Marcos Jacob Cohen

Mansonella ozzardi corneal lesions in the Amazon: a cross-sectional study

Objectives To characterise and confirm the presence of Mansonella ozzardi microfilariae in the cornea by biomicroscopy and corneal confocal microscopy. Design Cross-sectional study. Settings Clinical practice study in patients from rural communities in Coari city on the Solimões river, Amazonas state, Brazil. Participants The eyes of 212 consecutive volunteer patients were examined using a flash light and their blood checked for the presence of microfilariae by an expert microscopist. Patients with suspicious corneal lesions (characterised as nummular keratitis) were submitted to biomicroscopy, fundoscopy and corneal confocal microscopy evaluation (CCME). In two patients, a biopsy of the limbal conjunctiva adjacent to the nummular keratitis was carried out and blood collected from the surgical wound for microfilariae investigation by thick blood film examination. Primary and secondary outcome measures Positive correlation between corneal biomicroscopic and confocal lesions and M ozzardi microfilaremia. Results Of the 212 patients, 56 (26.4%) were positive for microfilaremia. 22 patients with nummular keratitis identified under flash light examination underwent biomicroscopy and CCME. Corneal lesions were positively correlated to microfilaremia (p=0.0001). At biomicroscopy, lesions were classified as quiescent or active. At CCME, lesions were categorised as circular or filiform. The associations between corneal lesions, CCME findings and microfilaremia are shown. Conclusions We describe M ozzardi microfilariae in the cornea and the associated eye pathology. Further studies using ocular tissue PCR and other imaging techniques would be helpful.

Efficacy of a lutein-based dye (PhacodyneTM) for visualizing anterior capsulorhexis during cataract surgery by phacoemulsification

PURPOSE To evaluate the efficacy and safety of a novel lutein-based dye for the anterior capsulorhexis during phacoemulsification in cataract surgery in humans. METHODS Twenty-five eyes from 25 patients were operated by 25 different surgeons who performed continuous circular capsulorhexis (CCC) guided by a lutein-based dye (Phacodyne™) during cataract surgery by phacoemulsification. A questionnaire assessed the surgeon’s opinion regarding the efficacy of the dye. Follow-up examinations were performed at 1, 7, and 30 days post-surgery. Eyes were evaluated by full ophthalmic examination, corneal topography/pachymetry, and corneal endothelial cell count. RESULTS As revealed by the answers to the questionnaire, the dye facilitated the CCC procedure in all eyes. Baseline nuclear cataract classification (according to the Lens Opacities Classification System III; LOCS III) was 3.24 (± 1.12). Preoperative BCVA (logMAR) was 0.89 ± 0.59 and improved to 0.23 ± 0.22 on day 30 after surgery. The intraocular pressure (IOP) remained stable and the inflammatory reaction subsided in all cases within the first 7 days after surgery. The pre-operative values of corneal pachymetry and IOP were similar to those found on follow-up day 30. Loss in endothelial cell number was similar to earlier reports. CONCLUSION Phacodyne™ was efficient when used for anterior capsulorhexis during cataract surgery by phacoemulsification and

Vision Status in Older Adults: The Brazilian Amazon Region Eye Survey

Older adults living in remote areas with limited access to health services are at higher risk to develop visual impairment and blindness. We conducted a population-based survey to determine the vision status in subjects 45 years of age and older from urban and rural areas of Parintins city, Brazilian Amazon Region. Participants underwent ophthalmic examination, including uncorrected (UCVA), presenting (PVA) and best-corrected visual acuity (BCVA). Vision status was described as lines of visual acuity (VA) impairment and lines of VA improvement from UCVA to BCVA and from PVA to BCVA in the better-seeing eye. A total of 2384 subjects were enumerated, 2041 (85.6%) were examined, with reliable VA measurements obtained from 2025 participants. Vision status in lines of VA impairment was (mean ± standard deviation): 3.44 ± 3.53 for UCVA, 2.85 ± 3.52 for PVA and 1.50 ± 3.51 for BCVA. Female gender, older age and lower education were associated with ≥6 lines of UCVA impairment. Lines of improvement ≥3 was found in 626 (30.9%) participants and associated with female gender and rural residency. In conclusion, a third of participants could have at least three lines of VA improvement with proper refraction. Strategies to improve access to eye care and affordable glasses are needed.

Presbyopia and Ocular Conditions Causing Near Vision Impairment in Older Adults From the Brazilian Amazon Region

PURPOSE To investigate the prevalence and causes of near vision impairment (NVI) in a population of older adults from the Brazilian Amazon Region. DESIGN Population-based cross-sectional study. METHODS Cluster sampling was used in randomly selecting subjects 45 years of age and older from urban and rural areas of Parintins city, Brazil. Participants underwent ophthalmic examination, including uncorrected (UCNVA), presenting (PNVA), and best-corrected near visual acuity (BCNVA) from each eye; biomicroscopy; funduscopy; and subjective refraction, including testing with additional lenses for near vision optical correction. A principal cause for NVI was assigned by the ophthalmologist and presbyopia was defined as UCNVA ≤ 20/40 changing to > 20/40 with BCNVA. Free-of-charge glasses were provided for those in need. RESULTS A total of 2384 subjects were enumerated and 2025 had reliable NVA measurements from both eyes. The prevalence of NVI in the better-seeing eye was 96.5% with UCNVA, decreasing to 81.1% with PNVA and to 20.5% with BCNVA. Presbyopia was the principal cause of NVI in 71.8%, followed by cataract (16.5%) and pterygium (2.5%), and was associated with younger age and high schooling. Glasses for near vision were prescribed and provided to 1414 (69.8%) participants. CONCLUSIONS A high prevalence of NVI was detected even in those wearing glasses for near. Prescription and provision of low-cost reading glasses should be considered by Brazilian health authorities to address this easily and promptly correctable form of vision impairment.