The hazards of lack of co-registration of ictal brain SPECT with MRI: A case report of sinusitis mimicking a brainstem seizure focus.
BACKGROUND: Single photon emission computed tomography (SPECT) following injection of radiotracer during a seizure is known as ictal SPECT. Comparison of an ictal SPECT study to a baseline or interictal study can aid identification of a seizure focus. CASE PRESENTATION: A young woman with encephalitis and refractory seizures underwent brain SPECT during a period of frequent seizure-like episodes, and during a seizure-free period. A focal area of increased radiotracer uptake present only when she was experiencing frequent seizure-like episodes was originally localized to the brainstem, but with later computerized co-registration of SPECT to MRI, was found to lie outside the brain, in the region of the sphenoid sinus. CONCLUSION: Low-resolution SPECT images present difficulties in interpretation, which can be overcome through co-registration to higher-resolution structural images.
Butler
Tracy
T
Functional Neuroimaging Laboratory, Weill Medical College of Cornell University, New York, NY, USA. tab2006@med.cornell.edu.
Hirsch
Lawrence J
LJ
Claassen
Jan
J