ABSTRACT
METHODS: Perceptual visual filling in at the corresponding area of toxoplasmic retinochoroiditis scotomas in the fellow eye was studied in 14 patients. Targets were programmed to appear inside the scotoma corresponding area in the fellow eye, and at two control points. RESULTS: The results showed faster perceptual filling-in latencies (p<0.0001) in the scotoma corresponding area than at the control points. CONCLUSIONS: Perceptual filling in is facilitated at the corresponding area of retinal scotomas. The neural mechanisms of this visual facilitation might be similar to those found following somatosensory cortex partial deafferentation.
Subject(s)
Adaptation, Physiological/physiology , Choroiditis/physiopathology , Retinitis/physiopathology , Scotoma/physiopathology , Toxoplasmosis, Ocular/physiopathology , Adolescent , Adult , Aged , Animals , Female , Humans , Male , Middle Aged , Pattern Recognition, Visual/physiology , Photic Stimulation/methods , Visual Cortex/physiology , Visual Fields/physiology , Visual Perception/physiologyABSTRACT
BACKGROUND: Iridocorneal endothelial syndrome is characterized by the proliferation and spreading of an abnormal corneal endothelial membrane across the iridocorneal angle and iris surface, resulting in iridocorneal adhesions, glaucoma, pupillary distortion, varying degrees of iris atrophy, and occasionally corneal decomposition with edema. These changes may possibly affect the long-term prognosis of penetrating keratoplasty in an adverse fashion. METHODS: We reviewed the clinical course of 12 consecutive eyes (12 patients) which underwent penetrating keratoplasty for corneal edema associated with the iridocorneal endothelial syndrome (mean postoperative follow up = 30 months). RESULTS: The grafts remained clear in 10 patients (83%) and the visual acuity was 20/40 or better in nine patients (75%). The endothelial cell losses averaged 13% at 6 months and 17% at 1 year after surgery. Simultaneous extracapsular cataract extraction and posterior chamber lens implantation at the time of keratoplasty posed no measurable compromise to the overall postoperative prognosis. Causes of poor visual acuity after surgery included glaucoma and graft failure (immune and nonimmune). CONCLUSIONS: The prognosis of penetrating keratoplasty in the iridocorneal endothelial syndrome appears to be very favorable in the majority of eyes.
