Cystic trochlear nerve schwannoma. Case report.
BACKGROUND
Twenty-six cases of pathologically verified schwannomas of the trochlear nerve have been reported in the literature. Five of them had a large cystic component and a smaller solid portion. Complex skull base approaches have been usually applied for their removal.


METHODS
We report on a rare case of cystic trochlear schwannoma in a 52-year-old female patient. The patient presented with double vision, facial palsy, decreased hearing, hemiparesis on the right side, and severe gait instability. Magnetic resonance imaging revealed a 2.5-cm left-sided extra-axial lesion compressing the brain stem at the lower midbrain and upper pontine level. Total resection was performed via a retrosigmoid craniotomy. After the surgery, the neurological deficit diminished considerably. At 28 months follow-up, her only complaint was mild double vision when walking down the stairs and hypesthesia in the right half of her face.


CONCLUSIONS
This case represents a rare pontomesencephalic lesion removed successfully via the simple retrosigmoid route.
Gerganov
Venelin
V
International Neuroscience Institute- Hannover, Otto von Guericke University- Magdeburg, Hannover 30625, Germany. vgerganov@gmail.com
Amir
Samii
S
Koerbel
Andrei
A
Brandes
Almuth
A
Stan
Alex
A
Madjid
Samii
S
D003390:Cranial Nerve Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008875:Middle Aged; D009442:Neurilemmoma / Q000473:pathology* / Q000601:surgery; D020432:Trochlear Nerve Diseases / Q000473:pathology* / Q000601:surgery