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Abstract During the processing of water containing food materials, water transport can be driven by pressure from gas, capillarity, swelling, or gravity. To describe these various modes of pressure-driven transport using Darcy's law, permeability is a critical parameter for which few data are available, primarily as a result of measurement difficulties. Permeability in the flow of liquid water through potato tissue was estimated by approximating the plant cellular structure, measured directly using flow-through and indirectly using nuclear magnetic resonance. The data from the three approaches show the same order of magnitude 10−18 m2, and thus are in agreement with each other and results reported in the literature. The dynamics of porosity and permeability changes in fresh, water-saturated, and cooked samples were described using cellular structure changes as observed in microscopy images. Simple mechanistic equations for predicting permeability and porosity, which can include swelling and shrinkage, are proposed based on approximating the geometry of the cellular tissue. Data corroborated in three ways will provide permeability values with confidence, while the simple prediction equation will make a reasonable estimation of permeability possible for a large class of food products.

Purpose Corneal confocal microscopy (CCM) is an ophthalmic imaging technique that has been used to identify increased corneal immune cells in patients with immune-mediated peripheral neuropathy. Given that multiple sclerosis has an immune-mediated etiology, we have compared corneal immune cell (IC) density and near-nerve distance in different subtypes of patients with multiple sclerosis (MS) to controls. Methods This is a blinded, cross-sectional study conducted at a tertiary hospital. Patients with clinically isolated syndrome (CIS) (n = 9), relapsing-remitting multiple sclerosis (RRMS) (n = 43), secondary progressive multiple sclerosis (SPMS) (n = 22), and control subjects (n = 20) underwent CCM. The total, mature, and immature corneal IC density and their nearest nerve distance were quantified. Results The total IC density was higher in patients with MS (P = 0.02), RRMS (P = 0.01), and SPMS (P = 0.04) but not CIS (P = 0.99) compared to controls. Immature IC density was higher in patients with MS (P = 0.03) and RRMS (P = 0.02) but not SPMS (P = 0.10) or CIS (P = 0.99) compared to controls. Mature IC density (P = 0.15) did not differ between patients with MS and controls. The immature IC near-nerve distance was significantly greater in patients with MS (P = 0.001), RRMS (P = 0.007), and SPMS (P = 0.002) compared to controls. Immature IC density correlated with the Symbol Digit Modalities Test (r = -0.281, P = 0.02) and near-nerve distance correlated with the Expanded Disability Status Scale (r = 0.289, P = 0.005). Conclusions In vivo CCM demonstrates an increase in immature IC density and the near-nerve distance in patients with MS. These observations merit further studies to assess the utility of CCM in assessing neuroimmune alterations in MS. Translational relevance Multiple sclerosis is an immune-mediated neurodegenerative disease. Dendritic cells mediate communication between the innate and adaptive immune systems. We have used in vivo CCM to show increased corneal ICs and suggest it may act as an imaging biomarker for disease status in patients with MS.

Purpose To evaluate the ability of the 8th edition of the American Joint Committee on Cancer (AJCC) Cancer Staging Manual to estimate metastatic and mortality rates for children with retinoblastoma (RB). Design International, multicenter, registry-based retrospective case series. Participants A total of 2190 patients from 18 ophthalmic oncology centers from 13 countries over 6 continents. Methods Patient-specific data fields for RB were designed and selected by subcommittee. All patients with RB with adequate records to allow tumor staging by the AJCC criteria and follow-up for metastatic disease were studied. Main Outcome Measures Metastasis-related 5- and 10-year survival data after initial tumor staging were estimated with the Kaplan–Meier method depending on AJCC clinical (cTNM) and pathological (pTNM) tumor, node, metastasis category and age, tumor laterality, and presence of heritable trait. Results Of 2190 patients, the records of 2085 patients (95.2%) with 2905 eyes were complete. The median age at diagnosis was 17.0 months. A total of 1260 patients (65.4%) had unilateral RB. Among the 2085 patients, tumor categories were cT1a in 55 (2.6%), cT1b in 168 (8.1%), cT2a in 197 (9.4%), cT2b in 812 (38.9%), cT3 in 835 (40.0%), and cT4 in 18 (0.9%). Of these, 1397 eyes in 1353 patients (48.1%) were treated with enucleation. A total of 109 patients (5.2%) developed metastases and died. The median time (n = 92) from diagnosis to metastasis was 9.50 months. The 5-year Kaplan–Meier cumulative survival estimates by clinical tumor categories were 100% for category cT1a, 98% (95% confidence interval [CI], 97–99) for cT1b and cT2a, 96% (95% CI, 95–97) for cT2b, 89% (95% CI, 88–90) for cT3 tumors, and 45% (95% CI, 31–59) for cT4 tumors. Risk of metastasis increased with increasing cT (and pT) category (P Conclusions Multicenter, international, internet-based data sharing facilitated analysis of the 8th edition AJCC RB Staging System for metastasis-related mortality and offered a proof of concept yielding quantitative, predictive estimates per category in a large, real-life, heterogeneous patient population with RB.

Abstract Background The incidence of syphilis has been increasing worldwide in the last 20 years, disproportionately impacting those living with human immunodeficiency virus (HIV). Alongside this increase, several jurisdictions have reported increasing incidences of syphilis-related complications, including ocular syphilis. We sought to characterize ocular syphilis cases in British Columbia (BC), Canada. Methods This case-control study compared ocular syphilis cases, matched (1:4) to syphilis controls, that were diagnosed in BC between January 2010 and December 2018. Multivariable logistic regression was used to identify potential correlates of ocular syphilis, where variables were included in the final model if significant (P ≤ .05). Results During the study period, there were 6716 syphilis diagnoses, including 66 (0.98%) ocular syphilis cases. The median age of cases was 49.5 years (interquartile range 39–59). Most (87.8%) patients were male, where 54.6% identified as men who have sex with men. The most common ophthalmologic diagnosis was panuveitis (42.4%). Of ocular syphilis patients, 48.5% were living with HIV at the time of their syphilis diagnosis, compared to 26.4% of controls (P = .001). The proportion of syphilis cases with ocular syphilis increased from 0.48% in 2010 to 0.83% in 2018. The final multivariable model demonstrated correlates between ocular syphilis and early syphilis stage, including primary/secondary (odds ratio [OR] 4.96, 95% confidence interval [CI] 1.86–13.24) and early latent (OR 4.29, 95% CI 1.62–11.34) stages, and HIV serostatus (OR 2.16, 95% CI 1.14–4.09). Conclusions Ocular syphilis increased over the study period, both in absolute numbers and as a proportion of all syphilis cases, a finding consistent with other jurisdictions. These findings highlight the importance of vigilance for ocular syphilis, to avoid diagnostic and treatment delays.

Purpose To investigate retinal blood flow and oxygen saturation changes in patients diagnosed with retinopathy following plaque radiation treatment to treat choroidal melanoma. Methods Eight patients (mean age 55.75 years, SD 12.58 years) who have developed unilateral ischaemic radiation-related retinopathy as confirmed by wide-field fluorescein angiography were recruited for the study. The fellow eye with no other ocular or retinal pathology was used as control. Both eyes underwent measurement of total retinal blood flow (TRBF) and retinal blood oxygen saturation using prototype methodologies of Doppler Spectral Domain Optical Coherence Tomography (OCT) and Hyperspectral Retinal Camera, respectively. Results The average TRBF in the retinopathy eye was significantly lower compared to the fellow eye (33.48 ± 12.73 μl/min versus 50.37 ± 15.26 μl/min; p = 0.013). The arteriolar oxygen saturation (SaO2 ) and venular oxygen saturation (SvO2 ) were higher in the retinopathy eye compared to the fellow eye (101.11 ± 4.26%, versus 94.45 ± 5.79%; p = 0.008) and (62.96 ± 11.05% versus 51.24 ± 6.88%, p = 0.051), respectively. Conclusion The ionizing radiation seems to have an impact on the TRBF, SaO2 and SvO2 , clinically presenting similar to a rapidly developing diabetic retinopathy. The results show an altered retinal vascular physiology in patients with radiation-related retinopathy.

AbstractCell-based therapies in the retina have been associated with the recovery of visual function in animal models of retinal degeneration. This review covers the current status of such therapies with regard to the source of the donor cells, their integration, and their impact on the degenerating host retina. Emphasis is also put on the importance of a careful interpretation of what is meant by “recovery of visual function”. Two main approaches are considered here: (1) the use of human embryonic stem cell derived retinal pigment epithelial (RPE) cells to rescue photoreceptors in an animal model of RPE defect; and (2) the use of photoreceptor precursors to repair the degenerating neural retina. The current conclusions are that major hurdles have to be dealt with, such as finding an appropriate and ethically compliant donor cell source that would yield protracted survival and integration of the replacement retinal cells, and that there is no evidence yet that cell-based therapies can allow the long-term preservation or recovery of conscious vision.

Purpose Retinitis pigmentosa (RP) describes a complex group of inherited retinal dystrophies with almost 300 reported genes and loci. We investigated the genetic etiology of autosomal recessive RP (arRP) in a large kindred with 5 affected family members, who reside on the island of Newfoundland, Canada. Methods Genetic linkage analysis was performed on 12 family members (Infinium HumanOmni2.5-8 BeadChip). Whole exome sequencing analysis (Illumina HiSeq) was performed on one affected individual. A custom pipeline was applied to call, annotate, and filter variants. FishingCNV was used to scan the exome for rare copy number variants (CNVs). Candidate CNVs subsequently were visualized from microarray data (CNVPartition v.3.1.6.). MERTK breakpoints were mapped and familial cosegregation was tested using Sanger Sequencing. Results We found strong evidence of linkage to a locus on chromosome 2 (logarithm of the odds [LOD] 4.89 [θ = 0]), at an interval encompassing the MERTK gene. Whole exome sequencing did not uncover candidate point mutations in MERTK, or other known RP genes. Subsequently, CNV analysis of the exome data and breakpoint mapping revealed a 25,218 bp deletion of MERTK, encompassing exons 6 to 8, with breakpoints in introns 5 (chr2:112,725,292) and 8 (chr2:112,750,421). A 48 bp insertion sequence was buried within the breakpoint; 18 bps shared homology to MIR4435-2HG and LINC00152, and 30 bp mapped to MERTK. The deletion cosegregated with arRP in the family. Conclusions This study describes the molecular and clinical characterization of an arRP family segregating a novel 25 kb deletion of MERTK. These findings may assist clinicians in providing a diagnosis for other unsolved RP cases.

Abstract Purpose To investigate changes in higher order ocular aberrations (HOA) induced by the administration of 0.15% sodium hyaluronate tear enhancer (TE) and meibomian gland expression (ME) on the tear film of normal subjects. Methods HOA values were obtained from the corneal surface (CS) and whole eye (WE), using a corneal topographer and Shack–Hartmann aberrometer, from both eyes of 50 subjects (25 females, mean age ± sd 32.5 ± 11.0 years, and 25 males, 33.88 ± 11.2 years) for two pupil sizes (3 and 6 mm) in a dark environment. One drop of Blink Contacts™ (Abbott Medical Optics) was instilled into the right eye and HOA measurements repeated after 30 s. After 1 h, the meibomian glands of the left lower eyelid were gently squeezed and HOA measurements repeated after 30 s. Results There was no significant difference for CS and WE root mean square (RMS) HOAs between right and left eyes before (both pupil sizes) and after TE use or ME (3 mm pupil). For 6 mm pupil, TE use significantly reduced the WE RMS HOA (p Z 4 0 (0.297 ± 0.136 to 0.053 ± 0.069), and Z 5 5 (0.221 ± 0.372 to 0.098 ± 0.121) while ME significantly increased CS RMS HOA (p Z 3 − 3 (0.799 ± 1.178 to 1.302 ± 1.991) and Z 4 4 (0.594 ± 1.184 to 0.988 ± 1.463). In general, the change in HOA was significantly correlated with the initial value before TE use or ME (p Conclusion There were no detectable differences between right and left eyes. For the 6 mm pupil, the tear enhancer tended to improve optical performance of the WE and meibomian gland expression tended to reduce the optical performance at the CS.

The subcommittee reviewed the prevalence, incidence, risk factors, natural history, morbidity and questionnaires reported in epidemiological studies of dry eye disease (DED). A meta-analysis of published prevalence data estimated the impact of age and sex. Global mapping of prevalence was undertaken. The prevalence of DED ranged from 5 to 50%. The prevalence of signs was higher and more variable than symptoms. There were limited prevalence studies in youth and in populations south of the equator. The meta-analysis confirmed that prevalence increases with age, however signs showed a greater increase per decade than symptoms. Women have a higher prevalence of DED than men, although differences become significant only with age. Risk factors were categorized as modifiable/non-modifiable, and as consistent, probable or inconclusive. Asian ethnicity was a mostly consistent risk factor. The economic burden and impact of DED on vision, quality of life, work productivity, psychological and physical impact of pain, are considerable, particularly costs due to reduced work productivity. Questionnaires used to evaluate DED vary in their utility. Future research should establish the prevalence of disease of varying severity, the incidence in different populations and potential risk factors such as youth and digital device usage. Geospatial mapping might elucidate the impact of climate, environment and socioeconomic factors. Given the limited study of the natural history of treated and untreated DED, this remains an important area for future research.