1 year posterior corneal changes after Bowman Layer Transplant for keratoconus.

INTRODUCTION: To report the posterior corneal changes after Bowman Layer Transplant for keratoconus in a tertiary hospital in the UK. METHODS: 5 eyes of 5 patients receiving Bowman Layer Transplant for advanced keratoconus in Royal Gwent Hospital (Newport, UK) were included. Pre and postoperative posterior corneal astigmatism, posterior Kmean, and back surface elevation were analysed. RESULTS: No significant changes were seen in the posterior corneal astigmatism, posterior Kmean, or back surface elevation between the pre- and postoperative period. CONCLUSION: This results would support the idea that the corneal changes seen after Bowman Layer Transplant are mainly in the anterior corneal surface.

Tectonic Descemet Stripping Endothelial Keratoplasty for the Management of Corneal Perforation: A Case Series.

PURPOSE: Corneal perforations pose a considerable challenge for ophthalmic surgeons. The aim remains restoring the anatomical integrity of eye while attempting to preserve as much visual function as possible. To our knowledge, we report the first case series of 4 successful tectonic Descemet stripping endothelial keratoplasty (DSEK) grafts completed for acute corneal perforation. In all cases, restoration of globe integrity was achieved. In cases where visual potential remained, deep anterior lamellar keratoplasty over DSEK was offered. METHODS: Four patients presenting to Royal Gwent Hospital (Newport, Wales) with corneal perforation were included. Etiological origins included exposure keratopathy, corneal hydrops secondary to pellucid marginal degeneration with fistulization-associated aqueous leak, and herpetic keratitis. Patients were treated with initial temporary therapies, including glue patch, the use of bandage contact lenses, amniotic membrane transplant, and antibiotic cover, depending on the size and location of the perforation. Subsequent DSEK was subsequently performed under local anesthesia. RESULTS: All patients had successful tectonic grafts (3 DSEKs and 1 hemi-DSEK) up to 4 months postoperatively. In the case involving a hemi-DSEK, the patient underwent 2 refloating attempts of the graft before anchoring suture placement because of repeated graft detachment. Successful graft placement and tectonic globe restoration was confirmed by anterior segment imaging. CONCLUSIONS: Tectonic DSEK provides corneal surgeons with a new modality of treating corneal perforations. It provides clinicians an additional tool in their armamentarium in complex cases where anterior lamellar or penetrating keratoplasty may be contraindicated or deemed high risk of complications.

Personal hygiene risk factors for contact lens-related microbial keratitis.

OBJECTIVE: Microbial keratitis is a sight-threatening complication of contact lens wear, which affects thousands of patients and causes a significant burden on healthcare services. This study aims to identify compliance with contact lens care recommendations and identify personal hygiene risk factors in patients who develop contact lens-related microbial keratitis. METHODS AND ANALYSIS: A case-control study was conducted at the University Hospital Southampton Eye Casualty from October to December 2015. Two participant groups were recruited: cases were contact lens wearers presenting with microbial keratitis and controls were contact lens wearers without infection. Participants underwent face-to-face interviews to identify lens wear practices, including lens type, hours of wear, personal hygiene and sleeping and showering in lenses. Univariate and multivariate regression models were used to compare groups. RESULTS: 37 cases and 41 controls were identified. Showering in contact lenses was identified as the greatest risk factor (OR, 3.1; 95% CI, 1.2 to 8.5; p=0.03), with showering daily in lenses compared with never, increasing the risk of microbial keratitis by over seven times (OR, 7.1; 95% CI, 2.1 to 24.6; p=0.002). Other risks included sleeping in lenses (OR, 3.1; 95% CI, 1.1 to 8.6; p=0.026), and being aged 25-39 (OR, 6.38; 95% CI, 1.56 to 26.10; p=0.010) and 40-54 (OR, 4.00; 95% CI 0.96 to 16.61; p=0.056). CONCLUSION: The greatest personal hygiene risk factor for contact lens-related microbial keratitis was showering while wearing lenses, with an OR of 3.1, which increased to 7.1 if patients showered daily in lenses. The OR for sleeping in lenses was 3.1, and the most at-risk age group was 25-54.

Modified thin manual Descemet stripping endothelial keratoplasty with air-guided, non-pachymetric donor lenticule dissection: outcomes of graft thickness and complication rate.

AIM: To describe a modified technique of donor lenticule dissection for thin manual Descemet stripping endothelial keratoplasty (TM-DSEK). METHODS: Donor material was soaked in balanced salt solution (BSS) for 30min, before being mounted on an artificial anterior chamber (AAC). Rather than BSS, the AAC was filled with filtered air, resulting in a visible reflection at the corneal endothelium-air interface. This reflection served as a landmark for the depth of the dissection, facilitating the creation of a thin lenticule with low risk of perforation. Dissection was commenced at a standardized depth of 500 microns, with no initial pachymetry necessary. Totally 29 donor corneas were dissected by a novice TM-DSEK surgeon. Dissection time, central graft thickness at 2mo and complications were analysed. RESULTS: Results were similar to other endothelial keratoplasty techniques, despite the cases being performed by a novice DSEK surgeon. Mean dissection time was 7min (range 6-10). One graft perforation occurred (3.45%), but the air tamponaded the break and enabled dissection to be restarted and completed from a different location. Mean central graft thickness after at least two months follow-up was 106 microns (range 25-170). CONCLUSION: A problem with manual DSEK is the risk of graft perforation by attempting to dissect too thin a lenticule, or creating a thick graft due to fear of perforating. This modified air-guided technique addresses this problem, and is recommended for surgeons either embarking on the learning curve, or who wish to achieve more consistently thin grafts while reducing perforation rates.

In vivo quantification of bacterial keratitis with optical coherence tomography.

PURPOSE: To quantify the human corneal inflammatory response in treated bacterial keratitis with long-wavelength anterior segment optical coherence tomography (AS-OCT). METHODS: Patients with clinically suspected bacterial keratitis were recruited from the corneal service at Southampton Eye Unit, UK. Patients underwent AS-OCT and slit-lamp examination on presentation (day 0) and days 3, 7, and 14 of treatment. Corneal thickness (CT) in the infiltrated area, infiltrate thickness (IT), and infiltrate width (IW) were measured on high-resolution AS-OCT scans. Mean values for each day and rates of change for each interval were calculated and compared (one-way ANOVA, paired t-test). RESULTS: Twenty-six eyes of 26 patients were recruited. Mean CT and IT on presentation were 905 µm and 388 µm, respectively. On days 3, 7, and 14, CT and IT decreased to 753 µm and 320 µm (P < 0.01), 678 µm and 296 µm (P < 0.01), and 584 µm and 207 µm (P < 0.01), respectively. Mean IW, 1498 µm on presentation, did not change during treatment (P > 0.30). Mean daily rate of CT reduction was faster in the early (days 0-3) compared to late (days 7-14) phase (4.49% vs. 1.33%, P = 0.006). Mean daily rate of IT reduction was no different in early, middle, and late phases (5.41% vs. 1.19% vs. 3.38%, P > 0.01). In the late phase, IT decreased faster than CT (3.38% vs. 1.33%, P = 0.003). CONCLUSIONS: CT and IT decreased significantly by day 3 in resolving bacterial keratitis. The rapid early phase reduction in IT and CT was followed by rapid late phase IT reduction. This study demonstrates that serial AS-OCT examination can be used to monitor in vivo the clinical course of inflammatory disease.

Prognostic factors that determine visual outcome following cataract surgery complicated by vitreous loss.

PURPOSE: To identify prognostic factors that determine visual outcome following phacoemulsification cataract surgery complicated by vitreous loss. METHODS: A retrospective cohort study. All cases of vitreous loss during phacoemulsification surgery at a university hospital, between June 2000 and December 2005, were identified from the hospital computer database. By reviewing the medical notes, preoperative, intraoperative, and postoperative data were collected. Outcome of interest was presence of poor visual outcome (best-corrected visual acuity [BCVA] <6/12). Chi-square and Mann-Whitney U tests were used to compare groups of poor and good visual outcome. RESULTS: A total of 230 consecutive cases (eyes) were identified; medical notes were available for 228. Mean patient age was 78.4 years (SD 11); median follow-up 13.4 weeks (range 1-203). In multivariable logistic regression analysis poor visual outcome was independently associated with poor preoperative vision (BCVA <6/12) (OR 3.78, 95% CI 1.76-8.11), age-related macular degeneration (OR 3.04, 95% CI 1.16-8.00), cystoid macular edema (OR 3.85, 95% CI 1.29-11.51), and secondary pars plana vitrectomy (PPV) for nuclear fragment loss (OR 4.42, 95% CI 1.03-19.02). Primary PPV for nuclear fragment loss, age >70, ocular comorbidity, axial length, vitreous loss during irrigation/aspiration, or lens implantation, anterior chamber lens, and secondary lens implantation were not significant associations (p>or= 0.05). In 33 (14.5%) eyes BCVA was reduced by at least one Snellen line compared to before surgery. CONCLUSIONS: Poor visual outcome was associated with poor preoperative vision, age-related macular degeneration, cystoid macular edema, and secondary PPV following nuclear fragment loss. Primary PPV for nuclear fragment loss was not a significant association.

Late intraocular pressure rise following intravitreal triamcinolone injection.

Most ophthalmologists are aware of the risk of elevated intraocular pressure developing 1 or 2 months after an intravitreal injection of triamcinolone. However, the two cases reported here demonstrate that such a rise can occur significantly later than this. All patients who have had intravitreal steroid injection should therefore have prolonged intraocular pressure monitoring.

Recent advances in ophthalmic anterior segment imaging: a new era for ophthalmic diagnosis?

Anterior segment imaging is a rapidly advancing field of ophthalmology. New imaging modalities, such as rotating Scheimpflug imaging (Pentacam-Scheimpflug) and anterior segment optical coherence tomography (Visante OCT and Slit-Lamp OCT), have recently become commercially available. These new modalities supplement the more established imaging devices of Orbscan scanning slit topography and ultrasound biomicroscopy (UBM). All devices promise quantitative information and qualitative imaging of the cornea and anterior chamber. They provide a quantitative angle estimation by calculating the angle between the iris surface and the posterior corneal surface. Direct angle visualisation is possible with the OCT devices and UBM; they provide images of the scleral spur, ciliary body, ciliary sulcus and even canal of Schlemm in some eyes. Pentacam-Scheimpflug can measure net corneal power, a feature particularly useful for cataract patients having undergone previous corneal surgery. Anterior segment OCT can measure corneal flap depth following LASIK and anterior chamber width prior to phakic intraocular lens implantation. The arrival of the new imaging devices may herald the dawn of a new era for ophthalmic diagnosis, particularly in view of the ease and non-contact nature of examination.