Comparative study of induced changes in effective lens position and refraction after Nd:YAG laser capsulotomy
Tiago Monteiro1,2, Andreia Soares1, Ricardo Dourado Leite1
1Department of Ophthalmology, Hospital de Braga, Braga, Portugal.
Purpose:
To evaluate and compare the changes in refraction and effective intraocular lens (IOL) position between a plate-haptic IOL and a c-loop single-piece IOL after neodymium-doped yttrium aluminium garnet (YAG) laser posterior capsulotomy.
Methods:
In a prospective study, anterior chamber depth and subjective refraction were measured in 110 pseudophakic eyes from 110 patients, before and 1 month after YAG laser capsulotomy. Patients were divided into 2 groups according to the IOL design: group 1 (plate-haptic acrylic hydrophilic AT LISA tri 839MP®) and group 2 (c-loop acrylic hydrophobic single-piece AcrySof® SA60AT). Lens position was obtained through optical coherence biometry (Biograph WaveLight OB820®).
Results:
YAG laser capsulotomy was performed 37.8±9.8 months after surgery in group 1 and 40.6±8.6 months in group 2 (p=0.125). Significant changes were found in the lens effective position after treatment in the 2 groups. The YAG posterior capsulotomy led to a change of anterior chamber depth in group 1 from 4.03±0.32 mm to 3.86±0.34 mm (p=0.02) and in group 2 from 4.03±0.37 mm to 4.14±0.45 mm (p=0.025). After YAG laser posterior capsulotomy, no significant changes were observed in mean spherical equivalent, sphere or cylinder for both groups (p>0.05).
Conclusion:
YAG laser posterior capsulotomy can induce a significant change in the IOL position according to the IOL type; however, the refractive change after treatment is clinically insignificant.
Related Concept Videos
Group Design
Study Designs in Epidemiology
Observational studies are those where the researcher does not intervene but rather observes natural variations. They include cross-sectional, cohort, and...
Study Design in Statistics
Does aspirin reduce the risk of heart attacks? Is one brand of fertilizer more effective at growing roses than another? Is fatigue as dangerous to a driver as the influence of alcohol? Questions like these are answered using randomized experiments with proper...
Factorial Design
Design Example: Identifying the Locations of Monuments in the Field Using Global Positioning System Device
Bioavailability Study Design: Single Versus Multiple Dose Studies


