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 lady presented with a 6 months history of progressive headache and memory disturbances. Few days prior to presentation, she had three episodes of generalized tonic clonic seizures. She also had gait disturbances and severe giddiness. Higher mental function examination revealed impaired recent memory. Fundoscopic examination showed bilateral papilloedema. Cranial nerve examination, motor and sensory examination was normal. Plantar reflexes were extensor on both sides and Romberg's sign was positive. Computed tomography (CT) scan of the brain showed isodense lesion located at foramen of Monro with hyperdense areas suggestive of hemorrhage with foraminal obstruction. The lesion was not enhancing on contrast []. Magnetic resonance imaging (MRI) brain revealed obstructive hydrocephalus due to a large lesion in the third ventricle which was homogenously hyperintense on T1-weighted images and homogenously hypointense on T2-weighted images [].\nRight lateral ventricle was entered via right frontoparietal craniotomy and an interhemispheric transcallosal approach. A grayish red, well-defined, soft to firm lesion was reached through the interforniceal approach. Needle aspiration was attempted but was unsuccessful. The surface of the cyst was vascular, so it was coagulated. The cyst wall was thickened and its separation from surrounding tissue was difficult. On opening the cyst, there was no colloid material, but a brownish yellow organized clot was found which was removed piecemeal. The clot was easily separated from the inner cyst wall. After almost complete evacuation of cyst content, the thick wall was held with biopsy forceps with one hand and with the other hand it was dissected from the surrounding parenchymal tissue. A complete excision of the cyst was ensured. Both internal cerebral veins were seen and found intact. Pathological examination confirmed hemorrhage within the colloid cyst. Microscopic examination also showed blood clots containing hemosiderin laden macrophages and many rhomboid cholesterol crystals and chronic inflammatory cells []. Post-operatively she had no seizures. Her memory function completely improved over a 3 week period.