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As a consequence of animal studies reduction of the light regimes have been tried on patients with retinitis pigmentosa. The trials have been very limited and have not given reason for hope that such reduced light therapy may be beneficial. However, RP patients trying red glasses have reported acute subjective improvement of their visual function. It was the purpose of this study to try to document the reports more objectively. Five visual functions were tested with and without red glasses with the following results: 1. Visual acuity and contrast sensitivity. For one volunteer a small reproducible improvement was found. 2. Color vision. In most cases deterioration was found of already deficient color vision. 3. Visual fields. For volunteers with relatively preserved vision no difference or slight deterioration was found. For the other volunteers slight improvements were found. 4. Intraocular light scatter. No differences were found. 5. Dark adaptation. Improvements were found when the glasses were used as adaptation aid according to the method of Trendelenburg (rod function). For cone function no difference was found upon continuous wearing of red glasses. In conclusion: use of red glasses does not seem to be of great benefit as a rule. On the other hand, apart from the reduction in color discrimination no serious disadvantages seem to be inherent in their wear by RP patients.

Gyrate atrophy (GA) of the choroid and retina is an extremely rare inherited chorioretinal dystrophy. Ornithine aminotransferase (OAT) gene mutations are identified in patients with GA. The purpose of this study was to report a novel deletion mutation of the OAT gene and describe clinical features of two brothers with GA in a Japanese family. We performed ophthalmic examinations, including best-corrected visual acuity, slit-lamp biomicroscopy, dilated funduscopy, fundus autofluorescence imaging, optical coherence tomography, visual field testing, and full-field electroretinography (ERG). Serum ornithine concentrations and OAT activities were analyzed. Mutation screening of the OAT gene was performed using Sanger sequencing. Both brothers had compound heterozygous mutations (p.K169DfsX10 and p.R426X), one of which was novel. Their unaffected parents carried one of the mutations heterozygously. An arginine-restricted diet was started in the younger brother at the age of 2 years, while the diet was not initiated in the older brother until the age of 6 years. After more than 15 years of follow-up, the dietary treatment seemed to slow the progression of the chorioretinal lesions in the younger brother. However, when compared at the same age, the younger brother had more reduced ERG amplitudes and constricted visual fields than his older brother. We identified a novel frameshift mutation (p.K169DfsX10) in the OAT gene. While an early arginine-restricted dietary treatment suppressed the fundus changes of GA to some degree in the younger brother, the efficacy of suppressing the progression of visual function loss could not be clearly determined.

Three separate intra-ocular pressure assessment preliminary studies utilising the Goldmann, E.M.T. 20 and the Digilab Model 30R pneumatonometer were carried out on a total of 114 eyes with glaucoma, and in 184 normal eyes in 162 patients. In general the E.M.T. 20 gave a lower result than the Goldmann but both compared well within the normal intra-ocular pressure range. Within the normal intra-ocular pressure range the pneumatonometer generally gave a 1–3 mm Hg higher reading than the Goldmann but in the glaucomatous eyes this difference became much less and readings tended to be similar with both tonometers. The fixed calibration of the E.M.T. 20 and its accuracy for pressures in the 20 mm Hg range make it an ideal instrument for screening for glaucoma but it is not suitable for the accurate stabilisation of glaucoma patients under treatment. The accuracy of the pneumatonometer in the range of intra-ocular pressure above 22 mm Hg render it the instrument of choice for the diagnosis and control of glaucoma patients. Added advantages of the pneumatonometer were the resilience of the probe to accidental damage and the ability to record the ocular pulse.

Spatial contrast sensitivity functions were evaluated in 30 patients with macular disorders and 16 age-matched control subjects. Eighteen of the affected eyes had macular holes and the rest had isolated macular problems. A loss in spatial contrast sensitivity in the central visual field indicated a relative scotoma resulting from macular dysfunctions. The nature and size of a localized scotoma such as the type caused by a macular lesion was estimated by measuring spatial contrast sensitivity as a function of retinal area centered on the fovea. Such spatial-contrast-threshold perimetry was found to be helpful in differential classification of macular holes. Spatial contrast sensitivity and visual resolution improved with increasing retinal area even in the eyes with macular holes, but never reached normal sensitivity for spatial frequencies above 5 cycles per degree (cpd) within our experimental conditions. The loss in sensitivity to low spatial frequencies (⩽ 5 cpd) was found to be apparent and a function of the retinal area stimulated. The summation curves (contrast sensitivity vs. stimulus size) were abnormal for all spatial frequencies. The ‘critical’ sizes (i.e. the stimulus size above which no increase in sensitivity occurred) were always larger in the affected eyes than those in the normal. Thus ‘critical’ areas of complete summation in the parafovea may be a better measure of functional integrity of central retina in the presence of a foveal lesion than the visual resolution that varies with the retinal area and location activated. Evaluation of contrast sensitivity of the parafoveal regions with nonfunctional fovea also indicated existence of similar mechanism of spatial vision in the fovea and the parafovea.

Purpose: To describe the results of autologous limbal transplantation in the treatment of unilateral chemical burns. Patients and methods: Two patients, a 40-year-old male (case 1) and a 35-year-old male (case 2), experienced grade III chemical trauma and were treated with autologous limbal grafting (case 1) after a postaccident period of 3 and 9 months, respectively. Change in visual acuity, epithelial healing time and postsurgical topography healing patterns were documented. Results: Snellen visual acuity improved from 0.1 to 1.0 in both cases. Epithelial healing time for cases 1 and 2 were 4 and 2 weeks, respectively. Corneal topography of case 1 showed an induced inferior steepness type of asymmetrical astigmatism in the graft area. Serial topography showed no induced astigmatism in the donor eyes. Conclusion: Autologous limbal grafting is an adequate treatment for selected cases of unilateral chemical burns and facilitates rapid improvement in visual function. Early limbal grafting in case 1 resulted in rapid re-epithelialization and prevention of complications.

The literature on nearwork-induced transient myopia (NITM) is reviewed, with NITM being defined as the short-term myopic far point shift immediately following a sustained near visual task. A majority of these investigations demonstrated the presence of NITM for a variety of test parameters, e.g., visual acuity, contrast sensitivity and far point. Overall, these studies reported relatively small myopic shifts, with a mean of approximately 0.40 D and a range from 0.12 to 1.30 D. The subsequent decay is characterized by an exponential function with a relatively short time course. While the precise etiology and implications of NITM remain unclear, speculations regarding its origin and relevance to clinical myopia are discussed. Studies that did not demonstrate NITM are also reviewed.

In order to investigate functional differences between fundus flavimaculatus and ophthalmoscopically similar diseases, we performed testing of spectral sensitivity, transient tritanopia, visual fields, fluorescein angiography, color vision, electrophysiological parameters, dark adaptation, cone flicker threshold during dark adaptation, and a thorough clinical investigation in five patients. Four had characteristic fundus flavimaculatus, while one patient turned out to have an atypical form. All five patients showed similar results in clinical investigations, electrophysiological data, and visual field tests. However psychophysical tests showed a number of differences in the single atypical patient. Although his ophthalmoscopic picture was not entirely typical of fundus flavimaculatus, only his psychophysical data could identify the patient as functionally distinct from the other four.

Using an enzyme linked immuno-assay (ELISA) and spectrophotometry, we determined levels of secretory IgA and lysozyme in tears of 69 patients with Graves' ophthalmopathy and 28 controls. The quantitative determination of secretory IgA and lysozyme in tears provided an impression of the functioning of the lacrimal gland in the two groups. An IgA/lysozyme ratio was calculated in both patients and controls as a parameter for the activity of the secretory IgA-producing plasma cells in the lacrimal gland. An increase in the IgA/ lysozyme ratio was observed in 23 patients (33%) and one control (3%). Half of the patients who had suffered from the disease for more than 5 years showed a raised IgA/lysozyme ratio. No correlation was found between the IgA/lysozyme ratio and the NOSPECS classification. Our findings suggest that the lacrimal gland is involved in the orbital condition produced by Graves' ophthalmopathy. In most cases the involvement occurs in patients with a long history of the disease.

To record electroretinograms (ERG) produced by short-wavelength-sensitive cone mechanisms (SWS-cone ERG), the authors used three kinds (blue, green, and red) of light-emitting diode (LED) which were built into a contact lens electrode assembly. The LEDs were used as both stimulus and background light sources. ERG was recorded using blue LED after 10 min of yellow light adaptation produced by green and red LEDs. Duration of photo-stimulation was either 2 or 100 ms. ERG recorded in normal human subjects showed two positive waves with 2 ms photo-stimulation. Amplitude of the former positive wave (b1-wave) was attenuated when the luminance of yellow background increased, and the latter positive wave (b2-wave) was attenuated when the color of photo-stimulation was green or red. These findings suggest that middle-wavelength-sensitive and long-wavelength-sensitive cone mechanisms generated the former positive wave (b1-wave) and SWS-cone mechanisms generated the latter positive wave (b2-wave). Ratio of b2-wave-amplitude to b1-wave-amplitude with 2 ms photo-stimulation measured on 39 normal subjects ranged from 0.5 to 2.0. It was concluded that this three-colored LED built-in electrode was useful for recording SWS-cone ERG.

Contrast sensitivity function after cataract extraction and intraocular lens implantation has been mainly correlated to the type or the material of the intraocular lens. Our purpose was to identify other possible factors, like posterior capsule, to contrast sensitivity alterations after cataract surgery, comparing patients operated for cataract by techniques that mainly differed on the posterior capsule's integrity. The intraocular lens implanted was either a posterior or an anterior chamber one, always monofocal and made of PMMA. We measured contrast sensitivity function at four spatial frequencies in two groups of operated individuals (group A and B) and in one group of healthy control individuals. Each group consisted of 42 eyes. Group A comprised eyes with intact, clear posterior capsule and posterior chamber monofocal intraocular lens. Group B comprised eyes with ruptured or removed posterior capsule and anterior chamber monofocal intraocular lens. Control group comprised healthy control eyes. A pair matched design was used to compare contrast sensitivity values among the individuals of the three groups. No statistically significant differences in contrast sensitivity values were found when group B patients were compared to healthy controls (p>0.05). Patients of group A exhibited contrast sensitivity function impairment at intermediate and high spatial frequencies when compared to patients of group B (p <0.05) and to controls (p <0.01). It seems that intact posterior capsule provides inferior visual function, in spite of relatively good visual acuity and apparently satisfactory results.