Idiopathic Hypertrophic Pachymeningitis – MRI Diagnosis and Follow up

Idiopathic hypertrophic pachymeningitis is a rare entity, posing challenge to the radiologist for a confident prospective diagnosis. The same is of prime importance as in the absence of a definitive treatment, the clinician has to initiate a presumptive therapy based on radiological diagnosis, histopathology not being the pragmatic option in most cases. We present a case which is interesting not only by virtue of the rarity of this disease but also due to the extent of cranial nerves involved and the drastic response to therapy initiated once suspected on MRI. The emphasize of this report is on being mindful of the possibility and early recognition of signs differentiating it from other close and commoner mimickers.