A 28-year-old lady presented with headache and vomiting since 11/2 years. She complained of difficulty in gripping objects with left upper limb, gait unsteadiness with tendency to sway to the left side, dysarthria and nasal regurgitation on swallowing fluids. On examination, bilateral gaze evoked downbeat nystagmus was present. Gag reflex was sluggish bilaterally but uvula was central. There was drooping of right shoulder and weakness of right sternocleidomastoid. Left cerebellar signs were present with ataxic gait. Bulk and tone of muscles was normal.\nCT [] showed a hyperdense extraxial lesion in left side posterior fossa, compressing brainstem and distorting the 4th ventricle with obstructive hydrocephalus. On MRI [], it appeared iso- to mildly hypointense on T2 weighted images and hyperintense on T1 weighted images without suppression of signal on fat saturated images. The lesion measured 5.4 × 4.2 × 5.34 cms. There was no obvious enhancement on administration of contrast. There was no restriction diffusion. On the anterior aspect of the lesion, just to the left of midline, there was a T1- and T2 hypointense focus that corresponded with slightly increased density on plain CT and showed blooming on SWI (likely calcification). The lesion showed facilitated diffusion. MRS showed a large NAA like peak at 2.02 ppm.\nShe underwent midline suboccipital craniectomy and near total excision of the lesion. Histopathology showed a cyst wall composed of pseudostratified ciliated columnar epithelium (black arrow) with extensive areas of squamous metaplasia suggestive of neuroenteric cyst.
32-year-old lady presented with complaints of oligomenorrhoea since 9 years; tremor of both hands since 9 months; intermittent right frontal headache, drop attacks, urinary incontinence, somnolence and irrelevant laughing since 6 months. On examination, there was bilateral secondary optic atrophy. No other cranial nerve involvement. Power was grade 3/5 in both upper limbs and grade 4+/5 in both lower limbs. Deep tendon reflexes were brisk. Bilateral cerebellar signs were present.\nMRI [] showed a suprasellar lesion elevating the floor of the fourth ventricle and extending into the interpeduncular fossa posteriorly. It appeared iso- to mildly hyperintense on T1 weighted images and hyperintense on T2 weighted images. There was facilitated diffusion in the lesion with high ADC values. There was no blooming on gradient echo images. There was no obvious enhancement on administration of contrast. On MR spectroscopy, there was a prominent peak at 2.02 ppm corresponding to NAA like compound. The third and lateral ventricles were dilated with periventricular hyperintensities suggestive of transependymal seepage of CSF.\nThe patient underwent right frontotemporal craniotomy, single peice orbitozygomatic osteotomy and subtotal excision of the lesion. Histopathology showed ciliated columnar, pseudostratified columnar, stratified squamous, mucosal glands, clusters of Rosenthal fibres suggestive of neuroepithelial cyst. Based on the immunohistochemical properties, a final diagnosis of neuroenteric cyst was made.