Finite Element Analysis of Changes in Deformation of Intraocular Segments by Airbag Impact in Eyes of Various Axial Lengths.

Background: We studied the kinetic phenomenon of an airbag impact on eyes with different axial lengths using finite element analysis (FEA) to sequentially determine the physical and mechanical responses of intraocular segments at various airbag deployment velocities. Methods: The human eye model we created was used in simulations with the FEA program PAM-GENERISTM. The airbag was set to impact eyes with axial lengths of 21.85 mm (hyperopia), 23.85 mm (emmetropia) and 25.85 mm (myopia), at initial velocities of 20, 30, 40, 50 and 60 m/s. The deformation rate was calculated as the ratio of the length of three segments, anterior chamber, lens and vitreous, to that at the baseline from 0.2 ms to 2.0 ms after the airbag impact. Results: Deformation rate of the anterior chamber was greater than that of other segments, especially in the early phase, 0.2-0.4 ms after the impact (P < 0.001), and it reached its peak, 80%, at 0.8 ms. A higher deformation rate in the anterior chamber was found in hyperopia compared with other axial length eyes in the first half period, 0.2-0.8 ms, followed by the rate in emmetropia (P < 0.001). The lens deformation rate was low, its peak ranging from 40% to 75%, and exceeded that of the anterior chamber at 1.4 ms and 1.6 ms after the impact (P < 0.01). The vitreous deformation rate was lower throughout the simulation period than that of the other segments and ranged from a negative value (elongation) in the later phase. Conclusion: Airbag impact on the eyeball causes evident deformation, especially in the anterior chamber. The results obtained in this study, such as the time lag of the peak deformation between the anterior chamber and lens, suggest a clue to the pathophysiological mechanism of airbag ocular injury.

Evaluation of anti-adenoviral effects of the polyvinyl alcohol iodine ophthalmic solution.

PURPOSE: To investigate the virucidal effects of a polyvinyl alcohol iodine, Saniode, against 16 types of human mastadenovirus (HAdV) causing ophthalmic, respiratory, gastrointestinal, urinary, and systemic infections. STUDY DESIGN: Laboratory investigation METHODS: Fifty microliters of Saniode were exposed to 10 µL each containing HAdV virus stock solution of 1 × 106 copies/µL of HAdV-1, -2, -3, -4, 5, -6, -7, -8, -11, -37, -53, -54, -56, -64, -81, and -85 for 10 s, 30 s, 1 min, and 3 min. After neutralization with 0.5% sodium thiosulfate, the mixture was diluted by ten-fold serial dilution and inoculated into 24 wells containing confluent A549 cell monolayers. Virucidal effects were calculated relative to the positive control on days 7-10 and observed until 30 days post-infection. RESULTS: Saniode satisfied the EN-14476 criterion for virucidal effects (>99.99%) for all HAdV types at all exposure times, including at 10 s on days 7 to 10 post-infection. All types of HAdVs that reacted for > 1 min achieved 99.99% reduction, including after 30 days. CONCLUSION: Saniode displayed virucidal effects against all tested HAdV types. Currently, with no specific medication available for HAdVs in ocular infection, this could be an option to prevent the spread of keratoconjunctivitis.

Classification of Subtypes of Vernal Keratoconjunctivitis by Cluster Analysis Based on Clinical Features.

Background: Vernal keratoconjunctivitis (VKC) is a refractory ocular allergic disorder that mainly affects boys. A few studies have attempted to develop a classification of subtypes of VKC. In this study, we investigated a computational approach called cluster analysis to separate VKC cases into groups based on clinically relevant characteristics. Methods: In total, 41 consecutive patients clinically diagnosed with VKC at the Department of Ophthalmology of Fukuoka University Hospital were included. Patients were treated with immunosuppressive eye drops without simultaneous corticosteroid eye drops, except for the occurrence of exacerbations. Collated variables were age at onset, clinical score of ocular lesions at baseline, clinical score of ocular lesions at final visit, clinical score of atopic dermatitis (AD) at baseline, frequency of exacerbations of VKC, serum total IgE level and peripheral blood eosinophil count. Results: VKC patients were grouped into three clusters by cluster analysis, and cluster 1, 2, and 3 comprised 25, 9 and 7 cases, respectively. There were differences in the incidence of complications of AD and age at onset among the clusters; therefore, we named the three clusters for better understanding as traditional VKC (cluster 1), early-onset atopic keratoconjunctivitis (AKC)/VKC (cluster 2) and puberty-onset AKC (cluster 3). Conclusion: We found in this study that VKC in childhood has three phenotypes which were previously unknown. Our findings may help to establish precision medicine by focusing on the phenotype of each case to develop individualized medicine to prevent exacerbations.

Finite Element Analysis of Changes in Tensile Strain by Airsoft Gun Impact on Eye and Deformation Rate in Eyes of Various Axial Lengths.

PURPOSE: We have carried out three-dimensional finite element analysis (FEA) to determine the physical and mechanical response in several ocular injuries. We applied this FEA model to evaluate an airsoft gun impact on an eye and the deformation rate of eyes of various axial lengths at various velocities. METHODS: This study was carried out on a human eye model using an FEA program created by Nihon, ESI Group. The airsoft gun pellet was set to impact the eye at initial velocities of 45, 60 and 75 m/s with the addition of variation in axial length of 20 mm (hyperopia), 22 mm (emmetropia), 24 mm (myopia) and 26 mm (high myopia). Deformation of the eye was calculated as the decrease rate of the volume of the eyeball and the decrease rate of the axial length. RESULTS: In all emmetropic cases, the cornea reached its strain threshold during the impact, and scleral strain showed a patchy strength distribution in the simulation. The deformation was most evident in the anterior segment, while deformation of the posterior segment was less. The decrease rate of the volume of the eyeball and decrease rate of the axial length were highest in the hyperopic eye, followed by the emmetropic eye and myopic eye, and the high myopic eye showed the lowest decrease rates among the four axial lengths in all impact velocity simulations. CONCLUSION: These results suggest that hyperopic eyes are most susceptible to deformation by an airsoft gun impact compared with other axial length eye models in this simulation. The considerable deformation by an airsoft gun impact shown in this study might indicate the necessity of ocular protection to avoid permanent eye injury. FEA using a human eyeball model might be a useful method to analyze and predict the mechanical features of ocular injury by an airsoft gun.

Characteristic of slow growth in cell culture of adenovirus type 54 causing nationwide outbreak epidemic keratoconjunctivitis in Japan.

PURPOSE: To characterize the virological features of adenovirus type 54 (Ad54) causing nationwide outbreak of severe epidemic keratoconjunctivitis (EKC) in Japan, we comparatively analysed the viral propagation phenotype of Ad54 and other Ads: type 37 (Ad37), 64 (Ad64), and 5 (Ad5), in A549 cells quantitatively. STUDY DESIGN: Laboratory investigation. METHODS: We compared the growth rate of Ads using copy numbers and cytopathic effect observation during propagation in A549 cell lines. Expressions of mRNA of E1 gene were also calculated and compared. Phylogenetic analysis of the region, including putative promoter of E1 gene and E1 open reading frame (ORF), were performed. RESULTS: Increases in viral loads, growth rate, and viral propagation were slower for Ad54 than for other Ads. The expression level of the E1 gene per infected cell was lower for Ad54 than for other Ad types on post-infection day 1. Phylogenetic analysis of the E1 gene putative promoter and ORF revealed Ad54 was the closest to Ad type 8. CONCLUSION: The propagation of Ad54 in A549 is slow compared with Ad37, Ad64 and Ad5. This slow propagation could have been caused by slow genomic replication resulting from delayed viral entry or E1 transcription initiation. The EKC caused by Ad54 needs more attention because the slow propagation of Ad54 may contribute to prolonged disease duration.

Clinical outcome after air-assisted manual deep anterior lamellar keratoplasty for fungal keratitis poorly responsive to medical treatment.

PURPOSE: Fungal keratitis remains an important disorder because of difficulty in its diagnosis, and some patients do not respond to medical treatment using antifungal local and systemic agents. This study was carried out to determine the therapeutic value of air-assisted manual therapeutic deep anterior lamellar keratoplasty (TDALK) in the treatment of fungal keratitis not curable by antifungal chemotherapy. METHODS: Seventeen patients (18 eyes) who were referred to Fukuoka University Hospital and treated surgically from January 2006 to April 2018, in whom a diagnosis of fungal keratitis was confirmed by typical clinical findings and microbiological or histological analysis of corneal specimens, and who were poorly responsive to topical and systemic antifungal medication, whereas the lesion had not resulted in corneal perforation, were enrolled in this study and were treated by air-assisted manual TDALK. Clinical outcomes including treatment course, therapeutic success rate, visual acuity outcomes and graft clarity rate were analyzed. RESULTS: The most common pathogen was Fusarium, followed by Candida and Aspergillus. Beneficial therapeutic results (a clear or translucent graft) were achieved in 15 of 18 eyes (83%). There was no recurrence of infection and resulting visual acuity ≤0.15 logarithm of minimal angle of resolution unit was achieved in 15 eyes (83%). Intraoperative microperforation of Descemet's membrane (DM) was not observed in any patients. CONCLUSION: Air-assisted manual TDALK can be effective for treating severe fungal keratitis. In addition, air-assisted manual TDALK might be an alternative procedure to big-bubble DALK, because it can provide ambulatory vision and can preserve potentiality of vision with less risk of intraoperative perforation of DM.

Evaluation of adenovirus amplified detection of immunochromatographic test using tears including conjunctival exudate in patients with adenoviral keratoconjunctivitis.

BACKGROUND: We evaluated a novel silver amplification immunochromatography test for rapid detection of adenovirus (AdV) antigen equipped with an automated reader system using tears including conjunctival exudate in patients with adenoviral keratoconjunctivitis. METHODS: Two kinds of immunochromatographic (IC) kits, a conventional IC kit for conjunctival scrapings (control kit) and an IC kit using tears including conjunctival exudate collected by pressing a filter paper strip on the conjunctiva (test kit), were tested on 90 patients who attended Migita Eye Clinic with suspected adenoviral conjunctivitis. The results of the test kits were automatically obtained by a specific reader, which was based on silver amplification immunochromatography system, in 15 min. The detection of AdV was confirmed by real-time polymerase chain reaction (PCR) method, and typing was performed by direct sequencing. Comparative dilution assay was carried out with the two kits, using AdV type 3 and type 54 strains. RESULTS: The sensitivity of the control kit and test kit was 89.8% and 98.3%, respectively. The specificity of both kits was 100%. A significant difference in the sensitivities of the two IC kits against PCR positivity was observed (P < 0.01). A significant correlation was found between AdV DNA copy numbers on a logarithmic scale obtained with the two tests (P < 0.01). The sensitivity of the test kit was 32-64-fold higher than that of the control kit without silver amplification for both AdV types. CONCLUSIONS: These results suggest that this novel amplified AdV detection kit using tears including conjunctival exudate is useful, because it decreases patients' discomfort from specimen collection and its sensitivity is significantly higher than that of the conventional IC kit.

Evaluation of a silver-amplified immunochromatography kit for adenoviral conjunctivitis.

OBJECTIVE: To compare and evaluate the sensitivity of a newly developed silver-amplified immunochromatography (SAI) kit with various immunochromatography (IC) kits for adenoviruses based on the detection limit (copies/test). METHODS: An SAI kit and four ophthalmic IC kits were evaluated. The detection limits of the five kits were determined using the limiting dilution method for 15 conjunctivitis-associated adenoviruses (adenoviruses 1, 2, 3, 4, 5, 7, 8, 11, 37, 53, 54, 56, 64, 81, and 85). The detection limits were presented as numerical values as determined by real-time polymerase chain reaction (PCR). RESULTS: The detection limit of the SAI kit for the adenovirus types ranged from 1.0 × 103 -5.0 × 10 4 copies/test (geometric mean, 4.7 × 10 3 ). SAI had a 10-250-fold lower detection limit than the four IC kits for all adenoviruses studied. There were also differences in detection limits among the adenovirus types for each kit. DISCUSSION: The detection limit of the SAI kit was drastically reduced because the silver-amplification reaction increased the color development sensitivity. The results revealed the high sensitivity of SAI for detecting adenoviruses and suggested its usefulness for conjunctivitis examination.

Clinical and virological analysis of epidemic keratoconjunctivitis caused by adenovirus type 54 in a regional ophthalmic clinic in Kyushu, Japan.

BACKGROUND: Human adenovirus type 54 (HAdV-54) is a novel type of adenovirus that belongs to species D and has thus far been detected only in Japan in patients with epidemic keratoconjunctivitis (EKC). There was a large nationwide outbreak of HAdV-54 EKC from 2015 to 2016 in Japan. The clinical characteristics of an outbreak of HAdV-54 conjunctivitis treated in a regional ophthalmic clinic in Fukuoka, Japan, in 2016 were analyzed. PATIENTS AND METHODS: A consecutive series of 55 cases diagnosed clinically as EKC confirmed by HAdV-54 detection from conjunctival scrapings by polymerase chain reaction (PCR) method between 17 June 2016 and 29 August 2016 were enrolled. Viral DNA copies were counted by real-time PCR method. The clinical findings were recorded at the first visit to the clinic and evaluated. RESULTS: In the analysis of the relationship between mean clinical score groups and several factors, such as days after onset, sex, HAdV DNA number on a logarithmic scale, and age, most factors did not show a significant difference in clinical score between groups. However, mean clinical score of cases aged <23 years was significantly higher than that of cases aged ≥23 years (P<0.01). The correlation coefficient between DNA copies on a logarithmic scale and clinical score was 0.280, and a significant correlation was observed (P<0.05). Multiple subepithelial corneal infiltrates (MSI) were observed in 24 out of 31 cases (77%). CONCLUSION: These results suggested that the clinical features in the early phase of HAdV-54 keratoconjunctivitis were milder but the rate of MSI observed in the late phase was higher than those in previous epidemics of several HAdV types. The significant difference in clinical severity between age groups might be a virological characteristic of HAdV-54.