The effect of cataract on early stage glaucoma detection using spatial and temporal contrast sensitivity tests

Background: To investigate the effect of cataract on the ability of spatial and temporal contrast sensitivity tests used to detect early glaucoma. Methods: Twenty-seven glaucoma subjects with early cataract (mean age 60 ±10.2 years) which constituted the test group were recruited together with twenty-seven controls (cataract only) matched for age and cataract type from a primary eye care setting. Contrast sensitivity to flickering gratings at 20 Hz and stationary gratings with and without glare, were measured for 0.5, 1.5 and 3 cycles per degree (cpd) in central vision. Perimetry and structural measurements with the Heidelberg Retinal Tomograph (HRT) were also performed. Results: After considering the effect of cataract, contrast sensitivity to stationary gratings was reduced in the test group compared with controls with a statistically significant mean difference of 0.2 log units independent of spatial frequency. The flicker test showed a significant difference between test and control group at 1.5 and 3 cpd (p = 0.019 and p = 0.011 respectively). The percentage of glaucoma patients who could not see the temporal modulation was much higher compared with their cataract only counterparts. A significant correlation was found between the reduction of contrast sensitivity caused by glare and the Glaucoma Probability Score (GPS) as measured with the HRT (p<0.005). Conclusions: These findings indicate that both spatial and temporal contrast sensitivity tests are suitable for distinguishing between vision loss as a consequence of glaucoma and vision loss caused by cataract only. The correlation between glare factor and GPS suggests that there may be an increase in intraocular stray light in glaucoma

Assessing the effect of independent prescribing for community optometrists and referral rates to hospital eye services in Scotland

Introduction: Since 2010, General Ophthalmic Services (GOS) legislation and Independent Prescribing (IP) enable community optometrists to manage primary eye conditions. No studies have assessed the effect of IP. We wished to determine the distribution of IP optometrists and associated hospital referral rates across Scotland. Methods: In 2019, FOI requests (General Optical Council and NHS Education Scotland) identified all registered IP optometrists in Scotland and their registered postcodes. Data regarding community eye examinations and referrals to HES since 2010 were gathered via Information Services Division of NHS Scotland. Results: As of March 2019, there were 278 IP optometrists in Scotland (278/1189; 23.4%). Two hundred eighteen IP optometrists work in 293 practices across 11 of Scotland’s 14 health boards. There was a strong correlation (r = +0.96) between population density and number of IP optometrists. Fifty-six percent of IP optometrists work in the two most deprived quintiles. Since IP’s introduction, there has been a marked increase in anterior segment supplementary visits (+290%). Optometry referrals to GPs have reduced by 10.5%, but referrals to HES have increased by 118% (to 96,315). There was no correlation between quantity of IP optometrists and referral rates to HES (r = −0.06, 95% CI −0.64 to 0.56, p = 0.86). Conclusions: This is the first analysis of IP optometrists and associated referral rates in Scotland. Despite good geographical distribution and increased supplementary attendances, optometric referrals to HES have doubled and continue to rise. We propose a ratio of primary, supplementary, non-referral and referral rates to discern the true impact of IP versus non-IP community optometric behaviour

Pro-donation behaviours of nursing students from the four countries of the UK

BACKGROUND: The effectiveness of the organ donation system depends on the health professionals involved in procurement and in dealing with donors and their families. Concerns about lack of knowledge and experience of organ donation have been expressed among such professionals but there is a paucity of literature to indicate the basis of such concerns and where knowledge may be lacking. Given that regional variations in organ donation rates exist in the UK, this study investigates knowledge about and attitudes towards organ donation among student nurses in different countries of the UK and examines regional variations. METHODS: A questionnaire was distributed to 667 student nurses (female:male = 582∶85) aged 18 to 50 years (mean [SD] 25.4 [7.1] years) recruited from a total of five Universities (Scotland, Wales, Northern Ireland, England) during the period of January to September 2011. RESULTS: Registration behaviour among participants was shown to vary depending upon many different factors that include birthplace, residency, fear of death and concerns of medical distrust. CONCLUSIONS: Regional variations in organ donation behaviour in the UK were found in the cohorts of student nurses who participated in this study. These variations include willingness to register and to donate specific body parts and not others. The relationship between attitude and behaviour and how this may influence the decision making process of organ donation, as well as the underlying factors that result in regional variations, require further investigation

Age-Related Variation in the Biomechanical and Structural Properties of the Corneo-Scleral Tunic

With increasing age, the mechanical performance of the cornea and sclera is impaired due to structural changes in the major structural proteins, namely collagens , proteoglycans and elastin. In addition, the level of hydration in the ocular tunic decreases over time. These structural changes profoundly impact on the biomechanical properties of the corneo-scleral tunic. This chapter focuses on the structural and biomechanical changes that occur in the corneo-scleral tunic with age. The techniques that are utilized in order to determine the mechanical properties of both the cornea and sclera are discussed, and a comprehensive review of studies which have characterized age-related changes in ocular biomechanics are presented. The cornea is found to increase in stiffness with age and all the characteristics of viscoelastic behavior (creep , stress-relaxation and hysteresis) decrease with age. Similarly, the stiffness of the sclera increases markedly with age although the reported magnitude of stiffening varies significantly from one study to another. This may be related to variations amongst the different techniques that have been utilized. Increased stiffening in the cornea and the sclera with age is strongly associated with the increase in collagen crosslinking that occurs as part of the natural aging process