Search results
Results from the WOW.Com Content Network
Light from a single point of a distant object and light from a single point of a near object being brought to a focus. The accommodation reflex (or accommodation-convergence reflex) is a reflex action of the eye, in response to focusing on a near object, then looking at a distant object (and vice versa), comprising coordinated changes in vergence, lens shape (accommodation) and pupil size.
This test detects the afferent pupil defect, also referred to as the Marcus Gunn pupil. It is conducted in a semidarkened room. In a normal reaction to the swinging-flashlight test, both pupils constrict when one is exposed to light. As the light is being moved from one eye to another, both eyes begin to dilate, but constrict again when light ...
There are many types of accommodation anomalies. It can be broadly classified into two, decreased accommodation and increased accommodation. [50] Decreased accommodation may occur due to physiological (presbyopia), pharmacological (cycloplegia) or pathological. [50] Excessive accommodation and spasm of accommodation are types of increased ...
However, errors in this relationship can cause problems, such as hyperopic individuals having a tendency for crossed eyes because of the over exertion of their accommodation system. Clinically, accommodative convergence is measured as a ratio of convergence, measured in prism diopters, to accommodation, measured in diopters of near demand.
The Van Herick technique is an eye examination method used to determine the size of the anterior chamber angle of the eye.. Glaucoma is currently the principal cause of irreversible blindness in the world. [1]
For an adequate test, vision must not be entirely lost. In dim room light, the examiner notes the size of the pupils. The patient is asked to gaze into the distance, and the examiner swings the beam of a penlight back and forth from one pupil to the other, and observes the size of pupils and reaction in the eye that is lit.
In this condition, amplitude of accommodation of a person is lesser compared to physiological limits for his age. [1] AI is generally considered separate from presbyopia, but mechanically both conditions represent a difficulty engaging the near vision system (accommodation) to see near objects clearly. Presbyopia is physiological insufficiency ...
Positive relative accommodation (PRA) in biology, is a measure of the maximum ability to stimulate eye accommodation while maintaining clear, single binocular vision. [1] This measurement is typically obtained by an orthoptist , ophthalmologist or optometrist during an eye examination using a phoropter .