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Dive into the research topics where Hiroshi Oyamada is active.

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Featured researches published by Hiroshi Oyamada.


Retina-the Journal of Retinal and Vitreous Diseases | 2011

Subfoveal choroidal thickness after treatment of Vogt-Koyanagi-Harada disease.

Ichiro Maruko; Tomohiro Iida; Yukinori Sugano; Hiroshi Oyamada; Tetsuju Sekiryu; Takamitsu Fujiwara; Richard F. Spaide

Purpose: To evaluate the subfoveal choroidal thickness in Vogt-Koyanagi-Harada (VKH) disease using enhanced depth imaging optical coherence tomography. Methods: Retrospective observational study. Subfoveal choroidal thickness was measured using enhanced depth imaging optical coherence tomography, in which the optical coherence tomography instrument was placed close enough to the eye to obtain an inverted image, which was averaged for 100 scans. All patients were diagnosed as having the ocular findings of VKH disease with or without extraocular disorders. The patients were followed during their initial treatment with corticosteroids. Results: All 8 patients (16 eyes) with acute phase VKH disease presented with thickening of the choroid. The serous retinal detachment disappeared in 1 month after corticosteroid treatment. The mean choroidal thickness in 16 eyes decreased from 805 ± 173 μm at the first visit to 524 ± 151 μm at 3 days (P < 0.001) and 341 ± 70 μm by 2 weeks (P < 0.001). Conclusion: Patients with active VKH disease have markedly thickened choroids, possibly related not only to inflammatory infiltration but also to increased exudation. Both the choroidal thickness and the exudative retinal detachment decreased quickly with corticosteroid treatment. Enhanced depth imaging optical coherence tomography can be used to evaluate the choroidal involvement in VKH disease in the acute stages and may prove useful in the diagnosis and management of this disease noninvasively.


Investigative Ophthalmology & Visual Science | 2011

Morphologic Choroidal and Scleral Changes at the Macula in Tilted Disc Syndrome with Staphyloma Using Optical Coherence Tomography

Ichiro Maruko; Tomohiro Iida; Yukinori Sugano; Hiroshi Oyamada; Tetsuju Sekiryu

PURPOSE To evaluate the macular choroidal and scleral changes in tilted disc syndrome (TDS) with staphyloma using optical coherence tomography (OCT) to determine the mechanism of serous retinal detachment (SRD) formation. METHODS All eyes underwent fluorescein (FA) and indocyanine green angiography (ICGA) in this retrospective, observational study. Enhanced-depth imaging (EDI) OCT and prototype high-penetration (HP) OCT were used to examine the choroid and sclera, respectively, at the upper and lower optical areas and the subfovea on vertical OCT sections. RESULTS Twenty-four eyes with TDS with inferior staphyloma were included. FA showed the macular area with the superior edge of staphyloma had a granular hyperfluorescent pattern and ICGA showed belt-like hypofluorescence. OCT showed SRDs in seven eyes. The mean EDI-OCT choroidal thicknesses in 19 eyes were: upper area, 211 ± 79 μm; subfovea, 153 ± 70 μm; and lower area, 158 ± 42 μm. The mean subfoveal and lower choroid were significantly (P < 0.01 for both) thinner than the upper area. The mean HP-OCT scleral thicknesses in 14 eyes were: upper area, 414 ± 36 μm; subfovea, 493 ± 40 μm; and lower area, 398 ± 83 μm. The subfoveal sclera was significantly (P < 0.01) thicker than the others. CONCLUSIONS The subfoveal choroid was relatively thin and the subfoveal sclera thickened in TDS with a staphyloma edge at the macula. The area with retinal pigment epithelial (RPE) atrophy was hyperfluorescent on FA; choriocapillaris occlusion was hypofluorescent on ICGA. Characteristic anatomic subfoveal scleral alterations might lead to a thinner choroid and inhibit chorioscleral outflow; a secondary RPE disorder subsequently could cause SRDs.


American Journal of Ophthalmology | 2013

Choroidal Thickness Changes After Intravitreal Ranibizumab and Photodynamic Therapy in Recurrent Polypoidal Choroidal Vasculopathy

Ichiro Maruko; Tomohiro Iida; Hiroshi Oyamada; Yukinori Sugano; Akira Ojima; Tetsuju Sekiryu

PURPOSE To evaluate subfoveal choroidal thickness changes in cases with recurrent polypoidal choroidal vasculopathy (PCV) after combination therapy with intravitreal ranibizumab and photodynamic therapy (PDT). DESIGN Retrospective observational case series study. METHODS We measured subfoveal choroidal thickness in PCV using optical coherence tomography (OCT) before and after PDT. In recurrent cases, the choroidal thickness was measured at the time of the recurrence. In nonrecurrent cases, choroidal thickness was measured 1 year after PDT. RESULTS Combination therapy was performed in 27 eyes (27 patients). Polypoidal lesions regressed within 3 months after initial treatment in all eyes. Retreatment was needed in 10 of 27 eyes (37.0%) after more than 3 months of follow-up. In recurrent cases, subfoveal choroid decreased from 188 μm at baseline to 157 μm 3 months after PDT (P < .01); however, choroidal thickness increased to 179 μm with recurrence (P = .54 compared to baseline; average, 8.0 months). In nonrecurrent cases, subfoveal choroid decreased from 257 μm at baseline to 210 μm 3 months after PDT and 212 μm 1 year after PDT (P < .01, respectively). CONCLUSION Subfoveal choroidal thickness in PCV at the time of recurrence returned to the baseline level after choroidal thinning as a result of PDT treatment. Choroidal thickness changes after PDT examined using OCT may reflect disease activity in PCV.


Investigative Ophthalmology & Visual Science | 2012

Morphologic analysis in pathologic myopia using high-penetration optical coherence tomography.

Ichiro Maruko; Tomohiro Iida; Yukinori Sugano; Hiroshi Oyamada; Masahiro Akiba; Tetsuju Sekiryu

PURPOSE We evaluated retrospectively the morphologic choroidal and scleral characteristics in eyes with pathologic myopia using high-penetration optical coherence tomography (HP-OCT) or swept-source OCT (SS-OCT). METHODS The subfoveal choroidal and scleral thicknesses were measured using the prototype HP-OCT with a 1060 nm light source. We also measured the scleral thickness 3 mm superior, inferior, nasal, and temporal to the fovea on the horizontal and vertical OCT sections. The axial length (AL) in all eyes was measured using optical biometry. RESULTS We examined 58 eyes of 35 patients (7 men and 28 women, mean age 65.5 years) with an AL exceeding 26.5 mm. The mean AL was 29.0 ± 1.4 mm. The full-thickness choroid and sclera were visualized in all eyes. The mean subfoveal choroidal and scleral thicknesses were 52 ± 38 and 335 ± 130 μm, respectively. The mean scleral thicknesses 3 mm superior, inferior, nasal, and temporal to the fovea were 266 ± 78 (n = 57), 259 ± 72 (n = 56), 324 ± 109 (n = 39), and 253 ± 79 (n = 58) μm, respectively. The subfoveal sclera was thicker than 3 mm outside the fovea (P < 0.05, for each comparison). CONCLUSIONS The full-thickness choroid and sclera in all eyes with pathologic myopia were visualized using a prototype HP-OCT. The subfoveal sclera was thicker than 3 mm outside the fovea. HP-OCT is a useful tool for morphologic analyses of pathologic myopia.


Journal of Histochemistry and Cytochemistry | 2007

Distribution and Variable Expression of Secretory Pathway Protein Reticulocalbin in Normal Human Organs and Non-neoplastic Pathological Conditions

Takeaki Fukuda; Hiroshi Oyamada; Takuma Isshiki; Masahiro Maeda; Takashi Kusakabe; Ayumi Hozumi; Tomiko Yamaguchi; Toshihiko Igarashi; Hidehiro Hasegawa; Tsutomu Seidoh; Toshimitsu Suzuki

Reticulocalbin (RCN) is one member of the Ca2+-binding proteins in the secretory pathway and is localized in the endoplasmic reticulum. RCN may play a role in the normal behavior and life of cells, although its detailed role remains unknown. Overexpression of RCN may also play a role in tumorigenesis, tumor invasion, and drug resistance. The new antibody for human RCN is used in the distribution of RCN in normal human organs of fetuses and adults with or without inflammation. Immunohistochemical examination demonstrated a broad distribution of RCN in various organs of fetuses and adults, predominantly in the endocrine and exocrine organs. However, RCN expression was heterogeneous in each constituent cell of some organs. Among non-epithelial organs, vascular endothelial cells, testicular germ cells, neurons, and follicular dendritic cells showed strong staining. Plasma cells were the only RCN-positive cells among hematopoietic and lymphoid cells. In inflammatory conditions, RCN expression was enhanced in both epithelial and non-epithelial cells. Heterogeneous expression of RCN indicates that the amount of RCN needed for cell behavior and life may be variable, depending on each cell type and, therefore, RCN may be helpful in establishing the cell origin of neoplasms in some organs. However, further study is needed to establish the significance of RCN in tumorigenesis and in some peculiar features of neoplasms.


Retina-the Journal of Retinal and Vitreous Diseases | 2015

Subfoveal choroidal thickness changes after intravitreal ranibizumab and photodynamic therapy for retinal angiomatous proliferation.

Ichiro Maruko; Tomohiro Iida; Hiroshi Oyamada; Yukinori Sugano; Masaaki Saito; Tetsuju Sekiryu

Purpose: To evaluate the subfoveal choroidal thickness changes after intravitreal ranibizumab and photodynamic therapy in patients with retinal angiomatous proliferation. Methods: Subfoveal choroidal thickness was retrospectively measured using enhanced depth imaging optical coherence tomography. Results: Thirty-two eyes of 26 patients (average age, 82 years) with newly diagnosed retinal angiomatous proliferation were examined. All eyes were treated with intravitreal ranibizumab and photodynamic therapy. In 14 eyes without recurrence over 6-month follow-up (average, 8.4 months), mean subfoveal choroidal thickness decreased from 198 &mgr;m at baseline to 169 &mgr;m (85.4%) at 3 months and to 173 &mgr;m (87.3%) at 6 months after treatment (P < 0.01 compared with baseline, respectively). In 18 eyes with recurrence over 3-month follow-up, mean subfoveal choroidal thickness decreased from 199 &mgr;m at baseline to 171 &mgr;m (85.9%) at 3 months after treatment and 176 &mgr;m (88.4%) even at recurrence (P < 0.01 compared with baseline, respectively). Conclusion: Subfoveal choroidal thickness after intravitreal ranibizumab and photodynamic therapy for retinal angiomatous proliferation decreased to approximately 85% compared with baseline by 3 months after treatment, and the trend persisted in eyes with or without recurrence during follow-up. This may indicate that choroidal changes are not associated with recurrence in retinal angiomatous proliferation.


Japanese Journal of Ophthalmology | 2012

Demographic features of idiopathic macular telangiectasia in Japanese patients

Ichiro Maruko; Tomohiro Iida; Yukinori Sugano; Akira Ojima; Hiroshi Oyamada; Tetsuju Sekiryu

PurposeIdiopathic macular telangiectasia (MacTel) is classified into aneurysmal telangiectasia (type 1), perifoveal telangiectasia (type 2) and occlusive telangiectasia (type 3). Most instances of telangiectasia in Western countries are type 2. This study reports clinical and demographic features of MacTel in Japanese patients.MethodsNewly diagnosed patients with MacTel were examined retrospectively. All patients underwent fluorescein angiography and optical coherence tomography.ResultsThirty-four eyes of 27 patients with MacTel were included. Twenty eyes of 20 patients (74.1%) had type 1, ten eyes of five patients (18.5%) had type 2, and four eyes of two patients (7.4%) had type 3. Foveal capillary dilatation and microaneurysms were observed in all except for one eye of early stage type 2 MacTel. Optical coherence tomography revealed cystoid macular edema in type 1, temporal foveal thinning and a loss of boundary between the inner and outer segments of photoreceptors in type 2, and thinning of all retinal layers around the fovea in type 3.ConclusionThe most frequent among our patients was aneurysmal MacTel, whereas perifoveal MacTel was not common. Although the clinical characteristics were similar, the most common type was different from that in Western countries.


Clinical Ophthalmology | 2012

Conservative treatment for late-onset bleb leaks after trabeculectomy with mitomycin C in patients with ocular surface disease

Hideto Sagara; Tomohiro Iida; Kimimori Saito; Hiroki Noji; Masashi Ogasawara; Hiroshi Oyamada

Background Sodium hyaluronate and autologous serum eye drops are used to treat ocular surface disease (OSD) and are reported to prevent and treat late-onset bleb leaks following trabeculectomy with mitomycin C. In this study, we evaluated the efficacy of a combination of sodium hyaluronate and autologous serum eye drops and treatment for obstructive meibomian gland dysfunction as a therapy for late-onset bleb leaks after trabeculectomy with mitomycin C. Methods This was a retrospective, interventional, nonsimultaneous study of 12 subjects (12 eyes) of mean age of 64.3 ± 18.3 years with OSD and apparent late-onset bleb leaks following trabeculectomy with mitomycin C between 1998 and 2008. We compared patients diagnosed with leakages before July 2005, who had been treated with separate eye drop solutions containing 0.1% sodium hyaluronate, 50% autologous serum, and 0.3% ofloxacin (sodium hyaluronate and autologous serum group, n = 7), with patients diagnosed from August 2005 to December 2008, who were treated with a combination of eye drops (0.1% sodium hyaluronate, 50% autologous serum, and 0.08% levofloxacin hydrate) and eyelid massage and warm compresses for obstructive meibomian gland dysfunction (combination eye drop group, n = 5). Results Leakage was resolved in one patient (14.3%) in the separately treated sodium hyaluronate and autologous serum eye drop group and in five patients (100%) in the combination eye drop group (P = 0.015). The period after resolution of leakage with conservative treatment was 23 months in the one eye in the sodium hyaluronate and autologous serum group and 36–61 (mean 52.4 ± 10.1) months in the five eyes in the combination eye drop group. Conclusion Late-onset bleb leaks following trabeculectomy with mitomycin C can be treated effectively using a combination of sodium hyaluronate and autologous serum eye drops, eyelid massage, and warm compresses. Furthermore, combining eye drops may improve patient adherence to the drug regimen by decreasing the frequency of administration.


Investigative Ophthalmology & Visual Science | 2015

Prognostic factor of macular edema secondary to branch retinal vein occlusion treated with ranibizumab as needed dosing in Japanese patients.

Akira Ojima; Tetsuju Sekiryu; Hiroshi Oyamada; Masashi Ogasawara; Yasuharu Oguchi


Investigative Ophthalmology & Visual Science | 2013

Swept source optical coherence tomography in eyes with macular hemorrhage

Hiroshi Oyamada; Ichiro Maruko; Yukinori Sugano; Tetsuju Sekiryu; Tomohiro Iida

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Tetsuju Sekiryu

Fukushima Medical University

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Ichiro Maruko

Fukushima Medical University

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Tomohiro Iida

Fukushima Medical University

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Yukinori Sugano

Fukushima Medical University

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Akira Ojima

Fukushima Medical University

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Masashi Ogasawara

Fukushima Medical University

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Ayumi Hozumi

Fukushima Medical University

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Hideto Sagara

Fukushima Medical University

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Hiroki Noji

Fukushima Medical University

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