Abstract
Purpose :
Nasal and temporal partial tenotomies of the vertical rectus muscles differentially correct vertical deviation (VD) in adduction, VD in abduction, V- or A-Pattern and ex- or incyclotropia. In an initial analysis of a large case series we defined clinical indications for this operation and differences in effect.
Methods :
A retrospective analysis was carried out of patients who were treated between 1996 and 2021 in our clinic. All patients were included who had a nasal or temporal partial tenotomy of the vertical rectus muscles. Patients were excluded if postoperative measurements were missing. The changes in angle of strabismus in VD in adduction, in gaze ahead, VD in abduction, V- or A-pattern and ex- or incyclotropia were calculated by subtracting the measurement three months postoperatively from the pre-operative measurement. The Mann-Whitney U test was used in SPSS (version 27) to detect significant differences between effects.
Results :
In total 126 patients were included, 100 of whom were treated by nasal and 26 by temporal partial tenotomy. Twenty-six patients were excluded due to missing postoperative measurements. The median age at operation was 48 years, range 8 - 70 years. Seventeen patients treated by nasal and seven patients by temporal partial tenotomy did not have sufficient binocular vision for a cyclotropia measurement. Sixteen patients had first strabismus surgery, 58 had re-operations, six had traumatic strabismus, 10 had an eye muscle palsy, 17 had vertical nystagmus, and 19 had unicoronal craniosynostosis. The change in angle of strabismus is depicted in the Figure. Effect of surgery was analyzed for inferior and superior rectus together and absolute values were used for change in angle. There was a statistically significant difference between nasal and temporal partial tenotomy for VD in adduction (Z= 4.215, p<0.001) and for VD in abduction (Z=-2.365, p=0.018) but not for pattern and cyclotropia.
Conclusions :
The significant differences between the change of VD in adduction as compared to that in abduction, show that nasal and temporal partial tenotomies are suited for an isolated small VD in either ad- or abduction. It remains unclear why the change of cyclotropia by temporal partial tenotomies (N=19) was so small.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.