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Dive into the research topics where Masanobu Motokura is active.

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Featured researches published by Masanobu Motokura.


Japanese Journal of Ophthalmology | 2000

Two-year follow-up study comparing primary vitrectomy with scleral buckling for macula-off rhegmatogenous retinal detachment.

Yusuke Oshima; Shigeki Yamanishi; Miki Sawa; Masanobu Motokura; Seiyo Harino; Kazuyuki Emi

PURPOSE To compare the anatomic and visual outcomes achieved by scleral buckling and primary vitrectomy for the repair of macula-off rhegmatogenous retinal detachment. METHODS The records were reviewed for a consecutive series of 167 patients (167 eyes) who were initially treated with scleral buckling or pars plana vitrectomy for primary macula-off retinal detachment. Patients were treated between January 1993 and December 1996. After adjustments for preoperative characteristics, data from 102 cases (55 scleral buckle cases and 47 primary vitrectomy cases) were used for the final comparison. There had been a minimum follow-up period of 24 months. RESULTS No significant differences in single-procedure reattachment incidence (91%), final success incidence (100%) and incidence of postoperative proliferative vitreoretinopathy development (4%) were observed between the two treatment groups. Preoperative visual acuity, preoperative intraocular pressure, and duration of macular detachment were the three best predictors of postoperative visual recovery in both groups. Favorable overall visual recovery was obtained postoperatively, with no significant differences between the two groups throughout the follow-up period. However, in the eyes with poor preoperative visual acuity (<0.1), ocular hypotony (intraocular pressure <7 mm Hg), or prolonged macular detachment (more than 7 days), visual recovery in the primary vitrectomy group was significantly better (P <.05) than in the scleral buckle group from the first postoperative month. CONCLUSION Both procedures achieved favorable anatomic and visual outcomes in the majority of patients with primary macula-off retinal detachment. Primary vitrectomy may be more effective than scleral buckling for achieving early visual rehabilitation in cases complicated by poor preoperative vision, ocular hypotony, and prolonged macular detachment.


British Journal of Ophthalmology | 1999

Quantitative assessment of macular thickness in normal subjects and patients with diabetic retinopathy by scanning retinal thickness analyser

Yusuke Oshima; Kazuyuki Emi; Shigeki Yamanishi; Masanobu Motokura

AIMS To evaluate the scanning retinal thickness analyser (RTA), a novel non-invasive imaging instrument, in diagnosing and quantitatively characterising diabetic macular oedema, and to investigate the relation between central macula thickness measured by RTA and other clinical examinations. METHODS Central macular thickness was measured using the RTA in 40 normal subjects and 60 patients with diabetic retinopathy. The reproducibility of the retinal thickness measurements was evaluated by calculating the mean of the inter- and intrasession variations. Central macular thickness was correlated with the results of visual acuity measurements, biomicroscopy, and fluorescein angiography. RESULTS Intra- and intersession reproducibility of the RTA in normal subjects was plus or minus 5.2% (16 μm) and plus or minus 6.1% (19 μm), respectively. The mean central macular thickness was 182 (SD 16) μm in normal subjects, 283 (116) μm in diabetic eyes without clinically significant macular oedema (CSMO), and 564 (168) μm in diabetic eyes with CSMO. Central macular thickness was significantly greater (p<0.001) in eyes with diabetic retinopathy than in normal subjects, even when macular thickening did not meet the standard for CSMO (p=0.019) measured by biomicroscopy. Although greater fluorescein leakage at the macula results in greater central macular thickness, only eyes with diffuse leakage had statistically significant macular thickening compared with normal subjects (p=0.022). Central macular thickness measured with the RTA was significantly correlated with the logarithmic converted visual acuity (r2 = 0.76) in diabetic eyes. CONCLUSION Scanning RTA, which has good reproducibility, might be useful to quantitatively detect and monitor macular thickening in diabetic retinopathy. Central macular thickness was highly correlated with logarithmic converted visual acuity in diabetic macular oedema.


Japanese Journal of Ophthalmology | 1999

Survey of surgical indications and results of primary pars plana vitrectomy for rhegmatogenous retinal detachments

Yusuke Oshima; Kazuyuki Emi; Masanobu Motokura; Shigeki Yamanishi

BACKGROUND Several surgical techniques to repair rhegmatogenous retinal detachment have been developed. Recently, both the method of reattaching the retina and of obtaining an early visual recovery are considered important factors when determining which surgical techniques to perform to treat retinal detachment. CASES The surgical outcome in a series of 63 consecutive patients, who were treated at Osaka Rosai Hospital between 1993 and 1996, was reviewed retrospectively to evaluate the efficacy of primary vitrectomy to treat uncomplicated rhegmatogenous retinal detachment associated with posterior hyaloid separation. The criteria for vitrectomy included the presence of not only posterior retinal breaks, but also of multiple peripheral retinal breaks. OBSERVATIONS The reattachment rate after the first surgery was 92.1% (58 eyes), and by the final examination it increased to 100%. Of the 46 eyes with macular detachment, good visual rehabilitation and a visual acuity improvement of 5 or more lines was obtained in 33 eyes (71.7%) by 1 month postoperatively. No statistically significant difference in the reattachment rate was found when eyes that underwent an encircling procedure were compared with those that did not. In eyes with lens opacity, cataract surgery was also performed and intraocular lenses were implanted uneventfully in all but one case with myopia. There was a high incidence (53.8%) of cataract progression in phakic eyes. However, no other serious complications, such as proliferative vitreoretinopathy, were found throughout the follow-up period. CONCLUSIONS The results indicate that vitrectomy performed to alleviate peripheral vitreoretinal traction is an effective surgical technique to treat primary rhegmatogenous retinal detachment. Vitrectomy combined with cataract surgery may also be a valuable surgical option in selected cases to maintain long-standing visual rehabilitation.


British Journal of Ophthalmology | 1997

Differentiating full thickness macular holes from impending macular holes and macular pseudoholes

Motokazu Tsujikawa; Masahito Ohji; Takashi Fujikado; Yoshihiro Saito; Masanobu Motokura; Ichiro Ishimoto; Yasuo Tano

AIMS The reliability of scanning laser ophthalmoscope (SLO) microperimetry in differentiating full thickness macular holes from macular pseudoholes and impending macular holes was evaluated. METHODS 106 eyes with the clinical diagnosis of full thickness macular holes, macular pseudoholes, and impending (stage 1) macular holes were examined for the presence of deep or relative scotoma using SLO microperimetry. The relation between these scotomas and the clinical diagnosis was studied. RESULTS Deep and relative scotomas were detected in all 57 eyes with clinically defined full thickness macular holes. In contrast, among 49 eyes diagnosed with macular pseudoholes or impending macular holes, no deep and only one relative scotoma was observed. The sensitivity of the presence of a deep scotoma as an indicator of the clinical diagnosis of a full thickness macular hole was 100% (57 of 57), and the specificity was 100% (49 of 49). The sensitivity of the presence of a relative scotoma was 100% (57 of 57) and the specificity was 98.0% (48 of 49). CONCLUSION With SLO microperimetry, full thickness macular holes can be precisely and objectively distinguished from other conditions that mimic macular holes.


American Journal of Ophthalmology | 1998

Chorioretinal damage caused by the excision of choroidal neovascularization

Motokazu Tsujikawa; Miki Sawa; John Michael Lewis; Masanobu Motokura; Kaoru Tsujikawa; Masahito Ohji; Yoshihiro Saito; Yasuo Tano

PURPOSE To determine whether choroidal neovascularization excision causes mechanical damage to the neurosensory retina, retinal pigment epithelium, or choriocapillaris. METHODS Prospectively, 18 eyes of 18 consecutive patients who underwent choroidal neovascularization excision were observed. Preoperatively and postoperatively, the integrity of the choriocapillaris circulation in the pathway of choroidal neovascularization extraction was studied by fluorescein and indocyanine green angiography. Using static scanning laser ophthalmoscope microperimetry, the presence of iatrogenic scotomas that developed postoperatively in the pathway of choroidal neovascularization extraction was also investigated. RESULTS Postoperatively, a choriocapillaris defect was detected in 17 (94.4%) of 18 cases. In 15 cases (83.3%), the choriocapillaris defect had a clear relationship to the pathway of choroidal neovascularization extraction. Postoperatively, a scotoma was present in 16 (88.9%) of 18 cases. In 14 cases (77.8%), the location of the scotoma had a clear relationship to the pathway of choroidal neovascularization extraction. CONCLUSION Surgical excision of choroidal neovascularization leads to severe damage of the choroid and retina in the pathway of the extracted choroidal neovascularization. The injury involves the neurosensory retina, retinal pigment epithelium, and choriocapillaris.


Retina-the Journal of Retinal and Vitreous Diseases | 2000

Optical cross-sectional evaluation of successfully repaired idiopathic macular holes by retinal thickness analyzer.

Shigeki Yamanishi; Yusuke Oshima; Kazuyuki Emi; Masanobu Motokura

Purpose: To describe optical cross‐sectional images of successfully repaired idiopathic macular holes and to determine the influences of epiretinal membranes and retinal pigment epithelial (RPE) changes on foveal reconstruction and the correlation between retinal thickness and postoperative visual acuity. Methods: In a prospective study, optical cross‐sectional imaging and retinal thickness measurement of the macula using a retinal thickness analyzer were performed on 63 eyes of 63 patients who underwent successful macular hole surgery. Results: Cross‐sectional images of foveal reconstruction were morphologically categorized into four patterns: normal fovea (23 eyes [37%]), cavernous fovea (19 eyes [30%]), flat fovea (11 eyes [17%]), and irregular fovea (10 eyes [16%]). Epiretinal membranes were observed in the last two groups (55% and 40%) and RPE changes were observed only in the irregular fovea group (16%). The mean retinal thickness of the fovea in all eyes was 213 ± 92 μm (mean ± SD; range, 93‐570 μxm), which varied significantly (P < 0.001) among the four groups. Linear regression analysis showed a significant correlation between retinal thickness at the fovea and logarithmic converted visual acuity (R2 = 0.42, P< 0.001). Conclusions: Structural features of foveal reconstruction following successful macular hole surgery involved four patters: normal fovea, cavernous fovea, flat fovea, and irregular fovea. Retinal thickness of the fovea, which varied among the groups, correlated with postoperative visual acuity. Postoperative epiretinal membrane formation and RPE damage may disturb normal foveal reconstruction and visual recovery.


American Journal of Ophthalmology | 1994

Chronic Ocular Ischemia Associated With the Eisenmenger's Syndrome

Seiyo Harino; Masanobu Motokura; Norikiyo Nishikawa; Masakatsu Fukuda; Atsuko Sasaoka; Juan E. Grunwald

We studied the ocular findings of two adult patients with the Eisenmengers syndrome who had atrial septal defects that were diagnosed before the age of 10 years but not operated on and pulmonary hypertension. Both eyes of these patients showed microaneurysms, multiple small blot hemorrhages, or capillary dilation in the temporal peripheral fundus. Multiple microaneurysms and retinal collaterals were confirmed by fluorescein angiography. One of the patients developed bilateral rubeosis iridis with slow progression. These retinal lesions and the rubeosis iridis are probably related to chronic ocular ischemia caused by chronic systemic hypoxia.


Graefes Archive for Clinical and Experimental Ophthalmology | 2002

Changes in fluorescein angiogram early after surgical removal of choroidal neovascularization in age-related macular degeneration.

Miki Sawa; Motohiro Kamei; Masahito Ohji; Masanobu Motokura; Yoshihiro Saito; Yasuo Tano

Abstract.Background: Retinal pigment epithelial (RPE) defects inevitably occur in surgical removal of choroidal neovascularization (CNV) in age-related macular degeneration (AMD). RPE can proliferate and cover the denuded area, but the healing process has not been investigated in humans. To understand the RPE wound-healing process, we estimated the changes in fluorescein angiograms early after CNV removal. Methods: Ten consecutive patients with exudative AMD underwent CNV removal without gas tamponade. Fluorescein angiography was performed within 4 days of surgery and again 1 or 2 weeks postoperatively. Areas of leakage were measured using a computer-assisted image analyser. The decreasing rate of leakage was calculated as the change in disc areas of leakage per day (DA/day). Results: The rates of decreasing leakage ranged from 0 to 0.42 DA/day (mean, 0.24±0.15 DA/day; median, 0.26 DA/day). The rate of decreasing leakage correlated with changes in visual acuity (r=0.642, P=0.0456). Conclusion: The retinal pigment epithelial wound after surgical removal of choroidal neovascularization may heal at the rate of 0.24 disc areas/day based on the blood retinal barrier function in patients with age-related macular degeneration. A faster rate of decreasing leakage may be associated with better visual prognosis.


Japanese Journal of Ophthalmology | 2002

Visual outcome of macular hole surgery with internal limiting membrane peeling

Shigeki Yamanishi; Kazuyuki Emi; Masanobu Motokura; Yusuke Oshima; Miyuki Nakayama; Masaki Watanabe

PURPOSE To evaluate the efficacy of the internal limiting membrane(ILM) peeling on macular hole surgery. METHODS A series of 102 patients(105 eyes) who underwent primary macular hole surgery between October 1994 and April 1999 was used for this retrospective study. The mean age was 65.6 +/- 7.1 years (mean +/- standard deviation). Of the study eyes, 34 eyes(32%) had a Stage II hole, 49 eyes(47%) had a Stage III hole, and 22 eyes(21%) had a Stage IV hole based on the Gass classification. Here we compared the surgical and visual outcome of the ILM peeling-treated group(treated group: 51 eyes) with those of ILM peeling-untreated group(untreated group: 54 eyes). RESULTS The hole closure rate after initial surgery was 98.0% in the treated group and 90.7% in the untreated group, and mean postoperative visual acuity, excluding cases where the hole was not closed by initial surgery, was 0.44 and 0.47, respectively. Visual improvement of 2 or more lines on Snellen chart was achieved in 84.3% and 57.4%(p < 0.01), and that of 4 or more lines in 54.9% and 25.9% (p < 0.01), respectively. Of the eyes with Stage II and III holes, visual outcome of the treated group was significantly better than that of the untreated group(p = 0.034, p = 0.037). In Stage IV, the initial closure rate of the treated group was significantly better than that of the untreated group(p = 0.02), but the visual outcome was not significantly different. CONCLUSION Vitreous surgery combined with ILM peeling for the management of idiopathic macular hole is effective not only on hole closure but also on visual recovery.


Japanese Journal of Ophthalmology | 1999

A Comparative Study of Visual Outcomes Following Primary Vitrectomy and Scleral Buckling Procedures to Manage Macular-off Rhegmatogenous Retinal Detachments

Yusuke Oshima; Kazuyuki Emi; Masanobu Motokura; Shigeki Yamanishi

PURPOSE To determine the difference between two types of retinal detachment surgery in postoperative visual recovery in the management of macular-off rhegmatogenous retinal detachment. METHODS We evaluated retrospectively the postoperative visual acuity (VA) in 37 patients who underwent primary vitrectomy (group V) and 39 patients treated with conventional scleral buckling (group S). RESULTS Although the mean preoperative VA in group V (0.03) was significantly worse (p = 0.04) than that in group S (0.06), there was no statistically significant difference between the groups in postoperative VA throughout the follow-up period. However, in the cases with poor preoperative VA (VA < 0.1), ocular hypotony (IOP < 7 mmHg), or prolonged macular detachment (duration > 7 days), the visual recovery was significantly better (p < 0.05) in group V than in group S from 1 month postoperatively. There were more eyes with a final VA of more than 0.5 in group V than in group S. When considering only the eyes with lenses spared intraoperatively, postoperative cataract progression resulting in secondary visual reduction was statistically significantly greater (p < 0.01) in group V (62%) than in group S (8%). CONCLUSIONS Primary vitrectomy is effective to attain early visual rehabilitation, especially to manage macula-off retinal detachments with poor preoperative VA, ocular hypotony, and prolonged macular detachment. To prevent a secondary visual reduction, cataract surgery combined with vitrectomy is recommended in selected cases.

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Masahito Ohji

Shiga University of Medical Science

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