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Dive into the research topics where Masayasu Kitahashi is active.

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Featured researches published by Masayasu Kitahashi.


British Journal of Ophthalmology | 2010

Two-year comparison of photodynamic therapy and intravitreal bevacizumab for treatment of myopic choroidal neovascularisation

Takayuki Baba; Masayasu Kitahashi; Kyoko Okada; Yoshinori Mitamura; Shuichi Yamamoto

Aim To compare the long-term outcome of photodynamic therapy (PDT) with that of intravitreal bevacizumab (IVB) for myopic choroidal neovascularisations (mCNVs). Methods 24 eyes were selected from 40 consecutive patients with mCNV, and the patients were divided into Group A, consisting of 12 eyes treated by PDT, and Group B, consisting of 12 eyes treated by 1.25 mg IVB. The age and best-corrected visual acuity (BCVA) were matched between the two groups. The BCVA, size of the chorioretinal atrophy surrounding the CNV (CRA), central foveal thickness (CFT) and CNV thickness were determined before and at 12 and 24 months after the treatment. Results The BCVA did not change after PDT but was significantly improved from 0.75±0.25 to 0.49±0.42 logMAR units at 12 months and to 0.50±0.38 logMAR units at 24 months after IVB. The CFT were significantly reduced in both groups at 12 and 24 months. The CRAs were larger in group A than in group B at 12 and 24 months, and their sizes were correlated with the BCVA. Conclusion At 24 months, IVB is more effective than PDT in treating mCNV. The enlargement of the CRA might be related to the incomplete visual recovery after PDT.


American Journal of Ophthalmology | 2011

Foveal microstructure on spectral-domain optical coherence tomographic images and visual function after macular hole surgery.

Emi Ooka; Yoshinori Mitamura; Takayuki Baba; Masayasu Kitahashi; Toshiyuki Oshitari; Shuichi Yamamoto

PURPOSE To determine the correlation between the recovery of foveal microstructure and the visual acuity or the foveal sensitivity after idiopathic macular hole (MH) closure. DESIGN Prospective, consecutive, observational case series. METHODS We studied 43 eyes of 43 patients before and 1, 3, and 6 months after MH surgery. The best-corrected visual acuity (BCVA), the foveal sensitivity measured by MP1 microperimetry, and the photoreceptor inner and outer segment (IS/OS) junction and the external limiting membrane (ELM) determined by spectral-domain optical coherence tomography were investigated. RESULTS Preoperatively, the lengths of the IS/OS junction defect and the ELM defect were significantly correlated with only the foveal sensitivity (P<.0001). At all postoperative times, the lengths of both the IS/OS and ELM defects were significantly correlated with both the BCVA and the foveal sensitivity (P<.05 for all). The preoperative lengths of both the IS/OS and ELM defects were significantly correlated with the foveal sensitivity at 6 months after surgery (P=.0022, P=.0031, respectively). The IS/OS junction defect was significantly correlated with the ELM defect at all times (P<.0001 for all). No restoration of the IS/OS junction was observed in eyes without the ELM restoration. CONCLUSIONS The restoration of the ELM is closely associated with that of the IS/OS junction. The preoperative IS/OS or ELM defect was associated with the postoperative foveal sensitivity. The restoration of not only the IS/OS junction but also the ELM may reflect the morphologic and functional recovery of the foveal photoreceptors in surgically closed MHs.


Ophthalmologica | 2012

Two-Year Course of Subfoveal Pigment Epithelial Detachment in Eyes with Age-Related Macular Degeneration and Visual Acuity Better than 20/40

Takayuki Baba; Masayasu Kitahashi; Toshiyuki Oshitari; Shuichi Yamamoto

Purpose: To investigate the course of subfoveal pigment epithelial detachments (PEDs) in eyes with age-related macular degeneration (AMD) and best-corrected visual acuity (BCVA) ≥20/40. Methods: Thirty-seven eyes of 35 patients with a subfoveal PED were divided into an avascular PED group (n = 11), a vascularized PED group due to polypoidal choroidal vasculopathy (PCV, n = 14) and an occult choroidal neovascularization (CNV) group (n = 12). Intravitreal bevacizumab or ranibizumab was given as needed. The BCVA, central foveal thickness, PED thickness, and lesion size were measured at baseline and at 2 years after the initial examination. Results: The BCVA did not change significantly in the avascular group, decreased from 0.06 ± 0.11 to 0.23 ± 0.15 logMAR units in the PCV group and from 0.12 ± 0.12 to 0.71 ± 0.70 logMAR units in the CNV group. At 2 years, the central foveal and PED thicknesses were not significantly different among the 3 groups, and the lesion was significantly larger in the PCV and CNV groups than in the avascular group. Conclusions: The vascularized PED cases had a poorer visual outcome than avascular PEDs with anti-VEGF drugs at the 2-year follow-up.


Indian Journal of Ophthalmology | 2010

Comparison of intravitreal bevacizumab to photodynamic therapy for polypoidal choroidal vasculopathy: short-term results.

Yoshinori Mitamura; Masayasu Kitahashi; Shuichi Yamamoto

Aims: To compare the short-term therapeutic effects of intravitreal bevacizumab (IVB) to those of photodynamic therapy (PDT) for polypoidal choroidal vasculopathy (PCV). Materials and Methods: Retrospective interventional case study. Eighty-nine eyes of 89 patients with symptomatic PCV were treated by IVB or PDT. Eighteen eyes were treated with a single injection of IVB (s-IVB group), 22 eyes with three consecutive monthly IVB injections (m-IVB group), and 49 eyes with PDT alone (PDT group). The best-corrected visual acuity (BCVA) and OCT-determined central foveal thickness (CFT) were evaluated before, and one and three months after the treatment. For statistical analyses, one-factor ANOVA and Chi-square test were used. Results: The differences in the BCVA and CFT among the three groups at the baseline were not significant (P=0.992, P=0.981, respectively). Three months after the treatment, the BCVA improved by >0.2 logMAR units in two out of 18 eyes (11%) in the s-IVB group, three out of 22 eyes (14%) in the m-IVB group, and 15 out of 49 eyes (31%) in the PDT group (P=0.124). A decrease in the CFT by >20% was achieved in six out of 18 eyes in the s-IVB group, ten eyes (46%) in the m-IVB group, and 35 eyes (71%) in the PDT group (P=0.009). The resolution of polyps was achieved in three out of 18 eyes in the s-IVB group, one eye (5%) in the m-IVB group and 35 eyes (71%) in the PDT group (P<0.001). Conclusion: The better short-term therapeutic outcomes in the PDT group than in the s-IVB and m-IVB groups indicate that PDT may be more effective than IVB in short term after treatment for PCV.


Clinical Ophthalmology | 2009

Changes in visual function and thickness of macula after photodynamic therapy for age-related macular degeneration

Kyoko Okada; Masayasu Kitahashi; Takayuki Baba; Yoshinori Mitamura; Shuichi Yamamoto

Purpose To determine the correlation between the changes in the central retinal sensitivity and the changes in the foveal thickness (FT) after photodynamic therapy (PDT) for age-related macular degeneration (AMD). Methods Nineteen eyes of 19 patients with choroidal neovasularizations (CNVs) secondary to AMD were studied. The pretreatment values of the central retinal sensitivity determined by Micro Perimeter 1 (MP1; Nidek Technologies), best-corrected visual acuity (BCVA), and optical coherence tomography (OCT)-determined FT were compared to the postoperative values at three and six months after PDT. Results At six months, the retinal sensitivity within the central 10° was significantly improved (P = 0.02) and the FT was significantly thinner (P = 0.016). The BCVA, however, did not change significantly (P = 0.80). The changes in the retinal sensitivities were significantly correlated with the changes in the decrease in the FT (r = − 0.59, P = 0.012 within the central 10°) at six months after PDT. Conclusion Significant improvements in retinal sensitivities within the central 10° and a decrease in FT were observed even though the BCVA was not significantly improved. The measurement of retinal sensitivity by MP1 may be a better method to assess central visual function than the conventional visual acuity after PDT.


Case Reports in Ophthalmology | 2011

Subretinal Hemorrhage after Photodynamic Therapy for Juxtapapillary Retinal Capillary Hemangioma

Takayuki Baba; Masayasu Kitahashi; Toshiyuki Oshitari; Shuichi Yamamoto

A 75-year-old Japanese woman presented with a juxtapapillary retinal capillary hemangioma (RCH) in her left eye. Twelve months after the initial examination, the size of the hemangioma had increased and the exudation from the RCH involved the macula. Her best-corrected visual acuity (BCVA) had decreased from 0.8 to 0.3. A total of five intravitreal injections of bevacizumab (IVB; 1.25 mg) was given but the RCH did not respond. A photodynamic therapy (PDT) was done using multiple laser spots to avoid damaging the optic nerve head. After the first PDT, the subfoveal fluid was reduced but not completely gone. One week after the second PDT, a massive subretinal hemorrhage developed. The subretinal hemorrhage was successfully displaced by injecting intraocular sulfur hexafluoride (SF6) gas. At the 3-year follow-up examination, no subretinal hemorrhage or fluid was observed at the macula and the BCVA remained at 0.05. Our case was resistant to the combination of anti-vascular endothelial growth factor (VEGF) and PDT and had a rare massive subretinal hemorrhage. A further collection of RCH cases treated with anti-VEGF and PDT that would justify this treatment is necessary.


Clinical Ophthalmology | 2014

One-year results of intravitreal ranibizumab combined with reduced-fluence photodynamic therapy for polypoidal choroidal vasculopathy.

Madoka Sakurai; Takayuki Baba; Masayasu Kitahashi; Hirotaka Yokouchi; Guzel Bikbova; Toshiyuki Oshitari; Shuichi Yamamoto

Purpose To compare the 1-year results of intravitreal ranibizumab combined with reduced-fluence photodynamic therapy (RF-PDT) to intravitreal ranibizumab (IVR) alone for eyes with polypoidal choroidal vasculopathy (PCV). Methods We reviewed the medical records from 47 consecutive patients with PCV (47 naïve eyes). Seventeen eyes from 17 patients had one IVR treatment combined with RF-PDT followed by two additional IVR treatments (combined group), and 30 eyes from 30 patients were treated with 3 monthly IVR treatments (IVR group). All eyes had a follow-up period of at least 12 months. Results At 12 months, the mean logarithm of the minimal angle of resolution (logMAR) best-corrected visual acuity (BCVA) significantly improved from 0.55 to 0.38 logMAR units in the combined group (P=0.041) but did not change significantly in the IVR group (P=0.371). The central foveal thickness (CFT) was significantly thinner in both groups at 6 months (P<0.01). Additional IVR injections were required less frequently in the combined group (n=3; 17%) than in the IVR group (n=16; 53%) during the 12 month follow-up (P=0.029). Conclusion The IVR and RF-PDT combination led to significant BCVA improvements and required fewer additional IVR treatments for at least 12 months in eyes with PCV.


British Journal of Ophthalmology | 2016

Correlation between peripapillary retinal thickness and serum level of vascular endothelial growth factor in patients with POEMS syndrome

Hirotaka Yokouchi; Takayuki Baba; Sonoko Misawa; Setsu Sawai; Masayasu Kitahashi; Toshiyuki Oshitari; Satoshi Kuwabara; Shuichi Yamamoto

Aims To determine whether there is a significant correlation between the peripapillary retinal thickness (pRT) and the serum level of vascular endothelial growth factor (VEGF) in patients with polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and skin changes (POEMS) syndrome. Methods This was a cross-sectional, observational case series. We studied 34 eyes of 17 treatment-naïve patients with POEMS syndrome whose intracranial pressure was within the normal range. The spectral-domain optical coherence tomographic (SD-OCT) examinations consisted of circle scans of 3.45 mm diameter around the optic disc. The pRT was automatically measured in the SD-OCT images and was used for the statistical analysis. The serum level of VEGF was measured by ELISAs, and the correlation between the pRT and the serum level of VEGF was determined. Multivariable logistic regression analyses were used to identify independent factors that were correlated with the pRT. Results There was a significant positive correlation between the serum levels of VEGF and the average pRT of the two eyes of each patient (r=0.81, p<0.0001). There was a significant correlation between the pRT of the right and left eyes with an intraclass correlation coefficient of 0.839. Multiple regression analysis showed that the serum levels of VEGF were independent contributors to the pRT (standard regression coefficient=0.59, p=0.012). Conclusions The significant correlation between the pRT and the serum level of VEGF suggests that the higher serum level of VEGF might be associated with the development of the optic disc oedema in patients with POEMS syndrome.


Clinical Ophthalmology | 2014

Pneumatic displacement with intravitreal bevacizumab for massive submacular hemorrhage due to polypoidal choroidal vasculopathy

Masayasu Kitahashi; Takayuki Baba; Madoka Sakurai; Hirotaka Yokouchi; Yoshinori Mitamura; Shuichi Yamamoto

Background The purpose of this study was to compare the effectiveness of pneumatic displacement combined with intravitreal bevacizumab (IVB) with that of pneumatic displacement (PD) alone to treat massive submacular hemorrhage (SMH) secondary to polypoidal choroidal vasculopathy (PCV). Methods Thirty-two eyes of 32 patients with massive SMH secondary to PCV were studied. Twenty-two eyes were treated with a combination of PD and 1.25 mg of intravitreal bevacizumab (PD + IVB group), and ten eyes with pneumatic displacement alone (PD group). Results Pretreatment, the differences in best-corrected visual acuity and size of the SMH between the two groups were not significant (P=0.59 and P=0.72, respectively). Complete displacement of the hemorrhage from under the fovea was achieved in 19 of 22 eyes (86.4%) in the PD + IVB group and in five of ten eyes (50%) in the PD group. The best-corrected visual acuity in the PD + IVB group was significantly better than that in the PD group at one, 3, and 6 months after treatment (P<0.001, P<0.001, and P<0.001, respectively). Improvement in best-corrected visual acuity by >0.3 logMAR units was obtained in 18 eyes (81.8%) in the PD + IVB group and two eyes (20%) in the PD group (P<0.001). The number of eyes that required additional treatments was significantly fewer in the PD + IVB group than in the PD group (P=0.0001). Conclusion The combination of PD and IVB may be a better therapeutic procedure for eyes with massive SMH due to PCV in the short term because of the better visual outcome and less need for additional treatments.


British Journal of Ophthalmology | 2017

Changes in subfoveal choroidal thickness and reduction of serum levels of vascular endothelial growth factor in patients with POEMS syndrome

Hirotaka Yokouchi; Takayuki Baba; Sonoko Misawa; Masayasu Kitahashi; Toshiyuki Oshitari; Satoshi Kuwabara; Shuichi Yamamoto

Aims To determine the changes in the subfoveal choroidal thickness (CT), the foveal thickness (FT) and the serum level of vascular endothelial growth factor (VEGF) after thalidomide treatment in patients with polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and skin changes (POEMS) syndrome. Methods We studied 13 left eyes of 13 treatment-naïve patients with POEMS syndrome. The subfoveal CT and FT were determined by enhanced depth imaging optical coherence tomography, and the serum level of VEGF was determined by ELISA at the baseline and at 6 months after thalidomide treatment. The correlations in the serum level of VEGF and the subfoveal CT or the FT at the baseline and at 6 months after treatment were determined. Results Together with the reduction in the serum level of VEGF, the subfoveal CT was also reduced significantly from 439.1±66.5 µm at the baseline to 307.2±75.4 µm at 6 months (p=0.001). The mean FT at the baseline was 236.4±30.7 µm which did not change significantly at 6 months at 228.1±33.1 µm (p>0.05). The change in the subfoveal CT was significantly and linearly correlated with the change in the serum level of VEGF at 6 months after treatment (r=0.67, p=0.011). Conclusions The significant correlation between the CT and the serum level of VEGF may offer clues on the pathogenesis of ocular diseases of POEMS syndrome and on the role of serum VEGF on the choroid.

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