Intraocular Implantable Collamer Lens with a Central Hole Implantation: Safety, Efficacy, and Patient Outcomes

This review summarizes the available literature and provides updates on the efficacy, safety, and patient outcomes of phakic intraocular lens implantation using implantable collamer lens (ICL), with a focus on newer models with a central port (EVO/EVO+ Visian Implantable Collamer Lens, STAAR Surgical Inc.). All studies included in this review were identified from the PubMed database and were reviewed for relevancy of their topic. Data on hole-ICL implantation performed between October 2018 and October 2022 in 3399 eyes showed a weighted average efficacy index of 1.03 and a weighted average safety index of 1.19 within an average follow-up of 24.7 months. The incidence of complications such as elevated intraocular pressure, cataract, and corneal endothelial cell loss was low. Moreover, both quality of vision and quality of life improved after ICL implantation, confirming the benefits of this procedure. In conclusion, ICL implantation is a promising refractive surgery alternative to laser vision correction with excellent efficacy, safety, and patient outcomes.

Clinical Characteristics, Histopathology, and Treatment Outcomes of Pythium Keratitis: A Retrospective Cohort Study

Purpose

To identify factors associated with the prognosis in Pythium keratitis.

Patients and Methods

The medical records of 25 patients (26 eyes) diagnosed with Pythium keratitis at a referral institution were reviewed. The demographic and clinical characteristics, treatment, microbiological diagnosis, histopathological features, and outcomes were recorded. The histopathological specimens were reviewed. The patients were divided into a globe removal group and a globe salvage group. Univariate analysis was used to identify factors associated with poor outcomes.

Results

Fifteen eyes (57.7%) were removed. Patients in the globe removal group were on average 16.4 years older (95% CI 6.98 to 25.88) than those in the globe salvage group, received the first medication (either topical antifungals or antibiotics) later than one day after the onset of symptoms (RR = 2.75, 95% CI 1.18 to 6.42), and had a maximal diameter of the infiltration area ≥6 mm (RR = 3.14, 95% CI 1.17 to 8.45). The globe removal group showed satellite, multifocal, or total corneal infiltration patterns (RR = 2.82, 95% CI 1.03 to 7.74) and a hypopyon (RR = 3.43, 95% CI 1.26 to 9.35) as risk factors. The histopathological examination showed a higher density of Pythium in the globe removal group than the globe salvage group (median 376 (interquartile range 323, 620) versus 107 (interquartile range 16, 260) hyphae per high power field; P = 0.035).

Conclusion

The risk of globe removal in patients with Pythium keratitis increased with age, delayed initial topical antifungal or antibiotic treatment, advanced disease at presentation, and dense Pythium hyphae infiltration of the cornea. Early recognition and treatment are critical to successfully eradicate the infection.

Prevention of recurrent pterygium with topical bevacizumab 0.05% eye drops: a randomized controlled trial

PURPOSE

We assessed the efficacy and tolerability of topical bevacizumab 0.05% when used as an adjunctive therapy after excision of primary pterygia.

METHODS

This randomized double-masked study included 22 patients (22 eyes) with primary pterygia who underwent pterygium surgery with the use of the bare sclera technique. After pterygium excision, 22 patients were randomized to receive the topical bevacizumab 0.05% (12 eyes) or the placebo (10 eyes) with the use of the block of four randomization method. Topical bevacizumab and placebo were applied in the respective groups 4 times daily for 3 months. Follow-up evaluations for recurrence by slit-lamp photography were conducted once monthly. Ocular and systemic adverse events were assessed every 2 weeks during the 3 months of treatment. The slit-lamp photographs were masked and analyzed. The primary and secondary outcomes were the differences in the pterygial recurrence rates between the groups and adverse events at 3 months, respectively. Corneal recurrence was defined as recurrent fibrovascular tissue invading the cornea; conjunctival recurrence was defined as either recurrent vessels or fibrous tissue in the excised area without corneal invasion.

FINDINGS

All 22 patients completed follow-up at 3 months after the start of the trial medications. After 3 months of treatment, 1 patient (8.33%) and 3 patients (30.00%) from the bevacizumab and placebo groups, respectively, had a corneal recurrence. No significant (P = 0.293) differences were found between the groups as determined by Fisher's exact test. However, conjunctival and corneal recurrences were found in 4 (33.33%) and 9 (90.00%) patients, respectively, in the bevacizumab and placebo groups, a difference that reached significance (P = 0.01). No significant adverse events developed.

IMPLICATIONS

Topical bevacizumab, as an adjunctive treatment after pterygium excision, was well tolerated. The trend for recurrence was lower in the topical bevacizumab group. ClinicalTrials.gov identifier: NCT01311960.

The Efficacy Between Conventional Lid Hygiene and Additional Thermal Pulsatile System in Meibomian Gland Dysfunction Patients Treated with Long-Term Anti-Glaucoma Medications in a Randomized Controlled Trial

Purpose

To evaluate the efficacy of additional thermal pulsatile system compared to standard lid hygiene alone in meibomian gland dysfunction (MGD) patients who are using long-term anti-glaucoma medications.

Patients and Methods

Well-controlled glaucoma patients who used anti-glaucoma medications for at least 1 year and had MGD were enrolled and randomized between a study group who received thermal pulsatile system (Lipiflow^®) treatment and standard lid hygiene, and a control group who received standard lid hygiene alone. The primary outcome was meibomian gland expression score, and the secondary outcomes were the Ocular Surface Disease Index (OSDI) score, Schirmer test score, tear break-up time (TBUT), corneal staining score, lipid layer thickness (LLT), and meibography score. All the outcomes were re-evaluated at 1 week, then at 1, 3, and 6 months after treatment.

Results

Of 60 participants who underwent randomization, 48 completed the study. At the 6-month mark, this study could not demonstrate any significant difference between groups in both primary and secondary outcomes. However, there was significant improvement from baseline in both groups of the following outcomes: meibomian gland expression score, OSDI score, LLT, and meibography score. No serious adverse event was found in this study.

Conclusion

An additional single thermal pulsatile system treatment with standard lid hygiene significantly improved meibomian gland assessment score and subjective symptoms at 6 months. Any difference between additional thermal pulsatile system treatment and lid hygiene alone was not found in this study. The results may suggest more chronic MGD and more damaged meibomian gland induced by long-term anti-glaucoma medications.

Case report: atypical presentation of Mycobacterium tuberculosis uveitis preceding nodular scleritis

Background

Intraocular tuberculosis is uncommon and has various clinical presentations. Lack of specific clinical clues can make the diagnosis challenging. The purpose of this study is to report a clinical presentation of tuberculous iridocyclitis that mimics phacolytic glaucoma and has a distinctive inflammatory deposit in the inner side of the cornea. This report is the first to describe the progression of tuberculous iridocyclitis to nodular scleritis without evidence for extraocular tuberculous infection.

Case presentation

A 78-year-old, immunocompetent woman presented with subacute intraocular inflammation with high intraocular pressure, mimicking phacolytic glaucoma. Distinct pigment keratic precipitates were noted on the first visit. Even though the cataract extraction was uneventful and adequate anti-inflammatory drugs were given, the inflammation did not subside as expected. Seven weeks later, she developed two scleral abscesses, which were subsequently explored for microbiological investigation. The smears of the pus revealed positive acid-fast bacilli stain and PCR for Mycobacterium tuberculosis complex. Eventually, the pus culture grew Mycobacterium tuberculosis. Anti-tuberculosis medications were prescribed. After 1 month of treatment, the abscesses were cured. However, her visual acuity did not improve at the last visit.

Conclusions

This case revealed an unusual presentation and untreated course of tuberculosis iridocyclitis. Pattern of keratic precipitates may indicate the presence of tuberculosis.

Rate of Cornea Endothelial Cell Loss and Biomechanical Properties in Fuchs' Endothelial Corneal Dystrophy

Background: Our study aimed to determine the correlation between the clinical staging of Fuchs' endothelial corneal dystrophy (FECD), rate of endothelial cell loss, and corneal biomechanical properties. Methods: This study combined a longitudinal retrospective/prospective analysis of corneal endothelial cell loss and a prospective cross-sectional analysis of corneal biomechanics of Fuchs' endothelial dystrophy. The trial was registered at the Thai Clinical Trials Registry as TCTR 20160927004. FECD was diagnosed by the presence of corneal guttata detected by slit lamp microscopy; the disease severity was classified into four stages using the modified Stocker's classification. In vivo confocal microscopy, Scheimpflug imaging, and Corneal Visualization Scheimpflug Technology were performed to evaluate endothelial cell count, central corneal thickness, and corneal biomechanical properties. Linear mixed modeling analyses were used to estimate the endothelial cell densities in a 4-year period. The corneal biomechanics were compared among the stages using Corvis ST parameters. Results: Eighty eyes from eighty subjects were enrolled (42, 26, 12, and none in stages 1, 2, 3, and 4, respectively). The mean endothelial cell density was 1228.35 cells/mm². The year-by-year reduction rate was 94.3 cells/mm² (μ_EMM = -94.3, 95% CI: -115.4 to -73.2, p < 0.001). Corneal endothelial cell losses in Fuchs' endothelial dystrophy were estimated to be 7.7, 7.8, and 8.4% per year for stages 1, 2, and 3, respectively. The mean corneal thicknesses of stages 1, 2, and 3 were 556 ± 32, 623 ± 33, and 648 ± 50 mm, respectively. For the corneal biomechanical parameters, the A1-length and A1-time were significantly different between stages 1 and 3 (A1-length: mean diff_stage1vs.3 = 0.10, 95% CI: < 0.001-0.15, p < 0.001, A1-time: mean diff_stage1vs.3 = -0.24, 95% CI: -0.41 to -0.07, respectively). Conclusions: In the advanced stage, corneas significantly changed their biomechanical viscoelastic behavior by decreasing resistance, as measured by a longer A1-length and shorter A1-time.

The efficacy and safety of 0.5% Levofloxacin versus fortified Cefazolin and Amikacin ophthalmic solution for the treatment of suspected and culture-proven cases of infectious bacterial keratitis: a comparative study

Background: Bacterial keratitis is a major devastating ocular condition that quickly deteriorates the patient’s vision. Vigorous and prompt treatment of bacterial keratitis with broad-spectrum antibiotic eye-drops is preferred.

Objective: Evaluate the efficacy and safety of 0.5% Levofloxacin for the treatment of suspected and cultureproven cases of infectious bacterial keratitis in comparison to fortified Cefazolin and Amikacin ophthalmic solution.

Materials and methods: Seventy-one eyes from 69 patients suspected of having infectious bacterial keratitis were enrolled in the study. The patients were randomized into two arms, 0.5% Levofloxacin eye drops (34 eyes) or fortified Cefazolin and Amikacin (37 eyes). Sixty-eight eyes were included in the efficacy analysis. During treatment, on days 2, 7, 14, and 21, the patient’s symptoms and signs were scored from grade 0-3 (absent to severe).

Results: At the end of the treatment, 61 out of 71 eyes completely healed. The resolution of the keratitis was not significantly different between both groups. There were no significant differences in the mean time-duration for the ulcer to heal or for the symptoms and clinical signs to disappear between the two groups. No serious adverse events or side effects from the disease were found. The patients compliance was 80% based on the self-reported diaries.

Conclusion: The efficacy and safety of 0.5% topical Levofloxacin was comparable to fortified Cefazolin and Amikacin for the treatment of mild-to-moderate bacterial keratitis. Topical Levofloxacin is far superior because of its availability and patient compliance when used as monotherapy for the treatment of infectious bacterial keratitis.

Prevalence of dry eye disease in autoimmune thyroid disease and the association of dry eye with clinical signs of thyroid associated ophthalmopathy: observational, noncomparative, cross-sectional study

Background

Autoimmune thyroid disease (AITD) is a risk factor for dry eye disease. The prevalence of dry eye in AITD is not definitely known.

Objectives

To determine the prevalence of dry eye in AITD and its association with clinical signs of thyroid associated ophthalmopathy (TAO).

Methods

We enrolled a cross-section of 92 patients with AITD between May 1 and August 31, 2013. All were examined to establish thyroid eye signs, and severity was classified as none, mild, and moderate-severe according to the European Group on Graves’ orbitopathy. Dry eye disease was verified using an Ocular Surface Disease Index (OSDI) questionnaire, tear break-up time (TBUT), Schirmer test, and ocular surface fluorescein staining. Features of meibomian glands were inspected. This observational study was registered at www.clinicaltrials.in.th, No. TCTR20130713001.

Results

The prevalence of dry eye in AITD was 27% by OSDI questionnaire (95% confidence interval (CI), 16%-34%); 96% (95% CI, 93%-99%) by TBUT; 69% (95% CI, 62%-75%) by ocular surface staining; and 18% (95% CI, 12%-23%) using a Schirmer test, which associated dry eye and proptosis with an odds ratio (OR) of 9.3 (95% CI, 1.2-70.6, P = 0.031), and lagophthalmos by ocular surface staining with an OR of 5.8 (95% CI, 1.2-27.7, P = 0.026). Dry eye in patients with or without clinical signs of TAO was not significantly different.

Conclusions

The prevalence of dry eye varied by criteria, but was not different in AITD patients with or without TAO. Proptosis and lagophthalmos were associated more strongly with dry eye disease in AITD with TAO, than without.

Topometric Indices And Corneal Densitometry Change After Corneal Refractive Surgery Combined With Simultaneous Collagen Crosslinking

Purpose

To show the alteration of tomography, topometric indices and corneal densitometry after corneal refractive surgery combined with collagen crosslinking.

Patients and methods

All medical records of patients undergoing corneal refractive surgery with simultaneous collagen crosslinking during April 2015 and August 2018 were retrospectively reviewed. Corneal tomography, higher-order aberrations (HOA), topographic indices and corneal densitometry were evaluated. All the data at 1 month, 3 months and 6 months were compared to baseline value. All complications were noted. P value less than 0.05 was considered statistically significant.

Results

Medical records of fourteen patients (twenty-five eyes) were reviewed. HOA increased at all time points (p < 0.05). Keratoconus index and central keratoconus index decreased, whereas index of surface variance, index of vertical asymmetry, index of height decentration and the minimum of radius of curvature increased at all time points (p < 0.05). Index of height asymmetry increased at 3 and 6 months (p < 0.05). Corneal densitometry at anterior layer of 0–10 mm zone and center layer of 0–6 mm zone increased at 1 and 3 months (p < 0.05). At 6 months, the densitometry at 0–6 mm zone returned to baseline level. However, at 6 months, at anterior and center layer of 6–10 mm zone, the densitometry values were still more than preoperative values (p < 0.05). There was one case of bacterial keratitis.

Conclusion

After the corneal refractive surgery combined with collagen crosslinking, the HOA and corneal densitometry increased. Topographic indices showed conflicting results.

Comparison of performances of femtosecond laser and microkeratome for thin-flap laser in situ keratomileusis

OBJECTIVE

To compare the clinical outcomes of femtosecond laser (FS) and microkeratome (MK) for thin-flap in situ keratomileusis (LASIK).

MATERIALS AND METHODS

Data from patients with moderate to high myopia (spherical equivalent, >-4 diopters [D]) who underwent thin-flap LASIK using FS (199 eyes/110 patients) and MK (157 eyes/86 patients) were analyzed in this retrospective study. Preoperative and postoperative data were recorded from day 1 and months 1 and 3, postoperatively. Visual and refractive outcomes were compared for efficacy, safety, predictability, stability, and the efficacy and safety indices.

RESULTS

Three months postoperatively, more eyes in the FS group had an uncorrected distance visual acuity (UCVA) of 20/40 or better compared to MK group (relative risk [RR] 1.01, 95% confidence interval [CI], 0.97-1.05, P = 0.58); significantly more eyes in FS group had an UCVA of 20/20 or better (RR, 1.26, 95%CI, 1.08-1.48, P = 0.003). Intraoperative bleeding occurred in 5% and 36.7%, respectively, of FS and MK groups. There were no significant differences in the refractive predictability within spherical equivalents of 0.5 D (FS, 72%; MK, 63%) and 1.0 D (FS, 90%; MK, 86%). Both groups showed good stability 3 months, postoperatively. The efficacy index in FS group was 113.4%; that in MK group was 102.5% at 3 months postoperatively (P < 0.05). The safety indices for FS and MK groups at 3 months postoperatively were 116.4% and 108.2%, respectively (P < 0.05).

CONCLUSIONS

Both methods of thin-flap created LASIK were effective, safe, predicable, and stable. FS group had significant improvements in efficacy and safety, confirmed by the efficacy and safety indices, compared to MK group. Lasers Surg. Med. 48:596-601, 2016. © 2016 Wiley Periodicals, Inc.

Recurrent rates and risk factors associated with recurrent painful bullous keratopathy after primary phototherapeutic keratectomy

OBJECTIVE

To assess the recurrent rate, mean survival time, and risk factors associated with recurrent painful bullous keratopathy (BK) after primary treatment with phototherapeutic keratectomy.

METHODS

Medical records from 72 patients (72 eyes) who had phototherapeutic keratectomy for painful BK were evaluated. Data for sex, age, duration of BK, associated ocular and systemic diseases (hypertension, diabetes mellitus, ischemic heart disease, asthma, dyslipidemia, and rheumatoid arthritis), frequency and degree of pain (grade 1-3), visual acuity, corneal thickness, intraocular pressure, and laser setting were extracted and analyzed.

RESULTS

The mean age of the patients was 64.2±11.4 years. The mean preoperative duration of BK was 15.0±11.0 months. Most patients had pseudophakic BK (69.40%). Majority of the cases had grade 3 degree of pain (48.60%). Glaucoma and hypertension were markedly found among these patients (51.40% and 19.40%, respectively). Preoperative mean intraocular pressure and corneal thickness were 13.70±4.95 mmHg and 734.1±83.80 µm, respectively. The mean laser diameter and depth were 8.36±1.22 mm and 38.89±8.81 µm, respectively. Systemic disease was significantly associated with the risk for developing recurrent painful BK (P=0.022, hazard ratio [HR] 1.673, 95% confidence interval [CI] 1.08-2.58). The overall recurrent rate was 51%. The average duration time of recurrent painful BK was 17.3±12.9 months (range 1-50 months). The median survival time before recurrence was 29.0±6.6 months.

CONCLUSION

Systemic disease was found to be the only risk factor significantly associated with the development of recurrent painful BK. Low recurrent rate and long mean survival time showed that phototherapeutic keratectomy was effective in relieving recurrent painful BK and can be used as an alternative procedure for patients waiting for corneal transplantation.

Descemet's scroll in syphilitic interstitial keratitis: a case report with anterior segment evaluation and a literature review

Purpose

To present a case of syphilitic interstitial keratitis with Descemet’s scrolls, as well as its characteristic findings in an anterior segment investigation in relation to the histopathologic findings from a literature review.

Case presentation

A case report of a 64-year-old woman with syphilitic infection presented with band keratopathy and retrocorneal scrolls. Slit-lamp photography, confocal microscopy, anterior segment optical coherence tomography (AS-OCT), and ultrasound biomicroscopy were performed. Four previous reports were reviewed to describe the pathogenesis, natural history, and histopathologic and immunohistologic findings of the Descemet’s scroll.

Results

The spectacle-corrected visual acuity was 20/50 and 20/30 in the right and left eyes, respectively. The scrolls appeared as a translucent web extending from Descemet’s membrane into the anterior chamber. Confocal microscopy showed decreased endothelial cell density, pleomorphism, polymegathism, and hyperreflective fibrocellular rods with central hollow. The AS-OCT and ultrasound biomicroscopy showed rod-shaped retrocorneal scrolls. The corneal thickness was 494 microns, as measured by AS-OCT. The corneal lesion remained stable during the 6-year follow-up period without the need for keratoplasty, while the previous literature reported spontaneous and postoperative corneal decompensation.

Conclusion

We present a case of syphilitic interstitial keratitis with rare Descemet’s scrolls featuring relatively good visual acuity. Although we did not obtain the corneal tissue for examination, the anterior segment investigation provides insight into the underlying histopathology and natural disease history. The central hollow and cellular component seen during confocal microscopy might correspond to the amorphous core and the abnormal endothelial cells in the histopathologic findings. Failure to detect the corneal endothelium due to stromal opacity in these cases is possible, however, compromised endothelium may present.

Effectiveness of voriconazole and corneal cross-linking on Phialophora verrucosa keratitis: a case report

Background

We report a rare case of Phialophora verrucosa fungal keratitis, which required various types of treatment according to the intractable natural history of the disease.

Case presentation

A 51-year-old Thai man with poorly controlled diabetes received a bamboo branch injury and developed a perforated corneal lesion on his left eye. A pathological study from therapeutic penetrating keratoplasty showed fungal hyphae. This was later identified as Phialophora verrucosa by polymerase chain reaction. This organism was aggressive and recalcitrant because it relapsed with two corneal grafts and was resistant to amphotericin B, natamycin, and itraconazole. However, we found that the efficacy of voriconazole was promising for treating Phialophora verrucosa. We also used corneal cross-linking to establish corneal integrity after the infection was under control.

Conclusions

Because of the chronic nature of Phialophora verrucosa, a patient’s first visit may occur many years after trauma, and sometimes clinical presentation might not appear to indicate fungal infection. Therefore, a high index of suspicion is needed in this situation. Voriconazole showed good results in our case. Instead of using a more invasive keratoplasty, we used corneal cross-linking to strengthen the corneal biomechanics. To the best of our knowledge, this is the first case showing the benefit of corneal cross-linking to improve corneal biomechanics in resolved Phialophora verrucosa keratitis.

Prevalence of Human Papillomavirus Genotypes in Pterygia from Thai Individuals

Purpose: Pterygium, a common ocular growth, has an unknown pathogenesis and aetiology. Environmental factors such as ultraviolet light, genetic factors and viral infections may be implicated in the development of pterygia. Human papillomavirus (HPV), an oncogenic virus, has previous been detected in individuals with pterygia. The aim of this study was to assess the prevalence of HPV genotypes in pterygia from Thai individuals.Methods: DNA was extracted from 389 pterygia. HPV was detected by nested PCR and HPV genotyping was conducted using reverse hybridization. The DNA sequences of HPV-L1 genes were analyzed.Results: HPV was detected in only 6.8% (25/389) of pterygia from Thai individuals. The majority (16/25, 64%) of strains were genotyped as HPV-16 and the remainder (9/25, 36%) could not be typed. Four pterygia showed evidence of coinfection by HPV-16 and either HPV-18 (2/25, 8%) or HPV-58 (2/25, 8%). Nine of 11 samples showed the same HPV-16 L1 gene sequence that was identical to a HPV-16 reference sequence in GenBank. The remaining two samples each bore silent single nucleotide mutations (T1078G and T1081A) that did not result in amino acid changes.Conclusion: HPV, especially HPV-16, may be one of the pathogens causing pterygia in Thai individuals. Genotyping data suggested that HPV-16 from pterygia may be similar in sequence to HPV-16 causing cervical cancer.

Survival Outcome and Prognostic Factors of Corneal Transplantation: A 15-Year Retrospective Cohort Study at King Chulalongkorn Memorial Hospital

Purpose

To evaluate long-term survival outcomes and determine the prognostic factors of corneal transplantation performed at a tertiary referral hospital in Thailand.

Design

A 15-year retrospective cohort study.

Materials and Methods

One corneal graft per patient was selected; graft failure was defined as graft opacity due to recurrent disease or endothelial cell dysfunction. Kaplan–Meier survival analysis was performed. Median time to failure was compared using the Log rank test. Prognostic factors were identified using the Cox proportional hazards model.

Results

We enrolled 704 transplanted grafts. Surgical indications were optical (88.5%), therapeutic (10.2%), and tectonic (1.3%). The most common diagnoses were corneal opacity (25.3%), bullous keratopathy (15.8%), and regraft (14.8%). The overall survival rates at 1, 3, 5, and 10 years were 87.5%, 72.0%, 59.2%, and 41.7%, respectively. Univariate analysis identified age, primary diagnosis, graft size, pre-existing glaucoma, prior lens status, prior intraocular surgery, indication for surgery, donor endothelial cell density, and previous graft rejection as prognostic factors for graft failure. Multivariate analysis revealed three prognostic factors: primary diagnosis of perforation/peripheral ulceration/Mooren’s ulcer (hazard ratio [HR]=28.57; 95% confidence interval [CI], 6.32–129.16; P<0.001), active keratitis (HR=24.30; 95% CI, 5.88–100.43; P<0.001), regraft (HR=9.37; 95% CI, 2.27–38.66; P=0.002), and pseudophakic/aphakic bullous keratopathy (HR=7.97; 95% CI, 1.93–32.87; P=0.004); pre-existing glaucoma (HR=1.52; 95% CI, 1.13–2.04; P=0.006); and previous graft rejection (HR=1.95; 95% CI, 1.54–2.48; P<0.001).

Conclusion

Overall corneal graft survival rate was high in the first postoperative year and decreased after that. Primary diagnosis, pre-existing glaucoma, and previous graft rejection negatively influenced graft survival.

Keratoconus in Thai population - a cross-sectional hospital-based study

Background

Studies in the epidemiology of keratoconus are limited in Southeast Asia. A study on the prevalence and characteristics of keratoconus in the Thai population could give a general idea of its impact.

Objectives

To study keratoconus prevalence in patients seeking refractive surgery and analyze the characteristics of keratoconus.

Methods

Medical records from April 2015 to August 2018 were retrospectively reviewed. Keratoconus and keratoconus suspect prevalence in patients seeking laser vision correction were calculated. The characteristics of keratoconus patients were reviewed. The Amsler-Krumeich classification was used to determine the stages. Topographically, the types of cones were categorized into oval, nipple, pellucid marginal degeneration (PMD)-like, and astigmatic types.

Results

Keratoconus and keratoconus suspect prevalence were 1.66% and 0.68%, respectively. Out of the affected patients, 73.8% were male. The mean age at diagnosis was 25.25 ± 8.35 years. The presenting symptoms were blurred vision (87%) and itching (47%). Stage 1 was predominant, found in 39% of patients (followed by stages 2, 4, and 3, respectively). Ocular findings comprised the Munson sign (14.63%), the Rizutti sign (6.94%), Fleischer ring (28.14%), Vogt striae (24.95%), corneal scar (8.63%), prominent corneal nerve (2.81%), and corneal staining (7.69%). Mean uncorrected visual acuity (logarithm of the minimum angle of resolution [logMAR]) was 0.88 ± 0.64. Mean corrected visual acuity (logMAR) was 0.40 ± 0.49. Mean Q-value was -0.92 ± 0.63. The thinnest pachymetry was 459.39 ± 56.96 microns. The mean keratometry was 49.7 ± 6.64 diopters. Topographically, the types of cones were oval (57%), astigmatic (33%), PMD-like (5%), and nipple type (4%).

Conclusions

Keratoconus prevalence among Thai patients seeking refractive surgery was 1.66%. Most patients were male and presented with the disease at a mild bilateral stage in their second decade of life.

Deep Learning Algorithm for Keratoconus Detection from Tomographic Maps and Corneal Biomechanics: A Diagnostic Study

Purpose

To develop an artificial intelligence (AI) approach for differentiating between normal cornea, subclinical, and keratoconus (KC) using tomographic maps from Pentacam (Oculus) and corneal biomechanics from Corvis ST (Oculus).

Methods

A total of 1,668 tomographic (769 patients) and 611 biomechanical (307 patients) images from the Chula Refractive Surgery Center, King Chulalongkorn Memorial Hospital were included. The sample size was divided into the Pentacam and combined Pentacam-Corvis groups. Different convolutional neural network approaches were used to enhance the KC and subclinical KC detection performance.

Results

AI model 1, which obtained refractive maps from Pentacam, achieved an area under the receiver operating characteristic curve (AUC) of 0.938 and accuracy of 0.947 (sensitivity, 90.8% and specificity, 96.9%). AI model 2, which added dynamic corneal response and the Vinciguerra screening report from Corvis ST to AI Model 1, achieved an AUC of 0.985 and accuracy of 0.956 (sensitivity, 93.0% and specificity, 94.3%). AI model 3, which added the corneal biomechanical index to AI Model 2, reached an AUC of 0.991 and accuracy of 0.956 (sensitivity, 93.0% and specificity, 94.3%).

Conclusions

Our study showed that AI models using either anterior corneal curvature alone or combined with corneal biomechanics could help classify normal and keratoconic corneas, which would make diagnosis more accurate and would be helpful in decision-making for the treatment.

The prevalence of corneal guttata and its related risk factors in a Thai population: a community-based study in central Thailand

This is a large cross-sectional, population-based survey to investigate the prevalence of central corneal guttata in the Thai population. Two communities in the central region of Thailand are (1) Phanat Nikhom district, Chonburi, and (2) Khlong Toey district, Bangkok. All participants completed an interview and ophthalmic examination. Overall, 990 participants aged ≥ 40 years were included. The prevalence of central corneal guttata was 40.80% (399/978 participants); 328/978 participants (33.54%) exhibited modified Krachmer grade I corneal guttata. The study utilized definitive diagnosis and severity grading, using the modified Krachmer grading scale, to estimate the prevalence within the general population and to identify potential risk factors. The presence of central corneal guttata was evaluated by three corneal specialists (VP, VS, and PP) using a slit-lamp biomicroscope and the NIDEK CEM-530 specular microscope (NIDEK, Aichi, Japan). The estimated overall prevalence in the Thai population was 45.76%, with an approximate female-to-male ratio of 1.35:1. Multiple logistic regression analysis showed that only age ≥ 50 years, compared with age 40-49 years, was a significant risk factor for the presence of central corneal guttata. In conclusion, this study showed that the prevalence of central corneal guttata (mainly sporadic cases) in the Thai population was as high as 45.76%.

Efficacy of Interleukin-1β Inhibitor on Dry Eye Disease in Patients with Degenerative Arthritis

Purpose

To evaluate diacerein (interleukin-1β inhibitor) efficacy on ocular surface disease (OSD).

Patients and Methods

This prospective observational study included patients who received diacerein for osteoarthritis and had dry eye (DE). The primary outcome was corneal staining score. Secondary outcomes were ocular surface disease index (OSDI) score, tear breakup time (TBUT), tear osmolarity (Osm), Schirmer's test results, interleukin-1α (IL-1α), interleukin-1β (IL-1β), and interleukin-1 receptor antagonist (IL-1Ra) levels in tears. All measurements were done at baseline and 2-month follow-up visits. Linear mixed models were used to examine the effect of all parameters, and log-transformed models were used for IL-1α, IL-1β, and IL-1Ra analyses.

Results

Thirty-four patients (31 females and 3 males) were enrolled. The corneal staining score improved by 1.29 points (P=0.022, 95% confidence interval [95% CI] 0.19 to 2.40) after 2 months, and the OSDI score improved by 17.2 points (P<0.001, 95% CI 10.82 to 23.58) but TUBT decreased by 0.66 seconds (P=0.021, 95% CI 0.10 to 1.22). No significant differences were observed in the tear Osm and Schirmer's test. IL-1Ra demonstrated no statistical difference, IL-1α was significantly increased by 80% (P=0.260), and IL-1β was significantly decreased by 99.21% (P<0.001).

Conclusion

Diacerein can improve corneal staining and decrease IL-1β levels in tears, which reflects better DE symptoms. Diacerein may be a promising alternative treatment for patients with OSD and osteoarthritis.

Effectiveness and Safety of Combined Application of Three Modes of 2940-nm Erbium:YAG and 1064-nm Neodymium:YAG Lasers in Treatment of Meibomian Gland Dysfunction

Purpose

To study the effectiveness and safety of upper and lower eyelid treatment with combined application of three modes of 2940-nm erbium-doped yttrium aluminium garnet (Er:YAG) and 1064-nm neodymium-doped yttrium aluminium garnet (Nd:YAG) lasers in patients with baggy eyelids (formed by intraorbital fat herniation) who exhibited meibomian gland dysfunction (MGD).

Patients and Methods

In this prospective cohort study, patients with baggy eyelid who exhibited MGD received combined laser treatment at baseline, as well as at the 4-, 8-, and 12-week follow-ups. The primary endpoint was meibum quality score at 16- and 24-week follow-ups; secondary endpoints were ocular surface index scores, tear film lipid layer thicknesses, tear break up times (TBUTs), Oxford scheme grades, and meibography grades at 16- and 24-week follow-ups. Adverse events, uncorrected visual acuities, best-corrected visual acuities, and intraocular pressures were also recorded.

Results

Sixteen patients (four men and 12 women; mean age, 56.38 ± 8.64 years) were included. Meibum quality scores at the 16-week follow-up were significantly lower than scores at baseline (p=0.043) and at the 24-week follow-up (p=0.015). TBUT was significantly exacerbated at the 24-week follow-up, compared with baseline (p=0.001) and the 16-week follow-up (p=0.006). There were no significant changes in other parameters. All adverse events were mild and resolved without additional treatment.

Conclusion

Combined application of three modes of 2940-nm Er:YAG and 1064-nm Nd:YAG lasers on upper and lower eyelids significantly improved meibum quality in patients with MGD; it ameliorated symptoms and signs of dry eye disease at 4 weeks after completion of laser treatment.

Penetrating keratoplasty versus deep anteriror lamellar keratoplasty for macular corneal dystrophy: A meta-analysis

STUDY DESIGN

We assessed the efficacy of deep anterior lamellar keratoplasty (DALK) and penetrating (PK) for macular corneal dystrophy (MCD) We searched on 4 databases for articles published up to the end of April, 2024. The study's outcome was postoperative visual acuity and other factors that may affect visual outcomes (e.g., spherical equivalent and postoperative complications). Meta-analysis was performed using random-effects or fixed-effect model according to the heterogeneity. We included 6 studies (1 RCT and 5 retrospective studies) comparing DALK (139 eyes) and PK (507 eyes) for MCD. No significant differences were found between the 2 procedures in uncorrected visual acuity, best-corrected visual acuity, and spherical equivalent (p = 0.58, 0.11 and 0.2, respectively). The risk of graft rejection was significantly higher in the PK group than in the DALK group (RR = 0.33; P = 0.001); however, MCD recurrence results were considerably higher in the DALK group than in the PK group (RR = 2.69, p < 0.001). The risk ratio for complications and graft survival have no significant difference between the two interventions (p = 0.9 and 0.62, respectively). Among the studies reviewed, 5 had a moderate risk of bias, while the remaining had a high risk. Our results showed that both PK and DALK have comparable outcomes of postoperative visual acuity, spherical equivalent, graft survival, and complication rate when treating MCD. Although the PK group had a higher rate of graft rejection, the DALK group had a higher recurrence rate.

Efficacy of local conjunctival immunotherapy in allergic conjunctivitis

BACKGROUND

Allergic conjunctivitis was a chronic inflammatory disease, usually associated with rhinitis. Several modalities of treatment were available, but few studies mentioned of immunotherapy which might had benefits in chronic and severe cases.

OBJECTIVE

To evaluate efficacy and safety of local conjunctival immunotherapy (LCIT) using a mixed Dermatophagoides extracts for treatment of allergic conjunctivitis (AC) METHODS: A prospective, double-blind and randomized controlled trial (RCT) was performed on eighteen patients with positive skin prick test (SPT) reactions to house dust mites. They were randomized into 2 groups: 1) treated with LCIT and 2) treated with balanced salt solution (BSS) as a control for a 6-month period. Allergen extracts were prepared in eyedrops and given once daily in LCIT group. Efficacy was assessed by clinical scores and conjunctival provocation test (CPT).

RESULTS

At 6 months, the CPT scores for the LCIT group reached statistical significance compared to the control group (p = 0.038), but there were no statistically significant differences in signs (p = 0.591), symptoms (p = 0.885) and medication scores (p = 0.338) between both groups. Patients in LCIT group were able to tolerate the allergen without developing any serious adverse events.

CONCLUSION

LCIT treatment significantly reduced CPT scores which indicated that the patients were able to tolerate the antigen better than their counterparts. However, LCIT alone at short period did not alleviate symptoms and signs of allergic conjunctivitis from multiple allergens.

Anti-inflammatory effect of curcuminoids and their analogs in hyperosmotic human corneal limbus epithelial cells

BACKGROUND

To assess the efficacy of curcuminoids (curcumin, demethoxycurcumin, bisdemethoxycurcumin [BDC]) and their analogs (tetrahydrocurcumin [THC], tetrahydrodemethoxycurcumin [THDC], tetrahydrobisdemethoxycurcumin) in reducing inflammatory cytokines and their toxicity to primary human corneal limbal epithelial cells, these cells were cultured and exposed to these compounds.

METHODS

The PrestoBlue assay assessed cell viability after treatment. Anti-inflammatory effects on hyperosmotic cells were determined using real-time polymerase chain reaction and significance was gauged using one-way analysis of variance and Tukey's tests, considering p-values < 0.05 as significant.

RESULTS

Curcuminoids and their analogs, at 1, 10, and 100 µM, exhibited no effect on cell viability compared to controls. However, cyclosporin A 1:500 significantly reduced cell viability more than most curcuminoid treatments, except 100 µM curcumin and BDC. All tested curcuminoids and analogs at these concentrations significantly decreased mRNA expression levels of tumor necrosis factor-α, interleukin (IL)-1β, IL-6, IL-17 A, matrix metallopeptidase-9, and intercellular adhesion molecule-1 after 90 mM NaCl stimulation compared to untreated cells. Furthermore, proinflammatory cytokine levels from hyperosmotic cells treated with 1, 10, and 100 µM curcumin, 100 µM BDC, 100 µM THC, 1 and 100 µM THDC mirrored those treated with cyclosporin A 1:500.

CONCLUSION

The anti-inflammatory efficiency of 1 and 10 µM curcumin, 100 µM THC, 1 and 100 µM THDC was comparable to that of cyclosporin A 1:500 while maintaining cell viability.

Factors predicting the visual outcome of intracorneal ring segment for keratoconus

OBJECTIVES

To identify predictive factors and to construct predictive models using epidemiological and clinical preoperative factors for the visual acuity change after intracorneal ring segment (ICRS) implantation in patients with keratoconus.

METHODS

The medical records of 287 keratoconic eyes of 230 patients implanted with ICRS at Chula Refractive Surgery Center of a tertiary university hospital (Bangkok, Thailand) between January 2012 and March 2022 were retrospectively reviewed for epidemiological and clinical preoperative variables, including those derived from Scheimpflug tomography. After randomly excluding one eye for each bilateral case, the remaining 230 eyes were randomized into two groups: a training group (184 eyes) and a validation group (46 eyes). In the training group, the correlation between the interesting variables and postoperative uncorrected and corrected distance visual acuity change (ΔUDVA and ΔCDVA; logMAR scale) at 6 months was explored, and then the multiple linear regression analysis was used to develop the predictive models. The obtained models were tested using the validation group.

RESULTS

There were 5 and 14 preoperative variables that statistically correlated with ΔUDVA and ΔCDVA respectively. Only the preoperative corrected distance visual acuity (CDVAp) strongly correlated with ΔCDVA (Beta = -0.746). Using multiple regression, the preoperative uncorrected distance visual acuity (UDVAp) and front mean keratometry were selected in the proposed model for ΔUDVA (adjusted R2 = 38.8%), while the CDVAp and index of surface variance (ISV) were selected in the model [Formula: see text] (adjusted R2 = 48.9%). The ΔUDVA and ΔCDVA models were correct in 47.83% and 63.4% of the validation group within 0.20 logMAR, respectively.

CONCLUSIONS

Potential predictive factors and models for ICRS-induced changes in visual acuity are proposed as adjunctive tools for clinicians. Such tools could be used for case selection and during counselling before ICRS implantation to maximize surgical outcomes.