|
Cyclotropia is a form of strabismus in which, compared to the correct positioning of the eyes, there is a torsion of one eye (or both) about the eye's visual axis. Consequently, the visual fields of the two eyes appear tilted relative to each other. The corresponding ''latent'' condition – a condition in which torsion occurs only in the absence of appropriate visual stimuli – is called cyclophoria. Cyclotropia is often associated with other disorders of strabism, can result in double vision, and can cause other symptoms, in particular head tilt. In some cases, subjective and objective cyclodeviation may result from surgery for oblique muscle disorders; if the visual system cannot compensate for it, cyclotropia and rotational double vision (cyclodiplopia) may result.〔See section "Discussion" in: PMCID: PMC2636065.〕 The role of cyclotropia in vision disorders is not always correctly identified. In several cases of double vision, once the underlying cyclotropia was identified, the condition was solved by surgical cyclotropia correction. Conversely, artificially causing cyclotropia in cats leads to reduced vision acuity, resulting in a defect similar to strabismic amblyopia. == Diagnosis == Cyclotropia can be detected using subjective tests such as the Maddox rod test, the Bagolini striated lens test, the phase difference haploscope of Aulhorn,〔 or the Lancaster red-green test (LRGT). Among these, the LRGT is the most complete. Cyclotropia can also be diagnosed using a combination of subjective and objective tests. Before surgery, both subjective and objective torsion should be assessed.〔Phyllis E. Weingarten and David L. Guyton, (Volume=6, Chapter 97: Surgery to Correct Cyclotropia )〕 Experiments have also been made on whether cyclic deviations can be assessed by purely photographic means. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cyclotropia」の詳細全文を読む スポンサード リンク
|