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Purpose: To evaluate and compare the repeatability of corneal densitometry (CD) measurements obtained using both an anterior-segment optical coherence tomography (AS-OCT) device and a Scheimpflug camera system, while also assessing the level of agreement. The study also sought to investigate the correlation of CD with age, gender, and central corneal thickness (CCT) in normal eyes. Methods: CD measurements were obtained using the Casia 2 and the Pentacam AXL Wave. Data were collected on Total Corneal Densitometry and 4 concentric corneal annular areas, these are referred to as zone 1, denoting the central area, through to zone 4, designating the outermost peripheral region. Repeatability was assessed using intra-session test–retest variability, coefficient of variation (CoV), and intraclass correlation coefficient (ICC). The agreement was evaluated using Bland–Altman plots. Correlation analysis was performed between CD, age, gender, and CCT. Results: The study included 96 healthy volunteers. The Casia 2 demonstrated high repeatability with ICC values exceeding 0.9 in all the corneal zones and lower CoV values compared to the Pentacam AXL Wave (ranging from 1.07% to 2.25% for Casia 2 and from 1.91% to 6.89% for Pentacam).95% LoA were within ± 2 standard deviation from the average mean except from zone 1 (± 2.42).However, the measurements showed a consistent bias among all the corneal zones. CD values were positively correlated with age, except for zone 1 with the Pentacam (p = 0.083). Conclusions: The findings suggest that the Casia 2 can be a reliable tool for assessing corneal transparency in healthy individuals, however its measurements are not interchangeable with those provided by the Pentacam. The AS-OCT device may be more sensitive in detecting subtle age-related changes in CD within the central zone. [ABSTRACT FROM AUTHOR]

Background: Mooren's ulcer (MU) is a rare and debilitating form of peripheral ulcerative keratitis (PUK), characterized by a crescent-shaped ulcer with a distinctive overhanging edge at the corneal periphery. If left untreated, MU can lead to severe complications such as corneal perforation and blindness. Despite various treatment approaches, including anti-inflammatory and cytotoxic drugs, as well as surgical interventions, there is no clear evidence of the most effective treatment due to the lack of randomized controlled trials. AS-OCT is a non-invasive imaging technique that provides high-resolution cross-sectional images of the anterior segment, allowing for accurate evaluation of corneal ulcer characteristics, including depth, extent, and disease progression. Methods: We present the case of a 20-year-old male patient with MU managed using a stepladder approach, which included local and systemic corticosteroids, limbal conjunctival resection, and Cyclosporine A 1% eye drops. The patient underwent consecutive AS-OCT examinations and strict follow-up to tailor systemic and topical therapy. Results: Complete healing of the corneal ulcer with resolution of the inflammatory process was achieved. There was no recurrence of the disease at the 7-month follow-up. AS-OCT demonstrated progressive reorganization and thickening of the stromal tissue until the complete recovery of stromal thickness. Conclusions: The AS-OCT imaging modality allowed for the accurate evaluation of corneal ulcer characteristics, facilitating informed decision-making regarding the use of systemic immunosuppression, surgical interventions, and local immunomodulation and providing detailed and precise assessment of disease progression. This approach enabled a tailored and effective treatment strategy for the patient and played a critical role in guiding the therapeutic approach. [ABSTRACT FROM AUTHOR]

This review aimed to evidence the predisposing conditions for Salzmann nodular degeneration (SND), where particular attention was paid to its association with ocular and systemic diseases. SND is a rare disease characterized by bluish-white nodules located in the mid-periphery of the cornea, which are otherwise completely clear. SND has been found in association with different systemic and ocular diseases, and it may have unilateral or bilateral presentation. Initial forms are only diagnosed occasionally as they are asymptomatic, whereas, in advanced disease, the visual acuity might be seriously impaired. Although SND is well described, its exact etiopathology is currently still unknown and is frequently misdiagnosed. It is associated with ocular surface inflammatory conditions and previous corneal surgery, and it has been described in different systemic diseases. Diagnosis is clinically based with slit lamp examinations, and instrumental assessments with corneal topography permit one to observe the alterations of the corneal profile, whereas anterior segment–optical coherence tomography (AS-OCT) is used to investigate the stromal depth of the nodules. Therapy might be conservative with the objective of improving the ocular surface homeostasis and surgical outcomes, where the aim is to restore the corneal regularity and visual acuity. Ophthalmologists should pay particular attention when detecting nodules in patients with ocular and non-ocular inflammatory diseases to guarantee the patient a timely diagnosis and a better therapeutic outcome. Additionally, collaboration between specialists who deal with treating patients suffering from disorders potentially associated with SND is recommended. [ABSTRACT FROM AUTHOR]

Background/Objectives: The main purpose of this study is to determine, by anterior segment optical coherence tomography (AS-OCT), the anatomical characteristics, both preoperatively and postoperatively, that correlate with a higher rate of pterygium recurrence after surgery with exeresis and conjunctival autograft with biological glue. Methods: A total of 50 eyes which were listed for primary pterygium surgery at an ophthalmology tertiary centre were treated with standard pterygium excision and a conjunctival autograft with tissue glue. Ten variables were measured with AS-OCT (Casia 2; Tomey Corp., Nagoya, Japan) during six control visits with all patients. Finally, statistical analysis was performed using SPSS (SPSS stadistics®, IBM®, version 21.0.0.0) for descriptive variables and R-project (The R foundation©, version 3.0.2) for the rest of the analyses, including a descriptive analysis and an inferential analysis studying prognostic factors of recurrence and their predictive capacity. Results: Among the 50 patients who underwent surgery, recurrence was detected in 8 cases (rate 16%; 95% CI: 5.8–26.2%). Most cases (n = 6) were detected 3 months after surgery. The pattern of recurrences was atrophic in two thirds of the cases; none required reintervention. Preoperative total conjunctival thickness at 3 mm was significantly increased in patients who developed recurrence. One week after surgery, epithelial and stromal thickness at 1 mm and total thickness at 3 mm proved to be useful for predicting recurrence. Both models have significant discriminant capacity. Conclusions: By imaging the graft with AS-OCT preoperatively and 7 days after surgery, the risk of future recurrence can be predicted. [ABSTRACT FROM AUTHOR]

To highlight the importance of swept-source anterior segment optical coherence tomography (SS-ASOCT) in the peri-surgical management of cataract in uveitis. To describe a case of fibrinoid syndrome in uveitis treated with recombinant tissue plasminogen activator (rtPA). SS-ASOCT was performed at each follow-up before and after cataract surgery to assess anterior chamber inflammation and assist the clinical management of the patient. A patient with idiopathic autoimmune uveitis was scheduled for cataract surgery. SS-ASOCT allowed to correctly plan the surgery timing. The patient developed a severe fibrinoid syndrome. Postsurgical SS-ASOCT allowed to distinguish between anterior chamber cells and fibrin thus guiding the timing for rtPA intracameral injection. Visual acuity improved from 20/400 the day after the surgery to 20/40. SS-ASOCT allowed a precise assessment of the inflammatory components (cellular vs fibrinoid) after cataract surgery. Intracameral rtPA was safe and effective in the treatment fibrinoid syndrome in uveitis. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of phacoemulsification on intraocular pressure (IOP) and anterior chamber angle (ACA) morphology in primary angle-closure glaucoma (PACG). Setting and Design: A hospital-based, prospective pre- and post-interventional study was carried out in 40 PAC and PACG eyes post patent PI with visually significant cataracts. Methods: All patients underwent phacoemulsification and were evaluated for IOP control, ACA widening, and disease progression for a minimum of 6 months. Failure was defined as an IOP of >21 mmHg necessitating another intervention, including trabeculectomy and/or an increase in the required number of antiglaucoma medications (AGMs) by >1. Results: A highly statistically significant reduction of IOP (P < 0.0001) was seen with an overall reduction of 42.2% over 6 months and a mean reduction of 8.9 ± 3.59 mmHg, with the requirement of AGMs reducing from 39/40 patients preoperatively to 1/38 postoperatively. Success was seen in 95% of cases, with two patients not achieving target IOP and requiring trabeculectomy. Angle widening was documented in all cases by both gonioscopy and AS-OCT, and none of the patients showed any progression in disc damage and visual field changes. Conclusion: Early cataract surgery in ACG not only helps to control IOP and disease progression by widening angles and improving aqueous outflow but also improves visual acuity and reduces the economic burden of AGMs. It also helps in better evaluation of disease progression by both structural and functional analysis, as was documented by the improved and more reliable visual field indices.

The relationship between diabetes mellitus and ocular complications has been extensively studied by many authors. Diabetic keratopathy has already been well characterized and defined as a clinical entity. This review focuses on exploring corneal epithelial changes in diabetic patients, aiming to provide a pragmatic overview of the existing knowledge on this topic. The paper systematically examines alterations in corneal epithelial structure and their impact on diabetic patients. Advanced imaging techniques are also discussed for their role in precise characterization and improved diagnostics. Additionally, the paper explores the mechanisms behind corneal epithelial changes in diabetes, looking at factors such as hyperglycemia, oxidative stress, and Advanced Glycation End-Products. The impact of altered corneal epithelial integrity on barrier function and susceptibility to external issues is considered, addressing potential links to heightened proteolytic enzyme activities and delayed wound healing observed in diabetic individuals. The review also covers the practical implications of corneal epithelial changes, including the association with corneal erosions, persistent epithelial defects, and an increased risk of dry eye syndrome in diabetic patients. [ABSTRACT FROM AUTHOR]

PurposeMethodsResultsConclusionUveitis-Glaucoma-Hyphema (UGH) syndrome results from contact between the intraocular lens (IOL) and the iris or ciliary body, leading to uveal structure erosion and blood-aqueous barrier breakdown. Treatment involves various drugs, with IOL removal often being necessary. Diagnosis relies on clinical signs, but imaging techniques like ultrasound biomicroscopy (UBM) or anterior segment optical coherence tomography (AS-OCT) are crucial. AS-OCT accurately depicts IOL position and potential contact, emerging as a primary alternative to UBM in the diagnosis. Our study aimed to correlate AS-OCT findings with clinically detectable iris atrophy in pseudophakic patients with IOL-iris chafing and UGH syndrome.The study retrospectively analyzed patients diagnosed with UGH syndrome presenting at the Ocular Immunology Unit of Reggio Emilia, Italy, from January 2019 to August 2023. Patients’ data were collected. Ophthalmological exams and imaging were performed. The peephole sign in AS-OCT images was evaluated. Statistical analyses were conducted, with a significance level of p ≤ 0.05.The study reviewed 22 eyes of 22 patients with UGH syndrome. Four eyes were excluded, leaving 18 patients (8 females, 10 males). Common misdiagnoses included idiopathic anterior uveitis (55.5%) and herpetic anterior uveitis (16.7%). All patients had iris transillumination defects, mostly focal (77.8%). AS-OCT revealed IOL chafing in all the eyes, with peephole sign correlation. More peephole signs occurred with IOL in the sulcus (p-value = 0.08).The study recommends AS-OCT for UGH syndrome confirmation and UBM when IOL-iris chafing is not observed on AS-OCT scans. [ABSTRACT FROM AUTHOR]

Purpose: To predict the presence of angle dysgenesis on anterior-segment optical coherence tomography (ADoA) by using deep learning (DL) and to correlate ADoA with mutations in known glaucoma genes. Participants: In total, 800 high-definition anterior-segment optical coherence tomography (AS-OCT) images were included, of which 340 images were used to build the machine learning (ML) model. Images used to build the ML model included 170 scans of primary congenital glaucoma (16 patients), juvenile-onset open-angle glaucoma (62 patients), and adult-onset primary open-angle glaucoma eyes (37 patients); the rest were controls (n = 85). The genetic validation dataset consisted of another 393 images of patients with known mutations that were compared with 320 images of healthy controls. Methods: ADoA was defined as the absence of Schlemm's canal, the presence of hyperreflectivity over the region of the trabecular meshwork, or a hyperreflective membrane. DL was used to classify a given AS-OCT image as either having angle dysgenesis or not. ADoA was then specifically looked for on AS-OCT images of patients with mutations in the known genes for glaucoma. Results: The final prediction, which was a consensus-based outcome from the three optimized DL models, had an accuracy of >95%, a specificity of >97%, and a sensitivity of >96% in detecting ADoA in the internal test dataset. Among the patients with known gene mutations, (MYOC, CYP1B1, FOXC1, and LTBP2) ADoA was observed among all the patients in the majority of the images, compared to only 5% of the healthy controls. Conclusion: ADoA can be objectively identified using models built with DL. [ABSTRACT FROM AUTHOR]

Purpose: To examine the ocular surface disease in primary open-angle glaucoma (POAG) patients already on treatment versus POAG patients without treatment. Methods: A prospective cohort study was conducted on 120 eyes of 60 POAG patients: 60 treatment-naïve eyes (group I) and 60 eyes already on topical anti-glaucoma medications (AGMs) (group II). All patients had filled out the Ocular Surface Disease Index (OSDI) questionnaire and underwent a comprehensive glaucoma workup. Tear break-up time (TBUT) test, Schirmer's test (type I), corneal sensitivity, anterior segment-optical coherence tomography (AS-OCT), and corneal and conjunctival staining were done at day 1, 1 month, 3 months, 6 months, and 12 months follow-up. Results: On presentation, TBUT, Schirmer's test, tear meniscus height (TMH), and tear meniscus depth (TMD) were significantly higher in group I compared to group II. No significant difference was noted in OSDI score, corneal sensitivity, and tear meniscus area (TMA) between the groups on presentation. Both, lissamine green and rose bengal staining, had higher grades in group II compared to group I. Worsening of ocular surface disease was noted in both groups on follow-up. OSDI score, TBUT, Schirmer's test, TMH, and TMD had better values in group I in comparison to group II on follow-up. Conclusion: The study has identified glaucoma patients on AGMs to be more affected by dry eye disease (DED) compared to treatment-naive glaucoma patients. We found statistically significant differences in values of TBUT, Schirmer tests, lissamine and rose bengal staining, and AS-OCT parameters at baseline and 3, 6, and 12 months follow-up. OSDI scores showed significant differences at 6 and 12 months of follow-up. We recommend consideration of evaluation and management of DED/ocular surface disease in glaucoma patients on topical AGMs, particularly multiple drugs and doses. [ABSTRACT FROM AUTHOR]

Keratoconus is a corneal disease which results in progressive thinning and protrusion of the cornea leading to irregular astigmatism. The purpose of this study was to evaluate longitudinal changes in corneal volume (CV) occurring over time in keratoconus eyes. Consecutive patients affected by keratoconus were evaluated by means of anterior segment-optical coherence tomography (AS-OCT) at two different time points: baseline (T0) and after 1 year (T1). Anterior and posterior refractive value; corneal thickness at the thinnest point (TP) and corneal volume (CV) calculated within discs of 3, 5 and 8 mm of diameter; anterior chamber depth (ACD); and anterior chamber volume (ACV) were obtained. Enrolled patients were divided into 3 groups (groups 1, 2, 3) according to the increasing disease severity and into 2 groups (groups A, B) according to the progression or stability of the disease. Overall, 116 eyes of 116 patients (76 males and 40 females, mean age 34.76 ± 13.99 years) were included. For the entire group of keratoconus patients, in comparison with T0, mean TP decreased at T1 from 458.7 ± 52.2 µm to 454.6 ± 51.6 µm (p = 0.0004); in parallel, mean value of CV calculated at 5 mm and 8 mm decreased significantly (from 10.78 ± 0.8 at T0 to 10.75 ± 0.79 at T1 (p = 0.02), and from 32.03 ± 2.01 mm3 at T0 to 31.95 ± 1.98 at T1 (p = 0.02), respectively). Conversely, there were no statistically significant differences in CV at 3 mm from T0 to T1 (p = 0.08), as well as for ACD and ACV. Regarding the course of the disease, patients belonging to group A showed statistically significant differences from T0 to T1 for TP, and for CV at 3 mm, 5 mm and 8 mm (p < 0.0001, p < 0.0001, p < 0.001 and p = 0.0058 respectively). There were no statistically significant differences for ACD (p = 0.6916) and ACV calculated at 3, 5 and 8 mm (p = 0.7709, p = 0.3765, p = 0.2475, respectively) in group A. At the same time, no statistically significant differences for ACD (p = 0.2897) and ACV calculated at 3, 5 and 8 mm (p = 0.9849, p = 0.6420, p = 0.8338, respectively) were found in group B. There were statistically significant positive correlations between changes of TP and CV at 3 mm (r = 0.6324, p < 0.0001), 5 mm (r = 0.7622, p < 0.0001) and 8 mm (r = 0.5987 p < 0.0001). In conclusion, given the strong correlation with TP, CV might be considered an additional AS-OCT parameter to be used in association with conventional parameters when detecting longitudinal changes in keratoconic eyes. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinical outcomes with fibrin glue in comparison with vicryl sutures for limbal conjunctival wound closure in strabismus surgery. Methods: In this prospective interventional study, patients undergoing horizontal muscle strabismus surgery were randomized into two groups: the vicryl suture group and the fibrin glue group. The limbal conjunctival incisions were closed with 8–0 vicryl in the suture group and with fibrin glue in the other group. The outcomes measured were post-operative conjunctival inflammation and wound apposition, patient comfort with the help of a questionnaire, and conjunctival thickness using anterior segment optical coherence tomography (AS-OCT) for both groups at 6 weeks. Results: The study included 64 eyes of 64 patients (32 eyes in each group). The fibrin glue group performed better than the vicryl suture group for most of the symptoms like redness, irritation, watering, and foreign body sensation till 2 weeks post-operatively (P < 0.001), after which both the groups performed similarly. As for clinical signs, no significant difference was noted between the two groups, except for conjunctival hyperemia, which was significantly lesser in the fibrin glue group at 2 weeks post-operatively (P < 0.001). The conjunctival thickness measured at 6 weeks using AS-OCT revealed that the thickness increased significantly in the suture group compared to that in the glue group (P < 0.001 medial site, P = 0.004 lateral site). Conclusion: Because of greater patient comfort and reduced inflammation associated with fibrin glue, it may be considered as a procedure of choice for conjunctival wound closure in strabismus surgery in the absence of the cost constraints. [ABSTRACT FROM AUTHOR]

PurposeEctasia screening in candidates for laser refractive surgery is mandatory during preoperative evaluation. Despite the availability of modern imaging techniques, refractive surgeons often face borderline decisions when patients present with suspicious tomographic findings. This case series presents refractive candidates with suspicious tomographic findings and demonstrates how to interpret them using Scheimpflug imaging and additional anterior segment optical coherence tomography (AS-OCT).SettingDepartment of Ophthalmology, University Hospital, LMU Munich.Case seriesThis case series examines six potential candidates for refractive surgery with a mean age of 29.2 ± 3.9 years, whose corneal assessments using Scheimpflug imaging raised suspicion for ectasia. Each candidate was additionally examined with AS-OCT and reevaluated. The mean manifest subjective spherical equivalent was -3.67 ± 1.8 diopters. The total corneal thickness measured 537 µm ± 30 µm at its thinnest point. None of the candidates had any reported underlying corneal or ophthalmic diseases, and slit lamp examinations revealed no abnormal morphological findings.ConclusionsBoth Scheimpflug imaging and AS-OCT are appropriate tools for screening refractive candidates for ectasia. While topographic and elevation analyses yielded comparable results regarding corneal structure, the epithelial mapping provided by AS-OCT played a critical role in decision-making for cases with borderline tomographic findings. Establishing a global consensus on the use of epithelial mapping in ectasia screening is necessary.

Purpose: To evaluate the clinical outcomes with fibrin glue in comparison with vicryl sutures for limbal conjunctival wound closure in strabismus surgery. Methods: In this prospective interventional study, patients undergoing horizontal muscle strabismus surgery were randomized into two groups: the vicryl suture group and the fibrin glue group. The limbal conjunctival incisions were closed with 8–0 vicryl in the suture group and with fibrin glue in the other group. The outcomes measured were post-operative conjunctival inflammation and wound apposition, patient comfort with the help of a questionnaire, and conjunctival thickness using anterior segment optical coherence tomography (AS-OCT) for both groups at 6 weeks. Results: The study included 64 eyes of 64 patients (32 eyes in each group). The fibrin glue group performed better than the vicryl suture group for most of the symptoms like redness, irritation, watering, and foreign body sensation till 2 weeks post-operatively (P < 0.001), after which both the groups performed similarly. As for clinical signs, no significant difference was noted between the two groups, except for conjunctival hyperemia, which was significantly lesser in the fibrin glue group at 2 weeks post-operatively (P < 0.001). The conjunctival thickness measured at 6 weeks using AS-OCT revealed that the thickness increased significantly in the suture group compared to that in the glue group (P < 0.001 medial site, P = 0.004 lateral site). Conclusion: Because of greater patient comfort and reduced inflammation associated with fibrin glue, it may be considered as a procedure of choice for conjunctival wound closure in strabismus surgery in the absence of the cost constraints.

Purpose: To predict the presence of angle dysgenesis on anterior-segment optical coherence tomography (ADoA) by using deep learning (DL) and to correlate ADoA with mutations in known glaucoma genes. Participants: In total, 800 high-definition anterior-segment optical coherence tomography (AS-OCT) images were included, of which 340 images were used to build the machine learning (ML) model. Images used to build the ML model included 170 scans of primary congenital glaucoma (16 patients), juvenile-onset open-angle glaucoma (62 patients), and adult-onset primary open-angle glaucoma eyes (37 patients); the rest were controls (n = 85). The genetic validation dataset consisted of another 393 images of patients with known mutations that were compared with 320 images of healthy controls. Methods: ADoA was defined as the absence of Schlemm's canal, the presence of hyperreflectivity over the region of the trabecular meshwork, or a hyperreflective membrane. DL was used to classify a given AS-OCT image as either having angle dysgenesis or not. ADoA was then specifically looked for on AS-OCT images of patients with mutations in the known genes for glaucoma. Results: The final prediction, which was a consensus-based outcome from the three optimized DL models, had an accuracy of >95%, a specificity of >97%, and a sensitivity of >96% in detecting ADoA in the internal test dataset. Among the patients with known gene mutations, (MYOC, CYP1B1, FOXC1, and LTBP2) ADoA was observed among all the patients in the majority of the images, compared to only 5% of the healthy controls. Conclusion: ADoA can be objectively identified using models built with DL.

Purpose: To examine the ocular surface disease in primary open-angle glaucoma (POAG) patients already on treatment versus POAG patients without treatment. Methods: A prospective cohort study was conducted on 120 eyes of 60 POAG patients: 60 treatment-naïve eyes (group I) and 60 eyes already on topical anti-glaucoma medications (AGMs) (group II). All patients had filled out the Ocular Surface Disease Index (OSDI) questionnaire and underwent a comprehensive glaucoma workup. Tear break-up time (TBUT) test, Schirmer's test (type I), corneal sensitivity, anterior segment-optical coherence tomography (AS-OCT), and corneal and conjunctival staining were done at day 1, 1 month, 3 months, 6 months, and 12 months follow-up. Results: On presentation, TBUT, Schirmer's test, tear meniscus height (TMH), and tear meniscus depth (TMD) were significantly higher in group I compared to group II. No significant difference was noted in OSDI score, corneal sensitivity, and tear meniscus area (TMA) between the groups on presentation. Both, lissamine green and rose bengal staining, had higher grades in group II compared to group I. Worsening of ocular surface disease was noted in both groups on follow-up. OSDI score, TBUT, Schirmer's test, TMH, and TMD had better values in group I in comparison to group II on follow-up. Conclusion: The study has identified glaucoma patients on AGMs to be more affected by dry eye disease (DED) compared to treatment-naive glaucoma patients. We found statistically significant differences in values of TBUT, Schirmer tests, lissamine and rose bengal staining, and AS-OCT parameters at baseline and 3, 6, and 12 months follow-up. OSDI scores showed significant differences at 6 and 12 months of follow-up. We recommend consideration of evaluation and management of DED/ocular surface disease in glaucoma patients on topical AGMs, particularly multiple drugs and doses.

The cornea is an important refractive structure in the human eye. The corneal segmentation technique provides valuable information for clinical diagnoses, such as corneal thickness. Non-contact anterior segment optical coherence tomography (AS-OCT) is a prevalent ophthalmic imaging technique that can visualize the anterior and posterior surfaces of the cornea. Nonetheless, during the imaging process, saturation artifacts are commonly generated due to the tangent of the corneal surface at that point, which is normal to the incident light source. This stripe-shaped saturation artifact covers the corneal surface, causing blurring of the corneal edge, reducing the accuracy of corneal segmentation. To settle this matter, an inpainting method that introduces structural similarity and frequency loss is proposed to remove the saturation artifact in AS-OCT images. Specifically, the structural similarity loss reconstructs the corneal structure and restores corneal textural details. The frequency loss combines the spatial domain with the frequency domain to ensure the overall consistency of the image in both domains. Furthermore, the performance of the proposed method in corneal segmentation tasks is evaluated, and the results indicate a significant benefit for subsequent clinical analysis. [ABSTRACT FROM AUTHOR]

Purpose: To study the compensatory corneal epithelial changes after femtolaser-assisted intracorneal ring segment (ICRS) implantation in early and moderate cases of keratoconus (KC) using anterior segment optical coherence tomography (AS-OCT).Patients and Methods: A prospective observational non-randomized study of 40 eyes with mild to moderate KC received femtolaser-assisted ICRS implantation. Ferrara ICRS with different arc lengths and thicknesses were used according to the patients' tomographic pattern. Patients had a clear central cornea, keratometry reading < 60 diopters, and corneal thickness > 400 microns. AS-OCT was performed preoperatively and at 1, 3, and 6 months after surgery. Corneal epithelial thickness (CET) was measured over 17 points (2 mm central and 16 points on 2– 5 mm and 5– 7 mm annular zones) over the pupil center. All data were collected and analyzed.Results: Comparing the preoperative and postoperative data, there was a statistically significant increase in the CET postoperatively throughout the 6-month follow-up period in all zones (p< 0.001). The epithelial thickness (ET) was noticed shortly around and central to the ring ridges by the first month (5– 7 mm zone). By the third month, the flattened central cornea (2 mm zone) and the 2– 5 mm zone showed a significant increase in ET up to the 6th month.Conclusion: ICRS implantation in KC results in a thicker and more regular epithelium in the central corneal zone as a secondary response to the corneal stromal changes induced by the implants. [ABSTRACT FROM AUTHOR]

Abstract Background Keratoconus (KC) is easily recognized by its unique topographic pattern, but it can be difficult to distinguish subclinical form of the disease from the normal cornea. Optovue anterior segment optical coherence tomography (AS-OCT) helps diagnose KC. Aim of the work To assess and the level of agreement of Keratometry-readings (K), Central Corneal Thickness (CCT) and Thinnest Corneal Thickness (TCT) measurements obtained by Optovue AS-OCT and Wavelight Oculyzer Pentacam HR in two groups: KC eyes and normal eyes. Patients and methods This is a prospective clinical observational study. The study included 110 eyes divided into two groups. The study group included 62 eyes with topographic evidence of KC. The control group included 48 eyes of normal subjects with no topographic evidence of KC. All of the participants underwent full cycloplegic refraction, spectacle best-corrected distance visual acuity, comprehensive slit-lamp biomicroscopy and fundoscopy. All participants underwent corneal topography by Pentacam HR and AS-OCT. Results There were highly significant differences between the studied groups as regarding BCVA, intraocular pressure and CCT measurements which were found to be lower among KC group compared to the control one. There were highly significant differences between the studied groups regarding TCT measurement detected by Pentacam HR and AS-OCT which was found to be lower among the keratoconus group compared to the control one (470.9, 455.7 versus 541.9 and 518.7 respectively). Conclusion Both Scheimpflug-based imaging and AS-OCT provide comparable readings with a good agreement regarding corneal pachymetry in keratoconus group with accurate identification of KC eyes and healthy ones. However, there was a significant difference in K readings between both devices in Keratoconus and control group.

Purpose: This study evaluated the agreement and reproducibility of ACA measurements obtained using the built-in software of the CASIA2 (Version 3G.1) and the measurements derived from expert clinicians. Methods: Healthy volunteers underwent ophthalmological evaluation and AS-OCT examination. ACA measurements derived from automated and manual SS location were obtained using the CASIA2 automated software and clinician identification, respectively. The intraobserver, interobserver reproducibility, CASIA2–human grader reproducibility and CASIA2 repeatability were assessed using intraclass correlation coefficients (ICCs). Results: The study examined 58 eyes of 30 participants. The CASIA2 software showed excellent repeatability for all ACA parameters (ICC > 0.84). Intraobserver, interobserver, and CASIA2–human grader reproducibility were also excellent (ICC > 0.87). Interobserver agreement was high, except for nasal TISA500, differing between observers 1 and 2 (p < 0.05). The agreement between CASIA2 measurements and human graders was high, except for nasal TISA500, where observer 1 values were smaller (p < 0.05). Conclusion: The CASIA2 built-in software reliably measures ACA parameters in healthy individuals, demonstrating high consistency. Although a small difference was observed in nasal TISA500 measurements, interobserver and CASIA2–human grader reproducibility remained excellent. Automated SS detection has the potential to facilitate evaluation and monitoring of primary angle closure disease. [ABSTRACT FROM AUTHOR]

Brimonidine is a commonly used drug for glaucoma treatment, which has been linked to ocular autoimmune disorders like uveitis and conjunctivitis. Corneal pathology under brimonidine is generally less common. Here, we report a 78 -year-old male patient suffering from immune corneal stromal inflammation with hypotony and resulting hypotonic maculopathy after 6 weeks after introduction of brimonidine treatment. Systemic work-up for system autoimmune and infectious diseases was negative. We discontinued brimonidine and administered topical prednisolone under which inflammatory corneal signs and intraocular pressure normalized. Chorioretinal folds persisted after 9 months. Our case report suggests monitoring patients under brimonidine for sterile corneal infiltration. [ABSTRACT FROM AUTHOR]

Introduction: Progressive, gradual, non-malignant proliferation of fibrovascular tissue, occurring due to repetitive limbal stem-cell irritation & neovascularization, is referred to as pterygium. It is widespread in equatorial regions of the world, with a prevalence of 22% over a well defined ‘pterygium belt’. pterygium excision leaving bare sclera leads to the re occurrence, where as supplementing bare sclera with conjunctival autograft reduces the recurrence up-to 6%. Objective: Assessment of pterygium thickness preoperative ly & post-surgery keratectomy area along with graft thickness after conjunctival limbal autograft transplantation (CLAT) surgery by anterior segment optical coherence tomography (AS- OCT). Method: 50 patients with primary pterygium were distributed age wise in 4 groups of 20-39, 40-59, 60- 79 & 80-99 years. Anterior segment imaging was performed with RT-vue spectral domain AS-OCT. pterygium thickness pre-operatively & keratectomy area along with autograft thickness after CLAT surgery was evaluated for a follow-up period of 3 months. Results: the pre-op pterygium & 3 months postop keratectomy area thickness at apex for (group 1) were 854um & 573um, (group 2) were 855um & 578um, (group 3) were 859um & 574um and (group 4) were 868um & 575um. Similarly at limbus for (group 1) are 1.13um & 720um, for (group 2) are 1.14um & 725um, for (group 3) are 1.19um & 718um, for (group 4) are 1.24um & 714um. Reduction in graft thickness in 3 months follow period for (group 1) was 311um, (group 2) 304um, (group3) 303um & (group 4) 313um respectively. Conclusions: CLAT ascertains to be the ideal treatment modality for pterygium management in terms of decreasing the complications & recurrence rate. Also, AS-OCT is the optimal investigating modality in assessment of pterygium before & after CLAT surgery. [ABSTRACT FROM AUTHOR]

Purpose: To discuss the novel swept-source anterior segment optical coherence tomography (SS-ASOCT)-guided surgical approach in slipped medial rectus muscles. Methods: Prospectively (between February 2020 and July 2022), six patients with a clinical suspicion of slipped medial rectus muscle were recruited. After complete ophthalmic and orthoptic evaluation, the missing medial rectus muscle is screened using Anterior Segment Optical Coherence Tomography (ASOCT). In presence of a traceable muscle, its morphology, depth, and distance from a fixed anatomical landmarks were noted; in its absence, the status of other recti was noted. Intraoperatively, the features were confirmed and the intended intervention was performed. Results: The mean age of six patients was 25.66 ± 9.72 years, two with surgical trauma and four with penetrating trauma (66.66%). In five patients, the ASOCT traced the slipped medial rectus muscle successfully (83.33%); intraoperatively, the same was confirmed (within 1-2 millimeters) with favorable outcomes. ASOCT made a significant contribution in all subjects by reducing the number of interventions and muscle surgeries. Conclusions: In eyes with slipped medial rectus muscle, especially those which are within a finite distance from the angle can be traced using ASOCT. This approach impacts the outcomes in many ways. [ABSTRACT FROM AUTHOR]

Tomas Loureiro,1 Sandra Rodrigues-Barros,1 Ana Rita Carreira,1 Filipe Gouveia-Moraes,1 Pedro Carreira,1 Ana Vide Escada,1 Paul Campos,1 Ines Machado,1 Nuno Campos,1 Renato Ambrosio Jr,2 Timothy J Archer,3 Dan Z Reinstein3 1Ophthalmology Department, Hospital Garcia de Orta, Almada, Portugal; 2Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil; 3London Vision Clinic, London, UKCorrespondence: Tomas Loureiro, Ophthalmology Department, Hospital Garcia de Orta, Avenida Torrado da Silva, Almada, 2805-267, Portugal, Tel +351 913 513 175, Email loureiro.tomas@gmail.comPurpose: To evaluate the changes on epithelial thickness before and after topical treatment in primary Sjögren syndrome-associated dry eye disease (SS-DED).Methods: This was a prospective study that included referred women with SS-DED and healthy age-matched controls. Corneal epithelial thickness was evaluated using high-definition anterior segment optical coherence tomography (Cirrus 5000 HD-OCT) in the baseline first consultation, and four weeks after treatment with preservative free 1mg/1mL sodium hyaluronate. Schirmer test 1 (ST1), tear break-up time (TBUT), tear meniscus height (TMH), SICCA Ocular Surface Score (SICCA OSS) and Ocular Surface Disease Index (OSDI) were evaluated. Statistical significance was defined as p-value < 0.05.Results: The study included 40 eyes, 20 with SS-DED and 20 controls. At baseline, SS-DED patients had lower ST1 (11.1 ± 2.2mm vs 14.1 ± 3.1mm, p< 0.01), faster TBUT (9.1 ± 1.8s vs 13.2 ± 1.1s, p< 0.01) and lower TMH (211.2 ± 68.4 μm vs 217.2 ± 60.1μm; p< 0.01) than the control group, whereas SICCA OSS and OSDI were higher (p< 0.01). The superior epithelium was thinner in SS-DED group (41.1 ± 3.2 μm vs 43.1± 2.3 μm, p< 0.01). After treatment, ST1, TBUT, TMH, SICCA OSS, and OSDI improved (p< 0.01), and superior epithelium thickened (p< 0.01) in the SS-DED group.Conclusion: Treatment with sodium hyaluronate improved ST1, TBUT, TMH, SICCA-OSS, and OSDI score. Superior epithelium tends to be thinner in SS-DED but becomes thicker with treatment. Our results seem to illustrate the morphological changes in the corneal epithelium in DED, which could be further recognized as a clinical biomarker of SS-DED.Keywords: dry eye disease, Sjogren’s syndrome, epithelial thickness, AS-OCT

The relationship between diabetes mellitus and ocular complications has been extensively studied by many authors. Diabetic keratopathy has already been well characterized and defined as a clinical entity. This review focuses on exploring corneal epithelial changes in diabetic patients, aiming to provide a pragmatic overview of the existing knowledge on this topic. The paper systematically examines alterations in corneal epithelial structure and their impact on diabetic patients. Advanced imaging techniques are also discussed for their role in precise characterization and improved diagnostics. Additionally, the paper explores the mechanisms behind corneal epithelial changes in diabetes, looking at factors such as hyperglycemia, oxidative stress, and Advanced Glycation End-Products. The impact of altered corneal epithelial integrity on barrier function and susceptibility to external issues is considered, addressing potential links to heightened proteolytic enzyme activities and delayed wound healing observed in diabetic individuals. The review also covers the practical implications of corneal epithelial changes, including the association with corneal erosions, persistent epithelial defects, and an increased risk of dry eye syndrome in diabetic patients.

Anterior segment optical coherence tomography (AS-OCT) allows the explore not only the anterior chamber but also the front part of the vitreous cavity. Our cross-sectional single-centre study investigated whether AS-OCT can distinguish between vitreous involvement due to vitreoretinal lymphoma (VRL) and vitritis in uveitis. We studied AS-OCT images from 28 patients (11 with biopsy-proven VRL and 17 with differential diagnosis uveitis) using publicly available radiomics software written in MATLAB. Patients were divided into two balanced groups: training and testing. Overall, 3260/3705 (88%) AS-OCT images met our defined quality criteria, making them eligible for analysis. We studied five different sets of grey-level samplings (16, 32, 64, 128, and 256 levels), finding that 128 grey levels performed the best. We selected the five most effective radiomic features ranked by the ability to predict the class (VRL or uveitis). We built a classification model using the xgboost python function; through our model, 87% of eyes were correctly diagnosed as VRL or uveitis, regardless of exam technique or lens status. Areas under the receiver operating characteristic curves (AUC) in the 128 grey-level model were 0.95 [CI 0.94, 0.96] and 0.84 for training and testing datasets, respectively. This preliminary retrospective study highlights how AS-OCT can support ophthalmologists when there is clinical suspicion of VRL. [ABSTRACT FROM AUTHOR]

Background: The aim of this work is to compare slit lamp (SL) examination and anterior segment optical coherence tomography (AS-OCT) for the evaluation of central infectious corneal perforation. Methods: This observational study included 50 eyes of 50 patients with central infectious corneal perforation. Each eye was subjected to both examination modalities, SL and AS-OCT, for the pre-treatment and post-treatment examinations. Results: The progress of healing started from day 7, 5 eyes (10%) appeared to be healed by SL, and only 3 (6%) appeared to be healed by OCT. All eyes appeared to be healed in the 1st month, 39 (78%) of them appeared to be healed by OCT and 45 eyes (90%) appeared to be healed by the 2nd month, the final healed eyes were 46 (92%) at the 3rd month. The first appeared to be healed is the corneal epithelium as seen by both SL and OCT after one month, corneal stroma appeared to be entirely healed in the first month by SL but by OCT, 39 eyes (78%) healed by the first month and the rest 11 (22%) had partial healing by OCT. In the third month, 46 eyes (92%) had complete callous formation as seen by OCT and the rest 4 eyes (8%) had partial or incomplete healing. Conclusions: AS-OCT is a reliable non-invasive tool for the evaluation of corneal perforation and its progression of healing. It was superior and more accurate than SL in the assessment of corneal perforation as it provides information on wound healing and the surrounding tissue in layers that can detect any surprise that can not be seen by the slit lamp. [ABSTRACT FROM AUTHOR]

Childhood uveitis is a sight-threatening condition, because if not properly recognized and treated can lead to several ocular complications and blindness. It represents a real challenge not only from an etiologic/diagnostic point of view, but also for management and therapy In this review we will discuss the main etiologies, the diagnostic approach, risk factors associated to childhood noninfectious uveitis (cNIU), and the difficulties in eye examination in childhood. Moreover, we will discuss the treatment of cNIU in terms of therapeutic choice, timing of initiation, and withdrawal. Identification of specific diagnosis is mandatory to prevent severe complications, thus a thorough differential diagnosis is essential. Pediatric eye examination may be extremely challenging due to the scarce collaboration, but novel techniques and biomarkers will help in identifying low grade of inflammation, eventually modifying long-term outcomes. Once identified the appropriate diagnosis, recognition of children who may benefit of a systemic treatment is crucial. What, When, and how long are the key questions to address in this field. Current evidence and future results of ongoing clinical trials will help in driving treatment. A proper ocular screening, not only in the context of systemic disease, should be discussed by experts. [ABSTRACT FROM AUTHOR]

Background: Keratoconus (KC) is easily recognized by its unique topographic pattern, but it can be difficult to distinguish subclinical form of the disease from the normal cornea. Optovue anterior segment optical coherence tomography (AS-OCT) helps diagnose KC. Aim of the work: To assess and the level of agreement of Keratometry-readings (K), Central Corneal Thickness (CCT) and Thinnest Corneal Thickness (TCT) measurements obtained by Optovue AS-OCT and Wavelight Oculyzer Pentacam HR in two groups: KC eyes and normal eyes. Patients and methods: This is a prospective clinical observational study. The study included 110 eyes divided into two groups. The study group included 62 eyes with topographic evidence of KC. The control group included 48 eyes of normal subjects with no topographic evidence of KC. All of the participants underwent full cycloplegic refraction, spectacle best-corrected distance visual acuity, comprehensive slit-lamp biomicroscopy and fundoscopy. All participants underwent corneal topography by Pentacam HR and AS-OCT. Results: There were highly significant differences between the studied groups as regarding BCVA, intraocular pressure and CCT measurements which were found to be lower among KC group compared to the control one. There were highly significant differences between the studied groups regarding TCT measurement detected by Pentacam HR and AS-OCT which was found to be lower among the keratoconus group compared to the control one (470.9, 455.7 versus 541.9 and 518.7 respectively). Conclusion: Both Scheimpflug-based imaging and AS-OCT provide comparable readings with a good agreement regarding corneal pachymetry in keratoconus group with accurate identification of KC eyes and healthy ones. However, there was a significant difference in K readings between both devices in Keratoconus and control group. [ABSTRACT FROM AUTHOR]

Purpose: To discuss the novel swept-source anterior segment optical coherence tomography (SS-ASOCT)-guided surgical approach in slipped medial rectus muscles. Methods: Prospectively (between February 2020 and July 2022), six patients with a clinical suspicion of slipped medial rectus muscle were recruited. After complete ophthalmic and orthoptic evaluation, the missing medial rectus muscle is screened using Anterior Segment Optical Coherence Tomography (ASOCT). In presence of a traceable muscle, its morphology, depth, and distance from a fixed anatomical landmarks were noted; in its absence, the status of other recti was noted. Intraoperatively, the features were confirmed and the intended intervention was performed. Results: The mean age of six patients was 25.66 ± 9.72 years, two with surgical trauma and four with penetrating trauma (66.66%). In five patients, the ASOCT traced the slipped medial rectus muscle successfully (83.33%); intraoperatively, the same was confirmed (within 1–2 millimeters) with favorable outcomes. ASOCT made a significant contribution in all subjects by reducing the number of interventions and muscle surgeries. Conclusions: In eyes with slipped medial rectus muscle, especially those which are within a finite distance from the angle can be traced using ASOCT. This approach impacts the outcomes in many ways.

Tomás Loureiro,1 Sandra Rodrigues-Barros,1 Ana Rita Carreira,1 Filipe Gouveia-Moraes,1 Pedro Carreira,1 Ana Vide Escada,1 Paul Campos,1 Inês Machado,1 Nuno Campos,1 Timothy J Archer,2 Dan Z Reinstein,2 Renato Ambrósio Jr3 1Ophthalmology Department, Hospital Garcia de Orta, Almada, Portugal; 2London Vision Clinic, London, UK; 3Federal University of the State of Rio de Janeiro, Rio de Janeiro, BrazilCorrespondence: Tomás Loureiro, Ophthalmology Department, Hospital Garcia de Orta, Avenida Torrado da Silva, Almada, 2805-267, Portugal, Tel +35 1 913 513 175, Email loureiro.tomas@gmail.comPurpose: To evaluate the effect of eye rubbing on the epithelial thickness profile in tomographically normal corneas by AS-OCT and to compare right and left eyes in right-handed children.Methods: Thirty right-handed boys (mean age 11.2 years) with ocular allergy and history of eye rubbing were evaluated using Scheimpflug (Pentacam HR, Oculus Wetzlar, Germany) and anterior segment optical coherence tomography. Epithelial thickness (ET) and full corneal thickness (CT) parameters were compared between right and left eyes with a non-parametric Mann–Whitney test. A p-value lower than 0.05 was considered for statistical significance.Results: No eyes had topometric nor tomographic criteria for keratoconus. The min-max ET was lower in right eyes (− 2.8 μm vs − 3.5; p = 0.02). The difference between inferior and superior (I-S) octants was lower in right eyes (1.1 μm vs 1.9 μm; p = 0.03) as a result of inferotemporal thinning. The highest ET difference was registered between nasal and temporal octants and was more pronounced in the right eyes (2 μm vs 3.1 μm; p < 0.001).Conclusion: AS-OCT analyses reveal different epithelial thickness patterns between the eyes in young atopic patients, likely eye rubbers. Inferior and temporal epithelial thickness seem to be more affected by thinning in the eye on the side of the dominant hand.Keywords: eye rubbing, keratoconus, epithelial thickness, AS-OCT, pediatrics

Abstract Purpose: To estimatethe power of an implanted intraocular lens (IOL) by measuring IOL thickness using anterior segment optical coherence tomography (AS-OCT) and to assess the repeatability of measurements. Methods: Ninety-seven eyes were studied one month after uneventful phacoemulsification within the bag Acrysof SA60AT IOL implantation (range +11 to +35). All eyes had postoperative refraction of ± 0.5 D of target refraction. AS-OCT was used to measure the central thickness of the IOL. Correlation between labelled IOL power and central IOL thickness as well as the measure of repeatability, for example, intraclass correlation coefficient (ICC), were evaluated. IOL thicknesses were also calculated using a formula and compared with AS-OCT derived measurements. Results: IOL thickness correlated significantly with labelled IOL power (R2 = 0.985, P < 0.001). The regression equation (IOL Power = [0.04 × IOL thickness in micron] – 7.56) indicates 25 microns of central IOL thickness change per 1D power change. Over the studied range, IOL power could be estimated with a precision of 0.85 ± 0.02 D (95% confidence interval: 0.83–0.94D). ICC for repeated measurements was 0.999. There was a significant correlation between calculated and measured (AS-OCT) IOL thickness (R2 = 0.984, P < 0.001). Conclusion: Central IOL thickness measurements with the AS-OCT are highly repeatable and closely correlated with the labelled IOL power, which can predict the IOL power with ± 0.85 D from the actual power. This method can be helpful in cases of postoperative IOL surprise.

One of the leading global causes of vision impairment due to anterior segment disease is herpes simplex keratitis (HSK). The routine clinical method in the diagnosis of HSK is examination of the eye using slit lamp biomicroscopy; nevertheless, this is a subjective examination and can potentially lead to an erroneous diagnosis. Optical devices such as in vivo confocal microscopy and anterior segment optical coherence tomography are among the additional diagnostic tools that provide a valuable resource in the diagnosis and management of the condition. In research settings, these technologies have already enhanced our understanding of the microscopic causes of numerous common in vivo observations. This review aims to highlight the multiple emerging clinical and research applications for optical imaging devices in HSK. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate anterior segment optical coherence tomography (AS‐OCT) features of Descemet's membrane endothelial keratoplasty (DMEK) grafts associated with graft attachment worsening over time. Methods: Retrospective case series on patients who received uncomplicated DMEK surgery and for whom subsequent AS‐OCT data were available for analysis. Patients' demographics and surgical details were collected. AS‐OCT was analysed for graft detachment axial extension, presence of posterior stromal ripples, quadrant involvement (location and number), degree of detachment extension, peripheral roll, presence and amount of air in the anterior chamber (AC). Features associated with re‐bubbling and graft detachment worsening over time were identified. Results: A total of 147 patients with a mean age of 70.8 ± 9.8 years (63% females) were included. AS‐OCT was performed at 2.9 ± 2.4 days after surgery. AS‐OCT factors associated with re‐bubbling were posterior stromal ripples (p = 0.004) and detachment axial extension (p < 0.001). At first follow‐up, of the 147 DMEK, 67 showed complete attachment and 80 partial detachment. In those cases of initially completely attached grafts, posterior stromal ripples were associated with the risk of subsequent graft detachment (p = 0.014) together with recipient age (p = 0.043), phaco‐combined surgery (p = 0.018) and AS‐OCT timing (p = 0.033); while, in the initially partially detached grafts, detachment worsening was associated with posterior stromal ripples (p = 0.025), detachment axial extension (p = 0.003), degrees of detachment involvement (p = 0.029), peripheral roll‐in shape (p = 0.033) and presence of air in the AC (p = 0.032). Relative risk (RR) of graft detachment worsening in patients with moderate/severe posterior stromal ripples was 1.75 (95% CI = 1.09–2.81). Conclusion: Posterior stromal ripples and detachment axial extension >1/3 of graft surface area were the main risk factors for detachment worsening over time, and patients showing these features should be monitored closely to identify the need for re‐bubbling at an early stage, thus improving surgical outcomes. [ABSTRACT FROM AUTHOR]

Keratoconus is a corneal disease which results in progressive thinning and protrusion of the cornea leading to irregular astigmatism. The purpose of this study was to evaluate longitudinal changes in corneal volume (CV) occurring over time in keratoconus eyes. Consecutive patients affected by keratoconus were evaluated by means of anterior segment-optical coherence tomography (AS-OCT) at two different time points: baseline (T0) and after 1 year (T1). Anterior and posterior refractive value; corneal thickness at the thinnest point (TP) and corneal volume (CV) calculated within discs of 3, 5 and 8 mm of diameter; anterior chamber depth (ACD); and anterior chamber volume (ACV) were obtained. Enrolled patients were divided into 3 groups (groups 1, 2, 3) according to the increasing disease severity and into 2 groups (groups A, B) according to the progression or stability of the disease. Overall, 116 eyes of 116 patients (76 males and 40 females, mean age 34.76 ± 13.99 years) were included. For the entire group of keratoconus patients, in comparison with T0, mean TP decreased at T1 from 458.7 ± 52.2 µm to 454.6 ± 51.6 µm (p = 0.0004); in parallel, mean value of CV calculated at 5 mm and 8 mm decreased significantly (from 10.78 ± 0.8 at T0 to 10.75 ± 0.79 at T1 (p = 0.02), and from 32.03 ± 2.01 mm3 at T0 to 31.95 ± 1.98 at T1 (p = 0.02), respectively). Conversely, there were no statistically significant differences in CV at 3 mm from T0 to T1 (p = 0.08), as well as for ACD and ACV. Regarding the course of the disease, patients belonging to group A showed statistically significant differences from T0 to T1 for TP, and for CV at 3 mm, 5 mm and 8 mm (p < 0.0001, p < 0.0001, p < 0.001 and p = 0.0058 respectively). There were no statistically significant differences for ACD (p = 0.6916) and ACV calculated at 3, 5 and 8 mm (p = 0.7709, p = 0.3765, p = 0.2475, respectively) in group A. At the same time, no statistically significant differences for ACD (p = 0.2897) and ACV calculated at 3, 5 and 8 mm (p = 0.9849, p = 0.6420, p = 0.8338, respectively) were found in group B. There were statistically significant positive correlations between changes of TP and CV at 3 mm (r = 0.6324, p < 0.0001), 5 mm (r = 0.7622, p < 0.0001) and 8 mm (r = 0.5987 p < 0.0001). In conclusion, given the strong correlation with TP, CV might be considered an additional AS-OCT parameter to be used in association with conventional parameters when detecting longitudinal changes in keratoconic eyes.

The cornea is an important refractive structure in the human eye. The corneal segmentation technique provides valuable information for clinical diagnoses, such as corneal thickness. Non-contact anterior segment optical coherence tomography (AS-OCT) is a prevalent ophthalmic imaging technique that can visualize the anterior and posterior surfaces of the cornea. Nonetheless, during the imaging process, saturation artifacts are commonly generated due to the tangent of the corneal surface at that point, which is normal to the incident light source. This stripe-shaped saturation artifact covers the corneal surface, causing blurring of the corneal edge, reducing the accuracy of corneal segmentation. To settle this matter, an inpainting method that introduces structural similarity and frequency loss is proposed to remove the saturation artifact in AS-OCT images. Specifically, the structural similarity loss reconstructs the corneal structure and restores corneal textural details. The frequency loss combines the spatial domain with the frequency domain to ensure the overall consistency of the image in both domains. Furthermore, the performance of the proposed method in corneal segmentation tasks is evaluated, and the results indicate a significant benefit for subsequent clinical analysis.

Abstract Background To report a case of a patient showing bilateral corneal opacities after amantadine chronic treatment for Parkinson’s Disease (PD) and corneal edema associated with intra-epithelial and -endothelial depositions. After amantadine discontinuation a complete clinical remission with only a partial ultrastructural corneal recovery was reported. Case presentation We describe a 78-year-old man with non-medical-responding bilateral corneal edema in treatment with systemic Amantadine for PD. In vivo confocal Microscopy (IVCM) analysis revealed hyperreflective particles at the epithelial level and expanded hyperreflective keratocyte and a disarrangement of stromal lamellae; endothelial cells showed hyperreflective intracellular inclusions in central and in peripheral areas with central polymegatism and pleomorphism. After 1 and 6 months the amantadine discontinuation, the absence of bilateral corneal edema and opacities were noted at the slit lamp examination, associated with the disappearance of epithelial and stromal abnormalities, but the persistence of endothelial hyperreflective deposits with a pleomorphism and polymegatism worsening at the IVCM exam. Conclusion The evaluation of a patient’s cornea 6 months after the discontinuation of systemic amantadine therapy showed a clinical complete remission, with a complete resolution of the bilateral corneal oedema. On the other hand, ultrastructurally, amantadine toxicity is a completely reversible phenomenon at the epithelial level; conversely IVCM showed persistent endothelial degradation.

BackgroundTo derive and validate a novel vault prediction formula to improve the predictability and safety of implantable collamer lens (ICL) implantation.MethodsThirty-five patients (61 eyes) with previous posterior chamber intraocular lens implantation were included. Various parameters, such as horizontal-visible iris diameter (HVID), photopic pupil diameter (PPD), axial length (AL), white-to-white (WTW), anterior chamber width (ACW), angle-to-angle (ATA), crystalline lens rise (CLR), anterior chamber depth (ACD), horizontal sulcus-to-sulcus (HSTS), and ciliary sulcus angle (CSA) were measured. Vault was measured at 3 months after surgery using CASIA2 anterior segment optical coherence tomography. The formula was derived using multiple linear regression analysis and named as WH formula. It was validated in 65 patients (118 eyes) to determine the percentage of the ideal postoperative vault range and to compare the differences between the WH formula and the NK, KS, and STAAR formulas.ResultsFinal ICL size, ATA, CSA, and CLR were included in the prediction formula model (adjusted R2 = 0.67, p