Radiological Spectrum of Central Nervous System Manifestations of Neurofibromatosis 2

A 21-year-old male patient from rural Bengal presented to us with insidious onset, very slowly progressive weakness of all four limbs and bilateral facial weakness. He had diminished hearing abilities since childhood. His father had similar complaints of hearing loss and walking difficulty and passed away in an RTA at 38 years of age. Neurological examination was marked by bilateral findings of lateral rectus palsy, diminished facial sensation, weakness of muscles of mastication and facial expressions, and sensory neuronal hearing loss. Muscle power was uniformly decreased in all four limbs (Medical Research Council grade 4+/5), with marked atrophy in all four limbs, more in the lower limbs and distally and neuropathic tremors. There was pan-hyporeflexia and diminished sensory perception of all modalities in all four limbs. Routine blood investigation was unrevealing. MRI Brain revealed multiple avidly enhancing extra-axial masses suggestive of vestibular and trigeminal schwannoma and meningiomas. MRI spine also showed multiple enhancing extra-axial masses and several intramedullary lesions along the cervico-medullary junction suggestive of meningiomas and ependymoma, respectively [Figure 1]. BERA showed bilateral auditory pathway dysfunction. Nerve conduction study showed an axonal sensory-motor polyneuropathy with a chronic denervation pattern on electromyography.Figure 1: MRI Brain T1 post-contrast axial sequence shows extra-axial broad-based enhancing lesions adjoining the bilateral sylvian fissure area suggestive of meningiomas (a), multiple avidly enhancing extra-axial mass of variable size in bilateral cerebellopontine angle and along the course of bilateral trigeminal nerve roots suggestive of multiple schwannomas in axial (b, c) and coronal sections (d); MRI Spine T1 post contrast sagittal (e) and axial sequence (f-h) shows multiple enhancing extra-axial masses around the cervico-medullary junction and cervical region with cord swelling and multiple intramedullary enhancing lesions suggestive of ependymomaA diagnosis of Neurofibromatosis 2 (NF 2) was made based on the presence of bilateral vestibular schwannoma and positive family history. The patient declined surgical intervention and was offered rehabilitation therapy. Vestibular schwannoma is the hallmark of NF2 and is the chief mediator of NF2-associated morbidity. Other cranial nerves to be commonly associated with schwannoma include oculomotor and trigeminal nerves. Multiple meningiomas may be seen in as many as 50% patients, commonly seen in the convexities of the skull. Spinal schwannoma and meningiomas are the most common spinal tumors, which can be seen in up to 70% of the cases of NF2. Ependymomas are intramedullary tumors, seen in 33–53% of the patients, often occurring in the cervico-medullary region. Polyneuropathy, mostly axonal, is a less described neurological manifestation in NF2 and can occur even in the absence of nerve sheath lesions.[1,2] Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.