Measurement of crystalline lens tilt in high myopic eyes before cataract surgery using swept-source optical coherence tomography

Abstract

Background: To measure the crystalline lens tilt in eyes with various degrees of myopia before cataract surgery using swept-source optical coherence tomography (SS-OCT). Methods: We used SS-OCT (IOLMaster 700) to scan 131 emmetropic eyes (axial length < 24.5 mm), 25 mild/moderate myopic eyes (axial length 24.5-26 mm), and 123 high myopic eyes (52, 29, and 42 eyes with axial lengths of 26-28, 28-30, and > 30 mm, respectively) as part of the routine preoperative examination before cataract surgery. SS-OCT involved B-scans along six meridians. The data were analyzed to assess the magnitude and orientation of the lens tilt and their correlation with other optical biometric parameters. Result: The mean tilt was 3.36 ± 0.98°in emmetropic eyes, 3.07 ± 1.04°in mild/medium myopic eyes, and 2.35 ± 1.01°i n high myopic eyes. Tilt correlated significantly and inversely with axial length (Pearson's r = − 0.427, P < 0.001). The crystalline lens tilt predominantly faced the upper outer quadrant relative to the visual axis, symmetrically in both eyes, with mean angles of 24.32°and 147.36°in the right and left eyes, respectively. The variability in the lens tilt direction increased with increasing axial length (χ 2 test, P < 0.001). Conclusion:The magnitude of crystalline lens tilt decreased with increasing axial length. The direction of tilt was predominantly towards the upper outer quadrant in both eyes. The variability in the tilt orientation increased with increasing axial length. Trial registration: NIH (clinicaltrial.gov), NCT03062085. Registered 23 February 2017.

Distributions of crystalline lens tilt and decentration and associated factors in age-related cataract

“… 12 Other studies using IOLMaster 700 reported that the mean tilt of crystalline lens was 3.36 to 4.3 degrees toward the nasal direction in both eyes. 6 , 14 However, these methods have relatively poor image resolution and cannot quantitatively measure the tilt and decentration of lens because of technical problems. As a result, previous studies of lens biometric parameters produced inconsistent results.…”

Comparison of Vault Measurements Using a Swept-Source OCT-Based Optical Biometer and Anterior Segment OCT

“…This non-contact high-resolution biometric instrument utilizes a tunable laster centered at 1,055 nm to generate B scans that enable operators to quantify ocular data ( 16 ). The IOLMaster700 can perform 44 mm scans at 22μm resolution ( 12 ), and can detect crystalline lens features including decentration or tilt as the generated B-scans are shown as full-length OCT images of anatomical details along longitudinal sections through the full eye ( 17 ). At present, this instrument cannot directly measure postoperative lens vault values, and there have been no prior publications regarding the use of the IOLMaster700 for measurements made in the context of ICL implantation.…”

Visual Axis and Stiles–Crawford Effect Peak Show a Positional Correlation in Normal Eyes: A Cohort Study

“…A recent study showed that crystalline lenses were tilted outward, and the tilt magnitude tended to be lower in myopic eyes than in non-myopic eyes. 49 If the crystalline lenses are tilted inward in myopic eyes, the first nodal point is shifted nasally so that it may affect the visual axis position on the pupil plane. Further studies are required to test these hypotheses.…”