Retrocorneal fibrous membrane after phacoemulsification in an eye with pseudoexfoliative glaucoma.

OBJECTIVE: To report a case of a retrocorneal fibrous membrane and corneal decompensation following uncomplicated phacoemulsification in an eye with pseudoexfoliative glaucoma. METHOD: Case report and literature review. RESULTS: A monocular 83-year-old female developed corneal decompensation 1 year after uncomplicated cataract extraction via phacoemulsification. She had a history of pseudoexfoliative glaucoma and had undergone 3 rounds of selective laser trabeculoplasty in the same eye 3 years prior. Given the resulting corneal edema, the patient underwent Descemet's membrane endothelial keratoplasty, at which time a retrocorneal fibrous membrane was identified. Peeling of the membrane was surgically challenging and resulted in an intraocular hemorrhage intraoperatively and a small iridodialysis because the membrane had extended over the angle and iris. Postoperatively, the cornea cleared well, and vision improved significantly. However, vision was ultimately limited by macular pathology. Pathologic examination demonstrated Descemet's membrane with an attached fibrocellular membrane. Immunostaining for smooth muscle actin was positive within the membrane compatible with a retrocorneal membrane. We also present a review of the literature on modern causes of retrocorneal fibrous membranes. CONCLUSIONS: Retrocorneal fibrous membranes are encountered most commonly following corneal transplantation and may be surgically challenging to remove. We present the first case of a pathologically proven retrocorneal fibrous membrane following uncomplicated cataract surgery via phacoemulsification and selective laser trabeculoplasty.

Face and Content Validity of an Artificial Eye Model for Secondary Intraocular Lens Fixation via Yamane Technique.

Purpose: To assess the face and content validity of an artificial eye model for secondary intraocular lens (IOL) fixation via the Yamane technique. Methods: Ophthalmologists and residents participated in a 90-minute simulation session on secondary IOL fixation via the Yamane technique. Hands-on practice of this technique was performed on an artificial eye, the Bioniko Okulo BR8. After, all ophthalmologists answered an 18-question survey assessing the face and content validity of the model. Survey responses were recorded on a 5-point double-headed Likert scale, ranging from strongly agree (1)-to-strongly disagree (5) (Figure 1). Results: Twenty-three surveys were completed. Respondents rated the survey with a median response of 1 (strongly agree)-to-3 (neutral). Highest ratings for the model were received for "usefulness for training residents", and "easier to set up and clean-up compared to a cadaver". Lowest ratings were received for realism of the model compared to cadaveric eyes. Statistical analysis revealed no significant difference among identified groups. Ratings for face and content validity were viewed favorably, both with an overall median response of 2.00 (agree). Conclusion: The Bioniko Okulo BR8 shows promise as a valid tool for practicing secondary IOL fixation via the Yamane technique. Considering recent guidelines in competency-based ophthalmology education programs, this model may be a valuable tool over traditional techniques for teaching and improving surgical skill amongst trainees.

Comparison of 3D heads-up display system with conventional surgical microscopy for minimally invasive glaucoma surgery on an artificial eye model.

OBJECTIVE: To survey ophthalmic surgeons' opinions comparing a novel three-dimensional (3D) heads-up display system with a conventional surgical microscopy for minimally invasive glaucoma surgery (MIGS) on an artificial eye model. MATERIALS AND METHODS: Twenty-one ophthalmologists at the 2021 Canadian Ophthalmological Society Annual Meeting in Halifax, Nova Scotia, underwent a 90-minute skills-transfer course on MIGS. Using an artificial eye model (SimulEYE iTrack Model; InsEYE LLC, Westlake Village, Calif.), participants engaged in hands-on practice of MIGS via both a 3D heads-up display system (3D HUDS) (Zeiss Artevo 800; Carl Zeiss Meditec, Jena, Germany) and a conventional surgical microscope. Following completion, participants and instructors answered a 16-question survey comparing the 2 systems (3D HUDS vs conventional surgical microscope). Survey responses were recorded on a 9-point double-headed Likert scale ranging from strongly favour 3D HUDS (1) to strongly favour conventional surgical microscopy (9). Mann-Whitney U nonparametric analysis was used to compare instructor versus participants and experts versus nonexperts. RESULTS: Survey ratings favoured the 3D HUDS over the conventional surgical microscopy, with respondent ratings for all survey questions ranging from a response of 1 (strongly favour 3D HUDS) to 5 (equal). Mann-Whitney U statistical analysis revealed no significant difference between instructor versus participant as well as between expert versus nonexpert. Most ratings for the 3D HUDS were received for ergonomic setup of the surgical modality, depth of field (or) field of view, and usefulness in training residents for MIGS. Equal ratings for the 3D HUDS and conventional surgical microscope were received for system malfunctions and lag during surgery. CONCLUSIONS: The 3D HUDS was favoured over conventional microscopy for the performance of simulated MIGS by ophthalmologists with varying levels of experience. The survey results suggest that the 3D HUDS in an artificial eye model is useful for teaching minimally invasive glaucoma surgery, particularly with the advent of competency-based ophthalmology education programs.

Ocular surface squamous neoplasia in a patient following oral steroids for contralateral necrotising scleritis.

A male patient in his 70s presented with left eye necrotising scleritis. His ocular history was significant for pterygium excision with mitomycin C 3 months prior in the affected eye, open-angle glaucoma, nuclear sclerosis cataract and previous sixth cranial nerve palsy. Scleral culture was negative and blood work was positive for rheumatoid factor and HLA-B27. The patient was treated for necrotising scleritis with oral doxycycline, vitamin C, ranitidine and prednisone with gradual taper over 45 days. Two months after initiating treatment, his necrotising scleritis achieved complete resolution; however, a new-onset ocular surface squamous neoplasia (OSSN) was identified at the temporal limbus of the contralateral eye. He was treated with topical interferon alpha-2b 1 million IU qid and achieved complete resolution after 4 months. The case highlights both the acute precipitation of OSSN following oral steroids and a sight-threatening complication following pterygium excision.

Risk factors associated with severity of dry eye syndrome in ocular graft-versus-host disease.

OBJECTIVE: The aim of this study was to identify risk factors for the development of severe dry eye syndrome (DES) in patients with ocular graft-versus-host disease (oGVHD). DESIGN: Retrospective Chart Review. PARTICIPANTS: Patients undergoing allogeneic hematopoietic stem cell transplantation at the British Columbia Cancer Agency between 2011 and 2013. METHODS: A retrospective chart review of post-transplant patients with oGVHD DES followed at the British Columbia Cancer Agency Bone Marrow Transplant Unit was performed. Patient and donor data were collected. Descriptive and inferential statistics were carried out. Linear, logistic, and ordered logistic regression analyses were carried out. DES severity was graded using the National Institutes of Health criteria. RESULTS: Of the 78 patients studied, 39 (50%) were male. The median age and Schirmer score were 56 years (range 24-71 years) and 14 mm (range 0-25 mm), respectively. A lower Schirmer score (p = 0.0001), severe overall chronic graft-versus-host disease (GVHD) (p < 0.0001), and lung involvement (p = 0.04) were associated with worsening oGVHD DES. Ordered logistic regression analysis revealed characteristics predictive of oGVHD severity. Fourteen patients (17.95%) had severe DES. Compared with those with nonsevere DES, this group was more likely to be male (p = 0.02) and have a lower Schirmer score (p = 0.01), significantly worse overall chronic GVHD (p = 0.002), as well as lung (p = 0.02) and gastrointestinal tract (p = 0.02) involvement. Logistic regression analysis revealed characteristics predictive of severe oGVHD DES. CONCLUSION: This study identified potential risk factors associated with the development of severe DES in patients with oGVHD.

Patient comfort and visual outcomes of mini-scleral contact lenses.

OBJECTIVE: To evaluate short-term visual outcome, patient acceptance, and tolerance of mini-scleral contact lenses (SCLs) in the management of various corneal pathologies. DESIGN: Retrospective case series. PARTICIPANTS: Thirty-two patients (40 eyes) who received mini-SCLs. METHODS: Single-centre retrospective case series, between February 2010 and January 2013, of 32 patients (40 eyes) with various corneal pathologies who were offered either Maxim 5R, Maxim 7, or Maxim 7 × 11 mini-SCLs for nonsurgical optimization of visual correction. Patients were followed up at 1 and 3 months for assessment of best-corrected visual acuity, comfort, length of daily wear, and complications. RESULTS: Thirty-two patients (40 eyes), with a mean age of 41 ± 16 years, opted to receive mini-SCLs. Eighteen patients had previously undergone surgery such as penetrating keratoplasty, deep anterior lamellar keratoplasty, and intraocular lens implantation. The median best-corrected visual acuity improved from 0.3 logMAR (range 0-1.3) before mini-SCLs, to 0.05 logMAR (range 0-1) with mini-SCLs (p < 0.0001). At 1-month follow-up, the median length of wear was 10 hours/day (range 1.5-15). At 3-month follow-up, the median length of wear was 12 hours/day (range 2-15). All eyes were comfortable at initial use of mini-SCLs and 91% were comfortable at 3-month follow-up. CONCLUSION: Mini-SCLs may be a comfortable management option for patients with keratoconus and other corneal pathologies who are unable to achieve adequate visual outcome with traditional spectacles or rigid gas-permeable contact lenses.

Dual-purpose corneal tissue for anterior lamellar keratoplasty and Descemet's membrane endothelial keratoplasty.

OBJECTIVE: To assess the intraoperative issues and surgical outcomes of preparing a single-donor corneal tissue for same-day use in both deep anterior lamellar keratoplasty (DALK) and Descemet's membrane endothelial keratoplasty (DMEK). DESIGN: Consecutive retrospective case series. PARTICIPANTS: Ten eyes of 10 patients who underwent DALK (5 patients) or DMEK (5 patients) surgery using dual-purpose corneal tissue. METHODS: Five dual-purpose corneoscleral rims were used to prepare tissue for 5 DMEK and 5 DALK procedures. The submerged cornea using backgrounds away technique was first used to harvest the 5 DMEK grafts, and the remaining tissue was used for the 5 DALK grafts. Tissue preparation and operative use occurred on the same day. Tissue preparation challenges, intraoperative complications, and visual recovery were assessed. RESULTS: There were no difficulties in preparing the 5 dual-purpose tissues, and all 10 lamellar transplants were completed successfully. At the 6-month follow-up, the mean best-corrected distance visual acuity improved from 20/250 to 20/80 in the DALK patients, and from 20/300 to 20/25 in the DMEK patients. Postoperative complications after DALK included retained viscoelastic agent at the interface in 1 patient and a double anterior chamber managed with rebubbling in another. After DMEK, a peripheral partial graft detachment occurred in 1 patient and was managed successfully with rebubbling. All corneas demonstrated clarity on slit-lamp examination. CONCLUSIONS: Single-donor corneal tissue can be effectively used for both DALK and DMEK, and may represent a more efficient use of corneal tissue. Complications with the preparation of dual-purpose tissue were not encountered.

Outcomes of photorefractive keratectomy following laser in situ keratomileusis: a cohort study.

OBJECTIVE: To analyze the outcomes of photorefractive keratectomy (PRK) on residual myopia and hyperopia post-laser in situ keratomileusis (LASIK) and to compare these results with PRK on eyes without previous laser refractive surgery. DESIGN: Retrospective comparative cohort study. PARTICIPANTS: Patients undergoing PRK between 2006 and 2010 were reviewed. METHODS: Patients were divided into 4 groups, myopic or hyperopic PRK post-LASIK (mPRK-PL and hPRK-PL, respectively) and myopic or hyperopic PRK on corneas without previous laser refractive surgery (mPRK and hPRK, respectively). Uncorrected and corrected distance visual acuity, mean refractive spherical equivalent (MRSE), and mean keratometry and aberrations (total, higher order [HOA], coma, trefoil, and spherical aberration) were recorded at months 3 and 6 postoperatively, as were complications and attempted versus achieved MRSE. RESULTS: Thirty-three eyes of 25 patients who underwent PRK post-LASIK (21 eyes of 14 patients for hPRK-PL and 12 eyes of 11 patients for mPRK-PL) and 35 eyes of 21 patients who underwent PRK on virgin eyes (11 eyes of 8 patients for hPRK and 24 eyes of 13 patients for mPRK) were included in the study. The only significant differences in outcomes were found to be HOA at 3 months for hPRK-PL as compared with both hPRK and mPRK. Achieved MRSE was significantly different from expected MRSE for hPRK-PL at 3 months postoperatively. No haze- or flap-related complications were observed. CONCLUSION: Outcomes of PRK were not different in myopic and hyperopic corrections post-LASIK by 6 months or when compared with PRK in virgin eyes. HOA may render hPRK-PL results less predictable early in the postoperative period.

Genetic Risk Evaluation in Wet Age-Related Macular Degeneration Treatment Response.

OBJECTIVE: To evaluate the pharmacogenetic relationship between CFH haplotypes and single nucleotide polymorphisms (SNPs) with response to ranibizumab treatment for neovascular age-related macular degeneration (nAMD). PATIENTS AND METHODS: This was a prospective cohort study involving 70 treatment-naive nAMD patients. Patients were genotyped for CFH haplotypes and SNPs in the C3, ARMS2, and mtDNA genes. Visual acuity and central macular thickness were assessed at baseline and during 6 monthly follow-up visits. Multivariate logistic regression was used to determine the association between genotypes and a gain of ≥15 letters at the 6-month endpoint after adjusting for potential confounders. RESULTS: CFH haplotypes were associated with a gain of ≥15 letters at the 6-month endpoint (p = 0.046). Patients expressing protective haplotypes were more likely to achieve a gain of ≥15 letters relative to the greatly increased risk haplotypes [OR 6.58 (95% CI: 1.37, 31.59)]. CONCLUSION: CFH is implicated in nAMD patient treatment response to ranibizumab.

Type 1 Boston keratoprosthesis: outcomes at two Canadian centres.

OBJECTIVES: To report the outcomes of patients who underwent Boston type 1 keratoprosthesis (Kpro) surgery at the University Health Network (Toronto, Ont.) and the University of Ottawa Eye Institute (Ottawa, Ont.) between June 2008 and July 2013. DESIGN: Retrospective case series. PARTICIPANTS: Forty-four eyes of 43 patients who underwent Kpro surgery. METHODS: A retrospective review was conducted of all Kpro procedures performed by 4 attending cornea surgeons. The preoperative characteristics and postoperative course of each patient were analyzed. RESULTS: In 31 eyes (70%), the primary indication for a Kpro was failed corneal transplantation. The remaining 13 eyes (30%) had Kpro as a primary procedure. In all eyes, preoperative visual acuity (VA) was 20/150 or worse, with 39 eyes (89%) having a VA of counting fingers, hand movement, or light perception. Mean follow-up time was 21 ± 12 months (range 12-57 months). The retention rate at the last follow-up was 95%. Best-achieved median VA was 20/100 (range 20/20 to no light perception [NLP]), with 37% of patients achieving a VA of >20/40 at some point during their postoperative course. At the last follow-up, median VA was 20/400 (range 20/30 to NLP). The 2 most common complications included retroprosthetic membrane formation (23 eyes, 52%) and elevated intraocular pressure (10 eyes, 23%). There were 5 cases (11%) of stromal melt and 1 case (2%) of infective keratitis. CONCLUSIONS: This study demonstrates that Kpro improves VA in a majority of cases, and is a viable option in situations in which there is a poor prognosis for traditional penetrating keratoplasty.

Polarimetric Interferometry for Assessment of Corneal Stromal Lamellae Orientation.

PURPOSE: To analyze corneal stromal lamellae orientation in normal subjects and patients with various corneal conditions using a polarimetric interferometer. METHODS: Thirty-two healthy control subjects (59 eyes) and 16 patients (22 eyes) with corneal conditions or postkeratoplasty were included in the study. All patients were imaged using the interferometer and slit lamp photography. The interferometer produces an orthogonal cross-like image of stromal lamellae by illuminating the cornea in phase-light polarization angle. Corneal haze was graded on a scale from 0 to 4. Interferometer cross-like images were graded on a scale from 0 to 5 by a masked observer. Keratometry, corneal central pachymetry, and optical densitometry were obtained with Scheimpflug corneal tomography. RESULTS: The cross-like image was observed in 31 of 32 healthy control subjects (58 of 59 eyes) and in 13 of 16 patients (19 of 22 eyes). The image was not detectable in 3 patients, 1 with total corneal neovascularization and scarring, 1 with central leukoma, and 1 with failed deep lamellar keratoplasty. Corneal haze was the main factor obscuring the cross-like image (P < 0.05). Clarity of the images was influenced by older age, steeper keratometry, higher pachymetry, and optical density (P < 0.05). There was no correlation between the orientation of the keratometric axes and the orientation of the 2 arms of the cross-like image (P > 0.05). CONCLUSIONS: Corneal stromal lamellae orientation can be efficiently assessed and displayed as a cross-like image by the polarimetric interferometer. Stromal lamellae orientation imaging may have potential implications in corneal diagnostics and surgery.

Fibrin glue versus autologous blood for conjunctival autograft fixation in pterygium surgery.

OBJECTIVE: To compare the outcomes between autologous blood- and fibrin glue-fixated conjunctival autografts in pterygium excision surgery. DESIGN: Retrospective case series. PARTICIPANTS: Forty eyes of 40 patients who had a primary nasal pterygium excision. METHODS: A retrospective comparative case series of 40 eyes (40 patients) that had a primary nasal pterygium excision. All eyes had a conjunctival autograft from the superior bulbar conjunctiva to cover the scleral bed. Twenty eyes (20 patients) had fixation of the autograft using autologous blood (AB), and 20 eyes (20 patients) had fixation using fibrin glue (FG). One year of follow-up data included conjunctival graft stability (graft loss, graft retraction), pterygium recurrence, visual acuity, and postoperative complications. Descriptive and inferential statistics were performed. RESULTS: Intraoperatively, no complications occurred in either group. Graft loss occurred in 6 patients in the AB group, compared with none in the FG group. Graft retraction occurred in 3 patients in the AB group and 2 patients in the FG group. At 1 year postoperatively, pterygium recurrence occurred in 4 patients in the AB group and 1 patient in the FG group. One patient in the AB group developed a small pyogenic granuloma that resolved by 6 months with conservative management. Visual acuity remained stable in both groups. CONCLUSIONS: Conjunctival autograft fixation with autologous blood resulted in less stable conjunctival autografts and a higher recurrence rate compared with fixation with fibrin glue.

Risk factors for the development of ocular graft-versus-host disease (GVHD) dry eye syndrome in patients with chronic GVHD.

BACKGROUND: To investigate the factors associated with the development of ocular graft-versus-host disease (oGVHD) dry eye syndrome (DES) in patients with chronic GVHD (cGVHD) after receiving allogenic haematopoietic stem cell transplantation (AHSCT) METHODS: A retrospective chart review of patients receiving AHSCT between 1998 and 2013 at the Bone Marrow Transplant Unit of the British Columbia Cancer Agency was carried out. Demographic and clinical data from both donors and recipients were obtained. The diagnostic criteria for the development of oGVHD DES from the National Institutes of Health were used to identify patients with the disease. Descriptive and inferential statistics were carried out. RESULTS: A total of 146 patients with a median follow-up time of 24.0 months (range 11.3-249.7 months) were included in this study. Sixty-six (45.2%) patients were women. Seventy-seven (52.7%) patients had oGVHD DES. The median age of patients was 57 years (range 25-71 years). Compared with other ethnicities, Caucasian patients were less likely to develop oGVHD DES, with an OR of 0.29 (p=0.01). Patients who received a transplant from Epstein-Barr-positive donors had a higher prevalence of oGVHD DES (OR=4.39, p=0.01). This was also found in patients with the following systemic involvement of cGVHD: grade 1-3 cGVHD skin involvement (OR=1.57, p=0.01), oral involvement (OR=2.51, p=0.01) and liver involvement (p=0.04). Patients with grade 2-3 overall cGVHD were also more susceptible to oGVHD DES (OR=2.72, p<0.001). CONCLUSIONS: This study identified risk factors associated with a higher prevalence of oGVHD DES in post-AHSCT patients with cGVHD.

Evaluation of a new technique for preparation of endothelial grafts for descemet membrane endothelial keratoplasty.

PURPOSE: The purpose of this study was to compare the Muraine technique, a relatively new method for preparing endothelial grafts for Descemet membrane endothelial keratoplasty (DMEK), with the current standard submerged cornea using backgrounds away (SCUBA) peeling technique. METHODS: This study was a prospective ex vivo investigation. In a wet-lab setting, 20 donor corneas were prepared for DMEK using The Muraine technique and 20 donor corneas using the SCUBA technique. In each of the technique groups, 10 corneas were prepared by a corneal surgeon and 10 were prepared by a corneal fellow. Primary outcome measures were the time needed to prepare endothelial grafts and the number of graft tears. RESULTS: In the SCUBA technique, median time to prepare grafts was shorter for both the surgeon (301 ± 85 seconds) and fellow (523 ± 58 seconds) compared with the Muraine technique (surgeon, 359 ± 83 seconds; fellow, 543 ± 44 seconds). However, these findings were not statistically significant (surgeon, P = 0.33; fellow, P = 0.24; pooled, P = 0.46). There was a statistically significant difference between surgeon time and fellow time for each technique (SCUBA technique, P = 0.0005; Muraine technique, P = 0.002). In the Muraine technique, there were 5 graft tears (surgeon = 2, fellow = 3), and no graft tears in the SCUBA technique, which was statistically significant (P = 0.047). CONCLUSIONS: The present study demonstrates that the SCUBA technique may be a more effective technique to prepare endothelial donor grafts for DMEK.

Sutureless intrascleral fixation of a custom-tailored iris prosthesis with an intraocular lens.

UNLABELLED: We describe a technique for sutureless intrascleral fixation of a 3-piece intraocular lens (IOL) and custom silicone iris prosthesis complex to address the optical and functional issues of aphakia and aniridia, as well as to restore excellent cosmesis. The 3-piece IOL is anchored to the iris prosthesis using the belt-loop technique. We believe the intrascleral haptic fixation is overall a more robust fixation method in patients with aphakia and aniridia, who are often younger and require a long-lasting anterior segment reconstruction. FINANCIAL DISCLOSURE: Dr. Ahmed is a consultant to Alcon Laboratories, Inc., and Abbott Medical Optics, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

Incidence, morbidity, and mortality of Terson syndrome in Hamilton, Ontario.

OBJECTIVE: Evaluate the incidence, neurologic morbidity, and mortality of patients with Terson syndrome. METHODS: Consecutive patients admitted to the Hamilton General Hospital from May 2012 to May 2013 with a diagnosis of spontaneous subarachnoid hemorrhage (SAH) were recruited. Funduscopic examinations were performed under pharmacological mydriasis. Outcome measures included: (1) the presence or absence of Terson syndrome; (2) The Glasgow Coma Scale (GCS), Hunt and Hess scale (H&H), and SAH Fisher score upon admission to the hospital; (3) the modified Rankin score upon discharge; and (4) and all-cause mortality. RESULTS: Forty-six patients were included and 10 had Terson syndrome (21%). The median H&H, GCS, and Fisher scores were 4, 6.5, and 4.0 for patients with Terson syndrome vs. 2, 14, and 3 for patients without Terson syndrome (p=0.0032, 0.0052, and 0.031), respectively. The median Rankin score was 6 for patients with Terson syndrome vs. 3.5 for patients without Terson syndrome (p=0.0019). The odds of all-cause mortality with Terson syndrome vs. no Terson syndrome was 12: 1 (95% confidence interval 2.33-61.7), p =0.003. Only four of the 10 patients with Terson syndrome survived. CONCLUSIONS: Based on this study, approximately one-fifth of patients admitted to the hospital with a spontaneous SAH could have Terson syndrome. Patients with Terson syndrome have significantly worse GCS and H&H scores upon admission to the hospital, lower modified Rankin scores upon discharge, and greater mortality. Thus, Terson syndrome is not rare among patients with SAH and carries a worse prognosis.

Simple technique to measure toric intraocular lens alignment and stability using a smartphone.

Toric intraocular lenses (IOLs) are commonly implanted to correct corneal astigmatism at the time of cataract surgery. Their use requires preoperative calculation of the axis of implantation and postoperative measurement to determine whether the IOL has been implanted with the proper orientation. Moreover, toric IOL alignment stability over time is important for the patient and for the longitudinal evaluation of toric IOLs. We present a simple, inexpensive, and precise method to measure the toric IOL axis using a camera-enabled cellular phone (iPhone 5S) and computer software (ImageJ).