Abstract
Abstract: :
Purpose: In strabismus surgery reoperations are frequently necessary since the effect of surgery is influenced by uncertainties (error sources). Sensitivity analysis was performed to determine the most influential uncertainties in strabismus surgery. Methods: Uncertainties were categorized as orthoptic and surgical measurement errors, anatomical and physiological variation and influence of binocular vision. For patients with infantile esotropia (ESO), accommodative esotropia (AE), esotropia with convergence excess (ECE) and exotropia (EXO). The contribution of each uncertainty was estimated by derivation of sensitivity and its measured or estimated variance. Contribution to variance of the effect was estimated for all uncertainties considered. Influence of anatomical and physiological factors was estimated using an analytical mechanical model of strabismus surgery, comprising muscle stiffness, stiffness in passive rotation and eye radius. Results: Conclusions: For all 4 categories of patients, orthoptic and surgical measurement errors and spring stiffness of the eye in passive rotation were most influential. There is a need for devices to measure the uncertain parameters more accurately, in order improve the outcomes of surgery.
Keywords: strabismus • strabismus: treatment