Epilepsy Surgery in Kazakhstan: Outcomes and the Role of Advanced Imaging.
Dina Kalinina, Nazira Bekenova, Alimzhan Muxunov, Zhassulan Utebekov, Gaziz Kyrgyzbay, Darkhan Kimadiev, Guldana Zhumabaeva, Antonio Sarria-Santamera
Abstract
Open AccessBackground and Objectives: Evidence on epilepsy surgery from Central Asia is limited, reflecting the real-world challenges of developing this service in low- and middle-income settings. We evaluated one-year seizure outcomes after resective surgery for drug-resistant focal epilepsy at a single center in Kazakhstan, and we assessed whether the use of advanced presurgical imaging was associated with seizure freedom. Materials and Methods: A retrospective cohort study was conducted, including consecutive adults who underwent curative-intent resective epilepsy surgery from 2017 to 2023. Outcomes at 12 months or more post-surgery were classified using the Engel criteria. Logistic regression was used to examine associations between the advanced presurgical diagnostic tool and achieving an Engel class I outcome. Crude and adjusted risk ratios (RRs) for not achieving Engel I were estimated using modified Poisson regression with robust SEs. Results: Among 112 patients (median age 31 years; median epilepsy duration 19 years), 76% underwent temporal lobe procedures and 71% had lobectomies. At one year, 74 patients were seizure-free (Engel II: 15.2%, III: 11.6%, IV: 7.1%). Year-to-year Engel I rates varied without a significant linear trend from 2018 to 2023. In bivariable analyses, MRI-defined atrophy (RR, 3.14) and mixed lesions (RR, 2.62) were associated with a higher risk of not achieving Engel I, whereas longer epilepsy duration was linked to a lower risk (RR, 0.97 per year). In adjusted models, predictors of not achieving Engel I included generalized tonic-clonic seizures (aRR, 1.96), atrophy (aRR, 2.98), mixed lesions (aRR, 2.45), and undergoing any advanced diagnostic test (aRR, 3.38). Longer epilepsy durations remained protective (aRR 0.95 per year). In modality-specific logistic models, fMRI use was associated with higher odds of Engel I (aOR 3.39), and MR spectroscopy was associated with lower odds (aOR 0.33). Conclusions: In this Central Asian single-center cohort, about two-thirds of adults achieved complete seizure freedom one year after resective surgery-comparable to international benchmarks. Advanced imaging modalities showed divergent associations with outcomes, likely reflecting confounding by indication. These findings support the feasibility of effective epilepsy surgery in a low-resource context and the value of targeted use of advanced imaging.