Ryusaburo Mori
Nihon University
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Featured researches published by Ryusaburo Mori.
British Journal of Ophthalmology | 2005
Mitsuko Yuzawa; Ryusaburo Mori; Akiyuki Kawamura
Background/aim: There are two theories on the pathogenesis of polypoidal choroidal vasculopathy (PCV): variants in choroidal neovascularisation (CNV) and inner choroidal vessel abnormalities. On indocyanine green angiography (IGA) with a video camera system, PCV has a characteristic appearance, but inadequate image quality has made detailed interpretation difficult. This study aims to improve imaging, using confocal scanning laser ophthalmoscopy (SLO), to elucidate the pathogenesis of PCV. Methods: High speed IGA with confocal SLO of 45 eyes (44 patients) showed typical PCV findings of a branching vascular network and polypoidal lesions. Results: Vessels comprising branching networks began to fill simultaneously with the surrounding choroidal arteries in 38 eyes. Small numbers of vessels filling within a branching network, in the arterial and arteriovenous phases of IGA, showed focal dilatation, constriction, and tortuousity. Vessel abnormalities, corresponding to polypoidal lesions, existed within a network in eight eyes and included loops similar in calibre to network vessels, and numerous microaneurysmal dilatations of small vessels. Vessel pulsation was seen in 24 eyes. Conclusion: PCV is caused by inner choroidal vessel abnormalities, not CNV.
Investigative Ophthalmology & Visual Science | 2008
Hiroyuki Nakashizuka; Masako Mitsumata; Shigekuni Okisaka; Hiroyuki Shimada; Akiyuki Kawamura; Ryusaburo Mori; Mitsuko Yuzawa
PURPOSE To elucidate the pathogenic mechanism of polypoidal choroidal vasculopathy (PCV) based on histopathologic findings. METHODS Specimens obtained by surgical excision of PCV from five eyes of five patients (mean age, 75.6 +/- 3.1 years) were studied histopathologically. Immunohistochemical studies were also performed to identify CD34, vascular endothelial growth factor (VEGF), CD68, alpha-smooth muscle actin (alpha-SMA) and hypoxia-inducible factor (HIF)-1alpha. RESULTS Hyalinization of choroidal vessels and massive exudation of fibrin and blood plasma were observed in all the specimens of PCV lesions. Some blood vessels were located above the RPE in two of the five eyes. Immunohistochemically, CD68-positive cells were detected around the hyalinized vessels. There were no alpha-SMA-positive cells in the vessels of PCV. CD34 staining showed endothelial discontinuity. Vascular endothelial cells within the PCV specimens were negative for VEGF. HIF-1alpha positive inflammatory cells were located in the stroma of specimens. CONCLUSIONS Hyalinization of choroidal vessels, like arteriosclerosis, is characteristic of PCV.
Retina-the Journal of Retinal and Vitreous Diseases | 2008
Eriko Akaza; Ryusaburo Mori; Mitsuko Yuzawa
Purpose: This study evaluated the results of photodynamic therapy (PDT) for polypoidal choroidal vasculopathy (PCV) 24 months or more after treatment. Methods: The study involved 47 eyes of 47 patients with PCV followed for 24 months or more after the first PDT. Fundus appearance, indocyanine green angiographic findings, and visual acuity (VA) were compared before PDT, and then at 3 months, 12 months, and the final visit after the first PDT. Results: At the final visit, VA was preserved or improved in 37 (79%) of the 47 eyes. Recurrence of polypoidal lesions was noted in 30 eyes (64%). An abnormal branching vascular network persisted in all subjects. In 26 of the 30 eyes exhibited recurrence of polypoidal lesions, which appeared in the periphery of the expanded abnormal branching vascular network. Conclusion: Patients with PCV need to be followed for long periods of time after PDT because of the high incidence of polypoidal lesion recurrence. However, since polypoidal lesions often recur outside the fovea, and thus have little effect on VA, PDT can be expected to exert long-term efficacy in treating PCV.
Ophthalmology | 2008
Hiroyuki Shimada; Hiroyuki Nakashizuka; Takayuki Hattori; Ryusaburo Mori; Yoshihiro Mizutani; Mitsuko Yuzawa
PURPOSE To compare endophthalmitis incidence after inpatient 20-gauge (20-G) and 25-G vitrectomies, and to examine the causes and prevention of postvitrectomy endophthalmitis. DESIGN Retrospective, interventional, comparative cohort study. PARTICIPANTS Six thousand nine hundred thirty-five consecutive patients undergoing pars plana vitrectomy. METHODS We compared the incidence of endophthalmitis in 3592 consecutive eyes that underwent 20-G vitrectomy between January 2000 and September 2004, and 3343 consecutive eyes that underwent 25-G vitrectomy between April 2004 and December 2007. For 25-G vitrectomy, 542 eyes with sclerotomies produced by straight incision and 2801 eyes with angled incisions were also compared. From 85 eyes that underwent 20-G vitrectomy and 128 eyes that underwent 25-G vitrectomy, ocular surface irrigation fluid and vitreous samples were collected at the end of surgery for bacterial culture. MAIN OUTCOME MEASURES Incidence of postvitrectomy endophthalmitis. RESULTS The incidence of postoperative endophthalmitis was 0.0278% (1 of 3592 eyes) for 20-G vitrectomies and 0.0299% (1 of 3343 eyes) for 25-G vitrectomies, with no significant difference. Two eyes developed endophthalmitis after vitrectomy, and visual acuity deteriorated to no light perception despite emergency vitreous surgery. The causative bacteria were methicillin-resistant Staphylococcus aureus and Enterococcus faecali; both were resistant to postoperative antibiotics. In 25-G vitrectomy, the endophthalmitis incidence was 0.18% (1/542 eyes) for straight incision versus 0% (0/2801 eyes) for angled incision, with no significant difference (P = 0.1621). Bacterial contamination rates in ocular surface irrigation fluid and the vitreous were 5.9% (5/85 eyes) and 1.2% (1/85 eyes), respectively, in 20-G vitrectomies, and 5.5% (7/128 eyes) and 2.3% (3/128 eyes) in 25-G vitrectomies, with no significant difference. CONCLUSIONS The incidence of endophthalmitis was 0.03% for both 20-G and 25-G vitrectomies. This is the first data set to demonstrate no statistically significant difference between endophthalmitis rates in 20-G and 25-G vitrectomy. At the completion of 25-G vitrectomy, the ocular surface irrigation fluid and vitreous were, on rare occasion, contaminated by antibiotic-resistant bacteria. In 25-G vitrectomy, conjunctival irrigation, ensuring sclerotomy closure, and excision of peripheral vitreous may contribute to the prevention of postvitrectomy endophthalmitis. FINANCIAL DISCLOSURE(S) The authors have no proprietary or commercial interest in any materials discussed in this article.
Ophthalmology | 2009
Hiroyuki Shimada; Hiroyuki Nakashizuka; Takayuki Hattori; Ryusaburo Mori; Yoshihiro Mizutani; Mitsuko Yuzawa
PURPOSE To compare methods of removing epiretinal membranes (ERM) and evaluate the usefulness of the double brilliant blue G (BBG) staining and double-peeling method. DESIGN Prospective, interventional case series. PARTICIPANTS We followed 246 consecutive patients who underwent pars plana vitrectomy to remove ERM and for > or =12 months. METHODS Of the 246 eyes, 104 underwent single ERM peeling using indocyanine green staining, and 142 underwent ERM peeling by 1 of the 3 following methods: without staining in 46 eyes, triamcinolone acetonide staining in 42, and BBG staining in 54. Peeling of residual internal limiting membrane (ILM) was then conducted using BBG. In the latter group, the ILM that remained after the initial peeling procedure was evaluated macroscopically with BBG staining and also histopathologically. In 6 eyes requiring reoperation owing to ERM recurrence, the peeled ERM was examined histopathologically. MAIN OUTCOME MEASURES Postoperative visual acuity and recurrence of ERM. RESULTS The ERM recurrence rate was 16.3% (17 eyes) and the reoperation rate was 5.8% (6 eyes) among the 104 eyes that underwent single ERM peeling, compared with 0% in 142 eyes with double ERM and ILM peeling. Although the ERM recurrence rate was significantly lower with double peeling, postoperative visual acuity did not differ between the 2 methods. The 3 ERM peeling methods differed in the rate and extent of residual ILM, and the lowest rate (21/54 eyes; 39%) was achieved with BBG staining (P<0.0001). Histopathologic examination of the ILM remaining after ERM peeling detected remnant ERM cells on the ILM. Histopathologic examination of the peeled ERM in 6 eyes with ERM recurrence showed residual ILM to serve as a scaffold for cell proliferation. CONCLUSIONS This study verified that ERM recurrence arises from remnant ERM components on the ILM, which proliferate using the ILM as a scaffold, and that complete ILM removal seems to reduce the risk of recurrence. Brilliant blue G with good affinity for the ILM facilitates simultaneous ERM and ILM peeling in many cases, and BBG contact with the retina in the second staining has no apparent effect on visual acuity. Double BBG staining and double peeling is useful for ERM treatment.
Japanese Journal of Ophthalmology | 2007
Eriko Akaza; Mitsuko Yuzawa; Matsumoto Y; Shiho Kashiwakura; Kyoko Fujita; Ryusaburo Mori
PurposeTo determine the efficacy of photodynamic therapy (PDT) with verteporfin for polypoidal choroidal vasculopathy (PCV).MethodsPDT was performed in 35 patients (35 eyes) with PCV. We evaluated the number of treatments and compared visual acuity (VA), ophthalmological findings, and changes in polypoidal lesions and branching vascular networks by measuring lesion diameters using Heidelberg retina angiography before PDT, and then every 3 months for 1 year after PDT.ResultsThe mean annual number of treatment sessions was 2.2. VA was improved or maintained in 80% of the patients. Retinal pigment epithelium detachment, retinal detachment, hemorrhage, and/or exudates disappeared in 69%, and leakage resolved in 74% of the patients. Polypoidal lesions disappeared completely on indocyanine green angiography in 83% of the patients. All branching vascular networks persisted. Polypoidal lesions had recurred at the termini of the remaining branching vascular networks at 9 months after the first PDT in two eyes and at 12 months in one eye.ConclusionsPDT with verteporfin for PCV appears to improve or maintain VA for the first posttreatment year. Approximately 70% of PCV cases showed improved ophthalmoscopic findings. However, as polypoidal lesions recur after PDT in some cases, further study is needed to confirm the long-term efficacy of PDT for PCV. Jpn J Ophthalmol 2007;51:270–277 @ Japanese Ophthalmological Society 2007
Japanese Journal of Ophthalmology | 2004
Masami Nakajima; Mitsuko Yuzawa; Hiroyuki Shimada; Ryusaburo Mori
PurposeTo analyze the histopathology of polypoidal choroidal vasculopathy (PCV) and choroidal neovascularization (CNV) developing from PCV, the authors evaluated correlations between pathological findings and the findings of preoperative indocyanine green angiography (IA).MethodsTwo specimens were obtained during CNV excision associated with PCV. PCV tissue was excised with the CNV. The specimens were examined by light microscopy.ResultsIn one case, IA revealed polypoidal lesions exhibiting hyperfluorescence in both the early and the late phase, and in the affected area, abnormally dilated vessels were identified histologically underneath relatively healthy retinal pigment epithelium (RPE). In the other case, the polypoidal lesions seen on IA showed early hyperfluorescence and late isofluorescence, and dilated vessels were observed under the RPE; perivascular amorphous material was present. The RPE adhered to the side of the choroid, and there was CNV under the neurosensory retina in both cases. The CNV had numerous vascular lumens, was not surrounded by the RPE, and exhibited few fibrous components.ConclusionsIA findings vary depending on the condition of the RPE located above the PCV and the extent of amorphous material around the PCV.
Japanese Journal of Ophthalmology | 2011
Eriko Akaza; Mitsuko Yuzawa; Ryusaburo Mori
PurposeTo evaluate the visual outcomes and changes in abnormal vascular networks and polypoidal lesions of polypoidal choroidal vasculopathy (PCV) 3 years after photodynamic therapy (PDT).MethodsWe studied 43 eyes of 43 patients with PCV for 3 years. Fundus appearance, fluorescein angiography (FA) and indocyanine green angiography (IA) findings, and visual acuity (VA) before the initial PDT were compared with those 3 months, 1 year, 2 years, and 3 years after treatment.ResultsIn 24 of the 43 eyes, enlargement of the abnormal vascular network continued in a manner similar to that before PDT on IA; in eight eyes, transformation into polypoidal choroidal neovascularization (CNV) with enlargement was detected; and two eyes had the appearance of classic CNV on FA. Polypoidal lesions recurred at 3 years in 33 of the 43 eyes (77%). Mean VA (logarithm of the minimum angle of resolution) of all 43 eyes decreased to below baseline at 3 years after the initial PDT. This decrease can be explained by foveal atrophy after absorption of recurrent hemorrhagic or exudative detachment.ConclusionLong-term visual outcomes were not good owing to the high frequency of recurrent polypoidal lesions, as well as enlargement and neovascular changes involving abnormal vascular networks.
Acta Ophthalmologica | 2013
Akiyuki Kawamura; Mitsuko Yuzawa; Ryusaburo Mori; Miho Haruyama; Koji Tanaka
Purpose: We assessed the characteristic indocyanine green angiographic (ICGA) and spectral domain optical coherence tomographic (SD‐OCT) findings of two types of polypoidal choroidal vasculopathy (PCV), distinguishable by different filling patterns on ICGA.
Investigative Ophthalmology & Visual Science | 2011
Koji Tanaka; Tomohiro Nakayama; Ryusaburo Mori; Naoyuki Sato; Akiyuki Kawamura; Yoshihiro Mizutani; Mitsuko Yuzawa
PURPOSE To clarify whether complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2) genotypes are associated with subtypes of polypoidal choroidal vasculopathy (PCV), such as polypoidal choroidal neovascularization (CNV) and typical PCV. METHODS Two hundred eighty-seven patients were categorized as having polypoidal CNV (85 patients) or typical PCV (202 patients) on the basis of indocyanine green angiographic findings. In total, 277 subjects without age-related macular degeneration (i.e., free of PCV and CNV), served as controls. I62V (rs800292) in the CFH gene and A69S (rs10490924) in the ARMS2 gene were genotyped, and case-control studies were performed in subjects with these PCV subtypes. RESULTS The polypoidal CNV group included no subjects homozygous for the A/A genotype of rs800292, whereas 7% of the typical PCV group had this genotype. Case-control studies of polypoidal CNV and typical PCV showed significant differences in all distributions of rs10490924 between these two groups. In contrast, the distributions of rs10490924 did not differ between the typical PCV and control groups. Logistic regression analysis with adjustment for confounding factors showed the distributions of rs10490924 to differ significantly between the controls and polypoidal CNV cases (P = 2.1 × 10(-10); OR, 10.87). The T/T genotype was significantly more common in the polypoidal CNV than in the typical PCV group (P = 3.6 × 10(-14); OR, 19.61). CONCLUSIONS PCV may be genetically divisible into polypoidal CNV and typical PCV. The rs800292 variant of the CFH gene is a potential marker for typical CNV. The rs10490924 variant of the ARMS2 gene was shown to be associated with polypoidal CNV. Typical PCV was not associated with this variant.