[Time-course of interocular alignment in arteficially esotropic cats]. / A szemtengely-beállítódás idóbeli lefolyása múvi kancsal macskákban.

Strabismus induced by eye-muscle surgery is a widely accepted experimental model of discordant binocular vision. Up to now, no attention was paid to the progress of strabismus in the postsurgical period, although, the grade of the developing strabismus is strongly influenced by the loss of binocularity in the visual system. Following lateral rectus laminotomy of 2-week-old kittens, the Hirschberg method and prisms were used to assess interocular alignment. The angle of deviation was measured weekly. During the first postoperative weeks, cats fixated still alternally, while by the end of the second postnatal month, when compared to healthy controls, operated cats were unable to align their eyes parallelly. They also showed persistent esotropy (+35 +/- 7 delta) that developed with a characteristic time-course. The interocular misalignment in artificially strabismic kittens develop gradually, and does not simply appear after the operation. The nature of this pathological process resembles the normal development of eye-movements in kittens, as well as in primate infants. Therefore, the surgery for strabismus in experimental animals at the earliest time point during the sensitive period are recommended, in order to provide ample time-window window for the effective development of the "strabismic visual system".

Norrie-Warburg syndrome: two novel mutations in patients with classical clinical phenotype.

Norrie-Warburg syndrome (NWS) is a rare X-linked disorder characterized by blindness, which is invariable, deafness and mental disturbances, which are present occasionally. We describe here two novel mutations, a missense mutation (C126S) and a 1-base pair insertion (insT466/T467), together with a recurrent mutation (M1V), found in patients presenting with the classical clinical phenotype of NWS. All three mutations are likely to result in prominent structural changes of the norrin protein.

Retinoscopy after excimer laser photorefractive treatments.

Photorefractive keratectomy (PRK) is capable of changing the refractive power of the human cornea. Retinoscopy is an objective method of measuring the refractive power of the eye. The authors performed PRK in 28 myopic eyes with the Aesculap Meditec MEL 60 ArF excimer laser. During a prospective study, the subjective and objective refractive power of the eyes were assessed and compared 6 months after PRK. The average preoperative refractive error was: -5.11 +/- 2.51 D and -5.08 +/- 2.20 D on the right side (n = 16) and on the left side (n = 12), respectively. In order to obtain the best corrected visual acuity 6 months after PRK, the right and left eyes needed an average of -0.09 +/- 0.26 D and -0.33 +/- 0.64 D postoperative correction, respectively. The postoperative refractive change could be verified with the retinoscopy at +/-0.5 D accuracy. The authors describe a double refractive corneal ring after PRK, which may disturb retinoscopy. The post-PRK refractive change can be verified by retinoscopy. Postoperative funduscopy, fundus photography and possible future retinal procedures were not disturbed by the double corneal refractive rings in myopic eyes.