Collagen Fibrils and Proteoglycans of Macular Dystrophy Cornea: Ultrastructure and 3D Transmission Electron Tomography.

We report the ultrastructure and 3D transmission electron tomography of collagen fibrils (CFs), proteoglycans (PGs), and microfibrils within the CF of corneas of patients with macular corneal dystrophy (MCD). Three normal corneas and three MCD corneas from three Saudi patients (aged 25, 31, and 49 years, respectively) were used for this study. The corneas were processed for light and electron microscopy studies. 3D images were composed from a set of 120 ultrastructural images using the program "Composer" and visualized using the program "Visuliser Kai". 3D image analysis of MCD cornea showed a clear organization of PGs around the CF at very high magnification and degeneration of the microfibrils within the CF. Within the MCD cornea, the PG area in the anterior stroma was significantly larger than in the middle and posterior stroma. The PG area in the MCD cornea was significantly larger compared with the PG area in the normal cornea. The CF diameter and inter-fibrillar spacing of the MCD cornea were significantly smaller compared with those of the normal cornea. Ultrastructural 3D imaging showed that the production of unsulfated keratin sulfate (KS) may lead to the degeneration of micro-CFs within the CFs. The effect of the unsulfated KS was higher in the anterior stroma compared with the posterior stroma.

Management of Acute Corneal Hydrops Using Compression Sutures and Intracameral Air Injection.

BACKGROUND Acute corneal hydrops, a rare complication of keratoconus, is characterized by sudden onset of corneal stroma edema. It typically manifests as an acute decrease in visual acuity, accompanied by pain and photophobia. Prompt recognition and interventions are critical for effective resolution of hydrops and prevention of corneal vascularization. Herein, we present a case of a patient with keratoconus who developed corneal hydrops, successfully managed using full-thickness compression sutures and intracameral air injection. CASE REPORT A woman in her early 30s, with a history of keratoconus, presented with symptoms of acute hydrops in her left eye. On presentation, best corrected visual acuity was hand motion. Slit-lamp examination revealed marked corneal edema with multiple stromal clefts. The decision was made to perform full-thickness compression sutures combined with intracameral air injection to expedite edema resolution and prevent neovascularization. Three full-thickness sutures were placed across Descemet membrane breaks, and an air bubble was left, filling 50% of the anterior chamber. At 3-month follow-up, a clear, compact cornea was noted, with no evidence of vascularization. The patient was scheduled for penetrating keratoplasty for visual rehabilitation. CONCLUSIONS The combination of full-thickness compression sutures and intracameral air seems to be an effective and safe method for preventing corneal angiogenesis following hydrops. As corneal scaring is often an inevitable complication of acute corneal hydrops, keratoplasty is necessary for improving visual acuity. Hence, the prevention of corneal vascularization should be the major aim in the management of corneal hydrops to ensure successful keratoplasty.

Exploring awareness of cataract and associated risk factors: A cross-sectional study among the adult population in Jazan, Saudi Arabia.

Cataracts are a leading cause of visual impairment globally and significantly affect quality of life. In the Jazan region of Saudi Arabia, an area characterized by unique environmental and socioeconomic factors, the awareness of the cataract and its associated risk factors remain poorly understood. Therefore, assessing the knowledge about this problem in our region is the initial step to mitigate the impact of cataracts in the region. This descriptive cross-sectional study evaluated the prevalence of cataracts and the associated risk factors among adults in the Jazan region of Saudi Arabia. The study employed an online questionnaire divided into the sociodemographic characteristics and cataract knowledge sections. Data were analyzed using Statistical Package for Social Sciences for descriptive statistics. The study included 701 participants, predominantly young males (64.2%, aged 18-30 years). The participant profile included students (35.7%) and teachers (16.4%), and the majority held university degrees (69.2%). The preferred sources of information were TV and social media (23.8%), the Internet (23.3%), and academic studies (10.9%). Regarding cataract awareness, 57.6% correctly identified cataracts, 64.9% recognized blurred vision as a symptom, and 68.8% were aware of surgical treatment. Notable associations were found with sex (84.1% of females with higher education, P = .039), age (90.4% of those with >50 years of education, P = .002), and occupation (93.2% of students, P < .001). Overall, there were significant associations between the knowledge level and age (67.3%, P < .001) and occupation (77.6%, P < .001). This study revealed a moderate level of awareness of cataracts in Jazan, with significant variations based on sex, age, and occupation. These findings highlight the need for targeted educational interventions, particularly among certain demographic groups, to enhance understanding and management of cataracts in the region.

Splinter Cataract in Patients with Keratoconus and Frequent Eye Rubbing: A Novel Finding.

BACKGROUND Patients with keratoconus are at increased risk of developing cataract at a younger age compared to the normal population. Predisposing factors include atopy and topical steroid use. In this case series we report the novel observation of splinter-shaped cortical cataract in 16 eyes of 14 patients with keratoconus in the absence of other risk factors of cataract development from a single center in Riyadh, Saudi Arabia. CASE REPORT This is a retrospective review of 16 eyes of 14 patients diagnosed with keratoconus and found to have splinter cortical cataract. Twelve patients had unilateral and 2 patients had bilateral splinter cortical cataract in the inferotemporal quadrant of the crystalline lens. Thirteen eyes (81.25%) had clinically proven keratoconus and 3 eyes (18.75%) were keratoconus suspects. All patients affirmed frequent eye rubbing and 62.5% of eyes had a history of vernal keratoconjunctivitis. Best corrected visual acuity (BCVA) by the logarithm of the minimum angle of resolution (LogMAR) was reported between 0 to 0.2 in 69% of eyes (11 eyes) and 4 eyes (25%) had BCVA of 0.3 to 0.6, and 1 eye (6%) had BCVA of 1.3. CONCLUSIONS Splinter-shaped cortical cataract could be a sign of frequent eye rubbing. Careful examination of the crystalline lens with dilated pupil may reveal peripheral cortical opacities in the inferotemporal quadrant, which can alert the physician that the patient has habitual eye rubbing and is at increased risk of keratoconus development or progression.

Visual and surgical outcomes of limbal dermoid excision at a tertiary care eye hospital.

PURPOSE: To evaluate the presenting complaints, surgical management, surgical outcomes, complications, and postoperative visual acuity following limbal dermoid excision. DESIGN: Retrospective cohort study. METHODS: Medical records of patients with limbal dermoid presenting between January 2012 and December 2020 were retrieved to extract data regarding demographics, presenting profiles including the best-corrected visual acuity (BCVA), symptoms, anterior segment examination, and refraction. The outcomes included cosmesis, complications, graft transparency, and BCVA at the last follow-up. RESULTS: Fifty-one eyes from 50 patients (27 males) were evaluated. The median age at the time of surgery was 11.5 years (interquartile range, IQR: 0.0-45.7). The median follow-up time was 5 years (IQR: 4-6). Goldenhar syndrome was noted in 5 patients (10%). The indications for surgery were cosmetic concerns (n = 20, 39%), anisometropia (n = 3, 6%), decreased vision (n = 4, 8%), and growth or Dellen formation (n = 2, 4%). Forty-eight were operated upon, opting for simple excision (n = 12, 23.5%), amniotic membrane transplantation (n = 16, 31.4%), lamellar keratoplasty (n = 15, 29.4%), and penetrating keratoplasty (n = 5, 9.8%). The most common complications were corneal scarring (n = 19, 37.2%), corneal vascularization (n = 2, 3.9%), and infection (n = 1, 2%). Astigmatism > 1 D was observed in 34 (66.7%) eyes after dermoid management (p < 0.001). There were no complications in 14 eyes (27%), BCVA was > 20/60 in 43 eyes (84.3%), and only two eyes had BCVA < 20/400. CONCLUSION: Surgical management of limbal dermoids offers promising functional and anatomic outcomes. However, postoperative astigmatism may require further follow-up and management.

Lipopolysaccharide Enhances Genotoxicity by Activating GADD45G and NF-κB in Human Corneal Epithelial Cells.

As the prevalence of microbial keratitis increases, it creates an environment conducive to genotoxicity response. A potential connection between growth arrest and DNA-damage-inducible 45 gamma (GADD45G) gene expression has not been proven in the corneal epithelial cells. The aim of this study was to determine whether lipopolysaccharide (LPS) enhances genotoxicity, DNA damage, and inflammatory responses in human corneal epithelial cells (HCECs) in vitro. In a set of parameters, cytotoxicity, reactive oxygen species, mitochondrial membrane potential, DNA damage, inflammatory response, and apoptosis were assessed. LPS (1, 5, and 10 µg/mL) treated HCECs were increased reactive oxygen species formation, mitochondrial membrane depolarization, and genotoxicity in a concentration-dependent manner. Similarly, NF-κB, PARP1, and TP53 were also overexpressed in the LPS treated HCECs. 24 hours after LPS induction, micronucleus scoring, and proapoptotic factors were also increased. Among them, the GADD45G, NF-κB, and γH2AX were overexpressed both on the mRNA and protein levels in LPS (10 µg/mL) treated HCECs. In our study, we show that the GADD45G signaling can trigger genotoxic instability in HCECs exposed to LPS. Therefore, understanding the factors contributing to infectious keratitis, such as GADD45G, NF-κB, and γH2AX signaling, may help to develop antigenotoxic and anti-inflammatory therapies for corneal dystrophy and epithelial cell remodeling.

A unique pre-endothelial layer at the posterior peripheral cornea: ultrastructural study.

This study was conducted to investigate the ultrastructure of a unique structures at the anterior side of the endothelium of the posterior peripheral cornea and compare their inner fibers to those of the limbus and sclera. The unique structures at the anterior side of endothelium was referred as a pre-endothelial (PENL) structures in the present manuscript. Ten anonymous-donor human corneoscleral rims (leftover after corneal transplants) were processed for electron microscopy. Semi-thin sections were examined using an Olympus BX53 microscope, and ultrathin sections were studied using a JOEL 1400 transmission electron microscope. A unique PENL structures was identified at the posterior peripheral cornea at a radial distance of approximately 70-638 µm, from the endpoint of Descemet's membrane. The PENL thinned out gradually and disappeared in the center. The contained an electron-dense sheath with periodic structures (narrow-spacing fibers), wide-spacing fibers, and numerous microfibrils. Typical elastic fibers were present in the sclera and limbus but were not observed in the PENL. This study revealed the existence of a new acellular PENL, containing unique fibrillar structures that were unseen in the corneal stroma. From the evidence describe in this paper we therefore suggest that PENL is a distinct morphological structure present at the corneal periphery.

Glaucoma Diagnoses and Legal Blindness from Glaucoma among Bedouin Patients of Central Saudi Arabia: A Hospital-Based Study.

PURPOSE: The current study aims to know the glaucoma diagnoses and legal blindness from glaucoma among a tertiary referral center in Riyadh (King Abdulaziz Medical City [KAMC]-Riyadh patients). METHODS: This is a retrospective cohort study on chart review, where all eligible glaucoma patients attending the ophthalmology clinic at KAMC-Riyadh, between 2018 and 2019; were included. RESULTS: A total of 248 patients were included in the study; 142 patients (57.3%) were females and 106 (42.7%) were males. The mean age of the patients was 62.2 ± 18 years and most of them (93.5%) did not have a family history of glaucoma. Nearly one-quarter (26.6%; n = 66) of the included patients were legally blind, out of those, 36.4% had their right eye affected, 34.8% had their left eye affected, and 28.8% had both eyes affected. Legally, blind patients (LBGs) did not show a statistically significant reduction in the intraocular pressure (IOP) in the right eye (P = 0.103), on comparing the IOP in both visits. Nevertheless, there was a statistically significant reduction in the IOP of the left eye among the LBGs in both visits (P = 0.016). Regarding the nonblind group of patients, there were highly statistically significant reductions in both eyes (P < 0.001). CONCLUSION: The present findings show a high prevalence rate of legal blindness among glaucoma patients, with IOP reduction, age, and glaucoma diagnoses being the most important predictors among the study population.

Late-onset spontaneous Descemet's membrane detachment post penetrating keratoplasty in a patient with congenital glaucoma.

A 27-year-old female presented with a sudden decrease of vision in the left eye (OS). Ocular history included advanced congenital glaucoma and previous (15 years) bilateral penetrating keratoplasty and cyclophotocoagulation (9 months) in the left eye. The patient had microcystic corneal edema and Descemet's membrane (DM) detachment; imaging confirmed the detachment with no detectable breaks. DM re-attachment was attempted with an intracameral air bubble tamponade. The edema improved 10 days postoperatively and the graft became clear. Late-onset DM detachment following keratoplasty can occur in patients with congenital glaucoma with no history of recent trauma or eye rubbing. The exact mechanism is unknown, but transscleral cyclophotocoagulation may have a causative role. Timely treatment with air injection results in successful anatomic outcomes.

Collagen fibrils and proteoglycans of peripheral and central stroma of the keratoconus cornea - Ultrastructure and 3D transmission electron tomography.

Keratoconus (KC) is a progressive corneal disorder in which vision gradually deteriorates as a result of continuous conical protrusion and the consequent altered corneal curvature. While the majority of the literature focus on assessing the center of this diseased cornea, there is growing evidence of peripheral involvement in the disease process. Thus, we investigated the organization of collagen fibrils (CFs) and proteoglycans (PGs) in the periphery and center of KC corneal stroma. Three-dimensional transmission electron tomography on four KC corneas showed the degeneration of microfibrils within the CFs and disturbance in the attachment of the PGs. Within the KC corneas, the mean CF diameter of the central-anterior stroma was significantly (p ˂ 0.001) larger than the peripheral-anterior stroma. The interfibrillar distance of CF was significantly (p ˂ 0.001) smaller in the central stroma than in the peripheral stroma. PGs area and the density in the central KC stroma were larger than those in the peripheral stroma. Results of the current study revealed that in the pre- Descemet's membrane stroma of the periphery, the degenerated CFs and PGs constitute biomechanically weak lamellae which are prone to disorganization and this suggests that the peripheral stroma plays an important role in the pathogenicity of the KC cornea.

Clinical and Ultrastructural Studies of Gelatinous Drop-Like Corneal Dystrophy (GDLD) of a Patient with TACSTD2 Gene Mutation.

PURPOSE: To describe clinical, molecular genetics, histopathologic and ultrastructural findings of gelatinous drop-like corneal dystrophy (GDLD) (OMIM #204870) in a Sudanese patient. METHOD: An ocular examination revealed the onset of GDLD in a Sudanese patient (50 years old) at King Khalid Specialist Hospital, Riyadh. The 333 sequence variants in 13 GDLD genes of a DNA sample were screened by Asper Ophthalmics Ltd. It was further confirmed by sequencing. The patient had undergone a penetrating keratoplasty in the right eye. The corneal tissue was processed for histopathology and ultrastructural studies. RESULTS: Slit-lamp observation showed grayish-white multiple superficial corneal nodules of various sizes in the left and right eye. Both corneas became clear after the surgery. The GDLD deposits in the subepithelial region and in the anterior stroma were confirmed by PAS staining and their apple-green birefringence under polarized light. Ultrastructurally, the amyloid fibrils were very thin and grouped in whorl-like structures, which caused splits between and within the stromal lamellae. Collagen fibrils (CFs) and keratocytes had degenerated. A homozygous c.355T > A mutation in exon 1 of the TACSTD2 (M1S1) gene was detected, and alteration of the amino acid (p.Cysl19Ser in NCBI entry NP_002344.2) was observed. CONCLUSION: In our patient with GDLD, a "c.355T > A" mutation in exon 1 of TACSTD2 was detected and believed to be responsible for the alteration of the amino acid leading to the formation of the amyloid deposits. The deposits caused the ultrastructural degeneration of epithelium, Bowman's layer, stroma, and keratocytes of the GDLD cornea.

A new technique to mark the donor and host corneas in keratoplasty.

A new technique is described to easily and accurately mark the donor and the host cornea in keratoplasty using simple, readily available instruments and utilizing a simple mathematical equation. This technique will allow for even distribution of the donor tissue in the recipient bed.

Ultrastructural study of peripheral and central stroma of keratoconus cornea.

PURPOSE: Assess the lamellar organisation of the peripheral and central stroma of the keratoconus (KC) and normal cornea. METHODS: Five normal and three KC corneas were fixed in 2.5% glutaraldehyde and processed for electron microscopy. The ultrathin sections were observed under JEOL 1400 TEM, and digital images were taken with a bottom-mounted 11-megapixel Quamisa camera, using the iTEM software. Measurements of the lamellae were carried out using the iTEM software. Statistical analysis was performed using the SPSS software. RESULTS: The lamellar organisation at the centre and periphery of the KC cornea was disrupted by the presence of multiple undulations, which were more aggressive at the posterior stroma. Among the KC cornea, the mean lamellar thickness of the peripheral middle (1030.32±86.25 nm) and posterior (615.68±30.94 nm) stroma was also significantly (p<0.05) thinner than their corresponding areas of the central KC cornea (1151.1±48 nm; 783.57±31.10 nm). At the periphery of KC cornea, just above the Descemet's membrane (DM), small undulations appeared to emerge out from the DM. Furthermore, the anterior stroma of the peripheral cornea contained several lamellar sutures. The mean lamellar thickness of the peripheral and central KC cornea was significantly (p<0.0001) thinner than the corresponding areas of the normal cornea. CONCLUSION: The present study reveals the involvement of lamellae in the peripheral stroma in the pathogenicity of the KC cornea. The emergence of small undulations in the DM suggests that the formation of undulation might be starting from the DM.

Multifocal Choroiditis with Retinal Vasculitis, Optic Neuropathy, and Keratoconus in a Young Saudi Male.

The purpose of this study is to describe an association of unilateral multifocal choroiditis (MFC), retinal vasculitis, optic neuropathy, and bilateral keratoconus in a young Saudi male. A 27-year-old male patient with stable bilateral keratoconus presented with a painless vision loss in his left eye. Ophthalmic examinations revealed multiple foci of idiopathic chorioretinitis, retinal vasculitis, and mild optic disc leakage on fluorescein angiography, all of which resolved on systemic therapy with mycophenolate mofetil and prednisone after 3 months. Systemic medication was stopped after 8 months. One year after presentation, patient's visual acuity has improved and remained stable. Systemic immunomodulatory therapy can be effective in managing and leading to resolution of MFC, retinal vasculitis, and optic disc leak in young patients.

Streptococcus agalactiae Endophthalmitis in Boston Keratoprosthesis in a Patient with Steven-Johnson Syndrome.

A 25-year-old Syrian male with a previous episode of Stevens-Johnson syndrome with bilateral corneal cicatrization previously underwent surgery for Type 1 Boston Keratoprosthesis (K-Pro). Sixteen months after the K-Pro surgery, the patient presented with decreased vision to hand motion and microbial keratitis of the graft around the K-Pro with purulent discharge. Corneal scrapings were nonrevealing. B-scan in 3 days showed increased debris in the vitreous cavity and thickened retinochoroidal layer. Intravitreal tap and injections of vancomycin and ceftazidime were performed. The vitreous culture revealed ß-hemolytic Streptococcus agalactiae; fungal cultures were negative. Repeat B-scan 3 days later demonstrated decreased vitreous opacity, and the patient felt more comfortable and was without pain. His visual acuity improved to 20/70, ocular findings have been stable for 9 months, and the patient continues to be monitored.

Ultrastructural and three-dimensional study of post-LASIK ectasia cornea.

INTRODUCTION: Post-laser in situ keratomileusis (LASIK) corneal ectasia is a serious late postoperative complication. Here, we report the ultrastructural features of the post-LASIK cornea of two patients. METHODS: Two normal corneas (age 24 and 37 years old) and two post-LASIK ectaic corneas from two patients (A and B) were studied. The "patient A" (age 27 years) underwent penetrating keratoplasty and "patient B" (age 31 years) underwent deep-anterior lamellar keratoplasty. The excised corneas were processed for light and electron microscopy. A total of 120 images for three-dimensional (3D) reconstruction were taken by using the software "Recorder" and using a bottom mounted camera "Quemesa" attached to a JOEL 1400 transmission electron microscope. The 3D images were constructed using "Visual Kai" software. RESULTS: In the post-LASIK cornea, the hemidesmosomes, the basement membrane, and Bowman"s layer were abnormal. The stromal lamellae were thin and disorganized. The collagen fibrils (CFs) diameter and interfibrillar spacing had decreased. Aggregated microfibrils were present in the Bowman's layer and all parts of the stroma. A large number of microfilaments were present at the detachment end of the flap and residual stroma. The 3D images showed the presence of collagen microfibrils and proteoglycans (PGs) within the CF of the normal and post-LASIK cornea. The collagen microfibrils and PGs within the CFs had degenerated in the post-LASIK cornea. CONCLUSION: Collagen microfibrils and PGs within the CFs were degenerated, leading to the degeneration of CFs, followed by the disorganization of lamellae in post-LASIK cornea. The CFs diameter and interfibrillar spacing decreased.

Ultrastructural features of corneas with pellucid marginal degeneration.

PURPOSE: Pellucid marginal degeneration (PMD) of the cornea is a rare ectatic disorder which typically affects the inferior or superior peripheral cornea in a crescentic fashion. We report histological and ultrastructural features of three PMD corneas. METHODS: The following three patients were diagnosed with PMD corneas: (A) one 41-year-old male, (B) one 56-year-old female, and (C) one 31-year-old male. The patients underwent keratoplasty and the excised corneas were processed for light and electron microscopy to study the ultrastructural features. RESULTS: Degenerated corneas were observed in the region adjacent to the limbus. In the degenerated region of the cornea, the Bowman's layer had been replaced by collagenous pannus and the anterior stroma contained degenerated collagen fibrils (CFs) with very large proteoglycans (462±420 nm(2)). The lamellae were fused and keratocytes appeared like fibroblast. The prelimbal region of the PMD cornea had a degenerated Bowman's layer and thin undulating lamellae in the stroma. The CFs of the Bowman's layer and the stroma were replaced by very fine microfilaments. The mean of the minimum CF diameter was 19±3 nm in London Rsin White-embedded tissue. CONCLUSIONS: Our observations of the disorganization and degeneration of CFs suggest that PMD could be related to a disorder in the synthesis of CF. This disorder was more severe in the cornea adjacent to the limbus compared to the cornea further away from the limbus.

Regression of aggressive corneal vascularization after photodynamic therapy, subconjunctival Avastin injections and topical cyclosporin-A 1% drops: A case report.

We describe a case of significant regression of aggressive, deep and superficial corneal vascularization using photodynamic therapy (PDT) with verteporfin, repeated subconjunctival injections of Avastin®, plus topical cyclosporin-A 1% drops. The area of the corneal vascularization was treated with PDT with verteporfin. The subconjunctival space - next to the area of vascularization - was injected with Avastin® (1.25 mg/0.05 ml), immediately after PDT, and then for two more times during the follow-up period. The patient was kept on topical cyclosporin and prednisolone acetate. The outcome was evaluated clinically and photographically for 13 months. Corneal vascularization regressed significantly. No adverse effects were observed, neither locally or systemically. PDT with verteporfin, repeated subconjunctival injections of Avastin®, and topical cyclosporin-A drops appear to be safe and effective in treating aggressive corneal vascularization.

Bilateral infectious keratitis after implantation of intrastromal corneal ring segments.

PURPOSE: To report the development of bilateral infectious keratitis after implantation of intrastromal corneal ring segments (ICRSs). DESIGN: Retrospective case report. PARTICIPANTS: A 20-year-old woman presented with photophobia, decreased vision, and pain 11 days after uncomplicated implantation of ICRSs for keratoconus in both eyes. Bilateral corneal stromal infiltrates were noted at the site of ICRSs implantation. INTERVENTION: The patient was started on frequent topical fortified antibiotics in both eyes. Despite aggressive medical management, stromal infiltrates progressed, necessitating removal of ICRSs from both corneas to control infectious keratitis and melting of cornea. METHODS: Retrospective case report of a 20-year-old woman who developed bilateral severe infectious keratitis 11 days after uncomplicated implantation of ICRSs for keratoconus. RESULTS: Cultures obtained at the time of initial presentation yielded Streptococcus viridans. Patient responded well to the treatment and was left with stromal scars in both corneas. CONCLUSIONS: Although rare, simultaneous implantation of ICRSs may carry a risk of severe bilateral infectious keratitis. Early recognition of infection, aggressive treatment with antibiotics, and, in some cases, removal of ICRSs may be necessary to prevent serious sight-threatening complication of this refractive procedure.