Effectiveness of a photoscreener in identifying undiagnosed unilateral amblyopia at vision screening of 3-year-old children in Japan.

PURPOSE: In Japan a basic preparatory ophthalmic examination is routinely performed for 3-year-old children. This study aimed to determine the value of incorporating a photoscreener into the examination and evaluate parents' satisfaction with the photoscreener examination. STUDY DESIGN: Prospective study. METHODS: Children aged 42-47 months in Nagasaki City, Japan, underwent a visual acuity test by a parent at home and by automated vision screening using a photoscreener at their local municipal health center between October 2018 and March 2019. Subjects were children referred to Nagasaki University Hospital for examination after failing either test. Children previously diagnosed with strabismus and/or amblyopia were excluded. A questionnaire survey evaluated the level of satisfaction with the photoscreener-based screening by parents who attended these examinations at the local municipal health center. RESULTS: Of children who completed the two tests, 52 (failed visual acuity test, 3; failed photoscreener examination, 49) were referred for examination. Of the 49 photoscreener failures, 12 were diagnosed with amblyopia: unilateral amblyopia with anisometropic hyperopia in 10 (83.3%), and bilateral amblyopia with astigmatism and hyperopia in 2 (16.7%). The photoscreener detected all 12 cases of amblyopia, whereas the home-based visual acuity test detected only two cases. More than 80% of 1035 parents were satisfied with the photoscreener examination. CONCLUSION: Unilateral amblyopia with anisometropic hyperopia was easily overlooked with the home-based test but was detectable by photoscreener examination. The photoscreener proved to be an effective screening tool for amblyopia in children and was considered a satisfactory examination by a high proportion of parents.

Retinal Vascular Resistance Significantly Correlates With Visual Acuity After 1 Year of Anti-VEGF Therapy in Central Retinal Vein Occlusion.

Purpose: To investigate whether the resistivity of all retinal vessels, termed total capillary resistance (TCR), after anti-vascular endothelial growth factor (VEGF) treatment was correlated with the outcomes of patients with macular edema secondary to central retinal vein occlusion (CRVO). Methods: In total, 67 patients with nonischemic CRVO were enrolled in this retrospective observational case series. In each patient, we examined visual acuity; central retinal thickness (CRT); mean blur rate (MBR), which represents retinal blood flow velocity; and TCR. MBR and TCR were measured by laser speckle flowgraphy. Results: During the 1-year follow-up period, nine of 67 eyes (13.4%) converted to the ischemic type (converted group), whereas 58 eyes (86.6%) remained unchanged (nonischemic group). Mean CRT significantly decreased in all groups; however, the mean visual acuity significantly improved only in the nonischemic group. Mean MBR significantly increased in the nonischemic group but remained unchanged in the converted group. Mean TCR was significantly reduced in the nonischemic group but remained unchanged in the converted group. Multiple linear regression analysis revealed that MBR and TCR were the independent factors with the strongest and second strongest correlations with visual acuity after treatment, respectively. Conclusions: These findings suggest that measurements of the independent factors MBR and TCR are useful for evaluating anti-VEGF treatments in patients with CRVO. Translational Relevance: Development of clinically relevant technologies.

Retinal Microvascular Resistance Estimated from Waveform Analysis Is Significantly Higher With a Threshold Value in Central Retinal Vein Occlusion.

Purpose: Evaluation of blood flow is useful for understanding the severity of central retinal vein occlusion (CRVO). Actual blood flow may be determined by the resistivity of the retinal vein in CRVO. We have previously evaluated mean blur rate (MBR) to reflect total retinal blood flow velocity in CRVO cases using laser speckle flowgraphy (LSFG). This study evaluated retinal total vascular resistance in CRVO cases using the new index of total capillary resistance (TCR) from LSFG. Methods: We measured the TCR of 68 CRVO patients who visited Nagasaki University Hospital between 2009 and 2016 and 42 age-matched controls without systemic disease. We compared TCRs among control eyes, CRVO fellow eyes, and CRVO affected eyes. A CRVO threshold value was then obtained from the receiver operating characteristic curve. Results: MBR was significantly lower for CRVO affected eyes (20.3 ± 8.2) than for control eyes (37.5 ± 8.4; P < 0.01) and CRVO fellow eyes (36.4 ± 10.0; P < 0.01, Dunn's test). TCR was significantly higher for CRVO affected eyes (1.20 ± 0.55) than for control eyes (0.68 ± 0.2; P < 0.01) and CRVO fellow eyes (0.81 ± 0.28; P < 0.01, Dunn's test). The threshold for the presence of CRVO was 0.93 and area under the curve was 0.84. Conclusions: By measuring TCR in addition to MBR, more detailed information regarding CRVO pathology can be obtained. Translational Relevance: Comparison of values before and after treatment may be useful for evaluating the effects of treatment.

Quinone-based antibody labeling reagent for enzyme-free chemiluminescent immunoassays. Application to avidin and biotinylated anti-rabbit IgG labeling.

Chemiluminescence-enzyme immunoassays make it possible to measure trace components with high sensitivity and selectivity due to the high specificity of the antigen-antibody reaction and the high sensitivity of chemiluminescence assays. However, using an enzyme-labeled antibody suffers from many problems such as low reproducibility due to the instability of the enzyme and inhibition of antigen-antibody reaction due to its steric effect. Therefore, herein we report an innovative non-enzymatic chemiluminescence immunoassays labeling reagent through using quinone as a signal-generating tag coupled with biotin as a binder, to overcome enzymatic labeling problems. Biotinylated-1,4-naphthoquinone (biotin-NQ) was synthesized and characterized and it could produce long-lasting chemiluminescence upon mixing with dithiothreitol and luminol based on the redox cycle of quinone. Biotin-NQ showed exceptional stability towards different stress factors that may be encountered during performing the immunoassay such as high temperatures, highly acidic and alkaline conditions, and repeated freeze-thaw cycles. On the other hand, all these conditions lead to decreased labeling enzyme reactivity due to possible denaturation of its protein structure. Finally, the measurement of the biotin-labeled antibody was successfully performed using biotin-NQ and avidin. As a result, the antibody could be detected down to 25.7 nM which is 2.5 times sensitive than biotin-HRP chemiluminescence-enzyme immunoassays. Moreover, our method was applied successfully for determination of avidin using immobilized biotinylated antibody and biotin-NQ, which simulates immunoassays. Avidin could be detected down to 23.4 nM with excellent linearity (r = 0.996). Accordingly, our developed reagent, biotin-NQ, could be used as a universal highly stable, cost-effective, and steric free non-enzymatic label for immunoassays.

Three cases of acute sterile corneal melt after cataract surgery.

PURPOSE: To report three cases of acute sterile corneal melt after cataract surgery. OBSERVATIONS: Case 1 was a 21-year-old male presenting with a corneal perforation of his right eye at 10 days after cataract surgery. Case 2 was a 67-year-old male who developed a corneal melt in his left eye at 15 days after cataract surgery. Case 3 was a 70-year-old female with a corneal melt of her left eye at 7 days after cataract surgery. None of the cases exhibited any signs of infection. Topical nonsteroidal anti-inflammatory drug use, dry eye, systemic autoimmune diseases, and/or a combination of these were present in patients who developed corneal melt after cataract surgery. CONCLUSIONS AND IMPORTANCE: Corneal melt cases can occur early after cataract surgery, thereby leading to corneal thinning and perforation.

Differential activation of proapoptotic molecules between mouse and rat models of distal motor trigeminal denervation.

BACKGROUND: We previously developed a rat trigeminal motor neuron axotomy model involving masseter and temporal muscle resection to study pathological changes of the central nucleus after peripheral nerve injury caused by oral surgery. Because motor neurons are reported to be more vulnerable to axotomy in mice than rats, we compared the degeneration process of the trigeminal motor nucleus in the rat model with a similar mouse model. METHODS: We removed masseter and temporal muscles of adult mice or rats. Animals were sacrificed at 3, 7, 14, 28, 42, and 56 days post-operation, and the trigeminal motor nuclei were histologically analyzed. RESULTS: Size reduction, but no neuronal loss, was seen in the trigeminal motor nuclei in both mice and rats. Time-dependent Noxa expression, starting at 1 week post-operation (wpo), was seen in the mouse model. By 8 wpo, mice expressed a higher level of Noxa than rats. Additionally, we noted persistent expression of cleaved caspase-3 in mice but not in rats. Conversely, apoptosis-inducing factor (AIF), which executes DNA fragmentation in the nucleus, was not translocated to the nucleus in either model. CONCLUSIONS: Our findings indicate differential activation of motor neuron apoptosis pathways after axotomy in mice and rats. Lack of activation of caspase-independent pathways and distal end denervation in our model might be related to the survival of motor neurons after axonal injury. These findings could be relevant to future neuroprotective strategies for peripheral nerve injury caused by oral surgeries.

A simple and high-yield method for preparation of rat microglial cultures utilizing Aclar plastic film.

Microglia are implicated in both neuroprotection and neurodegeneration, and are a key area of interest with respect to various CNS diseases. Until now, primary microglia prepared by various isolation methods have been widely used to investigate their role in CNS diseases. However, there are some problems with the current isolation methods, such as the numbers of animals required in order to obtain sufficient numbers of microglial cells due to low yields, and also the long periods of culture required. We herein describe a simple, high-yield method for isolating not only primary microglia, but also immortalized microglial cells. Our method allows for the isolation of an almost pure population of microglia with only two steps. First, a primary mixed neural culture was prepared from the brains of 3-day-old postnatal rats. Next, primary microglia were collected for 2 h by adhesion to Aclar plastic film. The average yield by this method was approximately 50 times higher than that of the conventional shaking method. Immortalized microglial cells could also be prepared based on this procedure. A plasmid vector encoding the SV40 large T antigen was transfected into the mixed neural culture using a calcium phosphate precipitation method. Then, proliferating immortalized microglia were collected after several weeks in a similar fashion. Several clones were obtained by limited dilution and one of the immortalized cell lines was designated SMK. The SMK cells exhibited markers specific for the microglia lineage, including Iba-1, CD11b, CD45, CD68, major histocompatibility complex (MHC) class I and MHC class II, but not for the astrocyte-specific markers, GFAP and glutamate aspartate transporter. SMK also showed phagocytic activity. In conclusion, this method resulted in a high-yield preparation of microglial cultures with ease and reproducibility.