Metabolic disorders of the brain: part II.

Metabolic disorders of the brain are extensive and to encompass these disorders in two articles is impossible. The aim of this article to provide a brief overview of the non-organelle based metabolic disorders affecting the brain. Due to its complexity, classification of the metabolic disorders of brain is not easy. In this article we have discussed the non-organelle based metabolic disorders under following headings: aminoaciduria, organic academia, nuclear DNA repair defects, a defect in the gene encoding myelin proteins and various miscellaneous defects. Even though the neuroimaging findings overlay and may be non-specific for many of the metabolic disorders, some of the imaging features enable the radiologist to provide the physician with a logical approach by providing a road map and/or limiting the differential diagnosis. Understanding the basic biochemical defects is important to recognize these disorders. The relevant biochemistry and genetic defects are also discussed.

Ruptured, weighted, enteral feeding-tube tip presenting as enteric foreign objects.

We present a patient who, upon radiographic examination, was found to have eight metallic-density foreign objects throughout her colon that were identified as pieces of the enteral feeding tube's weighted tip, which was no longer intact. Although this complication is rare, correct identification is important so that the defective feeding tube can be removed and replaced and so that the patient and clinician can be reassured that the metallic foreign objects present minimal risk of complications.

Tethered cord, corpus callosum abnormalities, and periventricular cysts in Wolf-Hirschhorn syndrome. Report of two cases and review of the literature.

Wolf-Hirschhorn syndrome (4p-) is a rare disorder with characteristic physical findings. Neuroimaging findings are relatively scarce. We performed a literature search and found 22 reports of neuroimaging findings. We present findings in our two cases, each with the previously unreported finding of a tethered cord. The most common abnormalities were of the corpus callosum, occurring in 71% of all cases. There appears to be a high association in the syndrome between corpus callosal abnormalities and periventricular cysts formation in the first year of life. These cysts eventually fuse with the frontal horns during late infancy with enlargement of the frontal horns. Absence of other causes for periventricular cyst formation, such as perinatal distress, prematurity, or cytomegalovirus infection, appears to strengthen the association. With further studies, neuroimaging findings may eventually assist in the diagnosis of patients with Wolf-Hirschhorn syndrome.

Intracardiac migration of a distal shunt catheter: an unusual complication of ventricular shunts. Report of 2 cases.

Unusual complications of peritoneal shunts are a well-known occurrence. The authors present 2 cases of intracardiac migration of a distal shunt catheter, summarizing the diagnosis and management of each case. This complication seems to be a rare occurrence; the transgression of the jugular vein leading to intracardiac migration of a shunt catheter has been reported only 6 times previously. The authors highlight the importance of careful and proper placement of the distal peritoneal catheter during the tunneling process, in particular avoiding too deep a penetration of the shunt passer into the neck tissues and too medial a shunt passage near the sternal notch to avoid vascular structures.