CT perfusion with angiography as a substitute for both conventional digital subtraction angiography and acetazolamide-challenged SPECT in the follow-up of postbypass patients.
BACKGROUND
We evaluated the clinical usefulness of CT perfusion (CTP) with angiography (CTA) as an alternative to digital subtraction angiography (DSA) and acetazolamide (ACZ)-challenged single-photon emission computed tomography (SPECT) in the follow-up evaluation of hemodynamic changes and bypass patency after bypass surgery in chronic cerebral ischemic diseases.


METHODS
Thirty-five patients who underwent superficial temporal artery/middle cerebral artery bypass surgery for chronic cerebral ischemic diseases were retrospectively enrolled. We assessed the relationship between CTP parameters [cerebral blood volume, cerebral blood flow (CBF), mean transit time (MTT), affected-to-unaffected hemisphere (ATU) ratio of perfusion parameters and MTT differences between hemispheres] and SPECT parameters (regional CBF and cerebrovascular reserve) and compared the preoperative CTP parameters with the postoperative ones. For the bypass patency, we compared CTA with DSA.


RESULTS
MTT showed the best correlation with CVR of SPECT (r = -0.343; p < 0.001). ATU ratio (r = -0.547; p < 0.001) and ATU differences (r = -0.592; p < 0.001) of MTT correlated well with the ATU ratio of rCBF on ACZ-challenged SPECT. Significant improvement of perfusion parameters could be demonstrated in the affected vascular territory with postoperative CTP. The CTA findings were consistent with those of DSA in 96% of the cases. The examination-related complication rate was 0, 2.8 and 8.6% for CT studies, DSA and SPECT, respectively.


CONCLUSIONS
CTP performed simultaneously with CTA seems to be a safe and efficient substitute for DSA and ACZ-challenged SPECT in the follow-up evaluation after bypass surgery in patients with chronic cerebral ischemic diseases.
Department of Neurosurgery, Jeju National University College of Medicine, Jeju, South Korea.
Jung Cheol
JC
Park
Jeong Eun
JE
Kim
Hyun-Seung
HS
Kang
Chul-Ho
CH
Sohn
Dong Soo
DS
Lee
Chang Wan
CW
Oh
Moon Hee
MH
Han
D000086:Acetazolamide; D000293:Adolescent; D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction / Q000009:adverse effects; D001783:Blood Flow Velocity; D001810:Blood Volume; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D002548:Cerebral Revascularization; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D055420:Perfusion Imaging / Q000009:adverse effects / Q000379:methods*; D011237:Predictive Value of Tests; D056910:Republic of Korea; D012189:Retrospective Studies; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000009:adverse effects; D014057:Tomography, X-Ray Computed / Q000009:adverse effects; D016896:Treatment Outcome; D014654:Vascular Patency; D055815:Young Adult
D000086:Acetazolamide