Figure 14-92.

Acute Polioencephalomalacia, Brain, Cerebral Hemispheres and Midbrain, Steer.

A, Compare the relative lack of gross lesions with those revealed by ultraviolet (UV) light in B. B, Bilaterally symmetric laminar pattern of apple-green autofluorescence (from mitochondrial derivatives) involving the full thickness of the cortex indicates areas of necrosis in the gray matter. Although not shown here, the colliculi were also autofluorescent. The cerebrum is exposed to 365-nm UV light from a Wood's lamp. Similar results can be obtained with fixed (preserved) brain.

(Courtesy Dr. P.N. Bochsler, School of Veterinary Medicine, University of Wisconsin-Madison.)