Evaluation of functional changes in the medial temporal region during intracarotid amobarbital procedure by use of SPECT.
OBJECTIVE
Because the main blood supply to the medial temporal region is through the posterior cerebral artery, the validity of the intracarotid amobarbital procedure (IAP) is still debated. To verify clinical validity of the IAP, we investigated changes in neuronal function in the medial temporal region during IAP.


METHODS
Brain single photon emission computed tomography (SPECT) was performed during IAP (IAP-SPECT) in 22 patients with temporal lobe epilepsy (TLE), and regional cerebral blood flow (rCBF) in the medial and lateral temporal regions of interest (ROIs) was measured quantitatively. To determine the distribution of sodium amobarbital, in another 20 patients with TLE, SPECT images were obtained after intracarotid injection of 99mTc-HMPAO mixed with sodium amobarbital.


RESULTS
Mean rCBF was 89.2% in the medial temporal region and 81.6% in the lateral temporal region: in the former region, it was significantly lower than that shown by the results of interictal SPECT (99.1%; p < 0.001). In a few patients, however, rCBF did not decrease in the medial temporal region. In only 25% of patients, the medial temporal region was visualized in SPECT images obtained after intracarotid injection of 99mTc-HMPAO.


CONCLUSIONS
The results in this study demonstrate that IAP is valid because the medial temporal region is inactivated in spite of infrequent delivery of sodium amobarbital. We assume that intratemporal diaschisis is operating for the inactivation of neuronal function. IAP-SPECT with intratemporal ROIs may be useful for monitoring changes in neuronal function in the medial temporal region during IAP.
Kim
B G
BG
Department of Neurology, College of Medicine, Seoul National University, Korea.
Lee
S K
SK
Nam
H W
HW
Song
H C
HC
Lee
D S
DS
D000293:Adolescent; D000328:Adult; D000654:Amobarbital / Q000008:administration & dosage / Q000494:pharmacology; D002339:Carotid Arteries; D004292:Dominance, Cerebral / Q000187:drug effects / Q000502:physiology; D004833:Epilepsy, Temporal Lobe / Q000503:physiopathology; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000494:pharmacology; D007269:Injections, Intra-Arterial; D008297:Male; D008568:Memory / Q000187:drug effects; D008875:Middle Aged; D012039:Regional Blood Flow; D013060:Speech / Q000187:drug effects / Q000502:physiology; D019690:Technetium Tc 99m Exametazime; D013702:Temporal Lobe / Q000098:blood supply / Q000187:drug effects* / Q000503:physiopathology; D015899:Tomography, Emission-Computed, Single-Photon
D006993:Hypnotics and Sedatives; D019690:Technetium Tc 99m Exametazime; D000654:Amobarbital