CT CT UrographyUrography Update: Update: CTU, MRU or Nothing?CTU, MRU or Nothing?Stuart G. Silverman, M.D., FACRStuart G. Silverman, M.D., FACR

Professor of RadiologyProfessor of RadiologyHarvard Medical SchoolHarvard Medical School

Director, Abdominal Imaging and InterventionDirector, Abdominal Imaging and InterventionBrigham and WomenBrigham and Women’’s Hospitals Hospital

Boston, MABoston, MA

CT CT UrographyUrography Update: Update: CTU, MRU or Nothing?CTU, MRU or Nothing?Stuart G. Silverman, M.D., FACRStuart G. Silverman, M.D., FACR

DisclosuresDisclosuresGalilGalil Medical Ltd. Medical Ltd. YokneamYokneam, Israel , Israel –– ConsultantConsultantLippincott, Williams, and Wilkins Philadelphia, PA Lippincott, Williams, and Wilkins Philadelphia, PA –– Book Book RoyaltiesRoyalties

Urinary Tract CT ProtocolsUrinary Tract CT Protocols•• Flank pain Flank pain -- > UP (> UP (““Stone protocolStone protocol””))•• Renal mass Renal mass -- > UP, NP, Excretory (Kidney)> UP, NP, Excretory (Kidney)•• Congenital anomalies Congenital anomalies -- > Excretory> Excretory•• Partial Partial nephrectomynephrectomy -- > AP, VP, Excretory> AP, VP, Excretory•• PostPost--operative Complication operative Complication -- > Excretory> Excretory•• Trauma Trauma --> NP, Excretory> NP, ExcretoryUP = unenhanced phase; NP = UP = unenhanced phase; NP = nephrographicnephrographic phasephaseAP = arterial phase; VP = venous phase AP = arterial phase; VP = venous phase

BWH CTU ProtocolsBWH CTU Protocols

•• Three phase Three phase –– UP (abdomen and pelvis), NP UP (abdomen and pelvis), NP (kidneys only), EP (abdomen and pelvis), (kidneys only), EP (abdomen and pelvis), supplemented with 10 mg supplemented with 10 mg furosemidefurosemide IVIV

Patients > 40 years oldPatients > 40 years old

•• Split bolus, two phase Split bolus, two phase –– abdomen and abdomen and pelvis, supplemented with 250 cc saline IVpelvis, supplemented with 250 cc saline IV

Patients Patients << 40 years old40 years old

10 mg 10 mg IV Furosemide 22--33”” CM (100cc)

UnenhancedUnenhanced NephrographicNephrographic ExcretoryExcretoryRangeRange Abd/PelAbd/Pel KidneysKidneys Abd/PelAbd/PelDelay Delay ---- 100 s 100 s 10 10 -- 15 min15 minCollimation Collimation 1.2 mm 1.2 mm 1.2 mm 1.2 mm 0.6 mm0.6 mmAxial Recon/Axial Recon/IncrIncr 3/3 3/1.5 3/3 3/1.5 3/33/3Post Processing Post Processing ---- ---- CorCor / Sag / MIP / CPR / VR/ Sag / MIP / CPR / VR

Iodinated contrast material (300 Iodinated contrast material (300 mgImgI/ml); 0.5 s rotation time/ml); 0.5 s rotation timeAEC w/ quality reference 200 AEC w/ quality reference 200 mAsmAs, 120 , 120 kVpkVp

BWH CT Urography Protocol64 64 –– ChannelChannel MDCT with 3 phasesMDCT with 3 phases

Silverman et al Radiology 2006Silverman et al Radiology 2006

BWH CTU Protocol for pts < 40 y.o.BWH CTU Protocol for pts < 40 y.o.

Split dose Split dose 370 370 mgImgI/ml/ml CM (40cc) (80 cc)UnenhancedUnenhanced NPNP + + EPEP

RangeRange Abd/PelAbd/Pel Abd/PelAbd/PelDelay Delay ---- 6 min6 min 100 sec100 secCollimation 2.5 mm Collimation 2.5 mm 2.5 mm2.5 mmAxial Recon/Axial Recon/IncrIncr 3/3 3/3 3/33/3Post Processing Post Processing ---- CorCor / Sag / MIP / CPR / VR/ Sag / MIP / CPR / VR

Modified from Chow and Modified from Chow and SommerSommer AJR 2001AJR 2001

SalineSaline

Obtaining NP and PP during one Obtaining NP and PP during one scan reduces radiation dosescan reduces radiation dose

BWH MRU BWH MRU –– Bladder FocusBladder Focus•• Sag Single Shot FSE (HASTE or SSFSE) Sag Single Shot FSE (HASTE or SSFSE) -- pelvispelvis•• Sag, Sag, CorCor, Ax T2W FSE , Ax T2W FSE -- pelvispelvis•• CorCor Single Shot FSE FS 20mm BH Single Shot FSE FS 20mm BH -- uretersureters•• Sag, Sag, CorCor 3D GRE (LAVA or VIBE) FS 3D GRE (LAVA or VIBE) FS -- pelvispelvis•• Inject 10 mg IV Inject 10 mg IV FurosemideFurosemide (or 250 cc NS at start)(or 250 cc NS at start)•• Ax 3D GRE FS PreAx 3D GRE FS Pre-- pelvispelvis•• Inject CM, then Ax 3D GRE FS x 3 Inject CM, then Ax 3D GRE FS x 3 -- pelvispelvis•• Sag, Sag, CorCor 3D GRE FS 3D GRE FS -- pelvispelvis•• Ax 3D GRE FS Ax 3D GRE FS -- kidneyskidneys•• CorCor 3D GRE high FA 3D GRE high FA --uretersureters

Static FluidStatic FluidMRU Pre MRU Pre

ExcretoryExcretoryPhasePhase

MRU Post ContrastMRU Post Contrast““IVP delayedIVP delayed””

BWH MRU BWH MRU –– Kidney FocusKidney Focus•• Sag, Sag, CorCor, Ax Single Shot (HASTE or SSFSE) , Ax Single Shot (HASTE or SSFSE) -- kidneykidney•• Sag, Sag, CorCor, Ax T2W FSE , Ax T2W FSE -- kidneykidney•• Ax T1 Dual Echo In/Out of Phase Ax T1 Dual Echo In/Out of Phase -- kidneykidney•• Ax DWI (0/250/500/1000 or 0/500) Ax DWI (0/250/500/1000 or 0/500) -- kidneykidney•• CorCor Single Shot FSE FS 20mm BH Single Shot FSE FS 20mm BH -- uretersureters•• Inject 10 mg IV Inject 10 mg IV FurosemideFurosemide (or 250 cc NS at start)(or 250 cc NS at start)•• Ax 3D GRE (LAVA or VIBE) FS Pre Ax 3D GRE (LAVA or VIBE) FS Pre -- kidneykidney•• InjInj CM, then Ax 3D GRE FS Post x3CM, then Ax 3D GRE FS Post x3-- kidneykidney•• Ax 3D GRE FS Ax 3D GRE FS -- pelvispelvis•• CorCor 3D GRE high FA 3D GRE high FA –– uretersureters

Static FluidStatic FluidMRU PreMRU Pre

ExcretoryExcretoryMRUMRU

MRU Post ContrastMRU Post Contrast““IVP delayedIVP delayed””

CTU CTU vsvs IVU (N=74)IVU (N=74)

0%5%

10%15%20%25%30%35%40%45%

Only CTU >75%CTU 50% CTU >75% IVU All IVU

7 of 10 members 7 of 10 members of SUR use CTUof SUR use CTUmore than 75% more than 75% of time to imageof time to imageurinary tracturinary tract

Townsend et al, JCAT 2009Townsend et al, JCAT 200926% use CTU exclusively26% use CTU exclusively

•• CTU is a sensitive, accurate, and CTU is a sensitive, accurate, and comprehensive exam of the urinary tract.comprehensive exam of the urinary tract.

•• CTU is available, safe, wellCTU is available, safe, well--tolerated, and tolerated, and reproducible.reproducible.

What are the Issues?What are the Issues?What is good about CTU?What is good about CTU?

•• CTU results in substantial radiation dose CTU results in substantial radiation dose (15 (15 mSvmSv or more) to patients. or more) to patients.

•• CTU is costly.CTU is costly.

What is bad about CTU?What is bad about CTU?

Indications: CT Indications: CT UrographyUrography•• HydronephrosisHydronephrosis ?etiology?etiology•• HematuriaHematuria•• Suspected Suspected urothelialurothelial cancer cancer

(e.g., positive urine cytology)(e.g., positive urine cytology)•• FollowFollow--up up urothelialurothelial cancercancer•• Others (Others (egeg, pre/post ablation), pre/post ablation)

Differential Diagnosis of Asymptomatic Differential Diagnosis of Asymptomatic Microscopic Microscopic HematuriaHematuria

Life ThreateningLife ThreateningMalignancy, AAAMalignancy, AAA

Significant Requiring TreatmentSignificant Requiring TreatmentUrolithiasisUrolithiasis, BPH with , BPH with SxSx, VUR, UPJ obstruction, , VUR, UPJ obstruction, RAS, RVT, infectionRAS, RVT, infection

Significant Requiring ObservationSignificant Requiring ObservationBPH without BPH without SxSx, papillary necrosis, trauma, AVF, papillary necrosis, trauma, AVF

InsignificantInsignificantRenal cyst, exercise, polyps, Renal cyst, exercise, polyps, urethritisurethritis, , urethrotrigonitisurethrotrigonitis

Modified from Modified from GrossfeldGrossfeld and Carroll, UCNA 1998and Carroll, UCNA 1998

HematuriaHematuria -- Yield varies by TypeYield varies by Type•• Gross Gross hematuriahematuria

23% have urologic cancers 23% have urologic cancers •• Microscopic Microscopic hematuriahematuria, defined as , defined as ≥≥ 3 3

RBCsRBCs / / hpfhpf, is present in 9, is present in 9--18% 18% normalsnormals ((MaccioniMaccioni, 1989), 1989)

•• PPV of microscopic PPV of microscopic hematuriahematuria typically typically in the 20in the 20--30% range 30% range

(Woodlander JAMA 1989)(Woodlander JAMA 1989)

Asymptomatic Asymptomatic HematuriaHematuria““No data exist showing the impact No data exist showing the impact of IVU, of IVU, ultrasonographyultrasonography, CT or MRI , CT or MRI on the management of patients on the management of patients with microscopic with microscopic hematuriahematuria. . Therefore, evidenceTherefore, evidence--based imaging based imaging guidelines cannot be formulated.guidelines cannot be formulated.””

AUA recommendations: AUA recommendations: GrossfeldGrossfeld et al, Urology 2001et al, Urology 2001

Risk Factors for Urologic DiseaseRisk Factors for Urologic Disease•• Age > 40 yearsAge > 40 years•• SmokingSmoking•• Gross Gross hematuriahematuria•• IrritativeIrritative voiding symptomsvoiding symptoms•• Urinary tract infectionsUrinary tract infections•• Exposure to carcinogens: pelvic Exposure to carcinogens: pelvic

irradiation, analgesic abuse, irradiation, analgesic abuse, cyclophosphamidecyclophosphamide, chemicals/dyes , chemicals/dyes (benzenes, aromatic amines)(benzenes, aromatic amines)

AUA 2001: High Risk PatientsAUA 2001: High Risk Patients

Upper tract imaging, cytology, Upper tract imaging, cytology, cystoscopycystoscopy

GrossfeldGrossfeld, et al, Urology 2001, 57:604, et al, Urology 2001, 57:604--610610

OneOne positive urine sediment positive urine sediment >> 3RBC/hpf3RBC/hpf

If negative, repeat W/U every yr x 3 yrsIf negative, repeat W/U every yr x 3 yrs

AUA 2001: Low Risk PatientsAUA 2001: Low Risk Patients

Upper tract imaging, cytology, Upper tract imaging, cytology, cystoscopycystoscopy

GrossfeldGrossfeld, et al, Urology 2001, 57:604, et al, Urology 2001, 57:604--610610

2 of 32 of 3 positive urine sediments positive urine sediments >> 3RBC/hpf3RBC/hpf

If negative, further W/U optionalIf negative, further W/U optional

Imaging for Imaging for HematuriaHematuria: AUA : AUA ‘‘0101

Upper tract imaging recommendation:Upper tract imaging recommendation:

IVU or CTUIVU or CTU

GrossfeldGrossfeld, et al, Urology 2001, 57:604, et al, Urology 2001, 57:604--610610

Imaging for Imaging for HematuriaHematuria: ACR : ACR ‘‘0505ExamExam RatingRating CommentsCommentsCT CT UrographyUrography 88IVUIVU 8 8 US (renal/bladder)US (renal/bladder) 66 May miss May miss urothelialurothelial lesionslesionsRetro Retro PyelographyPyelography 55MR MR UrographyUrography 44CT (A/P)CT (A/P) 44 May follow IVU or USMay follow IVU or USAngiographyAngiography 44 To detect AVMTo detect AVMKUBKUB 22 May be coupled with USMay be coupled with USMRIMRI (A/P)(A/P) 22ScintigraphyScintigraphy 22Virtual Virtual cystoscopycystoscopy 22

ChoykeChoyke et al, ACR 2005et al, ACR 2005

Imaging Algorithm for Imaging Algorithm for HematuriaHematuriaMDCTUMDCTU

Renal cystRenal cyst Renal massRenal mass NormalNormal Urothelial Urothelial abnabn

Retro Retro PyelogramPyelogramMRIMRI

This algorithm is simpler, and This algorithm is simpler, and faster than when IVU was used faster than when IVU was used as the initial test for as the initial test for hematuriahematuria..

0

10

20

30

40

50

True Positive False Positive

4343 3939

82 (3%) positive CT 82 (3%) positive CT urogramsurograms (n=2602)(n=2602)

PPV: 43/82 = 52%PPV: 43/82 = 52% Wheeler S et al, SUR 2008Wheeler S et al, SUR 2008

Is CTU Good in Detecting UT TCC?Is CTU Good in Detecting UT TCC?

Wheeler S et al, SUR 2008Wheeler S et al, SUR 2008

Is CTU Good in Detecting UT TCC?Is CTU Good in Detecting UT TCC?

0

10

20

30

40

Large Mass(>5 mm)

Small Mass(</=5 mm)

UrothelialThickening

CTU + True +

36

29

17

0

29

14

PPV = 81%PPV = 81%

PPV = 0%PPV = 0%

PPV = 48%PPV = 48%

Imaging Algorithm for Imaging Algorithm for HematuriaHematuriaMDCTUMDCTU

Renal cystRenal cyst Renal massRenal mass NormalNormal Urothelial Urothelial abnabn

Retro Retro PyelogramPyelogramMRIMRI

Note.Note.-- Retrograde Retrograde pyelographypyelographymay still be needed when CTU may still be needed when CTU is positiveis positive……

Thickening?Thickening?

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Urothelial CA

GrossHematuria

MicroscopicHematuria 0.984, n=2490.984, n=249

0.971, n=3730.971, n=373

0.769, n=1580.769, n=158

Bladder Ca Detection (n=838)Bladder Ca Detection (n=838)Negative Predictive Value of CTUNegative Predictive Value of CTU

SadowSadow et al Radiology 2008et al Radiology 2008

AUA 2001: Low Risk PatientsAUA 2001: Low Risk Patients

CT CT urographyurography, cytology, , cytology, cystoscopycystoscopy

GrossfeldGrossfeld, et al, Urology 2001, 57:604, et al, Urology 2001, 57:604--610610

2 of 32 of 3 positive urine sediments positive urine sediments >> 3RBC/hpf3RBC/hpf

If negative, further W/U optionalIf negative, further W/U optional

Possibly Possibly in the in the

futurefuture……

CTU in pts < 40 w/ CTU in pts < 40 w/ HematuriaHematuria•• Significant findings found uncommonly Significant findings found uncommonly

[44 (22%) of 204][44 (22%) of 204]•• Of 44 significant causes found, 33 (75%) Of 44 significant causes found, 33 (75%)

were due to were due to urolithiasisurolithiasis•• All but 3 significant findings were seen on All but 3 significant findings were seen on

unenhancedunenhanced CT aloneCT alone•• All 3 cases had predisposing conditions!All 3 cases had predisposing conditions!•• 4 false positive CT 4 false positive CT urogramsurograms would not would not

have been found on have been found on unenhancedunenhanced CT CT SadowSadow et al RSNA 2007et al RSNA 2007

CTU in pts < 40 w/ CTU in pts < 40 w/ HematuriaHematuria

SadowSadow et al RSNA 2007et al RSNA 2007

Unless there is a predisposing Unless there is a predisposing condition, it may be appropriate condition, it may be appropriate to perform only to perform only unenhancedunenhanced CT CT in pts < 40 with in pts < 40 with hematuriahematuria

But more data are neededBut more data are needed……

•• I+ AP CT was adequate in diagnosing I+ AP CT was adequate in diagnosing local recurrence and distant local recurrence and distant metsmets

•• CTU was needed to diagnose urinary CTU was needed to diagnose urinary diversion malfunction or leakage.diversion malfunction or leakage.

•• CTU may be needed to diagnose UTT, CTU may be needed to diagnose UTT, but was not necessary in this series but was not necessary in this series --the prevalence of UTT (1/80, 1.5%) the prevalence of UTT (1/80, 1.5%) was lower than reported (2was lower than reported (2--7%).7%).

CTU in 80 pts after CTU in 80 pts after cystectomycystectomy

SadowSadow et al, RSNA 2007et al, RSNA 2007

Early (<1yr)Early (<1yr) Late (>1yr)Late (>1yr)

CTUCTU

I+A/PI+A/P

PostPost--opopConplicationsConplications

UTTUTT

LR, MetsLR, Mets LR, MetsLR, MetsCalculiCalculi

CTU in pts after CTU in pts after cystectomycystectomy

CTU early if CTU early if CxCx suspected; use late?suspected; use late?SadowSadow et al, RSNA 2007et al, RSNA 2007

MRU IndicationsMRU Indications

•• Iodinated CM allergyIodinated CM allergy•• Renal Insufficiency (StaticRenal Insufficiency (Static--fluid MRU)fluid MRU)•• Pregnancy (StaticPregnancy (Static--fluid MRU)fluid MRU)•• Young patients, need for serial Young patients, need for serial f/uf/u

Patient populationsPatient populations……

……CT relatively contraindicatedCT relatively contraindicated

•• No radiationNo radiation•• T1,T2,CE,FS,CSI,DWI T1,T2,CE,FS,CSI,DWI •• Contrast resolutionContrast resolution•• FurosemideFurosemide requiredrequired•• Risk of NSF Risk of NSF •• Long examinationLong examination•• Insensitive for Insensitive for

CaCa2+2+/stones/stones•• UnkUnk. sensitivity for UT. sensitivity for UT•• Inconsistent IQInconsistent IQ

•• RadiationRadiation•• Attenuation, CEAttenuation, CE•• Spatial resolutionSpatial resolution•• FurosemideFurosemide helpful helpful •• Risk of CINRisk of CIN•• Short examinationShort examination•• Sensitive for CaSensitive for Ca2+2+/stones/stones•• Sensitive for UT tumorsSensitive for UT tumors•• Consistent IQConsistent IQ

CT CT UrographyUrography MR MR UrographyUrography

MRU IndicationsMRU Indications

•• If mild, CTU after preIf mild, CTU after pre--medicationmedication•• If severe, MRUIf severe, MRU

What if iodinated CM allergy?What if iodinated CM allergy?

What if pregnant?What if pregnant?•• If pain, If pain, abdabd MRI + evaluate for MRI + evaluate for appyappy•• If If hydronephrosishydronephrosis ?etiology ?etiology -- > static> static--fluid MRUfluid MRU

MRU IndicationsMRU Indications

•• UnenhancedUnenhanced CTCT•• CTU at CTU at ½½ dose CMdose CM•• MRUMRU•• MRU at MRU at ½½ dose CMdose CM•• MRU static MRU static ––fluid only fluid only

What if What if eGFReGFR 3030--60?60?

What if What if eGFReGFR <30?<30?

if 40 if 40 yoyo or youngeror younger

•• UnenhancedUnenhanced CTCT or staticor static--fluid MRUfluid MRU

if over 40 if over 40 yoyo

•• Three phase Three phase –– UP (abdomen and pelvis), NP UP (abdomen and pelvis), NP (kidneys only), EP (abdomen and pelvis), (kidneys only), EP (abdomen and pelvis), supplemented with 10 mg supplemented with 10 mg furosemidefurosemide IVIV

Patients > 40 years oldPatients > 40 years old

•• Split bolus, two phase Split bolus, two phase –– abdomen and abdomen and pelvis, supplemented with 250 cc saline IVpelvis, supplemented with 250 cc saline IV

Patients Patients << 40 years old40 years old

Patients Patients with risk factors for malignancywith risk factors for malignancy

Patients Patients with no risk factors for malignancywith no risk factors for malignancy

•• UnenhancedUnenhanced CT alone if CT alone if << 40 years of age?40 years of age?

Tailor CTU Protocols further?Tailor CTU Protocols further?

Van Van DerDer MolenMolen et al (ESUR) European Radiology 2007et al (ESUR) European Radiology 2007

needed?needed? needed?needed?

CTUCTU

Tailor CTU Protocols further?Tailor CTU Protocols further?

RiskRisk--based approach is on the right track!based approach is on the right track!

•• CTU is the imaging test of CTU is the imaging test of choice for the evaluation of the choice for the evaluation of the upper urinary tract.upper urinary tract.

•• MRU indicated if allergy to MRU indicated if allergy to iodinated CM, pregnancy, renal iodinated CM, pregnancy, renal insufficiency, young patientsinsufficiency, young patients

Role of CTU and MRURole of CTU and MRU