POSITRON EMISSION TOMOGRAPHIC MEASUREMENT OF CEREBRAL BLOOD-FLOW AND TEMPORAL LOBECTOMY

We used positron emission tomography (PET) and bolus injection of (H2O)-O-15 to measure interictal cerebral blood flow (CBF) in 32 patients who had temporal lobectomy for uncontrolled complex partial seizures. Seizure focus localization was confirmed by ictal video-electroencephalographic (video-EEG) telemetry, and patients who had imaging findings suggesting the presence of a tumor were excluded. PET-CBF studies were interpreted using a standard template by raters blinded to EEG and clinical data, and were not used in surgical planning. After surgery, patients were followed for 32 +/- 18 months. Twenty-six patients were seizure free and 6 had persistent seizures. Mean lateral temporal hypoperfusion was 8 +/- 14% in patients who became seizure free and 9 +/- 6% in patients with persistent seizures. Fourteen patients had at least 15%, and 11 at least 20% hypoperfusion, but were not more likely to be seizure free. Three additional patients had 15 to 20% hypoperfusion in the temporal lobe contralateral to their EEG focus. PET measurement of CBF using bolus (H2O)-O-15 should not be used to help select patients for temporal lobectomy.