Archive | September 2012

Chariots of “Fire”

Well we did it! ‘Anglia Ruskin Optometry’ turned up, and ran the Chariots of Fire race, enjoyed it, and raised some money for our favourite local charities.

What we’ll perhaps keep a bit quieter about is that we were 305th out of the 308 teams that finished! Given that we’re not that good at running, but we did it anyway, maybe you could find it in your heart to sponsor us at our fundraising page – it’ll stay open for a time, and any amount is much appreciated!

Adjusting to visual loss

Daryl and I have just had a paper accepted in Investigative Ophthalmology and Visual Science (Tabrett & Latham, Adjustment to vision loss in a mixed sample of adults with established visual impairment) that looks at the factors that are related to how well someone adjusts to being visually impaired. As outcome measure, we used our AS-WAS questionnaire (Acceptance and Self-Worth Adjustment Scale, OVS 87:899, 2010), which is a refined version of the Nottingham Adjustment Scale. Factors associated with the poorer adjustment were higher levels of depressive symptoms, higher scores on the personality trait of neuroticism and lower scores on the personality trait of conscientiousness. This suggests  that as clinicians, we would do well to try and identify people who may well adjust poorly to visual impairment in order to try and put the appropriate support in place from an early stage. Factors that weren’t associated with the level of adjustment included the severity of visual loss, and the duration of visual impairment. This suggest that people wth VI could benefit from support in adjusting to life with visual impairment at any point following diagnosis, and regardless of the level of visual loss. A link to the early view paper will follow soon.

Chariots of Fire

A group of us from Anglia Ruskin Vision and Hearing Sciences are running the Chariots of Fire relay race around the iconic Cambridge Backs and Colleges this Sunday to raise money for a charity very close to our hearts – Cam Sight. Cam Sight support visually impaired people in Cambridgeshire, providing a wide range of rehabilitation services, and this year is their centenary year. They are aiming to raise £500,000  to build a new technology centre, and we are trying to do our bit to support them in reaching this target. If you could spare a couple of quid for this worthy cause, our fundraising page will take it from you! Comedy photos of lycra-clad lecturers to follow!

Guidelines for predicting performance with low vision aids

This paper is now available in the low vision feature issue of Optometry and Vision Science here. I am pleased with this paper, as it has potential impact on how low vision clinicians carry out their visual function assessments: I’ll be amending my undergraduate teaching this year to take the findings into account, and would be very interested to hear from anyone who puts the recommendations of the paper into practice in their clinical assessments.

In essence, what we have found is that how well a visually impaired patient will read with a low vision aid / magnifier can be predicted from just a couple of standardised tests of clinical visual function. Firstly, measure acuity on a reading chart at a fixed distance with an appropriate add (we used an MNRead chart at 40cm with a +2.50D, but a Bailey Lovie chart or other log scaled chart, and other distances such as 25cm with +4.00D would be just as good). Those with acuity better than 0.85 logMAR should be able to read print of 1M size (around N8-N10: see the appendix of the paper for a discussion!) and be able to read fluently (>80wpm) with an optical aid of appropriate magnification. For those with acuity worse than this, whether they will be able to read 1M print with a magnifier is then dependent on contrast sensitivity: if CS is better than 1.05logCS (normal or noticeable loss) success is likely, whereas worse CS than this (moderate or severe loss) suggests a patient will be unable to read 1M print, even with a magnifier. Those with acuity worse than 1.00logMAR, or who read slowly with a fixed add, are also less likely to read fluently with a magnifier.

As far as appropriate magnification is concerned, we also looked at how much magnification was needed to raise patients from just being able to see print of a certain size to being able to read it comfortably (at their maximum reading speed). For most people, 2x the magnification to just see print was suitable for reading close to their max reading speed, but a quarter of people required more (sometimes a lot more) than 2x extra magnification to reach maximum reading speed: my clinical interpretation of this would be to always try a bit more magnification than you think is needed for a specific print size to see if reading speed improves.

I hope these guidelines will help clinicians to be able to determine more quickly what the best options are for their patients, working out from just a couple of standard measures who is likely to be able to achieve their reading goals with optical aids, and who might be better served by early referral towards sensory substitution aids.