Mastoiditis complicated with Gradenigo syndrome and a hypertrophic pachymeningitis with consequent communicating hydrocephalus.

We present the clinical, radiological and pathological features of a case of a cranial hypertrophic pachymeningitis that developed in the course of mastoiditis and petrous apex inflammation and responded to immunosuppressive therapy only. Documented by the development of clinical findings, magnetic resonance imaging, cerebrospinal fluid changes, histopathology findings, by otosurgical intervention and finally by the insertion of a ventriculo-peritoneal shunt, the case illustrates a gradual development of pachymeningitis with consequent hydrocephalus and intracranial hypertension. We consider this disease development an example of immune-induced proliferative fibrotic changes in meninges.