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.