Current status of perimesencephalic non-aneurysmal subarachnoid hemorrhage

Nonaneurysmal perimesencephalic subarachnoid hemorrhage on noncontrast head CT: An accuracy, inter-rater, and intra-rater reliability study

BACKGROUND AND PURPOSE

To evaluate the reliability and accuracy of nonaneurysmal perimesencephalic subarachnoid hemorrhage (NAPSAH) on Noncontrast Head CT (NCCT) between numerous raters.

MATERIALS AND METHODS

45 NCCT of adult patients with SAH who also had a catheter angiography (CA) were independently evaluated by 48 diverse raters; 45 raters performed a second assessment one month later. For each case, raters were asked: 1) whether they judged the bleeding pattern to be perimesencephalic; 2) whether there was blood anterior to brainstem; 3) complete filling of the anterior interhemispheric fissure (AIF); 4) extension to the lateral part of the sylvian fissure (LSF); 5) frank intraventricular hemorrhage; 6) whether in the hypothetical presence of a negative CT angiogram they would still recommend CA. An automatic NAPSAH diagnosis was also generated by combining responses to questions 2-5. Reliability was estimated using Gwet's AC1 (κG), and the relationship between the NCCT diagnosis of NAPSAH and the recommendation to perform CA using Cramer's V test. Multi-rater accuracy of NCCT in predicting negative CA was explored.

RESULTS

Inter-rater reliability for the presence of NAPSAH was moderate (κG = 0.58; 95%CI: 0.47, 0.69), but improved to substantial when automatically generated (κG = 0.70; 95%CI: 0.59, 0.81). The most reliable criteria were the absence of AIF filling (κG = 0.79) and extension to LSF (κG = 0.79). Mean intra-rater reliability was substantial (κG = 0.65). NAPSAH weakly correlated with CA decision (V = 0.50). Mean sensitivity and specificity were 58% (95%CI: 44%, 71%) and 83 % (95%CI: 72 %, 94%), respectively.

CONCLUSION

NAPSAH remains a diagnosis of exclusion. The NCCT diagnosis was moderately reliable and its impact on clinical decisions modest.

The diagnostic yield of repeat computed tomography angiography in cases of spontaneous subarachnoid haemorrhage after negative initial digital subtraction angiography

Purpose

It is currently unclear how useful repeat computed tomography angiography (CTA) is in spontaneous subarachnoid haemorrhage (SAH) patients after negative initial digital subtraction angiography (DSA). The purpose of this study is to assess the yield of repeat CTA for the detection of causative vascular lesions in patients with SAH in whom there has been a negative initial DSA.

Material and methods

This observational retrospective study was carried out from January 2013 to July 2022 at a single institution. Analysis of the SAH pattern on unenhanced CT showed that patients were divided into perimesencephalic SAH and diffuse SAH groups. A repeat CTA was performed on all spontaneous SAH patients who had a nega-tive initial CTA and DSA within a 2-week period. An interventional neuroradiologist and a diagnostic radiologist examined all images to search for causative vascular abnormalities.

Results

Forty-seven patients were included in our study, with a median age of 55 years and a range of 28-81 years. Thirty-seven had diffuse SAH (66%), and 16 had perimesencephalic SAH (34%). The repeat CTA revealed 2 causa-tive vascular lesions (a right PICA aneurysm and a mycotic aneurysm) in 2 separate patients (yield of 4.3%), both of whom had diffuse SAH (yield of 6.5%). In retrospect, none of these vascular lesions were evident in the initial CTA and DSA. No evidence of re-bleeding was observed in the follow-up period.

Conclusions

It is beneficial to repeat CTA when evaluating patients with diffuse SAH who initially present with nega-tive initial DSA. For occult aneurysms, the diagnostic yield of the follow-up CTA is 6.5%.

Stroke Unit as an alternative to Intensive Care Unit for initial hospital admission of low-grade non-aneurysmal subarachnoid haemorrhage: A safety and cost-minimisation analysis

INTRODUCTION

Stroke Units (SU) have been suggested as an alternative to Intensive Care units (ICU) for initial admission of low-grade non-aneurysmal spontaneous subarachnoid haemorrhage (naSAH). We hypothesised that the incidence of in-hospital complications and long-term clinical outcomes in low-grade naSAH patients would be comparable in both settings, and that a cost-minimisation analysis would favour the use of SU.

PATIENTS AND METHODS

Retrospective, single-centre study at a third-level stroke-referral hospital, including low-grade spontaneous naSAH patients with WFNS 1-2. Primary outcomes were death and functional status at 3 months. Secondary outcomes were incidence of in-hospital major neurological and systemic complications. Additionally, a cost-minimisation analysis was conducted to estimate the average cost savings that could be achieved with the most efficient approach.

RESULTS

Out of 96 naSAH patients, 30 (31%) were initially admitted to ICU and 66 (69%) to SU. Both groups had similar demographic and radiological features except for a higher proportion of WFNS 2 in ICU subgroup. There were no statistically significant differences between ICU and SU-managed subgroups in death rate (2 (7%) and 1 (2%), respectively), functional outcome at 90 days (28 (93%) and 61 (92%) modified Rankin Scale 0-2) or neurological and systemic in-hospital complications. Cost-minimisation analysis demonstrated significant monetary savings favouring the SU strategy.

DISCUSSION AND CONCLUSION

Initial admission to the SU appears to be a safe and cost-effective alternative to the ICU for low-grade naSAH patients, with comparable clinical outcomes and a reduction of hospitalisation-related costs. Prospective multicenter randomised studies are encouraged to further evaluate this approach.

Comment on Roman-Filip et al. Non-Aneurysmal Perimesencephalic Subarachnoid Hemorrhage: A Literature Review. Diagnostics 2023, 13, 1195

We would like to congratulate Roman-Filip et al. on their recent review on perimesencephalic hemorrhages [...].

Clinical outcome and prognostic factors of patients with non-traumatic angiography-negative subarachnoid hemorrhage

Purpose

The cause of spontaneous subarachnoid hemorrhage (SAH) is unknown in 10% of cases. The aim of this study was to demonstrate the characteristics of patients with angiography-negative subarachnoid hemorrhage (anSAH) and to analyze factors influencing the clinical outcome in patients suffering from anSAH.

Methods

A retrospective cohort of 75 patients with anSAH [26 perimesencephalic (pmSAH) and 49 non-perimesencephalic SAH (npmSAH)] admitted between January 2016 and June 2022 was included. We analyzed demographic, clinical data and 6-month functional outcomes. Enter regression analysis was performed to identify factors associated with outcomes.

Results

Unfavorable outcome was achieved in 10 of 75 patients (13.3%). Unfavorable outcome was associated with senior adults (p = 0.008), Hijdra cistern score (HCS) elevation (p = 0.015), long-time lumbar cistern continuous drainage (LCFD; p = 0.029) and hydrocephalus (p = 0.046). The only significant risk factor for unfavorable outcome after npmSAH was the HCS (OR 1.213 (95%CI 1.007-1.462), p = 0.042).

Conclusion

Our study provides valuable information on both SAH patterns and functional outcome in patients suffering from anSAH and should be taken into consideration during management of these patients.

Non-Aneurysmal Perimesencephalic Subarachnoid Hemorrhage: A Literature Review

Spontaneous non-aneurysmal subarachnoid haemorrhage (NAPMSAH) (addressing point 1) is a relatively rare occurrence in clinical settings as it is rarely misdiagnosed and usually involves a significantly better prognosis than the classical aneurysmal pattern. We hereby focused on a comprehensive analysis of this distinct pathological entity with the purpose of analysing possible pathophysiological entities, outcomes and treatment options involving this diagnosis with a focus on demographical, epidemiological and clinical data. The clinical setting includes focal neurological signs related to the anatomical structures, while computer tomography followed by tomographic angiography are the most common diagnosis tools, with a typical hyperdense lesion involving the midbrain, fourth ventricle and subthalamic areas without an angiographic correspondent, such as an aneurysmal pathology. Further investigations can also be used to highlight this diagnosis, such as interventional angiography or magnetic resonance imaging. Given the rarity of this condition and its relatively better prognosis, treatment options usually remain conservative. In the present review, the main characteristics of NAPMSAH are discussed.

Acute Multidisciplinary Management of Aneurysmal Subarachnoid Hemorrhage (aSAH)

Aneurysmal subarachnoid hemorrhage is a life-threatening, neurological emergency characterized by accumulation of blood in the subarachnoid space due to a ruptured aneurysm. Over the past several decades, improvements in the clinical management of aneurysmal subarachnoid hemorrhage have led to better patient outcomes. However, aneurysmal subarachnoid hemorrhage is still associated with high morbidity and mortality. During the acute phase of aneurysmal subarachnoid hemorrhage and prior to the definitive management of the aneurysm, numerous medical emergencies, such as elevated intracranial pressure and cerebral vasospasm, must be effectively managed to ensure the best possible neurological outcome. Early and rapid open communication between the clinical specialties caring for the aneurysmal subarachnoid hemorrhage patient is vital for rapid data collection, decision-making, and definitive treatment. In this narrative review, we aim to present the current guidelines for the multidisciplinary acute management of aneurysmal subarachnoid hemorrhage.