Surgical strategies after failed hemispheric disconnection surgery: A systematic review and individual-patient data
Daniel Sescu1, Abdel-Rahman Abdel Fattah2, Jose Araya Quezada3
1Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom; Queen Elizabeth Hospital King's Lynn, King's Lynn, United Kingdom; The School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, United Kingdom.
Purpose:
To analyze surgical and seizure outcomes after secondary interventions following failed hemispheric disconnection surgery (hemispherectomy/hemispherotomy).
Methods:
We systematically searched five databases from January 1990 to April 2025. Eligible studies included patients of any age who underwent index hemispheric disconnection surgery (HDS), experienced seizure recurrence, and reported outcomes after secondary interventions: redo hemispheric surgery (RHS), laser interstitial thermal therapy (LITT), or vagus nerve stimulation (VNS). Studies were classified as aggregate or individual-patient data (IPD). Pooled proportions were estimated using random- and common-effects meta-analyses. IPD were analyzed using Kaplan-Meier survival methods and log-rank testing. Risk of bias was assessed using Joanna Briggs Institute tools.
Results:
From 998 records, 25 studies met inclusion criteria, reporting outcomes for RHS (n=151), LITT (n=9), and VNS (n=9). The pooled incidence of reoperation after failed HDS was 18% (95% CI 14-22; I²=0%). Following RHS, Engel I outcome was achieved in 50% (95% CI 33-66; I²=57.4%), and Engel I-II in 69% (95% CI 59-77; I²=0.0%). In IPD analyses, median seizure-free survival after RHS was 4.5 years (95% CI 3.0-6.8), extending to 6.8 years (95% CI 4.5-10.6) for Engel I-II outcomes. Engel I duration was significantly longer after RHS compared with LITT (median 4.5 vs 1.4 years; log-rank p=0.02). Data on VNS were limited and allowed only narrative synthesis.
Conclusions:
To our knowledge, this is the first synthesis focused on seizure outcomes after secondary interventions for failed HDS. Overall, RHS remains the most effective salvage strategy, providing durable seizure control in a substantial proportion of patients. LITT represents a promising minimally invasive alternative with more limited durability, while VNS appears primarily palliative. These findings provide evidence-based benchmarks to guide surgical decision-making and counseling in this challenging population.
