Accuracy of Intraocular Lens Calculation by SRK/T Formula in Pediatric Cataracts
Thanapaisal, S.; Wongwai, P.; Phanphruk, W.; Suwannaraj, S.
Journal of the Medical Association of Thailand 98(Suppl 7): S198-S203
2015
ISSN/ISBN: 0125-2208 PMID: 26742391 Document Number: 16176
To examine the accuracy of the intraocular lens calculation by SRK/T formula in pediatric cataract patients, by means of the prediction error after the cataract surgery. A retrospective review of pediatric patients requiring cataract extraction with intraocular lens implantation, between January 2006 and December 2013 was performed. Post-operative spherical equivalent was compared with the predicted calculation value from pre-operative SRK/T measurement, defined as prediction error (PE). 139 eyes from 106 patients were studied. The median age of patients at surgery was 4.56 years (IQR, 14). The two most common causes of cataract were idiopathic and traumatic; 85 eyes (61.2%) and 36 eyes (25.9%), respectively. Primary intraocular lens (IOL) implantation was performed in 87 (62.6%) eyes. The mean PE was -1.32±1.89 D (-7.78, 2.24). At one to three months after surgery, the mean PE of IOL in bag and sulcus were -0.87 D and -2.02 D, respectively. In non-traumatic group, the mean PE of IOL in bag and sulcus were -1.1 D and 2.28 D, respectively, whilst the traumatic group was -0.33 D and -1.16 D, respectively. Post-operative PE within ±1 diopter was found in 30 eyes (37.97%) at one to three months of follow-ups. The majority of post-operative refraction was more myopic than the taigeted refractive error, which was calculated by SRK/T formula. Aiming for a more hyperopic target and IOL implantation in the bag would decrease the post-operative prediction error in the use of the SRK/T formnula in pediatric cataract patients.