28. Comparison of Accuracy between Ultrasound B Scan and Partial Coherence Interferometry (IOL Master) in IOL (Intraocular Lens) Power Calculation
Muhammad Jahan Zaib Khan, Mohammad Asad Faraz, Abdul Ghafoor
ABSTRACT
Objective: To compare the accuracy between partial coherence interferometry and ultrasound B scan in intraocular power calculation.
Study Design: Non-randomized control trail study.
Place and Duration of Study: This study was conducted at the Department of Ophthalmology, Bahwal Vctoria and Civil Hospital, Bahawalpur, from June 2018 to January 2019.
Materials and Methods: IOL power and probable refractive outcome was calculated for each patient by both methods i.e. A-scan ultrasound biometry and IOL master (partial coherence interferometry). IOL power as calculated by IOL master was implanted in-the-bag by the author himself in specified time duration. Preoperative assessment was conducted for each patient, which included, best corrected visual acuity and subjective refraction, slit lamp examination for pupil examination, corneal clarity and cataract type, detailed fundus examination and intraocular pressure measurement. Post operative best corrected visual acuity and uncorrected and slit lamp examinations were performed at 1st day and 1st postoperative month. Mean and standard deviation was calculated for qualitative variables while frequency and percentage was calculated for quantitative variables. Mann-Whitney test was applied and P value less than or equal to 0.05 was considered as statistically significant.
Results: Total of 50 eyes were examined. Ultrasound A scan as well as partial coherence interferometry was performed for all the eyes and IOL power was implanted in accordance with IOL master. Mean absolute error was 0.686±0.493 with A scan while 0.731±0.528 according to IOL master (p=0.656). Mean numerical error was -0.531±0.498 with A scan while -0.612±0.590 with IOL master (p=0.460). Mean axial length was 24.48±3.37 and 24.92±3.54 with ultrasound A scan and IOL master, respectively (p=0.527).
Conclusion: It can be concluded by the results of this study that difference between the two modalities is not statistically significant in terms of refractive outcome.
Key Words: Ultrasound B scan, Partial Coherence Interferometry, Intraocular lens, Power, Axial length, Cataract surgery
Citation of articles: Khan MJH, Faraz MA, Ghafoor A.. Comparison of Accuracy between Ultrasound B Scan and Partial Coherence Interferometry (IOL Master) in IOL (Intraocular Lens) Power Calculation. Med Forum 2019;30(2):108-111.