Quantitative Analysis of Human Corneal Lenticule Surface Microstructure Irregularity with 3D Optical Profiler Using White Light Interferometry

ABSTRACT

Purpose

To quantitatively evaluate the cutting quality of small incision lenticule extraction (SMILE) by measuring human corneal lenticule surface roughness in different areas with white light interferometer.

Method

A white light interferometer was used to quantitatively measure the corneal lenticule surface roughness in different areas. Sixty-three myopic patients (102 eyes) who underwent SMILE surgery were recruited. The surface roughness of the central, pericentral, and peripheral parts of the corneal lenticule surface was measured in both the anterior and posterior planes. Differences in corneal lenticule surface roughness were analyzed between different myopic groups.

Results

The surface roughness of the anterior plane of the corneal lenticule was lower than the posterior plane in various areas (central, pericentral, and peripheral parts) (P < .01). Surface roughness gradually increased from the center to the periphery, in both the anterior and posterior planes (P < .01). There were no significant differences in the surface roughness of the central part in both the anterior and posterior planes between the low and high myopic groups. The surface roughness of the high myopic group was higher than that of the low myopic group in the peripheral part (P < .01). There were no significant differences among the three cylinder-specific groups. There was no significant correlation between two paired eyes. A positive correlation between posterior central surface roughness and the percentage tissue altered score (PTA) was found (r = 0.248, P = .012).

Conclusions

The cutting surface of the corneal lenticule performed by femtosecond laser was evaluated with a white light interferometer and displayed inhomogeneity. Deeper cutting with higher myopia and some intraoperative complications, such as suction loss, may result in larger irregularities.

KEYWORDS:

• Surface roughness
• lenticule
• white light interferometry
• cornea
• refractive surgery

Acknowledgments

This study has been supported by the National Natural Science Foundation of China (No.81873684, 81670884) and Science and Technology Foundation of Tianjin Eye Hospital (No. YKQN1919). The authors alone are responsible for the content and writing of the paper.

Disclosure statement

No conflicting relationship exists for any author.

Additional information

Funding

This study was supported by the National Natural Science Foundation of China (81873684, 81670884) and Science and Technology Foundation of Tianjin Eye Hospital (No. YKQN1919). The funding organization had no role in the design or conduct of this research.