Chota Matsumoto

Methicillin-resistant Staphylococcus aureus and methicillin-resistant coagulase-negative Staphylococcus ocular surface infection efficacy of chloramphenicol eye drops.

Purpose Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus (MR-CNS) are two major multidrug-resistant pathogens. In this paper we report the prevalence of MRSA and MR-CNS in ocular surface infections. Methods We investigated the proportion of MRSA and MR-CNS in bacterial isolates from conjunctiva of elderly patients with and without bacterial conjunctivitis. The relationship between conjunctival MRSA carriers and general background conditions was studied. We evaluated the efficacy of chloramphenicol eye drops in the treatment of MRSA conjunctivitis. We also investigated the presence of MRSA and MR-CNS in lid skin and conjunctiva of patients with atopic dermatitis. Results In conjunctival bacterial flora of elderly patients the proportion of MRSA in S. aureus was 57%, and the proportion of MR-CNS in coagulase-negative Staphylococcus was 25%. Conjunctival MRSA carriers were more likely to have anemia, malignant tumor, liver dysfunction, and dementia, and to be postoperation and chronically bedridden. The efficacy rate of chloramphenicol eye drops in the treatment of MRSA conjunctivitis was 81%. In conjunctival sacs of patients with atopic dermatitis, S. aureus was the most frequent species (48%), and the proportion of MRSA was 18%. Conclusion Methicillin-resistant S. aureus and MR-CNS are widespread in elderly hospitalized patients and in patients with atopic dermatitis. Chloramphenicol eye drops were useful for the treatment of MRSA ocular surface infections.

Correlations between M-CHARTS and PHP Findings and Subjective Perception of Metamorphopsia in Patients with Macular Diseases

PURPOSE To assess the correlations between a patients subjective perception of metamorphopsia and the clinical measurements of metamorphopsia by M-CHARTS and PreView PHP (PHP). METHODS The authors designed a 10-item questionnaire focusing on the symptoms of metamorphopsia and verified its validity with a Rasch analysis. M-CHARTS measured the minimum visual angle of a dotted line needed to detect metamorphopsia, and PHP used the hyperacuity function for detection. Subjects were 39 patients with idiopathic epiretinal membrane (ERM), 22 patients with idiopathic macular hole (M-hole), 19 patients with age-related macular degeneration (AMD), and 51 healthy controls. RESULTS Rasch analysis suggested the elimination of one question. The nine-item questionnaire score significantly correlated to the M-CHARTS score in ERM (r = 0.59; P = 0.0004) but not in M-hole and to the PHP result in AMD (r = -0.29; P = 0.04) but not in ERM. Eighty percent of ERM patients with greater horizontal M-CHARTS score subjectively perceived horizontal metamorphopsia more often. M-CHARTS showed better sensitivities than PHP in both ERM (89% vs. 42%) and AMD (74% vs. 68%) and better specificity (100% vs. 71%) in healthy controls. Rasch analysis indicated that the present form of the questionnaire is better suited for moderate to severe cases of metamorphopsia than for mild cases. CONCLUSIONS The questionnaire appears to be a valid assessment of patient subjective perception of metamorphopsia and can be used to supplement the clinical measurements of metamorphopsia by M-CHARTS and PHP in patients with macular diseases.

Risk factors for progression of normal‐tension glaucoma under β‐blocker monotherapy

Purpose:  To prospectively study prognostic factors for normal‐tension glaucoma (NTG) under treatment with topical β‐blocker.

Detectability of glaucomatous changes using SAP, FDT, flicker perimetry, and OCT.

PurposeTo compare the detectability between glaucomatous visual field changes using standard automated perimetry (SAP), frequency doubling technology (FDT), short-wavelength automated perimetry (SWAP), and flicker perimetry and structural changes using optical coherence tomography (OCT). ParticipantsFifty-nine eyes of fifty-nine patients with open-angle glaucoma, 24 eyes of 24 glaucoma suspects (GSs), and 40 eyes of 40 healthy age-matched subjects. MethodsAll subjects underwent Humphrey visual field analyzer II 24-2 full threshold (SAP), Swedish interactive threshold algorithm-SWAP, FDT (30-1, 30-5, 24-2-1, 24-2-5), flicker perimetry on Octopus 311 (4-zone probability 38S), and Stratus OCT [fast retinal nerve fiber layer thickness (NFLT) and fast optic disc]. To evaluate the visual field, FDT and flicker used the number of abnormal points, whereas SAP used mean deviation (MD) and SWAP used both the number of abnormal points and MD. The areas under the receiver operating characteristic curves [area under the curve (AUCs)] and sensitivities at fixed specificities were used to assess the detectability of glaucoma. ResultsThe AUC for FDT 30-1, 30-5, 24-2-1, 24-2-5, flicker perimetry, SWAP (MD), and SWAP (number of abnormal points) were 0.95, 0.94, 0.88, 0.89, 0.99, 0.88, and 0.88 in the early glaucoma group and 0.67, 0.69, 0.65, 0.70, 0.80, 0.64, and 0.66 in the GS group, respectively. In the early glaucoma and GS groups, all OCT parameters had an AUC >0.81 except the disc area parameter. Especially, average NFLT had the highest AUC of 0.94 in the OCT parameters. ConclusionsFDT, SWAP, flicker perimetry, and OCT are all useful methods for discriminating between healthy eyes and eyes with early glaucoma. Among all 10 OCT parameters, NFLT has the highest sensitivity for detecting early glaucomatous changes in GS patients.

Structure-Function Mapping: Variability and Conviction in Tracing Retinal Nerve Fiber Bundles and Comparison to a Computational Model

PURPOSE We evaluated variability and conviction in tracing paths of retinal nerve fiber bundles (RNFBs) in retinal images, and compared traced paths to a computational model that produces anatomically-customized structure-function maps. METHODS Ten retinal images were overlaid with 24-2 visual field locations. Eight clinicians and 6 naïve observers traced RNFBs from each location to the optic nerve head (ONH), recording their best estimate and certain range of insertion. Three clinicians and 2 naïve observers traced RNFBs in 3 images, 3 times, 7 to 19 days apart. The model predicted 10° ONH sectors relating to each location. Variability and repeatability in best estimates, certain range width, and differences between best estimates and model-predictions were evaluated. RESULTS Median between-observer variability in best estimates was 27° (interquartile range [IQR] 20°-38°) for clinicians and 33° (IQR 22°-50°) for naïve observers. Median certain range width was 30° (IQR 14°-45°) for clinicians and 75° (IQR 45°-180°) for naïve observers. Median repeatability was 10° (IQR 5°-20°) for clinicians and 15° (IQR 10°-29°) for naïve observers. All measures were worse further from the ONH. Systematic differences between model predictions and best estimates were negligible; median absolute differences were 17° (IQR 9°-30°) for clinicians and 20° (IQR 10°-36°) for naïve observers. Larger departures from the model coincided with greater variability in tracing. CONCLUSIONS Concordance between the model and RNFB tracing was good, and greatest where tracing variability was lowest. When RNFB tracing is used for structure-function mapping, variability should be considered.

TGF-β2 promotes RPE cell invasion into a collagen gel by mediating urokinase-type plasminogen activator (uPA) expression.

Transforming growth factor-beta (TGF-β) is one of the main epithelial-mesenchymal transition (EMT)-inducing factors. In general, TGF-β-induced EMT promotes cell migration and invasion. TGF-β also acts as a potent regulator of pericellular proteolysis by regulating the expression and secretion of plasminogen activators. Urokinase-type plasminogen activator (uPA) is a serine protease that binds to its cell surface receptor (uPAR) with high affinity. uPA binding to uPAR stimulates uPARs interaction with transmembrane proteins, such as integrins, to regulate cytoskeletal reorganization and cell migration, differentiation and proliferation. However, the influence of TGF-β and the uPA/uPAR system on EMT in retinal pigment epithelial (RPE) cells is still unclear. The purpose of this study was to determine the effect of TGF-β2, which is the predominant isoform in the retina, and the uPA/uPAR system on RPE cells. In this study, we first examined the effect of TGF-β2 and/or the inhibitor of uPA (u-PA-STOP(®)) on the proliferation of a human retinal pigment epithelial cell line (ARPE-19 cells). Treatment with TGF-β2 or u-PA-STOP(®) suppressed cell proliferation. Combination treatment of TGF-β2 and u-PA-STOP(®) enhanced cell growth suppression. Furthermore, western blot analysis, fibrin zymography and real-time reverse transcription PCR showed that that TGF-β2 induced EMT in ARPE-19 cells and that the expression of uPA and uPAR expression was up-regulated during EMT. The TGF-β inhibitor SB431542 suppressed TGF-β2-stimulated uPA expression and secretion but did not suppress uPAR expression. Furthermore, we seeded ARPE-19 cells onto Transwell chambers and allowed them to invade the collagen matrix in the presence of TGF-β2 alone or with TGF-β2 and u-PA-STOP(®). TGF-β2 treatment induced ARPE-19 cell invasion into the collagen gel. Treatment with a combination of TGF-β2 and the uPA inhibitor strongly inhibited ARPE-19 cell invasion compared with treatment with TGF-β2 alone. Furthermore, the interaction between uPA and ARPE-19 cells was analyzed using a surface plasmon biosensor system. The binding of uPA to ARPE-19 cells was observed. In addition, TGF-β2 significantly promoted the binding activity of uPA to ARPE-19 cells in a time-dependent or cell-number-dependent fashion. These results indicate that TGF-β-induced EMT-associated phenotype changes in ARPE-19 cells and the invasiveness of ARPE-19 cells into a collagen gel matrix are mediated, at least in part, by uPA.

Quantification of changes in metamorphopsia and retinal contraction in eyes with spontaneous separation of idiopathic epiretinal membrane.

BackgroundTo quantify changes in metamorphopsia and retinal contraction in eyes with idiopathic epiretinal membrane (ERM) before and after a spontaneous separation of ERM.MethodsAmong 92 eyes of 92 patients with idiopathic ERM who were followed up at our hospital, 5 eyes of 5 patients had experienced a spontaneous separation of ERM during the follow-up period. Patient’s metamorphopsia was assessed horizontally and vertically by a metamorphopsia chart developed by our group, M-CHARTS, to obtain the horizontal (MH) and vertical (MV) metamorphopsia scores. Difference in the scores before and after the membrane separation represents change in patient’s metamorphopsia. Changes in retinal contraction were also evaluated horizontally and vertically with our original software for fundus image analysis. The difference between M-CHARTS scores and distances of retinal vessel movements with before and after membrane separation were measured.ResultsAll five subjects showed a decrease in the retinal contraction. Improved visual acuity was observed in three subjects, and no change was seen in the other two. Four subjects obtained better metamorphopsia scores after the membrane separation, while the other one was not detected with metamorphopsia by M-CHARTS either before or after the separation. In subjects with an improved MV, horizontal retinal movement was seen larger than the vertical movement. Similarly, the subjects with an improved MH indicated a larger vertical retinal movement than the horizontal movement.ConclusionsThe direction of patient’s metamorphopsia closely associated with the direction of retinal contraction before and after a spontaneous separation of ERM.

Herpes Simplex Virus-2 Quantification by Real-time Polymerase Chain Reaction in Acute Retinal Necrosis

after treatment even though a high dose of ACV was administered. Second, 4 weeks after treatment, VZV-DNA was negative in PCR even though cells and flare could be observed in the anterior chamber of the diseased eye. PCR has been performed successfully to detect viral DNA in ocular samples. Nagae et al. reported that in 12 eyes of 9 patients with viral retinitis, causative viral DNA was detected by PCR either from the tear fluid (1/12, 8%), the aqueous (6/7, 86%), or the vitreous (1/1, 100%). However, is PCR the most dependable procedure during treatment? Mochizuki suggested that viral DNA detected by PCR in the anterior chamber might turn negative naturally about 60 days after onset of the disease, either as an effect of ACV therapy or as a result of the autoimmune disease. However, the case reported here is only one example; more reports and further information are necessary to reach a conclusion.

Multicenter evaluation of tendency-oriented perimetry (TOP) using the G1 grid.

Purpose The G1-TOP program is a short automated perimetric strategy which sub-divides the G1 grid of 59 points into four sub-grids. Each point is tested only once, but each patients response is used to modify that particular point and the surrounding ones from the remaining sub-grids. This study compared the results of the G1-TOP program with the Standard Bracketing strategy. Methods Eleven participating institutions provided data from 213 patients (406 eyes). The main group consisted of 284 glaucomas and 55 glaucoma suspects. Other groups included 31 eyes with neurological disorders, 20 with chorioretinal lesions and 16 normal eyes. Mean age was 62.7 ± 15.4 (range 14–88) years. All subjects had previous perimetric experience and visual acuity better than 0.5. Examination included G1-Standard Bracketing and G1-TOP testing, in interchangeable order, with the Octopus 1-2-3 perimeter. Results The correlation coefficient for mean defect (MD) was 0.95. Standard error (YX) for MD, square root of loss variance (LV) and individual thresholds were 1.86 dB, 1.29 dB, and 4.72 dB, respectively. Mean sensitivity values were similar (difference 0.04 ± 1.87 dB) (p>0.05). Mean duration for G1-TOP was 2.19 ± 0.26 min, while G1-Standard Bracketing took 11.51 ± 1.52 min (ratio 1/5.1, or a net reduction of 80.4%). The sensitivity of G1-TOP versus G1-Standard Bracketing was: glaucoma 77.1/78.5, glaucoma suspects 38.2/47.3, neurological disorders 87.1/87.1 and chorioretinal lesions 80.0/85.0. Conclusions The G1-TOP program gave very similar results to G1-Standard Bracketing in only 20% of the time required by the standard strategy.

Influence of target size and eccentricity on binocular summation of reaction time in kinetic perimetry

To assess how target size and eccentricity affect binocular summation (BS) of reaction time (RT) at suprathreshold level, we measured RT using targets of 0.108° and 0.216° at four eccentricities (0°, 5°, 15°, 25°) in six normal volunteers. The difference between the monocular/binocular RT differentials for both sizes significantly increased in the periphery (P<0.05). The smaller target required significantly longer monocular RT at 25° (P<0.01) and generated greater neural summation than the larger target (P<0.01). This suggests that when monocular function has reached its limit in visual processing in the periphery, BS increases, facilitates visual processing, and shortens binocular RT.