# The epileptologist's perspective of focal cortical dysplasia type 3: From concept to management

## TL;DR

This paper discusses the clinical relevance of focal cortical dysplasia type 3 and questions its impact on epilepsy surgery decisions.

## Contribution

The paper challenges the practical significance of FCD type 3 by questioning its preoperative identification and post-surgery relevance.

## Key findings

- FCD type 3 is defined by architectural abnormalities linked to other brain lesions.
- Preoperative identification of dyslamination in FCD type 3 is unreliable.
- The clinical impact of FCD type 3 on epilepsy surgery remains unproven.

## Abstract

The recent International League Against Epilepsy (ILAE) official and updated classification of focal cortical dysplasia (FCD) includes a third type—FCD type 3—characterized by architectural abnormalities (cortical dyslamination) associated with another “principal” lesion: hippocampal sclerosis (HS), developmental tumors, vascular malformations, or gliotic scars. We posit that the clinical relevance of FCD type 3 is not established, as dyslamination cannot be reliably identified preoperatively and (although unproven, because unidentifiable) persistence of cortical tissue with putative dyslamination after resective surgery does not preclude seizure control. Here we discuss these issues from the epileptologist's perspective and stimulate the debate on whether the FCD type 3 construct impacts decision‐making in the epilepsy surgery field—or else is of little practical significance.