Revista Cubana de Oftalmología (Dec 2004)
Personalización de las fórmulas de cálculo de lente intraocular Personalization of the intraocular lens calculation formulas
Abstract
Este trabajo tiene la finalidad de evaluar los resultados refractivos que se alcanzan con la introducción de las constantes personalizadas en las fórmulas de tercera generación para el cálculo del lente intraocular. Se realizó un estudio descriptivo prospectivo cuyo universo está constituido por los pacientes con catarata senil y se seleccionó una muestra aleatoria de 597 casos. Los pacientes fueron clasificados en 7 grupos según las mediciones preoperatorios del promedio queratométrico y la longitud axial. Para dar salida al objetivo propuesto fueron utilizadas las siguientes variables: longitud axial, promedio queratométrico, componente esférico esperado (sep), componente esférico obtenido (ceo), dioptría de lente intraocular implantado (This paper is aimed at evaluating the refractive results attained with the introduction of personalized constants in the third generation formulas for the intraocular lens calculation. A descriptive and prospective study was conducted among the patients with senile cataract, and a randomized sample of 597 cases was selected. Patients were classified into 7 groups according to the preoperative measurements of the keratometric average and the axial longitude. To obtain the proposed objective, the following variables were used: axial longitude, keratometric average, expected spherical component (sep), obtained spherical component (ceo), dioptry of implanted ocular lens (<16, of 17-19, 20-23, 24-27, 28-30) and refractive results. The statistical analysis of the results was made by a varianze analysis, the T test of comparison of means for matched data and Ji square. A confidence level of 95.5 was used. The utilization of personalized constants in the calculation of intraocular lens increased by more than 20 % the good refractive results. No differences were observed in the diverse groups of patients, the type of formula used and the dioptric power of the lens.The S3652 and S3602 lens models presented a high percentage of hypocorrection. The visual acuity attained in all cases was over 0.5, a result that is comparable with that of recent international studies. The preoperatively estimated corresponded to the real postoperative value, which evidences an adequate effective position of the lens.