Should Patients Be Counseled About Possible Recurrence of Perimesencephalic Subarachnoid Hemorrhage?

Recurrent perimesencephalic nonaneurysmal subarachnoid hemorrhage within a short period of time: A case report

BACKGROUND

Spontaneous subarachnoid hemorrhage (SAH) is primarily caused by a ruptured intracranial aneurysm. Perimesencephalic nonaneurysmal SAH (PNSAH) accounts for approximately 5% of all spontaneous SAH. PNSAH displays favorable prognosis. The risk of hemorrhage recurrence is low. We report a case of PNSAH recurrence, occurring within a short time after the initial episode in a patient not receiving antithrombotic or antiplatelet drugs.

CASE SUMMARY

A 66-year-old male, without any history of recent trauma or antithrombotic/ antiplatelet medication, suffered two similar episodes of sudden onset of severe headache, nausea, and vomiting. A plain head computed tomography (CT) scan showed subarachnoid blood confined to the anterior part of the brainstem. Platelet count and coagulation function were normal. PNSAH was diagnosed by repeated head CT, magnetic resonance imaging, and cerebral angiography, none of which revealed the source of SAH. The patient was discharged without focal neurological deficits. At 6-mo follow-up, the patient had experienced no sudden onset of severe headache and presented favorable clinical outcome. Studies have reported a few patients with recurrent PNSAH, originating frequently from venous hemorrhage and conventionally associated with venous abnormalities. PNSAH recurs within a short time following the initial onset of symptoms, although the possibility of re-hemorrhage is extremely rare.

CONCLUSION

PNSAH recurrence should arouse vigilance; however, the definite source of idiopathic SAH in this case report deserves further attention.

Recurrent Bleeding After Perimesencephalic Hemorrhage: Case Report and Review of the Literature

BACKGROUND

Perimesencephalic hemorrhage (PMH), a subtype of nonaneurysmal subarachnoid hemorrhage, is characterized by a typical pattern of localized hemorrhage on head computed tomography. PMH is usually associated with a benign clinical course, and a lower incidence of complications such as vasospasm and rebleeding.

CASE DESCRIPTION

We present the cases of a man aged 28 years and a woman aged 21 years with no relevant medical history who experienced recurrent, spontaneous episodes of PMH within the course of 7 days and 29 months. No precipitating causes were identified.

CONCLUSIONS

There are only a couple of case reports of recurrent PMH, some of which were defined questionably. We review the reported cases and discuss the possible causes and long-term outcomes. Neurointerventionalists and neurosurgeons should be aware that the risk of recurrent hemorrhage of PMH does exist, although it is rather low. Even after early or late rebleeding, prognosis of PMH is excellent.

Recurrent Bleeding After Perimesencephalic Hemorrhage

BACKGROUND

Perimesencephalic hemorrhage (PMH) is a type of subarachnoid hemorrhage with excellent long-term outcomes. Only 1 well-documented case of in-hospital rebleeding after PMH is described in the literature, which occurred after initiating antithrombotic treatment because of myocardial ischemia. We describe a patient with PMH without antithrombotic treatment who had 2 episodes of recurrent bleeding on the day of ictus. To validate the radiologic findings, we conducted a case-control study. Six neuroradiologists and 2 neuroradiology fellows performed a blinded assessment of serial unenhanced head computed tomography (CT) scans of 8 patients with a perimesencephalic bleeding pattern (1 index patient, 6 patients with PMH, 1 patient with perimesencephalic bleeding pattern and basilar artery aneurysm) to investigate a potential increase in amount of subarachnoid blood.

CASE DESCRIPTION

A 56-year-old woman with a perimesencephalic bleeding pattern and negative CT angiography had 2 episodes after the onset headache with a sudden increase of the headache. Blinded assessment of serial head CT scans of 8 patients with a perimesencephalic bleeding pattern identified the patient who was clinically suspected to have 2 episodes of recurrent bleeding to have an increased amount of subarachnoid blood on 2 subsequent CT scans.

CONCLUSIONS

Recurrent bleeding after PMH may also occur in patients not treated with antithrombotics. Even after early rebleeding, the prognosis of PMH is excellent.