Health Spain , Valladolid, Wednesday, April 17 of 2013, 12:51

Cataract surgery upgrading

According to estimates, 400,000 cataract operations are performed every year in Spain

Cristina G. Pedraz/DICYT Cataract surgery is the most common surgery in ophthalmology. According to estimates, 400,000 operations are performed every year in Spain. Cataract surgery is the removal of the natural lens of the eye that has develop an opafication (which causes vision loss), then, an artificial lens is implanted allowing to restore vision. Researchers from the Instituto de Oftalmología Aplicada (IOBA), an institute of applied ophthalmology in Valladolid, Spain, have studied the refractive state of patients after cataract surgery is performed in order to optimize operation’s end results.

This study is part of the doctoral thesis by Victoria de Juan, an optician-optometrist and IOBA researcher, mentored by ophthalmologist José María Herrera Cantalapiedra. De Juan presented the study (carried out for the last four years) in January 2013 in a research seminar in this institute.

“We have studied fundamentals of refraction after cataract surgery is performed, such as refractive stability, analyzing it with different methods. We have also validated several instruments and have studied whether the instrument used to measure lens strength affects refraction, and to what extent.”, as the researcher summarized to DiCYT.

Their major aim is to “upgrade end results of cataract surgery”, the most common in ophthalmology and “the most required in order to avoid wearing glasses”. This is generally ensured when eyes are “relatively normal”, but problems arise when the axial length of the eye “is too big or too small”.

The dissertation was defended on March and was carried out in various stages. In 2008, funding was granted by the Fondos de Investigaciones Sanitarias (FIS), a health research fund from the Instituto de Salud Carlos III. In 2009 and 2010, patients were taken on to the study (210 patients). After this, results were analyzed and the first publications were developed.


The research was focused on two instruments used to measure the intraocular lens (the artificial lens replacing the natural lens and allowing to restore vision): ultrasound biometry (UB) and optical biometry (OB).

According to findings, eyes with a big or a small axial length, that is, “very near or far-sighted patients”, have a worse outcome in cataract surgery. Although this fact was already known, researchers have proved that “outcomes can be better” if OB is used.

This finding is very important because “a guideline can be made indicating the right instrument depending on the axial length or any other eye feature, so outcomes may improve”, the researcher states.