Purpose: To analyze and compare the mid-term objective and subjective performance of two phakic intraocular lenses (PIOLs) - Visian® ICL™ V4c and Artiflex® and to correlate those results with anatomical parameters. Patients and methods: Observational retrospective study including thirty patients (15 for each PIOL) randomly selected from those who underwent bilateral implantation of one of the PIOLs (60 eyes were analysed). Uncorrected and corrected distance visual acuities (UDVA and CDVA), anterior chamber structural parameters, and corneal endothelial cells density and morphology were evaluated. Quality of vision was assessed both subjectively with a questionnaire, and objectively using a double-pass technology optical quality analysis system. Results: At the end of follow-up the Artiflex® group showed better UDVA (0.95±0.11 vs 0.99±0.05, p=0.027) and higher proportion of eyes reaching at least 20/20 (28/30 vs 18/30, p=0.005). Excellent and similar objective scatter index (1.79±0.9 vs 2.14±1.6, p=0.306) and modular transfer function cutoff frequency (26.91±9.2 vs 26.51±11.9, p=0.784) results were achieved in the HD Analyzer® and the questionnaire showed comparable high Satisfaction (55.7±3.5 vs 54.3±5.4, p=0.386) and low Dysphotopsia Scores (3.1±1.8 vs 2.1±2.2, p=0.213). The ICL group showed inferior anterior chamber volume (p<0.001), and angle (p<0.001) and superior pupillary diameter (p=0.007). Minimum follow-up was 24 months. Conclusion: Both the Visian® ICLV4c™ and the Artiflex® showed excellent optical performance through the HD AnalyzerTM technology, translated in high patient satisfaction. Overall, both PIOLs showed similar safety, predictability, stability and effectiveness of for the reduction of high sphero-cylindrical refractive errors, despite better UDVA results with the Artiflex®.

PURPOSE: The purpose of this study was to evaluate the visual and refractive outcomes and rotational stability of the new aspheric Precizon(®) toric intraocular lens (IOL) for the correction of corneal astigmatism in cataract surgery. SETTING: Department of Ophthalmology, Hospital Geral de Santo António - Centro Hospitalar do Porto, EPE and Hospital de Pedro Hispano, Matosinhos, Portugal. DESIGN: This was a prospective clinical study. PATIENTS AND METHODS: A total of 40 eyes of 27 patients with corneal astigmatism greater than 1.0 diopter (D) underwent cataract surgery with implantation of Precizon(®) toric IOL. IOL power calculation was performed using optical coherence biometry (IOLMaster(®)). Outcomes of uncorrected (UDVA) and best-spectacle corrected distance visual acuities (BCDVA), refraction, and IOL rotation were analyzed at the 1st week, 1st, 3rd, and 6th month's evaluations. RESULTS: The median postoperative UDVA was better than preoperative best-spectacle corrected distance visual acuity (0.02 [0.06] logMAR vs 0.19 [0.20] logMAR, P<0.001). At 6 months, postoperative UDVA was 0.1 logMAR or better in 95% of the eyes. At last follow-up, the mean spherical equivalent was reduced from -3.35±3.10 D to -0.02±0.30 D (P<0.001) with 97.5% of the eyes within ±0.50 D of emmetropia. The mean preoperative keratometric cylinder was 2.34±0.95 D and the mean postoperative refractive cylinder was 0.24±0.27 D (P<0.001). The mean IOL rotation was 2.43°±1.55°. None of the IOLs required realignment. CONCLUSION: Precizon(®) toric IOL revealed very good rotational stability and performance regarding predictability, efficacy, and safety in the correction of preexisting regular corneal astigmatism associated with cataract surgery.

Purpose: To describe the anatomical and functional results of the implantation of asymmetric thickness intracorneal ring segments (AS-ICRS) in eyes with keratoconus and asymmetric/irregular astigmatism (type 2 - Duck - and type 3 - Snowman - phenotypes, Fernandez-Vega/Alfonso morphologic Keratoconus classification). Materials and methods: Retrospective observational study including 19 consecutive patients (21 eyes) with keratoconus who underwent manual implantation of the Keraring® Asymmetric ICRS (AS). Analysis included demographic and clinical data and Pentacam (Oculus®) measurements: topographic astigmatism; topographic flat meridian (K1), steepest meridian (K2) and the maximum keratometric point (Kmax); total root mean square (RMS) and high order RMS (HOA) aberrations and comatic Zernike coefficients (Z31;Z3-1) at 0º and 90º meridians. Results: Overall mean age was 35.3±11.7 years and median follow-up was 7.1 months (range 6-12). At the end of follow-up, a significant improvement from baseline was achieved in both UDVA (0.24±0.22; p=0.017) and CDVA (0.21±0.17; p<0.001). Regarding topographic measurements, the greatest decrease was observed in K2 (2.76±1.9D; p<0.001) and astigmatism (1.97±1.5; p<0.001). Aberrometry analysis showed a reduction of 1.27±3.2µm in the total RMS (p=0.085), 0.24±0.9µm in HOA (p=0.227) and 0.78±0.5 (p<0.001) in the 90º component of comatic aberration. The procedure effects in the CDVA, topographic and aberrometric parameters were higher in type 2 cones without statistical significance (p>0.05 in all). Conclusion: Implantation of the Keraring® Asymmetric ICRS in keratoconus with asymmetric/irregular astigmatism allowed an improvement of several clinical, topographic and aberrometric parameters, with clinical efficacy and safety, with a tendency to a greater effect in the type 2 cones.

RESUMO - Prevalência dos erros refrativos na área de Lisboa numa população infantil: Um Estudo Piloto. Objetivo: Determinar a prevalência dos erros refrativos numa população dos 6 aos 12 anos em Lisboa. Analisar a exposição a fatores de risco e avaliar a sua correlação com a prevalência dos erros refrativos. Analisar os fatores de prevenção de erros refrativos e verificar se existe correlação com os erros refrativos. Métodos: Trata-se de um estudo observacional prospetivo transversal e multicêntrico, a recolha de dados foi feita em 5 escolas da área de Lisboa de outubro a dezembro de 2021, realizada pelo núcleo de investigação Optovisão do Instituto Superior de Educação e Ciências de Lisboa (ISEC Lisboa). Participaram neste estudo 252 crianças, de idades compreendidas entre s 6 e os 12 anos. Resultados: A idade média dos participantes foi de 8,0±1.5 anos e a mediana foi de 8 anos. A prevalência da miopia foi de 9,5% (n=22), a de emetropia 34,1% (n=86) e a de hipermetropia 56,3% (n=144). Entre os 6 e os 11 anos, a taxa de hipermetropia diminuiu e a miopia aumentou 12,5%. De todos os participantes com miopia, 81% (n=17) tinham baixa miopia e 19% miopia moderada. Em relação à idade, existe una clara tendência à miopização com o passar dos anos. Dentro do intervalo de tempo em visão próxima 36,9% dos participantes passavam menos de 25% do tempo em dispositivos digitais, 45,4% entre 25%-50% e 17,6% passavam mais de 50% do tempo. Não se encontrou uma associação entre o tempo de uso dos dispositivos digitais com a idade, género e estado refrativo. Conclusões: Podemos concluir com este estudo que houve um aumento da miopia com a idade e que o erro refrativo com maior prevalência foi a miopia. Dentro deste grupo, a miopia baixa é a mais comum. Não se verificaram aumentos nas atividades em visão próxima associados à idade ou género nem se encontrou uma associação entre o género e o tempo passado em dispositivos digitais e o erro refrativo apresentado. Foi possível verificar o fator hereditário da miopia uma vez que se encontrou uma relação entre a sua presença em um ou ambos os progenitores. Não se verificou uma associação entre o tempo de exposição à luz ultravioleta e a idade.