Reflex neuroses arising from ocular and nasal abnormalities : oration in ophthalmology / by S. Lewis Ziegler.

  • Ziegler, S. Lewis (Samuel Lewis), 1861-1926.
Date:
[1908]
Catalogue details

Licence: In copyright

Credit: Reflex neuroses arising from ocular and nasal abnormalities : oration in ophthalmology / by S. Lewis Ziegler. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

    9/26 (page 7)
    effort made to overcome errors in the static refrac- tion, or to correct axial defects. These errors are hypermetropia, myopia, and astigmatism in varying combinations. As the cihary muscle may act irreg- tilarly, spasmodically, and unequally, its action must be wholly suspended by complete cycloplegia in or- der that the ametropia may be accurately measured. Having carefully ascertained the total refractive error, v^e must make due allowance for the free play of the ciliary muscle in prescribing the correcting glass. Failure at this point may wholly annul our efforts to remove the exciting cause. Too strong a glass will blur the vision, while too weak a cor- rection will not relieve the strain; hence, failure from either extreme should be avoided by ordering the happy medium. 2. Unusual accommodative strain is a fruitful source of reflex disturbances. The accommodation should, therefore, be tested in every case, and a careful record made. Subnormal accommodation may be found in the eyes of children or youths, as well as in those of adults, but it is manifested chief- ly after the age of forty, when it is known as pres- byopia. The eye may be quite comfortable under the distance correction and still suffer whenever near work is attempted. An additional correction for near work must, therefore, be ordered in every case of subnormal accommodation, whether young or old. Neglect of this simple measure will often result in failure to secure the desired relief. 3. Heterophoria, or imbalance of the extraocular muscles, has long been conceded to be a most vicious agent in the causation of these reflex neu- roses. Errors in the vertical muscles (hyperphoria) are probably more active because harder to over- come, while the horizontal disturbances (esophoria and exophoria), although more amenable to treat-