Risk identification for the development of large-artery vasospasm after aneurysmatic subarachnoid hemorrhage - a multivariate, risk-, and location-adjusted prediction model.

BACKGROUND: Vasospasm of the large cerebral arteries (CVS) after aneurysmatic subarachnoid hemorrhage (aSAH) reduces cerebral perfusion and causes delayed cerebral ischemia. Although endovascular spasmolysis shows convincing angiographic results, patients often do not improve in outcome. Delayed recognition of CVS contributes substantially to this effect. Therefore, this study aimed to confirm established and to identify unknown risk factors for CVS, which can be used for risk stratification. METHODS: In this monocentric, retrospective cohort study of 853 patients with aSAH, we compared demographics, clinical, and radiographic parameters at the time of aneurysm occlusion between patients who developed CVS and those who did not. Significant cohort differences were included as predictors in a multivariate analysis to address confounding. Logistic regression models were used to determine odds ratios (ORs) for the presence of CVS for each predictor. RESULTS: Of the 853 patients treated with aSAH, 304 (32%) developed CVS. In the univariable analysis, CVS was significantly associated with young age, female sex, aneurysm location, modified Fisher score, Barrow Neurological Institute (BNI) score, and surgical interventions. In the multivariable regression analysis, we identified BNI score (OR 1.33, 95% CI 1.11 to 1.58, p=0.002), decompressive craniectomy (OR 1.93, 95% CI 1.22 to 3.04, p=0.005), and aneurysm clipping (OR 2.22, 95% CI 1.50 to 3.29, p<0.001), as independent risk factors. CONCLUSIONS: Young female patients with high BNI scores who undergo surgical interventions are more likely to develop CVS and should therefore be monitored most intensively after aneurysm occlusion.

VPS dependency after aneurysmal subarachnoid haemorrhage and influence of admission hyperglycaemia.

Introduction: Hydrocephalus after aneurysmal subarachnoid haemorrhage (aSAH) is a common complication which may lead to insertion of a ventriculoperitoneal shunt (VPS). Our aim is to evaluate a possible influence of specific clinical and biochemical factors on VPS dependency with special emphasis on hyperglycaemia on admission. Patients and methods: Retrospective analysis of a monocentric database of aSAH patients. Using univariable and multivariable logistic regression analysis we evaluated factors influencing VPS dependency, with a special focus on hyperglycaemia on blood sample within 24 h of admission, dichotomised at 126 mg/dl. Factors evaluated in the univariable analysis were age, sex, known diabetes, Hunt and Hess grade, Barrow Neurological Institute scale, treatment modality, extra-ventricular drain (EVD) insertion, complications (rebleeding, vasospasm, infarction, decompressive craniectomy, ventriculitis), outcome variables and laboratory parameters (glucose, C-reactive protein, procalcitonin). Results: We included 510 consecutive patients treated with acute aSAH requiring a VPS (mean age 58.2 years, 66% were female). An EVD was inserted in 387 (75.9%) patients. In the univariable analysis, VPS dependency was associated with hyperglycaemia on admission (OR 2.56, 95%CI 1.58-4.14, p < 0.001). In the multivariable regression analysis after stepwise backward regression, factors associated with VPS dependency were hyperglycaemia >126 mg/dl on admission (OR 1.93, 95%CI 1.13-3.30, p = 0.02), ventriculitis (OR 2.33, 95%CI 1.33-4.04, p = 0.003), Hunt and Hess grade (overall p-value 0.02) and decompressive craniectomy (OR 2.68, 95%CI 1.55-4.64, p < 0.001). Conclusion: Hyperglycaemia on admission was associated with an increased probability of VPS placement. If confirmed, this finding might facilitate treatment of these patients by accelerating insertion of a permanent draining system.

Duration between aneurysm rupture and treatment and its association with outcome in aneurysmal subarachnoid haemorrhage.

Timely treatment of aneurysmal subarachnoid haemorrhage (aSAH) is key to prevent further rupture and poor outcome. We evaluated complications and outcome adjusting for time from haemorrhage to treatment. Retrospective analysis of aSAH patients admitted between 2006 and 2020. Data was collected using standardized case report forms. We compared risk factors using multivariable logistic regression. We included 853 patients, 698 (81.8%) were treated within 24 h. Patients with higher Hunt and Hess grades were admitted and treated significantly faster than those with lower grades (overall p-value < 0.001). Fifteen patients (1.8%) rebled before intervention. In the multivariable logistic analysis adjusting for timing, Barrow Neurological Institute score and intracerebral haemorrhage were significantly associated with rebleeding (overall p-value 0.006; OR 3.12, 95%CI 1.09-8.92, p = 0.03, respectively) but timing was not. Treatment > 24 h was associated with higher mortality and cerebral infarction in only the subgroup of lower grades aSAH (OR 3.13, 1.02-9.58 95%CI, p-value = 0.05; OR 7.69, 2.44-25.00, p-value < 0.001, respectively). Therefore treatment > 24 h after rupture is associated with higher mortality and cerebral infarction rates in lower grades aSAH. Delay in treatment primarily affects lower grade aSAH patients. Patients with lower grade aSAH ought to be treated with the same urgency as higher-grade aSAH.

Treatment during cerebral vasospasm phase-complication association and outcome in aneurysmal subarachnoid haemorrhage.

BACKGROUND: Aneurysm treatment during cerebral vasospasm (CVS) phase is frequently considered as particularly dangerous, mainly because of the risk of cerebral infarct. OBJECTIVE: We aimed to evaluate the risk of aneurysmal subarachnoid haemorrhage (aSAH)-specific complications and functional outcome in patients treated during CVS phase. METHODS: We retrospectively analysed a large, retro- and prospectively collected database of aSAH patients admitted to our department between March 2006 and March 2020. We conducted a uni- and multivariable logistic regression analysis to evaluate influencing factors on rebleeding, cerebral infarct, Glasgow Outcome Score (GOS) at discharge and mortality and assessed the rate of angiographic vasospasm on admission. RESULTS: We included 853 patients. The majority of patients were female (66.6%), mean age was 57.3 years. Out of 853 included patients, 92 (10.8%) were treated during CVS phase, 312 (36.6%) underwent clipping and 541 (63.4%) endovascular treatment. Treatment during CVS phase was significantly associated with cerebral infarct in the multivariable logistic regression analysis, unrelated to the nature of intervention (OR 2.42, 1.29-4.54 95% CI p-value = 0.006). However, patients treated during CVS phase did not have increased risk of unfavourable outcome by GOS on discharge. In addition, they did not have a higher rate of rebleeding or mortality. CONCLUSIONS: Treatment during CVS phase was significantly associated with a higher rate of cerebral infarct as confirmed by imaging. This did not reflect on GOS on discharge, rebleeding, or mortality. Aneurysm treatment during CVS phase is relatively safe and should not be postponed due to the risk of rebleeding and subsequent devastating deterioration.

The Medial Ventrothalamic Circuitry: Cells Implicated in a Bimodal Network.

Previous avian thalamic studies have shown that the medial ventral thalamus is composed of several nuclei located close to the lateral wall of the third ventricle. Although the general connectivity is known, detailed morphology and connectivity pattern in some regions are still elusive. Here, using the intracellular filling technique in the chicken, we focused on two neural structures, namely, the retinorecipient neuropil of the n. geniculatus lateralis pars ventralis (GLv), and the adjacent n. intercalatus thalami (ICT). We found that the GLv-ne cells showed two different neuronal types: projection cells and horizontal interneurons. The projection cells showed variable morphologies and dendritic arborizations with axons that targeted the n. lentiformis mesencephali (LM), griseum tectale (GT), ICT, n. principalis precommissuralis (PPC), and optic tectum (TeO). The horizontal cells showed a widespread mediolateral neural process throughout the retinorecipient GLv-ne. The ICT cells, on the other hand, had multipolar somata with wide dendritic fields that extended toward the lamina interna of the GLv, and a projection pattern that targeted the n. laminaris precommissuralis (LPC). Together, these results elucidate the rich complexity of the connectivity pattern so far described between the GLv, ICT, pretectum, and tectum. Interestingly, the implication of some of these neural structures in visuomotor and somatosensory roles strongly suggests that the GLv and ICT are part of a bimodal circuit that may be involved in the generation/modulation of saccades, gaze control, and space perception.