Location-based selection of the surgical approach to preserve the hippocampus in lesion-associated temporal lobe epilepsy

Shugo Nishijima; Takehiro Uda; Vich Yindeedej; Toshiyuki Kawashima; Yuta Tanoue; Takeshi Inoue; Ichiro Kuki; Masataka Fukuoka; Megumi Nukui; Shin Okazaki; Noritsugu Kunihiro; Ryoko Umaba; Takeo Goto

doi:10.1016/j.clineuro.2024.108546

Location-based selection of the surgical approach to preserve the hippocampus in lesion-associated temporal lobe epilepsy

Clin Neurol Neurosurg. 2024 Sep 10:246:108546. doi: 10.1016/j.clineuro.2024.108546. Online ahead of print.

Authors

Affiliations

¹ Department of Neurosurgery, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan.
² Department of Neurosurgery, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan; Department of Pediatric Neurosurgery, Osaka City General Hospital, Osaka, Japan. Electronic address: udat@omu.ac.jp.
³ Department of Neurosurgery, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan; Department of Pediatric Neurosurgery, Osaka City General Hospital, Osaka, Japan; Division of Neurosurgery, Department of Surgery, Thammasat University Hospital, Faculty of Medicine, Thammasat University, Pathumthani, Thailand.
⁴ Department of Pediatric Neurology, Osaka City General Hospital, Osaka, Japan.
⁵ Department of Pediatric Neurosurgery, Osaka City General Hospital, Osaka, Japan.

PMID: 39270463
DOI: 10.1016/j.clineuro.2024.108546

Abstract

Background and objectives: Surgical resections for lesions associated with intractable temporal lobe epilepsy (TLE) offers good seizure outcomes.However, the necessity of hippocampectomy in addition to lesionectomy is controversial, especially when the hippocampus is not involved by the lesion. Lesionectomy alone, preserving the hippocampus by an appropriate surgical approach, might offer good seizure outcomes while maintaining neurocognitive function. In the present study, the aims were to examine the surgical strategy for lesions associated with TLE and to present how to select surgical approaches to preserve the hippocampus.

Methods: A total of 22 consecutive lesion-associated TLE patients who underwent lesionectomy alone were retrospectively reviewed. The surgical approach, transsylvian, transorbital, subtemporal, supracerebellar transtentorial, or transcortical approach, was selected based on the location of the lesion. Postoperative seizure outcomes were classified by the Engel classification. Neurocognitive outcomes were assessed before and after surgery if possible. The pathology, the extent of resection, and lesion recurrence were reviewed.

Results: The transsylvian approach was selected in six patients, the transorbital approach in one patient, the subtemporal approach in three patients, the supracerebellar transtentorial approach in five patients, and the transcortical approach in seven patients. Eighteen of 22 (81.8 %) patients achieved Engel's class I or II good seizure outcomes. No patients had neurocognitive deterioration after surgery. Twelve patients had various types of brain tumors, and ten patients had non-tumorous lesions. Gross total resection was achieved in 21 patients. All patients had no recurrence.

Conclusion: For patients with lesion-associated TLE, lesionectomy alone by the appropriate surgical approach offers satisfactory seizure outcomes while preserving hippocampus.

Keywords: Anatomical classification; Cognitive function; Hippocampectomy; Lesionectomy; Seizure outcome; Surgical approach; Temporal lobe epilepsy.