Fig 1.
Biometric measurements provided by 3-dimensional optical coherence tomography (3-D OCT).
The 3-D OCT images show the scanned capsule, which is an imaginary line of the crystalline lens visualized from the anterior and posterior capsule, provided by the built-in algorithm of the laser system. The equator plane is a straight line that connects both ends of the imaginary lines. Anterior chamber depth (ACD) is determined by calculating the distance along the visual axis between the corneal epithelium and anterior lens surface by OCT. The lens meridian parameter (LMP) is the vertical distance from the corneal apex to the equator plane of the crystalline lens. The anterior segment length (ASL) was calculated by adding the lens thickness (LT) to the ACD. The crystalline lens was also analyzed by dividing it into an anterior part (aLT) and posterior part (pLT), bordered by the equator plane.
Table 1.
Parameters for femtosecond laser-assisted pretreatment.
Table 2.
The combinations of biometric measurement for effective lens position (ELP) prediction and intraocular lens power calculation.
Table 3.
Clinical characteristics of patients with femtosencond laser-assisted cataract surgery in training set (n = 92).
Table 4.
Regression formulas for effective lens position (ELP) prediction and ELP prediction error from each combination from training set (n = 92).
Table 5.
Predictive accuracy derived from each combination in a training set (n = 92).
Fig 2.
Correlation of preoperative lens thickness with prediction error derived from each intraocular lens formula in training set (n = 92).
AL and ACD by PCI (A), AL and ACD by AS 3-D OCT (B), AL and LMP (C), AL, ACD, and aLT (D), AL, ACD, and LT (E), AL, LMP, and pLT (F), AL and ASL (G), AL, ACD, aLT, and pLT (H). AL = axial length; ACD = anterior chamber depth; PCI = partial coherence interferometry; AS 3-D OCT = anterior segment 3-dimensional optical coherence tomography; LMP = lens meridian parameter; aLT = anterior part of lens thickness; LT = lens thickness; pLT = posterior part of lens thickness; ASL = anterior segment length.
Table 6.
Clinical characteristics of patients with femtosencond laser-assisted cataract surgery in the test set (n = 53).
Table 7.
Predictive accuracy derived from new intraocular lens (IOL) calculation formula compared with the accuracy of the Barrett-Universal II, Haigis, Hill-RBF, Hoffer Q, SRK/T, and T2 formulas in test set (n = 53).