Magnetic resonance imaging of the cerebello-pontine angle

Abstract

A variety of extra-axial lesions occurring at the cerebello-pontine angle was examined by magnetic resonance imaging (MRI). Differences in spin sequence characteristics were found between neurilemmomas and meningiomas, with neurilemmomas exhibiting a greater increase in T2 than meningiomas. The T1 images were of less value in differentiating between neurilemmomas and meningiomas but were of value in the diagnosis of vascular lesions, due to the decreased T1 of blood clot. The T1 images were also of value in the assessment of tumour size and in the diagnosis of an epidermoid cyst. Extension of tumour into the internal auditory meatus was seen on MRI with acoustic neuromas and with one other lesion. The transverse perspective was of greatest value in lesion assessment. The coronal perspective was useful in certain situations but the sagittal perspective was of minimal clinical value.

A giant epidermoid cyst demonstrated by magnetic resonance imaging

“…The dense fibrous membranous tissues and calcification show low signal intensity on both T1‐and T2‐weighted images 2 . These MR features mimic those observed in epidermoid cysts of the intracranial and urogenital regions 1–4 …”

Knochenneubildungen in einer seltenen Raumforderung des inneren Gehörgangs

“…Die Signalintensität bei den T1-gewichteten Aufnahmen ohne Kontrastmittel variiert in der Literatur von hyper- [5,15,27,29,31,33] über iso- [8,19,24,34] bis hypointens [13], was von einigen Autoren auf den unterschiedlichen Gehalt an Kalzifizierung oder Hämosiderin [13,14,27] zurückgeführt wird. Die Signalintensität bei den T1-gewichteten Aufnahmen ohne Kontrastmittel variiert in der Literatur von hyper- [5,15,27,29,31,33] über iso- [8,19,24,34] bis hypointens [13], was von einigen Autoren auf den unterschiedlichen Gehalt an Kalzifizierung oder Hämosiderin [13,14,27] zurückgeführt wird.…”