Feasibility of SPECT for studies of brain perfusion during cardiopulmonary bypass.
Single-photon emission computed tomography (SPECT) and transcranial Doppler (TCD) ultrasonography were used to assess brain perfusion during cardiopulmonary bypass. Intravenous injections of technetium 99 m-hexamethylpropyleneamineoxime (99mTc-HMPAO) were administered before surgery and intraoperatively after the first 2 minutes in the first patient and at the end (42 minutes) of cardiopulmonary bypass in the second patient. The total middle cerebral artery territory counts were calculated using the region-of-interest method and compared to cerebellar regional counts. 99mTc-HMPAO uptake on SPECT scans was increased at the beginning and at the end of cardiopulmonary bypass, compared to baseline preoperative values (11-17%) in the presence of multiple microembolic signals on TCD (n1 = 35 and n2 = 42 for unilateral middle cerebral artery monitoring). These results indicate the feasibility of using HMPAO-SPECT to study brain perfusion changes during cardiac surgery. A combination of SPECT and TCD ultrasonography may be used to study the impact of microembolism during cardiac surgery with cardiopulmonary bypass.
Department of Anesthesiology, Buffalo General Hospital, State University of New York, USA.
S
S
Marochnik
A V
AV
Alexandrov
D
D
Anthone
C
C
Lewin
C B
CB
Caldwell
P M
PM
Pullicino
D001921:Brain / Q000000981:diagnostic imaging*; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D002531:Cerebellum / Q000098:blood supply; D002536:Cerebral Arteries / Q000000981:diagnostic imaging / Q000502:physiology; D002560:Cerebrovascular Circulation; D004453:Echoencephalography; D005240:Feasibility Studies; D006801:Humans; D002542:Intracranial Embolism and Thrombosis / Q000000981:diagnostic imaging; D016343:Monitoring, Intraoperative; D015609:Organotechnetium Compounds; D010091:Oximes; D010865:Pilot Projects; D019690:Technetium Tc 99m Exametazime; D015899:Tomography, Emission-Computed, Single-Photon; D017585:Ultrasonography, Doppler, Transcranial
D015609:Organotechnetium Compounds; D010091:Oximes; D019690:Technetium Tc 99m Exametazime