Low Vision Patients' Preference for Colored Filters and Illumination for Near Reading Determined by the LuxIQ/2
Low Vision Patients' Preference for Colored Filters and Illumination for Near Reading Determined by the LuxIQ/2
The effect of tinted filters and illumination on the visual performance of patients with low vision (i.e., individuals with reduced vision that is uncorrectable with glasses, surgery or treatments) has been a topic of research and discussion for many years, yet there is no current consensus or practice standard for the evaluation and recommendation of colored filters and/or illumination intensity. Anecdotally, there have been many subjective reports of improvement in visual function and comfort with the use of tinted lenses. Previous studies have attempted to elucidate the subjective improvements observed using vision tests, such as visual acuity and contrast sensitivity, and the findings have been inconsistent. Traditionally, filters and optimal illumination are prescribed clinically through a trial and error method, which involves trying various filters and lamps haphazardly to determine which if any are preferred by the patient. The investigators are proposing to evaluate whether the illumination and filters chosen in office by participants using a new assessment tool the LuxIQ/2 translate to overall patient comfort and improved speed, accuracy and print size while reading, and to evaluate whether participants have the same illumination and colored filter preference determined by the LuxIQ/2 in a clinical office setting and in their home environment. The investigators will evaluate whether participants prefer lighting determined by the new assessment tool the LuxIQ/2 in comparison to lighting determined by the OttLite Cobra in office.
All eligible patients with complaints of difficulty performing sustained reading tasks, such as reading books or magazines, will be evaluated for their preference for filter color and lighting using the LuxIQ/2.
Baseline distance visual acuity, contrast sensitivity, and near visual acuity, will be evaluated during initial presentation to the clinic as part of usual care using validated tests that are routinely performed during a low vision examination. Best-corrected distance visual acuity will be determined using the ETDRS (Early Treatment for Diabetic Retinopathy Study) chart. Contrast sensitivity will be evaluated using the MARS contrast sensitivity chart. Best-corrected near visual acuity will be evaluated using the Lighthouse Continuous Text Card. The LuxIQ/2 will be administered 3 times at 15-minute intervals. Lighting preferences will be evaluated 3 times using the Ott Lite Cobra. Each subject will be asked to choose between their preferred lighting conditions as determined by the OttLite Cobra and the LuxIQ/2, i.e each participant ill choose which lighting conditions is preferred for reading. The assessment tool (OTTLite Cobra or LuxIQ/2) which is performed first will be randomized for each participant. Microperimetry (a type of visual field test) will be conducted on all participants using the MAIA microperimeter at the NSU site only.
For subjects who do not appreciate an improvement in reading ability with a colored filter in office, we will obtain their written informed consent to include data collected during the clinical examination. For participants who do not appreciate an improvement in reading ability with a colored filter, but who appreciate an improvement in reading ability with white light as determined by the LuxIQ/2 in comparison to the OttLite Cobra, appropriate light bulb and desk lanp will be provided as determined by the LuxIQ/2. For participants who prefer the lighting determined using the Ottlite Cobra, they will be provided with an Ottlite Cobra desk lamp as well as their preferred settings on the device as determined through the in-office evaluation to be used at home. Participants to whom light bulb recommendations were provided or the Ottlite Cobra was recommended to improve lighting for their reading tasks, will be contacted by a research assistant 1 week after the in office assessment to complete a telephone interview which will consist of an Activity inventory questionnaire which will inquire about their difficulty performing near tasks using their previous light source as well as Ramulu's sustained reading test. The Ramulu sustained reading test will be performed twice during the phone interview, once with their previous lighting they were using at home before they obtained the new reading lamp (where they do most of their reading) and again with their new desk lamp. After 1 month, the research assistant will call the participant to repeat the Activity questionnaire inquiring about ability to perform near tasks using the new recommended lighting.
For participants who appreciate an improvement in reading ability with colored reading glasses, we will obtain their written informed consent to join the longer-term study.
Inclusion Criteria:
Exclusion Criteria: