Sjogren's Syndrome: A Clinical and Biochemical Analysis

Sjogren’s syndrome (SS) is a systemic autoimmune disease that presents to eye care practitioners with the hallmark symptom of “dry eye.” Stratifying dry eye patients as Sjogren’s positive or negative is a critical differential diagnosis, as SS patients have numerous systemic complications and a forty times greater risk of developing lymphoma. As such, management of this relatively common dry eye sub-population requires specialized care. Since a firm diagnosis requires testing that is both invasive and expensive, patients should be protected from these tests if they are not warranted. In this thesis, studies were therefore undertaken to determine if SS dry eye could be differentiated from other forms of dry eye using two methods: 1) standard clinical tests used in a multi-disciplinary Sjogren’s syndrome clinic and 2) subsequent biological evaluation of collected tear samples and cells from the ocular surface. The former would allow eye care practitioners to conduct appropriate tests and pose suitable questions to ifferentiate these subgroups, and the latter might serve in the future as a relatively non-invasive quantitative means of differentiating such groups through biomarkers

Dry Eye Diseases and Ocular Surgery: Practical Guidelines for Canadian Eye Care Practitioners

In 2014, the Canadian Dry Eye Disease Consensus Panel published Guidelines for screening, diagnosis and management of dry eye diseases (DED). These did not address the implications of DED for individuals who are being considered for or have recently undergone ocular surgery. DED is common in certain surgical cohorts, and the perisurgical setting poses specific challenges, both because surgery can complicate preexisting DED and because symptomatic and non-symptomatic DED place the patient at risk of poor surgical outcomes. The Consensus Panel has developed this Addendum to the 2014 Guidelines to offer guidance on DED care before and after ocular surgery

Lignes directrices pratiques pour les professionnels canadiens des soins oculovisuels concernant la sécheresse oculaire et la chirurgie de l’œil

En 2014, le Groupe de consensus canadien sur la sécheresse oculaire a publié un document intitulé Dépistage, diagnostic et prise en charge de la sécher-esse oculaire : guide pratique à l’intention des optométristes canadiens. Ce guide pratique ne traitait pas des répercussions de la sécheresse oculaire chez les personnes en voie de subir une intervention chirurgicale de l’œil ou ayant récemment subi ce genre d’intervention. La sécheresse oculaire est courante dans certaines cohortes ayant subi une intervention chirurgicale, et le contexte périopératoire pose des problèmes précis; d’une part parce qu’une intervention chirurgicale peut compliquer une sécheresse oculaire préexistante et, d’autre part, parce la sécheresse oculaire symptomatique et asymptomatique expose le patient au risque d’obtenir des résultats chirur-gicaux médiocres. Le groupe de consensus a élaboré cet addenda au guide pratique de 2014 pour offrir des conseils sur les soins relatifs à la sécheresse oculaire avant et après une intervention chirurgicale aux yeux

Canonical Grading Scales of Corneal and Conjunctival Staining Based on Psychophysical and Physical Attributes

Purpose: In this study, we apply psychophysical scaling principles based on physical (photometric) attributes of images to better understand the factors involved in clinician judgement of ocular surface staining and, using that knowledge, to develop photographic scales for the assessment of staining for dry eye (DE) and related conditions. Methods: Subjects with noninfectious ocular surface staining were enrolled at five clinical sites. Following instillation of fluorescein, photographs of corneal staining were taken every 30 seconds for at least 5 minutes. The same procedure was followed for conjunctival staining after instillation of 2 µl of 1% lissamine green. A subset of the best corneal and bulbar conjunctival staining images were anonymized and a spectroradiometer measured photometric attributes (luminance and chromaticity). The images were scaled psychophysically by study investigators, who participated in constructing grading scales based on physical and psychophysical analyses. The final grading scales were refined following consultation with outside DE experts. Results: Photographs were collected from 142 subjects (81% women), with an average age of 58 ± 17 years; 89% were diagnosed with DE. There was a monotonic relationship between between physical measurements and psychophysically scaled staining of both corneal (fluorescein) and bulbar (lissamine green) staining. Michelson contrast and u' (chromaticity) accounted for 66% and 64% of the variability in the psychophysically scaled images of fluorescein corneal and lissamine green conjunctival staining, respectively. Translational relevance: This paper provides examples of the first ever clinically usable ocular surface staining scales validated using psychophysical scaling and the physical attributes (luminance and chromaticity) of the staining itself. In addition, it provides a generalizable method for the development of other clinical scales of ocular appearance