The risk of vision loss in contact lens wear and following LASIK.

PURPOSE: To compare the risk of vision loss following contemporary laser-assisted in situ keratomileusis (LASIK) with different types and modality of use of contact lenses. METHODS: Data from a previously published study were used to derive the incidence of vision loss (≥ 2 line loss of best corrected spectacle acuity) following microbial keratitis for different contact lens types and wearing modality, stratified by duration of lens wear. A literature search on vision loss following LASIK was performed between 2003 and 2019. The prevalence of vision loss at six months post-surgery was captured from clinical trials published after 2003. A proportion meta-analysis was applied to derive the prevalence of vision loss following LASIK. A least-squares fitting of cumulative vision loss (P, /10 000 wearers) over time (t, years) using an exponential model estimated the years of contact lens wear to which the risk of vision loss with LASIK was equivalent. RESULTS: Vision loss following LASIK occurred in 66 (95% confidence interval [CI] 34-108) per 10 000 wearers. As a conservative estimate based on the lower confidence interval of the estimated equivalent years of contact lens wear, daily wear contact lenses and extended overnight silicone wear hydrogel contact lens need to be worn for 103 (95% [CI] 103-391) and 25 (95% [CI] 25-79) years respectively, to equal the rate of vision loss equivalent to a one-off LASIK procedure. CONCLUSIONS: The risk of vision loss to the individual is low with either contact lens wear or refractive surgery. Contact lens wear does not pose a higher risk of vision loss than LASIK surgery for the most common wear modalities.

Adeno-associated virus neutralising antibodies in type 1 diabetes mellitus.

Recombinant Adeno-associated viruses (AAVs) are an attractive vector for gene therapy delivery which may be blocked by AAV neutralising antibodies (NAbs). As Type 1 Diabetes (T1DM) is an endocrine disease of immunological origin, it is likely that NAb profiles are altered in the disease. In this study NAb to AAV2, AAV5, AAV6, and AAV8 in 72 subjects with T1DM and 45 non-diabetic patients were measured over a 4-year follow-up period. AAV2 NAb titres were significantly lower in non-diabetic subjects (P = 0.036). The T1DM group had more AAV8 NAb activity at baseline (P = 0.019), whilst after 4 years follow-up the T1DM group displayed developed increased AAV 5 (P = 0.03), 6 (P = 0.03) and 8 (P = 0.002) activity relative to the control group, however, overall AAV5 and 8 NAb levels were very low in patients <40. AAV NAb titre activity and prevalence generally appears higher in T1DM, however, low levels of AAV 5 and 8, particular in younger adult age groups at which T1DM can be targeted, could make these attractive vectors to target the disease.

Relationship between climate, disease severity, and causative organism for contact lens-associated microbial keratitis in Australia.

PURPOSE: To evaluate associations between disease severity, causative organism, and climatic variation in contact lens-related microbial keratitis in Australia. DESIGN: Prospective, observational case series. METHODS: Contact lens wearing patients (n = 236) with presumed microbial keratitis presenting to private and hospital ophthalmologists in Australia between October 1, 2003 and September 30, 2004 were identified prospectively. Clinical details, management information, and microbiology data were collected and cases were graded for severity based on lesion size and location criteria. Causative organisms were assigned to "environmental" or "endogenous" groups. Climate zone and daytime temperature and humidity were determined for the geographic location of each event. The main outcome measures were disease severity, causative organism, and climate zone. RESULTS: Severe contact lens-related microbial keratitis was more likely to occur in warmer, humid regions of the country (P < .001), compared with smaller, increasingly peripheral corneal lesions that were more common in cooler conditions (P < .001). Culture-proven keratitis was predominantly caused by environmental organisms with Pseudomonas aeruginosa being recovered most frequently. Environmental organisms were isolated more commonly from tropical regions of the country and also accounted for nearly all cases of vision loss that occurred during the study period. Humidity did not have a significant effect on causative organism. CONCLUSIONS: Climatic conditions play a role in disease severity and causative organism in contact lens-related microbial keratitis and therefore have implications for practitioners involved in contact lens care and contact lens wearers who live in or travel to the tropics.