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Biomedical subjects

K Masumi

Publications and source records attributed to K Masumi.

6 recordsLinked to original sources
PubMed1989

[Analysis of the retinal blood flow by means of the blue field entoptic phenomenon and simulation of entoptic leucocytes with a personal-computer system].

A method was developed for determining the velocity of macular blood flow. Leukocytes flowing in the macular capillaries can be recognized when the retina is illuminated with blue light (blue field entoptic phenomenon). The motion of the leukocytes was simulated by a personal-computer system. The velocity of the macular blood flow was determined by adjusting the motion of the simulated corpuscles to that of the entoptically recognized leukocytes. The velocity of the maximum, minimum and mean macular blood flow were measured as 1.25 +/- 0.25, 0.42 +/- 0.11 and 0.80 +/- 0.14 mm/sec respectively. The mean coefficients of variation were 6.7%, 13.4% and 5.7% for each velocity. This method may be useful for the analysis of the retinal circulation and the diagnosis of retinal diseases.

Adult↗
PubMed1982

Supraliminal contrast sensitivity functions in recovered optic neuritis.

The supraliminal contrast sensitivity functions in patients with recovered optic neuritis were classified into three function types: 1) type with a decrease in sensitivity in the high and an increase in the low spatial frequency region, 2) type with flat shape as found in normal subjects, and 3) type with a decrease in the low and an increase in the high frequency region. These abnormal functions may be explained by an inhibitory interaction between two parallel channels of high and low frequency, which may have a dependence on the most central and the paracentral region in the visual fields, respectively. The measurements of the supraliminal contrast sensitivity functions are clinically useful for understanding the visual processes in cases with recovered optic neuritis.

Adult↗