Hiroshi Sakaue

A 3-Year Follow-Up Study of Ocular Hypertension by Pattern Electroretinogram

A 3-year following-up study of the pattern electroretinogram (PERG) was performed in 15 eyes of 8 ocular hypertensive (OHT) patients. At first PERG recording, the amplitude of the first positive wave P1 was statistically significantly reduced in the OHT patients compared with age-matched controls (p < 0.05). There was no difference in the amplitude of the second negative wave N2 (p > 0.05). At 40 months, the amplitude of both P1 and N2 decreased and the latency of P1 was elongated. Among the changes, the decrease in N2 amplitude was the most drastic (p = 0.0001 compared with the control, p < 0.05, compared with the first recording). Glaucomatous visual field defects developed 5 years after the first PERG recording and 2 years after the reduction in N2 amplitude in 1 patient. Decreased N2 amplitude of the PERG may be an important warning sign predicting the development of glaucoma in OHT patients.

Multicenter genetic study of retinitis pigmentosa in Japan: I. Genetic heterogeneity in typical retinitis pigmentosa☆

A nationwide, multicenter study of typical retinitis pigmentosa (RP) was carried out in collaboration with 18 hospitals throughout Japan to obtain current information for genetic counseling. We analyzed the genetic heterogeneity of RP based on the parental consanguinity of 434 probands registered during a 6-month period in 1990. A gradual decline in the frequency of consanguineous marriage was recognized among the normal parents of RP patients. The relative frequencies of inheritance patterns were estimated as: autosomal recessive, 25.2%; autosomal dominant, 16.9%; X-linked, 1.6%; and simplex, 56.3%. A comparison of these results with previous reports in Japan revealed a decline in the relative frequency of autosomal recessive cases and an increase in simplex cases. This suggests a decrease in the incidence of autosomal recessive retinitis pigmentosa in Japan, as well as the necessity for exhaustive investigations aimed at identifying inheritance patterns for RP patients seeking genetic counseling.

Multicenter genetic study of retinitis pigmentosa in Japan: II. Prevalence of autosomal recessive retinitis pigmentosa

Retinitis pigmentosa (RP) is a group of genetically heterogeneous diseases with autosomal recessive (AR), autosomal dominant, and X-linked modes of inheritance. Autosomal recessive retinitis pigmentosa (ARRP) is the most common form in Japan. A genetic analysis was done to determine the prevalence of ARRP indirectly, to provide an estimation of changing trends in the overall prevalence of RP. Data on the frequency of consanguinity and marriage year of normal parents of 59 ARRP patients were obtained from a nationwide multicenter survey of typical retinitis pigmentosa conducted in 1990. The gene frequency of ARRP was 0.01145 (Dahlbergs formula). In 1990, the number of young symptomatic ARRP patients decreased, while the number of patients aged 40 years and older increased. The total number of symptomatic ARRP patients in 1990 was nearly 21% higher than in 1970. Despite a dramatic decline in consanguinity in recent decades in Japan, the number of ARRP patients has increased. This increase is attributed to greater longevity and overall population growth. Our results suggest that the total number of RP patients has not decreased, and may even have increased.

[Analysis of the long-term prognosis for conjunctival malignant melanomas in Japan].

PURPOSE To investigate the long-term prognosis for primary conjunctival malignant melanomas in Japan. MATERIALS & METHODS We conducted a survey of 61 cases which had been reported in a 38-year period (1959 to 1996). We gathered information regarding the survival of patients, the post-operative follow-up period, the causes of death, and recurrences. Answers were obtained segarding 51 cases (84%). Detailed progress was identified in 23 of these cases. The survival rates were calculated using the Kaplan-Meier method. RESULTS The survival rates were 95.1% after 1 year, 72.9% after 3 years, and 53.4% after 5 years. These values are relatively low compared with those reported in Europe and the United States.

A Case of Bilateral Continuous Central Retinal Artery Occlusion

BACKGROUND We report a case of bilateral simultaneous central retinal artery occlusion (CRAO). The time lag was 21 hours. CASE The patient was a 78-year-old woman. She had hypertension, arteriosclerosis, and bilateral thrombosis of the legs. Both eyes could only distinguish light and dark at the first medical examination. RESULTS We started steroid and urokinase therapy and used a vasodilator of peripheral vessels. When the patient left the hospital, visual acuity had improved to the ability of counting fingers (0.01 leftward 30 cm on the left). CONCLUSIONS Both visual field and color vision had improved slightly. We think this bilateral CRAO resulted from thrombosis of both central retinal arteries at almost the same time.

The developmental changes of ERGs on spontaneous retinal degeneration of Celestial goldfish

The Celestial goldfish, which belongs to the family of telescope-eye goldfish, displays unique spontaneous retinal degeneration associated with developmental anterodorsal protrusion of the eyeball. We observed concurrent changes in the electroretinogram. At the age of 75 days, the retinal layer was developed fully and the electroretinogram exhibited b-wave dominance similar to that of adult common goldfish. At the age of 105 days, when the eyeball began to protrude laterally, the b-wave amplitude decreased to 52% of its earlier developmental stage, with a prolonged peak time. Histologic change was observed in the retinal pigment epithelium and photoreceptor layers. At the age of 135 days, when the eyeball protruded further anterodorsally, the histologic changes extended to all retinal layers and the ERG b-wave was extinguished. Electrophysiologic and histologic changes in the Celestial goldfish eye were found to be proportional to the grade of eye protrusion. Since similar goldfish do not show these changes, however, the Celestial goldfish may be a new model of hereditary retinal degeneration.