Shuichi Yamamoto

Correlation between visual function and photoreceptor inner/outer segment junction in patients with retinitis pigmentosa

PurposeTo determine whether a significant correlation exists between the visual acuity or foveal thickness and the status of the inner and outer segment junction (IS/OS) of the photoreceptor in patients with retinitis pigmentosa (RP).MethodsThree hundred eyes of 163 patients with RP were examined with the optical coherence tomography (OCT). The IS/OS appeared as a distinct, highly reflective line just vitread of the retinal pigment epithelium in the OCT3 images. The IS/OS line was graded into three groups. The correlations between the grade of the IS/OS and age, best-corrected visual acuity (BCVA), and central foveal thickness (CFT) were determined.ResultsGrade 1 included 93 eyes (31.0%) in which an IS/OS line was not seen, Grade 2 included 67 eyes (22.3%) with an abnormal IS/OS, and Grade 3 included 140 eyes (46.7%) with a normal IS/OS. The correlation between the IS/OS grade and age was not significant (P=0.5536). The IS/OS grade was significantly correlated with BCVA and CFT (both P<0.0001). The BCVA was significantly better in Grade 3 eyes than Grades 1 and 2 (both P<0.0001). The CFT was significantly thinner in Grade 1 eyes than in Grades 2 and 3 (both P<0.0001). In Grade 3, the mean length of the IS/OS was 2.51±1.42 mm (±SD). The length of the IS/OS was significantly correlated with the BCVA (P<0.0001, r=−0.375).ConclusionsThe presence of the IS/OS was associated with better visual acuity and thicker fovea in RP patients. The absence of an IS/OS may reflect a foveal dysfunction in RP patients.

Corneal Changes in Diabetes Mellitus

Diabetes mellitus is a major disease worldwide, and the prevalence of diabetes has risen significantly in the past several decades. Although one of the major complications of diabetic eyes is diabetic retinopathy (DR), corneal diseases can not only develop in diabetic patients but are also difficult to manage. Diabetic neurotrophic keratopathy is a component of diabetic polyneuropathy and is recognized to be the cause of the morbidity of the cornea in diabetic patients. In addition, corneal endothelial cell damage can cause disturbances in the management of proliferative DR before and after surgeries because of endothelial decompensation with bullous keratopathy. However, there have been only a limited number of studies that have focused on the importance of corneal diseases in diabetic patients. This review describes the pathophysiological roles of different factors that have been found to be causative factors of diabetic corneal keratopathy and endothelial cell dysfunction in diabetic patients. In addition, the clinical features of the corneal changes in diabetic patients and recent studies related to the development of therapies for the management of corneal diseases are presented.

Reduction of thickness of ganglion cell complex after internal limiting membrane peeling during vitrectomy for idiopathic macular hole

Background/aimThe aim of this study is to report a reduction in the thickness of the ganglion cell complex (GCC) after vitrectomy with internal limiting membrane (ILM) peeling in eyes with idiopathic macular hole (MH).MethodsTwenty-eight consecutive eyes with an idiopathic MH treated by vitrectomy with ILM peeling were studied. All eyes had an intravitreal injection of indocyanine green to make the ILM more visible. The best-corrected visual acuity (BCVA), GCC thickness measured by spectral domain optical coherence tomography, and retinal sensitivity measured by microperimetry were determined before and at 3 and 6 months after the vitrectomy.ResultsThe MH in all eyes was closed after the initial surgery. The BCVA was significantly improved at 3 and 6 months (P<0.001 and P<0.001, respectively). The thickness of the GCC was significantly reduced at 3 and 6 months postoperatively (P<0.001 and P<0.001, respectively). The GCC thickness was significantly correlated with the retinal sensitivity in the central 10 degrees at 6 months (r=0.55, P=0.004).ConclusionA reduction of the GCC thickness was observed after vitrectomy with ILM peeling for idiopathic MH.

Comparison of Vitrectomy with Brilliant Blue G or Indocyanine Green on Retinal Microstructure and Function of Eyes with Macular Hole

PURPOSE To evaluate the microstructure of the inner and outer retina and the visual function after macular hole (MH) surgery using brilliant blue G (BBG) or indocyanine green (ICG) to make the internal limiting membrane (ILM) more visible. DESIGN Comparative, retrospective, interventional case series. PARTICIPANTS Sixty-three eyes of 63 consecutive cases with MH were studied. Thirty-five eyes of 35 cases were treated with BBG between January and August 2011. Twenty-eight eyes of 28 MH cases were treated with ICG from April 2009 through April 2010. METHODS Vitrectomy was performed with a 23-gauge system and 0.25 mg/ml BBG or with 0.125% ICG. MAIN OUTCOME MEASURES The best-corrected visual acuity (BCVA) and the microperimetry-determined retinal sensitivity were measured at baseline and at 3 and 6 months after surgery. The length of the defect of the photoreceptor inner segment/outer segment (IS/OS) junction and external limiting membrane (ELM), the central foveal thickness (CFT), and the thickness of the ganglion cell complex (GCC) were measured in the spectral-domain optical coherence tomographic images. RESULTS The average BCVA was significantly better in the BBG group than in the ICG group at 3 months (P = 0.021) and 6 months (P = 0.045) after surgery. The mean retinal sensitivity in the BBG group was improved significantly in the central 2° at 3 and 6 months (P = 0.001 and P = 0.030, respectively), but was not significantly improved in the adjacent 10°. The length of IS/OS junction defect was significantly shorter in the BBG group at 3 months (P = 0.048), but was not significantly different at 6 months (P = 0.135). The length of ELM defect and the GCC thickness were not significantly different between the 2 groups at 3 and 6 months. The CFT was significantly thinner in the ICG group than in the BBG group at 3 and 6 months (P = 0.013 and P = 0.001, respectively). CONCLUSIONS The postoperative BCVA and retinal sensitivity in the central 2° were better in eyes after BBG-assisted vitrectomy. The restoration of IS/OS junction was faster in the BBG group, and the CFT was significantly thinner in eyes after ICG. Brilliant blue G may be a better agent than ICG to make the ILM more visible. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Functional and morphological changes of macula after subthreshold micropulse diode laser photocoagulation for diabetic macular oedema

PurposeTo examine the early changes of retinal sensitivity by fundus-related microperimetry after subthreshold micropulse diode laser photocoagulation (SMDLP) for diabetic macular oedema (DMO).MethodsTwenty-eight eyes of 28 patients with diffuse DMO were treated with SMDLP. The mean retinal sensitivity within the central 10 degrees measured with a fundus-related microperimeter, MP1, best corrected visual acuity (BCVA) in logarithm of minimum angle of resolution units, and optical coherence tomography-determined foveal thickness (FT) were examined before and 3 months after SMDLP. The pretreatment values of the retinal sensitivity, FT, BCVA, and funduscopic findings were compared with the corresponding values at 3 months after SMDLP.ResultsAt 3 months, the BCVA was significantly improved (P=0.03), and the FT was significantly reduced (P=0.0043). The mean retinal sensitivity within the central 10 degree, however, did not change significantly (P=0.70). The correlation between the changes in the retinal sensitivities and the decrease in the FT was not significant. The correlation between the changes in the retinal sensitivities and the BCVA was also not significant.ConclusionsSignificant improvements in retinal sensitivities within the central 10 degrees were not observed even though the decrease in FT and the improvement of BCVA were significant. On account of this difference of changes in retinal sensitivity and BCVA, the combination of retinal sensitivity by MP1 and BCVA may be beneficial in assessing the visual function from various angles after SMDLP for eyes with DMO.

Effect of neurotrophic factors on neuronal apoptosis and neurite regeneration in cultured rat retinas exposed to high glucose

The purpose of this study was to investigate the effect of brain-derived neurotrophic factor (BDNF), neurotrophin-4 (NT-4), and citicoline on neuronal apoptosis and neurite regeneration in cultured rat retinas exposed to high glucose (HG). The retinas of six adult Sprague-Dawley rats were studied. After the rats were euthanized, the retinas were isolated and cultured in serum-free medium. One group of explants was cultured in normal glucose (NG) and another group in HG medium (HGM). BDNF, NT-4, or citicoline were added to the HGM. After 7 days, the number of regenerating neurites was counted. Then, the explants were fixed, cryosectioned, and stained by TdT-dUTP terminal nick-end labeling (TUNEL), and also immunostained for the active-forms of caspase-3 and -9. The numbers of TUNEL-positive and caspase-3 and -9-immunopositive cells in the ganglion cell layer (GCL) were significantly higher, and the number of regenerating neurites was significantly lower in retinas cultured in HGM than in NG medium. Retinas incubated in HGM supplemented with BDNF, NT-4, or citicoline had significantly lower numbers of TUNEL-positive and caspase-3 and -9-immunopositive cells in the GCL, and the numbers of regenerating neurites were significantly higher than in HGM without these factors. We conclude that the increase in the number of apoptotic cells and decrease the number of regenerating neurites in the HGM indicate that HG is toxic to RGCs. The decrease in the number of apoptotic cells in the HGM containing BDNF, NT-4, or citicoline is correlated with the suppression of the caspase-9 and -3 activities.

Relationship between peripheral visual field loss and vision-related quality of life in patients with retinitis pigmentosa.

PurposeTo determine the vision-related quality of life (VRQOL) with the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25) in patients with retinitis pigmentosa (RP), and to examine the relationship between VRQOL and peripheral visual field defects.DesignProspective study.MethodsThe Japanese version of the NEI VFQ-25 was used to study 40 patients with typical RP whose visual acuity was ⩾0.7 (better than 0.15 in log MAR). For control, 40 volunteers with normal vision were studied in the same way. The peripheral visual field was evaluated by Goldmanns perimetry, and the degree of field loss was classified into seven grades. The correlation between the mean of the total composite score of the NEI VFQ-25 and the degree of the visual field loss was determined.ResultsThe mean NEI VFQ-25 score was 68.4 in RP patients and 90.1 in normal controls. This difference was highly significant (P=0.00004). Among RP patients, there was a significant negative correlation between the mean NEI VFQ-25 score and the degree of visual field loss (r=−0.519, P=0.0006).ConclusionThe significant correlation between the peripheral visual field loss and VRQOL score obtained with the NEI VFQ-25, indicates that a good estimate of the QOL can be determined by the degree of visual field loss in RP patients.

Refractory Uveitis in Patient with Castleman Disease Successfully Treated with Tocilizumab

Although multicentric Castleman disease is a rare but life-threatening disease, eye complications are extremely uncommon. We present a case of refractory uveitis accompanied with Castleman disease successfully treated with tocilizumab. A 58-year-old man with Castleman disease was introduced for refractory uveitis to Chiba University Hospital. Large cells were detected in the anterior chamber and increased vascular permeability of retinal vessels has been found in both eyes. Although the patient was treated with oral and eye drop steroid treatment, the uveitis symptoms had not decreased. The serum levels of CRP and IL-6 were increased. The level of IL-6 concentration in the anterior chamber was the same as the serum level of IL-6. The humanized anti-IL-6 receptor-antibody (tocilizumab) was administrated for the patient because of poor general condition. After tocilizumab treatment, large cells in the anterior chamber were undetectable and vascular permeability was improved in FA. The serum levels of CRP and IL-6 decreased and the general condition improved. The side effect of tocilizumab was not observed during the treatment. Tocilizumab treatment was significantly effective for uveitis accompanied with Castleman disease. Although it is extremely rare, uveitis accompanied with Castleman disease may be one of the hallmarks to consider tocilizumab treatment.

Comparison of photodynamic therapy to transpupillary thermotherapy for polypoidal choroidal vasculopathy

PurposeTo compare the therapeutic efficacy of photodynamic therapy (PDT) to that of transpupillary thermotherapy (TTT) for polypoidal choroidal vasculopathy (PCV).MethodsPDT or TTT was performed on 46 eyes of 46 patients with PCV; 19 eyes were treated with TTT (TTT group) and 27 eyes with PDT (PDT group). PCV was diagnosed by fundus examination, fluorescein angiography (FA) , and indocyanine green angiography (ICGA) . The best-corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution (logMAR) units and OCT-determined foveal thickness were evaluated before and after treatment. For statistical analyses, the Student’s t-test and χ2 test were used.ResultsThe number of treatments during the 12-month follow-up period was significantly higher in the TTT group (1.7 times) than in the PDT group (1.3 times; P=0.0134). The difference in the BCVA between the TTT and PDT groups at the baseline was not significant (P=0.3150), but the BCVA in the PDT group was significantly better than that in the TTT group at 3, 6, and 12 months after treatment (P=0.0093, P=0.0074, P=0.0006, respectively). The foveal thickness decreased markedly at 6 months after treatment in the PDT group (P<0.0001) but not significantly in the TTT group (P=0.8982). A vitreous haemorrhage was observed after treatment in two eyes in the TTT group.ConclusionsBCVA was significantly better and the fovea was significantly thinner in the PDT group than in the TTT group after treatment. Thus, PDT may be more effective than TTT for the treatment of eyes with PCV.

Diabetes Mellitus and Retinal Vein Occlusion as Risk Factors for Open Angle Glaucoma and Neuroprotective Therapies for Retinal Ganglion Cell Neuropathy

Glaucoma, diabetic retinopathy (DR), and retinal vein occlusion (RVO) are major diseases that can lead to blindness and affect mainly the elderly population worldwide. The results of recent investigations have demonstrated that the death of retinal ganglion cells (RGCs) and their axons is the common pathological change in these three disease processes. The exact mechanism that is responsible for the onset and progression of RGC death and axonal degeneration in patients with glaucoma, DR and RVO has not been definitively determined. Thus, identifying the risk factors for the onset and the progression of RGC neuropathy can help in deciding not only the specific treatments but also whether the treatments should be initiated, withheld, or augmented in individuals with glaucoma, DR, and RVO. This review describes the major risk factors for the onset of glaucoma, and the factors associated with the progression of glaucoma that have been obtained from large population-based prevalence and incidence studies. In addition, the potential risk factors for glaucoma, diabetes mellitus, and RVO are discussed in terms of the results obtained by both clinical and laboratory studies. This review introduces potential neuroprotective therapies for damaged RGC in eyes with RGC neuropathy, and the factors that should be considered for a complete therapy for the RGC neuropathy involved in glaucoma, DR and RVO. Neuroprotective therapies combined with a reduction of the IOP should be considered for the complete management of RGC neuropathy involved in glaucoma, DR and RVO.