Meningioma of cerebellopontine angle
. A report of 41 cases.
Acoustic neuroma is the most frequent benign tumour at cerebellopontine angle
.1 It accounts for 8 10% of all primary intracranial tumours and 80% of Cerebellopontine angle
tumours.2 Meningioma constitutes 5 10% of Cerebellopontine angle
tumours with rare tumours constituting only a small percentage out of which epidermoid cyst is the most frequent.3 Acoustic neuroma is a benign tumor arising from Schwann cells.4 It is usually diagnosed in adults with mean age ranging from 46 58 years with clinical incidence of 10 15%/ million / year.5 The tumor is generally composed of Antoni A and B types of tissues histologically.2 Type A tissue is highly cellular with little extra cellular matrix while type B tissues are less cellular with more loosely arranged cells.
The T1-weighted magnetic resonance imaging (MRI) showed two isointense lesions on the cerebellopontine angle
, while T2-weighted MRI showed hyperintensity at the medial lesion (Figure 1).
Caces et al., "Contribution of endoscopy of the cerebellopontine angle
by retrosigmoid approach.
The most common location for this cyst type is at the cerebellopontine angle
(about 50%), but it also might occur in sellar and parasellar regions, diploe, rhomboid fossa, fourth ventricle/brainstem, the corpus callosum, and the pineal gland.
On MRI scan, performed 8 weeks after admission, the brain abscess located in the right cerebellopontine angle
had reached a size of 4 cln, leading to a rise of intracranial pressure that could not be controlled by intravenous administration of mannitol and dexamethasone.
Vascular origin of cerebellopontine angle
The cerebellopontine angle
(CPA) is an anatomic region that contains important neural and vascular structures such as cranial nerves, blood vessels, and parts of the central nervous system.
An enlarged left jugular foramen with a pouch was observed, extending from the left cerebellopontine angle
cistern (Figure 3).
Rotate the patient's head about 10[degrees]–20[degrees] to the contralateral side from the lateral position, to provide a direct view angle with less retraction to the cerebellar hemisphere, and can successfully open cerebellopontine angle
In a study by Galarza et al, the posterior fossa arachnoid cysts were located at the vermis-cisterna magna (n=4), the cerebellar hemispheres (n=2), the cerebellopontine angle
(n=3) and the quadrigeminal cistern (n=1).
Other rare sites include leptomeninges (oligodendrogliomatosis), cerebellopontine angle
, cerebral ventricles, retina, and optic nerve.