Restricted diffusion in the corpus callosum: A neuroradiological marker in hypoxic-ischemic encephalopathy

Background:

Restricted diffusion within the splenium of the corpus callosum has been described by other authors in various conditions, however, restricted diffusion in the entire corpus callosum or isolated involvement of the splenium, genu, or body has been infrequently reported on magnetic resonance imaging (MRI) in neonatal hypoxic–ischemic encephalopathy. We report a series of cases showing different patterns of involvement.

Methods and Materials:

Perinatal imaging with MRI including diffusion-weighted imaging was performed in 40 neonates with hypoxic–ischemic encephalopathy, including 11 premature neonates. Sixteen out of 40 patients demonstrated restricted diffusion within the corpus callosum. Out of 16 patients, 9 showed restricted diffusion in the entire corpus callosum, 4 had isolated splenium involvement, 2 had body and splenium signal abnormality, and 1 showed diffusion restriction only in the genu.

Conclusions:

Changes in the corpus callosum were also associated with more severe clinical presentation of encephalopathy. Restricted diffusion within the corpus callosum in infants with hypoxic–ischemic encephalopathy is often associated with extensive brain injury and appears to be an early neuroradiologic marker of adverse neurologic outcome.

Unusual presentation of hydatid cyst - ruptured intraventricular hydatid

Echinococcosis in humans occurs as a result of infection by the larval stages of taenid cestodes of the genus Echinococcus. Most of the intracranial hydatids develop in brain parenchyma. Hydatid cyst within the cerebral ventricle is quite unusual. Literature review showed few case reports of childhood as well as adult intraventricular hydatid cysts. None of these cases presented for the first time with features of ruptured intraventricular cyst. This is a very rare presentation of a common disease. The possibility of infestation with E. granulosus should be included in the differential diagnosis of raised intracranial tension in patients reporting from endemic areas, because the prognosis following surgical intervention is excellent, especially in the pediatric age group.

The many faces of cysticercosis

Cysticercosis in humans results from infestation with the larval stage of the parasite Cysticercus cellulosae of the tapeworm Taenia solium. Man normally acts as a definitive host. However, man can occasionally be the intermediate host, when cysticercosis becomes clinically manifest. Larvae lodge in the target organs, the brain, eyes, spine and skeletal muscles, where their appearances are highly suggestive or specific. We present a spectrum of such images, as encountered in Western India.

Superficial siderosis of the nervous system

A male patient had been operated in 1990 at a different hospital for a suprasellar mass lesion causing progressive blindness. At exploration, the mass was felt to be inflammatory in nature with arachnoiditis and hydrocephalus. Deep yellow staining of tissues round the mass was recorded at the time of first surgery. The patient was readmitted in 1996 for progressive visual failure, ataxia, mental changes and deafness. MRI confirmed persistence of suprasellar mass and showed the characteristic findings of superficial siderosis of CNS. On reexploration, the mass had multiple vessels over the walls and contained xanthochromic fluid. It was excised and histologically examined to be an epidermoid with a cyst. The patient developed chest infection, became drowsy and died. The MRI picture, the CSF finding and the yellow staining of tissue confirmed the diagnosis of superficial siderosis of the CNS, which was first thought of after seeing the diagnostic MRI. The cause of the superficial siderosis was recurrent bleeding from the tumour.