Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Syunsuke Araki is active.

Publication


Featured researches published by Syunsuke Araki.


Clinical Ophthalmology | 2014

a comparison between amblyopic and fellow eyes in unilateral amblyopia using spectral-domain optical coherence tomography

Syunsuke Araki; Atsushi Miki; Tsutomu Yamashita; Katsutoshi Goto; Kazuko Haruishi; Yoshiaki Ieki; Junichi Kiryu

Purpose To compare the macular retinal thickness and characteristics of optic nerve head (ONH) parameters in amblyopic and fellow eyes in patients with unilateral amblyopia. Patients and methods A total of 21 patients with unilateral amblyopia (14 patients with anisometropic amblyopia, four patients with strabismic amblyopia, and three patients with both) were examined using spectral-domain optical coherence tomography. The mean age of the patients was 8.5±3.5 years. The examined parameters included the mean macular (full, inner, and outer), ganglion cell complex and circumpapillary retinal nerve fiber layer (cpRNFL) thicknesses, and ONH parameters (rim volume, nerve head volume, cup volume, rim area, optic disc area, cup area, and cup-to-disc area ratio). Results The amblyopic eyes were significantly more hyperopic than the fellow eyes (P<0.001). Among the macular retinal thickness parameters, the cpRNFL thickness (P<0.01), macular full retinal thickness (3 mm region) (P<0.01), and macular outer retinal thickness (1 and 3 mm regions) (P<0.05) were significantly thicker in the amblyopic eyes than in the fellow eyes, while the ganglion cell complex thickness, macular full retinal thickness (1 mm region), and macular inner retinal thickness (1 and 3 mm regions) were not significantly different. Among the ONH parameters, the rim area was significantly larger and the cup-to-disc area ratio was smaller in the amblyopic eyes than in the fellow eyes (P<0.05). None of the other ONH parameters were significantly different between the investigated eyes. The differences in the cpRNFL thickness and macular outer retinal thickness in the 1 mm region were significantly correlated with the difference in axial length (P<0.05, r=−0.48; P<0.01, r=−0.59, respectively) and refractive error (P<0.05, r=0.50; P<0.01, r=0.60, respectively). The other parameters were not significantly related to the difference in axial length, refractive error, or best corrected visual acuity. Conclusion We found significant differences in some of the morphological measurements between amblyopic and fellow eyes that appear to be independent of abnormalities in the visual cortex.


Neuro-Ophthalmology | 2016

Time Course of Macular and Peripapillary Inner Retinal Thickness in Non-arteritic Anterior Ischaemic Optic Neuropathy Using Spectral-Domain Optical Coherence Tomography

Katsutoshi Goto; Atsushi Miki; Syunsuke Araki; Kenichi Mizukawa; Masaki Nakagawa; Go Takizawa; Yoshiaki Ieki; Junichi Kiryu

ABSTRACT To report a time course of the ganglion cell complex (GCC) and circumpapillary retinal nerve fibre layer (cpRNFL) thicknesses using spectral-domain optical coherence tomography in patients with non-arteritic anterior ischaemic optic neuropathy (NAION), five patients with unilateral NAION were studied (the average age of 66.8 ± 7.8 years old). Forty-one age-matched normal controls were also enrolled. The GCC and cpRNFL thicknesses were measured at the initial visit and at 1, 3, 6, and 12 months using RTVue-100. The GCC thickness and the cpRNFL thickness of the patients were compared with those of the normal controls. The GCC thickness in the NAION patients was 96.49 μm at the initial visit, 84.28 μm at 1 month, 74.26 μm at 3 months, 71.23 μm at 6 months, and 69.51 μm at 12 months. The values at 1, 3, 6, and 12 months were significantly reduced (p < 0.01). The cpRNFL thickness at the initial visit was significantly increased, whereas the values at 6 and 12 months were significantly reduced (p < 0.01). The GCC thickness is more useful for the detection of retinal ganglion cell loss at an early stage than the cpRNFL thickness, because the GCC thickness is unaffected by optic disc swelling at the initial visit, unlike the cpRNFL thickness.


Journal of Ophthalmology | 2016

Retinal Ganglion Cell Atrophy in Homonymous Hemianopia due to Acquired Occipital Lesions Observed Using Cirrus High-Definition-OCT

Tsutomu Yamashita; Atsushi Miki; Katsutoshi Goto; Syunsuke Araki; Go Takizawa; Yoshiaki Ieki; Junichi Kiryu; Akio Tabuchi; Yasuyuki Iguchi; Kazumi Kimura; Yoshiki Yagita

Purpose. To report a reduction in macular ganglion cell layer and inner plexiform layer (GCL+IPL) thickness and circumpapillary retinal nerve fiber layer (cpRNFL) thickness using spectral-domain optical coherence tomography in patients with homonymous hemianopia due to posterior cerebral artery (PCA) stroke. Methods. Seven patients with PCA stroke were examined using Cirrus high-definition-OCT. The GCL+IPL thicknesses were divided into the hemianopic and unaffected sides. The relationship between the time after stroke and the GCL+IPL thicknesses in the hemianopic side was evaluated. Results. The average thicknesses of the GCL+IPL were 64.6 and 82.0 μm on the hemianopic and unaffected sides, respectively, and the measurement was significantly thinner on the former side (p = 0.018). A regression analysis revealed a negative linear relationship (R 2 = 0.574, p = 0.049) between the time after stoke and the GCL+IPL thicknesses on the hemianopic side. The supratemporal and inferotemporal cpRNFL thicknesses in the eyes ipsilateral to the stroke showed a significant reduction. Conclusion. Our findings confirmed our previous observations that the degeneration of retinal ganglion cells can occur after PCA stroke. GCL+IPL thinning was demonstrated in the hemiretinae corresponding to the affected hemifields. Also, it is suggested that the retinal changes observed are progressive.


Clinical Ophthalmology | 2015

Association between a relative afferent pupillary defect using pupillography and inner retinal atrophy in optic nerve disease

Go Takizawa; Atsushi Miki; Fumiatsu Maeda; Katsutoshi Goto; Syunsuke Araki; Yoshiaki Ieki; Junichi Kiryu; Kiyoshi Yaoeda

Purpose The aim of this study was to compare the asymmetrical light reflex of the control subjects and patients with optic nerve disease and to evaluate the relationships among the relative afferent pupillary defect (RAPD), visual acuity (VA), central critical fusion frequency (CFF), ganglion cell complex thickness (GCCT), and circumpapillary retinal nerve fiber layer thickness (cpRNFLT) using spectral-domain optical coherence tomography. Materials and methods Using a pupillography device, the RAPD scores from 15 patients with unilateral optic nerve disease and 35 control subjects were compared. The diagnostic accuracy of the RAPD amplitude and latency scores was compared using the area under the receiver operating characteristic curve. Thereafter, we assessed the relationships among the RAPD scores, VA, central CFF, GCCT, and cpRNFLT. Results The average RAPD amplitude score in patients with optic nerve disease was significantly higher than that of the control subjects (P<0.001). The average RAPD latency score in patients with optic nerve disease was significantly higher than that of the control subjects (P=0.001). The area under the receiver operating characteristic curve for the RAPD amplitude score was significantly higher than that for the latency score (P=0.010). The correlation coefficients for the RAPD amplitude and latency scores were 0.847 (P<0.001) and 0.874 (P<0.001) for VA, −0.868 (P<0.001) and −0.896 (P<0.001) for central CFF, −0.593 (P=0.020) and −0.540 (P=0.038) for GCCT, and −0.267 (P=0.337) and −0.228 (P=0.413) for cpRNFLT, respectively. Conclusion Our results suggest that pupillography is useful for detecting optic nerve disease.


Journal of Ophthalmology | 2017

Quantitative Analysis of Macular Inner Retinal Layer Using Swept-Source Optical Coherence Tomography in Patients with Optic Tract Syndrome

Katsutoshi Goto; Atsushi Miki; Tsutomu Yamashita; Syunsuke Araki; Go Takizawa; Kenichi Mizukawa; Yoshiaki Ieki; Junichi Kiryu

Objective To evaluate macular inner retinal layers using swept-source optical coherence tomography (SS-OCT) in patients with homonymous hemianopia due to optic tract syndrome (OTS). Methods Sixteen eyes of 8 patients with OTS were studied. The macular retinal nerve fiber layer (mRNFL), ganglion cell layer and inner plexiform layer (GCL + IPL), and mRNFL and GCL + IPL (GCC) were measured by SS-OCT (DRI OCT-1 Atlantis®).The scanned area was divided into eight regions and two hemiretinae. Each retinal thickness of the OTS group was compared with that of the 25 control subjects. Results The GCC thickness in the ipsilateral eyes was significantly reduced in all regions, although predominant thinning of the GCC in the contralateral eyes was found in the nasal region. The GCC + IPL thickness was preferentially reduced at the temporal regions in the ipsilateral eyes and at the nasal regions in the contralateral eyes. The reduction rate of the GCL + IPL thickness was 29.6% at the temporal hemiretina in the ipsilateral eyes and 35.2% at the nasal hemiretina in the contralateral eyes. Conclusion We found preferential loss of the GCC + IPL thickness corresponding to the hemifield defects in each eye. Quantitative analysis by SS-OCT is capable of detecting the characteristic RGC loss due to OTS.


BMC Ophthalmology | 2017

Macular retinal and choroidal thickness in unilateral amblyopia using swept-source optical coherence tomography

Syunsuke Araki; Atsushi Miki; Katsutoshi Goto; Tsutomu Yamashita; Go Takizawa; Kazuko Haruishi; Yoshiaki Ieki; Junichi Kiryu; Kiyoshi Yaoeda

BackgroundTo investigate macular retinal and choroidal thickness in amblyopic eyes compared to that in fellow and normal eyes using swept-source optical coherence tomography (SS-OCT).MethodsThis study examined 31 patients with hyperopic anisometropic amblyopia (6.9 ± 3.8 years, mean ± standard deviation), 15 patients with strabismic amblyopia without anisometropia (7.9 ± 4.2 years), and 24 age-matched controls (7.8 ± 3.3 years). Retinal and choroidal thickness was measured by 3D scans using SS-OCT. A 6-mm area around the fovea was automatically analyzed using the Early Treatment Diabetic Retinopathy Study map. The thickness from SS-OCT was corrected for magnification error using individual axial length, spherical refraction, cylinder refraction, and corneal radius. Retinal thickness was divided into the macular retinal nerve fiber layer (mRNFL), ganglion cell layer + inner plexiform layer (GCL+IPL), ganglion cell complex (GCC), and the inner limiting membrane to the retinal pigment epithelium (ILM-RPE) thickness. Retinal and choroidal thickness was compared among amblyopic, fellow, and normal eyes.ResultsIn both amblyopia groups, there was no significant difference in the mRNFL, GCL+IPL, and GCC thicknesses among the amblyopic, fellow, and control eyes. In the anisometropic amblyopia group, choroidal thickness (subfovea, center 1 mm, nasal and inferior of the inner ring, nasal of the outer ring, and center 6 mm) of amblyopic eyes were significantly greater than that of fellow and normal eyes. In contrast, none of the choroidal thicknesses were significantly different among the investigated eyes in the strabismic amblyopia group.ConclusionsWe found no significant difference in inner retinal thickness in patients with unilateral amblyopia. Although there were significant differences in choroidal thickness with hyperopic anisometropic amblyopia, there was no significant difference for the strabismic amblyopia. The discrepancy in choroidal thickness between the two types of amblyopia may be due to both differences in ocular size and underlying mechanism.


Neuro-Ophthalmology | 2018

Relative Afferent Pupillary Defects in Homonymous Visual Field Defects Caused by Stroke of the Occipital Lobe Using Pupillometer

Go Takizawa; Atsushi Miki; Fumiatsu Maeda; Katsutoshi Goto; Syunsuke Araki; Tsutomu Yamashita; Yoshiaki Ieki; Junichi Kiryu; Kiyoshi Yaoeda

ABSTRACT Relative afferent pupillary defects (RAPD) may be detected in patients with occipital lobe lesions. However, no previous report has used an objective technique to record the abnormal pupillary light reflex in such cases. Therefore, we measured the pupillary light reflex objectively in 15 patients with homonymous visual field defects (HVFD) due to occipital stroke using a new pupillometer. This study detected significantly smaller and slower pupillary light reflexes in the contralateral eyes than in the other eyes, which is equivalent to the presence of RAPD in patients with HVFDs caused by retrogeniculate lesions using an objective technique. Our results confirmed those of the previous reports using the swinging flashlight test more objectively.


Acta Ophthalmologica | 2018

Preferential atrophy of the central retinal ganglion cells in homonymous hemianopia due to acquired retrogeniculate lesions demonstrated using swept-source optical coherence tomography

Tsutomu Yamashita; Atsushi Miki; Katsutoshi Goto; Syunsuke Araki; Go Takizawa; Yoshiaki Ieki; Junichi Kiryu; Akio Tabuchi; Yasuyuki Iguchi; Kazumi Kimura; Yoshiki Yagita

Department of Sensory Science, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, Kurashiki, Okayama, Japan; Department of Ophthalmology, Kawasaki Medical School, Okayama, Japan; Department of Neurology, The Jikei University School of Medicine, Tokyo, Japan; Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan; Department of Stroke Medicine, Kawasaki Medical School, Okayama, Japan


Graefes Archive for Clinical and Experimental Ophthalmology | 2016

Sectoral analysis of the retinal nerve fiber layer thinning and its association with visual field loss in homonymous hemianopia caused by post-geniculate lesions using spectral-domain optical coherence tomography

Katsutoshi Goto; Atsushi Miki; Tsutomu Yamashita; Syunsuke Araki; Go Takizawa; Masaki Nakagawa; Yoshiaki Ieki; Junichi Kiryu


Journal of Neuro-ophthalmology | 2018

Retinal Nerve Fiber Layer and Peripapillary Capillary Density Reduction Detected Using Optical Coherence Tomography Enface Images and Angiography in Optic Tract Syndrome

Katsutoshi Goto; Atsushi Miki; Tsutomu Yamashita; Syunsuke Araki; Go Takizawa; Yoshiaki Ieki; Junichi Kiryu

Collaboration


Dive into the Syunsuke Araki's collaboration.

Top Co-Authors

Avatar

Atsushi Miki

Kawasaki Medical School

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Go Takizawa

Kawasaki Medical School

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Akio Tabuchi

Kawasaki University of Medical Welfare

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge