Causes of uveitis in the general practice of ophthalmology. UCLA Community-Based Uveitis Study Group.

PURPOSE: Most uveitis case series have come from tertiary care centers, and the relative frequencies of disorders they report may reflect referral bias. We sought information about the types of uveitis encountered in the general practice of ophthalmology. METHODS: We prospectively examined 213 consecutive cases of general uveitis, defined as intraocular inflammation other than cytomegalovirus retinopathy, seen by a group of community-based comprehensive ophthalmologists. This group of cases was compared with 213 consecutive cases of general uveitis examined by a uveitis specialist at a university referral center in the same community. All cases were categorized by anatomic site of inflammation and disease course, and, if possible, they were assigned a specific diagnosis. Cases of cytomegalovirus retinopathy and masquerade syndrome seen during the same intervals were recorded separately. RESULTS: The distribution of general uveitis cases by anatomic site of disease was significantly different between the community-based practices (anterior, 90.6%; intermediate, 1.4%; posterior 4.7%; panuveitis, 1.4%) and the university referral practice (anterior, 60.6%; intermediate, 12.2%; posterior, 14.6%; panuveitis, 9.4%; P < .00005). A cause or clinical syndrome could be assigned to 47.4% of cases in the community-based practices, and to 57.8% of cases in the university referral practice (P = .03). HLA-B27-associated anterior uveitis, cytomegalovirus retinopathy, and toxoplasmic retinochoroiditis were among the five most common forms of uveitis in both practice settings. CONCLUSION: The relative frequencies with which various forms of uveitis are seen in a tertiary referral center do not necessarily reflect the experience of ophthalmologists from the community in which the center is located. Anterior uveitis and disorders of sudden onset constitute a greater proportion of cases seen by community-based comprehensive ophthalmologists.

Screening for mouse retinal degenerations. I. Correlation of indirect ophthalmoscopy, electroretinograms, and histology.

Mice with hereditary retinal degeneration have provided excellent models for human disease of the biochemical and physiological events occurring in retinal degeneration. Since a number of mouse models are available for other human conditions, more mouse retinal degenerations would be expected to be known; however, finding new models has proved difficult since the search has usually involved laborious histologic screening. We applied the clinical technique of indirect ophthalmoscopy to screen mice for retinal degeneration and then used electroretinography and histology to determine whether true retinal degeneration was present. A Dawson-Trick-Litzkow microfiber corneal electrode was used to record the electroretinogram since the fiber does not occlude the pupil in these small eyes. Normal control values were developed. As an example of the success of the technique, one strain, lethal spot (ls) on indirect ophthalmoscopy appeared to have a retinal degeneration, but these mice had a normal electroretinogram indicating a primary optic atrophy. Likewise, one ls heterozygote that was tested as a control animal and was not suspected of having a retinal degeneration had an abnormal electroretinogram and peripheral retinal degeneration.

Screening for mouse retinal degenerations. II. Molossinus MOLC and MOLD strains.

Using screening techniques of indirect ophthalmoscopy, electroretinography, and histology, we found inbred strains of Mus musculus molossinus to have a variable onset of retinal degeneration, which may present with early loss of outer segments and photoreceptor nuclei. The early affected mice have constricted vessels, optic atrophy, and markedly abnormal electroretinograms. An intermediate form of retinal degeneration was identified with slight arterial narrowing on ophthalmoscopy and electroretinogram amplitudes approximately 50% of normal. From this preliminary study the hereditary pattern is unclear. The mice with early onset of retinal degeneration share features seen in rd mice, but in a number of the molossinus the degeneration is slower with only a partial loss on electroretinogram amplitude.

Computer analysis of Farnsworth-Munsell 100-hue test.

Color vision abnormalities indicated by the Farnsworth-Munsell 100-hue Color Vision Tests (FM-100) were analyzed by computer to better characterize and group congenital and acquired color vision disorders and to help establish statistically significant diagnostic criteria. Standard evaluation of the FM-100 is by axis and error score calculations. A method has been established for computer-averaging many tests from patients with the same color abnormalities determined by history, standard FM-100 and Nagel anomaloscope. The computer calculated an average error score and standard deviation for each of the 85 color caps. Every time a new patient was evaluated for color vision abnormality, his score was compared with averaged tests with common diagnoses, by calculating distance scores. The averaged test with the lowest distance score consistently tended to coincide with the diagnosis. An analysis of 130 FM-100 color tests found technician-calculated error scores to be incorrect, although usually minor, in 40% of the tests. The computer-calculated axes agreed well with the technician's estimates. The distance scores predicted the diagnosis accurately 89% of the time. Many errors were due to the small number of protanopes averaged and inability to distinguish trichromats from dichromats.