Infectious crystalline keratopathy-clinical-microbiological profile and outcome of management.

PURPOSE: To describe the clinical features, management, and long-term outcome of Infectious crystalline keratopathy (ICK). METHODS: The medical records of clinically diagnosed and microbiologically proven cases of ICK were reviewed from January 2011 to December 2022. Clinical characteristics include the presence of whitish needle-like projections with branching, limited to anterior-mid stroma. Keratoplasty being the most common risk factor, graft-related microbial keratitis during the same period was also studied. The demography, clinical profile, microbiology, treatment, and outcome were analyzed, and compared with secondary graft infiltrate(GI). RESULTS: Medical records of 24 cases with ICK were reviewed. The mean age was 49.3 ± 20.1 years, with 15(62.5%) males. Prior keratoplasty was done in 18 (75%) cases, with a mean graft size of 10.1 ± 1.5 mm, and mean interval between the last graft and presentation was 9.7 ± 6.2 (3-90) months. In comparison to GI (n = 24), ICK patients (n = 18,75%) were less symptomatic, presented late (7.3 ± 6.5 days vs 16.3 ± 19.4, p = 0.003), using frequent topical steroids (> 3 times/day, p = 0.006), smaller infiltrate size < 4 mm (p = 0.008), central (p = 0.02), less associated with epithelial defect (p = 0.0001), hypopyon (p = of 0.0002), corneal perforation (p = 0.0006), and surgical management (p = 0.03). On microbiology, 22 (91.6%) ICK cases were culture positive, 14 (63.6%) gram-positive, 3 (13.6%) gram-negative, 2 (9%) mixed bacteria, and 3 (13.6%) fungus, comparable with GI. CONCLUSION: ICK affects poor ocular surfaces usually following keratoplasty with larger graft size, the use of steroids being the most common association, and it responds to medical management as compared to GI.

Progressive conjunctival invasion of cornea in a child with Warburg-Cinotti Syndrome: a case report.

BACKGROUND: Warburg-Cinotti syndrome is a rare syndrome caused by de novo or inherited variants in discoding domain receptor tyrosine kinase 2 (DDR2). Only six cases have been reported worldwide and our knowledge of this disease remained sparse especially from an ophthalmological perspective, since previous literature mostly focused on systemic malformations or genetics. CASE PRESENTATION: A seven-year-old boy developed a gelatinous vascularized conjunctiva-like mass secondary to trauma. The mass enlarged and gradually invaded the cornea. With each surgical intervention, the mass recurred and grew even larger rapidly. The patient ended up with the mass covering the entire cornea along with symblepharon formation. Whole exome sequencing revealed a hemizygous variant in the DDR2 gene, which is consistent with Warburg-Cinotti syndrome. CONCLUSIONS: Considering Warburg-Cinotti syndrome, we should be vigilant of patients exhibiting progressive conjunctival invasion of the cornea, even those without systemic manifestations or a positive family history.

Analysis of the performance of the CorneAI for iOS in the classification of corneal diseases and cataracts based on journal photographs.

CorneAI for iOS is an artificial intelligence (AI) application to classify the condition of the cornea and cataract into nine categories: normal, infectious keratitis, non-infection keratitis, scar, tumor, deposit, acute primary angle closure, lens opacity, and bullous keratopathy. We evaluated its performance to classify multiple conditions of the cornea and cataract of various races in images published in the Cornea journal. The positive predictive value (PPV) of the top classification with the highest predictive score was 0.75, and the PPV for the top three classifications exceeded 0.80. For individual diseases, the highest PPVs were 0.91, 0.73, 0.42, 0.72, 0.77, and 0.55 for infectious keratitis, normal, non-infection keratitis, scar, tumor, and deposit, respectively. CorneAI for iOS achieved an area under the receiver operating characteristic curve of 0.78 (95% confidence interval [CI] 0.5-1.0) for normal, 0.76 (95% CI 0.67-0.85) for infectious keratitis, 0.81 (95% CI 0.64-0.97) for non-infection keratitis, 0.55 (95% CI 0.41-0.69) for scar, 0.62 (95% CI 0.27-0.97) for tumor, and 0.71 (95% CI 0.53-0.89) for deposit. CorneAI performed well in classifying various conditions of the cornea and cataract when used to diagnose journal images, including those with variable imaging conditions, ethnicities, and rare cases.

Research progress on measurement methods and clinical applications of corneal elastic modulus.

Various corneal diseases are strongly associated with corneal biomechanical characteristics, and early measurement of patients' corneal biomechanics can be utilized in their diagnosis and treatment. Measurement methods for corneal biomechanical characteristics are classified into ex vivo and in vivo. Some of these methods can directly measure certain corneal biomechanical parameters, while others require indirect calculation through alternative methods. However, due to diversities in measurement techniques and environmental conditions, significant differences may exist in the corneal mechanical properties measured by these two methods. Therefore, comprehensive research on current measurement methods and the exploration of novel measurement techniques may have great clinical significance. The corneal elastic modulus, a critical indicator in corneal biomechanics, reflects the cornea's ability to return to its initial shape after undergoing stress. This review aims to provide a comprehensive summary of the corneal elastic modulus, which is a critical biomechanical parameter, and discuss its direct, indirect, and potential measurement methods and clinical applications.

Efficacy and Safety of the Modified Cretan Protocol in Patients with Post-LASIK Ectasia

Objectives: To investigate the clinical efficacy and safety of the modified Cretan protocol in patients with post-laser in situ keratomileusis ectasia (PLE). Materials and Methods: In this retrospective study, 26 eyes of 16 patients with PLE were treated with the modified Cretan protocol (combined transepithelial phototherapeutic keratectomy and accelerated corneal collagen cross-linking). Visual, refractive, tomographic, and aberrometric outcomes and point spread function (PSF) were recorded preoperatively and at 6, 12, and 24 months after treatment. Results: Both uncorrected and best corrected visual acuity were stable at 24 months postoperatively compared to baseline (from 0.89±0.36 to 0.79±0.33 logarithm of the minimum angle of resolution [LogMAR] and 0.31±0.25 to 0.24±0.19 LogMAR, respectively, p>0.05 for all values). The mean K1, K2, Kmean, thinnest corneal thickness, and spherical aberration at baseline were 45.76±5.75 diopters (D), 48.62±6.17 D, 47.13±5.89 D, 433.16±56.86 µm, and -0.21±0.63 µm respectively. These values were reduced to 42.86±6.34 D, 45.92±6.74 D, 44.21±6.4 D, 391.07±54.76 µm, and -0.51±0.58 µm at 24 months postoperatively (p<0.001, p=0.002, p<0.001, p=0.001, and p=0.02, respectively). The mean spherical equivalent, manifest cylinder, Kmax, central corneal thickness, other corneal aberrations (root mean square, trefoil, coma, quatrefoil, astigmatism), and PSF remained stable (p>0.05 for all variables), while anterior and posterior elevation were significantly improved at 24 months postoperatively (p<0.001 and p=0.02, respectively). No surgical complications occurred during the 24-month follow-up. Conclusion: The modified Cretan protocol is a safe and effective treatment option for PLE patients that provides visual stabilization and significant improvement in topographic parameters during the 24-month follow-up. Further studies are needed to support our results.

Objective Analysis of Corneal Nerves and Dendritic Cells. / Objektive Analyse von Hornhautnerven und dendritischen Zellen.

Corneal nerves and dendritic cells are increasingly being visualised to serve as clinical parameters in the diagnosis of ocular surface diseases using intravital confocal microscopy. In this review, different methods of image analysis are presented. The use of deep learning algorithms, which enable automated pattern recognition, is explained in detail using our own developments and compared with other established methods.

Efficacy of topical 5-Fluorouracil in the management of ocular surface squamous neoplasia: a study of 101 eyes.

OBJECTIVE: To study the efficacy and side-effect profile of topical 5-Fluorouracil (5-FU) in the treatment of ocular surface squamous neoplasia (OSSN). METHODS: Retrospective study of 101 eyes of 100 patients treated with 5-FU with one week on and 3 weeks off regimen. RESULTS: Of the 100 patients (101 eyes), the mean age at diagnosis of OSSN was 49 (median, 52 years; range, 11-87 years). History of prior intervention was noted in 6 (6%) eyes. Tumor epicenter included bulbar conjunctiva (n = 54; 53%), limbus (n = 27; 27%), and cornea (n = 20;20%). Mean number of cycles of topical 5-FU administered was 3 (median, 3; range, 1-8). Complete tumor regression was achieved with topical 5-FU in 89 (88%) eyes with a mean number of 2 cycles (median, 2; range, 1-6) of 5-FU. The remaining 12 (12%) lesions underwent additional treatment including excisional biopsy (n = 7), extended enucleation (n = 3), and topical Interferon alpha 2b (n = 2) for complete tumor control. Over a mean follow-up period of 6 months (median, 5 months; range, 1-36 months) following treatment, tumor recurrence was noted in 2 (2%) patients, and side-effects were noted in 7 (7%) eyes including conjunctival hyperemia (n = 1), punctal stenosis (n = 1), sterile keratitis (n = 4), and limbal stem cell deficiency (n = 1). CONCLUSION: Topical 5-FU is an effective non-invasive therapy for OSSN with a minimal side-effect profile.

Paraproteinaemic keratopathy simulating a crystalline keratopathy.

BACKGROUND: Paraproteinemic keratopathy is a rare disorder characterized by the bilateral accumulation of polychromatic deposits diffusely in all corneal layers together or not with diffuse or patchy pseudo lipid deposits. We present an atypical case of paraproteinemic keratopathy which lead to an initial misdiagnosis of infectious crystalline keratopathy. CASE PRESENTATION: a 69-year-old woman with an asymptomatic keratopathy detected during a cataract intervention. Slit-lamp examination revealed several hyper refringent subepithelial foci with fern-shaped branches, resembling crystalline keratopathy, in her left eye. Anterior segment optical coherence tomography revealed exclusively subepithelial hyperreflective lesions limited to the anterior stroma. The progressive bilateralization and progression of the condition prompted us to include other entities with crystalline corneal deposits in our differential diagnosis. Hematological analysis showed a high number of free Kappa light chains. Despite the typical clinical appearance of crystalline keratopathy, the atypical evolution and test results led us to consider that monoclonal gammopathy could be the cause of this entity. CONCLUSIONS: Paraproteinemic keratopathy may present in its early stages as a unilateral subepithelial crystalline keratopathy. Thus, it must always be taken into account in the differential diagnosis of any crystalline keratopathy, particularly when there are no predisposing factors for an infectious crystalline keratopathy. Early recognition of this rare entity is important to address the associated potentially serious systemic disease.

Lid-wiper keratopathy and mucous membrane grafting.

BACKGROUND: A healthy lid-wiper is an important component of a healthy ocular surface. Any abnormality or irregularity of the lid wiper can potentially damage a relatively healthy ocular surface. Stevens-Johnson syndrome, toxic epidermal necrolysis, and ocular cicatricial pemphigoid are some of the examples that can result in lid-margin keratinization during the course of the disease. These permanent changes at the lid margin mechanically abrade the corneal surface and facilitate corneal neovascularization. The corneal clarity is lost over time, and the patients have corneal blindness. PURPOSE: This video discusses the role of a healthy lid-wiper, conditions causing lid-margin keratinization and subsequent lid-wiper keratopathy, and surgical technique in mucous membrane grafting. SYNOPSIS: The video demonstrates the technique of restoration of a healthy lid margin by doing a mucous membrane graft for lid-margin keratinization and its role in the prevention of corneal blindness. HIGHLIGHTS: Lid-margin keratinization is essentially a chronic sequela and is often ignored till irreversible corneal changes develop. Early intervention in the form of mucous membrane grafting can prevent corneal vascularization and loss of corneal clarity. VIDEO LINK: https://youtu.be/NGMlqUp_qLU.

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.].

[Modern techniques and features of selective keratoplasty]. / Sovremennye tekhnologii i vozmozhnosti selektivnoi keratoplastiki.

Selective keratoplasty involves replacing the affected layers of the cornea with similar donor tissue. In case of pathological changes in the middle and posterior stroma, deep anterior lamellar keratoplasty (DALK) is performed. Chronic corneal edema caused by endothelial dysfunction is an indication for endothelial keratoplasty - Descemet membrane endothelial keratoplasty (DMEK) or Descemet Stripping Endothelial Keratoplasty (DSAEK). Compared to penetrating keratoplasty (PK), these operations are characterized by a low risk of damage to intraocular structures and a relatively short rehabilitation period. Complications of selective keratoplasty include the formation of a false chamber between the lamellar graft and the recipient's cornea, ocular hypertension during anterior chamber air tamponade. Persistent epithelial defect can be a sign of primary graft failure in DALK, DSAEK and DMEK. Selective keratoplasty is characterized by a lower incidence of immune rejection than PK. In some cases, DALK can be complicated by corneal changes related to suture fixation of the graft. Long-term postoperative use of topical glucocorticoids can cause ocular hypertension and cataracts.

Corneal neuropathic pain: a review to inform clinical practice.

Corneal neuropathic pain (CNP) is a poorly defined disease entity characterised by an aberrant pain response to normally non-painful stimuli and categorised into having peripheral and central mechanisms, with the former responding to instillation of topical anaesthetic. CNP is a challenging condition to diagnose due to numerous aetiologies, an absence of clinical signs and ancillary tests (in vivo confocal microscopy and esthesiometry), lacking the ability to confirm the diagnosis and having limited availability. Symptomatology maybe mirrored by severe and chronic forms of dry eye disease (DED), often leading to misdiagnosis and inadequate treatment. In practice, patients with suspected CNP can be assessed with questionnaires to elicit symptoms. A thorough ocular assessment is also performed to exclude any co-existent ocular conditions. A medical and mental health history should be sought due to associations with autoimmune disease, chronic pain syndromes, anxiety and depression. Management begins with communicating to the patient the nature of their condition. Ophthalmologists can prescribe topical therapies such as autologous serum eyedrops to optimise the ocular surface and promote neural regeneration. However, a multi-disciplinary treatment approach is often required, including mental health support, particularly when there are central mechanisms. General practitioners, pain specialists, neurologists and psychologists may be needed to assist with oral and behavioural therapies. Less data is available to support the safety and efficacy of adjuvant and surgical therapies and the long-term natural history remains to be determined. Hence clinical trials and registry studies are urgently needed to fill these data gaps with the aim to improve patient care.