PET of serotonin 1A receptors and cerebral glucose metabolism for temporal lobectomy.
The objective of this study was to compare 5-hydroxytryptamine receptor 1A (5-HT(1A)) PET with cerebral metabolic rate of glucose (CMRglc) PET for temporal lobectomy planning.


METHODS
We estimated 5-HT(1A) receptor binding preoperatively with (18)F-trans-4-fluoro-N-2-[4-(2-methoxyphenyl) piperazin-1-yl]ethyl-N-(2-pyridyl) cyclohexane carboxamide ((18)F-FCWAY) PET and CMRglc measurement with (18)F-FDG in regions drawn on coregistered MRI after partial-volume correction in 41 patients who had anterior temporal lobectomy with at least a 1-y follow-up. Surgery was tailored to individual preresection evaluations and intraoperative electrocorticography. Mean regional asymmetry values and the number of regions with asymmetry exceeding 2 SDs in 16 healthy volunteers were compared between seizure-free and non-seizure-free patients. (18)F-FCWAY but not (18)F-FDG and MRI data were masked for surgical decisions and outcome assessment.


RESULTS
Twenty-six of 41 (63%) patients seizure-free since surgery had significantly different mesial temporal asymmetries, compared with 15 non-seizure-free patients for both (18)F-FCWAY (F(1,39) = 5.87; P = 0.02) and (18)F-FDG PET (F(1,38) = 5.79; P = 0.021). The probability of being seizure-free was explained by both (18)F-FDG and (18)F-FCWAY PET, but not MRI, with a significant additional (18)F-FCWAY effect (chi(2)(2) = 9.8796; P = 0.0072) after the probability of being seizure-free was explained by (18)F-FDG. Although MRI alone was not predictive, any combination of 2 lateralizing imaging studies was highly predictive of seizure freedom.


CONCLUSIONS
Our study provides class III evidence that both 5-HT(1A) receptor PET and CMRglc PET can contribute to temporal lobectomy planning. Additional studies should explore the potential for temporal lobectomy based on interictal electroencephalography and minimally invasive imaging studies.
Clinical Epilepsy Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, USA. theodorw@ninds.nih.gov
William H
WH
Theodore
Ashley R
AR
Martinez
Omar I
OI
Khan
Clarissa J
CJ
Liew
Sungyoung
S
Auh
Irene M
IM
Dustin
John
J
Heiss
Susumu
S
Sato
D000328:Adult; D003510:Cyclohexanes; D004569:Electroencephalography; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D019635:Neurosurgical Procedures; D010879:Piperazines; D049268:Positron-Emission Tomography; D044282:Receptor, Serotonin, 5-HT1A / Q000378:metabolism*; D012189:Retrospective Studies; D058829:Serotonin 5-HT1 Receptor Antagonists; D013702:Temporal Lobe / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000601:surgery
D003510:Cyclohexanes; C493883:N-(2-(4-(2-methoxyphenyl)piperazino))-N-(2-pyridinyl) trans-4-fluorocyclohexanecarboxamide; D010879:Piperazines; D058829:Serotonin 5-HT1 Receptor Antagonists; D019788:Fluorodeoxyglucose F18; D044282:Receptor, Serotonin, 5-HT1A; D005947:Glucose