Time to achieve best postoperative visual acuity following Boston keratoprosthesis surgery.

BACKGROUND/AIMS: To evaluate the time needed for patients with Boston type 1 keratoprosthesis (KPro) to reach their best-corrected visual acuity (BCVA) and all contributing factors. METHODS: We retrospectively reviewed 137 consecutive eyes from 118 patients, measured how long they needed to reach their BCVA and looked at factors that might affect this time duration including patient demographics, ocular comorbidities and postoperative complications. RESULTS: The mean follow-up was 5.49 years. The median time to BCVA postoperatively was 6 months, with 47% of patients achieving their BCVA by 3 months. The mean best achieved logMAR visual acuity was 0.71, representing a gain of 6 lines on the Snellen visual acuity chart. Postoperative glaucoma, retroprosthetic membrane (RPM) and endophthalmitis prolonged this duration. We found no correlation between the following factors and time to BCVA: gender, age, indication for KPro surgery, primary versus secondary KPro, number of previous penetrating keratoplasties, previous retinal surgery, intraoperative anterior vitrectomy and preoperative glaucoma. CONCLUSION: In our retrospective cohort, the majority of subjects reached their BCVA between 3 and 6 months after KPro implantation. This duration was significantly prolonged by the development of postoperative glaucoma, RPM and endophthalmitis.

The Attitudes of Canadian Ophthalmology Residents and Pre-Clerkship Medical Students at an Ontario Medical School Towards Homeless Individuals: A Cross-Sectional Study.

Purpose: This cross-sectional study assessed the attitudes of Canadian ophthalmology residents (PGY1-5) and pre-clerkship medical students (year 1 and 2) at the University of Toronto towards individuals experiencing homelessness.Methods: Residents and students were invited to complete the Health Professionals' Attitudes Towards the Homeless Inventory (HPATHI) tool to assess attitudes, interests and confidence in working with the homeless population on a 5-point Likert scale. Comparisons were made between residents and pre-clerkship learners and between junior and senior residents using the Fisher exact test and Mann-Whitney U test.Results: Responses were received from 114 of 220 ophthalmology residents (52%) and 315 of 534 (59%) pre-clerkship medical students. Ophthalmology residents had significantly more negative overall attitudes (pre-clerk median = 4.4, resident median = 4.1, both still indicating positive attitudes) and interests (pre-clerk median = 4.0, resident median = 3.3, residents with more neutral interests) towards working with the homeless population compared to pre-clerkship medical students. Using both statistical methods, beliefs were significantly more negative in 7 of 9 'Attitude' items, 5 of 5 'Interest' items and 1 of 4 'Confidence' items. Ophthalmology residents were only more positive in 1 of 4 of the 'Confidence' items. Attitudes were similar across PGY1-5 training years, except PGY4 and PGY5 residents were more negative than PGY1-3 residents on 1 of 5 'Interest' items.Conclusions: Ophthalmology residents have an at least neutral perception of individuals experiencing homelessness, while medical students have a more positive opinion. Studies exploring optimal ways to advocate for this population are needed for Canada's eye-care trainees.

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.

Neodymium Laser Treatment of IOP Rise Following Ex-Press Glaucoma Device Implantation: A Retrospective Review From 4 Institutions.

PRéCIS:: Our retrospective study examined the use of neodymium laser in 53 eyes with high intraocular pressure (IOP) following Ex-Press filtration device implantation. We found a statistically significant immediate IOP-lowering effect in all eyes, with a mean IOP reduction of 13.34±8.99 mm Hg, and a posttreatment IOP of 14.30±8.57 mm Hg (P<0.0001). Of a subset of 43 eyes on which 6 months follow-up IOP data was available, 28 eyes achieved treatment success (IOP<18 without further surgical interventions) with a mean IOP of 11.39±4.03 mm Hg at 6 months. PURPOSE: The purpose of this study was to report on the use of neodymium laser for treatment of eyes with IOP rise following Ex-Press glaucoma filtration device implantation. METHODS: We retrospectively examined the medical records of 73 patients who underwent Ex-Press device implantation at 4 medical institutions between 2007 and 2015 and subsequently developed an IOP rise. Enrollment criteria included patients with POAG on whom posttreatment IOP data is available. Indications for treatment with neodymium laser were an IOP above target and a flat bleb. To disrupt the presumed microblockage, the neodymium laser was aimed at the axial and relief ports of the Ex-Press device. Applanation tonometry measurements were followed up after neodymium treatment for variable time intervals. Success was defined as an IOP <18 mm Hg at 6 months without further surgical or laser-based glaucoma interventions. RESULTS: A total of 73 charts were reviewed. Twenty patients were excluded due to insufficient data or a diagnosis other than POAG. Data from 53 eyes of the remaining 53 patients was analyzed. The mean duration between Ex-Press implantation and rise in IOP requiring neodymium intervention was 34.2 months (range, 1.1 to 67.2). We found a statistically significant immediate IOP-lowering effect in all eyes, with a mean IOP drop of 13.34±8.99 mm Hg, and a mean posttreatment IOP of 14.30±8.57 mm Hg (P<0.0001). Of a subset of 43 eyes on which 6 months follow-up IOP data was available, 11 eyes required further glaucoma intervention (surgery or laser-based); 4 eyes had an IOP of ≥18 at 6 months. In the remaining 28 successful eyes, a sustained IOP<18 mm Hg was observed at 6 months, with a mean pressure of 11.39±4.03 mm Hg (P<0.0001). Hypotony (IOP<5) occurred in 3 eyes immediately following treatment and self-resolved by 1 week. CONCLUSION: Our retrospective case series suggests that neodymium laser is a potential consideration in eyes with sustained IOP rise after Ex-Press device implantation.

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.

Factors Influencing the Decision to Attend a Pediatric Emergency Department for Nonemergent Complaints.

OBJECTIVE: The objective of this study was to explore the factors associated with parents' decisions to bring their children to the pediatric emergency department (PED) for nonemergent concerns. METHODS: We conducted a cross-sectional survey at a tertiary-care, pediatric referral center emergency department. We surveyed caregivers of children triaged to low-acuity levels using the Pediatric Canadian Triage and Acuity Scale. We used descriptive statistics to report the proportion of patients who have a primary care physician, who attempted to contact any health care providers prior to coming to the PED, and other factors surrounding the decision to come to the PED. RESULTS: We approached 340 families, of which 300 were enrolled (uptake rate, 88.2%). We found that 32% (95% confidence interval, 0.26-0.37) attempted to contact another health care provider prior to coming to the PED, and 59% (95% confidence interval, 0.48-0.69) of those respondents were specifically instructed to come to the PED. The top 3 reasons for coming to the British Columbia Children's Hospital PED were (1) that it specializes in children, (2) child has medical issues previously managed at the same hospital, and (3) closest location to patient. CONCLUSIONS: Despite the majority of patients having a primary care physician, less than half of them actually contacted these providers (or another health care provider) before presenting to the PED for their nonurgent illness or injury. Of these, nearly two thirds were specifically instructed to come to the PED by the health care provider in the community.

Laser induced fluorescence spectroscopy of tetracene with large Ar, Ne, and H2 clusters in superfluid He nanodroplets.

Clusters of tetracene molecules with different numbers of attached (Ar)(N), (Ne)(N) and (H(2))(N) particles (N = 1-2000) are assembled inside superfluid He nanodroplets and studied via laser-induced fluorescence. The frequency shift of the fluorescence spectrum of the tetracene molecules is studied as a function of cluster size and pickup order of tetracene and cluster species. For (Ar)(N) and (Ne)(N) clusters, our results indicate that the tetracene molecules reside inside the clusters when tetracene is captured by the He nanodroplet before the cluster species; conversely, the tetracene molecules stay on the surface of the clusters when tetracene is captured after the cluster species. In the case of (H(2))(N) clusters, however, tetracene molecules reside inside the (H(2))(N) clusters irrespective of the pickup order. We conclude that (Ar)(N) and (Ne)(N) clusters are rigid at T = 0.38 K, while (H(2))(N) clusters of up to N = 2000 remain fluxional at the same temperature. The results may also indicate the occurrence of heterogeneous nucleation of the (H(2))(N) clusters, which is induced by the interaction with tetracene chromophore molecules.