ASTHENOPIA.
When the patient complains of inability to continue the use of the eyes for near work as reading and sewing owing to blurring of the objects, browache, &c., the cause may be simply due to follicular conjunctivitis, which may be recognised by everting the lower lid, when the rows of swollen lymph follicles will come into view on the lower fornix of the con junctiva. An ointment of io grs. Sulphate of Copper to r oz. Vaseline will usually give speedy relief, or a r gr. per oz. solution of Zinc Sulphate may be used.
In accommodative asthenopia the affection is usually due to hyper metropia, the overworked ciliary muscle being unable to meet the demands made upon it, and the obvious remedy will consist in the use of suitable convex glasses. Myopia and astigmatism will likewise demand suitable correction in other cases.
Attention must in all cases he given to the general health of the patient, and he must only be permitted to work in a proper light and in a proper attitude, and all overwork of the eyes should he strictly guarded against.
The treatment of asthenopia caused by insufficiency or weakness of the external ocular muscles will consist in the correction of any errors of refraction which may be present, after which the defective power of the muscles can be overcome by suitable prisms and systematic exercise of the weakened muscles. Pilocarpine or Eserine solutions may be occa
sionally instilled with the view of stimulating the ciliary muscle. In the obstinate muscular asthenopia met with in neurasthenic subjects, the treatment of the underlying neurotic condition will require close attention. The writer has found unmistakable benefit to follow the instillation of a to 2 per cent. solution of Sodium Formate two or three times a day.
When the asthenopia is retinal, or depending upon some exhaustion of the general nervous system, as may be seen after recovery from serious illness, the eyes should as far as possible be rested from all close work, and, if there be any photophobia, light should be modified by the use of smoked glasses. Every means of restoring the general health should be attended to, and the treatment recommended for amblyopia be used i.e., hypodermic injection of Strychnine, with Iron and Quinine internally at the same time, or large doses of Easton's Syrup may be prescribed. The spasms of accommodation may be relieved by Cocaine or Atropine occasionally dropped into the eye.