Indication for Refraction Intervention in Adult Patients with Strabismus and theResults of Subsequent Therapeutic Procedure

Overview

The authors estimated the contribution of the refraction intervention and a possibleevolution in the position of eyes in 102 adult individuals consideringa refraction intervention. The indications for this intervention were a disorder in eye position or amblyopia in those who were interested in this operation and wereexamined in the years 1996 to 2002. The basic refraction examination was alwayssupplemented by a detailed orthoptic analysis. Based on this examination theintervention was not recommended in 14 examined subjects (14%). ARK representedthe contraindication of the refraction intervention in 9 patients, sincesubsequent changes in the size of the deviation or operation adjustment ofstrabismus could result in diplopia. An excessive convergence with a high AC/Ain hyperopia was also considered as an unsuitable indication, since a lastingcosmeticandfunctional significantconvergentdeviationintoneardistances couldnot be excluded. Five patients declined from the refraction intervention on thebasis of this explanation.The paper is mainly dealing with an analysis of the development of position of theeyes and binocular functions in 46 adult patients, who decided to undergo a refractionintervention and further orthoptic care after a complex stroboscopic andrefractionexamination.Theadjustment of refractive errorwasmade by theLASIKmethods (Laser in Situ Keratomileusis) on 69 eyes (80 %) and CLE (Cleans LensExtraction) on 17 eyes (20 %). The orthoptic analyses before and the refractionintervention revealed that in all 29 even only partially accommodating esotropia,the deviation was diminished after the refraction intervention on the average by+11.2 degrees (in the rage of +2 degrees to +30 degrees) to 5.4 degrees (in the rangeof parallel position to +20 degrees) in the predominantly represented hyperopia,but also in 6 myopias. The improved position of the bulbs was not directlyassociated with the degree of hyperopia with the original deviation.The deviationafter the refractioninterventionin23 patients (79%) with esotropiawasnot higherthan +5 degrees. The cosmetic position of the eyes was completely satisfactoryand did not therefore represent even indication for the operation. The 9 patients(35%) with esotropia and hyperopia there ware an improvement of binocularfunctions. It could be theoretically due to the newly developed emetropia makingpermanent optimal sensory information possible. In all 17 exotropias there werenot any significant changes in the size of deviation and the binocular functionswere not reestablished, if they were not retained before. The position of eyes wassolved surgically in 12 patients, while exotropia predominated in two thirds ofthem. The weakening or strengthening interventions on horizontal straight muscleswere selected according to character of strabismus in 11 patients. Recessionof the lower oblique muscle was indicated one case only for the simultaneouslypresent torticollis with exotropia. The residual deviation was not greater than 5degreesimmediately after theoperation or duringthe followingmonths.Binocularfunctions were not reestablished in any patients. A alternate suppression orsuppression of perception on one eye were proved.

Key words:
binocular vision, CLE, LASIK, strabismus, refractive errors