Optic neuropathy secondary to cat scratch disease: case report.

Optic neuropathy due to cat scratch disease is a relatively infrequent occurrence associated with macular star formation and is characterized by sudden painless loss of vision mostly unilateral. Bartonella henselae is well recognized as the etiologic agent in cat scratch disease. Ocular complications of the disease occur in up to 10% of patients and include neuroretinitis.

'Cherry red spot' in a patient with Tay-Sachs disease: case report.

Tay-Sachs disease is an autosomal recessive disorder of sphingolipid metabolism, caused by enzyme hexosaminidase A deficiency that leads to an accumulation of GM2 in neurocytes which results in progressive loss of neurological function. The accumulation of lipid in retinal ganglion cells that leads to a chalk-white appearance of the fundus called 'cherry red spot' is the hallmark of Tay-Sachs disease. It is also seen in others neurometabolic diseases as well as in central retinal artery occlusion.