Peripheral refraction measuring method based on OCT technology

Abstract

The invention relates to a peripheral refraction measuring method based on OCT (optical coherence tomography) technology. The peripheral refraction measuring method based on OCT technology comprises the following steps: an OCT system is used for one-time imaging to refraction medium and retina inside an bulbus oculi so as to obtain OCT image; image processing software is used for analyzing OCT image so as to obtain forms and range information of all refraction interfaces and retina; an optical path tracing method is used for obtaining center refractive power in the visual axis direction and peripheral refraction force forming any angle with a visual axis; and the difference value of the peripheral refraction force at any angle and the center refraction force is calculated so as to obtain the peripheral refraction force value. According to the method, all that is needed is to acquire full-eye OCT image in one step through a full-eye imaging high resolution OCT system, ongoing implementation can be processed through software, and the method is quick and accurate in measuring.

Description

technical field [0001] The invention relates to the fields of medicine and optoelectronics, in particular to a method for measuring peripheral refraction based on OCT technology. Background technique [0002] The concept of peripheral refraction was first proposed by Ferree et al. in 1931. Peripheral refractive power refers to the refractive power in the peripheral field of vision at a certain angle with the visual axis, that is, the focusing state of light rays at a certain angle with the visual axis after entering the eyeball. According to the focus of the incident light and the relative position of the retina, it can also be divided into relative myopia and relative hyperopia. The central and peripheral refractive power are the most important indicators to completely evaluate the refractive state of the human eye. The farther you go to the periphery, the greater the difference between the value of the peripheral refractive power and the central refractive power, and high...

AI Technical Summary

Problems solved by technology

These methods have obvious defects: (1) When the eye position is turned, the shape of the eyeball at the posterior pole will be affected due to the contraction of the extraocular muscles; (2) According to the current measurement method, the subject’s head is fixed on the instrument bracket, The lower part is placed on the jaw rest, the forehead is close to the forehead rest, and the gaze target is fixed in front of the instrument. However, due to individual differences in the positions of the forehead and eyeballs relative to the forehead, there is a certain error in the measurement angle of peripheral refraction.

(3) The measurement time is long. According to the current practice, it takes at least 40 minutes to measure the peripheral refractive power of 7 angles, and it takes 1.5 hours if the time for dilation of the pupils is included; The reduction directly affects the measurement results

(4) Due to the reason of (2), the optotype can only be set at some fixed angles, therefore, the peripheral refraction at any angle cannot be measured

(5) The fixation target is generally set in front of the eyes, which will cause the subject's near perception adjustment and affect the results

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