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Masato Wakakura

Publications and source records attributed to Masato Wakakura.

10 recordsLinked to original sources
PubMed2006

Optic disc topography and peripapillary retinal nerve fiber layer thickness in nonarteritic ischemic optic neuropathy and open-angle glaucoma.

OBJECTIVE: To evaluate the results of scanning laser tomography and scanning laser polarimetry (SLP) and the correlations with visual field damage (VFD) in eyes with nonarteritic ischemic optic neuropathy (n-AION) compared with eyes with open-angle glaucoma (OAG). DESIGN: Cross-sectional study. PARTICIPANTS: Thirty-three eyes of 33 patients with n-AION and 33 eyes with OAG whose age and VFD evaluated with the Humphrey field analyzer were matched to those of the n-AION eyes. MAIN OUTCOME MEASURES: The parameters of optic disc topography obtained with the Heidelberg Retina Tomograph II (HRT II) and retinal nerve fiber layer (RNFL) thickness with GDx with variable corneal compensation and the correlation to VFD. RESULTS: The cup area, cup-to-disc area ratio, and mean cup depth were significantly smaller, and the cup shape measure more negative, in the n-AION eyes than in the OAG eyes (P<0.001), whereas rim area was significantly greater (P<0.001). Multivariate analyses showed that none of disc area, rim area, and mean cup depth in the n-AION eyes and only rim area (P = 0.029) in the OAG eyes was significantly associated with mean deviation (MD). Ellipse average of RNFL thickness significantly correlated with MD in the n-AION eyes (P = 0.045) and in the OAG eyes (P = 0.022). CONCLUSIONS: Disc topography of eyes with n-AION was quantitatively characterized by small and shallow cupping and a relatively large rim area compared to eyes with OAG matched for age and VFD. In eyes with n-AION, significant correlation with VFD was found only for the RNFL thickness evaluated with SLP but not for the HRT II parameters.

Aged↗
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↗
PubMed2006

[Adverse reaction after use of latanoprost in Japanese glaucoma patients].

PURPOSE: Although latanoprost has proven to have a strong hypotensive effect, some patients show adverse reactions such as eyelid pigmentation, iridial pigmentation, or hypertrichosis. We prospectively investigated these adverse reactions. SUBJECTS AND METHODS: One hundred and one Japanese glaucoma or ocular hypertension patients were included. Iridial, eyelid, and eyelash photographs were taken before and at 6 months after latanoprost treatment. Increased eyelid pigmentation, iridial pigmentation, eyelash pigmentation, vellus hair of the lid, and hypertrichosis were assessed from these photographs. The correlation between the incidence of these adverse reactions and the time of instillation, type of glaucoma, sex, age, or concomitantly used eye drops, and the overlap of these were evaluated. RESULTS: Increased pigmentation of the eyelid was found in 6 cases(5.9%), of the iris in 32 cases (31.7%), of the eyelashes in 29 cases (28.7%), vellus hair of the lid in 38 cases(37.6%), and hypertrichosis in 51 cases(50.5%). Pigmentation of the eyelid was more frequently observed in patients who used latanoprost concomitantly (16.7%) than in those who did not use anti-glaucomatous eye drops before latanoprost treatment (1.6%), or in those treated with latanoprost who had switched from other anti-glaucomatous eye drops (6.3%) (p= 0.03). CONCLUSIONS: The incidence of adverse reactions caused by latanoprost was higher in the eyelashes and iris than in the eyelid.

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↗