Ictal SPECT in Nonconvulsive Status Epilepticus
Abstract number :
1.220
Submission category :
Year :
2001
Submission ID :
3108
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
J.L. Beattie, M.D., Neurology, University of Michigan, Ann Arbor, MI; E.A. Passaro, M.D., Neurology, University of Michigan, Ann Arbor, MI; E. Kutluay, M.D., Neurology, University of Michigan, Ann Arbor, MI; C.J. Milling, M.D., Neurology, University of Mi
RATIONALE: Non-convulsive status epilepticus (NCSE), which can be generalized or partial in onset, is sometimes difficult to diagnose since it can present with subtle motor or cognitive changes and equivocal EEG findings. We report the findings of ictal single photon emission computed tomography (SPECT) in three patients with partial NCSE.
METHODS: A review of the database at the University of Michigan Medical Center identified three patients who underwent ictal SPECT during NCSE. Ictal SPECT injections were done with 30 mCi [Tc99] ECD at the time of the electrographic seizures. Two patients also had inter-ictal injections following resolution of NCSE for subtraction SPECT imaging.
RESULTS: Case 1: 17-year-old female with a history of a left fronto-polar abscess resection presented with disinhibition, irritability and euphoria with preserved awareness. Ictal EEG: Left semi-rhythmic frontal sharp activity localized to the area of the breach defect. Ictal SPECT: Left fronto-polar hyperperfusion. Outcome: surgical resection of encephalomalacia. Case 2: 34-year-old female with spells characterized by staring, unresponsiveness, inability to speak, crying and waxy flexibility lasting 2-to-6 hours. Ictal EEG: Diffuse high amplitude delta range slowing intermixed with generalized spikes, polyspikes that waxed and waned with a left centro-parietal maximum. Ictal SPECT: Left centro-parietal hyperperfusion. Outcome: Completing presurgical evaluation. Case 3: 42-year-old female with history of strokes and seizures with a recent onset mental status change and aphasia. Ictal EEG: Periodic spikes and sharp waves up to 6 Hz in the left posterior temporal and occipital region. Ictal SPECT: hyperperfusion in the left perisylvian region extending into the left posterior cingulate gyrus. Outcome: Resolution of status following treatment. In all cases ictal SPECT images showed hyperperfusion that correlated with the ictal EEG.
CONCLUSIONS: Our results show that ictal SPECT imaging is a useful diagnostic tool in the confirmation of NCSE with subtle features. In addition, the results of the ictal SPECT in two of those patients were instrumental in localizing the epileptogenic zone for epilepsy surgery.