Matsuo, Toshihiko

We report herein the disappearance of macular hard exudates after the introduction of hemodialysis in diabetic patients. A 62-year-old woman and a 52-year-old man with diabetes mellitus showed hard exudates in the macula of the left eyes. Both patients had previously undergone panretinal photocoagulation in both eyes. During the follow-up, hemodialysis was introduced for deteriorating chronic renal failure caused by diabetic nephropathy. Half a year later, macular hard exudates in the left eyes disappeared dramatically in both patients, but the visual acuity remained the same. No additional laser treatment was done during the observation period. Hemodialysis is considered to have accelerated the resolution of macular hard exudates in both patients. The deposition of macular hard exudates in diabetic patients is due in part to concurrent poor renal function.

To study the expression of the amiloride-sensitive sodium channel, a putative mechano-receptor in the rat eye, reverse transcriptase-polymerase chain reaction and in situ hybridization were done. The gene for the alpha subunit of the amiloride-sensitive sodium channel was shown by polymerase chain reaction to be expressed in mRNA isolated from the whole eye tissue. In situ hybridization demonstrated that the gene was expressed in basal layers of the corneal and conjunctival epithelium, ciliary epithelial cells, lens epithelial cells at the equator, retinal and iris pigment epithelial cells, ganglion cells and cells in the inner and outer nuclear layers of the retina. The results suggest that the amiloride-sensitive sodium channel plays a role in maintaining sodium balance as well as in possible mechanosensation in these ocular tissues.

The purpose of this study was to search for chromosomal susceptibility loci for comitant strabismus. Genomic DNA was isolated from 10mL blood taken from each member of 30 nuclear families in which 2 or more siblings are affected by either esotropia or exotropia. A genome-wide search was performed with amplification by polymerase chain reaction of 400 markers in microsatellite regions with approximately 10 cM resolution. For each locus, non-parametric affected sib-pair analysis and non-parametric linkage analysis for multiple pedigrees (Genehunter software, http://linkage.rockefeller.edu/soft/) were used to calculate multipoint lod scores and non-parametric linkage (NPL) scores, respectively. In sib-pair analysis, lod scores showed basically flat lines with several peaks of 0.25 on all chromosomes. In non-parametric linkage analysis for multiple pedigrees, NPL scores showed one peak as high as 1.34 on chromosomes 1, 2, 4, 7, 10, 15, and 16, while 2 such peaks were found on chromosomes 3, 9, 11, 12, 18, and 20. Non-parametric linkage analysis for multiple pedigrees of 30 families with comitant strabismus suggested a number of chromosomal susceptibility loci. Our ongoing study involving a larger number of families will refine the accuracy of statistical analysis to pinpoint susceptibility loci for comitant strabismus.</P>

The vision-screening program for 3.5-year-old children in Japan consists of 3 steps:questionnaires and home visual acuity testing, visual acuity testing by nurses and inspection by medical officers at regional Public Health Centers, and examinations by ophthalmologists. In this study, we tested refraction with a hand-held autorefractometer in addition to visual acuity testing and inspection to reveal whether or not autorefraction leads to better detection of eye problems. Autorefraction was performed in 6 consecutive sessions by a single examiner in 265 children at 3.5 years of age who all visited the same center. The children were sent to the third step of examinations by ophthalmologists based on refractive error criteria:3 diopters myopia or 1 diopter hyperopia, and/or 2 diopters astigmatism in either eye, in addition to the current criteria:1) failure in either eye for 0.5 visual acuity at the center, 2) eye-related symptoms revealed by the questionnaires, or 3) eye problems detected by medical officers. Notices to visit ophthalmologists were issued for 64 children (24%), and 37 of those (58%) made the visits, so that documents containing final diagnoses were sent back to the Public Health Office. Of the 64 children, 12 were sent to ophthalmologists based on the current criteria only, 10 based on both the current criteria and the refractive error criteria, and 42 based on the refractive error criteria only. Twelve of the 13 children visiting ophthalmologists by the current criteria had diagnoses such as amblyopia and strabismus. In contrast, 15 of 24 children visiting ophthalmologists by only the refractive error criteria had mainly diagnoses of refractive errors, with no serious problems. In conclusion, autorefraction in addition to visual acuity testing and inspection led to detection of only one additional case of an eye disease at 3.5 years, while tripling the number of children sending to the third-step examination by an ophthalmologist. Thus, from a cost-effectiveness standpoint, autorefraction is not recommended as an additional test when the current system is conducted as designed.