Premium
An Evaluation of Intravenous Xenon 133 Clearance Measured by Gamma Counters During lnterictal Cerebral Blood Flow for Epilepsy Surgery
Author(s) -
Dasheiff Richard M.,
Jumao-as Asela
Publication year - 1992
Publication title -
journal of neuroimaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.822
H-Index - 64
eISSN - 1552-6569
pISSN - 1051-2284
DOI - 10.1111/jon19922271
Subject(s) - ictal , medicine , cerebral blood flow , epilepsy , nuclear medicine , anesthesia , electroencephalography , blood flow , radiology , psychiatry
Fifty‐four consecutive adult patients who enrolled in an epilepsy surgery program were prospectively studied to evaluate the utility of cerebral blood flow (CBF) for identifying the site of the epileptic focus. Tracer was injected intravenously during the interictal state, and CBF was estimated by the clearance of xenon 133 ( 133 Xe) using a two‐compartment analysis. Extracranial monitoring of gamma radiation was performed by 32 collimated detectors placed over the head. Every patient subsequently had depth electrodes implanted into mesial temporal and mesial frontal regions bilaterally. Two patients also had occipital electrodes implanted, and 1 patient also had parietal electrodes implanted. Seizures were recorded from all patients using these depth electrodes and a closed‐circuit television monitor. A total of 79 ictal foci were identified. CBF 133 Xe as determined by clearance was concordant in 20 foci (true‐positive rate of 25%), with 59 false‐negative (75%) and 25 false‐positive results. The overall sensitivity of this CBF study (compared to ictal depth electroencephalography) was 0.25, and the specificity was 0.82. It was concluded that present 133 Xe CBF techniques are inadequate to identify an epileptic focus during the interictal state in adult patients.