{"id":"1a145f66-36c6-4387-8001-635755ee3291","slug":"early-t2-weighted-magnetic-resonance-imaging-changes-after-microsurgical-clipping-of-unruptured-aneurysms-biomarkers-of-corridor-related-tissue-impact","title":"Early T2-weighted magnetic resonance imaging changes after microsurgical clipping of unruptured aneurysms: Biomarkers of corridor-related tissue impact","authors":["Shunsuke Kawamoto","Go Ikeda","Shunsuke Fukaya","Kanae Okunuki","Hiroyoshi Akutsu"],"abstract":"Background: Diffusion-weighted imaging (DWI) detects ischemic injury after microsurgical clipping of unruptured intracranial aneurysms (UIAs), yet non-ischemic parenchymal effects remain poorly characterized. This study evaluated early postoperative T2-weighted imaging (T2WI) abnormalities to characterize corridor-related tissue impact and identify anatomical determinants of non-ischemic parenchymal changes. Methods: This retrospective study analyzed 797 anterior circulation UIA clipping procedures performed by a single surgeon under uniform protocol. Early postoperative magnetic resonance imaging (day 4–5) and 12-month follow-up were obtained. T2WI hyperintensities without restricted diffusion were classified as non-ischemic parenchymal changes. Stratified analyses isolated the effects of aneurysm depth within trans-sylvian (TS) approaches and rectal gyrus separation within interhemispheric (IH) approaches. Multivariate regression identified independent predictors. Results: Non-ischemic T2WI changes occurred in 20.1% (160/797) of procedures. IH approaches showed significantly higher incidence (50.7%) than TS approaches (13.8%, P P P P P = 0.015). At 12-month follow-up, 97.2% of lesions resolved or decreased. DWI-detected ischemia occurred in 7.0% of procedures. No permanent neurological deficits occurred. Conclusion: Early postoperative T2WI abnormalities represent a distinct imaging signature of corridor-related tissue impact, strongly associated with approach depth and anatomy. Their reversibility indicates transient mechanical stress rather than permanent injury. T2WI serves as an objective biomarker complementing DWI-based assessment and may inform surgical quality monitoring and patient counseling.","thumbnailUrl":"https://sni-digital-videos.s3.amazonaws.com/articles/1a145f66-36c6-4387-8001-635755ee3291/featured/hero-1781557943636.png","publishDate":"2026-02-06T00:00:00.000Z","doi":"10.25259/SNI_1309_2025","categories":["Neurovascular","Original Article"],"fullTextUrl":"https://surgicalneurologyint.com/wp-content/uploads/2026/02/14285/SNI-17-71.pdf"}