Medical hypothesis, discovery & innovation in optometry

Background: Low vision is a major public health concern. This study was aimed at describing the characteristics of patients attending a low vision rehabilitation clinic.
Methods:  In this retrospective study, we reviewed the medical records of patients with low vision attending a low vision rehabilitation clinic at a tertiary referral center over 7 years. We extracted the following data from each record: age, sex, education level, employment status, chief complaints with respect to vision, associated ocular diseases, status of previously prescribed optical devices, uncorrected distance and near visual acuities, best-corrected distance and near visual acuities, the status of prescribed optical devices, and cooperation status of patients during optometric examination.
Results: Finally, 567 patients were included with a mean (standard deviation) age of 40.46 (28.34) years and a male-to-female ratio of 338 (59.6%) to 229 (40.4%). The majority of participants were cooperative (98.4) with a high rate of unemployment (90.5%) and low education level. Half of the patients had moderate vision impairment (49.2%). Age-related macular degeneration (ARMD) was the commonest cause (21.3%). Reading was the most frequent complaint (22.9%) and combination of three complaints (reading, writing, and facial recognition) were recorded in 54.7% of patients. Multivariate logistic regression analysis revealed that the likelihood of difficulties in in-house-activities, reading, facial recognition and social activities, and driving increased with age (odds ratios of 1.39, 1.31, 1.24, and 1.22 per 10-year increment in age) (all P < 0.05). The likelihood of expressing three complaints (reading, writing, and facial recognition together) increased with visual acuity. Besides, men were more likely to have difficulties in driving and reading, while women were more likely to have difficulties in facial recognition and social activities or in-house activities (all P < 0.05). Optical devices for distance or near were prescribed for most patients.
Conclusions: Most patients were men and unemployed. The most common category and cause of low vision were moderate vision impairment and ARMD, respectively. Reading, writing, and facial recognition was the most common complaints. Optometrists should address these findings during rehabilitation therapy in patients with low vision.

Background: The worldwide spread of the coronavirus disease (COVID-19) pandemic in 2020, followed by lockdowns, forced children to be in home confinement with increased screen time, leading to rapid progression of myopia and an increase in the prevalence of myopia. This study was aimed at determining if myopia progression seen in evidence-based practice resulted from the COVID-19 lockdown or delayed follow-ups.
Methods: A retrospective review of case sheets of patients visiting the pediatric department of a tertiary care eye hospital in Mumbai, India, was conducted from 2017 onwards. We enrolled all children with myopia who had attended at least one follow-up visit before the COVID-19 lockdown and at least one follow-up visit post-lockdown. The spherical equivalent (SEQ) of refractive error values at baseline and pre- and post-COVID-19 lockdown follow-ups (hereinafter referred to as the “first” and “second” follow-ups, respectively) were recorded. The duration between baseline and the first follow-up visit and between the first and second follow-up visits were noted.
Results: We enrolled 112 eyes of 56 children, including (62.5%) boys and (37.5%) girls, with a mean (standard deviation [SD]) age of 9.54 (2.82) years. The mean (SD) SEQ values at baseline and first and second follow-ups were - 4.74 (3.83), - 5.46 (3.81), and - 6.42 (3.66) D, respectively. The mean change in SEQ, mean SEQ myopia progression, and rate of myopia progression per month differed significantly between the first and second follow-up visits (all P < 0.05). However, the myopia degree did not change significantly between the first and second follow-ups in eyes with low, moderate, or high myopia (all P > 0.05). The mean (SD) duration of the first follow-up was 14.57 (5.68) months, while that between the first and second follow-ups was 27.96 (9.18) months, showing a significant difference (P < 0.05).
Conclusions: Our findings suggest that a longer gap between follow-up visits and myopia progression per month should be factored into the management of myopia. Considering that young children are more vulnerable, preventive measures and school reforms should be urgently implemented in India. Further retrospective multicenter studies with a larger sample size of eyes, including various refractive errors over a longer period, are required to verify these findings.

Background: Visual impairment (VI) in patients with diabetes mellitus (DM) worsens as the disease progresses. Therefore, quality of life (QOL) may also be affected. Furthermore, in the absence of macular involvement, some patients may benefit from visual intervention. However, not many Malaysians with known DM had their eyes screened or used correctable spectacles. Consequently, the QOL and VI status of patients with DM in Malaysia remain unclear. This study was aimed at determining the impact of optometric intervention on the QOL and VI status of adults with type II DM.
Methods: This was a quasi-self-controlled, experimental study involving adults with known type II DM. We conducted face-to-face interviews using the low vision quality-of-life questionnaire (LVQOL). The habitual visual acuity (VA) of all participants was recorded. All participants underwent fundus photography to grade diabetic retinopathy (DR) in both eyes. Correctable VA was determined following subjective refraction when the best-corrected distance visual acuity (BCDVA) was 6/9 and better. After a 3-week adaptation to the prescribed refractive error correction, LVQOL was repeated via a phone interview.
Results: A total of 47 participants (31 women and 16 men) were recruited. The age range was 32 – 59 years, and the baseline habitual VA was 6/5 – 6/36. Only 19.2% (n = 9) of the participants had their vision tested and wore glasses; however, some were uncomfortable with the current corrections. All patients had uncorrected refractive errors, namely, hyperopic astigmatism (46.8%), myopic astigmatism (38.3%), hyperopia (6.4%), myopia (4.3%), and antimetropia (4.3%). Among the 47 participants, 89.4% (n = 42) had uncorrected presbyopia. The mean (standard deviation [SD]) LVQOL score at baseline was 91.92 (17.29), which improved significantly with visual intervention to 122.77 (3.18) (P < 0.05). Refractive error corrections significantly improved the visual impairment status (P < 0.05), as all participants achieved a BCDVA of 6/9 and better.
Conclusions: Our findings indicate that optometric intervention is effective in improving the LVQOL and visual impairment status of adults with type II DM. Further clinical optometric studies on type II DM with DR with a longer follow-up should be carried out to understand the clinical characteristics of this cohort and the impact of meticulous refractions on QOL in providing better services in the future.

Background: Vernal keratoconjunctivitis (VKC), a chronic bilateral eye disease, is a severe form of allergic conjunctivitis. Anterior-segment optical coherence tomography (AS-OCT) is a rapid, noninvasive, in vivo visualization modality for the anterior segment structures that has been used in diagnosing and staging diseases and assessing the treatment efficacy. We used anterior-segment optical coherence tomography (AS-OCT) to monitor the efficacy of the tacrolimus eye ointment in managing VKC.
Methods: In this prospective follow-up study, we included patients with active symptomatic treatment-naive VKC. All patients were treated with the 0.03% tacrolimus ophthalmic ointment twice daily for 2 months and then once daily for 1 month. All patients underwent AS-OCT before and 3 months after treatment as an objective method to assess the treatment efficacy.
Results: We included 20 eyes of ten patients (nine men and one woman) with active symptomatic treatment-naive VKC. The mean age was 17.3 (range: 11–36) years, with nine patients having a palpebral type and one patient having a mixed type of VKC. Substantial flattening and reduction in the papilla size were observed in all patients at the post-treatment follow-up. AS-OCT measurements revealed significant reductions in the vertical, horizontal, and total diameters of the palpebral papillae and limbal conjunctival thickness after 3 months of treatment compared to baseline measurements (all P < 0.001). No serious adverse effects attributable to tacrolimus administration were observed in the study period.
Conclusions: AS-OCT is a suitable objective method for evaluating the treatment efficacy of the 0.03% tacrolimus eye ointment in patients with VKC. Future large-scale studies including a wide range of age groups with longer follow-up periods and AS-OCT monitoring at multiple post-treatment visits are required to confirm our preliminary results. Moreover, the diagnostic accuracy of AS-OCT in monitoring patients with active VKC should be tested in comparison with objective scoring by an experienced corneal fellowship.

Background: Vortex keratopathy is a corneal entity characterized by corneal deposits at the level of the basal epithelium in the form of a whorl-like pattern in the interpalpebral portions of the cornea. Medications such as amiodarone, chloroquine, hydroxychloroquine, indomethacin, phenothiazines, ibuprofen, and naproxen bind to the cellular lipids of the basal epithelial layer of the cornea, producing a characteristic whorl pattern. Here, we report a case of bilateral central vortex keratopathy with slight vision impairment 3 weeks after uneventful photorefractive keratectomy (PRK) in a woman on long-term clozapine treatment.  
Case Presentation: A 42-year-old woman presented to the outpatient clinic for refractive surgery for the correction of bilateral moderate myopia. Her best-corrected distance visual acuity was 20/20 in both eyes. She had been on antipsychotic clozapine tablets 400 mg/day for the past 6 years to manage a psychiatric disorder. On detailed preoperative slit-lamp examination, her corneas were clear, with perilimbal conjunctival pigmentations. Other ocular examination results were unremarkable. At the 3-week follow-up after an uneventful PRK, her uncorrected distance visual acuity was 20/25 in the right eye and 20/20 in the left eye, with complaints of slightly unclear vision in both eyes. Slit-lamp examination revealed bilateral corneal subepithelial deposits in a whorl-like pattern reminiscent of vortex keratopathy. The deposits were restricted to the epithelial and subepithelial regions and did not extend to the stroma without evident stromal haze. Dilated fundus examination results were normal bilaterally. Despite excellent refractive outcomes and visual acuity in both eyes, she was dissatisfied and complained of unclear vision. She was administered with lubricating eye drops and placed on regular follow-ups. At the 4-month follow-up, the vortex lines were cleared centrally, and she reported improvement in vision. Anterior-segment optical coherence tomography of the cornea revealed no epithelial deposits in the central part of the cornea and residual deposits in the temporal peripheral cornea, indicating clearing of the deposits from the central cornea and explaining the subjective improvement in vision. Her final best-corrected distance visual acuity was 20/20 in both eyes with an unremarkable ocular examination.
Conclusions: Our case indicates a potential causal relationship between long-term clozapine treatment and development of temporary, visually significant vortex keratopathy after uneventful PRK. Further large-scale studies are required to verify the causal relationship between the long-term clozapine administration and the development of vortex keratopathy following surface ablation photorefractive procedures.

Letter to the Editor
Note: letters have no abstract.