Exploration and Evaluation of Amygdalo-Hippocampectomy According to Prof. Coubes' Technique: An Anatomical, Clinical, and Educational Approach

Title Exploration and Evaluation of Amygdalo-Hippocampectomy Using Pr. Coubes' Technique: An Anatomical, Clinical, and Pedagogical Approach

Introduction The hippocampus, a vital component of the limbic system, plays a key role in memory and emotions. Unfortunately, it is also prone to various pathologies, such as hippocampal sclerosis, a condition characterized by progressive neuronal degeneration and subsequent fibrosis of the medial temporal lobe. Other diseases may occur such as tumours, Dysembryoplastic Neuroepithelial Tumour (DNET) or gliomas.

This condition often leads to severe symptoms, including pharmacoresistant epilepsy and memory disturbances that significantly impair the quality of life.

For patients with pharmacoresistant epilepsy associated with hippocampal sclerosis, surgery has emerged as a first-line therapeutic option. Among the surgical techniques, hippocampectomy and amygdalo-hippocampectomy aim to remove the affected portion of the hippocampus, reducing seizure propagation and improving patient outcomes. However, these procedures are marked by significant variability in their operative techniques, extents of resection, and patient selection criteria.

While the amygdalo-hippocampectomy technique described by Pr. Yasargil in 1985 remains a cornerstone in surgical approaches, other methods such as the trans-sylvian approach (Adada et al., 2008), the trans-gyral approach (Mathon \& Clemenceau, 2016), and emerging endoscopic techniques (H. Westley Phillips, 2023) highlight the diversity and evolution of surgical options.

This study seeks to explore in detail the surgical technique developed by Pr. Coubes, analyzing its anatomical, surgical, and clinical aspects. Additionally, it aims to compare this method with other surgical approaches to understand its benefits and limitations better in managing hippocampal sclerosis.

Objectives Primary Objective

• To describe the complications and the evolution of clinical outcomes in patients treated with Pr. Coubes' amygdalo-hippocampectomy technique.

Secondary Objective - To identify variables associated with favorable seizure control and overall clinical outcomes.

Study Design Type of Study

• Retrospective, single-center study conducted at the CHU de Montpellier.

Population

• 234 patients treated with this technique between 1980 and 2023, representing over three decades of clinical practice.
• Inclusion of both adult and pediatric patients.

Data Collection

• Retrospective extraction of clinical, imaging, and surgical data from patient records via the informatic patients' system.
• Data categories include demographic details, pre- and post-operative imaging (MRI), seizure frequency and type (ILAE criteria), complications, return-to-work rates, and social reintegration metrics.

Methodology Statistical Analysis

• Kaplan-Meier survival curves : Used to evaluate the time to the occurrence of complications or changes in clinical outcomes.
• Cox proportional hazards models : Conducted in both univariate and multivariate settings to identify predictors of post-operative outcomes and complications.

Outcome Measures

• Primary outcome : Seizure control evaluated using ILAE classification.
• Secondary outcomes : Post-operative complications, return-to-work rates, and functional reintegration.

Ethical Considerations

• Data Privacy : All patient data will be pseudonymized according to the French Ethic guidelines, with storage on secure CHU servers for a maximum of two years post-publication.
• Patient Notification : Informational letters will be sent to patients, detailing the study's objectives and their rights to non-opposition.

Expected Contributions

1. Clinical Insights : Comprehensive analysis of over 30 years of surgical practice, offering robust data on the efficacy and safety of Pr. Coubes' technique.
2. Comparative Perspective : Enhanced understanding of how this technique compares to other established and emerging surgical approaches.
3. Pedagogical Value : Detailed anatomical and surgical documentation to guide future training and clinical practice in neurosurgery.

Conclusion This study represents a unique opportunity to document and analyze a long-practiced yet unpublished surgical technique. By consolidating decades of clinical experience and integrating advanced analytical methods, it aims to provide valuable insights for improving the management of hippocampal sclerosis, ultimately advancing patient care and surgical education.