Short-term visual performance of soft multifocal contact lenses for presbyopia / Desempenho visual de curto prazo de présbitas usando diferentes lentes de contato multifocais hidrofílicas

ABSTRACT Purpose: To compare visual acuity (VA), contrast sensitivity, stereopsis, and subjective visual performance of Acuvue® Oasys® for Presbyopia (AOP), Air Optix® Aqua Multifocal (AOMF), and Air Optix® Aqua Single Vision (AOSV) lenses in patients with presbyopia. Methods: A single-blinded crossover trial was conducted. Twenty patients with mild presbyopia (add ≤+1.25 D) and 22 with moderate/severe presbyopia (add ≥+1.50 D) who wore lenses bilaterally for 1 h, with a minimum overnight washout period between the use of each lens. Measurements included high- and low-contrast visual acuity (HCVA and LCVA, respectively) at a distance, contrast sensitivity (CS) at a distance, HCVA at intermediate (70 cm) and near (50 cm & 40 cm) distances, stereopsis, and subjective questionnaires regarding vision clarity, ghosting, overall vision satisfaction, and comfort. The test variables were compared among the lens types using repeated-measures ANOVA. Results: Distance variables (HCVA, LCVA, and CS) were significantly worse with multifocal lens than with AOSV lens (p≤0.008), except for AOMF lens in the mild presbyopia group in which no significant difference was observed (p>0.05). Multifocal lenses had significantly greater HCVA at 40 cm than AOSV lens (p≤0.026). AOMF lens had greater intermediate HCVA than AOP lens (p<0.03). AOP lens demonstrated greater improvements in stereopsis than AOMF and AOSV lens in the moderate/severe presbyopia group (p≤0.03). Few significant differences in subjective variables were observed, with no significant difference in the overall vision satisfaction observed between lens types (p>0.05). The proportions of patients willing to buy AOSV, AOMF, and AOP lenses were 20%, 40%, and 50%, respectively, in the mild presbyopia group and 14%, 32%, and 23%, respectively, in the moderate/severe presbyopia group; however, these differences were not statistically significant (p≥0.159). Conclusions: Further development of multifocal lenses is required before significant advantages of multifocal lenses over single vision lens are observed in patients with presbyopia.

RESUMO Objetivo: Comparar a acuidade visual, sensibilidade ao contraste, estereopsia e desempenho visual subjetivo de présbitas usando lentes de contato Acuvue Oasys para presbiopia (AOP), Air Optix Aqua Multifocal (AOMF) e Air Optix Aqua Single Vision (AOSV). Método: Foi realizado estudo mascarado simples, cruzado. Vinte pacientes com presbiopia baixa (adição ≤+1,25 D) e 22 com presbiopia média/alta (adição ≥+1,50 D) usaram cada lente bilateralmente durante 1 hora, com descanso mínimo de uma noite entre as diferentes lentes. As medições incluíram acuidade visual para distância em alto e baixo contraste (HCVA, LCVA), sensibilidade ao contraste para distância (CS), HCVA para distância intermediária (70 cm) e para perto (50 cm e 40 cm), estereopsia e questionários subjetivos sobre nitidez visual, fantasmas, satisfação visão geral e conforto. As variáveis foram comparadas entre os tipos de lentes, utilizando medidas repetidas ANOVA. Resultados: As variáveis para distância (HCVA, LCVA, CS) foram significativamente piores com as multifocais em relação a AOSV (p≤0,008), exceto para AOMF no grupo de baixa adição, que não foi significativamente diferente (p>0,05). As multifocais foram significativamente melhores do que a AOSV para HCVA em 40 cm (p≤0,026). AOMF superou AOP para HCVA intermediária (p<0,03). AOP superou AOMF e AOSV em relação à estereopsia no grupo de presbiopia médio/alto (p≤0,03). Houve poucas diferenças significativas nas variáveis subjetivas, mas a satisfação visual global não foi significativamente diferente entre as lentes (p>0,05). A disposição para comprar lentes AOSV, AOMF e AOP foi: 20%, 40%, 50%, respectivamente, no grupo de presbiopia baixa; 14%, 32%, 23% no grupo de presbiopia média/alto, mas essas diferenças não foram estatisticamente significativas (p≥0,159). Conclusões: Melhorias futuras parecem ser necessárias para produção de uma lente multifocal que forneça aos présbitas uma vantagem significativa sobre a lente de visão única.

Spectacle compliance amongst rural secondary school children in Pune district, India.

Background: Refractive errors (RE) are the most common cause of avoidable visual impairment in children. But benefits of visual aids, which are means for correcting RE, depend on the compliance of visual aids by end users. Aim: To study the compliance of spectacle wear among rural school children in Pune district as part of the sarva siksha abhiyan (education for all scheme) after 6 - 12 months of providing free spectacles. Settings and Design: Cross-sectional follow-up study of rural secondary school children in western India. Materials and Methods: The students were examined by a team of optometrists who collected the demographic details, observed if the child was wearing the spectacles, and performed an ocular examination. The students were asked to give reasons for non-wear in a closed-ended questionnaire. Statistical Analysis: Chi-square test and multiple logistic regression used for data analysis. Results: Of the 2312 students who were dispensed spectacles in 2009, 1018 were re-examined in 2010. 523 students (51.4%) were female, the mean age was 12.1 years 300 (29.5%) were wearing their spectacles, 492 (68.5%) students claimed to have them at home while 211 (29.4%) reported not having them at all. Compliance of spectacle wear was positively associated to the magnitude of refractive error (P < 0.001), father's education (P = 0.016), female sex (P = 0.029) and negatively associated to the visual acuity of the better eye (P < 0.001) and area of residence (P < 0.0001). Of those that were examined and found to be myopic (N = 499), 220 (44%) wore their spectacles to examination. Factors associated with compliance to spectacle usage in the myopic population included increasing refractive error (P < 0.001), worsening visual acuity (P < 0.001), and higher academic performance (P < 0.001). The causes for not wearing spectacles were ‘lost spectacles’ 67(9.3%), ‘broken spectacles’ 125 (17.4%), ‘forgot spectacles at home’ 117 (16.3%), ‘uses spectacles sometimes’ 109 (15.2%), ‘teased about spectacles’ 142 (19.8%) and ‘do not like the spectacles’ 86 (12%). Conclusion: Spectacle compliance was poor amongst school children in rural Pune; many having significant vision loss as a result.

Key factors determining success of primary eye care through vision centres in rural India: Patients’ perspectives.

Aim: This paper intends to discuss the patients’ perspective on the determinants of primary eye care services from vision centers (VC) in rural India. Materials and Methods: A retrospective study design and interview method was used on 127 randomly selected patients who accessed the 4 VCs in 2007. Factor analyses and linear regression models were used to predict the associations with patient satisfaction. Results: The three factors derived from factor analyses were: (1)-vision technician (VT), (2)-location of VC, and (3)-access to VC; explaining 60% of the variance in total patients’ satisfaction with VC. The first model (R2: 0.61; F1,124=144.36, P<0.001), indicated that respondents who had ‘difficulty to travel to the place of VC’ and those who can afford to pay had less satisfaction with VT services. The second model (R2=0.18; F1,124=29.5, P<0.001) explained that respondents’ difficulty to identify the building of VC had decreased patients’ satisfaction and the third model (R2=0.36; F1,124=45.6, P<0.001) indicated that those who had to travel<5 km to the VC and had 0.38 units of increased satisfaction level with the services of VC. Conclusion: A good VT can enhance patient satisfaction. However, patient expectations are not only confined to the provider but also other factors such as ability to pay and convenient transportation that helps patients reach the location of the VC with ease.

The role of optometrists in India: An integral part of an eye health team.

India has a proud tradition of blindness prevention, being the first country in the world to implement a blindness control programme which focused on a model to address blinding eye disease. However, with 133 million people blind or vision impaired due to the lack of an eye examination and provision of an appropriate pair of spectacles, it is imperative to establish a cadre of eye care professionals to work in conjunction with ophthalmologists to deliver comprehensive eye care. The integration of highly educated four year trained optometrists into primary health services is a practical means of correcting refractive error and detecting ocular disease, enabling co-managed care between ophthalmologists and optometrists. At present, the training of optometrists varies from two year trained ophthalmic assistants/optometrists or refractionists to four year degree trained optometrists. The profession of optometry in India is not regulated, integrated into the health care system or recognised by the majority of people in India as provider of comprehensive eye care services. In the last two years, the profession of optometry in India is beginning to take the necessary steps to gain recognition and regulation to become an independent primary health care profession. The formation of the Indian Optometry Federation as the single peak body of optometry in India and the soon to be established Optometry Council of India are key organisations working towards the development and regulation of optometry.

Expressions of equity: imbalances in the patient-clinician interaction.

This paper reports patient perceptions of inequities in the doctor-patient interaction. A mixed method study was conducted in a tertiary eye care centre in southern India to gain an insight into patient understanding and satisfaction from clinician communication. Non-participant observations enabled us to map the sequence of communication opportunities in the clinical interaction, and in-depth interviews were used to identify patient perceptions of the content and clarity of clinician communication in a clinic for patients of glaucoma, a chronic eye disease. A 60-item instrument was administered to 550 participants in the quantitative phase to explore associations between patient expectations, experience and ratings of clinician communication and satisfaction with it.

Comparison of patient satisfaction with services of Vision Centers in rural areas of Andhra Pradesh, India.

Aim: To compare the satisfaction of patients with the services of Vision Center services (primary eye care) in large village (s) and small village (s) in rural settings in Andhra Pradesh state, India. Materials and Methods: We have administered standard questionnaires to randomly selected patients to assess patient satisfaction when assessing Vision Center Services. We used the Chi-square (P <0.05) to explore differences in satisfaction of patients with Vision Center services located in the large village (s) and small village (s) rural settings. Results: Vision Center patients at the large village (s) expressed higher levels of satisfaction (median 78%) than patients treated at the Vision Center at small village (s) (median 69%). The difference was statistically significant (Chi square P value ranging from <0.001 to 0.03) for all the items except two – ‘easy to identify vision center location’ and ‘spectacles dispensing time’ as compared to other (privately run optometry) facilities (Chi square P value=0.498 and 0.993 respectively). The location of the Vision Center, convenience of journey, ophthalmic technician’s behavior with patients, are some of the most important factors that determined the patient perception about Vision Center services. Conclusion: The overall satisfaction levels of the Vision Center experience at 78% and 69% were good. However, continual improvement is to be made in service time, staff performance, cost and quality of vision care, especially at more remote primary eye Care Centers.