Outdoor activity and myopia progression in children: A follow-up study using mixed-effects model.

PURPOSE: The purpose of this study was to determine the influence of outdoor activity on myopia progression. METHODS: It was a hospital-based longitudinal prospective observational study. Children between 7 and 14 years of age with a myopia of - 0.5 D or worse were included. Myopia progression was evaluated by cycloplegic refraction, every 6 months for 18 months. Parents were asked to record the daily outdoor activity of the child in hours per day at school and at home during weekdays and at weekends separately, based on which the daily outdoor activity score was calculated. The independent variables measured included age and gender of the participant, degree of myopia, and the daily outdoor activity score. Progression of myopia was defined as an increase in the spherical equivalent (SE) over 18 months. The magnitude of the association was determined by two mixed-effects models. RESULTS: A total of 495 participants (250 males and 245 females) completed three visits during the study period. On taking age groups and paired observations as a random effect and adding SE at the last visit as the random slope in Model 1, each unit increase in outdoor activity had a negative effect on change in SE of - 0.01 (-0.02 to 0.00; P = 0.045). The same inverse relationship between outdoor activity and absolute SE as - 0.06 (-0.07 to - 0.03; P < 0.001) is estimated in Model 2. CONCLUSION: The study demonstrates a statistically significant inverse relationship between outdoor activity and myopia.

Impact of corneal refractive surgery on the precorneal tear film.

Corneal refractive surgeries are one of the commonly performed procedures for correction of refractive errors. Tear film abnormality is the most common postoperative complication of corneal refractive surgeries. Consequently, these procedures represent a clinically significant cause of dry eye disease. The mechanisms which lead to dry eye disease include corneal sensory nerve dysfunction, ocular surface desiccation, glandular apoptosis and ocular surface inflammation. Although transient tear film abnormalities occur in almost all patients following surgery, patients with pre-existing dry eye symptoms or dry eye disease are at significant risk of developing more severe or long-term ocular surface disease. As such, careful patient selection and preoperative evaluation is essential to ensuring successful surgical outcomes. This is particularly important with LASIK which has the strongest association with dry eye disease. Appropriate surface lubrication and anti-inflammatory therapy remains the cornerstone treatment. Timely and effective management is important to facilitate visual rehabilitation and reduce the risk of secondary complications. In this review we describe the causes, pathophysiology, risk factors, manifestations, and management of tear film dysfunction and dry eye disease following corneal refractive surgery.

A case of occult bilateral optic nerve aplasia with pituitary dysfunction: hidden anomaly missed on ultrasound.

We report a case of 'occult' bilateral optic nerve aplasia (ONA) where pituitary dysfunction was discovered subsequently. The initial ultrasonography had missed ONA in a child with bilateral microcornea, small non-dilating pupils and roving eye movements. Due to presence of relevant clinical signs in this case, ONA was re-evaluated with MRI, and was subsequently discovered to be associated with life-endangering hypopituitarism. This case raises the possible underestimation of ONA, and hence also the risk of missing life-threatening endocrine disorders.

Autoimmune thyroiditis and central serous chorioretinopathy may have a relation.

Autoimmune thyroiditis (AT) is an important cause of hypothyroidism, and central serous chorioretinopathy (CSCR) is an independent disease of the choroid and retina that leads to accumulation of fluid beneath the retina. While AT has been associated with multiple antibodies, CSCR is still regarded as idiopathic despite extensive research. We hypothesize a causative association between these 2 conditions on the basis of our experience of a case where both CSCR and AT presented simultaneously and depicted a parallel course. CSCR was documented with retinal imaging while AT was documented with serum antibody titers. Further, we discuss the possible mechanisms that may be involved in this intriguing association.