A 30-year-old male presented with complaints of holocranial headache with transient episodes of blurring of vision for 1 month. His neurological examination was normal. Fundoscopy revealed bilateral florid papilledema.\nHe was investigated with MRI brain, which revealed a hyperintense (T1W and T2W) solid cystic lesion measuring 3 × 2.9 × 3 cm3 in the anterior third ventricle causing hydrocephalus with enhancement on contrast imaging. The solid portion was hypointense on T2W images and was nonenhancing on T1W-Gadolinium contrast images [Figure -]. The imaging differential diagnosis was colloid cyst with inspissated protein contents or craniopharyngioma.\nThe patient underwent right frontal craniotomy, and the lesion was approached through interhemispheric transcallosal interforniceal route as the lesion was large and would have been difficult to excise from transforaminal variation of the transcallosal approach. The lesion was solid cystic located in the third ventricle near the foramen of Monro and contained about 2-3 mL of machine oil like fluid which was drained. The solid part of the lesion was avascular, firm, and grayish black in color which was excised. The capsule was removed completely except for the part which was densely adherent to the floor of the third ventricle. An Ommaya reservoir was kept in the third ventricle for external ventricular drainage []. The external drain was removed on postoperative day 5, and a CT scan was repeated on day 7 to look for the residual blood in the ventricles. There was dilatation of the ventricles with periventricular lucency for which a right ventriculo-peritoneal shunt was performed. There was no residual tumor left in the third ventricle.\nHistopathological examination of excised specimen revealed all the typical diagnostic features of a colloid cyst except for certain parts of the cyst wall where the simple, compressed, ciliated, cuboidal lining lacked a brush border and was sometimes entirely missing. Moreover, the cyst wall was multilayered and thickened by granulomatous tissue which was composed of a potpourri of cells. There was a predominance of epithelioid cells and macrophages, many of which contained refractile material and hemosiderin. Polymorphonuclear leukocytes were diffusely scattered throughout the granuloma, and lymphocytes were seen in focal collections. Foreign body giant cells were not a conspicuous feature. Cholesterol clefts were also noted [Figure -].\nThe patient is under regular follow-up and doing well with no fresh neurological deficits at end of 1 year.
A 20-year-old male patient presented to our outpatient services with complaints of neck pain for 4 months and intermittent vomiting for 2 months duration. General physical examination was unremarkable. Neurological examination revealed left upper limb weakness (power 4+/5, Medical Research Council grading). Rest of the examination was normal.\nGadolinium-enhanced magnetic resonance imaging (MRI) revealed a well-defined lobulated lesion in the ventral cervicomedullary region from medulla to upper border of C2 vertebra. The lesion was heterogeneous in appearance; the anterior part measured 2.8 × 1.6 cm and was hypointense and hyperintense on T1- and T2-weighted images, respectively; while the 1.7 × 1.1 cm sized posterior part was iso to mildly hyperintense on T1 and heterogeneously hyper intense on T2-weighted sequences [Figure and ]. The anterior part of the lesion was isointense, whereas the posterior part was hyperintense on fluid attenuation and inversion recovery (FLAIR) sequences. There was mild restriction on diffusion-weighted sequences. On post-contrast study, rim enhancement was evident in the posterior part of the lesion []. Preoperative diagnosis was neurenteric cyst. Surgery was performed in prone position. A midline suboccipital craniectomy (with bone removal more on left side), left-sided C1 posterior arch removal, and partial C2 hemilaminectomy were performed. Intraoperatively, there was a well-defined, intradural, extra-medullary encapsulated, relatively avascular, lobulated lesion containing easily suckable, cheesy material located anterior to medulla extending up to C2 vertebral level. Vertebral artery, lower cranial nerves, and posterior inferior cerebellar artery were well visualized and preserved. Tumor decompression was followed by near total excision of the cyst wall in view of adherence of the cyst wall focally to surrounding vital structures. Postoperative course was uneventful and he was discharged on 7th postoperative day and is currently on regular follow-up. At the last follow-up of 3 months, patient was well with no deficits. Postoperative MRI showed a very small residual lesion [].\nHematoxylin and eosin photomicrographs showed epithelial lining thrown into folds along with irregular bundles of collagen. Higher magnification images show a prominent columnar epithelial lining with goblet cells focally thrown into papillary formations (×100), pseudostratification, and absence of cilia (×400). Overall features were consistent with an endodermal (neurenteric) cyst of Hind-gut type [Figure and ].