Effects of postural changes in eye cyclotorsion and pupil centroid shifts on corneal refractive surgery / 中华实验眼科杂志

The main purpose of corneal refractive surgery is not only to improve vision, but also to improve visual quality, which is a higher level of visual ability except vision.At present, most corneal refractive surgeries take the pupil center as the center of examination and treatment, since changes in body position may result in pupil centroid shifts and eye cyclotorsion and postoperative visual quality can be affected by undercorrected astigmatism, induced astigmatism and increased high order aberration that results from eccentric cutting occurring during corneal refractive surgery.The measurement of centroid shifts and eyeball rotation that can be attributed to the change of body position guiding the design of surgery is of great significance to enhance the accuracy of pupil center positioning, improve the safety of surgery and promote the postoperative visual quality.In this article, the relevant literature on the measurement methods of the pupil centroid shifts and ocular cyclotorsion, pupil centroid shifts and ocular cyclotorsion measured by iris recognition technology in response to changes in body position, and the effects of posture-related pupil centroid shifts and ocular cyclotorsion during refractive surgery on postoperative visual quality (postoperative astigmatism, aberration, and modulation transfer function) were reviewed.

Influencing factors for eye cyclotorsion and pupil centroid shift during LASIK / 眼科

Objective To investigate the influencing factors for eye cyclotorsion and pupil centroid shift during LASIK.Design Non-controlled retrospective case series.Participant 131 patients (262 eyes) with myopia received bilateral LASIK.Methods Eye cy- clotorsion and pupil centroid shift were measured with Custom Vue~(TM) software during operation and compared with age,gender,right or left eye,flap-making method,spherical equivalent (SE),pupil diameter before and during operation.Main Outcome Measures The de- gree of eye cyclotorsion and distance of pupil centroid shift during LASIK.Results The mean eye cyclotorsion during LASIK was 3.07??2.07?(0?-8.6?).The mean pupil centroid shift was 0.33?0.14 mm (0.04-0.51 mm).The eye cyclotorsion was relevant to preoperative pupil size,difference of pupil size before and during operation,and preoperative SE (r=0.188,0.156,0.130,all P7.0 mm was higher than that of with pupil diameter≤7.0mm (3.35??2.17?,2.71??1.89?,P=-0.014).Pupil centroid shift was higher in fight eyes than that in left eyes (0.39?0.12 mm,0.28?0.13 mm,P=0.000).Conclu- sion Eye cyclotorsion and pupil centroid shift during LASIK can be measured with Custom Vue~(TM) system.The eye cyclotorsion may be influenced by the preoperative pupil size.The pupil centroid during LASIK was more significant in the right eyes than in the left eyes.