bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of Various Modalities for Intraocular Pressure Measurement in Relation to Keratoconus Severity in 246 Eyes of the Homburg Keratoconus Center
Authors: Knauf Daniela , Seitz Berthold , Schießl Gesine , Zemova Elena , Flockerzi Elias 
Published: February 2023

Purpose:
Intraocular pressure (IOP) measurement may be difficult in keratoconus (KC) due to corneal protrusion and irregular astigmatism. This study aimed to assess which IOP measurement modality is least affected by KC severity.

Methods:
Data from 246 corneas of 246 patients with KC were retrospectively analyzed. KC stages were determined using the Topographic KC (TKC) and ABCD KC classifications derived from Pentacam (Oculus, Germany). IOP was measured using Goldmann applanation tonometry (GAT), Ocular Response Analyzer (ORA, Reichert Instruments, USA), and Corvis ST (CST, Oculus, Germany). Cronbach alpha (CA), analysis of variance with Bonferroni correction, Dunnett T3, and Pearson correlation were performed.

Results:
Using CA, the reliability of measurements using various modalities increased to 0.764 to 0.943 when excluding IOP Goldmann overall and in each KC stage (TKC and ABCD). Analysis of variance revealed significant differences between TKC and ABCD stages for almost all IOP modalities. The Bonferroni post hoc test showed significant differences between the measured IOP in earlier and advanced KC stages, except for the biomechanically CST-corrected IOP (bIOP). Pearson correlation analysis showed a significant correlation between IOP and thinnest corneal thickness (TCT) for all IOP modalities except bIOP.

Conclusions:
CST-based bIOP seems to be best suited for IOP measurement in KC because it did not correlate with TCT in contrast to IOP measurements by ORA or GAT. The measurement results from GAT in patients with KC should be interpreted with care and always in view of corneal thickness. As a thumb rule, we suggest to add at least 2 mm Hg to the measured GAT value.
Bacterial Keratitis: Clinical Features, Causative Organisms, and Outcome During a 13-year Study Period
Authors: Almulhim Abdulmohsen , Alkhalifah Muhannad I. , Kalantan Hatem , Alsarhani Waleed K. 
Published: February 2023

Purpose:
This study aimed to review clinical features, causative organisms, complications, and outcome of bacterial keratitis cases at a tertiary eye hospital.

Methods:
A retrospective study was conducted on clinically diagnosed bacterial keratitis cases from 2007 to 2019. Poor outcome was flagged if any of the following was identified: final visual acuity (VA) worse than 20/200, decrease in VA (1 line or worse compared with presenting VA), corneal perforation, endophthalmitis, failed graft, or cases requiring enucleation or evisceration.

Results:
The study included 263 cases of bacterial keratitis with 169 cases (64.3%) of culture-positive bacterial keratitis. Gram-positive bacteria were found to be the causative organism in 106 cases (62.8%). The most common types were coagulase-negative staphylococci (23.1%) and Pseudomonas (23.1%). Culture-positive bacterial keratitis was associated with the development of anterior chamber reaction (≥1+) on multivariate analysis [adjusted odds ratio (OR): 3.03, confidence interval (CI): 1.23–7.45, P = 0.016]. The complications that occurred in the current cohort included visually significant scar (64.7%), perforation (10.8%), cataract (8.8%), nonhealing epithelial defects (8.0%), corneal neovascularization (4.9%), endophthalmitis (4.6%), and hypotony (1.5%). On multivariate analysis, diabetes mellitus (adjusted OR: 3.51, CI: 1.59–7.76, P = 0.002), poor presenting best-corrected VA (adjusted OR: 3.95, CI 1.96–7.96, P < 0.001), and positive cultures (adjusted OR: 2.36, CI: 1.11–5.00, P = 0.025) were associated with poor outcome.

Conclusions:
Culture-negative keratitis had less severe infection and better outcomes when compared to culture-positive bacterial keratitis. Factors associated with poor outcome included diabetes, poor presenting VA, and positive cultures.
Video Grading of Descemet Membrane Endothelial Keratoplasty Surgery to Identify Surgeon Risk Factors for Graft Detachment and Rebubbling: A Post Hoc Observational Analysis of the Advanced Visualization In Corneal Surgery Evaluation Trial
Authors: Muijzer Marc B. , Delbeke Heleen , Dickman Mor M. , Nuijts Rudy M. M. A. , Jimale Hanad , van Luijk Chantal M. , Imhof Saskia M. , Wisse Robert P. L. 
Published: February 2023

Purpose:
The aim of this study was to explore video-graded intraoperative risk factors for graft detachment (GD) and rebubbling in Descemet membrane endothelial keratoplasty surgery.

Methods:
A post hoc analysis of 65 eyes of 65 pseudophakic subjects with Fuchs endothelial dystrophy that underwent Descemet membrane endothelial keratoplasty surgery as part of the Advanced Visualization In Corneal Surgery Evaluation trial. All surgical recordings were assessed by 2 graders using a structured assessment form. A multinominal regression was performed to estimate the independent effect of video-graded intraoperative factors on the incidence of GD and rebubbling. Secondary outcomes are corrected distance visual acuity and endothelial cell density.

Results:
In total, 33 GDs were recorded, of which 17 required rebubbling. No significant predictors for GD or rebubbling were identified. However, the results revealed 2 clinically relevant patterns. An unfavorable graft configuration (ie, wrinkled, tight scroll, or taco-shaped) and a gas-bubble size smaller than the graft diameter were associated with an increased risk of GD [odds ratio (OR) 2.5 and OR 2.26, respectively] and rebubbling (OR 2.0 and OR 2.60, respectively). Inversely, a larger gas-bubble size was associated with a reduced risk of GD (OR 0.37) and rebubbling (OR 0.36). At 3 and 6 months postoperatively, corrected distance visual acuity was poorer in subjects requiring a rebubbling and endothelial cell density loss was higher in subjects with a partial GD.

Conclusions:
Our analysis revealed that the gas-bubble size and graft shape/geometry seem to be relevant clinical factors for GD and rebubbling, whereas descemetorhexis difficulty, degree of graft manipulation, graft overlap, and surgical iridectomy were not associated with an increased risk.
Effect of Head Trauma–Related Deaths on Corneal Endothelial Cell Loss in Eye Bank Donors
Authors: Oseni Jessinta , Rand Gabriel , Moon Jee Young , Gore Patrick , Edwards Brandon , Livesay Tina , Vizzerra Anthony , Chuck Roy S. 
Published: February 2023

Purpose:
The purpose of this study was to examine the effect of head trauma–related deaths on corneal endothelial cell density (ECD) in eye bank donors.

Methods:
This is a retrospective study of 287 corneas from donors with causes of death secondary to motor vehicle accident with sustained head trauma (n = 50), gunshot wound to the head (n = 138), fall with sustained head trauma (n = 2), and non-head–related traumatic causes of death (n = 97). Donors older than age 50 years were excluded due to concern for undiagnosed Fuchs endothelial dystrophy as a potential confounder for the cause of endothelial cell loss. Donor characteristics, ECD, and focal endothelial cell loss on specular microscopy were compared between the groups. Donors in the head trauma and nonhead trauma groups were matched by age; there were 42 age-matched donors in both groups.

Results:
Age and ECD were negatively correlated (Pearson correlation coefficient = −0.57). Death-to-preservation time was not significantly different between the 2 groups (P value = 0.59). The mean ECD in the head trauma group was 2859 ± 370 cells/mm2 and 3041 ± 464 cells/mm2 in the nonhead trauma group. The head trauma group had a lower ECD (178 ± 70 cells/mm2, P value = 0.013). After matching for age, the difference in ECD between the 2 groups was −94 ± 82 cells/mm2 (P value = 0.26). The adjusted odds of having focal endothelial cell loss was not statistically significant (P value = 0.50) between the groups.

Conclusions:
After statistical adjustments, there were no differences between the head trauma and nonhead trauma groups.
Case–Control Study Examining the Composition of the Gut Microbiome in Individuals With and Without Immune-Mediated Dry Eye
Authors: Goodman Courtney F. , Doan Thuy , Mehra Divy , Betz Jason , Locatelli Elyana , Mangwani-Mordani Simran , Kalahasty Karthik , Hernandez Mireya , Hwang Jodi , Galor Anat 
Published: February 2023

Purpose:
Gut microbiome alterations have been associated with various autoimmune diseases. There are limited data, however, on relationships between gut dysbiosis and immune-related dry eye (DE). Our aim was to compare the gut microbiome composition of individuals with early and late markers of Sjögren syndrome (SS) with controls without DE.

Methods:
We compared 20 individuals with positive early markers [antisalivary protein 1 (SP1), antiparotid secretory protein (PSP), anticarbonic anhydrase 6 (CA6) IgG, IgA, and IgM, n = 19)], or late markers (anti-Ro/SS-A and anti-La/SS-B, n = 1) of SS with no comorbid autoimmune diagnoses and 20 age-matched and sex-matched controls. Collected stool samples underwent deep RNA sequencing. The main outcomes measured included gut microbiome composition and diversity.

Results:
A total of 20 cases [Dry Eye Questionnaire-5 15.2 ± 3.4, Ocular Surface Disease Index 55.1 ± 22.8, and Schirmer 7.1 ± 5.2 mm] were compared with 20 controls (Dry Eye Questionnaire-5 4.8 ± 3.8, Ocular Surface Disease Index 14.2 ± 12.3, and Schirmer 20.4 ± 9.2 mm). No differences were observed in α-diversity (P = 0.97) or overall community structure (P = 0.62). Between groups, 32 species were differentially abundant (P < 0.01). Among cases, 27 were relatively more abundant, including 10 Lactobacillus and 4 Bifidobacterium species. A relative depletion of 5 species was found in cases compared with controls, notably Fusobacterium varium and Prevotella stercorea.

Conclusions:
Differences in gut microbiome composition were found in individuals with mostly early markers of SS compared with controls. However, their clinical significance to DE manifestations remains unclear. Further studies are needed to elucidate the role of gut dysbiosis on immune dysregulation and disease activity in the various forms of immune-mediated DE.
Prospective In Vitro Comparison of Kerasave and Optisol-GS Corneal Storage Solutions
Authors: Tran Khoa D. , Ellison Mark , Straiko Megan M. W. , Giurgola Laura , Gatto Claudio , Galloway Joshua D. , Ragazzi Eugenio , D’Amato Tothova Jana 
Published: February 2023

Purpose:
The aim of this study was to compare the performance of Kerasave and Optisol-GS for hypothermic corneal storage for 14 days.

Methods:
This study was a prospective laboratory investigation. Mate corneas were recovered into Kerasave or Optisol-GS (27 pairs) and stored at 2°C to 8°C for 14 days. Corneas were evaluated by trained eye bank technicians, and study parameters were compared between the initial and final evaluations. Endothelial cell density (ECD), hexagonality (HEX), and coefficient of variation (CV) were evaluated by specular microscopy, and central corneal thickness (CCT) was examined by optical coherence tomography after 1, 3, 7, and 14 days of storage. Corneal transparency was scored using slit lamp examination at days 1 and 14.

Results:
Average ECD, HEX, and CV for the Kerasave (2653 ± 303 cells/mm2, 57 ± 4%, and 36 ± 3%) and Optisol-GS (2623 ± 306 cells/mm2, 57 ± 5%, and 36 ± 4%) groups were not significantly different at day 1. There was also no difference at any other study time points (all P > 0.05). ECD did not significantly change from day 1 to day 14 in either group (P > 0.05), but a statistically significant change in HEX and CV was observed between day 1 and day 14 in both groups (P < 0.01). Average CCT measured at day 1 for corneas stored in Kerasave was 622 ± 49 μm and those stored in Optisol-GS was 580 ± 35 μm (P < 0.01). The difference in CCT measurements was not significantly different at day 14 (Kerasave: 674 ± 46 μm vs. Optisol-GS: 647 ± 58 μm, P > 0.05). Corneal transparency was not significantly different between the 2 groups at day 1 or day 14.

Conclusions:
The corneal quality and clinically relevant parameters including ECD, endothelial morphometry, and corneal transparency were not different in corneas stored in Kerasave or Optisol-GS for 14 days. The initial difference in CCT between the 2 groups decreased at day 14. These results demonstrated that Kerasave corneal storage solution preserves the corneal endothelium similarly to Optisol-GS.
Use of Ethylenediaminetetraacetic Acid in Chronic Calcium-Based Chemical Injury
Authors: Arora Anchal , Sahu Srikant Kumar , Muni Ipsita , Sharma Aakash 
Published: February 2023

Purpose:
This study presents the successful management of a patient with chronic chemical-based injury using ethylenediaminetetraacetic acid (EDTA) chelation.

Methods:
This is a case report of a 59-year-old man who presented to us 2 months after a bilateral, accidental, ocular injury with lime particles at his workplace.

Results:
The patient was initially managed with extensive debridement and amniotic membrane grafting for both eyes. At 4-month follow-up, the left eye appeared to have extensive calcium-based plaques. 0.02N EDTA chelation was performed for his left eye. Postchelation, the visual acuity improved to 20/800. At 1-week follow-up, a repeat EDTA chelation was performed. The corneal clarity improved further, and the patient recovered a visual acuity of 20/200.

Conclusions:
EDTA chelation in the setting of calcium deposition in the chronic phase of chemical injuries can be reasonably effective.
Corneal Plana-Like Phenotype With Peripheral Scleralization Associated With a Pathogenic Variant of PITX2: A Case Report
Authors: Franco Elena , Scanga Hannah L. , Nischal Ken K. 
Published: February 2023

Purpose:
The aim of this study was to report a case of corneal plana-like phenotype with bilateral peripheral scleralization associated with a PITX2 pathogenic variant.

Methods:
Clinical findings were obtained by ophthalmologic examination. Molecular diagnosis was performed by whole-exome sequencing in the patient and his parents.

Results:
A 12-month-old male patient present with bilateral peripheral corneal scleralization, corneal plana-like phenotype, and iris hypoplasia. The genetic analysis revealed a de novo PITX2 pathogenic variant (c.323G>A, p.R108H).

Conclusions:

PITX2 c.323G>A (p.R108H) can be associated with a unique corneal plana-like phenotype with peripheral scleralization, and thus, PITX2 should be targeted in genetic testing of this specific phenotype.
Posterior Segment Air Injection–Assisted Descemet Membrane Endothelial Keratoplasty in Pseudophakic and Vitrectomized Eyes
Authors: Li Shaowei , Miao Yuan , Liang Weiyan , Liu Chang , Li Ling 
Published: February 2023

Purpose:
This study aimed to present a novel technique for Descemet membrane endothelial keratoplasty (DMEK) in pseudophakic and vitrectomized eyes.

Methods:
The sterile air was injected into the posterior eye segment (anterior vitreous cavity) as a barrier to prevent the fluid of the vitreous cavity flowing into the anterior chamber, levitating the iris–lens diaphragm to flatten the anterior chamber during the surgery. This approach assists in the unfolding of the donor endothelial graft, helping to perform DMEK surgery on patients with a posterior intraocular lens (IOL) and vitrectomy.

Results:
Four cases presented with corneal endothelial decompensation (pseudophakic bullous keratopathy) with previous IOL implantation and vitrectomy underwent DMEK with this technique. The Descemet endothelial graft unfolding time after air injection was 68.75 ± 8.96 seconds. No graft displacement occurred during the surgery. The uncorrected and corrected distance visual acuities were improved in 3 of 4 patients. The corneas were transparent, and there was no graft detachment observed postoperatively in all 4 patients.

Conclusions:
The posterior eye segment air injection can reduce the difficulty of unfolding the DMEK graft in patients after IOL implantation and vitrectomy and the potential intraoperative and postoperative complications, allowing for easy performance of DMEK surgery on pseudophakic and vitrectomized eyes for corneal endothelial dysfunction.
Clinical Outcomes of Transscleral-Sutured Intraocular Lens Combined With Descemet Membrane Endothelial Keratoplasty
Authors: Gouvea Larissa , Din Nizar , AlShaker Sara , Gendler Shai , Weill Yishay , Chan Clara C. , Rootman David S. 
Published: February 2023

Purpose:
The aim of the study was to report clinical outcomes of Descemet membrane endothelial keratoplasty (DMEK) combined with transscleral-sutured intraocular lens (IOL) compared with DMEK combined with phacoemulsification and posterior chamber IOL (Phaco-DMEK).

Methods:
A retrospective chart review of all patients who underwent DMEK combined with transscleral-sutured intraocular lens fixation or combined with phacoemulsification for Fuchs endothelial corneal dystrophy from 2016 to 2021 at the Toronto Western Hospital or the Kensington Eye Institute (Toronto, ON, Canada) and had at least 18 months of follow-up was performed. Main outcomes were postoperative distance-corrected visual acuity, rebubbling rate, graft survival rate, and complications.

Results:
Twenty-one cases of DMEK combined with transscleral-sutured IOL (DMEK-TSS-IOL) and 44 cases of Phaco-DMEK were evaluated. Twelve eyes (57.15%) had a foldable acrylic 3-piece IOL (AR40E) and 9 (42.85%) had a single-piece polymethylmethacrylate (PMMA) IOL (CZ70BD). LogMAR distance-corrected visual acuity improved significantly from 1.48 ± 0.62 (SD) to 0.86 ± 0.82 (P = 0.01) 12 months after DMEK-TSS-IOL and from 0.41 ± 0.29 logMAR to 0.11 ± 0.11 logMAR (P < 0.0001) after Phaco-DMEK. No statistically significant differences were observed in donor (P = 0.97) or 1-year postoperative endothelial cell density (P = 0.11) between the groups. Rebubbling was necessary in 33.33% of eyes in DMEK-TSS-IOL compared with 25% of Phaco-DMEK eyes (P = 0.55). Graft survival rate was 76.19% in the DMEK-TSS-IOL group compared with 90.90% in the Phaco-DMEK group (P = 0.13).

Conclusions:
Transscleral-sutured IOL combined with DMEK is an option for the management of endothelial diseases in aphakic eyes or those which require IOL exchange for the experienced surgeon. However, when compared with routine Phaco-DMEK, there are higher complication and lower survival rates at 18 months.
Introducing a Revised Tissue Saving Protocol for Combined Topography-Guided Photorefractive Keratectomy and Cross-Linking in Keratoconic Corneas
Authors: Yousif Mohamed Omar , Elkitkat Rania Serag , Edrees Eman Samir , Alaarag Noha Abdelsadek 
Published: February 2023

Purpose:
The aim of this study was to introduce a revised tissue-saving technique for combined topography-guided photorefractive keratectomy (PRK) and cross-linking for keratoconus (KC) treatment and to evaluate its efficacy, safety, and stability.

Methods:
This retrospective, noncontrolled study was performed at Maadi Eye Subspecialty Center and Eye Care Center, Cairo, Egypt. The technique was performed on virgin keratoconic corneas with 3 different morphological patterns of ectasia. It involves performing topography-guided PRK before epithelial removal, followed by customized phototherapeutic keratectomy (PTK) that is tailored to each cornea after studying the treatment profile on the laser treatment screen. The electronic medical records were explored for preoperative and postoperative data, including subjective refraction and topographic data (using Sirius topographer).

Results:
The study was conducted on 123 eyes of 93 patients with a mean age of 27.98 years ±6.06. The follow-up ranged from 6 to 36 months (mean ± SD of 16.2 months ±10.4). The results showed statistically nonsignificant differences among the 3 ectasia subgroups in treatment spherical equivalent, treatment maximum depth, thickness of removed epithelium, and thinnest residual stromal bed. There were statistically significant differences in almost all values between the preoperative and postoperative data, with significant postoperative patients' improvement (P value <0.001). The subgroups' results were almost the same as the whole cohort's results. The safety and efficacy indices of the performed procedure showed remarkably high values (1.48 ± 0.21 and 0.87 ± 0.40, respectively).

Conclusions:
This revised protocol for KC management maximally preserves stromal tissue with proven efficacy, safety, and stability.
Cornea Classic: Stern, Beuerman, Fox, Gao, Mircheff, and Pflugfelder, “The Pathology of Dry Eye: The Interaction Between the Ocular Surface and Lacrimal Glands” (1998)
Authors: Shtein Roni M. 
Published: February 2023

Abstract:
In one of the most frequently cited articles from Cornea, Stern et al's “The pathology of dry eye: the interaction between the ocular surface and lacrimal glands” (1998) revolutionized our current understanding of the pathophysiology of dry eye disease.
Safety and Efficacy of Contact Lenses in Eyes After Simple Limbal Epithelial Transplantation
Authors: Chaudhary Simmy , Kate Anahita , Chappidi Kiranmayi , Basu Sayan , Shanbhag Swapna S. 
Published: February 2023

Purpose:
The aim of this study was to evaluate the safety and efficacy of contact lenses (CLs) in eyes after simple limbal epithelial transplantation (SLET) for limbal stem cell deficiency (LSCD).

Methods:
This retrospective study included 61 eyes with partial or total LSCD which underwent SLET and were fitted with corneal or scleral rigid gas-permeable CLs. The primary outcome measure was best-corrected visual acuity (BCVA) with CLs.

Results:
The median age at presentation was 22 years. The most common cause of LSCD was chemical injury [47/61 eyes (77%)]. Twenty-seven eyes (44%) were fitted with corneal rigid gas-permeable lenses, while 34 eyes (56%) were prescribed scleral lenses. The median duration of interval between SLET and CL trial was 10 months (interquartile range: 4–17). The median preoperative BCVA was logarithm of minimal angle of resolution (logMAR) 1.8. This improved to logMAR 1 (P < 0.001) after SLET and to logMAR 0.6 (P < 0.001) with CLs. Eyes with chemical injury (logMAR 1 vs. 0.6, P = 0.0001), grade 1 (logMAR 0.8 vs. 0.4, P < 0.0001), and grade 2 (logMAR 0.9 vs. 0.6, P = 0.004) corneal scarring had better improvement in BCVA with CLs. No complications were noted until the last follow-up visit.

Conclusions:
CLs, both corneal and scleral lenses, provide significant visual improvement in eyes after SLET with residual corneal scarring. These can be safely prescribed in such eyes without any adverse effects. This option can be considered before offering keratoplasty in these eyes.