += bval_cross(gdiff*dpeval,tdelta,tDELTA,crushsign*gcrushr,dcrush,Dcrush); if (pecrush) diffusion.brp[i] += bval_cross(gdiff*droval,tdelta,tDELTA,gcrushp,dcrush,Dcrush); if (!sepRefocus) { diffusion.brp[i] += bval_cross(Gro,dgro,Dgro,gdiff*dpeval,tdelta,tDELTA); if (pecrush) diffusion.brp[i] += bval_cross(Gro,dgro,Dgro,gcrushp,dcrush,Dcrush); } /* Readout/Slice Cross-terms */ diffusion.brs[i] += bval2(crushsign*gcrushr,gcrushs,dcrush,Dcrush); diffusion.brs[i] += bval_cross(gdiff*droval,tdelta,tDELTA,gcrushs,dcrush,Dcrush); diffusion.brs[i] += bval_cross(gdiff*dslval,tdelta,tDELTA,crushsign*gcrushr,dcrush,Dcrush); diffusion.brs[i] += bval_cross(gdiff*droval,tdelta,tDELTA,ss2_grad.ssamp,dgss2,Dgss2); if (!sepRefocus) { diffusion.brs[i] += bval_cross(Gro,dgro,Dgro,gdiff*dslval,tdelta,tDELTA); diffusion.brs[i] += bval_cross(Gro,dgro,Dgro,gcrushs,dcrush,Dcrush); diffusion.brs[i] += bval_cross(Gro,dgro,Dgro,ss2_grad.ssamp,dgss2,Dgss2); } /* Slice/Phase Cross-terms */ diffusion.bsp[i] += bval_cross(gdiff*dpeval,tdelta,tDELTA,gcrushs,dcrush,Dcrush); diffusion.bsp[i] += bval_cross(gdiff*dpeval,tdelta,tDELTA,ss2_grad.ssamp,dgss2,Dgss2); if (pecrush) { diffusion.bsp[i] += bval2(gcrushs,gcrushp,dcrush,Dcrush); diffusion.bsp[i] += bval_cross(gdiff*dslval,tdelta,tDELTA,gcrushp,dcrush,Dcrush); diffusion.bsp[i] += bval_cross(gcrushp,dcrush,Dcrush,ss2_grad.ssamp,dgss2,Dgss2); } } /* End for-all-directions */ /* Write the values */ write_bvalues(&diffusion,"bval","bvalue","max_bval"); } /* Generate phase-ramped pulses ***********************/ offsetlist(pss,ss_grad.ssamp,0,freq90,ns,seqcon[1]); offsetlist(pss,ss2_grad.ssamp,0,freq180,ns,seqcon[1]); shape90 = shapelist(p1_rf.pulseName,ss_grad.rfDuration,freq90,ns,ss_grad.rfFraction,seqcon[1]); shape180 = shapelist(p2_rf.pulseName,ss2_grad.rfDuration,freq180,ns,ss2_grad.rfFraction,seqcon[1]); /* Set pe_steps for profile or full image *************/ pe_steps = prep_profile(profile[0],nv,&pe_grad,&null_grad); F_initval(pe_steps/2.0,vpe_offset); /* Shift DDR for pro **********************************/ roff = -poffset(pro,ro_grad.roamp); /* Adjust experiment time for VnmrJ *******************/ if (ssc<0) { if (seqcon[2] == 'c') g_setExpTime(trmean*(ntmean*pe_steps*arraydim - ssc*arraydim)); else g_setExpTime(trmean*(ntmean*pe_steps*arraydim - ssc*pe_steps*arraydim)); } else g_setExpTime(trmean*ntmean*pe_steps*arraydim + tr*ssc); /* Slice profile **************************************/ if (slprofile[0] == 'y' && !sepRefocus) ror_grad.amp = 0; /* Set phase cycle table ******************************/ if (sepRefocus) settable(t2,1,ph180); // Phase encode is just before readout else settable(t2,2,ph180); /* PULSE SEQUENCE *************************************/ status(A); // Set status A rotate(); // Set gradient rotation according to psi, phi and theta triggerSelect(trigger); // Select trigger input 1/2/3 obsoffset(resto); // Set spectrometer frequency delay(GRADIENT_RES); // Delay for frequency setting initval(fabs(ssc),vssc); // Compressed steady-state counter if (seqcon[2]=='s') assign(zero,vssc); // Zero for standard peloop assign(one,vacquire); // real-time acquire flag setacqvar(vacquire); // Turn on acquire when vacquire is zero /* trigger */ if (ticks > 0) F_initval((double)nsblock,vtrigblock); /* Begin phase-encode loop ****************************/ peloop(seqcon[2],pe_steps,vpe_steps,vpe_ctr); if (trtype) delay(ns*tr_delay); // relaxation delay /* Compressed steady-states: 1st array & transient, all arrays if ssc is negative */ if ((ix > 1) && (ssc > 0)) assign(zero,vssc); sub(vpe_ctr,vssc,vpe_ctr); // vpe_ctr counts up from -ssc assign(zero,vssc); if (seqcon[2] == 's') assign(zero,vacquire); // Always acquire for non-compressed loop else { ifzero(vpe_ctr); assign(zero,vacquire); // Start acquiring when vpe_ctr reaches zero endif(vpe_ctr); } /* Read external kspace table if set ******************/ if (table) getelem(t1,vpe_ctr,vpe_mult); else { ifzero(vacquire); sub(vpe_ctr,vpe_offset,vpe_mult); elsenz(vacquire); sub(zero,vpe_offset,vpe_mult); // Hold PE mult at initial value for steady states endif(vacquire); } /* Phase cycle ****************************************/ getelem(t2,vpe_ctr,vph180); // For phase encoding with slice rephase add(oph,vph180,vph180); // 180 deg pulse phase alternates +/- 90 from receiver mod2(ct,vph2); dbl(vph2,vph2); add(vph180,vph2,vph180); // Alternate phase for 180 on odd transients /* Begin multislice loop ******************************/ msloop(seqcon[1],ns,vms_slices,vms_ctr); if (!trtype) delay(tr_delay); // Relaxation delay if (ticks > 0) { modn(vms_ctr,vtrigblock,vtest); ifzero(vtest); // if the beginning of an trigger block xgate(ticks); grad_advance(gpropdelay); delay(GRADIENT_RES); elsenz(vtest); delay(GRADIENT_RES); endif(vtest); } sp1on(); delay(GRADIENT_RES); sp1off(); // Scope trigger /* Prepulse options ***********************************/ if (ir[0] == 'y') inversion_recovery(); if (sat[0] == 'y') satbands(); if (fsat[0] == 'y') fatsat(); if (mt[0] == 'y') mtc(); /* Slice select RF pulse ******************************/ obspower(p1_rf.powerCoarse); obspwrf(p1_rf.powerFine); delay(GRADIENT_RES); obl_shapedgradient(ss_grad.name,ss_grad.duration,0,0,ss_grad.amp,NOWAIT); delay(ss_grad.rfDelayFront); shapedpulselist(shape90,ss_grad.rfDuration,oph,rof1,rof2,seqcon[1],vms_ctr); delay(ss_grad.rfDelayBack); /* Slice refocus gradient *****************************/ if (sepRefocus) obl_shapedgradient(ssr_grad.name,ssr_grad.duration,0,0,-ssr_grad.amp,WAIT); else /* Include phase encode and readout dephase gradient if refocus gradients not separated */ pe_shapedgradient(pe_grad.name,pe_grad.duration,ror_grad.amp,0,-ssr_grad.amp*refsign,pe_grad.increment,vpe_mult,WAIT); if (diff[0] == 'y') { delay(diffusion.d1); diffusion_dephase(&diffusion,dro,dpe,dsl); delay(diffusion.d2); } else delay(te_delay1); /* Refocusing RF pulse ********************************/ obspower(p2_rf.powerCoarse); obspwrf(p2_rf.powerFine); delay(GRADIENT_RES); obl_shapedgradient(crush_grad.name,crush_grad.duration,crushsign*gcrushr,gcrushp,gcrushs,WAIT); obl_shapedgradient(ss2_grad.name,ss2_grad.duration,0,0,ss2_grad.amp,NOWAIT); delay(ss2_grad.rfDelayFront); shapedpulselist(shape180,ss2_grad.rfDuration,vph180,rof2,rof2,seqcon[1],vms_ctr); delay(ss2_grad.rfDelayBack); obl_shapedgradient(crush_grad.name,crush_grad.duration,crushsign*gcrushr,gcrushp,gcrushs,WAIT); if (diff[0] == 'y') { delay(diffusion.d3); diffusion_rephase(&diffusion,dro,dpe,dsl); delay(diffusion.d4); } else delay(te_delay2); /* Readout dephase, phase encode & readout gradients **/ roff = -poffset(pro,ro_grad.roamp); // incase inverted navigator is acquired if (slprofile[0] == 'y') { /* Readout gradient only if refocus gradients not separated */ if (sepRefocus) obl_shapedgradient(ror_grad.name,ror_grad.duration,0,0,-ror_grad.amp,WAIT); obl_shapedgradient(ro_grad.name,ro_grad.duration,0,0,ro_grad.amp,NOWAIT); } else { /* Readout gradient only if refocus gradients not separated */ if (sepRefocus) pe_shapedgradient(pe_grad.name,pe_grad.duration,-ror_grad.amp,0,0,-pe_grad.increment,vpe_mult,WAIT); obl_shapedgradient(ro_grad.name,ro_grad.duration,ro_grad.amp,0,0,NOWAIT); } /* Acquisition ****************************************/ delay(ro_grad.atDelayFront-alfa); startacq(alfa); acquire(np,1.0/sw); delay(ro_grad.atDelayBack); endacq(); /* Rewind Phase encoding ******************************/ pe_shapedgradient(pe_grad.name,pe_grad.duration,0,0,0,pe_grad.increment,vpe_mult,WAIT); /* Navigator acquisition ******************************/ if (navigator[0] == 'y') { delay(te_delay3); obl_shapedgradient(crush_grad.name,crush_grad.duration,-crushsign*gcrushr,0,-gcrushs,WAIT); obl_shapedgradient(ss2_grad.name,ss2_grad.duration,0,0,ss2_grad.amp,NOWAIT); delay(ss2_grad.rfDelayFront); shapedpulselist(shape180,ss2_grad.rfDuration,vph180,rof2,rof2,seqcon[1],vms_ctr); delay(ss2_grad.rfDelayBack); obl_shapedgradient(crush_grad.name,crush_grad.duration,-crushsign*gcrushr,0,-gcrushs,WAIT); delay(te_delay4); obl_shapedgradient(ro_grad.name,ro_grad.duration,navsign*ro_grad.amp,0,0,NOWAIT); delay(ro_grad.atDelayFront-alfa); startacq(alfa); acquire(np,1.0/sw); delay(ro_grad.atDelayBack); endacq(); } if (spoilflag[0] == 'y') { obl_shapedgradient(spoil_grad.name,spoil_grad.duration,navsign*spoil_grad.amp,0,spoil_grad.amp,WAIT); } endmsloop(seqcon[1],vms_ctr); endpeloop(seqcon[2],vpe_ctr); /* Inter-image delay **********************************/ sub(ntrt,ct,vtrimage); decr(vtrimage); ifzero(vtrimage); delay(trimage); endif(vtrimage); /* Duty cycle *****************************************/ calc_grad_duty(tr); }
pulsesequence() { /* Internal variable declarations *************************/ double freqEx[MAXNSLICE]; double maxgradtime,spoilMoment,perTime,tau1,te_delay,tr_delay; double te2=0.0,te3=0.0,te2min,te3min,tau2,tau3,te2_delay,te3_delay=0; char minte2[MAXSTR],minte3[MAXSTR],spoilflag[MAXSTR]; int sepSliceRephase,sepReadRephase=0,readrev,table,shapeEx; int i; /* Real-time variables used in this sequence **************/ int vpe_steps = v1; // Number of PE steps int vpe_ctr = v2; // PE loop counter int vms_slices = v3; // Number of slices int vms_ctr = v4; // Slice loop counter int vpe_offset = v5; // PE/2 for non-table offset int vpe_mult = v6; // PE multiplier, ranges from -PE/2 to PE/2 int vper_mult = v7; // PE rewinder multiplier; turn off rewinder when 0 int vssc = v8; // Compressed steady-states int vacquire = v9; // Argument for setacqvar, to skip steady state acquires int vrfspoil_ctr = v10; // RF spoil counter int vrfspoil = v11; // RF spoil multiplier int vtrimage = v12; // Counts down from nt, trimage delay when 0 int vne = v13; // Number of echoes int vne_ctr = v14; // Echo loop counter int vneindex = v15; // Echo index, odd or even int vnelast = v16; // Check for last echo int vtrigblock = v17; // Number of slices per trigger block /* Initialize paramaters **********************************/ init_mri(); getstr("spoilflag",spoilflag); te2=getval("te2"); te3=getval("te3"); getstr("minte2",minte2); getstr("minte3",minte3); readrev=(int)getval("readrev"); /* Check for external PE table ***************************/ table = 0; if (strcmp(petable,"n") && strcmp(petable,"N") && strcmp(petable,"")) { loadtable(petable); table = 1; } /* Set Rcvr/Xmtr phase increments for RF Spoiling ********/ /* Ref: Zur, Y., Magn. Res. Med., 21, 251, (1991) *******/ if (rfspoil[0] == 'y') { rcvrstepsize(rfphase); obsstepsize(rfphase); } /* Initialize gradient structures *************************/ shape_rf(&p1_rf,"p1",p1pat,p1,flip1,rof1,rof2 ); // excitation pulse init_slice(&ss_grad,"ss",thk); // slice select gradient init_slice_refocus(&ssr_grad,"ssr"); // slice refocus gradient init_readout(&ro_grad,"ro",lro,np,sw); // readout gradient ro_grad.pad1=alfa; ro_grad.pad2=alfa; init_readout_refocus(&ror_grad,"ror"); // dephase gradient init_phase(&pe_grad,"pe",lpe,nv); // phase encode gradient init_dephase(&spoil_grad,"spoil"); // optimized spoiler init_dephase(&ref_grad,"ref"); // readout rephase /* RF Calculations ****************************************/ calc_rf(&p1_rf,"tpwr1","tpwr1f"); /* Gradient calculations **********************************/ calc_slice(&ss_grad,&p1_rf,WRITE,"gss"); calc_slice_refocus(&ssr_grad, &ss_grad,WRITE,"gssr"); calc_readout(&ro_grad, WRITE,"gro","sw","at"); calc_readout_refocus(&ror_grad,&ro_grad,NOWRITE,"gror"); calc_phase(&pe_grad, NOWRITE,"gpe","tpe"); calc_dephase(&ref_grad,WRITE,ro_grad.m0,"",""); spoilMoment = ro_grad.acqTime*ro_grad.roamp; // Optimal spoiling is at*gro for 2pi per pixel spoilMoment -= ro_grad.m0def; // Subtract partial spoiling from back half of readout calc_dephase(&spoil_grad,WRITE,spoilMoment,"gspoil","tspoil"); /* Is TE long enough for separate slice refocus? ******/ maxgradtime = MAX(ror_grad.duration,pe_grad.duration); if (spoilflag[0] == 'y') maxgradtime = MAX(maxgradtime,spoil_grad.duration); tau1 = ss_grad.rfCenterBack + ssr_grad.duration + maxgradtime + ro_grad.timeToEcho + GRADIENT_RES; /* Equalize refocus and PE gradient durations *********/ if ((te >= tau1) && (minte[0] != 'y')) { sepSliceRephase = 1; // Set flag for separate slice rephase calc_sim_gradient(&ror_grad,&pe_grad,&spoil_grad,tpemin,WRITE); } else { sepSliceRephase = 0; calc_sim_gradient(&ror_grad,&pe_grad,&ssr_grad,tpemin,WRITE); calc_sim_gradient(&ror_grad,&spoil_grad,&null_grad,tpemin,NOWRITE); } perTime = 0.0; if ((perewind[0] == 'y') || (spoilflag[0] == 'y')) perTime = spoil_grad.duration; if (spoilflag[0] == 'n') spoil_grad.amp = 0.0; /* Create optional prepulse events ************************/ if (sat[0] == 'y') create_satbands(); if (fsat[0] == 'y') create_fatsat(); if (mt[0] == 'y') create_mtc(); if (ir[0] == 'y') create_inversion_recovery(); /* Set up frequency offset pulse shape list ********/ offsetlist(pss,ss_grad.ssamp,0,freqEx,ns,seqcon[1]); shapeEx = shapelist(p1_rf.pulseName,ss_grad.rfDuration,freqEx,ns,ss_grad.rfFraction,seqcon[1]); /* Check that all Gradient calculations are ok ************/ sgl_error_check(sglerror); /* Min TE ******************************************/ tau1 = ss_grad.rfCenterBack + pe_grad.duration + ro_grad.timeToEcho; tau1 += (sepSliceRephase) ? ssr_grad.duration : 0.0; // Add slice refocusing if separate event temin = tau1 + GRADIENT_RES; /* ensure that te_delay is at least GRADIENT_RES */ te = granularity(te,GRADIENT_RES); if (minte[0] == 'y') { te = temin; putvalue("te",te); } if (FP_LT(te,temin)) { abort_message("TE too short. Minimum TE= %.3fms\n",temin*1000); } te_delay = te - tau1; /* Min TE2 *****************************************/ tau2 = (readrev) ? 2*ro_grad.timeFromEcho : ro_grad.duration+ref_grad.duration; te2min = tau2 + GRADIENT_RES; te2 = granularity(te2,GRADIENT_RES); if (minte2[0] == 'y') { te2 = te2min; putvalue("te2",te2); } if (FP_LT(te2,te2min)) { abort_message("TE2 too short. Minimum TE2= %.3fms\n",te2min*1000); } if (readrev) te2_delay = te2 - tau2; else { tau2 = ro_grad.duration + 3*ror_grad.duration; if (te2 >= tau2) { sepReadRephase = 1; // Set flag for separate read rephase te2_delay = te2 - ro_grad.duration - 2*ror_grad.duration; } else { sepReadRephase = 0; if (te2 > te2min+GRADIENT_RES) { ref_grad.duration = granularity(te2-ro_grad.duration-2*GRADIENT_RES,GRADIENT_RES); ref_grad.calcFlag = AMPLITUDE_FROM_MOMENT_DURATION; calc_dephase(&ref_grad,WRITE,ro_grad.m0,"",""); } te2_delay = te2 - ro_grad.duration - ref_grad.duration; } } /* Min TE3 *****************************************/ if (readrev) { tau3 = 2*ro_grad.timeToEcho; te3min = tau3 + GRADIENT_RES; te3 = granularity(te3,GRADIENT_RES); if (minte3[0] == 'y') { te3 = te3min; putvalue("te3",te3); } if (FP_LT(te3,te3min)) { abort_message("TE3 too short. Minimum TE3= %.3fms\n",te3min*1000); } te3_delay = te3 - tau3; } /* Now set the TE array accordingly */ putCmd("TE = 0"); /* Re-initialize TE */ putCmd("TE[1] = %f",te*1000); if (readrev) { for (i=1;i<ne;i++) { if (i%2 == 0) putCmd("TE[%d] = TE[%d]+%f",i+1,i,te3*1000); else putCmd("TE[%d] = TE[%d]+%f",i+1,i,te2*1000); } } else { for (i=1;i<ne;i++) putCmd("TE[%d] = TE[%d]+%f",i+1,i,te2*1000); } /* Check nsblock, the number of slices blocked together (used for triggering and/or inversion recovery) */ check_nsblock(); /* Min TR ******************************************/ trmin = ss_grad.duration + te_delay + pe_grad.duration + ne*ro_grad.duration + perTime + 2*GRADIENT_RES; trmin += (sepSliceRephase) ? ssr_grad.duration : 0.0; // Add slice refocusing if separate event if (readrev) trmin += (ne/2)*te2_delay + ((ne-1)/2)*te3_delay; else trmin += (sepReadRephase) ? (ne-1)*(te2_delay+2*ror_grad.duration) : (ne-1)*(te2_delay+ref_grad.duration); /* Increase TR if any options are selected *********/ if (sat[0] == 'y') trmin += satTime; if (fsat[0] == 'y') trmin += fsatTime; if (mt[0] == 'y') trmin += mtTime; if (ticks > 0) trmin += GRADIENT_RES; /* Adjust for all slices ***************************/ trmin *= ns; /* Inversion recovery *********************************/ if (ir[0] == 'y') { /* tauti is the additional time beyond IR component to be included in ti */ /* satTime, fsatTime and mtTime all included as those modules will be after IR */ tauti = satTime + fsatTime + mtTime + GRADIENT_RES + ss_grad.rfCenterFront; /* calc_irTime checks ti and returns the time of all IR components */ trmin += calc_irTime(tauti,trmin,mintr[0],tr,&trtype); } if (mintr[0] == 'y') { tr = trmin; putvalue("tr",tr); } if (FP_LT(tr,trmin)) { abort_message("TR too short. Minimum TR = %.3fms\n",trmin*1000); } /* Calculate tr delay */ tr_delay = granularity((tr-trmin)/ns,GRADIENT_RES); /* Set pe_steps for profile or full image **********/ pe_steps = prep_profile(profile[0],nv,&pe_grad,&per_grad); F_initval(pe_steps/2.0,vpe_offset); /* Shift DDR for pro *******************************/ roff = -poffset(pro,ro_grad.roamp); /* Adjust experiment time for VnmrJ *********************/ if (ssc<0) { if (seqcon[2] == 'c') g_setExpTime(trmean*(ntmean*pe_steps*arraydim - ssc*arraydim)); else g_setExpTime(trmean*(ntmean*pe_steps*arraydim - ssc*pe_steps*arraydim)); } else g_setExpTime(trmean*ntmean*pe_steps*arraydim + tr*ssc); /* PULSE SEQUENCE ***************************************/ status(A); rotate(); triggerSelect(trigger); // Select trigger input 1/2/3 obsoffset(resto); delay(GRADIENT_RES); initval(fabs(ssc),vssc); // Compressed steady-state counter if (seqcon[2]=='s') assign(zero,vssc); // Zero for standard peloop assign(zero,vrfspoil_ctr); // RF spoil phase counter assign(zero,vrfspoil); // RF spoil multiplier assign(one,vacquire); // real-time acquire flag setacqvar(vacquire); // Turn on acquire when vacquire is zero /* trigger */ if (ticks > 0) F_initval((double)nsblock,vtrigblock); /* Begin phase-encode loop ****************************/ peloop(seqcon[2],pe_steps,vpe_steps,vpe_ctr); if (trtype) delay(ns*tr_delay); // relaxation delay /* Compressed steady-states: 1st array & transient, all arrays if ssc is negative */ if ((ix > 1) && (ssc > 0)) assign(zero,vssc); sub(vpe_ctr,vssc,vpe_ctr); // vpe_ctr counts up from -ssc assign(zero,vssc); if (seqcon[2] == 's') assign(zero,vacquire); // Always acquire for non-compressed loop else { ifzero(vpe_ctr); assign(zero,vacquire); // Start acquiring when vpe_ctr reaches zero endif(vpe_ctr); } /* Set rcvr/xmtr phase for RF spoiling *******************/ if (rfspoil[0] == 'y') { incr(vrfspoil_ctr); // vrfspoil_ctr = 1 2 3 4 5 6 add(vrfspoil,vrfspoil_ctr,vrfspoil); // vrfspoil = 1 3 6 10 15 21 xmtrphase(vrfspoil); rcvrphase(vrfspoil); } /* Read external kspace table if set ******************/ if (table) getelem(t1,vpe_ctr,vpe_mult); else { ifzero(vacquire); sub(vpe_ctr,vpe_offset,vpe_mult); elsenz(vacquire); sub(zero,vpe_offset,vpe_mult); // Hold PE mult at initial value for steady states endif(vacquire); } /* PE rewinder follows PE table; zero if turned off ***/ if (perewind[0] == 'y') assign(vpe_mult,vper_mult); else assign(zero,vper_mult); /* Begin multislice loop ******************************/ msloop(seqcon[1],ns,vms_slices,vms_ctr); if (!trtype) delay(tr_delay); // Relaxation delay if (ticks > 0) { modn(vms_ctr,vtrigblock,vtest); ifzero(vtest); // if the beginning of an trigger block xgate(ticks); grad_advance(gpropdelay); delay(GRADIENT_RES); elsenz(vtest); delay(GRADIENT_RES); endif(vtest); } /* TTL scope trigger **********************************/ sp1on(); delay(GRADIENT_RES); sp1off(); /* Prepulse options ***********************************/ if (ir[0] == 'y') inversion_recovery(); if (sat[0] == 'y') satbands(); if (fsat[0] == 'y') fatsat(); if (mt[0] == 'y') mtc(); /* Slice select RF pulse ******************************/ obspower(p1_rf.powerCoarse); obspwrf(p1_rf.powerFine); delay(GRADIENT_RES); obl_shapedgradient(ss_grad.name,ss_grad.duration,0,0,ss_grad.amp,NOWAIT); delay(ss_grad.rfDelayFront); shapedpulselist(shapeEx,ss_grad.rfDuration,oph,rof1,rof2,seqcon[1],vms_ctr); delay(ss_grad.rfDelayBack); /* Phase encode, refocus, and dephase gradient ********/ if (sepSliceRephase) { // separate slice refocus gradient obl_shapedgradient(ssr_grad.name,ssr_grad.duration,0,0,-ssr_grad.amp,WAIT); delay(te_delay); // delay between slab refocus and pe pe_shapedgradient(pe_grad.name,pe_grad.duration,-ror_grad.amp,0,0, -pe_grad.increment,vpe_mult,WAIT); } else { pe_shapedgradient(pe_grad.name,pe_grad.duration,-ror_grad.amp,0,-ssr_grad.amp, -pe_grad.increment,vpe_mult,WAIT); delay(te_delay); // delay after refocus/pe } F_initval(ne,vne); loop(vne,vne_ctr); if (readrev) { mod2(vne_ctr,vneindex); ifzero(vneindex); /* Shift DDR for pro *******************************/ roff = -poffset(pro,ro_grad.roamp); /* Readout gradient ********************************/ obl_shapedgradient(ro_grad.name,ro_grad.duration,ro_grad.amp,0,0,NOWAIT); delay(ro_grad.atDelayFront-alfa); /* Acquisition ***************************************/ startacq(alfa); acquire(np,1.0/sw); delay(ro_grad.atDelayBack); endacq(); sub(vne,vne_ctr,vnelast); sub(vnelast,one,vnelast); ifzero(vnelast); elsenz(vnelast); delay(te2_delay); endif(vnelast); elsenz(vneindex); /* Shift DDR for pro *******************************/ roff = -poffset(pro,-ro_grad.roamp); /* Readout gradient ********************************/ obl_shapedgradient(ro_grad.name,ro_grad.duration,-ro_grad.amp,0,0,NOWAIT); delay(ro_grad.atDelayFront-alfa); /* Acquisition ***************************************/ startacq(alfa); acquire(np,1.0/sw); delay(ro_grad.atDelayBack); endacq(); sub(vne,vne_ctr,vnelast); sub(vnelast,one,vnelast); ifzero(vnelast); elsenz(vnelast); delay(te3_delay); endif(vnelast); endif(vneindex); } else { /* Shift DDR for pro *******************************/ roff = -poffset(pro,ro_grad.roamp); /* Readout gradient ********************************/ obl_shapedgradient(ro_grad.name,ro_grad.duration,ro_grad.amp,0,0,NOWAIT); delay(ro_grad.atDelayFront-alfa); /* Acquisition ***************************************/ startacq(alfa); acquire(np,1.0/sw); delay(ro_grad.atDelayBack); endacq(); sub(vne,vne_ctr,vnelast); sub(vnelast,one,vnelast); ifzero(vnelast); elsenz(vnelast); if (sepReadRephase) { obl_shapedgradient(ror_grad.name,ror_grad.duration,-ror_grad.amp,0,0,WAIT); delay(te2_delay); obl_shapedgradient(ror_grad.name,ror_grad.duration,-ror_grad.amp,0,0,WAIT); } else { obl_shapedgradient(ref_grad.name,ref_grad.duration,-ref_grad.amp,0,0,WAIT); delay(te2_delay); } endif(vnelast); } endloop(vne_ctr); /* Rewind / spoiler gradient **************************/ if ((perewind[0] == 'y') || (spoilflag[0] == 'y')) { pe_shapedgradient(pe_grad.name,pe_grad.duration,spoil_grad.amp,0,0,pe_grad.increment,vper_mult,WAIT); } endmsloop(seqcon[1],vms_ctr); endpeloop(seqcon[2],vpe_ctr); /* Inter-image delay **********************************/ sub(ntrt,ct,vtrimage); decr(vtrimage); ifzero(vtrimage); delay(trimage); endif(vtrimage); }
pulsesequence() { /* Internal variable declarations *************************/ double freqEx[MAXNSLICE], freqIR[MAXNSLICE]; double pe_steps,pespoil_amp; double perTime, seqtime, tau1, tauIR=0, te_delay, tr_delay, ti_delay=0; int table, shapeEx, shapeIR=0; char spoilflag[MAXSTR],per_name[MAXSTR]; /* Real-time variables used in this sequence **************/ int vpe_steps = v1; // Number of PE steps int vpe_ctr = v2; // PE loop counter int vms_slices = v3; // Number of slices int vms_ctr = v4; // Slice loop counter int vpe_offset = v5; // PE/2 for non-table offset int vpe_mult = v6; // PE multiplier, ranges from -PE/2 to PE/2 int vper_mult = v7; // PE rewinder multiplier; turn off rewinder when 0 int vssc = v8; // Compressed steady-states int vacquire = v9; // Argument for setacqvar, to skip steady state acquires int vrfspoil_ctr = v10; // RF spoil counter int vrfspoil = v11; // RF spoil multiplier int vtrimage = v12; // Counts down from nt, trimage delay when 0 /* Initialize paramaters **********************************/ get_parameters(); get_ovsparameters(); getstr("spoilflag",spoilflag); /* Check for external PE table ***************************/ table = 0; if (strcmp(petable,"n") && strcmp(petable,"N") && strcmp(petable,"")) { loadtable(petable); table = 1; } /* Set Rcvr/Xmtr phase increments for RF Spoiling ********/ /* Ref: Zur, Y., Magn. Res. Med., 21, 251, (1991) *******/ if (rfspoil[0] == 'y') { rcvrstepsize(rfphase); obsstepsize(rfphase); } /* Initialize gradient structures *************************/ init_rf(&p1_rf,p1pat,p1,flip1,rof1,rof2 ); // excitation pulse init_slice(&ss_grad,"ss",thk); // slice select gradient init_slice_refocus(&ssr_grad,"ssr"); // slice refocus gradient init_readout(&ro_grad,"ro",lro,np,sw); // readout gradient init_readout_refocus(&ror_grad,"ror"); // dephase gradient init_phase(&pe_grad,"pe",lpe,nv); // phase encode gradient init_phase(&per_grad,"per",lpe,nv); // phase encode gradient init_generic(&spoil_grad,"spoil",gspoil,tspoil); // spoiler gradient /* RF Calculations ****************************************/ calc_rf(&p1_rf,"tpwr1","tpwr1f"); /* Gradient calculations **********************************/ calc_slice(&ss_grad,&p1_rf,WRITE,"gss"); calc_slice_refocus(&ssr_grad, &ss_grad, NOWRITE,"gssr"); calc_readout(&ro_grad, WRITE, "gro","sw","at"); calc_readout_refocus(&ror_grad, &ro_grad, NOWRITE, "gror"); calc_phase(&pe_grad, NOWRITE, "gpe","tpe"); /* Equalize refocus and PE gradient durations *************/ calc_sim_gradient(&ror_grad, &pe_grad, &ssr_grad,tpemin, WRITE); /* Calculate phase-rewind & spoiler gradients *************/ pespoil_amp = 0.0; perTime = 0.0; if ((perewind[0] == 'y') && (spoilflag[0] == 'n')) { // Rewinder, no spoiler calc_phase(&per_grad,WRITE,"",""); strcpy(per_name,per_grad.name); perTime = per_grad.duration; spoil_grad.amp = 0.0; } else if ((perewind[0] == 'n') && (spoilflag[0] == 'y')) { // Spoiler, no rewinder calc_generic(&spoil_grad,WRITE,"",""); strcpy(per_name,spoil_grad.name); perTime = spoil_grad.duration; pespoil_amp = spoil_grad.amp; // Apply spoiler on PE axis if no rewinder } else if ((perewind[0] == 'y') && (spoilflag[0] == 'y')) { // Rewinder and spoiler calc_phase(&per_grad,NOWRITE,"",""); calc_generic(&spoil_grad,NOWRITE,"",""); calc_sim_gradient(&per_grad,&spoil_grad,&null_grad,0.0,WRITE); strcpy(per_name,per_grad.name); perTime = per_grad.duration; } /* Create optional prepulse events ************************/ if (sat[0] == 'y') create_satbands(); if (fsat[0] == 'y') create_fatsat(); if (mt[0] == 'y') create_mtc(); if (ovs[0] == 'y') { /* Must set up a few voxel specific parameters for create_ovsbands() to function */ vox1_grad.thickness = vox1; vox2_grad.thickness = vox2; vox3_grad.thickness = vox3; vox1_grad.rfBandwidth = vox2_grad.rfBandwidth = vox3_grad.rfBandwidth = p1_rf.bandwidth; create_ovsbands(); } if (ir[0] == 'y') { init_rf(&ir_rf,pipat,pi,flipir,rof2,rof2); calc_rf(&ir_rf,"tpwri","tpwrif"); init_slice_butterfly(&ssi_grad,"ssi",thk,gcrush,tcrush); calc_slice(&ssi_grad,&ir_rf,WRITE,"gssi"); tauIR = ss_grad.duration - ss_grad.rfCenterBack; // Duration of ss_grad before RF center ti_delay = ti - (ssi_grad.rfCenterFront + tauIR); if (ti_delay < 0) { abort_message("TI too short, Minimum TI = %.2fms\n",(ti-ti_delay)*1000); } irTime = 4e-6 + ti + ssi_grad.duration - ssi_grad.rfCenterBack; // Time to add to TR } /* Check that all Gradient calculations are ok ************/ sgl_error_check(sglerror); /* Min TE ******************************************/ tau1 = ss_grad.rfCenterBack + pe_grad.duration + alfa + ro_grad.timeToEcho; temin = tau1 + 4e-6; /* ensure that te_delay is at least 4us */ if (minte[0] == 'y') { te = temin; putvalue("te",te); } if (te < temin) { abort_message("TE too short. Minimum TE= %.2fms\n",temin*1000+0.005); } te_delay = te - tau1; /* Min TR ******************************************/ seqtime = ss_grad.duration + te_delay + pe_grad.duration + ro_grad.duration + perTime + tep + alfa; /* Increase TR if any options are selected ****************/ if (sat[0] == 'y') seqtime += satTime; if (fsat[0] == 'y') seqtime += fsatTime; if (mt[0] == 'y') seqtime += mtTime; if (ovs[0] == 'y') seqtime += ovsTime; if (ir[0] == 'y') { seqtime += irTime; seqtime -= tauIR; /* subtract out ss_grad which was already included in TR */ } trmin = seqtime + 4e-6; /* ensure that tr_delay is at least 4us */ trmin *= ns; if (mintr[0] == 'y') { tr = trmin; putvalue("tr",tr); } if (tr < trmin) { abort_message("TR too short. Minimum TR= %.2fms\n",trmin*1000+0.005); } tr_delay = (tr - seqtime*ns)/ns; /* Set up frequency offset pulse shape list ********/ offsetlist(pss,ss_grad.ssamp,0,freqEx,ns,seqcon[1]); shapeEx = shapelist(p1pat,ss_grad.rfDuration,freqEx,ns,0,seqcon[1]); if (ir[0] == 'y') { offsetlist(pss,ssi_grad.ssamp,0,freqIR,ns,seqcon[1]); shapeIR = shapelist(pipat,ssi_grad.rfDuration,freqIR,ns,0,seqcon[1]); } /* Set pe_steps for profile or full image **********/ pe_steps = prep_profile(profile[0],nv,&pe_grad,&per_grad); initval(pe_steps/2.0,vpe_offset); /* Shift DDR for pro *******************************/ roff = -poffset(pro,ro_grad.roamp); g_setExpTime(tr*(nt*pe_steps*arraydim + ssc)); /* PULSE SEQUENCE *************************************/ status(A); rotate(); obsoffset(resto); delay(4e-6); initval(fabs(ssc),vssc); // Compressed steady-state counter assign(zero,vrfspoil_ctr); // RF spoil phase counter assign(zero,vrfspoil); // RF spoil multiplier assign(one,vacquire); // real-time acquire flag setacqvar(vacquire); // Turn on acquire when vacquire is zero /* Delay all channels except gradient *****************/ sub(ssval,ssctr,v30); add(v30,ct,v30); if (ix == 1) { ifzero(v30); grad_advance(tep); endif(v30); } /* Begin phase-encode loop ****************************/ peloop(seqcon[2],pe_steps,vpe_steps,vpe_ctr); /* Compressed steady-states: 1st array & transient, all arrays if ssc is negative */ if ((ix > 1) && (ssc > 0)) assign(zero,vssc); sub(vpe_ctr,vssc,vpe_ctr); // vpe_ctr counts up from -ssc assign(zero,vssc); if (seqcon[2] == 's') assign(zero,vacquire); // Always acquire for non-compressed loop else { ifzero(vpe_ctr); assign(zero,vacquire); // Start acquiring when vpe_ctr reaches zero endif(vpe_ctr); } /* Set rcvr/xmtr phase for RF spoiling *******************/ if (rfspoil[0] == 'y') { incr(vrfspoil_ctr); // vrfspoil_ctr = 1 2 3 4 5 6 add(vrfspoil,vrfspoil_ctr,vrfspoil); // vrfspoil = 1 3 6 10 15 21 xmtrphase(vrfspoil); rcvrphase(vrfspoil); } /* Read external kspace table if set ******************/ if (table) getelem(t1,vpe_ctr,vpe_mult); else { ifzero(vacquire); sub(vpe_ctr,vpe_offset,vpe_mult); elsenz(vacquire); sub(zero,vpe_offset,vpe_mult); // Hold PE mult at initial value for steady states endif(vacquire); } /* PE rewinder follows PE table; zero if turned off ***/ if (perewind[0] == 'y') assign(vpe_mult,vper_mult); else assign(zero,vper_mult); /* Begin multislice loop ******************************/ msloop(seqcon[1],ns,vms_slices,vms_ctr); triggerSelect(trigger); // Selectable trigger input delay(4e-6); if (ticks) { xgate(ticks); grad_advance(tep); // Gradient propagation delay } /* TTL scope trigger **********************************/ sp1on(); delay(4e-6); sp1off(); /* Prepulse options ***********************************/ if (sat[0] == 'y') satbands(); if (fsat[0] == 'y') fatsat(); if (mt[0] == 'y') mtc(); if (ovs[0] == 'y') {ovsbands(); rotate();} /* Optional IR pulse **********************************/ if (ir[0] == 'y') { obspower(ir_rf.powerCoarse); obspwrf(ir_rf.powerFine); delay(4e-6); obl_shapedgradient(ssi_grad.name,ssi_grad.duration,0,0,ssi_grad.amp,NOWAIT); delay(ssi_grad.rfDelayFront); shapedpulselist(shapeIR,ssi_grad.rfDuration,oph,rof2,rof2,seqcon[1],vms_ctr); delay(ssi_grad.rfDelayBack); delay(ti_delay); } /* Slice select RF pulse ******************************/ obspower(p1_rf.powerCoarse); obspwrf(p1_rf.powerFine); delay(4e-6); obl_shapedgradient(ss_grad.name,ss_grad.duration,0,0,ss_grad.amp,NOWAIT); delay(ss_grad.rfDelayFront); shapedpulselist(shapeEx,ss_grad.rfDuration,oph,rof1,rof2,seqcon[1],vms_ctr); delay(ss_grad.rfDelayBack); /* Phase encode, refocus, and dephase gradient ********/ pe_shapedgradient(pe_grad.name,pe_grad.duration,-ror_grad.amp,0,-ssr_grad.amp, -pe_grad.increment,vpe_mult,WAIT); /* TE delay *******************************************/ delay(te_delay); /* Readout gradient and acquisition ********************/ obl_shapedgradient(ro_grad.name,ro_grad.duration,ro_grad.amp,0,0,NOWAIT); delay(ro_grad.atDelayFront); startacq(alfa); acquire(np,1.0/sw); delay(ro_grad.atDelayBack); endacq(); /* Rewind / spoiler gradient *********************************/ if ((perewind[0] == 'y') || (spoilflag[0] == 'y')) { pe_shapedgradient(per_name,perTime,spoil_grad.amp,pespoil_amp,spoil_grad.amp, per_grad.increment,vper_mult,WAIT); } /* Relaxation delay ***********************************/ if (!trtype) delay(tr_delay); endmsloop(seqcon[1],vms_ctr); if (trtype) delay(ns*tr_delay); endpeloop(seqcon[2],vpe_ctr); /* Inter-image delay **********************************/ sub(ntrt,ct,vtrimage); decr(vtrimage); ifzero(vtrimage); delay(trimage); endif(vtrimage); }
pulsesequence() { /* Internal variable declarations *************************/ double freq90[MAXNSLICE],freq180[MAXNSLICE],freqIR[MAXNSLICE]; int shape90=0, shape180=0, shapeIR=0; double te_delay1, te_delay2, tr_delay, ti_delay = 0; double del1=0, del2=0, del3=0, del4=0; double tau1=0, tau2=0, difftime=0, tetime=0; int table=0; /* Diffusion parameters */ #define MAXDIR 1024 /* Will anybody do more than 1024 directions or b-values? */ double roarr[MAXDIR], pearr[MAXDIR], slarr[MAXDIR]; int nbval, /* Total number of bvalues*directions */ nbro, nbpe, nbsl, i; double bro[MAXDIR], bpe[MAXDIR], bsl[MAXDIR], /* b-values along RO, PE, SL */ brs[MAXDIR], brp[MAXDIR], bsp[MAXDIR], /* and the cross-terms */ btrace[MAXDIR], /* and the trace */ max_bval=0, dcrush, dgss2, /* "delta" for crusher and gss2 gradients */ Dro, Dcrush, Dgss2; /* "DELTA" for readout, crusher and gss2 gradients */ /* Real-time variables ************************************/ int vpe_steps = v1; int vpe_ctr = v2; int vms_slices = v3; int vms_ctr = v4; int vpe_offset = v5; int vpe_index = v6; int vph180 = v7; // Phase of 180 pulse int vph2 = v8; // alternate phase of 180 on odd transients /* Initialize paramaters *********************************/ init_mri(); /* Check for external PE table ***************************/ if (strcmp(petable,"n") && strcmp(petable,"N") && strcmp(petable,"")) { loadtable(petable); table = 1; } if ((diff[0] == 'y') && (gcrush < 4)) warn_message("Advisory: set gcrush to higher value to avoid image artifacts"); /* Initialize gradient structures *************************/ init_rf(&p1_rf,p1pat,p1,flip1,rof1,rof2); init_rf(&p2_rf,p2pat,p2,flip2,rof2,rof2); init_slice(&ss_grad,"ss",thk); init_slice_butterfly(&ss2_grad,"ss2",thk*1.1,gcrush,tcrush); init_slice_refocus(&ssr_grad,"ssr"); init_readout_butterfly(&ro_grad,"ro",lro,np,sw,gcrushro,tcrushro); init_readout_refocus(&ror_grad,"ror"); init_phase(&pe_grad,"pe",lpe,nv); /* RF Calculations ****************************************/ calc_rf(&p1_rf,"tpwr1","tpwr1f"); calc_rf(&p2_rf,"tpwr2","tpwr2f"); if (p2_rf.header.rfFraction != 0.5) abort_message("RF pulse for refocusing (%s) must be symmetric",p2pat); /* Gradient calculations **********************************/ calc_slice(&ss_grad,&p1_rf,WRITE,"gss"); calc_slice(&ss2_grad,&p2_rf,WRITE,"gss2"); calc_slice_refocus(&ssr_grad, &ss_grad, NOWRITE,"gssr"); calc_readout(&ro_grad, WRITE, "gro","sw","at"); ro_grad.m0ref *= grof; calc_readout_refocus(&ror_grad, &ro_grad, NOWRITE, "gror"); calc_phase(&pe_grad, NOWRITE, "gpe","tpe"); /* Equalize refocus and PE gradient durations *************/ calc_sim_gradient(&ror_grad, &pe_grad, &ssr_grad,0,WRITE); /* Set up diffusion gradient */ if (diff[0] == 'y') { init_generic(&diff_grad,"diff",gdiff,tdelta); calc_generic(&diff_grad,NOWRITE,"",""); /* adjust duration, so tdelta is from start ramp up to start ramp down */ if (ix == 1) diff_grad.duration += diff_grad.tramp; calc_generic(&diff_grad,WRITE,"",""); } /* Min TE *************************************************/ tau1 = ss_grad.rfCenterBack + pe_grad.duration + 4e-6 + ss2_grad.rfCenterFront; tau2 = ss2_grad.rfCenterBack + ror_grad.duration + ro_grad.timeToEcho + alfa; temin = 2*(MAX(tau1,tau2) + 2*4e-6); /* have at least 4us between gradient events */ /* Calculate te_delays with the current TE, then later see how diffusion fits */ if ((minte[0] == 'y') || (te < temin)) { te_delay1 = temin/2 - tau1; te_delay2 = temin/2 - tau2; } else { te_delay1 = te/2 - tau1; te_delay2 = te/2 - tau2; } if (diff[0] =='y') { /* Is tDELTA long enough for RF refocusing gradient? */ if (tDELTA < diff_grad.duration + ss2_grad.duration) abort_message("DELTA too short, increase to %.2fms", (diff_grad.duration + ss2_grad.duration)*1000+0.005); /* Is tDELTA too long for TE dead time? */ difftime = tDELTA + diff_grad.duration; // tDELTA + front & back half diff_grad tetime = ss2_grad.duration + te_delay1 + te_delay2; if (difftime > tetime) { temin += (difftime - tetime); } } /* We now know the minimum TE incl. diffusion */ if (minte[0] == 'y') { te = temin; putvalue("te",ceil(te*1e6)*1e-6); /* round up to nearest us */ } if (te < temin) { if (diff[0] == 'n') { abort_message("TE too short. Minimum TE = %.2fms\n",temin*1000); } else { abort_message("TE too short, increase to %.2fms or reduce DELTA to %.2fms", temin*1000,(tetime-diff_grad.duration)*1000); } } te_delay1 = te/2 - tau1; te_delay2 = te/2 - tau2; /* Set up delays around diffusion gradients */ /* RF1 - del1 - diff - del2 - RF2 - del3 - diff - del4 - ACQ */ if (diff[0] == 'y') { del1 = (tetime - difftime)/2; del4 = del1; del2 = te_delay1 - diff_grad.duration; del3 = te_delay2 - diff_grad.duration; if (del3 < 0.0) { // shift diff block to right del1 += del3; del2 -= del3; del4 -= del3; del3 = 0; } else if (del2 < 0.0) { // shift diff block to left del1 -= del2; del3 -= del2; del4 += del2; del2 = 0; } } else { /* No diffusion */ del1 = 0; del3 = 0; del2 = te_delay1; del4 = te_delay2; } /* Min TR *************************************************/ trmin = (ss_grad.duration - ss_grad.rfCenterBack) + te + ro_grad.timeFromEcho; if (navigator[0] == 'y') trmin += (pe_grad.duration + ro_grad.duration); /* Optional prepulse calculations *************************/ if (sat[0] == 'y') { create_satbands(); trmin += satTime; } if (fsat[0] == 'y') { create_fatsat(); trmin += fsatTime; } if (mt[0] == 'y') { create_mtc(); trmin += mtTime; } if (ir[0] == 'y') { init_rf(&ir_rf,pipat,pi,flipir,rof2,rof2); calc_rf(&ir_rf,"tpwri","tpwrif"); init_slice_butterfly(&ssi_grad,"ssi",thk,gcrushir,tcrushir); calc_slice(&ssi_grad,&ir_rf,WRITE,"gssi"); tau1 = ss_grad.duration - ss_grad.rfCenterBack; /* duration of ss_grad before RF center */ ti_delay = ti - (ssi_grad.rfCenterBack + tau1); if (ti_delay < 0) { abort_message("TI too short, Minimum TI = %.2fms\n",(ti-ti_delay)*1000); } irTime = ti + ssi_grad.duration - ssi_grad.rfCenterBack; /* time to add to TR */ trmin += irTime; trmin -= tau1; /* but subtract out ss_grad which was already included in TR */ } trmin *= ns; if (mintr[0] == 'y'){ tr = trmin + ns*4e-6; putvalue("tr",tr); } if (tr < trmin) { abort_message("TR too short. Minimum TR= %.2fms\n",trmin*1000); } tr_delay = (tr - trmin)/ns > 4e-6 ? (tr - trmin)/ns : 4e-6; /***************************************************/ /* CALCULATE B VALUES ******************************/ if (diff[0] == 'y') { /* Get multiplication factors and make sure they have same # elements */ /* All this is only necessary because putCmd only work for ix==1 */ nbro = (int) getarray("dro",roarr); nbval = nbro; nbpe = (int) getarray("dpe",pearr); if (nbpe > nbval) nbval = nbpe; nbsl = (int) getarray("dsl",slarr); if (nbsl > nbval) nbval = nbsl; if ((nbro != nbval) && (nbro != 1)) abort_message("%s: Number of directions/b-values must be the same for all axes (readout)",seqfil); if ((nbpe != nbval) && (nbpe != 1)) abort_message("%s: Number of directions/b-values must be the same for all axes (phase)",seqfil); if ((nbsl != nbval) && (nbsl != 1)) abort_message("%s: Number of directions/b-values must be the same for all axes (slice)",seqfil); if (nbro == 1) for (i = 1; i < nbval; i++) roarr[i] = roarr[0]; if (nbpe == 1) for (i = 1; i < nbval; i++) pearr[i] = pearr[0]; if (nbsl == 1) for (i = 1; i < nbval; i++) slarr[i] = slarr[0]; } else { nbval = 1; roarr[0] = 0; pearr[0] = 0; slarr[0] = 0; } for (i = 0; i < nbval; i++) { /* Readout */ Dro = ror_grad.duration; bro[i] = bval(gdiff*roarr[i],tdelta,tDELTA); bro[i] += bval(ro_grad.amp,ro_grad.timeToEcho,Dro); /* Slice */ dgss2 = Dgss2 = ss_grad.rfCenterFront; dcrush = tcrush; //"delta" for crusher part of butterfly Dcrush = dcrush + ss_grad.rfDuration; //"DELTA" for crusher bsl[i] = bval(gdiff*slarr[i],tdelta,tDELTA); bsl[i] += bval(gcrush,dcrush,Dcrush); bsl[i] += bval(ss2_grad.ssamp,dgss2,Dgss2); bsl[i] += bval_nested(gdiff*slarr[i],tdelta,tDELTA,gcrush,dcrush,Dcrush); bsl[i] += bval_nested(gdiff*slarr[i],tdelta,tDELTA,ss2_grad.ssamp,dgss2,Dgss2); bsl[i] += bval_nested(gcrush,dcrush,Dcrush,ss2_grad.ssamp,dgss2,Dgss2); /* Phase */ bpe[i] = bval(gdiff*pearr[i],tdelta,tDELTA); /* Readout/Slice Cross-terms */ brs[i] = bval2(gdiff*roarr[i],gdiff*slarr[i],tdelta,tDELTA); brs[i] += bval_cross(gdiff*roarr[i],tdelta,tDELTA,gcrush,dcrush,Dcrush); brs[i] += bval_cross(gdiff*roarr[i],tdelta,tDELTA,ss2_grad.ssamp,dgss2,Dgss2); /* Readout/Phase Cross-terms */ brp[i] = bval2(gdiff*roarr[i],gdiff*pearr[i],tdelta,tDELTA); /* Slice/Phase Cross-terms */ bsp[i] = bval2(gdiff*slarr[i],gdiff*pearr[i],tdelta,tDELTA); bsp[i] += bval_cross(gdiff*pearr[i],tdelta,tDELTA,gcrush,dcrush,Dcrush); bsp[i] += bval_cross(gdiff*pearr[i],tdelta,tDELTA,ss2_grad.ssamp,dgss2,Dgss2); btrace[i] = (bro[i]+bsl[i]+bpe[i]); if (max_bval < btrace[i]) { max_bval = (bro[i]+bsl[i]+bpe[i]); } } /* End for-all-directions */ putarray("bvalrr",bro,nbval); putarray("bvalpp",bpe,nbval); putarray("bvalss",bsl,nbval); putarray("bvalrp",brp,nbval); putarray("bvalrs",brs,nbval); putarray("bvalsp",bsp,nbval); putarray("bvalue",btrace,nbval); putvalue("max_bval",max_bval); /* Generate phase-ramped pulses: 90, 180, and IR */ offsetlist(pss,ss_grad.ssamp,0,freq90,ns,seqcon[1]); shape90 = shapelist(p1pat,ss_grad.rfDuration,freq90,ns,0,seqcon[1]); offsetlist(pss,ss2_grad.ssamp,0,freq180,ns,seqcon[1]); shape180 = shapelist(p2pat,ss2_grad.rfDuration,freq180,ns,0,seqcon[1]); if (ir[0] == 'y') { offsetlist(pss,ssi_grad.ssamp,0,freqIR,ns,seqcon[1]); shapeIR = shapelist(pipat,ssi_grad.rfDuration,freqIR,ns,0,seqcon[1]); } /* Set pe_steps for profile or full image **********/ pe_steps = prep_profile(profile[0],nv,&pe_grad,&null_grad); initval(pe_steps/2.0,vpe_offset); sgl_error_check(sglerror); /* Return parameters to VnmrJ */ putvalue("rgss",ss_grad.tramp); //90 slice ramp if (ss2_grad.enableButterfly) { //180 slice ramps putvalue("rcrush",ss2_grad.crusher1RampToCrusherDuration); putvalue("rgss2",ss2_grad.crusher1RampToSsDuration); } else { putvalue("rgss2",ss2_grad.tramp); } if (ro_grad.enableButterfly) { putvalue("rgro",ro_grad.crusher1RampToSsDuration); } else { putvalue("rgro",ro_grad.tramp); //RO ramp } putvalue("tror",ror_grad.duration); //ROR duration putvalue("rgror",ror_grad.tramp); //ROR ramp putvalue("gpe",pe_grad.peamp); //PE max amp putvalue("gss",ss_grad.ssamp); putvalue("gro",ro_grad.roamp); g_setExpTime(tr*(nt*pe_steps*arraydim + ssc)); /* PULSE SEQUENCE *************************************/ rotate(); obsoffset(resto); roff = -poffset(pro,ro_grad.roamp); delay(4e-6); /* Begin phase-encode loop ****************************/ peloop(seqcon[2],pe_steps,vpe_steps,vpe_ctr); /* Read external kspace table if set ******************/ if (table) getelem(t1,vpe_ctr,vpe_index); else sub(vpe_ctr,vpe_offset,vpe_index); settable(t2,2,ph180); // initialize phase tables and variables getelem(t2,vpe_ctr,vph180); add(oph,vph180,vph180); // 180 deg pulse phase alternates +/- 90 from receiver mod2(ct,vph2); dbl(vph2,vph2); add(vph180,vph2,vph180); // Alternate phase for 180 on odd transients /* Begin multislice loop ******************************/ msloop(seqcon[1],ns,vms_slices,vms_ctr); if (ticks) { xgate(ticks); grad_advance(gpropdelay); } /* TTL scope trigger **********************************/ sp1on(); delay(5e-6); sp1off(); /* Prepulses ******************************************/ if (sat[0] == 'y') satbands(); if (fsat[0] == 'y') fatsat(); if (mt[0] == 'y') mtc(); /* Optional IR pulse **********************************/ if (ir[0] == 'y') { obspower(ir_rf.powerCoarse); obspwrf(ir_rf.powerFine); delay(4e-6); obl_shapedgradient(ssi_grad.name,ssi_grad.duration,0,0,ssi_grad.amp,NOWAIT); delay(ssi_grad.rfDelayFront); shapedpulselist(shapeIR,ssi_grad.rfDuration,oph,rof1,rof2,seqcon[1],vms_ctr); delay(ssi_grad.rfDelayBack); delay(ti_delay); } /* Slice select RF pulse ******************************/ obspower(p1_rf.powerCoarse); obspwrf(p1_rf.powerFine); delay(4e-6); obl_shapedgradient(ss_grad.name,ss_grad.duration,0,0,ss_grad.amp,NOWAIT); delay(ss_grad.rfDelayFront); shapedpulselist(shape90,ss_grad.rfDuration,oph,rof1,rof2,seqcon[1],vms_ctr); delay(ss_grad.rfDelayBack); /* Phase encode, refocus, and dephase gradient ********/ pe_shapedgradient(pe_grad.name,pe_grad.duration,0,0,-ssr_grad.amp, pe_grad.increment,vpe_index,WAIT); delay(del1); // delay to start of first diffusion gradient if (diff[0] == 'y') { obl_shapedgradient(diff_grad.name,diff_grad.duration, diff_grad.amp*dro,diff_grad.amp*dpe,diff_grad.amp*dsl,WAIT); } delay(del2); // delay from end of diffusion to slice refocusing /* Refocusing RF pulse ********************************/ obspower(p2_rf.powerCoarse); obspwrf(p2_rf.powerFine); delay(4e-6); obl_shapedgradient(ss2_grad.name,ss2_grad.duration,0,0,ss2_grad.amp,NOWAIT); delay(ss2_grad.rfDelayFront); shapedpulselist(shape180,ss2_grad.rfDuration,vph180,rof2,rof2,seqcon[1],vms_ctr); delay(ss2_grad.rfDelayBack); delay(del3); // delay from slice refocusing to second diffusion gradient if (diff[0] == 'y') { obl_shapedgradient(diff_grad.name,diff_grad.duration, diff_grad.amp*dro,diff_grad.amp*dpe,diff_grad.amp*dsl,WAIT); } delay(del4); // delay from end of diffusion gradient to readout event /* Readout gradient and acquisition ********************/ roff = -poffset(pro,ro_grad.roamp); obl_shapedgradient(ror_grad.name,ror_grad.duration,-ror_grad.amp,0,0,WAIT); obl_shapedgradient(ro_grad.name,ro_grad.duration,ro_grad.amp,0,0,NOWAIT); delay(ro_grad.atDelayFront); startacq(alfa); acquire(np,1.0/sw); delay(ro_grad.atDelayBack); endacq(); /* Rewind Phase encoding ******************************/ pe_shapedgradient(pe_grad.name,pe_grad.duration,0,0,0, pe_grad.increment,vpe_index,WAIT); if (navigator[0] == 'y') { roff = -poffset(pro,-ro_grad.roamp); obl_shapedgradient(ro_grad.name,ro_grad.duration,-ro_grad.amp,0,0,NOWAIT); delay(ro_grad.atDelayFront); startacq(alfa); acquire(np,1.0/sw); delay(ro_grad.atDelayBack); endacq(); } /* Relaxation delay ***********************************/ delay(tr_delay); endmsloop(seqcon[1],vms_ctr); endpeloop(seqcon[2],vpe_ctr); }
pulsesequence() { /* Internal variable declarations *************************/ int shapelist90,shapelist180; int table = 0; double tau1,tau2,tau3,te1_delay,te2_delay,te3_delay,tr_delay; double freq90[MAXNSLICE],freq180[MAXNSLICE]; double thk2fact,crush_step,neby2,crush_ind; int suppressSTE,*crushtab; char crushmod[MAXSTR]; int i; /* Real-time variables used in this sequence **************/ int vpe_steps = v1; // Number of PE steps int vpe_ctr = v2; // PE loop counter int vpe_mult = v3; // PE multiplier, ranges from -PE/2 to PE/2 int vpe_offset = v4; // PE/2 for non-table offset int vms_slices = v5; // Number of slices int vms_ctr = v6; // Slice loop counter int vne = v7; // Number of echoes int vne_ctr = v8; // Echo loop counter int vssc = v9; // Compressed steady-states int vtrimage = v10; // Counts down from nt, trimage delay when 0 int vacquire = v11; // Argument for setacqvar, to skip steady state acquires int vphase90 = v12; // Phase of 90 degree excitation pulse int vphase180 = v13; // Phase of 180 degree refocusing pulse int vphindex = v14; // Phase cycle index int vneindex = v15; // Echo index, odd or even int vcrush = v16; // Crusher modulation int vtrigblock = v17; // Number of slices per trigger block /* Initialize paramaters **********************************/ init_mri(); getstr("crushmod",crushmod); suppressSTE=getval("suppressSTE"); /* Load external PE table ********************************/ if (strcmp(petable,"n") && strcmp(petable,"N") && strcmp(petable,"")) { loadtable(petable); table = 1; } /* RF Power & Bandwidth Calculations **********************/ shape_rf(&p1_rf,"p1",p1pat,p1,flip1,rof1,rof2); shape_rf(&p2_rf,"p2",p2pat,p2,flip2,rof1,rof2); calc_rf(&p1_rf,"tpwr1","tpwr1f"); calc_rf(&p2_rf,"tpwr2","tpwr2f"); /* Calculate thk2fact to ensure gss=gss2 for the choice of p1 and p2 so that the sequence remains robust in the absence of correct balancing of slice select and slice refocus gradients */ thk2fact=p2_rf.bandwidth/p1_rf.bandwidth; putvalue("thk2fact",thk2fact); /* Initialize gradient structures *************************/ init_readout(&ro_grad,"ro",lro,np,sw); ro_grad.pad1=alfa; ro_grad.pad2=alfa; init_readout_refocus(&ror_grad,"ror"); init_phase(&pe_grad,"pe",lpe,nv); init_slice(&ss_grad,"ss",thk); init_slice(&ss2_grad,"ss2",thk*thk2fact); init_slice_refocus(&ssr_grad,"ssr"); init_generic(&crush_grad,"crush",gcrush,tcrush); /* Gradient calculations **********************************/ calc_readout(&ro_grad,WRITE,"gro","sw","at"); calc_readout_refocus(&ror_grad,&ro_grad,NOWRITE,"gror"); calc_phase(&pe_grad,WRITE,"gpe","tpe"); calc_slice(&ss_grad,&p1_rf,WRITE,"gss"); calc_slice(&ss2_grad,&p2_rf,WRITE,""); calc_slice_refocus(&ssr_grad,&ss_grad,NOWRITE,"gssr"); calc_generic(&crush_grad,WRITE,"",""); /* Equalize slice refocus and PE gradient durations *******/ calc_sim_gradient(&ror_grad,&null_grad,&ssr_grad,0.0,WRITE); /* Create optional prepulse events ************************/ if (sat[0] == 'y') create_satbands(); if (fsat[0] == 'y') create_fatsat(); if (mt[0] == 'y') create_mtc(); if (ir[0] == 'y') create_inversion_recovery(); sgl_error_check(sglerror); /* Set up frequency offset pulse shape list ********/ offsetlist(pss,ss_grad.amp,0,freq90,ns,seqcon[1]); offsetlist(pss,ss2_grad.ssamp,0,freq180,ns,seqcon[1]); shapelist90 = shapelist(p1_rf.pulseName,ss_grad.rfDuration,freq90,ns,ss_grad.rfFraction,seqcon[1]); shapelist180 = shapelist(p2_rf.pulseName,ss2_grad.rfDuration,freq180,ns,ss2_grad.rfFraction,seqcon[1]); /* To ensure proper overlap spin and stimulated echoes ensure that the middle of the refocusing RF pulse is the centre of the pulse and that echoes are formed in the centre of the acquisition window */ if (ss2_grad.rfFraction != 0.5) abort_message("ERROR %s: Refocusing RF pulse must be symmetric (RF fraction = %.2f)", seqfil,ss2_grad.rfFraction); if (ro_grad.echoFraction != 1) abort_message("ERROR %s: Echo Fraction must be 1",seqfil); /* Find sum of all events in each half-echo period ********/ tau1 = ss_grad.rfCenterBack + ssr_grad.duration + crush_grad.duration + ss2_grad.rfCenterFront; tau2 = ss2_grad.rfCenterBack + pe_grad.duration + crush_grad.duration + ro_grad.timeToEcho; tau3 = ro_grad.timeFromEcho + pe_grad.duration + crush_grad.duration + ss2_grad.rfCenterFront; espmin = 2*MAX(MAX(tau1,tau2),tau3); // Minimum echo spacing espmin += 2*GRADIENT_RES; // Ensure that each delay is at least GRADIENT_RES te = granularity(te,2*GRADIENT_RES); if (minesp[0] == 'y') { te = espmin; putvalue("te",te); } if (FP_LT(te,espmin)) { abort_message("ERROR %s: Echo time too small, minimum is %.3fms\n",seqfil,espmin*1000); } te1_delay = te/2.0 - tau1; // Intra-esp delays te2_delay = te/2.0 - tau2; te3_delay = te/2.0 - tau3; /* Now set the TE processing array accordingly */ putCmd("TE = 0"); /* Re-initialize TE */ for (i=0;i<ne;i++) putCmd("TE[%d] = %f",i+1,te*1000*(i+1)); /* Check nsblock, the number of slices blocked together (used for triggering and/or inversion recovery) */ check_nsblock(); /* Minimum TR **************************************/ trmin = ss_grad.rfCenterFront + ne*te + ro_grad.timeFromEcho + pe_grad.duration + te3_delay + 2*GRADIENT_RES; /* Increase TR if any options are selected *********/ if (sat[0] == 'y') trmin += satTime; if (fsat[0] == 'y') trmin += fsatTime; if (mt[0] == 'y') trmin += mtTime; if (ticks > 0) trmin += GRADIENT_RES; /* Adjust for all slices ***************************/ trmin *= ns; /* Inversion recovery *********************************/ if (ir[0] == 'y') { /* tauti is the additional time beyond IR component to be included in ti */ /* satTime, fsatTime and mtTime all included as those modules will be after IR */ tauti = satTime + fsatTime + mtTime + GRADIENT_RES + ss_grad.rfCenterFront; /* calc_irTime checks ti and returns the time of all IR components */ trmin += calc_irTime(tauti,trmin,mintr[0],tr,&trtype); } if (mintr[0] == 'y') { tr = trmin; putvalue("tr",tr); } if (FP_LT(tr,trmin)) { abort_message("ERROR %s: TR too short, minimum TR is %.3fms\n",seqfil,trmin*1000); } /* Calculate tr delay */ tr_delay = granularity((tr-trmin)/ns,GRADIENT_RES); /* Set pe_steps for profile or full image **********/ pe_steps = prep_profile(profile[0],nv,&pe_grad,&per_grad); F_initval(pe_steps/2.0,vpe_offset); /* Shift DDR for pro ************************************/ roff = -poffset(pro,ro_grad.roamp); /* Adjust experiment time for VnmrJ *********************/ if (ssc<0) { if (seqcon[2] == 'c') g_setExpTime(trmean*(ntmean*pe_steps*arraydim - ssc*arraydim)); else g_setExpTime(trmean*(ntmean*pe_steps*arraydim - ssc*pe_steps*arraydim)); } else g_setExpTime(trmean*ntmean*pe_steps*arraydim + tr*ssc); /* Set phase cycle tables */ if (suppressSTE) { if ((int)nt%2 == 1) abort_message("STE suppression requires a 2 step phase cycle. Set nt as a multiple of 2\n"); settable(t2,4,phref1s); settable(t3,4,phref2s); settable(t4,4,phrec1s); settable(t5,4,phrec2s); } else { settable(t2,4,phref1); settable(t3,4,phref2); settable(t4,4,phrec1); settable(t5,4,phrec2); } /* Set crusher table */ crushtab=malloc((int)ne*sizeof(int)); neby2=ceil(ne/2.0 - US); // US to handle precision errors crush_step=gcrush/neby2; for (i=0; i<ne; i++) { crush_ind = (1.0-2.0*(i%2))*(neby2-floor(i/2)); crushtab[i] = (int)(crush_ind); } settable(t6,(int)ne,crushtab); /* PULSE SEQUENCE ***************************************/ status(A); rotate(); triggerSelect(trigger); // Select trigger input 1/2/3 obsoffset(resto); delay(GRADIENT_RES); initval(fabs(ssc),vssc); // Compressed steady-state counter if (seqcon[2]=='s') assign(zero,vssc); // Zero for standard peloop assign(one,vacquire); // real-time acquire flag setacqvar(vacquire); // Turn on acquire when vacquire is zero /* Phase for excitation pulse */ assign(zero,vphase90); /* trigger */ if (ticks > 0) F_initval((double)nsblock,vtrigblock); /* Begin phase-encode loop ****************************/ peloop(seqcon[2],pe_steps,vpe_steps,vpe_ctr); if (trtype) delay(ns*tr_delay); // relaxation delay /* Compressed steady-states: 1st array & transient, all arrays if ssc is negative */ if ((ix > 1) && (ssc > 0)) assign(zero,vssc); sub(vpe_ctr,vssc,vpe_ctr); // vpe_ctr counts up from -ssc assign(zero,vssc); if (seqcon[2] == 's') assign(zero,vacquire); // Always acquire for non-compressed loop else { ifzero(vpe_ctr); assign(zero,vacquire); // Start acquiring when vpe_ctr reaches zero endif(vpe_ctr); } /* Read external kspace table if set ******************/ if (table) getelem(t1,vpe_ctr,vpe_mult); else { ifzero(vacquire); sub(vpe_ctr,vpe_offset,vpe_mult); elsenz(vacquire); sub(zero,vpe_offset,vpe_mult); // Hold PE mult at initial value for steady states endif(vacquire); } msloop(seqcon[1],ns,vms_slices,vms_ctr); if (!trtype) delay(tr_delay); // Relaxation delay if (ticks > 0) { modn(vms_ctr,vtrigblock,vtest); ifzero(vtest); // if the beginning of an trigger block xgate(ticks); grad_advance(gpropdelay); delay(GRADIENT_RES); elsenz(vtest); delay(GRADIENT_RES); endif(vtest); } sp1on(); delay(GRADIENT_RES); sp1off(); // Scope trigger /* Prepulse options ***********************************/ if (ir[0] == 'y') inversion_recovery(); if (sat[0] == 'y') satbands(); if (fsat[0] == 'y') fatsat(); if (mt[0] == 'y') mtc(); /* 90 degree pulse ************************************/ obspower(p1_rf.powerCoarse); obspwrf(p1_rf.powerFine); delay(GRADIENT_RES); obl_shapedgradient(ss_grad.name,ss_grad.duration,0,0,ss_grad.amp,NOWAIT); delay(ss_grad.rfDelayFront); shapedpulselist(shapelist90,ss_grad.rfDuration,vphase90,rof1,rof2,seqcon[1],vms_ctr); delay(ss_grad.rfDelayBack); /* Slice refocus **************************************/ obl_shapedgradient(ssr_grad.name,ssr_grad.duration,ror_grad.amp,0.0,-ssr_grad.amp,WAIT); /* First half-TE delay ********************************/ obspower(p2_rf.powerCoarse); obspwrf(p2_rf.powerFine); delay(te1_delay); F_initval(ne,vne); loop(vne,vne_ctr); /* Phase cycle for refocusing pulse and receiver */ mod4(ct,vphindex); mod2(vne_ctr,vneindex); ifzero(vneindex); getelem(t2,vphindex,vphase180); getelem(t4,vphindex,oph); elsenz(vneindex); getelem(t3,vphindex,vphase180); getelem(t5,vphindex,oph); endif(vneindex); /* Crusher gradient modulation */ assign(one,vcrush); if (crushmod[0] == 'y') { assign(zero,vcrush); ifzero(vneindex); add(vcrush,one,vcrush); elsenz(vneindex); sub(vcrush,one,vcrush); endif(vneindex); } if (crushmod[0] == 'p') { getelem(t6,vne_ctr,vcrush); crush_grad.amp=crush_step; } /* 180 degree pulse *******************************/ if (crushmod[0] == 'y' || crushmod[0] == 'p') var3_shapedgradient(crush_grad.name,crush_grad.duration,0.0,0.0,0.0,0.0,0.0,crush_grad.amp,zero,zero,vcrush,WAIT); else obl_shapedgradient(crush_grad.name,crush_grad.duration,crush_grad.amp,0,crush_grad.amp,WAIT); obl_shapedgradient(ss2_grad.name,ss2_grad.duration,0,0,ss2_grad.amp,NOWAIT); delay(ss2_grad.rfDelayFront); shapedpulselist(shapelist180,ss2_grad.rfDuration,vphase180,rof1,rof2,seqcon[1],vms_ctr); delay(ss2_grad.rfDelayBack); if (crushmod[0] == 'y' || crushmod[0] == 'p') var3_shapedgradient(crush_grad.name,crush_grad.duration,0.0,0.0,0.0,0.0,0.0,crush_grad.amp,zero,zero,vcrush,WAIT); else obl_shapedgradient(crush_grad.name,crush_grad.duration,crush_grad.amp,0,crush_grad.amp,WAIT); /* Second half-TE period ******************************/ delay(te2_delay); /* Phase-encode gradient ******************************/ pe_shapedgradient(pe_grad.name,pe_grad.duration,0,0,0,-pe_grad.increment,vpe_mult,WAIT); /* Readout gradient ************************************/ obl_shapedgradient(ro_grad.name,ro_grad.duration,ro_grad.roamp,0,0,NOWAIT); delay(ro_grad.atDelayFront-alfa); /* Acquire data ****************************************/ startacq(alfa); acquire(np,1.0/sw); endacq(); delay(ro_grad.atDelayBack); /* Rewinding phase-encode gradient ********************/ pe_shapedgradient(pe_grad.name,pe_grad.duration,0,0,0,pe_grad.increment,vpe_mult,WAIT); /* Second half-TE delay *******************************/ delay(te3_delay); endloop(vne_ctr); endmsloop(seqcon[1],vms_ctr); endpeloop(seqcon[2],vpe_ctr); /* Inter-image delay **********************************/ sub(ntrt,ct,vtrimage); decr(vtrimage); ifzero(vtrimage); delay(trimage); endif(vtrimage); }