A 28-year-old patient has long-distance vision double vision and double vision for many years, especially recently, when driving at high speed, four lanes are often seen as eight lanes, which has caused a lot of inconvenience to life, and he thought that the original glasses were not suitable, so he came to the hospital for treatment. After a detailed eye examination, we found that the patient had mild esotropia, because there was no obvious abnormality in appearance, and for this patient's condition, we added a prism to the patient's original myopia degree, and the patient's symptoms of double vision and double vision were significantly improved. The problem that has plagued him for many years has been solved with a special glasses, so is the prism so magical?
Prism is a kind of transparent lens with a triangular optical cross-section, which can change the direction of the beam and have the ability to refract light.
The principle of a prism
After the light passes through the prism, it is refracted to its base, and the image is displaced to its tip, according to the law of the displacement of the image and the magnitude of the squintism, the prism is placed in front of the strabismus eye, and the power of the triangular prism is constantly changed, until the external object is imaged in the macula of the strabismus eye, and the eyes have a common visual direction, and the diplopia can be eliminated.
What kind of patient is suitable for prisms
1.Strabismus at a small angle.
2.Residual squint power after strabismus.
3.Symptomatic heterophoria or rotational strabismus, vertical strabismus.
4.Essential nystagmus.
5.Auxiliary function insufficiency, auxiliary paralysis.
6.The young age is not suitable for surgery for the time being.
Receding eye syndrome, paralytic strabismus due to trauma
The principle of wearing a prism
Give the patient optometry and determine the patient's prism examination power, try on the prism on the basis of the patient's original diopter power, generally start the trial according to the patient's actual examination prism power of 1 3, and distribute the prism power evenly to both eyes, try on until the symptoms disappear or improve significantly, and then decide the prescription of glasses. The tip of the prism points in the direction of the eye deviation.
Double vision, diplopia, and eye deviation are not terrible, and it is important to find the right method!
Contributed by: Wang Huan, a member of the pediatric ophthalmology group of Chaoju Ophthalmology.
Medical science is for reference only and is not used as a basis for diagnosis!
Original design, courtesy of the manufacturer.