Interchangeability of anterior chamber depth and pachymetry measurements: IOLMaster 700 vs Orbscan II
Session Details
Session Title: Presented Poster Session: Keratorefractive Results II
Venue: Poster Village: Pod 2
First Author: : F.Sousa Neves PORTUGAL
Co Author(s): : C. Santos M. Paulo A. Ramos J. Sequeira
Abstract Details
Purpose:
To compare the agreement between anterior chamber depth (ACD) and central pachymetry (PAC) obtained with the new optical biometry device IOLMaster 700 (Carl Zeiss, Meditec, Jena, Germany) and those provided by the Orbscan II (Bausch & Lomb Surgical Inc., San Dimas, California, USA) for preoperative phakic IOL assessment.
Setting:
Department of Ophthalmology of Centro Hospitalar Vila Nova de Gaia/Espinho.
Methods:
In this cross-sectional study, we included 100 consecutive eyes of 50 myopic patients attending Refractive Surgery consultation between March and September of 2016. Measurements of ACD (corneal epithelium to lens) and PAC were compared using paired t-test and Bland-Altman analysis. Patients were also divided into three groups according to their spherical equivalent: Group I from -0.25 to -5.00 dioptres; Group II from -5.25 to -10.00 dioptres; Group III from -10.25 to -15.00 dioptres.
Results:
Mean age was 31.9±7,81 years. The ACD between the three groups, with IOLMaster and Orbscan was not statistically different. However, group III showed a significantly thinner PAC than group I (p<0,03). In more than 95% of all eyes, ACD and PAC measurements were higher with IOLMaster. The limits of agreement between the two methods were -0.10 to 0.01 millimetres (ACD) and -26.0 to 13.4 microns (PAC), estimated by a Bland-Altman plot with 95% confidence interval.
Conclusions:
IOLMaster 700 underestimates both ACD and PAC in myopic eyes. Anterior chamber depth is crucial in pre-operative assessment of anterior chamber IOL implantation. Therefore, attention should be devoted to IOLMaster ACD values within a suspicious range
Financial Disclosure:
NONE