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.].

Assessment of the Role and Timing of Glaucoma Surgery in Boston Keratoprosthesis Type 1 Patients.

PURPOSE: To determine the role and optimal timing of glaucoma surgery in relation to Boston keratoprosthesis type 1 (KPro) implantation. DESIGN: Retrospective, comparative, nonrandomized clinical study. METHODS: Single-center study of a total of 100 eyes (100 patients) implanted with a KPro between 2008 and 2017, and diagnosed with glaucoma before or after KPro. Patients were separated into 2 groups: those with preexisting glaucoma and those who developed de novo glaucoma after KPro. Groups were then divided based on whether patients were medically or surgically managed. Glaucoma surgery included glaucoma drainage device (GDD) implantation, trabeculectomy, and cyclophotocoagulation (CPC). Primary outcomes included best-corrected visual acuity (BCVA), glaucoma progression, and complications. Differences in outcomes were compared using parametric and nonparametric tests, as well as log-rank test to compare time-to-outcome events. RESULTS: Among 72 eyes with preexisting glaucoma, 27 (38%) had glaucoma surgery before KPro (18 GDD), whereas 45 (62%) were medically managed only. Among the latter, 19 (42%) needed glaucoma surgery post-KPro (16 GDD). Among 28 eyes with de novo glaucoma, 12 (43%) had glaucoma surgery post-KPro (9 GDD). For eyes with preexisting glaucoma, glaucoma progression was greater with glaucoma surgery performed post-KPro (100%) compared with pre-KPro (74%, P = .016) and to medical management (54%, P = .002). No increase in complications were observed with glaucoma surgery compared to medications only (P > .05), whereas fewer eyes maintained a BCVA of 20/200 or better over time with medical management (P = .013). Eyes with de novo glaucoma had similar progression, BCVA, and complications between medical and surgical care (P > .05). CONCLUSIONS: Glaucoma surgery should be performed before or at the same time as KPro implantation in eyes with preexisting glaucoma. Complication rates are not increased when glaucoma surgery is performed in KPro eyes with either preexisting or de novo glaucoma. To ensure optimal glaucoma control, glaucoma surgery should be performed as early as possible in KPro eyes with good visual potential.

Ophthalmic Assessment in Patients With Darier Disease.

PURPOSE: To assess the prevalence of ophthalmic findings in patients with Darier disease, an autosomal dominant genetic skin disorder, in an effort to evaluate the need for eye examinations in the management of the disease. DESIGN: Prospective observational case series. METHODS: Thirty-six individuals with Darier disease were evaluated by both ocular assessment questionnaire and a comprehensive ophthalmic examination (visual acuity, refraction, external examination, and slit-lamp examination) with emphasis on the eyelids, conjunctiva, and cornea. In addition, questionnaire-based medical interview and skin examination were conducted. RESULTS: According to the medical questionnaire, 39% of patients reported eye problems, 36% dry eye, and 42% eye fatigue after prolonged reading. Ocular examination revealed Darier disease lesions on the eyelids in 55% of the patients, blepharitis in 44%, conjunctival hyperemia in 28%, and short tear film break-up time in 83%. There was no significant relationship between any of these ophthalmic findings and systemic retinoid therapy, sex, or age. CONCLUSIONS: The high prevalence of blepharitis and dry eye highlights the importance of ophthalmologic evaluation of patients with Darier disease.

Ocular surface assessment in times of sanitary crisis: What lessons and solutions for the present and the future?

PURPOSE: To describe the immediate consequences of SARS-CoV-2 and the COVID-19 pandemic on the ocular surface and eye-care professionals, and to discuss the need for a mandatory switch from currently performed tele-screening to true teleconsultation for remote ocular surface assessment. MAIN FINDINGS: Ophthalmologists have been largely impacted by the COVID-19 sanitary crisis, due to both the ocular manifestations of SARS-CoV-2 and to the high contagiousness of the virus. The proximity of ophthalmologists to their patients have pushed eye-care providers to readapt their practices and develop alternatives to face-to-face consultations. However, teleconsultation has some major limitations and drawbacks, especially for ocular surface assessment that relies on high-quality graphic data for adequate diagnosis. Tele-screening, on the other hand, emphasizes on the importance of history-taking and listening to the patient in order to adequately prioritize appointments based on the presumed degree of emergency. CONCLUSION: Despite all the enthusiasm, tele-screening as currently performed with the available tools is still not capable of completely replacing a standard ophthalmic examination for the assessment of ocular surface diseases. While waiting for new emerging technologies and future implementation of imaging modalities and artificial intelligence, decision making algorithms can help eye-practitioners remotely screen their patients to assess the optimal time for follow-up appointments.

Development and Validation of an Open-Source Grading Tool for Outcome Assessment in Limbal Stem Cell Treatment.

PURPOSE: To design a grading system and validate an open-source tool to improve objective quantification and follow-up of limbal stem cell deficiency (LSCD) after treatment. METHODS: A custom-made web-based grading system was developed for grading stem cell deficient eyes, termed the "Vascularisation, Haze, and Integrity" tool. For validation purposes, 60 corneal slit-lamp images of 30 limbal stem cell deficient eyes were graded by 3 groups of examiners: 3 corneal specialists (group A), 3 ophthalmologists with an expertise other than cornea (group B), and 3 nonclinicians (group C). The intragrader and intergrader agreement was evaluated using Fleiss weighted kappa coefficients and concurrent assessment of interrater and intrarater reliability (IRR) coefficients. RESULTS: The overall intergrader agreement was 0.78, 0.61, and 0.42 for superficial corneal vascularization, corneal haze, and epithelial integrity, respectively. All groups had good agreement for the vascularization parameter with the highest intergrader reliability in group A (IRR = 0.80) and the lowest in group C (IRR = 0.72). When assessing "haze," there was good agreement in groups A (IRR = 0.75) and B (IRR = 0.76) but low agreement in group C (IRR = 0.37). CONCLUSIONS: We report the development and evaluation of a novel method for grading results of limbal stem cell deficient eyes after treatment and provide this system as a free, open-source online tool. The grading tool offers an easy and standardized way of assessing the corneal surface in patients with LSCD, enables evaluation of progression over time, reduces assessment bias, and-if adopted universally-will harmonize outcome being reported between groups.

Assessment of Corneal and Lens Density in Children With Celiac Disease.

PURPOSE: To assess the early changes of corneal and lens density in a pediatric population with celiac disease. METHODS: One hundred one patients were included in this observational and prospective study. Patients with celiac disease formed the celiac disease group. Healthy individuals with no medical history formed the control group. Corneal and lens density were assessed with Pentacam HR (Oculus Optikgeräte GmbH, Wetzlar, Germany). RESULTS: The mean lens and corneal density outcomes in all zones did not differ between groups (P > .05 for each). Maximum lens density outcome was significantly higher in the celiac disease group than in the control group (P = .028). The mean corneal density at the peripheral cornea was significantly higher in females than males in the celiac disease group (P < .05 for each). Compliance with a gluten-free diet, body mass index, and histological classification of celiac disease had no significant effect on lens and corneal density in patients with celiac disease (P > .05 for each). CONCLUSIONS: Celiac disease did not affect the mean lens and corneal density in this pediatric population, but higher maximum lens density in patients with celiac disease and higher peripheral corneal density in female patients with celiac disease may indicate early stages of ocular involvement of celiac disease. [J Pediatr Ophthalmol Strabismus. 2019;56(6):402-406.].

Rapid Assessment of Avoidable Blindness: looking back, looking forward.

The Rapid Assessment of Avoidable Blindness, or RAAB, is a relatively simple and low-cost survey methodology to provide data on the prevalence and causes of visual loss. The aim of this article is to reflect on the achievements and challenges of RAAB, and to describe the future developments that are needed to ensure that it remains a relevant and widely used tool. To date, at least 331 RAABs have been undertaken in 79 countries, and these surveys provide an important source of information on visual loss at both the local and global level. A RAAB repository has been developed which includes the site and date of RAABs undertaken, and, where authors have agreed, the core indicators, reports or even raw data from the survey. This dataset has already been used for meta-analyses, and there are further opportunities for its use. Despite these achievements, there are core areas in which RAAB needs to be strengthened so that the full benefits of undertaking the survey can be reaped. Key developments of RAAB are underway, and will include greater use of mobile technologies using a cloud-based platform to enable both digital data collection, real-time survey reviews, reporting and analysis, and a greater emphasis on using the data for planning.

In vivo confocal microscopy and optical coherence tomography as innovative tools for the diagnosis of limbal stem cell deficiency.

The limbus is the anatomical and functional barrier between the corneal and conjunctival epithelia. It is characterized by the presence of the limbal stem cell niche, which allows corneal homeostasis to be maintained. Limbal stem cell deficiency is characterized by a dual process: insufficient regeneration of corneal epithelium, which cannot therefore assure its function of physiological support, associated with corneal invasion by conjunctival proliferation. Diagnosis is currently made via routine clinical examination, corneal impression cytology and in vivo confocal microscopy (IVCM). Slit lamp examination shows abnormal limbal anatomy, thin and irregular epithelium with late fluorescein staining, and superficial vascularization. With its high resolution, IVCM allows identification of limbal and corneal epithelial changes at a cellular level in en face views parallel to the corneal surface, but with a restricted viewing field of the corneal surface. It shows a poor transition between the corneal and conjunctival epithelia, associated with a loss of the normal corneal epithelial stratification, low basal cell and sub-basal nerve plexus densities, and subepithelial fibrosis. Spectral domain optical coherence tomography of the central cornea and limbus, with scans in variable orientations, allows a quick, global and non-invasive analysis of normal eyes and those with limbal stem cell deficiency. It shows a thin limbal epithelium, lacking normal thickening, featuring absence of stromal undulations and limbal crypts in cross-sections and sections parallel to the limbus, lack of visible limbal crypts in en face sections, loss of clear transition between the hyporeflective corneal epithelium and the hyperreflective conjunctival epithelium, and hyperreflective subepithelial fibrosis. The limbus is the anatomical and functional barrier between the corneal and conjunctival epithelia. It is characterized by the presence of the limbal stem cell niche, which allows corneal homeostasis to be maintained. Limbal stem cell deficiency (LSCD) is characterized by a dual process: insufficient regeneration of corneal epithelium, which cannot therefore assure its function of physiological support, associated with corneal invasion by conjunctival proliferation.

Cornea and anterior eye assessment with slit lamp biomicroscopy, specular microscopy, confocal microscopy, and ultrasound biomicroscopy.

Current corneal assessment technologies make the process of corneal evaluation extremely fast and simple, and several devices and technologies show signs that help in identification of different diseases thereby, helping in diagnosis, management, and follow-up of patients. The purpose of this review is to present and update readers on the evaluation of cornea and ocular surface. This first part reviews a description of slit lamp biomicroscopy (SLB), endothelial specular microscopy, confocal microscopy, and ultrasound biomicroscopy examination techniques and the second part describes the corneal topography and tomography, providing up-to-date information on the clinical recommendations of these techniques in eye care practice. Although the SLB is a traditional technique, it is of paramount importance in clinical diagnosis and compulsory when an eye test is conducted in primary or specialist eye care practice. Different techniques allow the early diagnosis of many diseases, especially when clinical signs have not yet become apparent and visible with SLB. These techniques also allow for patient follow-up in several clinical conditions or diseases, facilitating clinical decisions and improving knowledge regarding the corneal anatomy.

Development and Assessment of a Novel Canine Ex Vivo Corneal Model.

PURPOSE: To develop a novel ex vivo extended culture model of canine corneal epithelial cell wound healing. MATERIALS AND METHODS: Canine corneoscleral rims (CSR) were obtained and, after preparation for culture, were placed on a nutating scaffold and incubated in physiological conditions. In experiment 1, eight CSR in a serum-containing antimicrobial-fortified medium were monitored for epithelial integrity and bacterial infection up to 28 days in culture. CSR were assessed histologically at the end of the culture period end points 0, 7, 14, and 28 days with accompanying scanning electron microscopic (SEM) and transmission electron microscopic (TEM) evaluation. Samples for microbial culture were obtained at days 0, 3, 7, 14, and 28. In experiment 2, uniform 8-mm-diameter superficial corneal epithelial wounds were created and monitored for re-epithelialization in the same culture conditions or in a serum-free protein equivalent medium, with four CSR per group. Standardized digital images were obtained with cobalt filter at the time of fluorescein staining and media change every six hours. Image J imaging software was used to measure the area of fluorescein retention. Re-epithelialization rates were calculated and CSR then fixed for immunohistochemistry (IHC). RESULTS: All corneas survived to end points as described in experiment 1 with no evidence of contamination or compromised epithelial integrity. Histologically, a multilayered epithelium was maintained and corneal edema was not appreciated until day 14. SEM examination revealed epithelial cell layer confluence and migrating epithelial cells of normal cellular morphology with normal cell-cell interactions on TEM. In experiment 2, all eight corneas healed with a healing rate of 0.702 ± 0.130 mm2/h (1.25 mm/day epithelial cell migration rate) and were positive in IHC evaluation for markers of corneal fibrosis. CONCLUSION: This ex vivo canine corneal wound healing model is an appropriate and clinically relevant tool for assessment and modulation of epithelial wound healing.

Multimodal Assessment of Corneal Thinning Using Optical Coherence Tomography, Scheimpflug Imaging, Pachymetry, and Slit-Lamp Examination.

PURPOSE: To assess the relationship between corneal thinning measured by clinician-graded slit-lamp examination compared with ultrasound pachymetry (USP), anterior segment optical coherence tomography (AS-OCT), and the Pentacam. METHODS: Patients with corneal thinning underwent USP, AS-OCT, Pentacam measurements and standardized clinical grading by 2 cornea specialists estimating thinning on slit-lamp examination. Reproducibility of each testing modality was assessed using the intraclass correlation coefficient. Bland-Altman plots were used to determine precision and limits of agreement (LOA) between imaging modalities and clinical grading. RESULTS: We included 22 patients with corneal thinning secondary to infectious or inflammatory keratitis. Mean percent stromal thinning estimated by grader 1 was 51% (SD 31) and grader 2 was 49% (SD 33). The intraclass correlation coefficient between the masked examiners was 0.95 (95% confidence interval, 0.88-0.98). Graders were more similar to each other than to any other modality with 2% difference and 4.6% of measurements outside the LOA. When measuring the area of maximum thinning, AS-OCT measured approximately 10% thicker than human graders while the Pentacam measured approximately 10% thinner than human graders with 16.7% outside the LOA. USP measured approximately 20% thinner than human graders with 5.6% outside the LOA. CONCLUSIONS: Trained corneal specialists have a high degree of agreement in location and degree of corneal thinning when measured in a standardized fashion on the same day. Other testing modalities had acceptable reproducibility and agreement with clinical examination and each other, although Scheimpflug imaging fared worse for corneal thinning, particularly in the periphery, than the other modalities.

Incidence, Risk Factors, and Surgical Management of Boston Type 1 Keratoprothesis Corneal Melts, Leaks, and Extrusions.

PURPOSE: To determine the rate of Boston type 1 keratoprosthesis (Kpro)-related corneal melts, leaks, and extrusions requiring surgical repair and to analyze possible risk factors and visual outcomes. METHODS: Retrospective chart review of 110 patients (128 eyes) who received a Kpro between November 2004 and December 2010 (average follow-up of 29 mo). The rate of corneal complications, risk factors for melts, and postmelt repair visual outcomes were evaluated. RESULTS: Twenty eyes from 18 patients developed Kpro-related melts requiring surgical repair. The incidence of melt-related complications was 16%. In total, there were 33 episodes of melt-related complications. Surgical repair included lamellar patch grafts (15), Kpro removal with penetrating keratoplasty (7), reassembly of Kpro onto a new cornea (4), replacement of Kpro (3), suturing of a leak (3), and enucleation (1). The majority of eyes (18/20) did not regain their best post-Kpro vision at final follow-up (average 10 mo and range, 1-36 mo after melt repair). Significant risk factors for melt included previous infectious keratitis [P < 0.0001, odds ratio (OR) = 12.50, 95% confidence interval (CI), 4.02-38.9] and conjunctival deficiency (ie, a diagnosis of Stevens-Johnson syndrome, mucous membrane pemphigoid, or chemical injury, P = 0.043, OR = 2.66, CI, 1.01-7.02). CONCLUSIONS: Patients who undergo Kpro with severe ocular surface disease are at greater risk for corneal melts, leaks, and extrusions. Patients with infectious keratitis and conjunctival deficiency are at an increased risk of developing corneal melts. Visual outcomes are poor after surgical repair of these complications.

Validity and Reliability of a Novel Ocular Pain Assessment Survey (OPAS) in Quantifying and Monitoring Corneal and Ocular Surface Pain.

PURPOSE: To validate the Ocular Pain Assessment Survey (OPAS), specifically designed to measure ocular pain and quality of life for use by eye care practitioners and researchers. DESIGN: A single-center cohort study was conducted among patients with and without corneal and ocular surface pain at initial and follow-up visits over a 6-month period. The content of the OPAS was guided by literature review, a body of experts, and incorporating conceptual frameworks from existing pain questionnaires. The Wong-Baker FACES Pain Rating Scale served as the gold standard for measuring the intensity of ocular pain. PARTICIPANTS: A total of 102 patients aged 18 to 80 years completed the OPAS at the initial visit. A total of 21 patients were followed up after treatment. METHODS: Indices of validity and internal consistency (Spearman's rank-order, rs, or Pearson's correlation coefficients, rp), and coefficient of reliability (Cronbach's α) were determined in addition to equivalence testing, exploratory factor analysis (EFA), and diagnostic analysis. MAIN OUTCOME MEASURES: Eye pain intensity was the primary outcome measure, and interference with quality of life (QoL), aggravating factors, associated factors, associated non-eye pain intensity, and self-reported symptomatic relief were the secondary outcome measures. RESULTS: The OPAS had criterion validity at both initial (rs = 0.71; n = 102; P < 0.01) and follow-up visits (rs = 0.97; n = 21; P < 0.01). Equivalence tests yielded OPAS and gold standard equivalence for both the initial and follow-up visits. The EFA supported 6 subscales (eye pain intensity at 24 hours and 2 weeks, non-eye pain intensity, QoL, aggravating factors, and associated factors) confirming multidimensionality. Cronbach's α >0.83 for all subscales established strong internal consistency, which correlated with the gold standard, including 24-hour eye pain intensity and QoL interference scores (rp = 0.81, 0.64, respectively P < 0.001). At follow-up, reduction in pain scores was accompanied by improvement in all dimensions of the OPAS. Percentage change in QoL correlated to percentage change in the gold standard (rp = 0.53; P < 0.05). The OPAS was sensitive (94%), specific (81%), and accurate (91%), with a diagnostic odds ratio >50. CONCLUSIONS: The OPAS is a valid, reliable, and responsive tool with strong psychometric and diagnostic properties in the multidimensional quantification of corneal and ocular surface pain intensity, and QoL.

Polarimetric Interferometry for Assessment of Corneal Stromal Lamellae Orientation.

PURPOSE: To analyze corneal stromal lamellae orientation in normal subjects and patients with various corneal conditions using a polarimetric interferometer. METHODS: Thirty-two healthy control subjects (59 eyes) and 16 patients (22 eyes) with corneal conditions or postkeratoplasty were included in the study. All patients were imaged using the interferometer and slit lamp photography. The interferometer produces an orthogonal cross-like image of stromal lamellae by illuminating the cornea in phase-light polarization angle. Corneal haze was graded on a scale from 0 to 4. Interferometer cross-like images were graded on a scale from 0 to 5 by a masked observer. Keratometry, corneal central pachymetry, and optical densitometry were obtained with Scheimpflug corneal tomography. RESULTS: The cross-like image was observed in 31 of 32 healthy control subjects (58 of 59 eyes) and in 13 of 16 patients (19 of 22 eyes). The image was not detectable in 3 patients, 1 with total corneal neovascularization and scarring, 1 with central leukoma, and 1 with failed deep lamellar keratoplasty. Corneal haze was the main factor obscuring the cross-like image (P < 0.05). Clarity of the images was influenced by older age, steeper keratometry, higher pachymetry, and optical density (P < 0.05). There was no correlation between the orientation of the keratometric axes and the orientation of the 2 arms of the cross-like image (P > 0.05). CONCLUSIONS: Corneal stromal lamellae orientation can be efficiently assessed and displayed as a cross-like image by the polarimetric interferometer. Stromal lamellae orientation imaging may have potential implications in corneal diagnostics and surgery.

The epidemiology, clinical characteristics, histopathology and management of juvenile- and adult-onset corneoscleral limbus xanthogranuloma.

PURPOSE: Adult-onset xanthogranuloma (AOX) of the corneoscleral limbus is a rare inflammatory condition of unknown aetiology. Similar to limbal juvenile xanthogranuloma (JXG), it presents as a growing mass at the corneoscleral junction. Limbal AOX and JXG can lead to sight-threatening complications if not managed in a timely manner. This systematic review summarises the main clinical and histopathological features of limbal AOX/JXG and discusses the management of this uncommon disease. METHODS: We performed a literature search in the MEDLINE database for all historical entries, using the search terms "limbus", "limbal" and "xanthogranuloma", and retrieved all articles reporting on limbal xanthogranuloma. After refining the search to articles relevant to limbal AOX, we were able to identify ten adult cases of limbal AOX and compare those with all reported cases of limbal JXG. RESULTS: Clinically, AOX usually presents as an isolated smooth, yellowish, dome-shaped nodule at the corneoscleral junction, similar to an ocular presentation of JXG, with which it also shares similar histopathological features. CONCLUSION: Limbal JXG and AOX may represent the same disease entity. Diagnosis relies on the clinical presentation, pathology and immunohistochemical profile. Spontaneous regression is unlikely, and thus prompt surgical intervention should be considered to prevent sight-threatening complications. Xanthogranuloma should be included in the differential diagnosis of corneoscleral limbal masses in patients of all age groups.

Objective assessment of corneal staining using digital image analysis.

PURPOSE: To validate a new objective digital image analysis technique to evaluate corneal staining. METHODS: One hundred photographs of corneal staining from various ocular surface diseases in 100 patients were quantified by a new strategy: a combination of the difference of Gaussians (DoG) edge detection for morphologic properties of corneal erosions and the red-green-blue (RGB) systems and hue-saturation-value (HSV) color model for detection of color. To enhance the image, we adopted a median filter, Otsu thresholding, and contrast-limited adaptive histogram equalization (CLAHE). To validate the diagnostic value of this new strategy, the same photographs were also graded by two independent clinicians using the Oxford scheme and the National Eye Institute/Industry (NEI)-recommended guidelines. The correlation between the average subjective grade and objective image analysis measurement was evaluated using the Pearson's correlation coefficient. RESULTS: The new algorithm showed a strong correlation with the clinical grading scale in the Oxford scheme and the NEI-recommended guidelines (R = 0.850 and 0.903, P < 0.001, respectively). The repeatability of the objective measurement was excellent (R = 0.994). CONCLUSIONS: The new algorithm showed excellent correlation with the traditional subjective clinical grading scales. It may be useful for objective assessment of corneal staining, independent of disease conditions.

Corneal assessment technologies: current status.

There are now many devices that acquire data about the cornea: shape, power, pachymetry at any desired point of the cornea, corneal hysteresis, flap thickness (in LASIK procedures), endothelial cell count and morphology, and so forth. We review the literature on corneal assessment techniques and devices available in clinical practice. Specifically, we discuss slit lamp biomicroscopy, specular microscopy, ultrasound pachymetry, confocal microscopy, very-high-frequency digital ultrasound biomicroscopy, optical coherence tomography, Placido disk-based keratoscopy, slit-scanning elevation topography, Scheimpflug imaging, and dynamic applanation procedures-all of which can be used to assess the morphology of the cornea. In addition, we present a critical analysis of the instrumentation described and discuss the necessity of developing new technology for assessing both the morphology and the physiology of the cornea.

Assessment of the use of spectral domain optical coherence tomography (SD-OCT) for evaluation of the healthy and pathological cornea in dogs and cats.

PURPOSE: Morphologic evaluation of the cornea is based on the slit-lamp examination. In human ophthalmology, optical coherence tomography (OCT) has opened a new field in the clinical approach to anterior segment disorders and more specifically the cornea. The aim of our study is to describe spectral domain OCT examination of the cornea in dogs and cats in clinical practice conditions. MATERIAL AND METHODS: One hundred eyes were examined from 52 dogs and 41 cats presented to a private practice referral center with an Optovue iVue SD-OCT device. Sixteen healthy animals were used as control group, and the others were examined for various corneal conditions. All animals were examined after sedation or anesthesia. RESULTS: Normal and pathological aspects of canine and feline cornea were described for various conditions such as corneal ulcers, microbial keratitis, corneal sequestrum, infiltrations, foreign bodies, corneal dystrophies, and surgical conditions. CONCLUSION: SD-OCT examination of normal and pathological corneal conditions in dogs and cats gave an accurate evaluation of each component of the cornea. The advantage of the technique is the in vivo, real-time evaluation of all corneal layers with the absence of corneal contact. Constraints included the necessity of sedation for precise focus and the low quality of images obtained with too pigmented or thickened corneas.