5-ALA fluorescence to guide surgery in drug-resistant epilepsy from focal cortical dysplasia

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for people aged 3 years and older with drug-resistant epilepsy caused by a type II focal cortical dysplasia (FCD) seen on MRI, who are having their first FCD surgery.

Age

3 years and older

Sex

All sexes can join.

Disease stage

Drug-resistant epilepsy related to a type II focal cortical dysplasia (FCD) visible on MRI. Surgery has been agreed by the epilepsy multi-disciplinary team.

Earlier treatment

This must be the first FCD surgery.

Main reasons for not taking part

• Weight over 75kg (165 lb (75 kg))
• Needing general anaesthesia for MRI
• Cannot have an MRI (for example obesity, claustrophobia, metal object)
• Allergy to the active substance or to porphyrins, or acute or chronic porphyria
• Pregnancy or breastfeeding, or not willing to follow the contraception rules

The registry criteria, word for word

What the trial wants to find out

Epilepsy is one of the most common neurological disorders, with one of the highest morbidity rates of all diseases. Despite the development of new anticonvulsant drugs, around a third of patients suffer from drug-resistant epilepsy (RPE). The onset of RPE can be lengthy, prolonging the period during which affected patients live with seizures that have a negative impact on their quality of life. Epilepsy surgery can be a curative treatment, and can enable anticonvulsant medication to be discontinued, optimizing quality of life and cognitive development. In addition, as it has been shown that the prolonged duration of epilepsy prior to surgery has an impact on the occurrence of postoperative seizures, early surgery is increasingly being considered. Focal cortical dysplasia (FCD) is the leading cause of focal lesional epilepsy and is generally drug-resistant. Good postoperative seizure results after surgical resection are strongly linked to complete resection of the dysplastic tissue. Consequently, accurate localization and precise delineation of FCD lesions are crucial during surgery. Currently, the extent of surgical resection is based primarily on preoperative examination, as the macroscopic appearance of dysplastic tissue does not differ from normal cortex. The various intraoperative techniques available to improve the quality of excision (neuronavigation, ultrasound, intraoperative MRI and intraoperative guidance by fluorescence microscopy) all have their limitations. In this context, new intraoperative tools are needed to help the neurosurgeon delineate lesions during surgery. Intraoperative fluorescence spectroscopy is used for surgical guidance of gliomas and other brain pathologies, and has demonstrated its ability to characterize pathological tissues. DCFs exhibit metabolic differences that can also be detected by 5-amino-levulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence intraoperatively. Indeed, in some patients who underwent surgery after a diagnosis of glioma, fluorescence was observed even though histological analysis classified the excised tissue as DCF. What's more, glioma and DCF share a common feature: the mitochondria of affected cells are deficient in complex IV. Cytochrome c oxidase (CCO) is largely involved in mitochondrial complex IV, and NAD is a central metabolite involved in redox reactions within cells. Both metabolites (CCO and NAD) can be visualized intraoperatively by optical and fluorescence spectroscopy.

The group in the trial

• 5-ALA (Gliolan)Treatment being tested

  Children and adults with drug resistant epilepsy, related to a probable FCD and with surgical indication validated by the epileptic multi-disciplinary staff meeting will receive the study treatment (5-ALA) orally at a dose of 20mg/kg