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 ].
A 77-year-old white woman presented to the emergency room with complaints of headaches, memory loss, and abnormal gait for the past 4 months. She had a 10-year history of a controlled type 2 diabetes mellitus and hypertension. At neurological examination, she was awake, partially oriented, with pupils equal round and reactive to light, without papilledema, perceived strength, eumetric intention tremor, no frontal release signs, and ataxia of gait.\nA magnetic resonance imaging (MRI) revealed a hyperintense T1WI solid cystic lesion measuring 3.0 cm×2.8 cm×2.9 cm located inside the anterior portion of the third ventricle causing obstructive hydrocephalus. The posterior portion of the lesion was predominantly solid and hypointense on T2WI and on gradient echo (GRE) T2WI, and the anterior portion was predominantly cystic with both hyper- and hypointense areas on T1WI and T2WI, with no suppression on fluid- attenuated inversion recovery (FLAIR) and no restriction to diffusion. The solid portion was hypointense on T1WI and demonstrated heterogeneous areas of enhancement after gadolinium contrast agent administration; there were also some peripheral sparse areas of enhancement in the cystic portion of the lesion. These heterogeneous peripheral enhancements and hypointensity on GRE TW2I are consistent with either hemosiderin or calcifications, raising concern for an atypical colloid cyst or a cystic craniopharyngioma [].\nA left frontal craniotomy with pterional approach and a transfrontal route using endoscopic visualization and stereotactic guidance were performed, and the intraventricular lesion was removed microsurgically. The solid part of the lesion was excised, and most of the capsules were removed except for the part densely adherent to the floor of the third ventricle. About 3–4 ml of “machine-like oil” fluid was also drained.\nIn the intraoperative view, the lesion was solid cystic located in the third ventricle near the foramen of Monro. The specimen received and fixed in 10% buffered formalin, displayed a nodular appearance, measured 2.5 cm×2.0 cm×2.0 cm, and weighed 7.0 g. It was surrounded by a delicate irregular membrane, with a yellowish color and friable areas. The solid part was firm, grayish-black in color, and avascular [].\nIn the intraoperative histological examination, a diagnosis of craniopharyngioma was made, but the definitive histopathological examination of the excised specimen revealed a colloid cyst lined by a single layer of cuboidal, partially flattened nonciliated and ciliated epithelial cells. There was a high prevalence of macrophages and epithelioid cells, many of which included refractile material and hemosiderin. In addition, cholesterol clefts and lymphocytes were seen in focal sets. Polymorphonuclear leukocytes were diffusely spread out throughout the granuloma []. The final diagnosis of a xanthogranulomatous colloid cyst with hemosiderosis was made. The immediate post-operative MRI demonstrated an almost complete reduction of the cystic lesion, with some sparse areas of contrast agent enhancement, and normalization in the lateral ventricle size []. Clinically, the patient evolved with the gradual improvement of the condition; she was discharged and followed-up conservatively with serial neuroimaging.