BACKGROUND AND PURPOSE: Impairment of tissue oxygenation caused by inhomogeneous microscopic blood flow distribution, the so-called capillary transit time heterogeneity, is thought to contribute to delayed cerebral ischemia after aneurysmal SAH but has so far not been systematically evaluated in patients. We hypothesized that heterogeneity of the MTT, derived from CTP parameters, would give insight into the clinical course of patients with aneurysmal SAH and may identify patients at risk of poor outcome. MATERIALS AND METHODS: We retrospectively analyzed the heterogeneity of the MTT using the coefficient of variation in CTP scans from 132 patients. A multivariable logistic regression model was used to model the dichotomized mRS outcome. Linear regression was used to eliminate variables with high linear dependence. T tests were used to compare the means of 2 groups. Furthermore, the time of the maximum coefficient of variation for MTT after bleeding was evaluated for correlation with the mRS after 6 months. RESULTS: On average, each patient underwent 5.3 CTP scans during his or her stay. Patients with high coefficient of variation for MTT presented more often with higher modified Fisher (P = .011) and World Federation of Neurosurgical Societies grades (P = .014). A high coefficient of variation for MTT at days 3–21 after aneurysmal SAH correlated significantly with a worse mRS score after 6 months (P = .016). We found no correlation between the time of the maximum coefficient of variation for MTT after bleeding and the patients’ outcomes after 6 months (P = .203). CONCLUSIONS: Heterogeneity of MTT in CTP after aneurysmal SAH correlates with the patients’ outcomes. Because the findings are in line with the pathophysiologic concept of the capillary transit time heterogeneity, future studies should seek to verify the coefficient of variation for MTT as a potential imaging biomarker for outcome.

BACKGROUND: Carotid siphon calcification (CSC) serves as a marker of atherosclerosis and therefore may influence the outcome after subarachnoid hemorrhage (aSAH). We aimed to analyze the impact of CSC on neurological outcomes, ischemia, and vasospasm. METHODS: A total of 716 patients with aSAH were treated between December 2004 and June 2016 in our central European tertiary neurovascular care center in Essen, Germany. CSC was recorded using the Woodcock scale (grades 0–3) on a computed tomography scan. Study end points included an unfavorable outcome at 6 months post-aSAH (modified Rankin Scale score ≥4), vasospasm, and early cerebral ischemia (72 hours) and delayed cerebral ischemia (delayed cerebral ischemia; >72 hours) in the follow-up computed tomography scans. The associations were adjusted for patients’ baseline characteristics and secondary complications. Finally, within a subgroup analysis, patients with and without daily aspirin intake after endovascular aneurysm occlusion were compared. RESULTS: Increasing grades of CSC were associated with lower rates of vasospasm in the anterior circulation. Severe CSC (grade 3) was independently related to the risk of an unfavorable outcome (adjusted odds ratio [aOR], 4.06 [95% CI, 1.98–8.33]; P <0.001) and early cerebral ischemia (aOR, 1.58 [95% CI, 1.03–2.43]; P =0.035) but not delayed cerebral ischemia (aOR, 1.08 [95% CI, 0.67–1.73]; P =0.763). In the aspirin subgroup analysis, the negative effect of severe CSC on functional outcome remained significant only in aSAH cases without aspirin (aOR, 5.47 [95% CI, 2.38–12.54]; P <0.001). In contrast, there was no association between severe CSC and unfavorable outcomes among individuals with daily aspirin intake (aOR, 0.84 [95% CI, 0.59–4.21]; P =0.603). CONCLUSIONS: Our data suggest CSC as a cerebrovascular risk factor resulting in higher rates of early cerebral ischemia and unfavorable outcomes after aSAH. However, by increasing arterial stiffness, CSC might lower the probability of vasospasm, which could explain the missing link between CSC and delayed cerebral ischemia. Additionally, aspirin intake seems to potentially mitigate the negative impact of CSC on aSAH outcome. Further investigations are needed to confirm the observations from the present study.

Background and Objective: Cerebral cavernous malformation (CCM) is a vascular disorder causing seizures, neurological deficits, and hemorrhagic stroke. It can be sporadic or inherited via CCM1, CCM2, or CCM3 gene mutations. Inflammation is broadly recognized as a promoter of cerebral vascular malformations. This study explores inflammatory mechanisms and differences behind CCM-related hemorrhage and epilepsy. Material and Methods: The study group comprised 28 patients, ten patients with CCM-related epilepsy, and 18 patients who clinically presented with a cerebral hemorrhage at diagnosis. All patients underwent microsurgical resection of the CCMs. Formaldehyde-fixed, paraffin-embedded tissue samples were immunohistochemically stained using a monoclonal antibody against Cyclooxygenase 2 (COX-2) (Dako, Santa Clara, CA; Clone: CX-294) and NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) (ABCAM, Cambridge, MA, USA; ab214185). MRI and clinical data were correlated with immunohistochemical findings, and the analysis was conducted utilizing the Trainable Weka Segmentation algorithm. Results: Median CCM volume was 1.68 cm³ (IQR: 0.85–3.07 cm³). There were significantly more NLRP3-positive cells (32.56% to 91.98%; mean: 65.82%, median: 68.34%; SD: ±17.70%), compared to COX-2-positive cells (1.82% to 79.69%; mean: 45.87%, median: 49.06%; SD: ±22.56%). No correlation was shown between the volume of CCMs and a hemorrhage event (p = 0.13, 95% CI: 0.99–1.02). Symptomatic brain hemorrhage showed a significantly increased inflammatory enzyme upregulation from both COX-2 (p < 0.001) and NLRP3 (p = 0.009) versus patients with symptomatic CCM-related epilepsy at first diagnosis. Conclusions: Inflammatory processes in CCMs seem to be driven by broad and multiple pathways because both COX-2 and NLRP3-driven inflammatory pathways are consistently activated. As a novelty, this study showed that patients with symptomatic hemorrhage showed upregulated inflammatory enzyme activity compared to patients with CCM-related epilepsy. No direct links between NLRP3, COX-2 expression, and radiological, pathological, or preexisting patient conditions were found.

Background and Objectives: Development of acute coronary syndrome (ACS) after aneurysmal subarachnoid hemorrhage (aSAH) strongly affects further neuro-intensive care management. We aimed to analyze the incidence, risk factors and clinical impact of ACS in aSAH patients. Materials and Methods: This retrospective analysis included 855 aSAH cases treated between 01/2003 and 06/2016. The occurrence of ACS during 3 weeks of aSAH was documented. Patients’ demographic, clinical, radiographic and laboratory characteristics at admission were collected as potential ACS predictors. The association between ACS and the aSAH outcome was analyzed as the occurrence of cerebral infarcts in the computed tomography scans and unfavorable outcome (modified Rankin scale > 3) at 6 months after aSAH. Univariable and multivariable analyses were performed. Results: ACS was documented in 28 cases (3.3%) in the final cohort (mean age: 54.9 years; 67.8% females). In the multivariable analysis, there was a significant association between ACS, an unfavorable outcome (adjusted odds ratio [aOR] = 3.43, p = 0.027) and a borderline significance with cerebral infarcts (aOR = 2.5, p = 0.066). The final prediction model for ACS occurrence included five independent predictors (age > 55 years [1 point], serum sodium < 142 mmol/L [3 points], blood sugar ≥ 170 mg/dL [2 points], serum creatine kinase ≥ 255 U/L [3 points] and gamma-glutamyl transferase ≥ 36 U/L [1 point]) and showed high diagnostic accuracy for ACS prediction (AUC = 0.879). Depending on the cumulative score value, the risk of ACS in the cohort varied between 0% (0 points) and 66.7% (10 points). Conclusions: ACS is a rare, but clinically very relevant, complication of aSAH. The development of ACS can reliably be predicted by the presented prediction model, which enables the early identification of aSAH individuals at high risk for ACS. External validation of the prediction model is mandatory.

Cerebral Cavernous Malformations (CCMs) are low-flow vascular lesions located within the central nervous system, with a reported prevalence in the general population of 0.16–0.5%. Patients with CCMs may remain asymptomatic or present new onset symptoms such as seizures or focal neurological deficits often related to the occurrence of intracerebral hemorrhage. CCM may appear sporadic or as part of familial forms linked to mutations in the CCM-gene cluster, affecting endothelial cell integrity and triggering molecular cascades, including the MEKK3/KLF2/4 signaling pathway. Recent studies have highlighted the roles of inflammatory, angiogenic, and coagulation pathways alongside the emerging evidence of a gut–brain axis influencing microbiome-driven TLR4 signaling. This systematic review aims to describe molecular biomarkers associated with CCM pathophysiology, emphasizing their potential use as diagnostic and prognostic tools. Circulating plasma biomarkers such as CRP, vitamin D, and interleukins may reflect ongoing inflammatory and endothelial processes, while some imaging biomarkers like Quantitative Susceptibility Mapping (QSM) have shown a correlation with iron deposition and vascular leakage. Leveraging both circulating and imaging biomarkers may improve the therapeutic decision-making process. Further studies are encouraged to validate these findings and to facilitate the development of personalized, evidence-based strategies for the management of CCM.

Background/Objectives: Cerebral vasospasm (CV) is a serious complication of aneurysmal subarachnoid hemorrhage (aSAH). Carotid siphon calcification (CSC) has been associated with a reduced risk of CV. This study investigates the influence of CSC on the clinical and radiographic severity of CV and functional outcome of aSAH. Methods: A total of 475 patients with aSAH treated at the University Hospital Essen (2008–2016) were analyzed retrospectively. CSC was assessed using the Woodcock score. Study endpoints were the CV severity in digital subtraction angiography, presence of CV in transcranial Doppler (TCD) ultra-sonography, occurrence of delayed ischemic neurological deficit (DIND) and the functional outcome at 6 months measured with the modified Rankin scale. Results: CSC was confirmed as an independent predictor for the occurrence (aOR 0.76; 95% CI 0.60–0.97; p = 0.025) and severity (RC −0.14; 95% CI −0.24 to −0.04; p = 0.006) of angiographic CV and development of DIND (aOR 0.76; 95% CI 0.59–0.98; p = 0.034). Only the duration (in days: RC −0.43; 95% CI −0.77 to −0.10; p = 0.010) but not the presence (aOR 0.87; 95% CI 0.68 to 1.11; p = 0.265) and severity (cerebral blood flow, in cm/s: RC +1.57; 95% CI −7.45 to +10.58; p = 0.731) of TCD CV was associated with CSC. Finally, the increasing levels of CSC were related to poorer 6-month functional outcome (RC +0.12; 95% CI +0.05 to +0.18; p < 0.001). Conclusions: CSC appears to be protective against angiographic CV and DIND, but correlates with worse overall outcome, suggesting that atherosclerosis, represented by CSC, affects cerebrovascular regulation and overall prognosis. We suggest careful evaluation of primary imaging studies for markers of atherosclerosis to identify patients at risk for CV and patients with low risk for CV but still at high risk for poor outcome.