Epilepsy
Conditions
Keywords
ictal SPECT
Brief summary
Ictal SPECT with intravenous injection in a cubital vein of a perfusion tracer is an established technique to localize the ictal onset zone during presurgical evaluation of refractory focal epilepsy. When seizures last less than 10 seconds, localizing information is often not obtained. Since it takes around 30 seconds before the tracer reaches the brain after intravenous injection, ictal hyperperfusion most likely has already switched to postictal hypoperfusion. In this study, we plan to inject the perfusion tracer in the aorta proximal to the cerebral arteries, which will allow a true ictal injection in patients with seizures of short duration.
Detailed description
In this study, the investigators will select one patient with refractory focal epilepsy with frequent seizures of short duration, which can not be localized with early ictal SPECT with intravenous injection in a cubital vein. An arterial catheter will be inserted. The right groin will be disinfected using an alcoholic disinfectant and locally anaesthetized. The artery in the groin, the femoral artery, will be punctured. A catheter is inserted in the artery and slided towards the heart. To determine the correct position of the catheter proximal to the cerebral arteries, a contrast agent will be injected, and at the same time radiographs will be taken. The catheter will be attached and taped in the groin. The patient will be monitored with video-EEG recording. During an epileptic seizure, the perfusion tracer 99m-Technetium Ethyl Cysteinate Dimer (99mTc- ECD) dissolved in 30 cc normal saline will be injected with a pressure injector over 2 seconds. After injection, the catheter will be removed and the ictal SPECT scan will be performed. Subtracted ictal SPECT images co-registered with MRI (SISCOM) will be obtained. The investigators plan to do this study in one patient in order to assess whether this procedure is logistically possible and to determine whether subtraction images of ictal SPECT with intra-arterial injection minus interictal SPECT with intravenous injection allows localization of the ictal onset zone.
Interventions
PROCEDUREintra-arterial injection of tracer
intra-arterial ictal injection of perfusion tracer
DRUG99m-Technetium Ethyl Cysteinate Dimer
administration of perfusion tracer 99m Tc-ECD during epileptic seizure
DEVICEintra-arterial catheter
placement of intra-arterial catheter via femoral artery
DEVICEpressure injector
the injection of the perfusion tracer will be delivered with a pressure injector
Sponsors
Universitaire Ziekenhuizen KU Leuven
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
* Refractory unifocal epilepsy * Early ictal SPECT with intravenous injection did not localize the ictal onset zone * Several seizure per day, or clusters of several seizures per day * Seizures are of short duration (i.e. less than 10-15 seconds) * Patient asks for epilepsy surgery
Exclusion criteria
* Renal failure * Allergy to contrast agents * Fever * Anemia * Usage of anticoagulants * Pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Correct localization of the ictal onset zone | 1 year after epilepsy surgery | seizure free outcome will be assessed 1 year after epilepsy surgery and correlated with Subtracted ictal SPECT co-registered with MRI (SISCOM) results |
Countries
Belgium
Outcome results
None listed