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.

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.

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.

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.

Ultrastructure and 3D transmission electron tomography of collagen fibrils and proteoglycans of swollen human corneal stroma

BACKGROUND

The transparency of the cornea is regulated by the unique organization of collagen fibrils (CFs) which is maintained by proteoglycans (PGs). The interlacing of CF lamellae in the anterior stroma provides the biomechanical properties of the cornea.

OBJECTIVE

To investigate the alterations of CFs and PGs in the swollen cornea, with special reference to the anterior stroma by using electron microscopy and 3D ultrastructural tomography.

METHOD

Nine healthy normal scleral corneal rings (age from 40 to 65 years) were hydrated individually in deionised water to induce swelling in the cornea. Three of them were hydrated for 2hr whereas the other three were hydrated for 48hr. The remaining three scleral normal corneal rings were used as a control.The corneas were processed for electron microscopy (EM) to study the CFs and PGs. Ultrathin sections were observed using transmission electron microscopy (JOEL 1400) and digital images of CFs, PGs and lamellae were captured using a bottom mounted Quemesa camera and iTEM Soft Imaging System. The software program 'Composer-x64, version 3.4.2.0' was used to construct individual 3D images from 120 digital images taken from -60 to + 60 degree angles.

RESULTS

The 3D tomography showed the degeneration of microfibrils within the CFs of the swollen cornea. The CF diameter was significantly reduced and the interfibrillar spacing significantly increased in both the 2hr and 48hr hydrated corneas compared to the normal cornea. Within the hydrated corneas, the CF diameter was smaller and the interfibrillar spacing was increased in the middle and posterior stroma compared to the anterior stroma. The PG area in both the 2hr and the 48hr hydrated cornea was reduced in the anterior stroma, whereas it was increased in middle and posterior stroma compared to the normal cornea. The density of the PGs in both the 2hr and the 48hr samples, was reduced compared to the density of PGs in the normal cornea.

CONCLUSION

The CFs, PGs and lamellae had degenerated, caused by swelling. 3D imaging demonstrated that the impairment of the microfibrils and PGs within the CF, is caused by the excessive hydration or swelling in the anterior as well as in the middle and posterior stroma. The lamellae of the anterior stroma which provides the biomechanical strength in the normal cornea, had degenerated in the swollen corneas due to the presence of the damaged CFs and PGs.

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.

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.

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 β-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.

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.

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.

Intraocular lens power calculation after phototherapeutic keratectomy: case report and a new method

To report a case of cataract extraction and intraocular lens (IOL) implantation after phototherapeutic keratectomy (PTK). The IOL power was calculated using the single-K and the double-K SRK/T formula, as well as the Haigis formula after modifying the post PTK corneal power using methods described for corneal power measurements after myopic excimer laser treatment (photorefractive keratectomy (PRK) and LASIK). A new method for IOL power calculation after PTK is introduced.

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.