PubMed Health⌕ Search

Biomedical subjects

Masato Wakakura

Publications and source records attributed to Masato Wakakura.

8 recordsLinked to original sources
PubMed2006

[Evaluation of the effect of aging on retinal nerve fiber thickness of normal Japanese measured by optical coherence tomography].

PURPOSE: To determine the normal retinal nerve fiber layer (RNFL) thickness as measured by optical coherence tomography (OCT), and to evaluate the relationship between RNFL thickness in healthy Japanese and their age. METHODS: One hundred healthy Japanese subjects were enrolled. The RNFL thickness was measured using OCT with three circle scans 3.4 mm in diameter. RESULT: The mean thickness of RNFL measured around the optic disc was 108 +/- 13.5 microm. The average RNFL thickness in the temporal, superior, nasal, and inferior quadrants was 80 +/- 15.9 microm, 132 +/- 20.7 microm, 80 +/- 17.0 microm and 136 +/- 20.0 microm, respectively. There was a statistically significant negative correlation between age and the average RNFL thickness around the disc, and in the temporal quadrant. Using 30-degree segments, there were negative correlations between age and RNFL thickness in temporal-superior and temporal-inferior segments. CONCLUSION: RNFL thickness in healthy Japanese subjects measured by OCT decreased with age in the temporal-superior and temporal-inferior quadrants. Our results suggested that the regional and age-related differences in RNFL thickness must be taken into consideration before making clinical interpretations of the RNFL abnormalities measured by OCT.

Adolescent↗
PubMed2005

Linezolid-induced optic neuropathy.

PURPOSE: To report a case of optic neuropathy associated with prolonged use of a new antibiotic, linezolid. DESIGN: Interventional case report. METHODS: Optic and peripheral neuropathy occurred in a 27-year-old woman who was undergoing prolonged linezolid therapy for osteomyelitis. The use of corticosteroid exacerbated visual loss. Discontinuation of the linezolid therapy resulted in marked improvement of optic neuropathy. RESULTS: Linezolid-induced optic neuropathy was diagnosed in this case, because prolonged linezolid therapy was performed at a higher dose than usual and because the patient recovered after linezolid therapy was discontinued. CONCLUSIONS: With prolonged linezolid therapy, ophthalmologists should be aware that bilateral optic neuropathy can occur and that corticosteroids are not indicated for this neuropathy.

Acetamides↗
PubMedDate not supplied

Oscillopsia associated with dysfunction of visual cortex.

PURPOSE: To investigate the cause of oscillopsia without nystagmus or vestibular dysfunction in a 31-year-old man with no past history of serious illness. METHODS: The changes in the regional cerebral blood flow elicited by visual stimuli were studied by positron emission tomography (PET) in the patient and were compared with changes in normal subjects. The primary visual cortex (PVC) and area V5 were defined on Talairach coordinates, as shown in previous PET studies, and were confirmed with their activation patterns in our subjects. RESULTS: Flicker stimulation (8 Hz) and a stationary random dot pattern activated area V5 in the patient, but not in the six normal controls. A moving random dot pattern activated both the PVC and the extra-striate cortex in both the patient and the controls. CONCLUSIONS: Oscillopsia in this case is associated with dysfunction of the visual cortices and may be caused by it.

Adult↗
PubMedDate not supplied

Influenza retinitis: association with influenza encephalitis.

PURPOSE: To report an unusual case of retinitis caused by influenza virus. CASE: A 30-year-old male claimed partial color blindness after recovery from influenza encephalitis. Visual acuity was 0.3 in the right eye and 0.03 in the left. An ophthalmoscopic fundus examination looked normal, but fluorescein angiography revealed granular hyperfluorescence with multiple dark circular lesions at the posterior pole of both eyes. Serological testing revealed an influenza A virus infection. With corticosteroid pulse therapy (3 days) followed by oral methyl prednisolone for 1 month, visual acuity gradually recovered. Over the following 2-year period, visual acuity has recovered to 1.2 in both eyes, but color sensation still remains impaired. CONCLUSIONS: Influenza encephalitis can cause visual loss due to retinitis at the posterior pole.

Administration, Oral↗