[Correlation of posterior segment lesions with anterior segment biometric parameters and FBN1 genotype in patients with Marfan syndrome].

Objective: To investigate the characteristics of posterior segment lesions in Marfan syndrome (MFS) patients and their relationship with anterior segment biometric parameters and FBN1 genotype. Methods: A cross-sectional study was conducted. A total of 121 MFS patients, 76 males and 45 females, with an average age of (11.72±11.66) years, who visited the Department of Ophthalmology, Eye & ENT Hospital of Fudan University from January 2013 to March 2023 were included. The presence of posterior scleral staphyloma was observed using B-mode ultrasound, and macular lesions were identified and classified using the atrophy-traction-neovascularization system based on ultra-widefield fundus images, color fundus images, and optical coherence tomography scans. Anterior segment biometric parameters, including axial length of the eye, average corneal curvature, corneal astigmatism, horizontal corneal diameter, anterior chamber depth, and lens thickness, were collected, and the direction and extent of lens dislocation were observed. Molecular genetic analysis of FBN1 gene mutations in patients was performed using next-generation sequencing based on a panel of ocular genetic diseases, and the impact of the genotype and anterior segment biometric parameters on the posterior segment manifestations was analyzed. Results: Sixty patients exhibited posterior segment lesions, including retinal detachment (4 cases, 3.31%), macular lesions (47 cases, 38.84%), and posterior scleral staphyloma (54 cases, 44.63%). There was statistically significant difference in axial length of the eye between patients with and without posterior scleral staphyloma [23.09 (22.24, 24.43) and 27.04 (25.44, 28.88) mm], between patients with and without macular lesions [23.16 (22.24, 24.61) and 27.04 (25.74, 28.78) mm], and between patients with and without atrophic macular lesions [23.16 (22.24, 24.61) and 27.04 (25.74, 28.79) mm] (all P<0.001). There was statistically significant difference in anterior chamber depth between patients with and without macular lesions [3.11 (2.75, 3.30) and 3.34 (3.09, 3.60) mm] (P<0.05). There was also statistically significant difference in corneal astigmatism between patients with and without posterior scleral staphyloma [2.15 (1.20, 2.93) and 1.40 (1.00, 2.20) diopters] (P<0.05). The location and region of the FBN1 gene mutation not only showed statistically significant difference from the positive rates of posterior scleral staphyloma and macular lesions (all P<0.05), but also influenced the occurrence of atrophic macular lesions (both P<0.05). Patients with FBN1 mutations located in the transforming growth factor ß regulatory sequence had the highest proportion of posterior scleral staphyloma and macular lesions (both 10/11). Conclusions: Posterior scleral staphyloma and macular lesions have a relatively high incidence in MFS patients and tend to progress to more severe grades. The age, axial length of the eye, anterior chamber depth, corneal astigmatism, and location and region of the FBN1 gene mutation are factors affecting the posterior segment lesions in MFS patients.

Repeatability of Automatic Measurements by an Anterior Segment Swept-Source OCT Biometer in Patients With Keratoconus.

PURPOSE: To evaluate the repeatability of automatic measurements of a new anterior segment optical coherence tomographer (ANTERION; Heidelberg Engineering) and their agreement with an anterior segment optical coherence tomography device combined with Placido disc corneal topography (MS-39; CSO) in patients affected by keratoconus. METHODS: Fifty-four consecutive patients were included. Three measurements were performed with the ANTERION and one with the MS-39. Repeatability was assessed by means of within-subject standard deviation, coefficient of variation (CoV), and intraclass correlation coefficient (ICC). Agreement was investigated with the 95% limits of agreement. The paired t-test and Wilcoxon matched-pairs test were performed to compare the measurements of the different devices. RESULTS: Repeatability of ANTERION measurements was high, with an ICC greater than 0.98 for all parameters. Many parameters revealed a CoV of less than 1% and a CoV within 5% was obtained for astigmatism measurements. The ANTERION measured a significantly higher corneal power and the MS-39 more negative posterior keratometric values. These differences were mirrored by a moderate agreement for mean simulated keratometry and poor agreement for total corneal power and posterior keratometry. CONCLUSIONS: The ANTERION revealed high repeatability of automatic measurements and good agreement with the MS-39 for many parameters in patients affected by keratoconus, but for most parameters the two instruments cannot be considered interchangeable. [J Refract Surg. 2024;40(7):e445-e452.].

Topical Tacrolimus in Anterior Segment Disorders in Ophthalmology: A Review.

The purpose of this study is to emphasize topical tacrolimus's role in treating anterior segment diseases in ophthalmology. The present study analyzed research papers and publications from international databases, including Pubmed, MedLine, Google Scholar, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), and Scopus to highlight the significance and advantages of topical application of tacrolimus and its efficacy in treating allergic eye disorders, immune-mediated diseases, and other ocular surface disorders. Tacrolimus and cyclosporine are the two most commonly used topical immunosuppressants in ophthalmology. Tacrolimus is a selective calcineurin inhibitor administered for the prevention and treatment of allograft rejection in solid organ transplant recipients and has a similar mechanism of action to cyclosporine. Management of immune-mediated inflammatory anterior segment requires intense immunosuppression and studies have shown that tacrolimus is ten to hundred times more effective than cyclosporine. Abbreviations: IL-2 = interleukin-2, FDA = Food and Drug Administration Agency, GvHD = graft versus host disease, (Ig)E = immunoglobulin E, SAC = seasonal conjunctivitis, PAC = perennial allergic conjunctivitis, VKC = vernal keratoconjunctivitis, AKC = allergic keratoconjunctivitis, GPC = giant papillary conjunctivitis, PKC = phyctenular keratoconjunctivitis, DED = dry eye disease, TBUT = tear break up time.

Comparison of axial length and anterior segment parameters of patients with myopia measured using 2 fourier-domain optical coherent biometry devices.

BACKGROUND: This study assessed the agreement of ocular parameters of patients with myopia measured using Colombo intraocular lens (IOL) 2 and IOLMaster 700. METHODS: Eighty patients (male, 22; average age, 29.14 ± 7.36 years) with myopia (159 eyes) were included in this study in May 2023. The participants' axial length (AXL), central corneal thickness (CCT), lens thickness (LT), white-to-white distance (WTW), front flat (K1), steep (K2), mean (Km) corneal keratometry, astigmatism (Astig), J0 vector, and J45 vector were measured using the IOLMaster 700 and Colombo IOL 2. The measurements from both devices were compared using the generalized estimating equation, correlation analysis, and Bland-Altman plots. RESULTS: With the Colombo IOL 2, lower values for K2 and J0 (odds ratio [OR] = 0.587, p = 0.033; OR = 0.779, p < 0.0001, respectively), and larger values for WTW, Astig, and J45 (OR = 1.277, OR = 1.482, OR = 1.1, all p < 0.0001) were obtained. All ocular measurements by both instruments showed positive correlations, with AXL demonstrating the strongest correlation (r = 0.9996, p < 0.0001). The intraclass correlation coefficients for AXL and CCT measured by both instruments was 0.999 and 0.988 (both p < 0.0001), and Bland-Altman plot showed 95% limits of agreement (LoA) of -0.078 to 0.11 mm and - 9.989 to 13.486 µm, respectively. The maximum absolute 95% LoA for LT, WTW, K1, K2, and J0 were relatively high, achieving 0.829 mm, 0.717 mm, 0.983 D, 0.948 D, and 0.632 D, respectively. CONCLUSIONS: In young patients with myopia, CCT and AXL measurements obtained with the Colombo IOL 2 and IOLMaster 700 were comparable. However, WTW, LT, corneal refractive power, and astigmatism values could not be used interchangeably in clinical practice.

In Vivo Confocal Microscopy and Anterior Segment Optical Coherence Tomography Findings of Patients with Iridocorneal Endothelial Syndrome

This case report aims to present the findings of in vivo confocal microscopy (IVCM) and anterior segment optical coherence tomography (AS-OCT) in three patients with iridocorneal endothelial (ICE) syndrome. Three female patients 37, 50, and 57 years of age presented with complaints of unilateral visual impairment and elevated intraocular pressure (IOP). Biomicroscopy revealed unilateral pupil irregularities and anterior synechiae, and gonioscopy demonstrated synechiae in the iridocorneal angle. IOP was within normal limits with medical treatment in two patients, while one patient had an IOP of 44 mmHg despite maximal antiglaucomatous treatment. IVCM revealed large, polymorphic, and hyperreflective cells in the corneal endothelial layer of the affected eyes and normal corneal epithelium, stroma, and endothelium in the fellow eyes. AS-OCT findings were normal in healthy eyes, while the affected eye showed synechiae in the iridocorneal angle and a hyperreflective, thickened endothelial layer. The patient with refractory glaucoma underwent trabeculectomy surgery with 5-fluorouracil. In conclusion, IVCM and AS-OCT allow a detailed examination of endothelial cell abnormalities and iridocorneal membranes in ICE syndrome, which is characterized by unilateral pupil and iris irregularities and anterior synechiae mainly in women.

Evaluation of anterior segment parameters between pregnancy trimesters and postpartum with pentacam scheimflug imaging: a prospective study.

PURPOSE: To evaluate the effect of pregnancy on the anterior chamber, corneal parameter, and intraocular pressure measurements; and compare the results between trimesters, postpartum and non-pregnant healthy age-matched women. METHODS: This prospective study included 41 pregnant women and 53 non-pregnant women. Four measurements were taken from the pregnant women, in each trimester and postpartum third month, and once from the control group. Of the individuals included in the study, anterior chamber depth (ACD), anterior chamber volume (ACV), K1 (flat keratometry), K2 (steep keratometry), Kmean (mean value of K1 and K2), anterior chamber angle (ACA), central corneal thickness (CCT), thinnest corneal thickness (TCT), astigmatism value (AST), corneal volume (CV), biometry, axial length (AL), spherical equivalent (SFEQ), intraocular lens power (ILP), VA (visual acuity) datas were recorded. RESULTS: We observed a statistically significant decrease in K2, CCT, ACD, AL and CV in the postpartum period (p = 0.025, p < 0.001, p = 0.029, p = 0.005, p = 0.004 respectively) and a statistically significant increase in ACV, CCT, and TCT as the gestational week progressed in the pregnant group (p = 0.007, p < 0.001, p = 0.025, respectively). A statistically significant decrease in IOP towards to the third trimester, and an increase in the postpartum period was observed (p < 0.001). We did not observe statistically significant changes in K1, Kmean, AST, ACA, VA, ILP, and SFEQ values. CONCLUSION: It is important to investigate the physiological changes that may occur during pregnancy, distinguish them from pathological changes, and avoid unnecessary treatment. We consider that it's also important to guide the timing of anterior segment surgeries such as cataract and refractive surgery and to prescribe glasses/contact lenses.

Aphakia treatment with sutureless scleral fixation or retropupillary iris-claw intraocular lens implantation: visual acuity, anterior segment and keratometry outcomes.

PURPOSE: Evaluation of anterior segment parameters using the Scheimpflug corneal topography 1 year after surgery in patients who underwent sutureless scleral fixation intraocular lens (SFIOL) implantation using the modified Yamane technique and retropupillary iris-claw intraocular lens (RPIOL) implantation. METHODS: A total of 60 eyes from 57 patients who underwent sutureless SFIOL implantation and 57 eyes from 52 patients who underwent RPIOL implantation were included. Anterior chamber depth (ACD), anterior chamber angle (ACA), anterior chamber volume (ACV), anterior-posterior corneal astigmatism, and keratometric values were assessed using the Scheimpflug corneal topography (Pentacam HR, Germany). RESULTS: There was no statistically significant difference in postoperative UCVA and BCVA between the sutureless SFIOL and the RPIOL group (p = 0.236, p = 0.293, respectively). While there was no statistically significant difference in postoperative IOP between the two groups (p = 0.223), a statistically significant decrease in IOP was observed in both groups (p < 0.001). While there was no statistical difference between the sutureless SFIOL group and the RPIOL group in terms of spherical value (p = 0.441) and spherical equivalence (p = 0.237), there was a statistically significant difference in cylindrical value (p < 0.001). While there was a statistical difference in anterior astigmatism (p < 0.001), there was no statistical difference in posterior astigmatism (p = 0.405). There was no statistical difference in terms of ACV, ACD, and ACA between the sutureless SFIOL and the RPIOL group (p = 0.812, p = 0.770, p = 0.401, respectively). CONCLUSION: In this study, although there was a statistical difference in cylindrical value and anterior corneal astigmatism between the sutureless SFIOL and RPIOL groups, vision was not affected. According to this study, sutureless SFIOL and RPIOL are two successful methods in terms of visual acuity, anterior segment, and keratometry outcomes in aphakic patients after phacoemulsification.

The optimization of the vault-predicting formula based on the anterior segment measurements from artemis insight 100.

To optimize and evaluate the accuracy of the vault-predicting formula generated from a very high-frequency digital ultrasound robotic scanner (Artemis Insight 100). The relationship between the achieved lens vault (LVa) at one month after intraocular collamer lens (ICL) implantation surgery and the predicted vault (LVp) was analyzed by a retrospective study, and an optimized formula was built up. Then, the accuracy of the optimized vault-predicting formula was evaluated in a prospective study by comparing the LVa and the predicted vault from the optimized formula (LVop). The retrospective study included 77 patients (133 eyes) while the prospective study enrolled 90 patients (170 eyes). The difference between LVp and LVa at one month after surgery was statistically significant (P < 0.05), and the linear regression analysis of LVa against LVp yielded a good fit (R2 = 0.68). The optimized vault-predicting formula was LVop (µm) = 1.21 × LVp (µm) + 124.73. In the validation study, the difference between LVop and LVa was not statistically significant (P = 0.10), and a good agreement between LVop and LVa was shown by Bland-Altman analysis. The optimized vault-predicting formula could predict the actual LV after ICL implantation surgery, help to select an appropriate ICL size and reduce the need for re-operation.

[Changes in intraocular pressure and biometric parameters of the anterior segment of the eye after intravitreal injections]. / Izmeneniya urovnya vnutriglaznogo davleniya i biometricheskikh pokazatelei perednego segmenta glaza posle intravitreal'nykh in"ektsii.

PURPOSE: This study compares the changes in the parameters of the anterior chamber of the eye using anterior segment optical coherence tomography (AS-OCT) in patients with a natural and artificial lens after treatment of neovascular age-related macular degeneration (nAMD) by multiple intravitreal injections (IVI) of anti-VEGF drugs. MATERIAL AND METHODS: The patients were divided into 2 groups: group 1 (control) included 30 patients (30 eyes) with a natural lens, group 2 - 30 patients (30 eyes) with an intraocular lens (IOL). AS-OCT was performed using the Revo NX tomograph (Optopol, Poland) to analyze anterior chamber depth (ACD) and the parameters of anterior chamber angle (ACA). Intraocular pressure (IOP) was measured with a contact tonometer ICare Pro. RESULTS: In patients with an IOL, the IOP level 1 minute after intravitreal injection (IVI) of an anti-VEGF drug was statistically lower than in the control group, on average by 17.8% during the first IVI and by 28.7% after 1 year of observation (p<0.001). ACD before treatment was statistically significantly higher in patients with IOL compared to patients of group 1 by an average of 39.3% (p<0.001). ACA from the nasal and temporal sides in the meridian 0°-180° before the start of treatment was statistically significantly wider in phakic patients than in the control group, by an average of 15.9±9.3° (p<0.001) and 16.9±8.2° (p<0.001), respectively. According to AS-OCT, there was no shift of the iris-lens diaphragm in patients with an IOL after multiple IVI of an anti-VEGF drug, in contrast to the control group. CONCLUSIONS: AS-OCT was used to determine for the first time the changes in the parameters of the anterior chamber of the eye in patients with a natural and artificial lens after multiple injections of an anti-VEGF drug in the treatment of nAMD.

Congenital Corneal Staphyloma: A Comprehensive Histopathologic Assessment Including Associated Anterior Segment Abnormalities.

Congenital corneal staphyloma is a rare congenital malformation with guarded visual potential. The cornea is opaque, markedly ectatic, and lined by uveal tissue with a variety of associated anterior segment abnormalities. In this case report, the detailed histopathology of this condition is highlighted with an unusual finding of the malformed lens. [J Pediatr Ophthalmol Strabismus. 2024;61(3):e28-e32.].

Implementation of anterior segment ophthalmic telemedicine.

PURPOSE OF REVIEW: The growing push to integrate telemedicine into ophthalmic practices requires physicians to have a thorough understanding of ophthalmic telemedicine's applications, limitations, and recent advances in order to provide well tolerated and appropriate clinical care. This review aims to provide an overview of recent advancements in the use of ophthalmic telemedicine for anterior segment eye examinations. RECENT FINDINGS: Virtual care for anterior segment evaluation relies on appropriate technology, novel workflows, and appropriate clinical case selection. Recent advances, particularly in the wake of the COVID-19 pandemic, have highlighted the utility of home-based assessments for visual acuity, external evaluation, tonometry, and refraction. Additionally, innovative workflows incorporating office-based testing into virtual care, termed 'hybrid telemedicine', enable high-quality ophthalmic testing to inform clinical decision-making. SUMMARY: Novel digital tools and workflows enable high-quality anterior segment evaluation and management for select ophthalmic concerns. This review highlights the clinical tools and workflows necessary to enable anterior segment telehealth.

Nontraditional approaches to sedation for anterior segment surgery: a narrative review.

PURPOSE OF REVIEW: Surgical and anesthetic technological advancement have made both cataract and noncataract anterior segment surgery significantly less invasive and time-intensive, facilitating the transition of some of these procedures from the operating room under monitored anesthesia care (MAC) to the office-based setting without MAC. This transition has been aided by the popularization of nonintravenous approaches to achieving patient sedation for these procedures. In this review, we discuss the literature surrounding traditional and nontraditional methods of achieving patient sedation for anterior segment surgery. RECENT FINDINGS: Our survey of the literature suggests that nonintravenous (IV) approaches to sedation for these procedures may be just as safe, effective, and satisfactory to patients as traditional IV approaches. SUMMARY: As anterior segment surgery becomes less invasive and less time-intensive, providers considering transitioning their cataract and anterior segment surgery out of the operating room and into the office-based setting without MAC anesthesia should consider the non-IV sedation options outlined in this review to achieve adequate patient sedation and comfort.

Anterior segment swept-source optical coherence tomography and ultrasound biomicroscopy in iris and ciliary body lesions.

OBJECTIVES: Differentiation of iris and ciliary body lesions as benign or malignant and cystic or solid is important. The aim of this study was to compare anterior segment swept-source optical coherence tomography (AS SS-OCT) and ultrasound biomicroscopy (UBM) findings in iris and ciliary body tumors. RESEARCH DESIGN AND METHODS: Forty-two eyes of 38 cases with iris and ciliary body tumors imaged with UBM and AS SS-OCT between September 2018 and September 2023 were evaluated retrospectively. RESULTS: Of 42 eyes, 14 had melanoma, 14 iris pigment epithelial (IPE) cysts, 7 nevi, 3 Lisch nodules, 2 iris stromal cysts, 1 pars plana cysts, and 1 iris mammillations. An equivalent (100%) visualization of the anterior tumor margin was obtained with both techniques. Compared to AS SS-OCT, UBM was superior for posterior margin visualization in melanocytic tumors and IPE cysts. Bland-Altman plots demonstrated good agreement between UBM and AS SS-OCT for melanocytic tumors < 2.5 mm in base diameter and < 2 mm in thickness. CONCLUSIONS: Although, UBM is the gold standard for ciliary body and iridociliary tumors. AS SS-OCT should be considered as an excellent alternative to UBM, especially in minimally elevated iris lesions.

TGFß Signaling Dysregulation May Contribute to COL4A1-Related Glaucomatous Optic Nerve Damage.

Purpose: Mutations in the genes encoding type IV collagen alpha 1 (COL4A1) and alpha 2 (COL4A2) cause a multisystem disorder that includes ocular anterior segment dysgenesis (ASD) and glaucoma. We previously showed that transforming growth factor beta (TGFß) signaling was elevated in developing anterior segments from Col4a1 mutant mice and that reducing TGFß signaling ameliorated ASD, supporting a role for the TGFß pathway in disease pathogenesis. Here, we tested whether altered TGFß signaling also contributes to glaucoma-related phenotypes in Col4a1 mutant mice. Methods: To test the role of TGFß signaling in glaucoma-relevant phenotypes, we genetically reduced TGFß signaling using mice with mutated Tgfbr2, which encodes the common receptor for all TGFß ligands in Col4a1+/G1344D mice. We performed slit-lamp biomicroscopy and optical coherence tomography for qualitative and quantitative analyses of anterior and posterior ocular segments, histological analyses of ocular tissues and optic nerves, and intraocular pressure assessments using rebound tonometry. Results: Col4a1+/G1344D mice showed defects of the ocular drainage structures, including iridocorneal adhesions, and phenotypes consistent with glaucomatous neurodegeneration, including thinning of the nerve fiber layer, retinal ganglion cell loss, optic nerve head excavation, and optic nerve degeneration. We found that reducing TGFß receptor 2 (TGFBR2) was protective for ASD, ameliorated ocular drainage structure defects, and protected against glaucomatous neurodegeneration in Col4a1+/G1344D mice. Conclusions: Our results suggest that elevated TGFß signaling contributes to glaucomatous neurodegeneration in Col4a1 mutant mice.

Morphological Features Among Gaussian, Sagittal, and Tangential Curvature Maps in Normal and Keratoconus Eyes Using Anterior Segment Optical Coherence Tomography.

PURPOSE: To investigate and compare the morphological features and differences among Gaussian, Sagittal, and Tangential anterior corneal curvature maps obtained with an anterior segment optical coherence tomographer combined with a Placido disc MS-39 device in keratoconus (KC) and normal eyes. METHODS: Prospective, cross-sectional study including 37 KC and 51 healthy eyes. The pattern of astigmatism and maximum keratometry (Kmax), keratometry at the thinnest point (Ktp) and 2 mm diameter (K 2mm ), and inferior-superior dioptric asymmetry values were obtained and calculated from Gaussian, Tangential, and Sagittal curvature maps using the MS-39 (CSO). RESULTS: In KC eyes, an asymmetric bowtie pattern was observed in 64.86% (24/37), 64.86% (24/37), and 0% in the Sagittal, Tangential, and Gaussian maps, respectively. In normal eyes, 51.0% (26/51), 51.0% (26/51), and 0% showed a symmetric bowtie pattern in the Sagittal, Tangential, and Gaussian maps, respectively. There was a significant difference for the variables Kmax, Ktp, and K 2mm inferior among the Gaussian, Tangential, and Sagittal maps in both normal and KC groups. Sensitivity discriminating between normal and KC eyes was 100%, 97.3%, and 90.9% and specificity was 94.1%, 100%, and 100% for Kmax coming from the Tangential, Gaussian, and Sagittal maps, respectively. CONCLUSIONS: Gaussian maps displayed significantly different morphological features when compared with Sagittal and Tangential maps in normal and KC eyes. Anterior curvature maps from Gaussian maps do not show the morphological pattern of symmetric bowtie in normal eyes nor asymmetric bowtie in KC eyes. Kmax from Gaussian maps are more specific, however less sensitive than Tangential maps in discriminating KC from normal eyes.

A Deep Learning Model for Automatically Quantifying the Anterior Segment in Ultrasound Biomicroscopy Images of Implantable Collamer Lens Candidates.

OBJECTIVE: This study aimed to develop and evaluate a deep learning-based model that could automatically measure anterior segment (AS) parameters on preoperative ultrasound biomicroscopy (UBM) images of implantable Collamer lens (ICL) surgery candidates. METHODS: A total of 1164 panoramic UBM images were preoperatively obtained from 321 patients who received ICL surgery in the Eye Center of Renmin Hospital of Wuhan University (Wuhan, China) to develop an imaging database. First, the UNet++ network was utilized to segment AS tissues automatically, such as corneal lens and iris. In addition, image processing techniques and geometric localization algorithms were developed to automatically identify the anatomical landmarks (ALs) of pupil diameter (PD), anterior chamber depth (ACD), angle-to-angle distance (ATA), and sulcus-to-sulcus distance (STS). Based on the results of the latter two processes, PD, ACD, ATA, and STS can be measured. Meanwhile, an external dataset of 294 images from Huangshi Aier Eye Hospital was employed to further assess the model's performance in other center. Lastly, a subset of 100 random images from the external test set was chosen to compare the performance of the model with senior experts. RESULTS: Whether in the internal test dataset or external test dataset, using manual labeling as the reference standard, the models achieved a mean Dice coefficient exceeding 0.880. Additionally, the intra-class correlation coefficients (ICCs) of ALs' coordinates were all greater than 0.947, and the percentage of Euclidean distance distribution of ALs within 250 µm was over 95.24%.While the ICCs for PD, ACD, ATA, and STS were greater than 0.957, furthermore, the average relative error (ARE) of PD, ACD, ATA, and STS were below 2.41%. In terms of human versus machine performance, the ICCs between the measurements performed by the model and those by senior experts were all greater than 0.931. CONCLUSION: A deep learning-based model could measure AS parameters using UBM images of ICL candidates, and exhibited a performance similar to that of a senior ophthalmologist.

[Current capabilities of anterior segment optical coherence tomography]. / Sovremennye vozmozhnosti opticheskoi kogerentnoi tomografii perednego segmenta glaza.

Optical coherence tomography of the anterior segment of the eye (AS-OCT) is a non-invasive method based on the principles of optical reflectometry (measurement of the degree of backscattering of light passing through transparent or translucent media). Limitations of the first devices of this type were associated with insufficient image quality of the details of the anterior chamber angle and the posterior parts of the lens, primarily due to the "working" level of the scanning wavelength (within 800 µm). Fundamentally new possibilities in the structural and functional assessment of the anterior segment of the eye are associated with the introduction into clinical practice of swept-source AS-OCT device - the CASIA2 anterior optical coherence tomograph (Tomey Corporation, Japan). Its high scanning speed (50 000 A-scans per second) with a wavelength of 1310 µm allows high-quality visualization by building a scan at a depth of 13 mm. The previous model (CASIA SS-1000, Tomey Corporation, Japan) supported scan depth of only 6 mm. This review summarizes the results of research on the clinical use of CASIA2 tomograph.

Repeatability assessment of anterior segment measurements in myopic patients using an anterior segment OCT with placido corneal topography and agreement with a swept-source OCT.

BACKGROUND: The precision of anterior segment biometric measurements in eyes has become increasingly important in refractive surgery. The purpose of this study is to assess the repeatability of the automatic measurements provided by a new spectral-domain optical coherence tomograph (SD-OCT)/Placido topographer (MS-39, CSO) and its agreement with a swept-source OCT (SS-OCT) biometer (CASIA SS-1000, Tomey) in patients with myopia. METHODS: The right eye of 235 subjects was scanned 3 times with both devices. The evaluated parameters included central corneal radius of the steep meridian, central corneal radius of the flat meridian, mean central corneal radius, thinnest corneal thickness, central corneal thickness, anterior chamber depth, corneal volume and diameter. The intraobserver repeatability of the MS-39 measurements was calculated using intraclass correlation coefficient (ICC), within subject standard deviation, coefficient of repeatability, coefficient of variation and repeated-measures analysis of variance of the 3 repeated measurements. The agreement between the two devices was evaluated by 95% limits of agreement (LoA). RESULTS: The majority of the parameters acquired from MS-39 showed high repeatability. The repeatability of corneal diameter was slightly lower than the other measurements, although the ICC remained high. Agreement with the CASIA SS-1000 was good, indicated by the Bland-Altman plots with narrow 95% LoA values for all parameters assessed. CONCLUSIONS: The high repeatability of automatic measurements by the new device supports its clinical application in eyes with myopia, and the good agreement between the two devices indicates they could be used interchangeably for the parameters evaluated.

In Vivo Assessment of Retinal Phenotypes in Axenfeld-Rieger Syndrome.

Purpose: Axenfeld-Rieger syndrome (ARS) is characterized by ocular anomalies including posterior embryotoxon, iridocorneal adhesions, corectopia/iris hypoplasia, and developmental glaucoma. Although anterior segment defects and glaucoma contribute to decreased visual acuity, the role of potential posterior segment abnormalities has not been explored. We used high-resolution retinal imaging to test the hypothesis that individuals with ARS have posterior segment pathology. Methods: Three individuals with FOXC1-ARS and 10 with PITX2-ARS completed slit-lamp and fundus photography, optical coherence tomography (OCT), OCT angiography, and adaptive optics scanning light ophthalmoscopy (AOSLO). Quantitative metrics were compared to previously published values for individuals with normal vision. Results: All individuals demonstrated typical anterior segment phenotypes. Average ganglion cell and inner plexiform layer thickness was lower in PITX2-ARS, consistent with the glaucoma history in this group. A novel phenotype of foveal hypoplasia was noted in 40% of individuals with PITX2-ARS (but none with FOXC1-ARS). Moreover, the depth and volume of the foveal pit were significantly lower in PITX2-ARS compared to normal controls, even excluding individuals with foveal hypoplasia. Analysis of known foveal hypoplasia genes failed to identify an alternative explanation. Foveal cone density was decreased in one individual with foveal hypoplasia and normal in six without foveal hypoplasia. Two individuals (one from each group) demonstrated non-foveal retinal irregularities with regions of photoreceptor anomalies on OCT and AOSLO. Conclusions: These findings implicate PITX2 in the development of the posterior segment, particularly the fovea, in humans. The identified posterior segment phenotypes may contribute to visual acuity deficits in individuals with PITX2-ARS.