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Dive into the research topics where Masafumi Kurimoto is active.

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Featured researches published by Masafumi Kurimoto.


Retina-the Journal of Retinal and Vitreous Diseases | 2005

Efficacy of surgical removal of the internal limiting membrane in diabetic cystoid macular edema.

Tetsushi Kimura; Junichi Kiryu; Hirokazu Nishiwaki; Hideyasu Oh; Kiyoshi Suzuma; Daisuke Watanabe; Masafumi Kurimoto; Hitoshi Takagi

Purpose: To evaluate the efficacy of surgical removal of the internal limiting membrane (ILM) in diabetic cystoid macular edema (CME). Methods: Prospective, noncomparative, interventional case series including 21 eyes of 18 consecutive patients with diabetic CME. Vitrectomy with separation of the posterior hyaloid and induction of posterior vitreous detachment had been performed previously on nine eyes. Pars plana vitrectomy for removal of the ILM was performed. Results: CME resolved in eyes that underwent initial vitrectomy and in those with long-standing (>1 year) CME after previous vitrectomy. Postoperative best-corrected visual acuity improved by ≥2 lines of a Snellen equivalent in 14 eyes (67%) (P < 0.01). The mean foveal thickness (distance between the inner retinal surface and the retinal pigment epithelium) decreased from 553 &mgr;m to 221 &mgr;m at 4 weeks (P < 0.001). No recurrences or deterioration of CME was observed during the entire follow-up period (mean, 17.8 months; range, 8–34 months). Conclusion: Surgical removal of the ILM might be an effective procedure for reducing CME in patients with diabetes. A prospective, randomized, controlled study is necessary to further evaluate the efficacy of the procedure.


Ophthalmology | 2013

Wide-Field Fundus Autofluorescence Imaging of Retinitis Pigmentosa

Akio Oishi; Ken Ogino; Yukiko Makiyama; Satoko Nakagawa; Masafumi Kurimoto; Nagahisa Yoshimura

PURPOSE To evaluate the clinical usefulness of wide-field fundus autofluorescence (FAF) imaging in patients with retinitis pigmentosa (RP). DESIGN Cross-sectional case series. PARTICIPANTS Seventy-five eyes of 75 patients with RP. METHODS We examined the eyes of the RP patients using the Optos 200Tx imaging system (Optos PLC, Dunfermline, United Kingdom) and identified abnormal FAF patterns such as ring hyperautofluorescence and patchy hypoautofluorescent areas. Patients with hyperautofluorescent rings or foveal hyperautofluorescence were compared with those without such findings. We determined the percentage area occupied by the FAF abnormalities within a defined region of the eye and examined the relationship between the percentage area of these abnormalities and the visual field area. Moreover, we categorized the patients into 3 different groups based on the presence of a patchy hypoautofluorescent lesion larger than 1 disc diameter: Group A consisted of those with patchy lesions smaller than 1 disc diameter, group B consisted of those with patchy lesions larger than 1 disc diameter but present in only 1 quadrant, and group C consisted of those with patchy lesions larger than 1 disc diameter and present in more than 1 quadrant. In addition, various clinical characteristics were compared among these 3 groups. MAIN OUTCOME MEASURES Predicting the visual field size and duration of the disease in RP patients based on FAF patterns. RESULTS Patients without hyperautofluorescent rings or foveal hyperautofluorescence had better visual acuity or mean deviation measured with a Humphrey perimeter. The total area of the abnormal FAF image correlated with the visual field area measured with a Goldmann perimeter (R = -0.64, P<0.001). The individuals with the large patchy hypofluorescent areas (i.e., larger than 1 disc diameter) were older than those with small patchy hypofluorescent areas (group A vs. groups B and C, P = 0.002 and P<0.001, respectively) and had experienced the symptoms for longer durations (group A vs. groups B and C, P<0.05 and P<0.001, respectively). CONCLUSIONS We can estimate the visual field in patients with RP using the objective measurements from wide-field FAF. The presence of patchy hypofluorescent lesions can be used an indicator of the duration of RP. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.


British Journal of Ophthalmology | 2012

Outer retinal circular structures in patients with Bietti crystalline retinopathy

Hiroshi Kojima; Atsushi Otani; Ken Ogino; Satoko Nakagawa; Yukiko Makiyama; Masafumi Kurimoto; Nagahisa Yoshimura

Background Bietti crystalline retinopathy (BCR) is a distinct retinal degenerative disease characterised by retinal degeneration with many yellow–white crystals located mainly at the posterior pole area. Using spectral domain-optical coherence tomography (SD-OCT), the structural change in retina was investigated. Methods Patients diagnosed with BCR (n=12), retinitis pigmentosa (RP, n=292) and cone dystrophy (n=16) were included in this study. The authors mainly examined fundus photographs and SD-OCT, infrared and fundus autofluorescence images of these patients. Results Crystalline deposits were detected in portions of the retinal pigment epithelium that lacked patchy degenerated lesions. SD-OCT revealed that most of the observed crystalline deposits were located adjacent to the inner side of retinal pigment epithelium layer. The change most frequently observed was circular hyper-refractive structures in the outer nuclear layer. Although the structures were considered to be previously reported “tubular formation” or “tubular degeneration”, we determined that many of these circular structures were slices of spherical structures and were typically noted in areas suspected of ongoing active degeneration. Conclusion BCR has characteristic structures in the outer nuclear layer. Although the incidence of the structure varies, it may be characteristic of retinal degeneration and can be found in many retinal degenerative diseases.


Retina-the Journal of Retinal and Vitreous Diseases | 2014

Prevalence and spatial distribution of cystoid spaces in retinitis pigmentosa: investigation with spectral domain optical coherence tomography.

Yukiko Makiyama; Akio Oishi; Atsushi Otani; Ken Ogino; Satoko Nakagawa; Masafumi Kurimoto; Nagahisa Yoshimura

Purpose: To investigate the prevalence and spatial distribution of cystoid spaces (CS) in retinitis pigmentosa patients with spectral domain optical coherence tomography. Methods: A total of 529 eyes of 275 patients with retinitis pigmentosa were examined with spectral domain optical coherence tomography. The presence or absence of CS was judged for each eye. Retinal layer and outer retinal status where the CS existed were also investigated. Statistical analysis was performed using 1 eye per 1 patient. Results: Cystoid spaces were present in 119 of 529 eyes (22.5%) of 74 of 275 patients (26.9%). There were no significant differences between the cases with and without CS except for central foveal thickness (P < 0.001). Cystoid spaces were noted in the inner nuclear layer in almost all eyes (98.6%), and outer nuclear layer/outer plexiform layer was also involved in many eyes (27.8%). Cystoid spaces were sometimes seen in ganglion cell layer (6.9%). Cystoid spaces were predominantly (78.9%) distributed in the relatively preserved retina where external limiting membrane was retained. The presence of epiretinal membrane or posterior vitreous adhesion was associated with the presence of CS (P < 0.001) but showed no relationship with the spatial location of CS (P = 1.000). Conclusion: The prevalence of CS in patients with retinitis pigmentosa was 26.9% and contrary to previous reports, most CS were present in inner nuclear layer. In addition, most CS were observed in relatively retained retina, which is compatible to the prevailing notion. Epiretinal membrane or posterior vitreous adhesion was also associated with the development of CS. The distribution of CS in inner and preserved retina may provide insight for the pathogenesis of CS in retinitis pigmentosa.


Investigative Ophthalmology & Visual Science | 2014

Wide-Field Fundus Autofluorescence Abnormalities and Visual Function in Patients With Cone and Cone-Rod Dystrophies

Maho Oishi; Akio Oishi; Ken Ogino; Yukiko Makiyama; Norimoto Gotoh; Masafumi Kurimoto; Nagahisa Yoshimura

PURPOSE To evaluate the clinical utility of wide-field fundus autofluorescence (FAF) in patients with cone dystrophy and cone-rod dystrophy. METHODS Sixteen patients with cone dystrophy (CD) and 41 patients with cone-rod dystrophy (CRD) were recruited at one institution. The right eye of each patient was included for analysis. We obtained wide-field FAF images using a ultra-widefield retinal imaging device and measured the area of abnormal FAF. The association between the area of abnormal FAF and the results of visual acuity measurements, kinetic perimetry, and electroretinography (ERG) were investigated. RESULTS The mean age of the participants was 51.4 ± 17.4 years, and the mean logarithm of the minimum angle of resolution was 1.00 ± 0.57. The area of abnormal FAF correlated with the scotoma measured by the Goldman perimetry I/4e isopter (ρ = 0.79, P < 0.001). The area also correlated with amplitudes of the rod ERG (ρ = -0.63, P < 0.001), combined ERG a-wave (ρ = -0.72, P < 0.001), combined ERG b-wave (ρ = -0.66, P < 0.001), cone ERG (ρ = -0.44, P = 0.001), and flicker ERG (ρ = -0.47, P < 0.001). CONCLUSIONS The extent of abnormal FAF reflects the severity of functional impairment in patients with cone-dominant retinal dystrophies. Fundus autofluorescence measurements are useful for predicting retinal function in these patients.


Investigative Ophthalmology & Visual Science | 2013

Clinical and immunological characterization of paraneoplastic retinopathy.

Yukiko Makiyama; Takanobu Kikuchi; Atsushi Otani; Akio Oishi; Satoko Nakagawa; Ken Ogino; Hiroshi Kojima; Masafumi Kurimoto; Nagahisa Yoshimura

PURPOSE To report the clinical and immunological characterization of paraneoplastic retinopathy (PR) and to investigate the association between spectral-domain optical coherence tomography (SDOCT) findings and the targets of autoantibodies in PR. METHODS We retrospectively enrolled eight patients (age range, 57-85 years; four men and four women) suspected of having PR. All patients underwent comprehensive ophthalmic examinations, including best-corrected visual acuity (BCVA) measurement, slitlamp examinations, kinetic visual field testing with Goldmann perimetry, electroretinography (ERG), fundus photography, fluorescein angiography, fundus autofluorescence (FAF), SDOCT, and serum sample tests (Western blot analysis and immunohistochemistry [IHC]). RESULTS Three patients had a history of malignant tumors, and four patients were newly diagnosed as having neoplastic tumors (small cell lung carcinoma [SCLC], thymoma, pancreatic neuroendocrine neoplasm, and colon cancer). Another de novo malignancy (SCLC) was detected in a patient with a history of malignancy (bladder cancer and liposarcoma). The BCVA in these patients ranged from hand motion to 1.5. Goldmann perimetry revealed island, ring-shaped, concentric, or central scotoma. All patients showed nonrecordable or reduced amplitude results on ERG. Fluorescein leakage was detected in five patients. Hyperautofluorescence and/or hypoautofluorescence on FAF was detected in six patients. The serum sample tests identified anti-retinal antibodies in all patients. Patients whose serum contained anti-photoreceptor or anti-retinal pigment epithelium antibody on IHC showed damage of the outer retina on SDOCT. CONCLUSIONS In this case series, PR was associated with a variety of neoplasms and autoantibodies. Spectral-domain OCT can be used to characterize morphologic changes, and the changes were associated with the targets of autoantibodies.


Clinical Ophthalmology | 2014

Association of retinal vessel attenuation with visual function in eyes with retinitis pigmentosa

Satoko Nakagawa; Akio Oishi; Ken Ogino; Yukiko Makiyama; Masafumi Kurimoto; Nagahisa Yoshimura

Purpose To investigate the association between visual changes and retinal vessel attenuation in patients with retinitis pigmentosa (RP). Design A retrospective, longitudinal, observational cohort study. Methods We analyzed 45 eyes from 45 subjects who were followed-up for ≥3 years at our clinic. Using the computer-based Interactive Vessel Analysis program, central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) were determined. Age- and sex-matched controls from normal subjects were selected from our archived fundus photograph library. Visual acuity, visual field area (Goldmann perimetry, V4e white test light), mean deviation (Humphrey perimetry, central 10-2 program), and central macular thickness (optical coherence tomography) were analyzed for correlations with CRAE and CRVE. Results Both CRAE and CRVE were significantly decreased in RP eyes (94.9±13.5 μm and 155.6±20.0 μm, respectively) compared with control eyes (138.1±14.7 μm and 215.0±20.4 μm, respectively, both P<0.001). After 3 years of follow-up, visual field area was associated with both CRAE (r=0.584, P<0.01) and CRVE (r=0.500, P=0.008). A significant association was also observed between mean deviation and CRAE (r=0.298, P=0.047). In eyes with RP, a narrower vessel caliber at baseline was associated with a larger decline in visual acuity over the 3-year follow-up interval (CRAE: r=−0.344, P=0.021; CRVE: r=−0.314, P=0.035). Conclusion Retinal vessel caliber is associated with some visual functions in patients with RP.


Japanese Journal of Ophthalmology | 2013

Concentric division of 10° visual field tests in retinitis pigmentosa

Ken Ogino; Atsushi Otani; Akio Oishi; Masafumi Kurimoto; Nagahisa Yoshimura

PurposeThe purpose of this study was to estimate the optimal size of visual field test for detecting longitudinal changes in retinitis pigmentosa (RP) by dividing the visual field.MethodsWe reviewed the results of 10° static visual field tests in 19 eyes of 19 RP patients. Sixty-eight numeric value points were divided into two area types: concentric areas (A1, A1–2, A1–3, A1–4, A1–5, A1–6) and circular areas (A1, A2, A3, A4, A5, A6). Serial values of mean sensitivity in each area of each patient were analyzed by linear regression.ResultsAnalysis of the concentric areas showed that 10 of 19 eyes had the best R2 value in the most central area, A1. Analysis of circular areas showed that 7 of 19 eyes had the steepest slope of decline in A1. The inner-segment/outer-segment (IS/OS) line was significantly shorter in eyes with low variability and evident disease progression in the inner areas than the ones in the outer areas.ConclusionsThe optimal size of monitoring RP progression was different in each case and may depend on the remaining morphology of the outer retina.


Clinical Ophthalmology | 2015

Radial fundus autofluorescence in the periphery in patients with X-linked retinitis pigmentosa.

Ken Ogino; Maho Oishi; Akio Oishi; Satoshi Morooka; Masako Sugahara; Norimoto Gotoh; Masafumi Kurimoto; Nagahisa Yoshimura

Purpose To describe the peripheral autofluorescence images and clinical features of patients with retinal dystrophy who showed radial fundus autofluorescence (FAF) at the posterior pole. Methods The authors retrospectively reviewed pooled wide-field FAF images of 711 patients with retinal dystrophy and 56 family members. Results Eleven eyes of seven women exhibited radial FAF at the posterior pole. Wide-field FAF showed extension of the radial pattern to the periphery in all eyes except one. One woman showed radial hyper-FAF only in the periphery, not at the posterior pole. These eight individuals were X-linked retinitis pigmentosa patients or carriers. The tapetal-like reflex was not observed in their color fundus photographs. The peripheral visual field showed wedge-shaped restriction in some individuals. Conclusion Wide-field FAF imaging can depict radial FAF not only at the posterior pole but also in the periphery in X-linked retinitis pigmentosa carriers. The authors therefore agree with previous reports that radial FAF may be a hallmark of X-linked retinitis pigmentosa.


Advances in Experimental Medicine and Biology | 2016

Intra-familial Similarity of Wide-Field Fundus Autofluorescence in Inherited Retinal Dystrophy.

Yuka Furutani; Ken Ogino; Akio Oishi; Norimoto Gotoh; Yukiko Makiyama; Maho Oishi; Masafumi Kurimoto; Nagahisa Yoshimura

To examine the similarity of wide-field fundus autofluorescence (FAF) imaging in inherited retinal dystrophy between siblings and between parents and their children. The subjects included 17 siblings (12 with retinitis pigmentosa and 5 with cone rod dystrophy) and 10 parent-child pairs (8 with retinitis pigmentosa and 2 with cone rod dystrophy). We quantified the similarity of wide-field FAF using image processing techniques of cropping, binarization, superimposition, and subtraction. The estimated similarity of the siblings was compared with that of the parent-child pairs and that of the age-matched unrelated patients. The similarity between siblings was significantly higher that of parent-child pairs or that of age-matched unrelated patients (P = 0.004 and P = 0.049, respectively). Wide-field FAF images were similar between siblings with inherited retinal dystrophy but different between parent-child pairs. This suggests that aging is a confounding factor in genotype-phenotype correlation studies.

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