Asthenopic symptoms can have several causes:
- Excessive strain on the healthy eye, for example, due to long close-range work at too short a working distance, activity at a computer workstation with unsuitable glasses
- Prolonged work under unfavorable lighting conditions such as inadequate lighting, incorrectly mounted light fixtures, twilight, poor light and shadow contrast, too intense light exposure, glare or irritating reflections
Uncorrected or inadequately corrected refractive errors of the eye and muscular asthenopia.
- Uncorrected or inadequately corrected refractive errors or faulty corrections can lead to spasm of the internal eye muscles. The discomfort is to be corrected by an optimal compensation of the defective vision.
- Disturbed eye muscle balance (heterophoria) can cause double vision. To avoid double vision, individual external eye muscles are overused. Typical for “muscular asthenopia”: The symptoms disappear if one eye is temporarily switched off, e.g. by covering it with frosted glass. In muscular asthenopia, correction with prismatic lenses can be helpful in some cases. Since this is an intervention in the eye muscle balance, that is, a therapeutic procedure that may well have serious side effects if used improperly, the provision of a patient with prism lenses is reserved exclusively for the ophthalmologist.
Nervous asthenopia
If none of the external causes caused by refractive errors or disturbed eye muscle balance can be found as an explanation for asthenopic complaints, it is usually a purely functional problem, triggered by nervous exhaustion or psychological stress. Only an ophthalmologic diagnosis, which excludes organic causes, can provide information about this as well. To investigate the complaints, an examination in cycloplegia can be useful. For this purpose, the ciliary muscle is temporarily relaxed with medication. This dilatation of the pupil leads to a temporary disturbance of reading ability and driving ability.
More data on headache and the eye
According to a survey of German ophthalmologists, an average of 12.9 patients per week visit an ophthalmologist exclusively or primarily for headaches – extrapolated to all ophthalmologists in Germany, that’s 2.5 million headache patients per year. According to a survey in France, of the patients with daily headaches who go
- 19 percent to the ophthalmologist
- 13 percent to the neurologist,
- 11 percent to the gynecologist,
- 9 percent to the ENT doctor.
