Acta Neurochirurgica最新文献

{"title":"How I do it: > 8 Carmustine wafer implantation during supra-marginal resection of a glioblastoma, IDH-wildtype","authors":"Alexandre Roux,&nbsp;Angela Elia,&nbsp;Marc Zanello,&nbsp;Johan Pallud","doi":"10.1007/s00701-025-06675-5","DOIUrl":"10.1007/s00701-025-06675-5","url":null,"abstract":"<div><h3>Background</h3><p>The maximal safe resection of glioblastoma, <i>IDH</i>-wildtype often creates a large resection cavity that can accommodate more than eight Carmustine implants.</p><h3>Method</h3><p>We detail the implantation technique of 13 Carmustine wafers within the surgical bed after a right hippocampal formation-sparing anterior temporal lobectomy allowing for the supra-marginal resection of a glioblastoma <i>IDH</i>-wildtype in an adult patient.</p><h3>Conclusion</h3><p>Carmustine wafer implantation is a safe and efficient technique following surgical resection of a glioblastoma, <i>IDH</i>-wildtype. Sequential technical steps are required to improve the safety and the efficacy of Carmustine wafer implantation. More than eight Carmustine wafers could be implanted in large surgical cavities with survival benefits for the patients.</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06675-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145079050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal woven endobridge (WEB) device-aneurysm volume: using automated volumetric software to predict aneurysmal occlusion status after WEB treatment","authors":"Yosuke Kawamura,&nbsp;Tomoji Takigawa,&nbsp;Masaya Nagaishi,&nbsp;Akio Hyodo,&nbsp;Kensuke Suzuki","doi":"10.1007/s00701-025-06558-9","DOIUrl":"10.1007/s00701-025-06558-9","url":null,"abstract":"<div><h3>Background</h3><p>Optimal Woven EndoBridge (WEB) sizing is crucial for successful implantation. We used three-dimensional (3D) software, Siemens Aneurysm Analysis v. VD30B, to determine the potential of WEB device-aneurysm volume (DAV) ratios in predicting post-treatment occlusion status.</p><h3>Methods</h3><p>We retrospectively reviewed 35 unruptured intracranial wide-neck bifurcation aneurysms treated using the WEB. The study evaluated the association between the DAV ratio and aneurysm obliteration during follow-up. The primary aim of the study was to determine the optimal DAV ratio for predicting occlusion status following WEB treatment.</p><h3>Results</h3><p>The success rate of treating all unruptured aneurysms with the WEB was 100%. The median duration to final follow-up was 365 ± 184.0 days with all 35 patients having a mean modified Rankin Scale score of 0. One (2.9%) patient experienced a transient ischemic attack with hemiparesis perioperatively. A follow-up angiography revealed complete occlusion (WEB Occlusion Scale [WOS] A and B) in 25 (71.4%) of 35 patients and WOS C and D in 10 (28.6%) of 35. The median DAV ratio significantly differed between the groups. The median DAV ratios were 0.97 in the complete occlusion group and 0.84 in the WOS C and D group, respectively (<i>p</i> = 0.002). A receiver operating characteristic curve produced an area under the curve of 0.76 (confidence interval: 0.56–0.96). The optimal DAV ratio cut-off and the highest Youden index for complete occlusion was 0.90.</p><h3>Conclusion</h3><p>Calculating DAV ratios using 3D software may help improve the rate of complete occlusion following WEB treatment.</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06558-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145037371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predictors of shunt response in iNPH: differentiating responders, early and late non-responders, and the role of valve adjustments","authors":"Santhosh G. Thavarajasingam,&nbsp;Mahmoud El-Khatib,&nbsp;Stefania Roxana Kalb,&nbsp;Ahmed Salih,&nbsp;Daniele S. C. Ramsay,&nbsp;Ahkash Thavarajasingam,&nbsp;Dragan Jankovic,&nbsp;Malte Ottenhausen,&nbsp;Darius Kalasauskas,&nbsp;Andreas Kramer,&nbsp;Angelika Gutenberg,&nbsp;Florian Ringel","doi":"10.1007/s00701-025-06663-9","DOIUrl":"10.1007/s00701-025-06663-9","url":null,"abstract":"<div><h3>Introduction</h3><p>Idiopathic normal pressure hydrocephalus (iNPH) is diagnosed based on a positive shunt response. However, up to 40% of patients who undergo ventriculoperitoneal (VP) shunting fail to exhibit sustained improvement. The management of iNPH remains challenging, particularly for non-responders who deteriorate despite surgery. We aimed to determine what features differentiate between long term versus short term responders and do valve adjustments affect their outcome?</p><h3>Material and methods</h3><p>We included patients that underwent ventriculoperitoneal shunt surgery for iNPH between December 2006 and December 2016. Patients were stratified as early (&lt; 6 months) and late (&gt; 6 months) non-responders, and responders. Descriptive statistics, time series plotting, chi-squared tests, and ANOVA analyses were used.</p><h3>Results</h3><p>Our cohort of 65 iNPH patients exhibited a mean follow-up of 3.75 years and consisted of 53.8% early non-responders, 15.4% late non-responders, and 30.8% responders. Comorbidities were distributed across all groups but did not significantly differentiate between response categories. A considerable subset experienced symptom deterioration after the six months mark. Shunt valve adjustments were more frequent in non-responders but did not prevent continued deterioration. In late non-responders, valve adjustments merely slowed symptom progression, without halting deterioration.</p><h3>Conclusion</h3><p>Our study underscores that valve pressure adjustments in early non-responders, who likely never benefit from shunt surgery, are not effective, and highlights the emergence of a late non-responder phenotype, where symptom deterioration becomes evident 6 months post-shunting. Our findings outline the need to explore alternative treatment strategies for managing symptoms in iNPH non-responders, as well as prolonged follow-up regimens to monitor late non-responders.\u0000</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06663-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145037372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative analysis of surgical and endovascular aneurysm repair in subarachnoid hemorrhage: a single-center study with 1,171 patients","authors":"Per Kristian Eide,&nbsp;Wilhelm Sorteberg,&nbsp;Are H. Pripp,&nbsp;Pål A. Rønning,&nbsp;Angelika G. Sorteberg","doi":"10.1007/s00701-025-06670-w","DOIUrl":"10.1007/s00701-025-06670-w","url":null,"abstract":"<div><h3>Background</h3><p>To compare surgical and endovascular therapy (EVT) approaches to aneurysm repair in all aneurysmal subarachnoid hemorrhage (aSAH) patients treated within our institution over a 12-year period from 2011 to 2022.</p><h3>Methods</h3><p>The study comprised a retrospective analysis of prospectively collected data extracted from a hospital quality registry that we established in 2011, containing comprehensive information about all patients treated for aSAH. We included SAH patients within the institution's catchment area who underwent surgical or endovascular aneurysm repair. Exclusion criteria involved patients from external regions, those treated at other institutions, no aneurysm repair performed, or instances undergoing a combination of surgery and EVT. Pretreatment data encompassed the clinical condition at admission, comorbidity, radiological details, aneurysm characteristics, and duration between the bleed and aneurysm repair. Mortality was primary outcome measure; secondary outcome included modified Rankin Score after approximately six months.</p><h3>Results</h3><p>The study encompassed 1,171 patients (65% women and 35% men) undergoing aneurysm repair from 2011 to 2022. Admission data revealed 31.1% in Hunt-Hess grade 4–5. Surgical repair was performed in 573 (48.9%) patients, and EVT in 598 (51.1%) patients. Pretreatment information was comparable for both groups. Kaplan–Meier survival curves demonstrated lower mortality in the surgical than the EVT group (<i>P</i> = 0.023; Log-rank test) over the 12-year period. The 1-year, 5-year, and 10-year mortality rates were 12.4%, 19.5%, and 27.7% for the surgery group, and 18.7%, 25.2%, and 31.7% for the EVT group, respectively. Modified Rankin Score was worse for EVT. There was lower mortality in surgical than EVT groups in patients treated for anterior communicating artery (ACOM, <i>n</i> = 420) and posterior communicating artery (PCOM, <i>n</i> = 177) aneurysms. Shorter time to aneurysm repair and more extensive cerebrospinal fluid (CSF) drainage characterized the surgery group.</p><h3>Conclusions</h3><p>Mortality was lower in surgical patients. Plausible explanations are the maintenance of surgical skills and prompt reduction of intracranial pressure.\u0000</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06670-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145037373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resection of thoracic meningioma with hoth augmented reality system: technical note and operative video","authors":"Naser Ibrahim MD,&nbsp;Shuhei Shiino BA,&nbsp;Kenneth Nguyen BS,&nbsp;Stephen Shapiro MD,&nbsp;Andrew Janssen MD,&nbsp;Aaron Dumont MD","doi":"10.1007/s00701-025-06659-5","DOIUrl":"10.1007/s00701-025-06659-5","url":null,"abstract":"<div><h3>Background</h3><p>Augmented Reality (AR) is an emerging technology in the field of neurosurgery. It allows surgeons to view three-dimensional (3D) patient anatomy overlaid onto the surgical field in real time. In this technical report, we describe the preoperative and intraoperative use of the Hoth AR system for resection of a thoracic meningioma.</p><h3>Methods</h3><p>Prior to surgery, the 3D model of the patient’s tumor and surrounding anatomy is rendered from the patient’s preoperative imaging, and it is uploaded into the AR headset. Once the patient is positioned in the operating room, registration is performed by tracing reference points on the skin while wearing the headset. The surgeon wears the headset while operating, and they can toggle on–off and transparency of each component of the model using voice commands to best visualize the 3D rendering overlaid on the patient’s anatomy.</p><h3>Results</h3><p>We provide a video case demonstrating the use of the Hoth AR system for resection of a thoracic meningioma. The system was able to register the model to the patient accurately in under 30 s. It was used to accurately plan the incision preoperatively, determine levels for laminectomy intraoperatively, and for precise localization of the tumor prior to opening the dura.</p><h3>Conclusion</h3><p>This case describes the clinical integration of a novel AR system for preoperative localization and intraoperative visualization during a resection of a thoracic meningioma. As AR systems continue to evolve and become more accessible, they are poised to become a standard tool in the surgical arsenal.</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06659-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145037483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultrasonographic assessment of bypass capacity after revascularization surgery in moyamoya disease: a systematic review and single-arm meta-analysis","authors":"Natalia Anna Koc,&nbsp;Maurycy Rakowski MD,&nbsp;Samuel D. Pettersson,&nbsp;Paulina Skrzypkowska MD,&nbsp;Tomasz Szmuda MD, PhD,&nbsp;Piotr Zieliński MD, PhD","doi":"10.1007/s00701-025-06658-6","DOIUrl":"10.1007/s00701-025-06658-6","url":null,"abstract":"<div><h3>Purpose</h3><p>Moyamoya disease (MMD) is a chronic cerebrovascular disorder characterized by progressive arterial stenosis and fragile collateral formation, elevating stroke risk. Revascularization is the standard treatment, yet up to 27% of patients experience ischemic events within a year due to bypass insufficiency. While digital subtraction angiography (DSA) remains the gold standard for assessing bypass function, it is invasive and time-consuming. This study evaluates ultrasonography (US) as a noninvasive, cost-effective tool to assess bypass capacity post-revascularization in MMD.</p><h3>Methods</h3><p>A systematic search was conducted following PRISMA guidelines. PubMed, Web of Science, and Scopus were searched for studies reporting US parameters with control imaging confirming bypass capacity. Study quality was assessed using the Newcastle–Ottawa Scale. Mean difference (MD) values were calculated using random-effects models. High bypass capacity was defined as good patency or favorable collateral development.</p><h3>Results</h3><p>Eight cohort studies comprising 264 MMD patients and 301 operated hemispheres were included, with 180 demonstrating high bypass capacity. Within two weeks post-surgery, increased superficial temporal artery (STA) peak systolic velocity (PSV, MD = 28.26, <i>p</i> &lt; 0.0001), mean flow velocity (MFV, MD = 22.97, <i>p</i> = 0.03), end-diastolic velocity (EDV, MD = 33.45, <i>p</i> &lt; 0.0001), and decreased resistance index (RI, MD = –0.09, <i>p</i> = 0.006) were predictive. External carotid artery (ECA) EDV (MD = 13.92, <i>p</i> = 0.04) was also significant. At 3–6 months, elevated EDV in both STA (MD = 8.13, <i>p</i> = 0.006) and ECA (MD = 8.71, <i>p</i> = 0.0002) remained predictive. In the indirect subgroup, lower anterior cerebral artery (ACA) MFV within 0–3 months predicted favorable outcomes (MD = –64.98, <i>p</i> = 0.001).</p><h3>Conclusions</h3><p>Changes in STA and ECA US parameters measured following revascularization surgery predict high bypass capacity. Decreased ACA MFV suggests effective revascularization after indirect surgery. Ultrasound modality offers a valuable, noninvasive tool for postoperative assessment in MMD.</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06658-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145021499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative performance of neurosurgery-specific, peer-reviewed versus general AI chatbots in bilingual board examinations: evaluating accuracy, consistency, and error minimization strategies","authors":"Mahmut Çamlar,&nbsp;Umut Tan Sevgi,&nbsp;Gökberk Erol,&nbsp;Furkan Karakaş,&nbsp;Yücel Doğruel,&nbsp;Abuzer Güngör","doi":"10.1007/s00701-025-06628-y","DOIUrl":"10.1007/s00701-025-06628-y","url":null,"abstract":"<div><h3>Background</h3><p>Recent studies suggest that large language models (LLMs) such as ChatGPT are useful tools for medical students or residents when preparing for examinations. These studies, especially those conducted with multiple-choice questions, emphasize that the level of knowledge and response consistency of the LLMs are generally acceptable; however, further optimization is needed in areas such as case discussion, interpretation, and language proficiency. Therefore, this study aimed to evaluate the performance of six distinct LLMs for Turkish and English neurosurgery multiple-choice questions and assess their accuracy and consistency in a specialized medical context.</p><h3>Methods</h3><p>A total of 599 multiple-choice questions drawn from Turkish Board examinations and an English neurosurgery question bank were presented to six LLMs (ChatGPT-o1pro, ChatGPT-4, AtlasGPT, Gemini, Copilot, and ChatGPT-3.5). Correctness rates were compared using the proportion z-test, and inter-model consistency was examined using Cohen’s kappa.</p><h3>Results</h3><p>ChatGPT-o1pro, ChatGPT-4, and AtlasGPT demonstrated relatively high accuracy for Single Best Answer–Recall of Knowledge (SBA-R), Single Best Answer–Interpretative Application of Knowledge (SBA-I), and True/False question types; however, performance notably decreased for questions with images, with some models leaving many unanswered items.</p><h3>Conclusion</h3><p>Our findings suggest that GPT-4-based models and AtlasGPT can handle specialized neurosurgery questions at a near-expert level for SBA-R, SBA-I, and True/False formats. Nevertheless, all models exhibit notable limitations in questions with images, indicating that these tools remain supplementary rather than definitive solutions for neurosurgical training and decision-making.</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06628-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145011463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cerebral vasospasm following clipping of unruptured middle cerebral artery aneurysms: a case report and literature review","authors":"Yusuke Otsu,&nbsp;Kohei Miyagi,&nbsp;Chihiro Takashima,&nbsp;Jin Kikuchi,&nbsp;Sosho Kajiwara,&nbsp;Tetsuya Negoto,&nbsp;Kimihiko Orito,&nbsp;Kiyohiko Sakata,&nbsp;Masaru Hirohata,&nbsp;Motohiro Morioka","doi":"10.1007/s00701-025-06596-3","DOIUrl":"10.1007/s00701-025-06596-3","url":null,"abstract":"<div><p>We report a 64-year-old woman who developed symptomatic vasospasm on postoperative day 7 after clipping of an unruptured right middle cerebral artery (MCA) aneurysm. Imaging revealed right MCA vasospasm, which resolved with oral antiplatelets and intravenous vasodilators. She was discharged without neurological deficits. Although a few reports describe vasospasm after clipping unruptured aneurysms, this is the first to detail the clinical course, radiological findings, and treatment response. Potential risk factors include female sex, age 40–60, smoking, trigeminal neuralgia, and complex aneurysms. This case underscores the need to consider vasospasm even without subarachnoid hemorrhage for timely intervention.</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06596-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145011720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Awake surgery with direct electrical stimulation mapping and real-time cognitive monitoring for functionally guided tumor resection: how we do it","authors":"Fabien Almairac,&nbsp;Hugues Duffau","doi":"10.1007/s00701-025-06656-8","DOIUrl":"10.1007/s00701-025-06656-8","url":null,"abstract":"<div><h3>Background</h3><p>Awake surgery is the reference for diffuse low-grade glioma resection, allowing maximal tumor removal while preserving neurocognitive functions. It is also applicable to other brain tumors. However, key technical elements must be followed to ensure optimal conditions for intraoperative cognitive testing and reliable functional mapping.</p><h3>Method</h3><p>We describe the asleep–awake–asleep technique with real-time cognitive monitoring and provide practical guidance for safe and effective implementation.</p><h3>Conclusion</h3><p>Success relies on rigorous intraoperative standards to optimize functional mapping. Beyond oncological outcomes, this surgical philosophy preserves quality of life by respecting individual brain organization, reflecting a shift toward personalized functional neurooncology.</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06656-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144998506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Haemodynamic characteristics of thin-walled regions in intracranial aneurysms: intraoperative imaging and CFD analysis","authors":"Haveena Anbananthan,&nbsp;Phani Kumari Paritala,&nbsp;Jessica Benitez Mendieta,&nbsp;Han Yu,&nbsp;Tiago Guerzet Sardenberg Lima,&nbsp;Zoe Dettrick,&nbsp;Ee Shern Liang,&nbsp;Alan Coulthard,&nbsp;Zhi-Yong Li,&nbsp;Craig Winter","doi":"10.1007/s00701-025-06660-y","DOIUrl":"10.1007/s00701-025-06660-y","url":null,"abstract":"<div><h3>Background</h3><p>Identifying haemodynamic factors associated with thin-walled regions (TWRs) of intracranial aneurysms is critical for improving pre-surgical rupture risk assessment. Intraoperatively, these regions are visually distinguished by a red, translucent appearance and are considered highly rupture prone. However, current imaging modalities lack the resolution to detect such vulnerable areas preoperatively. This study aimed to determine whether thin-walled regions exhibit distinct local haemodynamic profiles compared to adjacent normal-appearing wall regions.</p><h3>Methods</h3><p>Sixteen patient-specific models of unruptured middle cerebral artery aneurysms were reconstructed from digital subtraction angiography images. Intraoperative TWRs were identified using a colour segmentation method based on Delta E metrics. Computational fluid dynamics (CFD) simulations were used to compute six haemodynamic parameters: wall shear stress (WSS), time-averaged WSS (TaWSS), oscillatory shear index (OSI), relative residence time (RRT), WSS divergence (WSSD), and pressure. Haemodynamic data were extracted from spatially localised surface patches within confirmed thin and normal regions. Linear mixed-effects models were applied to compare parameters while accounting for patient-level and intra-patient variability, using normalised values to improve model fit.</p><h3>Results</h3><p>Thin regions exhibited significantly higher WSS, TaWSS, WSSD, and pressure, and reduced RRT. WSS and TaWSS were approximately 3.3% and 2.8% higher in TWRs, respectively. WSSD was 5.4% higher and RRT was 0.3% lower, suggesting faster, more divergent flow in thin regions. Pressure was modestly but significantly elevated at + 1.3%. No significant difference was observed in OSI between regions.</p><h3>Conclusions</h3><p>Thin-walled regions in intracranial aneurysms demonstrate a distinctive haemodynamic profile characterised by stronger, sustained shear forces, greater shear divergence, and reduced residence time, suggesting a dynamic mechanical environment that promotes focal wall thinning. Our findings suggest that persistent shear-driven stress, rather than oscillatory flow, is a key haemodynamic feature of thin-walled regions and may contribute to localised aneurysm wall vulnerability.\u0000</p></div>","PeriodicalId":7370,"journal":{"name":"Acta Neurochirurgica","volume":"167 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00701-025-06660-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144998505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}