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Updated: May 20, 2026
09:14
Pre-Chiasmatic, Single Injection of Autologous Blood to Induce Experimental Subarachnoid Hemorrhage in a Rat Model
Published on: June 18, 2021
Isolated trochlear nerve palsy with perimesencephalic subarachnoid haemorrhage
Koji Adachi1, Kouhei Hironaka, Hisaharu Suzuki
1Department of Neurosurgery, Nippon Medical School Musashi-Kosugi Hospital, Kawasaki, Japan. adachi@nms.ac.jp
BMJ Case Reports
|July 11, 2012
Summary
Perimesencephalic subarachnoid hemorrhage typically causes minor symptoms. This case highlights a rare instance where bleeding in the quadrigeminal cistern led to isolated trochlear nerve palsy.
Area of Science:
- Neurology
- Neurosurgery
- Radiology
Background:
- Perimesencephalic subarachnoid hemorrhage (PSAH) commonly presents with meningeal signs.
- It is often associated with a good prognosis and minimal neurological deficits.
Observation:
- A 71-year-old male with diabetes and myocardial infarction presented with diplopia.
- CT imaging revealed subarachnoid hemorrhage localized to the left quadrigeminal cistern.
- Clinical examination confirmed isolated left trochlear nerve palsy.
Findings:
- Neuroimaging confirmed perimesencephalic subarachnoid hemorrhage.
- The presence of a dense clot in the quadrigeminal cistern was identified as a potential cause.
- The volume of hemorrhage correlated with the observed neurological symptoms.
Implications:
- This case expands the known clinical spectrum of PSAH.
- It suggests a potential mechanism for trochlear nerve palsy in the context of localized quadrigeminal cistern hemorrhage.
- Highlights the importance of detailed neuroimaging in PSAH to identify potential causes of specific cranial nerve deficits.
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