Ictal SPECT and interictal PET in the localization of occipital lobe epilepsy.
OBJECTIVE
To compare the localizing value of ictal single photon emission computed tomography (SPECT) and interictal fluorodeoxyglucose-positron emission tomography (FDG-PET) in refractory occipital lobe epilepsy.


METHODS
Six patients who underwent surgery for refractory epilepsy associated with pathology in the occipital lobe were retrospectively selected from records of the Austin & Repatriation Centre Comprehensive Epilepsy Programme. Interictal SPECT and PET and ictal SPECT were obtained by standard methods. All studies were read by a nuclear medicine expert blinded to clinical data except the diagnosis of epilepsy.


RESULTS
Ictal SPECT showed unilateral occipital hyperperfusion in five of six cases often accompanied by temporal lobe hyperperfusion. These patterns were seen in cases with or without magnetic resonance imaging (MRI) abnormality. Interictal SPECT was not localizing in any case, in contrast to PET, which showed occipital hypometabolism in three of five studies.


CONCLUSIONS
Ictal SPECT can provide novel localizing data in MRI-negative occipital lobe epilepsy. Interictal PET can provide useful localizing information, but its role in providing novel information was not demonstrated. Interictal SPECT is useful only as a baseline to aid in interpretation of ictal studies.
Sturm
J W
JW
Departments of Neurology, Austin and Repatriation Medical Centre, and Medicine, University of Melbourne, Heidelberg, Victoria, Australia.
Newton
M R
MR
Chinvarun
Y
Y
Berlangieri
S U
SU
Berkovic
S F
SF
D000328:Adult; D017668:Age of Onset; D004828:Epilepsies, Partial / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009778:Occipital Lobe / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000503:physiopathology; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000503:physiopathology; D014055:Tomography, Emission-Computed; D015899:Tomography, Emission-Computed, Single-Photon
D019788:Fluorodeoxyglucose F18