Tatit, Rafael Trindade

OBJECTIVE The objective was to synthesize denominator-based evidence on indications, techniques, and postoperative outcomes of cervicomedullary decompression (CMD), spinal canal stenosis surgery, and cerebrospinal fluid (CSF) diversion for hydrocephalus in achondroplasia. METHODS This systematic review followed PRISMA 2020 and was prospectively registered (PROSPERO CRD42025626915). MEDLINE (via PubMed), Embase, Scopus, Web of Science, and the Cochrane Library were searched from inception through November 2025. The authors included observational studies of patients with achondroplasia who underwent CMD, spinal canal stenosis surgery, or CSF diversion for hydrocephalus with extractable outcomes and definable denominators. Two reviewers independently screened studies and extracted data. Risk of bias was assessed using ROBINS-I. Random-effects single-arm meta-analyses were performed for prespecified endpoints (any improvement, complete resolution, and mortality) only in cohorts with fully categorizable symptom status. RESULTS The authors included 38 observational studies (1442 patients): 18 CMD studies with 600 patients, 18 spinal stenosis studies with 686 patients, and 4 hydrocephalus studies with 156 patients. No study was at low risk of bias. For CMD (mean age 3.5 years; mean follow-up 27.8 months), any improvement was observed in 93% (95% CI 84%–97%) of patients and complete resolution in 44% (95% CI 16%–77%), and pooled mortality was 0% (95% CI 0%–5%). For spinal stenosis (mean age 36.6 years; mean follow-up 53.1 months), any improvement was observed in 92% (95% CI 78%–97%) and complete resolution in 30% (95% CI 16%–51%), and pooled mortality was 1% (95% CI 0%–2%). Hydrocephalus management was predominantly ventriculoperitoneal shunting (74.4%), with endoscopic third ventriculostomy in 23.1%, but symptom outcomes were rarely classifiable (9.6%), precluding strategy-level inference. CONCLUSIONS CMD and spinal stenosis surgery were frequently followed by symptom improvement in published series, whereas complete resolution was variably defined and inconsistently reported. Hydrocephalus studies described practice patterns but lacked outcome reporting adequate for comparing diversion strategies. Validated patient-reported outcomes were rarely reported, limiting inference on health-related quality of life.

The effect of induced hypertension (iHTN) on functional outcomes in noncardioembolic acute ischemic stroke (AIS) with early neurological deterioration remains unclear. We performed a systematic review and meta-analysis evaluating the safety and efficacy of iHTN vs medical management. A literature search of PubMed/MEDLINE, Web of Science, Ovid Embase, and Scopus from inception through November 6th, 2025. The protocol was registered in PROSPERO (CRD420261282211). Studies evaluating iHTN within 72 h of AIS onset and reporting 90-day functional independence (modified Rankin Scale [mRS] 0-2) were included. Safety outcome was hemorrhagic transformation. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were estimated using random-effects model based on Restricted Maximum-Likelihood (REML) methods. Three studies were included, comprising 366 patients (iHTN, n = 180; control, n = 186). Mean age was 65.8 ± 11.8 years, 60.9% were men, and the mean initial NIHSS was 5.4 ± 3.5. Target systolic blood pressure (SBP) was a 15-25% increase from baseline SBP using phenylephrine. Functional independence at 90-days occurred more often in the iHTN group than in controls (68.8% vs 50.5%; RR = 1.37; 95% CI, 1.09-1.73; P = 0.007). Hemorrhagic transformation was uncommon and did not differ significantly between groups (3.3% vs 0.5%; RR = 2.08; 95% CI, 0.05-88.07; P = 0.70). In our study, phenylephrine-induced hypertension was associated with greater 90-day functional independence in selected AIS subtypes,without a significant increase in hemorrhagic transformation. However, the limited studies, predominance of retrospective designs, exclusively Asian cohorts, and heterogeneity in treatment protocols and populations warrant cautious interpretation and underscore the need for larger multicenter RCTs.

Introduction Although Valsalva maneuvers and strenuous exercise are commonly discouraged in patients with intracranial aneurysms (IAs), the cerebrovascular stress they induce remains poorly characterized. To our knowledge, no prior review has systematically quantified their effects on hemodynamic surrogates of rupture risk. Objective To characterize the acute intracranial hemodynamic effects of strenuous physical activity and Valsalva maneuvers in individuals with and without IAs. Methods We searched PubMed, Embase, Scopus, Web of Science, and Cochrane (February 2025; PROSPERO ID: CRD42025637608) following PRISMA. Eligible studies reported acute changes in SBP, ICP, central venous pressure (CVP), cerebrovascular transmural pressure (CVTMP), middle cerebral artery (MCA) velocity, or CFD‐derived parameters (wall shear stress [WSS], oscillatory shear index [OSI], relative residence time [RRT]) in response to physical exertion or Valsalva. Populations included individuals with or without IAs. Acute neurological symptoms were also reviewed. Results From 2,859 records, 14 studies met inclusion criteria. Eight studies assessed real‐time hemodynamic responses during exercise (91 participants without IAs). Three studies (n=39) showed that resistance exercise increased SBP (mean Δ+21.8 mmHg). Two studies (n=22) showed significant MAP elevation (mean Δ+24.7 mmHg). When combined with a Valsalva maneuver, SBP increased further (mean Δ+26 mmHg; range 20–30). Three studies (n=38) evaluating isolated Valsalva identified significant ICP elevation (mean Δ+15 mmHg; range 5.7–24.3), primarily driven by CVP increases (mean Δ+52.0 mmHg; range 39–56). Breath‐holding during exertion reduced MCA velocity (mean Δ–11.6 cm/s), while continuous ventilation preserved more stable flow. In seven patients, resistance exercise without Valsalva increased CVTMP by 24.5%. In contrast, Valsalva alone raised ICP and CVP without increasing SBP, yielding a CVTMP 11% lower than during exercise alone. These paired observations suggest that Valsalva may transiently offset exercise‐induced transmural stress by raising ICP alongside SBP. However, this effect may be time‐limited and reverse during early recovery—when SBP remains elevated as ICP quickly normalizes—potentially producing a CVTMP rebound above exercise‐only levels. Six CFD studies (11 aneurysms; diameter 6.3–23 mm; 2 ruptured) reported exercise‐related increases in time‐averaged WSS (mean +21.7%, range –4.4% to +50%) and peak WSS (mean +382.3%, range +100% to +628%). Exercise‐induced changes in heart rate and flow pulsatility led to complex redistributions of intra‐aneurysmal WSS, potentially exposing the aneurysmal wall to focal mechanical stress. Conclusion Resistance exercise, especially with breath‐holding, provokes dynamic, time‐sensitive cerebrovascular stress. Valsalva maneuver may transiently lower CVTMP during effort, yet its release with lingering SBP elevation can precipitate delayed transmural pressure surges. The proposed biphasic effect of Valsalva offers a novel conceptual framework for prospective. Our findings underscore the need to define safe, individualized activity thresholds for patients with IAs with patient‐specific validation integrating concurrent physiology and CFD to reduce the risk of IA growth and rupture.

Introduction The risk of aneurysmal subarachnoid hemorrhage (aSAH) during exercise is not well quantified. We assessed temporal clustering of aSAH around physical exertion and around Valsalva‐like activities (defecation or urination). Objectives To estimate the proportion of aSAH cases temporally linked to strenuous activities using reported exposure‐to‐onset window uwing within‐person odds of rupture from case‐crossover studies. Methods We searched PubMed/MEDLINE, Embase, Scopus, Web of Science, and the Cochrane Library from inception through January 2025, and hand‐searched reference lists (PRISMA‐aligned; PROSPERO CRD42025637608). Eligible studies reported the activity at aSAH onset or within a defined pre‐onset window. Exposures were analyzed separately (exertion; defecation/urination). Primary proportional estimates used each study's own exposure‐to‐onset window as reported. To improve comparability, subgroup analysis was performed with only a prespecified subset pooled consecutive case series that explicitly used a ≤2‐hour window between the index activity and aSAH. Within‐person odds ratios (ORs) were abstracted from case‐crossover studies. Risk of bias for observational exposure studies was assessed with ROBINS‐E by two independent reviewers. Results Sixteen studies (published 1980–2022) from 10 countries were included with 5,815 cases of aSAH (mean age 55 years; 60.6% female). Designs comprised 10 case series, 3 case reports, 2 case‐crossover studies, and 1 case‐control study. Activity‐at‐onset was recorded for 4,219/5,815 (72.6%); among these 4,219 patients, mean age was 52.7 years. Using each study's reported window, 308/4,219 (7.3%) aSAH occurred during or within the study‐defined window after physical exertion, and 387/4,219 (9.2%) during/within the window after defecation or urination 695/4,219 (16.5%) were temporally linked to either exposure. In the subset of 10 consecutive case series restricted to ≤2 hours, 275 (5.4%) were linked to exertion and 385 (7.6%) to defecation/urination (combined 660; 13.0%). Study‐specific proportions ranged from 0.8–21.3% for exertion and 2.0–15.4% for defecation/urination. Two case‐crossover studies reported higher within‐person odds of rupture after moderate‐to‐vigorous exertion (OR 2.4–2.7). Temporal clustering of aSAH around exertion or straining was observed in 13–17% of cases, depending on dataset and inclusion criteria. Conclusions Although this relatively high rate of temporal association between aSAH and exercise might suggest an increased risk of aneurysm rupture during strenuous activity, variable definitions and unstated exposure‐to‐onset windows do not permit causal inference. Prospective or registry‐embedded case‐crossover studies using standardized exposure definitions (intensity, duration) and objective exposure capture are needed to refine immediate‐risk estimates and identify patient‐level susceptibility modifiers.

BACKGROUND AND IMPORTANCE: Basilar artery fenestration aneurysms (BAFAs) present significant clinical challenges because of their high rupture risk and complex anatomy. Comprehensive management strategies are required, including thorough vascular assessment and post-treatment surveillance. Integration of complementary analyses such as computational fluid dynamics (CFD) holds promise in facilitating preoperative planning for these intricate lesions. CLINICAL PRESENTATION: A 60-year-old female was diagnosed with a BAFA during evaluation for headaches. Digital subtraction angiography revealed the aneurysm projecting posteriorly with a neck predominantly based on the right limb of the fenestration. After initial treatment with a pipeline embolization device, the aneurysm remained patent, requiring further treatment. A secondary approach with stent-assisted loose-packing coil embolization was then performed, resulting in complete occlusion of the aneurysm. Analysis of pretreatment 3-dimensional rotational angiogram images with CFD provided critical hemodynamic insights. It identified that 38.89% of the aneurysm area was exposed to low wall shear stress (WSS) and 11.5% was exposed to high WSS, indicating a high rupture risk profile with significant areas of both low and high WSS. In addition, low WSS was observed in regions corresponding to daughter sacs, suggesting a higher rupture risk. Streamline analysis indicated increased inflow through the right vertebral artery and the right limb of the fenestration, supporting the initial angiographic impression and guiding the choice of therapeutic strategy. CONCLUSION: This is the first study to analyze the morphology and pretreatment hemodynamics of a BAFA using CFD, illustrating the potential for future development of individualized therapeutic approach–based CFD in complex aneurysms.

Background: We present five patients with remodeling of the adult circle of Willis in response to flow diverter stents (FDSs) at the anterior communicating artery (AComA) and the posterior communicating artery (PComA). The observed changes provide a paradigm of how flow change can institute anatomic changes in the adult circle of Willis vasculature. Case Description: In the first two cases, after placement of the FDS covering the AComA, there was an increase in size and flow of the contralateral A1-anterior cerebral artery which had previously been hypoplastic. In one of the cases, this led to the filling of the aneurysm and required placement of coils within the lesion which was curative. In case three, the FDS effect led to asymptomatic occlusion of the PComA and associated aneurysm without change of the ipsilateral P1-segement of posterior-cerebral-artery (P1-PCA) caliber. In the fourth case, the FDS covering an aneurysm with a fetal PCA arising from its neck resulted in significant reduction of the aneurysm size, persistent flow and caliber of the fetal PCA, and the hypoplastic ipsilateral P1-PCA. Finally, in the fifth case, after FDS occlusion of the PComA and aneurysm there was increasement in diameter of the ipsilateral P1-PCA that was previously hypoplastic. Conclusion: The use of FDS can affect vessels covered by the device and other arteries of the circle of Willis adjacent to the FDS. The phenomena illustrated in the hypoplastic branches appear to be a compensatory response to the hemodynamic changes induced by the divertor and to the altered flow in the circle of Willis.