Hydranencephaly (HE) is a rare congenital anomaly in which there is a complete or near complete absence of bilateral cerebral hemispheres which are replaced by a membranous sac filled with Cerebrospinal Fluid (CSF). Thalami, brainstem, and cerebellar hemisphere are preserved. A small island of cerebral parenchyma may also be seen along the inner aspect of the calvarium. Several theories regarding its aetiopathogenesis have been postulated with the hypothesis of bilateral occlusion of supraclinoid segment of Internal Carotid Artery (ICA) being widely accepted. The authors present a case of a two-month-old male child presenting with increasing head size since birth, associated hydrocephalus and residual parenchymal sleeve visualised on neurosonogram and calcifications depicted on computed tomography. The diagnosis of Cytomegalovirus (CMV) was confirmed serologically and further neurosurgical consultation was advised for increasing head size secondary to hydrocephalus. The HE is usually detected in the second trimester, however can also occur in early or later gestation and has a very poor prognosis.

Background Tubercular infection of the brain and spine is relatively common in endemic regions of the world. Central nervous system tuberculosis can have varied manifestations. The familiar imaging findings are hydrocephalus, ring-enhancing tuberculomas, and meningeal enhancement, having a preference for basal regions. Myelitis is the most common imaging manifestation of spine, with holocord involvement being a rare presentation, as seen in our case. Case presentation We present a case of a pediatric patient undergoing treatment for a tubercular infection of the brain. The patient developed acute onset quadriparesis, manifesting as holocord transverse myelitis on imaging. The imaging findings in the brain manifested as basal meningeal enhancement and non-communicating hydrocephalus, managed by shunt placement. As of the latest, the patient is on follow-up and has a stable disease course. Clinical and laboratory investigations excluded other infectious and non-infectious causes of transverse myelitis, including neuromyelitis optica spectrum disorders. Conclusions Longitudinally extensive transverse myelitis is a rare complication of tubercular myelitis seen as a long-segment signal abnormality with swelling of the cord and corresponding post-contrast enhancement. Involvement of the entire cord is rare, with a handful of cases reported in the literature.