Anterior Segment Optical Coherence Tomography Research Articles

Diagnostic utility of tear meniscus height measurement using anterior segment optical coherence tomography for lacrimal passage disorder before cataract surgery

To evaluate diagnostic utility of tear meniscus height (TMH) measurement using anterior segment optical coherence tomography (AS-OCT) for lacrimal passage disorder (LPD) in patients scheduled for cataract surgery. Patients with cataracts were enrolled. Lacrimal irrigation test was used to diagnose LPD. TMH measurement was performed using prior to cataract surgery. A receiver operating characteristic curve analysis was performed to calculate the cutoff value of TMH to detect LPD. Correlation between TMH and age, sex, LPD, use of glaucoma eyedrops, and use of dry eye drops in patients with and without LPD was evaluated. Sixty-six patients (127 eyes) were included, of which 12 (9.4%) eyes had LPD. The mean TMH was significantly higher in the LPD group than in the non-LPD group (P = 0.007). Multiple regression analysis revealed a significant association of TMH with LPD (P = 0.000). With an area under the curve of 0.740, the optimal cut-off TMH value was 401.0 μm. The sensitivity and specificity of this cutoff value were 58.3% and 83.0%, respectively. These findings demonstrate the diagnostic utility of TMH, measured using AS-OCT, for LPD. This suggests that AS-OCT is useful for preoperative exclusion of LPD.

Short-term changes in the trabecular iris angle and anterior chamber during wear of scleral lenses with different diameters

ABSTRACT Clinical relevance Scleral lens (SL) compression on the conjunctiva/episclera during wear may alter adjacent structures related to aqueous humour drainage. Background The aim of this work was to assess short-term changes in the four quadrants of trabecular iris angle (TIA) and anterior chamber parameters during SL wear, using anterior segment optical coherence tomography (AS-OCT). Methods Prospective study was conducted involving 16 healthy subjects with a mean age of 28 ± 5 years. Two SL of diameter 15.80 mm (L1) and 16.80 mm (L2) with the same parameters were used for 2 hours in different days. The central fluid reservoir (FR), the TIA in superior, inferior, nasal, temporal quadrants, and anterior chamber parameters; anterior chamber depth (ACD), anterior chamber width (ACW), anterior chamber area (ACAr) and anterior chamber volume (ACV) were measured with AS-OCT. These measurements were performed immediately after SL application (0 h), one hour (1 h) and two hours (2 h) of SL wear. Results TIA decreases significantly in the superior quadrant at 2 hours of L2 wear (−5.19 ± 7.79º) (p = 0.04). In this sector, differences were also observed between the changes induced by both lenses during the 2 hours of wear (p = 0.04) and between first and second hours of wear (p = 0.04). ACD was significantly lower with L1 (−0.09 ± 0.14 mm) relative to L2 (0.00 ± 0.06 mm) between immediately after the application and 2 hours of wear (p = 0.02). A significant reduction in ACAr at 1 hour (−0.65 ± 0.75 mm2) (p = 0.01) and 2 hours of wear (−0.81 ± 1.15 mm2) (p = 0.04), as well as in ACW at 2 hours (−0.11 ± 0.14 mm) (p = 0.02) compared to immediately after application of L1 was found. Conclusion Small changes in TIA and anterior chamber occur during two hours of SL wear, but these changes are of limited clinical relevance in healthy subjects.

The visual outcomes and corneal biomechanical properties after PRK and SMILE in low to moderate myopia.

To compare the corneal biomechanical parameters, visual outcome, and epithelial remodeling after small-incision lenticule extraction (SMILE) and photorefractive keratectomy (PRK) for low to moderate myopia. Prospective, interventional, randomized, comparative study. Eighty eyes of 40 patients undergoing bilateral SMILE or PRK for low to moderate myopia (<-5 D SE) were included. They were divided into two groups based on the planned refractive surgery. Visual acuity, corneal biomechanics using Corvis-ST, epithelial mapping via anterior segment optical coherence tomography, and higher-order aberrations were recorded both preoperatively and postoperatively at 6 months and compared. At 6 months follow-up, the corrected distance visual acuity as well as the postoperative spherical equivalent of both the groups were comparable (P = 0.13 and P = 0.32, respectively). The biomechanical parameters like deformation amplitude ratio (P < 0.01), inverse concave radius (P = 0.006), integrated ratio (P < 0.01), stress-strain index (P < 0.01), Ambrosio's relational thickness (ArTH) (P < 0.01), and corneal biomechanical index-laser vision correction (P = 0.02) were altered more in the SMILE group than in the PRK group, while the biomechanically corrected intraocular pressure (P = 0.16) was comparable. Epithelial remodeling (P = 0.59), higher-order aberrations (P = 0.53), and stromal keratocyte loss (P = 0.16) in both the groups were comparable. Both SMILE and PRK are comparably effective procedures for correction of low to moderate myopia in terms of visual outcomes; however, the corneal biomechanical stability in PRK is superior than that in SMILE.

Effects of corneal epithelial remodeling on corneal asphericity after FS-LASIK and Trans-PRK: A prospective study.

To observe the changes in corneal epithelial thickness after FS-LASIK and Trans-PRK surgery and to investigate the impact of corneal epithelial remodeling on Q-value and HOA. In this prospective cohort study, 50 patients (100 eyes) underwent FS-LASIK and 45 patients (90 eyes) underwent Trans-PRK. Anterior segment OCT was used to measure the corneal epithelial thickness in different corneal zones (central zone: 0-2 mm; paracentral zone: 2-5 mm; and mid-peripheral zone: 5-6 mm) preoperatively and postoperatively at 1 week, 1 month, 3 months, and 6 months. The correlation between ΔCET in the superior, nasal, inferior, and temporal region at 6 months postoperatively and ΔQ and ΔHOA was analyzed. At 6 months postoperatively, the epithelial thickness increased in the central, paracentral, and mid-peripheral zones in FS-LASIK and Trans-PRK. Central epithelial thickness and different regions of the paracentral zone and mid-peripheral exhibited significant thickening (P < 0.001). In the para-central zone and mid-peripheral zone, the ΔCET in different regions after LASIK and Trans-PRK was positively correlated with ΔQ (P < 0.05) and ΔHOA (P < 0.05). After FS-LASIK and Trans-PRK, significant epithelial thickening was observed. Epithelial changes in different regions lead to different Q-values in different regions and have different effects on HOA. This has a certain guiding significance for the design of refractive surgery, and minimizing the increase of Q-value may improve the postoperative visual quality.

Repeatability of Corneal Epithelial Thickness Map Using Anterior Segment Optical Coherence Tomography in Normal and Corneal Disease Patients.

To evaluate the repeatability of corneal epithelial thickness (CET) measurements in normal eyes and eyes diagnosed with corneal disease using the epithelial thickness map (ETM) of anterior segment optical coherence tomography (OCT). In this retrospective study, patients with 3 OCT scans using the ETM mode of Cirrus OCT (Carl Zeiss Meditec AG, Jena, Germany) between October 2021 and January 2024 were reviewed. Two groups of subjects were included: (1) normal subjects with no history of ophthalmic surgery, corneal diseases, and topical antiglaucoma medication uses; and (2) subjects with corneal diseases including dry eye syndrome, recurrent corneal erosion, pterygium, and others. 57 eyes of 57 normal subjects and 106 eyes of 76 patients with corneal disease were included. ETM was analyzed in 25 zones (1 zone within 0-2 mm diameter, 8 zones within 2-5 mm diameter, 8 zones within 5-7 mm diameter, and 8 zones within 7-9 mm diameter). Repeatability was evaluated by calculating intraclass correlation coefficient (ICC), coefficient of variation (CoV), within-subject standard deviation (Sw), and Bland-Altman plot. Among a total of 25 sectors, the normal eyes showed high repeatability (ICC > 0.75, CoV 2.17%-5.29%, and Sw 0.76-1.65 μm) in 23 sectors, and in corneal diseases patients also showed high repeatability (ICC >0.75, CoV 4.17%-9.61%, and Sw 1.29-3.34 μm) in 22 sectors. However, the wide range of 95% limit of agreement (LoA) width of Bland-Altman plot presented in corneal disease group and some peripheral zones in normal eyes indicates some variability of CET measurements. Except for a few peripheral sectors, ETM of Cirrus OCT provides repeatable CET measurements in normal eyes, however in corneal disease group, repeatability was not consistently high. To measure CET accurately, performing multiple measurements is advised especially in patients with corneal disease and patients in whom peripheral CET values.

Influence of scleral thickness on photodynamic therapy outcomes in central serous chorioretinopathy.

To test the prognostic role of anterior scleral substantia propria (ASSP) thickness in predicting the 3-month response after half-dose photodynamic therapy (PDT) in central serous chorioretinopathy (CSCR) and to assess its clinical relevance of ASSP in different CSCR phenotypes. A prospective, exploratory, multi-centre cohort study conducted at IRCCS San Martino Hospital (Genoa, Italy) and Jules-Gonin Eye Hospital (Lausanne, Switzerland). Demographic and clinical data, and optical coherence tomography (OCT) were collected at baseline and 3 months after PDT. Based on OCT images, we categorized CSCR phenotypes and collected clinically relevant imaging metrics. ASSP thickness was obtained from four different measurements using anterior segment (AS) OCT. Multivariable regression models were performed to evaluate the distribution of ASSP thicknesses among different CSCR phenotypes and to test the prognostic role of ASSP thickness in discriminating between PDT responders (complete subretinal fluid reabsorption) and partial responders. The study cohort comprised 109 Caucasian patients (82 males, 75.2%) with a total of 142 eyes: 84 eyes simple (59.1%) versus 58 eyes complex (40.9%) CSCR. A linear normal model confirmed a positive association between complex CSCR and higher ASSP thickness (β = 26.1, 95% CL = 12.1/40.1, p < 0.001), with a low prevalence of ciliochoroidal effusion loculations in AS-OCT (1/142 eyes, 0.7%). ASSP thickening was positively linked to the presence of posterior cystoid retinal degeneration (PCRD; p = 0.002), indicating a potential role in the pathogenesis of severe CSCR phenotypes. In the subgroup of treated patients (61 eyes), 63.9% had a complete response after PDT. In these patients a logistic binary model highlighted a significantly higher risk of PDT non-responsiveness (OR = 9.62, 95% CL = 2.44/37.9, p = 0.001) associated with a 60-unit increase in ASSP thickness levels. By contrast, other anatomical parameters (i.e., body surface area, age, gender, axial length) showed no remarkable prognostic roles. This research highlighted the association of ASSP thickening with complex CSCR phenotype in Caucasian patients and its role in predicting PDT efficacy. These findings enhance our comprehension of the anatomical risk factors in patients affected with CSCR and potentially guide a better understanding of non-responsive cases to PDT treatment.

Late corneal ectasia after penetrating and deep anterior lamellar keratoplasty for keratoconus.

To investigate tomographic features of late corneal ectasia after keratoplasty for keratoconus and compare penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK) in terms of incidence, time of onset and risk factors of corneal ectasia. Sixty eyes with PK and 30 eyes with DALK operated between 1999 and 2021 were analyzed. Final Pentacam scans were evaluated together with vision and previous topographies. Main outcome measures were vision, K values, apparent thinning on graft-host cornea and the difference between opposing quadrants in the thinnest point measurements. Anterior segment optic coherence tomography was performed for further evaluation. Mean follow-up was 127.2mo (24-282mo) in PK, and 64.3mo (24-144mo) in DALK. K max was higher in DALK (60.6 vs 56.7 D, P=0.012). Inferior recipient was thinner (595.9 µm) in PK than DALK (662.2 µm, P=0.021), due to longer follow-up. Overall corneal ectasia rate was 20.0% within 24y. Ectasia rate was the same (6.7%) in DALK 2/30 and in PK 4/60 in 10y and 13.3% in 12y (4/30 and 8/60, respectively). It increased to 23.3% (14/60) in PK over 24y. While ectasia was not seen before 7y in PK, it could be seen in DALK starting from the 5th year. The intervals between keratoplasty and ectasia were 144.5mo in PK and 99mo in DALK. Inferior recipient was significantly thinner in 18 eyes with ectasia (502.7 µm) compared to 76 non-ectasia (649.1 µm, P=0.000). Inferior graft was thinner (561.0 vs 620.4 µm, P=0.006), K max (63.3 vs 56.5 D, P=0.000), and anterior elevation was higher in ectasia (89.1 vs 48.6 µm, P=0.002). Accelerated crosslinking was performed on 5 eyes. Inferior-superior recipient and inferior graft thinning on tomography, with high K max and anterior elevation emerge as the most reliable criteria for the diagnosis of late ectasia. The incidence of corneal ectasia increases with the time.

Cataract surgery with endothelial keratoplasty.

This review aims to provide an updated summary of the combined approach of cataract surgery with endothelial keratoplasty (EK), addressing key considerations, including intraocular lens (IOL) choice and calculation, decision between sequential and triple EK, and modifications in surgical techniques and postoperative management. Advances in imaging techniques (Scheimpflug tomography and anterior segment optical coherence tomography) have improved the ability to detect subclinical corneal edema, aiding in surgical decision-making for EK. Recent studies comparing sequential and triple-EK indicate that both methods yield similar visual outcomes. Though triple-EK offers quicker recovery, it may have higher complication rates. The use of gases like SF6 and C3F8 for anterior chamber tamponade is evolving, with conflicting findings on their efficacy in preventing graft detachment. Furthermore, IOL selection remains crucial, as hyperopic refractive surprises are common, and hydrophilic lenses should be avoided owing to the risk of opacification after EK. The combination of cataract surgery with EK has emerged as an effective treatment for patients with corneal endothelial diseases and cataract. Careful preoperative evaluation, appropriate IOL selection, and advances in surgical techniques contribute to better outcomes, although patient-specific factors must guide the choice between sequential and triple-EK procedures.

The Use of Artificial Intelligence for Estimating Anterior Chamber Depth from Slit-Lamp Images Developed Using Anterior-Segment Optical Coherence Tomography.

Primary angle closure glaucoma (PACG) is a major cause of visual impairment, particularly in Asia. Although effective screening tools are necessary, the current gold standard is complex and time-consuming, requiring extensive expertise. Artificial intelligence has introduced new opportunities for innovation in ophthalmic imaging. Anterior chamber depth (ACD) is a key risk factor for angle closure and has been suggested as a quick screening parameter for PACG. This study aims to develop an AI algorithm to quantitatively predict ACD from anterior segment photographs captured using a portable smartphone slit-lamp microscope. We retrospectively collected 204,639 frames from 1586 eyes, with ACD values obtained by anterior-segment OCT. We developed two models, (Model 1) diagnosable frame extraction and (Model 2) ACD estimation, using SWSL ResNet as the machine learning model. Model 1 achieved an accuracy of 0.994. Model 2 achieved an MAE of 0.093 ± 0.082 mm, an MSE of 0.123 ± 0.170 mm, and a correlation of R = 0.953. Furthermore, our model's estimation of the risk for angle closure showed a sensitivity of 0.943, specificity of 0.902, and an area under the curve (AUC) of 0.923 (95%CI: 0.878-0.968). We successfully developed a high-performance ACD estimation model, laying the groundwork for predicting other quantitative measurements relevant to PACG screening.

Prospective In Vivo Confocal Microscopy of the Central Cornea in Terrien Marginal Degeneration.

To analyze central corneal in vivo confocal microscopy (IVCM) in Terrien marginal degeneration (TMD). An observational prospective case-control study. Ten Finnish patients with TMD from a tertiary referral center were compared with 10 age- and sex-matched healthy volunteers. Seven patients had bilateral TMD. Age, anterior segment optical coherence tomography, extent of thinning in clock hours, grade of microdots, and stage of TMD were analyzed. According to Süveges and Wang classification, the median stage of TMD was 2 (range, 2-3) and 2 (range, 2-6), respectively. Twelve (71%) of 17 eyes with clinical TMD showed corneal thinning at all clock hours. The median age at the time of examination was 70 years (range, 28-81), and the median time from diagnosis 8.8 years (range, 6.0-15.2). By IVCM, the epithelium, subepithelial nerve plexus, and endothelium were intact in all eyes. The anterior stroma showed bilateral hyperreflective dots in the central cornea beneath the subepithelial nerve plexus in all eyes, and larger patches were detected in the posterior stroma anterior to Descemet membrane; both were invisible by anterior segment optical coherence tomography. As compared with controls, the grade of anterior microdots increased faster with age before the age of 65, and that of posterior stromal patches was higher. Two patients additionally had bilateral hyperreflective needle-like deposits in the anterior and midstroma. By IVCM, TMD is characterized regardless of clinical laterality by bilateral microdots in the central corneal stroma. They might be a supporting diagnostic criterion and alone could suggest subclinical disease.

Associations of ocular anterior segment structures with sex and age: the Yamagata study (Funagata).

To investigate the associations of tomographic parameters in anterior segment optical coherence tomography (AS-OCT) with sex and age in a cohort study. A cohort design. AS-OCT data from 391 Japanese participants aged ≥ 35 years were obtained using swept-source OCT. In the cornea, the keratometric power at the flat (Kf) and steep (Ks) meridians, maximum keratometric power (Kmax), keratometric cylinder, spherical power, regular astigmatism, asymmetry, higher-order irregularity (HOI) from the anterior and posterior surfaces, and the central and thinnest corneal thicknesses were evaluated. Also, anterior chamber depth (ACD), lens thickness, crystalline lens rise (CLR), and nasal and temporal angle opening distances at 500μm from the scleral spur (AOD500) were assessed. Sex differences and age-related changes were analyzed. Women exhibited higher anterior Kf, Ks, and Kmax and lower posterior Kf, Ks, and Kmax than men. The ACD and nasal/temporal AOD500 were shorter in women than in men. The CLR was higher in women, whereas the lens thickness did not differ between the sexes, indicating a more anteriorly positioned lens in women. Age-related changes included increased anterior/posterior HOI, increased lens thickness and CLR resulting in decreased ACD and AOD500. This study reveals sex-related differences in corneal shape, anterior chamber conformation, and lens position, as well as age-related changes in tomographic parameters. ACD, CLR, nasal and temporal AOD500 showed significant sex differences in the 50-70s, whereas lens thickness showed no difference.

Role of Anterior Segment Optical Coherence Tomography in Staging and Evaluation of Treatment Response in Infectious Keratitis.

The aim of this study was to evaluate the role of anterior segment optical coherence tomography during follow-up of infectious keratitis and to assess response to treatment. This was a prospective, consecutive, observational clinical series of cases. Twenty-three eyes of 23 patients with clinically proven fungal keratitis were included in the study. The patients received medical treatment according to clinical diagnosis, and follow-up was performed weekly. Slit-lamp examination and photography, and anterior segment optical coherence tomography were performed at initial and follow-up visits until corneal healing occurred. The main outcome measures included infiltrate depth, width, and density; central corneal thickness; minimal corneal thickness; corneal thickness at the site of the lesion; and stromal thickness at the center of the lesion. Twenty-three eyes of 23 patients (17 men and 6 women), mean age 42.5 ± 19 (8-66) years, were clinically diagnosed with fungal keratitis. Localization was central in 14 cases and paracentral/peripheral in 9 cases. Healing time was 6 to 12 weeks. Minimal corneal thickness, corneal thickness at the site of lesion, and stromal thickness at the center of lesion, and also infiltrate width and depth changed significantly from the first visit to the healing stage at the last follow-up (0.009, 0.001, 0.007, 0.001, and <0.001, respectively). In cases of fungal keratitis, anterior segment optical coherence tomography can provide the clinician with a quantitative assessment of a number of corneal parameters that can be used to determine effectiveness of therapy and confirm complete healing of the lesions that cannot be achieved by clinical evaluation.

The many faces of secondary angle closure glaucoma: A practical approach to unveil.

Secondary angle closure glaucoma (SACG) can be quite puzzling and can challenge even an experienced glaucoma surgeon. Unlike primary angle closure glaucoma, SACG can have various ocular and systemic associations. A careful review of the symptoms and past ocular and surgical history cannot be overemphasized. Some of the SACG can be refractory, requiring drainage devices. However, sometimes, all it takes is a prompt laser iridotomy. This can significantly reduce ocular morbidity and, in some situations, even blindness. Gonioscopy, often an underutilized technique, is critical in making the right diagnosis. With the advent of imaging techniques such as anterior segment optical coherence tomography and ultrasound biomicroscopy, one can easily pick up the etiology and treat early. As many cases of SACG present acutely, it is critical that one makes a prompt diagnosis. We present here a video bouquet of illustrated examples of SACG and the steps to identify the cause by using different imaging techniques. Through this video, we aim to make the diagnosis of SACG a simpler, more streamlined, and logical process that will help in the accurate diagnosis and management. This video demonstrates various etiologies of secondary angle closure and methods to identify and treat the same. Secondary angle closure can occur either with or without pupillary block. SACG with pupillary block involves mechanisms such as seclusio pupillae, aphakic/pseudophakic glaucoma, phacomorphic glaucoma, and silicon oil-induced glaucoma. In contrast, there are various other etiologies causing anterior pulling or posterior pushing mechanisms that contribute to non-pupillary block SACG. We discuss all of these, along with the imaging modalities needed to identify the same. https://youtu.be/N0bIw7Uknww.

A 6-Month Follow-Up Comparative Study of Single-Step Transepithelial Photorefractive Keratectomy (Trans-PRK) Using the StreamLight Software with and without Epithelial Thickness Customization.

To compare corneal aberrometry, densitometry, and refractive outcomes of single-step Transepithelial Photorefractive Keratectomy (Trans-PRK) with and without epithelial thickness customization. This was a prospective, interventional, randomized controlled study. Patients undergoing Trans-PRK using the WaveLight EX500 laser with StreamLight software (Alcon Laboratories, Forth Worth, TX, USA) were randomly assigned to control (55µm standard epithelial thickness) or customized (thinnest point of epithelial thickness for each patient) groups. MS-39 (CSO, Italy) anterior segment optical coherence tomography was used to measure the epithelial thickness. Inclusion criteria were spherical equivalent <6 diopters (D), astigmatism <4D, and CDVA 20/25 or better. The assessments were at baseline and 6 months post-op: visual acuity, refraction, aberrometry, and corneal densitometry. 108 eyes were enrolled, [control group (n=56) and customized group (n=52)]. Mean epithelial ablation thickness in the customized group was 54.81±3.56µm (p=0.470 vs control group). Both groups experienced significant postoperative increases in higher-order aberrations (HOA) and spherical aberrations, with no significant intergroup differences. Mean HOA RMS (µm) of the frontal cornea and total cornea increased by 0.27, and 0.29, respectively, in the control group, and 0.26 and 0.28, respectively, in the customized group (p<0.001 for all). Mean change in spherical aberrations in the frontal cornea and total cornea was 0.23µm (p<0.001) and 0.25µm (p<0.001), in the control group, and 0.19µm (p<0.001) and 0.20µm (p<0.001), in the customized group. Mean corneal densitometry in anterior cornea decreased by 0.63GSU (p=0.021) and 1.18GSU (p<0.001) in the control and customized groups. In the posterior cornea, it increased by 1.67GSU (p=0.004) and 0.38GSU (p=0.006). No significant differences in refractive and aberrometry outcomes between control and customized Trans-PRK groups, with corneal densitometry changes not affecting visual acuity.

Substance P- and insulin-like growth factor 1-derived tetrapeptides for neurotrophic keratopathy related to leprosy: a clinical trial

PurposeNeurotrophic keratopathy is part of the leprosy sequelae and causes progressive deterioration of visual acuity. Although leprosy is bacteriologically curable, there is currently no efficient treatment. Eye drops containing tetrapeptides, Phenylalanine-Glycine-Leucine-Methionine-amide (FGLM-NH2) and Serine-Serine-Serine-Arginine (SSSR), derived from substance P and insulin-like growth factor 1 (IGF-1), are clinically efficacious in the treatment of corneal epithelial disorders caused by neurotrophic keratopathy. To further investigate the effect of this treatment on leprosy sequalae, we evaluated the clinical efficacy of FGLM-NH2+SSSR eye drops for treating neurotrophic keratopathy. DesignClinical trial: Interventional, multicenter, exploratory, single-arm, before and after comparison. ParticipantsThe eyes (12) of 11 patients, aged >60 years, were studied from two leprosy sanatoriums in Japan. MethodsPatients with neurotrophic keratopathy in leprosy sanatorium, specifically those with corneal perception of <40 mm, assessed by the Cochet-Bonnet corneal esthesiometer, and persistent corneal epithelial defects (PEDs) and/or corneal stromal thinning were included in this study. Those treated for infection in the acute phase were excluded from the study. Eye drops containing FGLM-NH2 0.05% and SSSR 5x10-6% were administered four times daily for up to 3 months. Fluorescein staining and optical corneal sections were photographed using a slit-lamp microscope at protocol-set intervals. Where possible, anterior segment optical coherence tomography was performed before and after the intervention. Main outcome measuresThe primary outcome measured was improvement in neurotrophic keratopathy. The patient was judged to have improved when one or more of the following criteria were met: 1) healing epithelial defects or 2) increased thickness in the thin area of the cornea. Secondary endpoints were visual acuity, subjective findings, and time to complete healing for a PED. ResultsNeurotrophic keratopathy on epithelial defects or stromal thickness improved in 83.3% of the patients (90% confidence interval 56.2%–97.0%, P<0.00001). The mean value of corrected visual acuity increased -0.16 by logarithm of the minimum angle of resolution. There were no adverse events reported in association with the treatment. ConclusionsWe confirmed that FGLM-NH2+SSSR eye drops are effective for neurotrophic keratopathy without any adverse reaction in leprosy. These results should be disseminated to any parties who could need this information.

Changes in Iridotrabecular Contact and Intraocular Pressure after Phacoemulsification in Primary Angle-Closure Disease Spectrum.

To compare changes in the swept-source (SS) anterior-segment optical coherence tomography (AS-OCT) parameters and intraocular pressure (IOP) control after lens extraction in various spectra of primary angle-closure disease (PACD). A total 92 eyes from 92 patients with PACD who underwent lens extraction were included in the study. All patients underwent IOP measurement preoperatively and at 1 day, 1 week, and 1, 3, and 6 months postoperatively. SS AS-OCT was performed in all subjects preoperatively and 1 month postoperatively. All participants were divided into two groups depending on the presence of glaucomatous optic disc or visual field damage (group A, PAC suspect or PAC; group B, PAC glaucoma). The changes in IOP and anterior chamber angle parameters of SS AS-OCT of each group were compared. Regression analysis was performed to find factors associated with the degree of IOP reduction after lens extraction. Preoperatively, there was no significant difference in IOP between the two groups (16.3 ± 2.5 mmHg vs. 16.9 ± 3.2 mmHg, p = 0.297), but the number of glaucoma medications used was greater in group B (0.6 ± 1.0 vs. 2.0 ± 0.9, p < 0.001). Postoperatively, IOP was not significantly different, but the number of medications used was greater in group B (0.2 ± 0.7 vs. 0.9 ± 0.8, p < 0.001). Anterior chamber angle parameters including angle opening distance and trabecular-iris angle had a greater increase in group B after lens extraction. However, the residual iridotrabecular contact (ITC) index was significantly greater in group B (5.6 ± 7.0 vs 10.7 ± 12.1, p = 0.014). A greater change in the ITC index was related to a greater degree of IOP reduction (β coefficient, 0.429; p < 0.001). Eyes with PAC glaucoma had a greater residual ITC index after lens extraction compared with eyes of other PACD spectrum and required a greater number of glaucoma medications to maintain a similar level of IOP.

Change in Tear Layer Thickness under Scleral Contact Lenses in Keratoconus Patients and Normal Cornea Volunteers

Objective: To quantify rate of post-lens tear thickness change under scleral contact lenses in keratoconus patients and normal cornea volunteers. Materials and Methods: We conducted a prospective observational study where semi-scleral lenses were fitted to 20 eyes (5 subjects, 10 eyes in each group). After insertion, post-lens tear thickness was measured at 0, 30 minutes and every hour up to 6 hours using Anterior Segment OCT. To analyze post-lens tear thickness and its rate of change at each time point, both within and between groups, a linear mixed model was used. Results: The initial mean post-lens tear thickness (µm) was 742 ± 50 and 440 ± 50 in keratoconus and normal cornea group, respectively. The mean rate of change (µm/hr) was highest in the first 30 minutes in both groups (80.8 ± 8.7, 132.2 ± 8.8 in keratoconus and normal cornea group). Following the first four hours in keratoconus and the first hour in normal cornea group, the reduction rate in post-lens tear thickness exhibited no statistically significant difference from the rate of change observed during the 5-6 hour period. The mean percentage of total change over 6 hours after lens insertion was higher in normal cornea compared to keratoconus group (36.6% vs 22.5%). Conclusion: The reduction in post-lens tear thickness follows a nonlinear pattern. The mean rate of change was highest after insertion and remained stable after four hours in keratoconus and one hour in normal cornea group. The percent change over the 6-hour period was greater in normal cornea group.

Preliminary antifibrotic and vasoconstrictor effects of adrenaline in Schlemm's canal and suprachoroidal minimally invasive glaucoma surgery in primary open-angle glaucoma.

To investigate the antifibrotic and vasoconstrictor effects of adrenaline in Schlemm's canal and suprachoroidal minimally invasive glaucoma surgery (MIGS). Human trabecular meshwork (TM) cells were treated with different concentrations of adrenaline (0%, 0.0005%, 0.01%), and we measured the effects on contractility, cell viability and the expression of key cell cycle and fibrosis genes. Adrenaline 0.05% was also injected intracamerally in five primary open-angle glaucoma patients undergoing iStent inject or MINIject surgery combined with phacoemulsification. All patients were assessed for ocular and systemic adverse reactions, including the effects on intraoperative pupil size, preoperative and postoperative visual acuity, intraocular pressure, and anterior segment OCT results. Adrenaline significantly reduced the contractility of TM cells in a dose-dependent manner (87.8%, 80.6%, 7.9% matrix contraction with adrenaline 0%, 0.0005%, 0.01%, respectively). Adrenaline did not exhibit any significant cytotoxicity even at high concentrations (P > 0.05). Adrenaline 0.01% significantly downregulated the expression of key cell cycle genes in the G2 and M phases, and also decreased the expression of MRTFB and ACTA2 genes (P < 0.05). Intracameral injections of adrenaline 0.05% in the five MIGS patients did not result in any ocular or systemic adverse effects. We recommend intracameral injections of adrenaline 0.05% as a cheap and safe drug to be used before MIGS insertion. Adrenaline decreases the risk of bleeding from the trabecular meshwork and also exhibits antifibrotic effects by arresting the cell cycle, thereby increasing the postoperative success rates in MIGS. What is known Fibrosis is the main cause of surgical failure in minimally invasive glaucoma surgery (MIGS). Mitomycin-C and 5-fluorouracil are too toxic to be used inside the eye. What is new Adrenaline reduced the contractility of trabecular meshwork cells and inhibited the expression of key cell cycle genes and fibrosis genes, without significant cytotoxicity. Intracameral injection of adrenaline 0.05% did not result in any ocular or systemic adverse reactions in MIGS patients.

Association between Tomographic Characteristics of Pterygium and Preoperative Anterior and Posterior Topography Measured by Anterior Segment Optical Coherence Tomography.

Background: The utilities of anterior segment optical coherence tomography (AS-OCT) for characterization, differential diagnosis, postoperative monitoring, and evaluation/comparison of surgical techniques in pterygium are described. Through AS-OCT, it is also possible to study the corneal astigmatic effect of pterygium. Our purpose is to study the associations between the anatomical characteristics of pterygium and the corneal topography through AS-OCT. Methods: Fifty eyes with primary pterygium in a tertiary hospital were evaluated before surgery by measuring 10 anatomical variables of pterygium and 13 topographic variables using AS-OCT (Casia 2; Tomey Corp., Nagoya, Japan). Statistical analysis was used to study the association between them. Results: Pterygium classified as flat pattern exhibited lower preoperative values of flat keratometry (K1), real flat keratometry (K1r), average keratometry (AvgK), and real average keratometry (AvgKr) compared to nodular ones. The flat pattern showed greater cylinder (CYL) and real cylinder (CLYr) values. The horizontal corneal invasion proportionally increased CYL and CYLr. Overall, larger anatomical pterygium measurements (limbus thickness (LimbusT), central pterygium thickness (CentreT), head pterygium thickness (HeadT), epithelial thickness at 1 mm (EpitT1mm), stromal thickness at 1 mm (stromT1mm), total thickness at 1 mm (TotalT1mm), total thickness at 2 mm (TotalT2mm), and total thickness at 3 mm (TotalT3mm)) resulted in lower anterior K1, K1r, AvgK, and AvgKr, and posterior K1 and AvgK values. CentreT was greater in astigmatisms against the rule than in oblique ones. Conclusions: This study demonstrates associations between preoperative topography and the NF (nodular or flat) classification of pterygium and its anatomical measurements assessed by AS-OCT.

Anterior Segment Optical Coherence Tomography Angiography: A Review of Applications for the Cornea and Ocular Surface.

Dye-based angiography is the main imaging modality in evaluating the vasculature of the eye. Although most commonly used to assess retinal vasculature, it can also delineate normal and abnormal blood vessels in the anterior segment diseases-but is limited due to its invasive, time-consuming methods. Thus, anterior segment optical coherence tomography angiography (AS-OCTA) is a useful non-invasive modality capable of producing high-resolution images to evaluate the cornea and ocular surface vasculature. AS-OCTA has demonstrated the potential to detect and delineate blood vessels in the anterior segment with quality images comparable to dye-based angiography. AS-OCTA has a diverse range of applications for the cornea and ocular surface, such as objective assessment of corneal neovascularization and response to various treatments; diagnosis and evaluation of ocular surface squamous neoplasia; and evaluation of ocular surface disease including limbal stem cell deficiency and ischemia. Our review aims to summarize the new developments and clinical applications of AS-OCTA for the cornea and ocular surface.