Tuesday, November 15, 2016

MOC Exam Topic: Status Marmoratus

The neurons of the infant caudate, putamen, thalamus, and globus pallidus are susceptible to damage by hypoxia-ischemia. In some extensive injuries, a marked gliosis occurs and, if the brain is actively forming myelin in that region, there is hypermyelination of the area with aberrant myelination of astrocytic processes. There is frequently also neuronal loss and mineralization of residual neurons. The resulting white, firm, marbled-appearing lesion is called status mamoratus. Thought to occur if a hypoxic insult happens before the age of 6 to 9 months, status marmoratus has been associated with complicated parturitions and acute febrile illness during the first year of life. Lesions in the basal ganglia occurring after the period of active myelination exhibit only gliosis associated with neuronal loss. (Source: Greenfield's Neuropathology, 8th Edition)

status marmoratus involving thalamus and basal ganglia


Marc Del Bigio said...

Careful evaluation by Friede & Schachenmayr (Early stages of status marmoratus. Acta Neuropathol;38: 123-127, 1977) of these areas showed that the marbled pattern is simply abnormal orientation of myelinated axons within scarred structures, not the aberrant myelination of astrocytic processes claimed by earlier authors.

Brian E. Moore, MD, MEd said...

Thanks for that clarification, Marc!