Presentation
Headache.
Patient Data
There's a large heterogeneous space occupying lesion at the left cerebellar hemisphere and the left side of the vermis superiorly, distorting the left middle cerebellar peduncle. It compresses and attenuates the 4th ventricle with consequent moderate dilatation of the supra-tentorial ventricular system and periventricular CSF permeation. It exerts positive mass effect in the form of anterior displacement of the pons and medulla with obliteration of the the pre-pontine cistern , and inferior cerebellar tonsillar herniation through the foramen magnum with consequent upper cervical cord syrnix. The lesion has a striking striated appearance on T2 WI. On DWI, the lesion shows high signal intensity. Corresponding ADC map shows no restricted diffusion. No significant post contrast enhancement.
Radiological findings are suggestive of left cerebellar Lhermitte-Duclos disease.
Histopathology after excision revealed L hermitte-Duclos disease WHO grade 1.
Case Discussion
This is a pathologically proven case of Lhermitte-Duclos disease which shows typical radiological features of the disease which include the striated/tigroid appearance on T2 with lack of contrast enhancement, though an outsider perspective on the presented case highlights its unusual diffusion-weighted imaging (DWI) signal characteristics, where the signal is unexpectedly high on DWI with no corresponding low signal on the ADC map (it appears isointense to the normal cerebellum).
Lesions in Lhermitte-Duclos usually elicit isointense signal on DWI similar to adjacent normal cortex. Though, It has been reported that those lesions might elicit high signal on diffusion-weighted images with no corresponding low signal on ADC images attributable to T2 shine through effect 1.
Another report showed lesions of true diffusion restriction with high signal on DWI and low ADC values (decreased relative to normal cerebellar tissue) 2 , they suggested that would be likely secondary to hypercellularity with replacement of the granular and pukinji cell layer with ganglion cell and dense collection of axons 2.
Unable to process the form. Check for errors and try again.