Non-aneurysmal spontaneous subarachnoid hemorrhage: perimesencephalic versus non-perimesencephalic

Abstract

Objective To compare the clinical evolution of perimesencephalic subarachnoid hemorrhage and non-perimesencephalic subarachnoid hemorrhage.Methods The study was conducted retrospectively in a tertiary hospital center in the north region of Portugal. Included patients had no identifiable cause for subarachnoid hemorrhage. Several epidemiologic, clinical and imaging aspects were statistically analyzed, taking into account the differences in perimesencephalic subarachnoid hemorrhage and non-perimesencephalic subarachnoid hemorrhage.Results Sixty-two patients met the inclusion criteria (46.8% - perimesencephalic subarachnoid hemorrhage; 53.2% - non-perimesencephalic subarachnoid hemorrhage). Demographic and clinical background characteristics were similar in both groups. Complications were more frequent in patients with non-perimesencephalic subarachnoid hemorrhage - 84.8% of the patients had at least one complication versus 48.3% in perimesencephalic subarachnoid hemorrhage. Vasospasm, infection and hydrocephaly were the most common complications (each was detected more frequently in the non-perimesencephalic subarachnoid hemorrhage group than in perimesencephalic subarachnoid hemorrhage group). Two patients died, both had a non-perimesencephalic subarachnoid hemorrhage. The median inpatient time was longer in the non-perimesencephalic subarachnoid hemorrhage group (21 versus 14 days). No incidents of rebleeding were reported during the follow-up period (mean time of 15 ± 10.3 months).Conclusion Perimesencephalic subarachnoid hemorrhage and non-perimesencephalic subarachnoid hemorrhage are two different entities that have different clinical outcomes, namely in terms of complication rate and median inpatient time. The management of these patients should respect this difference to improve treatment and optimize health care resources.

Non-aneurysmal subarachnoid hemorrhage: When is a second angiography indicated?

“…One study reported angiographic vasospasm in 33.3% patients with nPMSAH versus 13.8% patients with PMSAH ( p = 0.073). 31 This is in line with the present study, which showed angiographic vasospasm in 25.7% patients with nPMSAH versus 7.7% patients with PMSAH ( p = 0.069). In addition, hydrocephalus was mainly seen in patients with nPMSAH (57.1%) as well, compared to PMSAH (5.1%) ( p < 0.0001), which is in accord with the literature as well.…”

“…In addition, hydrocephalus was mainly seen in patients with nPMSAH (57.1%) as well, compared to PMSAH (5.1%) (p < 0.0001), which is in accord with the literature as well. 8,31 Nine (25.7%) patients in the nPMSAH group subsequently required a placement of VPS, compared to two (5.1%) in the group with PMSAH (p ¼ 0.014).…”

The Yield of Repeat Angiography in Angiography-Negative Spontaneous Subarachnoid Hemorrhage

“…The clinical outcome in angionegative SAH is excellent with a low risk of vasospasm and hydrocephalus. 3 Therefore, identifying the cause of SAH is crucial. An undetected aneurysmal SAH may be associated with rebleeding risk, resulting in mortality and morbidity.…”

“…Patients with angionegative SAH have superior survival and overall outcomes. 3 Studies have shown that the initial angiogram is negative for the cause of SAH in 15 to 20% of the patients. 4 5 Depending on the pattern of blood distribution, SAH can be divided into two categories: (1) perimesencephalic SAH (PM-SAH), which is restricted to PM or prepontine cistern; and (2) nonperimesencephalic SAH (nPM-SAH) which is a diffuse variety with bleeding extending into the anterior interhemispheric or Sylvian cisterns along with other basal cisterns.…”

Nonaneurysmal Perimesencephalic Subarachnoid Hemorrhage as an Atypical Initial Presentation of Cerebral Venous Sinus Thrombosis: A Case Report

“…Because aneurysmal ruptures are rarely associated with PNSAH like bleeding patterns, full cerebral angiography is recommended by radiologists to avoid missing any vascular malformations or vertebrobasilar aneurysms. If the angiography is negative, hemorrhage bleeding in the initial CT scan is essential to establish a perimesencephalic pattern [ 11 ].…”