Fig. 2-3. Thirty-nine year-old with sudden onset of loss of vision in the left visual fields associated with right temporal headache. An aortic valve prosthesis had been implanted some months before and he had systemic evidence of embolization in the recent past. His deficits included the left visual field cut and the very striking spatial disorientation depicted above. He was unable to continue his prior job as an integrated circuit designer despite normal verbal intelligence. He denied the presence of a visual field deficit even when demonstrated on repeated testing.