Blocking Air in the Filtering Bleb: Effects on Graft Adhesion After Descemet's Stripping Automated Endothelial Keratoplasty.

BACKGROUND: To evaluate the outcome of Descemet's stripping automated endothelial keratoplasty (DSAEK) with "blocking air" in the filtering bleb in patients with previous trabeculectomy. METHODS: In total, 299 eyes in 283 patients who underwent DSAEK were retrospectively reviewed. Endothelial graft adhesion, intraocular pressure (IOP), and air volume in the anterior chamber with (group A) or without (group B) a filtering bleb were compared between the groups. Group A was divided into two subgroups according to the presence (group A1) or absence (group A2) of air in the filtering bleb; the same three factors were compared between the subgroups. RESULTS: The graft detachment rate was significantly higher in group A (14.3%) than in group B (6.5%) (p = 0.04). IOP was significantly lower in group A than in group B before surgery (p = 0.01), at the end of surgery (p = 0.04), at three hours (p < 0.001), and one week postoperatively (p = 0.02). The graft detachment rate did not significantly differ between groups A1 and A2. There were no differences in IOP at each follow-up time, whereas there was a statistically significant increase in IOP from the preoperative measurement to the end of surgery in group A1 (21.0±7.0 mmHg) compared with group A2 (14.2±8.6 mmHg) (p = 0.02). CONCLUSIONS: The presence of blocking air in the filtering bleb helps ensure increased IOP during the early postoperative period but had no significant effect on graft detachment rates.

Rapid Corneal Calcification Following Endothelial Keratoplasty: A Case Report.

Corneal calcification typically progresses slowly but can occasionally advance rapidly. This report details severe stromal calcification following repeat Descemet's stripping automated endothelial keratoplasty (DSAEK) in a 75-year-old patient with diabetes, hypertension, and prior ocular surgeries, including cataract surgery, intraocular lens extraction with suturing, and trabeculectomy. Persistent epithelial defects after the surgery led to rapid central stromal calcification within four weeks, significantly reducing visual acuity. Management included switching from betamethasone sodium phosphate to fluorometholone, facilitating complete epithelial recovery within two months. However, persistent stromal opacity necessitated a subsequent penetrating keratoplasty. Infrared absorption spectrophotometry identified calcium phosphate as the primary component of the calcification. This case highlights the importance of vigilant monitoring and proactive management of epithelial defects to prevent rapid calcification following endothelial keratoplasty.

Effectiveness of laser pulsed irradiation for antimicrobial photodynamic therapy.

The aim of this study was to compare two types of light irradiation devices for antimicrobial photodynamic therapy (aPDT). A 660-nm light-emitting diode (LED) and a 665-nm laser diode (LD) were used for light irradiation, and 0.1 mg/L TONS 504, a cationic chlorin derivative, was used as the photosensitizer. We evaluated the light attenuation along the vertical and horizontal directions, temperature rise following light irradiation, and aPDT efficacy against Staphylococcus aureus under different conditions: TONS 504 only, light irradiation only, and TONS 504 with either LED (30 J/cm2) or LD light irradiation (continuous: 30 J/cm2; pulsed: 20 J/cm2 at 2/3 duty cycle, 10 J/cm2 at 1/3 duty cycle). Both LED and LD light intensities were inversely proportional to the square of the vertical distance from the irradiated area. Along the horizontal distance from the nadir of the light source, the LED light intensity attenuated according to the cosine quadrature law, while the LD light intensity did not attenuate within the measurable range. Following light irradiation, the temperature rise increased as the TONS 504 concentration increased in the order of pulsed LD < continuous LD < LED irradiation. aPDT with light irradiation only or TONS 504 only had no antimicrobial effect, while aPDT with TONS 504 under continuous or pulsed LD light irradiation provided approximately 3 log reduction at 30 J/cm2 and 20 J/cm2 and approximately 2 log reduction at 10 J/cm2. TONS 504-aPDT under pulsed LD light irradiation provided anti-microbial effect without significant temperature rise.

Refractory Fungal Keratitis Caused by Acrophialophora fusispora: A Case Report and Literature Review.

Acrophialophora fusispora is a filamentous fungus that is found in soil and rarely infects humans. We herein report the first case of fungal keratitis caused by A. fusispora in Japan and present a review of the literature on human infections with Acrophialophora species. A 62-year-old Japanese male on immunosuppressive therapy developed fungal keratitis after the removal of a corneal foreign body from his left eye. Voriconazole eye drops and systemic therapy for post-traumatic fungal keratitis did not resolve the infection, and the patient required a therapeutic corneal transplant. The isolate was identified as A. fusispora based on the nucleotide sequence of the internal transcribed spacer region. In a drug susceptibility test, the minimum inhibitory concentration of voriconazole was 0.5 µg/mL. Based on this case and previous cases from the literature review, fungal keratitis caused by A. fusispora is often refractory.

Efficacy of azithromycin hydrate ophthalmic solution for treatment of internal hordeolum and meibomitis with or without phlyctenular keratitis.

PURPOSE: To evaluate the efficacy of azithromycin hydrate ophthalmic solution for the treatment of internal hordeolum and meibomitis with or without phlyctenular keratitis. STUDY DESIGN: Retrospective study. METHODS: Patients diagnosed with internal hordeolum or meibomitis were prescribed azithromycin hydrate ophthalmic solution twice daily for 2 days and then once daily for 12 days. Depending on the presence of meibomitis-related keratoconjunctivitis (MRKC), we further divided the patients with meibomitis into three subgroups: meibomitis alone (non-MRKC group), meibomitis with non-phlyctenular MRKC (non-phlyctenular group), and meibomitis with phlyctenular MRKC (phlyctenular group). Inflammatory findings (eyelid redness and conjunctival hyperemia) were scored before and after treatment. Some patients also underwent culture testing fluids discharged by the meibomian gland orifices. RESULTS: Three patients (3 eyes) had internal hordeolum and 16 patients (16 eyes) had meibomitis. After treatment, the inflammatory findings disappeared in all eyes with internal hordeolum. Among the patients with meibomitis, three eyes were in the non-MRKC, six in the non-phlyctenular, and seven in the phlyctenular group. The inflammatory findings were significantly improved only in the phlyctenular group. Among seven eyes with positive culture results, Cutibacterium acnes was detected in five, and treatment improved the inflammatory findings in all of these eyes. CONCLUSION: Azithromycin hydrate ophthalmic solution is effective for the treatment of inflammatory meibomian gland diseases, including internal hordeolum and meibomitis. In particular, the agent is highly efficient in patients with phlyctenular MRKC.

Usefulness of smear microscopy for therapeutic decision-making in patients with infectious keratitis.

PURPOSE: To determine the usefulness of smears in the diagnosis of infectious keratitis by comparing smears and 2 different culture methods. STUDY DESIGN: Retrospective, observational study. METHODS: The foci of 73 patients diagnosed with infectious keratitis at Hiroshima University Hospital between July 2011 and September 2015 were abraded, and smear microscopy and culturing were performed. The microorganism detection rates and other parameters were compared. RESULTS: Microorganisms were detected in 47 of 73 specimens. Microorganisms were identified in 32 of 69 cases cultured on plain medium (detection rate, 46.4%) compared with 22 of 61 cases cultured on swab transport medium (detection rate, 36.1%). There was no significant difference in the microbial detection rate between the plain medium method and the swab transport medium method (P = 0.23). Smear microscopy and culture findings were concordant in 21 (28.8%) cases, and different microorganisms were detected in 9 cases. In 17 cases, the culture was negative, despite the presence of microorganisms on smear microscopy, and in 7 cases, the culture was positive, despite the absence of microorganisms on smear microscopy. The positivity rate of microbial detection was significantly higher when no antimicrobial agents had been administered previously (odds ratio 7.50, P = 0.017). CONCLUSION: Smear microscopy of abrasions from lesions is useful for the initiation of treatment for infectious keratitis. However, culture studies should be conducted at the same time to confirm antimicrobial sensitivity. If possible, smear microscopy should be performed before the initiation of antimicrobial therapy.

Case report: Medical treatment for limbal epithelial stem cell deficiency in patients treated for glaucoma.

Limbal epithelial stem cell deficiency (LSCD) is an abnormal corneal epithelial lesion with several causes. The patient was diagnosed using fluorescein staining. Bullous keratopathy, multiple surgeries, and drug-related damage can cause LSCD in glaucoma patients. We evaluated the medical treatment course for LSCD in patients with glaucoma. We retrospectively reviewed the electronic medical records of patients diagnosed with LSCD and investigated their background, course of treatment, and classification stages of LSCD before and after treatment. The global consensus classification system (stages IA-C, IIA-B, and III) proposed by Deng et al. (Cornea 2020) was used. Seven patients (two males) and eight eyes were studied. The median age of the patients was 82 years, and the mean duration of glaucoma treatment was 8 years. The patients had open-angle glaucoma (four eyes), exfoliation glaucoma (one eye), neovascular glaucoma (one eye), normal tension glaucoma (one eye), and uveitic glaucoma (one eye). Stage classifications at diagnosis were stage IA in four eyes and stages IC, IIA, IIB, and III in one eye each. All treatments were carried out with dry eye drops, steroid eye drops, and antibiotics. The mean duration of treatment was 1.4 years. The classifications at the time of the final visit were normal corneal epithelium (three eyes), stage IA (two eyes), IIA (one eye), and III (two eyes). Three eyes (37%) improved by more than one stage and one eye deteriorated by more than one stage. LSCD is long-lasting and difficult to treat in a short period; thus, it requires careful medical attention.

Case Report: Corneal Inlay Removal after Myofibroblast Detection under in Vivo Confocal Microscopy.

SIGNIFICANCE: Corneal inlays, one of the treatment options for presbyopia, are effective and safe, and various such devices have been developed. However, there have been cases of inlay removal due to complications or patient dissatisfaction. PURPOSE: The purpose of this study was to report a case of inlay removal due to corneal opacity after inlay implantation and the results of 5 years of follow-up. CASE REPORT: A 63-year-old man was referred to our hospital with visual disturbance and double vision in his left eye. Two years before presentation at our hospital, he had undergone bilateral laser in situ keratomileusis with corneal inlay implantation in the left eye at another clinic. Slit-lamp examinations showed paracentral corneal opacity. The patient was treated with tranilast eye drops for 18 months, with no progression of symptoms. However, 6 months after stopping the eye drop treatment, the opacity recurred, and vision acuity decreased, along with the formation of myofibroblasts around the inlay, as revealed by in vivo confocal microscopy. Consequently, the inlay was removed at the previous clinic. During the subsequent 5-year follow-up period, ophthalmic examination revealed reduced corneal opacity, although visual acuity did not change; moreover, no myofibroblast was found. CONCLUSIONS: Corneal inlays can sometimes cause complications. In this case, the patient experienced corneal fibrosis and associated vision loss. In vivo confocal microscopy detected myofibroblasts that cause corneal stromal fibrosis; thus, the removal was decided to avoid fibrosis progression.

Inflammatory Cells and Lipid Deposits Detected by in Vivo Confocal Microscopy in Brimonidine Tartrate Ophthalmic Solution-Related Corneal Disorders: A Case Series.

We reviewed the medical charts of five patients diagnosed with brimonidine tartrate (BT)-related corneal disorders. A fan-shaped corneal opacity was present in four patients and limbal corneal infiltrations were present in one patient. In vivo confocal microscopy revealed dendritic cells and lipid deposits in the fan-shaped opacity as well as neutrophils in limbal infiltrations. BT instillation was discontinued and topical administration of a corticosteroid was initiated for all patients. The limbal infiltrations improved after BT discontinuation. Conversely, the fan-shaped opacity remained in all affected patients. After a fan-shaped opacity has developed in a patient with a BT-related corneal disorder, the lesion is difficult to resolve. However, limbal infiltrations respond well to treatment. Therefore, BT should be discontinued and anti-inflammatory treatment initiated before a fan-shaped opacity forms.

Corneal Copper Deposition Secondary to Monoclonal Gammopathy in a Patient With Chronic Lymphocytic Leukemia: A Case Report.

Hypercupremia-induced corneal copper deposition secondary to monoclonal gammopathy is rare and shows a characteristic corneal opacity quite different from other causes of hypercupremia, such as Wilson's disease. This report describes a case of corneal copper deposition in a patient with monoclonal gammopathy associated with chronic lymphocytic leukemia. An 84-year-old man with slowly progressive corneal opacity was referred to our hospital. The corneal opacity was present at least five years ago. The patient's best-corrected visual acuity was 20/25 OU (in both eyes) at the initial visit to our hospital. Slit-lamp examination and anterior segment optical coherence tomography revealed bilateral brown-colored opacity localized to deep layers of the central cornea. In vivo confocal microscopy (IVCM) showed indistinct corneal stromal cells in the deep layer and endothelial cells. The possible differential diagnoses were corneal dystrophy and Wilson's disease, but the color, shape, or site of corneal opacity was inconsistent with the disease. As the patient had a history of chronic lymphocytic leukemia, which is often associated with monoclonal gammopathy, we suspected that the corneal opacity was copper deposition in association with the hematologic diseases. Laboratory examinations showed elevated serum copper and normal ceruloplasmin. Serum protein electrophoresis revealed significantly high IgG levels with depression of IgA, IgE, and IgM. These results supported our diagnosis. Followingly, we consulted the patient's attending hematologist, and the doctor initiated treatment for hypercupremia. In conclusion, hypercupremia secondary to monoclonal gammopathy should be considered a possible cause of central brown-colored corneal opacity.

Technical Report: Automatic Measurement of Corneal Nerve Fiber Area Using Versatile Software.

SIGNIFICANCE: In vivo confocal microscopy has become a popular method to observe the details of corneal structures. We consider the area of corneal structures to be a versatile index and have measured the areas of various corneal structures using a commercially available software. PURPOSE: This study aimed to evaluate the accuracy of software used to measure the corneal nerve fiber area. METHODS: The corneal structures of 11 healthy volunteers were visualized using in vivo confocal microscopy. The image that most clearly depicted the corneal nerve fibers of each participant was selected for analysis. The corneal nerve fiber area was automatically measured by the software. An experienced ophthalmologist then manually measured the corneal nerve fiber area in each image assessed by the software. The Pearson correlation test was used to determine the correlation coefficient between the corneal nerve fiber areas measured automatically and those measured manually. The correlation between the corneal nerve fiber area and the participant's age was also evaluated. RESULTS: A strong correlation was found between the corneal nerve fiber area measured automatically and the corneal nerve fiber area measured manually ( r = 0.98, P = 2.4 × 10 -7 ). The corneal nerve fiber area was not correlated with participant age, regardless of whether the area was measured automatically ( r = -0.26, P = .44) or manually ( r = -0.13, P = .71). CONCLUSIONS: The software used in this study automatically measures the corneal nerve fiber area with accuracy similar to that of manual measurement by an experienced ophthalmologist. This software has potential for use in quantifying the areas of various corneal structures.

Synergistic effect of TONS504-mediated photodynamic antimicrobial chemotherapy and additives widely contained in ophthalmic solutions: benzalkonium chloride and ethylenediaminetetraacetic acid.

TONS504 (C51H58N8O5I2), a chlorine derivative, effectively generates singlet oxygen by light activation and exhibits photodynamic antimicrobial effects (PAEs) on various pathogens. However, this photosensitizer has some limitations: a high tendency to self-aggregate and a relatively weak PAE for Gram-negative bacteria compared with Gram-positive bacteria. To overcome these limitations, the present study investigated the synergistic effects of the PAE of TONS504 and two additives commonly contained in ophthalmic solutions: benzalkonium chloride (BAC) or ethylenediaminetetraacetic acid (EDTA). Staphylococcus aureus and Pseudomonas aeruginosa were exposed to TONS504 and/or each additive. Photodynamic antimicrobial chemotherapy was performed with light irradiation centered at a wavelength of 665 nm with a total light energy of 30 J/cm2. Following incubation, the number of colonies formed was counted. Additionally, we examined the inhibitory effects of the additives on TONS504 self-aggregation by observing its absorption spectrum. Consequently, the PAEs of TONS504 on S. aureus were enhanced by both additives, and BAC displayed stronger synergistic effects on the bacteria than EDTA. By contrast, only EDTA increased the PAE on P. aeruginosa. The peak of the TONS504 absorption spectrum shifted to a longer wave length and the absorbance increased in the presence of BAC, suggesting that BAC inhibited the self-aggregation of the photosensitizer. In conclusion, the combination of BAC or EDTA and TONS504-mediated photodynamic antimicrobial chemotherapy exhibits a synergistic antimicrobial effect on S. aureus and P. aeruginosa. The optimal additive to enhance the PAE may differ between bacterial strains.

Vernal keratoconjunctivitis with a limbal mass lesion developing independently of severe papillae formation at the tarsal conjunctiva: a case report.

BACKGROUND: A hypertrophic limbal mass lesion is an uncommon finding of vernal keratoconjunctivitis; it normally occurs in eyes with severe papillae formation in the tarsal conjunctiva. We present a case with a limbal mass lesion in a patient with relatively mild allergic findings in the tarsal conjunctiva. CASE PRESENTATION: A 12-year-old Japanese boy displaying allergic conjunctivitis presented with a mass lesion at the inferior limbus in the left eye. Relatively mild papillae formation was found on the tarsal conjunctiva in both eyes. We diagnosed that the mass lesion resulted from limbal vernal keratoconjunctivitis and resected it for therapeutic purposes. Histopathological examination showed that eosinophils, lymphocytes, and fibroblasts were present in the subepithelial lesion and the substantia propria of the mass lesion. Immunohistochemical staining detected diffuse and rich infiltration of CD3-positive T lymphocytes and a relatively small number of CD20-positive B lymphocytes and CD138-positive plasma cells that tended to aggregate. The histopathologic features suggested that the limbal mass lesion had similar structures to the papillae at the tarsal conjunctiva of vernal keratoconjunctivitis. CONCLUSION: The limbal mass lesion as a finding of vernal keratoconjunctivitis can occur even if the papillae formation at the patient's tarsal conjunctiva is mild.

Long-Term Observation of Deep Anterior Lamellar Keratoplasty in Patients with Post-LASIK Granular Corneal Dystrophy Type 2: Two Case Reports.

INTRODUCTION: Laser-assisted in situ keratomileusis (LASIK) exacerbates granular corneal dystrophy type 2. Post-LASIK granular corneal dystrophy type 2 is treated by several surgical techniques. To the best of our knowledge, no report has addressed the results of deep anterior lamellar keratoplasty in affected patients. Here, we report our experience regarding deep anterior lamellar keratoplasty treatment of patients with post-LASIK granular corneal dystrophy type 2. METHODS: We describe two Japanese women who underwent deep anterior lamellar keratoplasty to treat corneal opacities that worsened after LASIK. RESULTS: One patient had a family history of corneal dystrophies. During the initial visit to our clinic, numerous fine opacities were found at the LASIK flap interface in both patients. The clinical findings were compatible with post-LASIK granular corneal dystrophy type 2. Both patients underwent deep anterior lamellar keratoplasty by one of the authors (T.C.). In both procedures, the surgeon used a visco-dissection technique and successfully removed the whole corneal stroma. Histopathological examination of the excised corneal button from each eye revealed amyloid and hyaline deposits at the LASIK flap interface. Neither patient experienced recurrent corneal opacity during the follow-up visit at 8 years (patient 1) and 6 years (patient 2). CONCLUSION: Deep anterior lamellar keratoplasty can be used for the treatment of post-LASIK granular corneal dystrophy type 2. Removal of the entire host stroma may be important for the prevention of recurrent corneal opacity.

Molecular characteristics of the photosensitizer TONS504: Comparison of its singlet oxygen quantum yields and photodynamic antimicrobial effect with those of methylene blue.

TONS504 (C51H58O5I2) is a chlorin derivative that exhibits a photodynamic antimicrobial effect (PAE) on various infectious keratitis pathogens. However, the molecular characteristics of TONS504 are not well understood. This study aimed to investigate the molecular characteristics of TONS504 by comparing its singlet oxygen (1O2) quantum yields and PAE with those of methylene blue (MB). To measure the 1O2 quantum yields, TONS504 and MB were dissolved in phosphate-buffered saline and phosphate-buffered saline containing 1% Triton X-100. The solutions were then activated by a Nd:YAG laser with an average output power of 8 mW. Near-infrared 1O2 luminescence was detected as an indicator of the 1O2 quantum yields. To evaluate the PAE, TONS504 and MB were activated by a light-emitting diode with a total light energy of 30 J/cm2. We compared the minimum molar concentration of each photosensitizer to show apparent PAEs on Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. TONS504 exhibited higher 1O2 quantum yields than MB in PBS/Triton X-100 but not in PBS. S. aureus and C. albicans were reduced by TONS504 at lower concentrations than by MB, but this was not the case for P. aeruginosa. Our results provide insight on the molecular characteristics of TONS504 and suggest that TONS504 has excellent 1O2 quantum yields and PAE. Compared with MB, TONS504 in PBS has stronger efficacy toward some infectious keratitis pathogens but not others.

A Case of Paracentral Corneal Perforation Treated with One-Bite Mini-Keratoplasty.

A 61-year-old man presented with corneal perforation of 1.0 mm in diameter in his right eye caused by a metallic foreign body fragment. We used the "one-bite mini-keratoplasty" technique, which uses a cornea patch with a single host-graft-host suture to stop aqueous humor leakage. Postoperatively, the graft was completely epithelialized. The suture was removed and the use of soft contact lens was discontinued. Postoperative best-corrected visual acuity (BCVA) recovered to 180/200 and corneal astigmatism was 0.6 diopters. The postoperative course was unremarkable, but corneal perforation recurred due to an ocular contusion at 17 months. He was reoperated using the same technique. His BCVA was 160/200 and corneal astigmatism was 1.1 diopters after reoperation. Despite performing this surgical technique twice for corneal perforation, optimal visual function was maintained even after 2 years. For paracentral corneal perforations, our simple technique may reduce astigmatism and maintain high visual function.

Efficacy of Photodynamic Anti-Microbial Chemotherapy for Acanthamoeba Keratitis In Vivo.

BACKGROUND AND OBJECTIVES: Acanthamoeba keratitis is a sight-threatening infectious disease that is difficult to treat. The aim of this study was to evaluate TONS504 (cationic chlorin derivative photosensitizer)-mediated photodynamic antimicrobial chemotherapy (PACT) in vivo as a potential treatment for Acanthamoeba keratitis. STUDY DESIGN/MATERIALS AND METHODS: Acanthamoeba keratitis was induced by soft contact lenses incubated with 1 × 105 /ml Acanthamoeba castellanii, which were placed over debrided corneas with temporary tarsorrhaphy. Thirty-eight male Japanese white rabbits were randomly divided into three groups (normal eye, no treatment, and treatment groups). TONS504 was administered as eye drops at 1 mg/ml, followed by light-emitting diode irradiation after the establishment of keratitis at 7 days after infectious contact lens exposure. All animals were evaluated under a slit-lamp microscope every 3 days for 6 days after the treatment. Clinical scores based on corneal epithelial defects detected by fluorescein staining, stromal opacity edema, and vascular infiltration into the cornea were determined. After 6 days, the eyes were enucleated for histopathological analysis. RESULTS: Clinical signs of infection in the treatment group were markedly reduced for up to 6 days after treatment. Histopathology showed a regular arrangement of stromal fibers and a small number of inflammatory cells in 58% of the corneas. However, 42% of corneas in the treatment group showed infiltrating neutrophils and irregular alignment of stromal collagen fibers. CONCLUSIONS: Our TONS504-PACT achieved complete recovery from keratitis in 58% of the rabbit models. Further studies are required to determine the conditions for the maximal effectiveness of our TONS504-PACT for Acanthamoeba keratitis. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Amantadine can induce intra-epithelial deposition in the cornea.

PURPOSE: Amantadine has been reported to cause various corneal complications, such as superficial punctate keratitis, corneal endothelial dysfunction, and corneal edema. However, there have been no reports of amantadine-induced deposits in the corneal epithelium. Here, we describe the first case with amantadine-induced deposits in the corneal epithelium proved by confocal biomicroscopy. OBSERVATIONS: An 81-year-old woman presented with impaired vision in both eyes. She had been treated with amantadine for 9 years. Corrected visual acuity was 0.8 in both eyes. Furthermore, both eyes showed opacities in the corneal epithelial corneal layer. On confocal biomicroscopy, there were highly reflective deposits in corneal epithelial cells. There were no pathological findings in the stroma and endothelium. Two months after discontinuation of amantadine, corneal opacities disappeared, and visual acuity was 1.0 in both eyes. CONCLUSIONS: Administration of amantadine can cause deposits in corneal epithelial cells.

Deep Neural Network-Based Method for Detecting Obstructive Meibomian Gland Dysfunction With in Vivo Laser Confocal Microscopy.

PURPOSE: To evaluate the ability of deep learning (DL) models to detect obstructive meibomian gland dysfunction (MGD) using in vivo laser confocal microscopy images. METHODS: For this study, we included 137 images from 137 individuals with obstructive MGD (mean age, 49.9 ± 17.7 years; 44 men and 93 women) and 84 images from 84 individuals with normal meibomian glands (mean age, 53.3 ± 19.6 years; 29 men and 55 women). We constructed and trained 9 different network structures and used single and ensemble DL models and calculated the area under the curve, sensitivity, and specificity to compare the diagnostic abilities of the DL. RESULTS: For the single DL model (the highest model; DenseNet-201), the area under the curve, sensitivity, and specificity for diagnosing obstructive MGD were 0.966%, 94.2%, and 82.1%, respectively, and for the ensemble DL model (the highest ensemble model; VGG16, DenseNet-169, DenseNet-201, and InceptionV3), 0.981%, 92.1%, and 98.8%, respectively. CONCLUSIONS: Our network combining DL and in vivo laser confocal microscopy learned to differentiate between images of healthy meibomian glands and images of obstructive MGD with a high level of accuracy that may allow for automatic obstructive MGD diagnoses in patients in the future.

Antimicrobial Photodynamic Therapy with the photosensitizer TONS504 eradicates Acanthamoeba.

BACKGROUND: Microbial keratitis is a potential cause of corneal blindness. We investigated the amoebicidal efficacy of photodynamic antimicrobial therapy with a light-emitting diode as the light source and the cationic chlorin derivative TONS504 as the photosensitizer for the elimination of Acanthamoeba, a causative organism of corneal infection and blindness. Acanthamoeba keratitis remains a challenge to treat because of limited available treatments. METHODS: Acanthamoeba castellani 50370 was exposed to TONS504 at various concentrations (0, 1, or 10 mg/L for trophozoites; 0, 1, 10, or 20 mg/L for cysts), irradiated at various light energies (0, 10, or 30 J/cm2 for trophozoites; 0, 30, or 60 J/cm2 for cysts), and incubated at 26 °C for 3 h. Assessment of cell viability by trypan blue staining revealed that photodynamic antimicrobial therapy attenuated the survival of trophozoites and cysts dependent on TONS504 concentration and light energy. RESULTS: Photodynamic antimicrobial therapy with 10 mg/L TONS504 and 30 J/cm2 light energy suppressed trophozoite viability by 77%, and 20 mg/L TONS504 and 60 J/cm2 light energy attenuated cyst survival by 42%. Staining with fluorescein isothiocyanate-conjugated annexin V and ethidium homodimer III revealed photodynamic antimicrobial therapy induced apoptosis and necrosis in trophozoites dependent upon the intensity of treatment, whereas apoptosis was the predominant form of cell death in cysts. CONCLUSIONS: Photodynamic antimicrobial therapy with TONS504 warrants further investigation as a potential treatment modality for Acanthamoeba keratitis.