Prevalence of Keratoconus Based on Scheimpflug Imaging: The Raine Study.

PURPOSE: To describe the prevalence and systemic associations of keratoconus in young adults in Perth, Western Australia. DESIGN: Cross-sectional study. PARTICIPANTS: One thousand two hundred fifty-nine participants 20 years of age. METHODS: The Raine Study is a multigenerational, longitudinal cohort study based in Perth, Western Australia. This study represents a cross-sectional analysis of the birth cohort on returning for a 20-year follow-up. Participants underwent a detailed ophthalmic examination, including visual acuity assessment and Scheimpflug imaging using the Pentacam (Oculus, Wetzlar, Germany), and completed a health questionnaire. Keratoconus was defined as a Belin/Ambrόsio enhanced ectasia display score of 2.6 or more in either eye based on Pentacam imaging. MAIN OUTCOME MEASURES: Prevalence of keratoconus in this cohort. RESULTS: Of the 1259 participants, 50.8% were women and 85.7% were White. Fifteen participants had keratoconus in at least 1 eye, giving a prevalence of 1.2% (95% confidence interval, 0.7%-1.9%), or 1 in 84. A significant difference was found in best-corrected visual acuity (0.01 logarithm of the minimum angle of resolution vs. -0.05 logarithm of the minimum angle of resolution; P = 0.007), cylinder (1.25 diopters [D] vs. 0.25 D cylinder; P < 0.001) and spherical equivalent (-1.42 D vs. -0.50 D sphere; P = 0.02) on objective refraction, mean keratometry of the steep meridian (45.19 D vs. 43.76 D; P < 0.001), and mean corneal thickness at the thinnest point (475 µm vs. 536 µm; P < 0.001) between those with and without keratoconus. Keratoconus was associated with regular cigarette smoking (38.5% vs. 14.6%; P = 0.04), but showed no association with gender, race, body mass index, use of spectacles or contact lenses, history of allergic eye disease, or pregnancy. CONCLUSIONS: The prevalence of keratoconus in this Australian population-based study of 20-year-old adults was 1.2% (95% confidence interval, 0.7%-1.9%), or 1 in 84, which is one of the highest reported in the world. This has important implications for screening individuals at a younger age so that treatment can be initiated before disease progression.

Techniques of noncircular corneal transplantation.

PURPOSE OF REVIEW: The management of peripheral corneal diseases, including Mooren's ulcer, Terrien's marginal degeneration, peripheral ulcerative keratitis and pellucid marginal degeneration is challenging. Circular grafts must either be very large, resulting in the excision of healthy tissue, or eccentric, leading to high levels of astigmatism. This review summarizes the range of noncircular keratoplasty procedures available to surgeons, in addition to their indications, and surgical techniques. RECENT FINDINGS: Noncircular grafts have been demonstrated to be useful in the management of peripheral corneal diseases. They are effective at providing tectonic support and also facilitate visual rehabilitation. Specifically, they produce favourable postoperative visual and astigmatic outcomes. The evidence relating to these procedures is largely limited to case reports and case series, with no large-scale studies available. SUMMARY: Noncircular keratoplasty procedures are useful in the management of peripheral corneal diseases, which is typically difficult. There is a need for larger studies to investigate the relative advantages and disadvantages of these procedures and further characterize their outcomes.

Gram-negative endophthalmitis: A prospective study examining the microbiology, clinical associations and visual outcomes following infection.

IMPORTANCE: This is the largest Gram-negative endophthalmitis specific series and provides important evidence to guide management. BACKGROUND: Endophthalmitis is a sight-threatening emergency. Gram-negative infections are associated with poorer visual outcomes; however, there is limited literature pertaining to this uncommon condition. DESIGN: Prospective case series. PARTICIPANTS: All patients presenting with endophthalmitis to a tertiary institution over a 20-year period. METHODS: Data were collected prospectively and entered into a registry. Patients with microbiological evidence of Gram-negative infection were included in the analysis. MAIN OUTCOMES MEASURES: Final visual acuity (VA), precipitating events, causative organisms, antibiotic sensitivity profiles and risk factors for poor visual outcomes were reported. RESULTS: One hundred Gram-negative organisms were isolated in 97 eyes. Final VA was worse than 6/60 in 65 (67.0%) eyes at follow-up and 29 (29.9%) eyes were eviscerated or enucleated. Microbial keratitis (26.8%, n = 26) and Pseudomonas aeruginosa (34.0%, n = 34) were the most common precipitating event and causative organism, respectively. Eight (8.0%) isolates were third-generation cephalosporin resistant; of which, 7 (88.0%) were sensitive to ciprofloxacin. Preceding microbial keratitis (OR = 13.16, P = .015) or P. aeruginosa infections (OR = 3.40, P = .045) were strongly associated with poorer visual outcomes (worse than 6/60). CONCLUSIONS AND RELEVANCE: Visual outcomes following Gram-negative endophthalmitis are extremely poor, with almost 30% of patients being eviscerated or enucleated. A majority of ceftazidime resistant organisms are sensitive to ciprofloxacin, providing evidence to support the empirical use of quinolones. Clinicians should be mindful that infections secondary to P. aeruginosa or microbial keratitis carry a particularly poor prognosis.

Hybrid Neurofibroma/Schwannoma of the Orbit.

A 68-year-old female presented for assessment of a space occupying lesion of her right orbit, demonstrated on MRI. An upper lid crease anterior orbitotomy was performed and the lesion excised completely. Postoperatively, she had reduced sensation in the distribution of the supraorbital nerve. Histopathologic examination of the excised lesion revealed a hybrid neurofibroma/schwannoma. This represents the fourth reported case of such a lesion arising within the orbit.

Conjunctival ultraviolet autofluorescence area decreases with age and sunglasses use.

BACKGROUND: Conjunctival ultraviolet autofluorescence (CUVAF) is a method of detecting conjunctival damage related to ultraviolet radiation exposure. In cross-sectional studies, CUVAF area is positively associated with self-reported time spent outdoors and pterygium and negatively associated with myopia; however, longitudinal studies are scarce. AIMS: To use a novel deep learning-based tool to assess 8-year change in CUVAF area in young adults, investigate factors associated with this change and identify the number of new onset pterygia. METHODS: A deep learning-based CUVAF tool was developed to measure CUVAF area. CUVAF area and pterygium status were assessed at three study visits: baseline (participants were approximately 20 years old) and at 7-year and 8-year follow-ups. Participants self-reported sun protection behaviours and ocular history. RESULTS: CUVAF data were available for 1497 participants from at least one study visit; 633 (43%) participants had complete CUVAF data. Mean CUVAF areas at baseline and the 7-year and 8-year follow-ups were 48.4, 39.3 and 37.7 mm2, respectively. There was a decrease in mean CUVAF area over time (change in total CUVAF area=-0.96 mm2 per year (95% CI: -1.07 to -0.86)). For participants who wore sunglasses ≥1/2 of the time, CUVAF area decreased by an additional -0.42 mm2 per year (95% CI: -0.72 to -0.12) on average. Fourteen (1.5%) participants developed a pterygium. CONCLUSIONS: In this young adult cohort, CUVAF area declined over an 8-year period. Wearing sunglasses was associated with a faster reduction in CUVAF area. Deep learning-based models can assist in accurate and efficient measurement of CUVAF area.

Laser-assisted corneal transplantation surgery.

Corneal transplant surgeries have a broad range of indications with outcomes largely dependent on surgeon experience. Traditional manual techniques have certain limitations pertaining to the preparation of donor tissue and the recipient bed that might affect the predictability of visual outcomes. Use of lasers for keratoplasty procedures not only improves the repeatability and consistency of the technique, but also enables the surgeon to control the thickness and shape of the transplant tissue tailored to the specific condition. Despite the advantages, cost-effectiveness and technical know-how remain the major challenges. We discuss the various techniques of laser-assisted keratoplasties with respect to their methods, precision, and efficacy in various corneal indications.

Ptosis, ophthalmoplegia and corneal endothelial disease - ocular manifestations of mitochondrial disease.

PURPOSE: To describe two patients with bilateral ptosis, ophthalmoplegia, cataracts and corneal endothelial disease requiring corneal transplantation. OBSERVATIONS: Histopathological analysis of muscle biopsy samples from both patients identified features consistent with a mitochondrial cytopathy. A single multigenic mitochondrial deoxyribonucleic acid (DNA) deletion was detected in the first patient. Pathogenic mutations in the POLG gene which codes for mitochondrial DNA polymerase, tasked with replicating the mitochondrial genome were identified in the second patient. CONCLUSION: The collection of clinical features present in both cases described can be explained by a diagnosis of mitochondrial disease. IMPORTANCE: Corneal endothelial disease, in addition to ptosis, ophthalmoplegia, cataract, pigmentary retinopathy and optic atrophy should be recognised as a feature of mitochondrial disease.

Has the Sun Protection Campaign in Australia Reduced the Need for Pterygium Surgery Nationally?

BACKGROUND: The Slip! Slop! Slap! Sunsmart safety campaign was an Australian initiative implemented in the 1980s. To assess this campaign's effect on pterygium, we examined the rate of pterygium surgery across Australia and described the prevalence and associations of pterygium in Perth, Australia's sunniest capital city. METHODS: The rate of pterygium surgery was examined using Australian Medicare data. A cross-sectional analysis of the Generation 1 (Gen1) cohort of the Raine Study was performed to investigate the prevalence of pterygium in Perth. We investigated the association between pterygium and conjunctival ultraviolet autofluorescence (CUVAF) area, an objective biomarker of sun exposure, and demographics and health variables derived from a detailed questionnaire. RESULTS: Between 1994 and 2017, the rate of Medicare funded pterygium surgery in Western Australia fell 11%, well below the national average decline of 47%. Of the 1049 Gen1 Raine Study participants, 994 (571 females; mean age 56.7 years, range = 40.9-81.7) were included in the analysis. The lifetime prevalence of pterygium was 8.4% (n = 83). A higher prevalence of pterygium was associated with outdoor occupation (p-trend = 0.007), male sex (p-trend 0.01) and increasing CUVAF area (p-value <0.001). CONCLUSIONS: The effect of Australia's Slip! Slop! Slap! Sunsmart safety campaign on pterygium been mixed. Since 1994, the rate of private pterygium surgery has declined significantly in all Australian states except Western Australia. Perth, Western Australia, has the highest pterygium prevalence of any mainland-Australian cohort. Higher CUVAF area, male sex, and outdoor occupation were associated with an increased risk of pterygium.

Management of corneal perforations: An update.

Corneal perforation is a potentially devastating complication that can result from numerous conditions that precipitate corneal melting. It is associated with significant morbidity and prompt intervention is necessary to prevent further complications. Causes include microbial keratitis, ocular surface disease, and autoimmune disorders and trauma. Various management options have been described in the literature to facilitate visual rehabilitation. This rview discusses the treatment options that range from temporising measures such as corneal gluing through to corneal transplantation, with decision making guided by the location, size, and underlying aetiology of the perforation.

Single Muscle Transposition in the Management of Monocular Elevation Deficiency.

Monocular elevation deficiency is characterized by the inability to elevate one eye in abduction, adduction, and primary gaze. To date, various operations, including Knapp's procedure, have been used in the management of hypotropia associated with this condition. However, single muscle transposition has only recently been described as a feasible alternative, offering a number of advantages over other techniques. In particular, it reduces the risk of anterior segment ischemia and allows for an inferior rectus recession to occur simultaneously as is often required, thus avoiding the need for staged operations. It also facilitates a wider range of management options to correct for associated horizontal deviation. We present a case detailing the use of single muscle transposition in the management of monocular elevation deficiency and in doing so confirm the utility of this novel technique.

Impact of corneal refractive surgery on the precorneal tear film.

Corneal refractive surgeries are one of the commonly performed procedures for correction of refractive errors. Tear film abnormality is the most common postoperative complication of corneal refractive surgeries. Consequently, these procedures represent a clinically significant cause of dry eye disease. The mechanisms which lead to dry eye disease include corneal sensory nerve dysfunction, ocular surface desiccation, glandular apoptosis and ocular surface inflammation. Although transient tear film abnormalities occur in almost all patients following surgery, patients with pre-existing dry eye symptoms or dry eye disease are at significant risk of developing more severe or long-term ocular surface disease. As such, careful patient selection and preoperative evaluation is essential to ensuring successful surgical outcomes. This is particularly important with LASIK which has the strongest association with dry eye disease. Appropriate surface lubrication and anti-inflammatory therapy remains the cornerstone treatment. Timely and effective management is important to facilitate visual rehabilitation and reduce the risk of secondary complications. In this review we describe the causes, pathophysiology, risk factors, manifestations, and management of tear film dysfunction and dry eye disease following corneal refractive surgery.

Postoperative detection of unusual pathology in donor corneal tissue.

We present a series of three patients with previously undetected corneal pathology in grafted corneal tissue following keratoplasty for keratoconus. Postoperatively, a faint layer of anterior stromal haze involving the graft was observed in each patient upon slit lamp examination. Anterior segment optical coherence tomography (AS-OCT) confirmed the presence of anterior stromal scarring across the transplanted cornea. However, the ocular and systemic medical histories of the donors were unremarkable. As the suboptimal donor corneal tissue may escape the standard screening protocols, eye banks should consider adding AS-OCT imaging for screening donor corneal tissue before transplantation.

Comparative Evaluation Of Clinical Characteristics And Visual Outcomes Of Traumatic And Non-Traumatic Graft Dehiscence Following Corneal Transplantation Surgery.

PURPOSE: To compare patient demographics, clinical associations and visual outcomes between traumatic and non-traumatic wound dehiscence, following corneal transplantation. METHODS: Retrospective review of all patients presenting with post-keratoplasty wound dehiscence to the Royal Victorian Eye and Ear Hospital between January 2005 and December 2017. Patients with wound dehiscence following keratoplasty of any cause were included. RESULTS: Of 71 eyes from 71 patients included, 60 (85%) were penetrating keratoplasty patients. The mean age was 56.4 years (SD=22.7, range 17.6-97) and 62% (n = 44) of patients were male. There were 28 (39%) cases of traumatic dehiscence and 43 (61%) cases of non-traumatic dehiscence. The median time interval from keratoplasty to dehiscence was significantly less in non-traumatic patients than traumatic patients (0.2 years, IQR 0.1-2.0 vs 2.3 years, IQR 0.3-14.8, p=0.01). There was no significant difference in best-corrected visual acuity at 6 months between traumatic and non-traumatic dehiscence (6/60 vs 6/36, p=0.62), suture technique (continuous vs interrupted, p=0.12), or graft type (penetrating keratoplasty vs deep anterior lamellar keratoplasty) after adjusting for keratoconus (p=0.41). CONCLUSION: Post-keratoplasty wound dehiscence is a serious complication and can cause significant loss of vision. While the risk of dehiscence is lifelong, the first 3 years post-keratoplasty carry the highest risk, with non-traumatic dehiscence tending to occur earlier than traumatic dehiscence.

Choroidal Melanoma Metastatic to the Contralateral Medial Rectus After Orbital Exenteration

A 78-year-old Caucasian woman presented with pain in her right and only eye that was worse on abduction. Her history was significant for a choroidal melanoma affecting her left eye for which she underwent an orbital exenteration 12 years previously. Computed tomography and magnetic resonance imaging of the right orbit identified a mass lesion affecting the medial rectus, suspicious for metastatic melanoma. A histopathological diagnosis of metastatic melanoma was subsequently made following biopsy of the right medial rectus.

Estimation of heritability and familial correlation in myopia is not affected by past sun exposure.

Purpose: To consider the effect of including past sun exposure in estimating heritability and familial correlation of myopia-related traits.Methods: We calculate familial correlation and heritability of anterior chamber depth (ACD), axial length (AL), corneal curvature (CC), and spherical equivalent (SphE), with or without past sun exposure as a covariate, in a large number of unrelated nuclear families from the Raine Study (parents: Gen1, offspring: Gen2) residing in Perth, Australia, a city with a high amount of daily sunlight. Past sun exposure was objectively measured using conjunctival ultraviolet autofluorescence (CUVAF) photography.Results: When sun exposure was not included in the analysis, both familial correlation (correlation±SE; ACD: 0.308 ± 0.065, AL: 0.374 ± 0.061, CC: 0.436 ± 0.063, SphE: 0.281 ± 0.070) and heritability (ACD: 0.606 ± 0.104, AL: 0.623 ± 0.098, CC: 0.793 ± 0.079, SphE: 0.591 ± 0.106) were significant for all traits (all P < .001). However, there was no significant change in both familial correlation and heritability estimates when sun exposure was included as an additional covariate.Conclusions: Past sun exposure does not affect the estimation of the additive genetic component in myopia-related traits.