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Effect of bilateral superior oblique split lengthening on torsion
Jitendra Jethani1, Kuntal Shah, Sonal Amin
1Department of Pediatric Ophthalmology and Strabismus, Dr. Thakorbhai V Patel Eye Hospital, Vadodara, Gujarat, India.
Introduction:
Superior oblique split lengthening (SOSL) is done for weakening of superior oblique. It corrects the superior oblique overaction (SOOA) and A pattern. Its effect on the torsion of the eye is not known. We present our data on the effect of this particular procedure on torsion.
Materials And Methods:
We did a study of 16 patients (32 eyes) who underwent bilateral SOSL and compared the disc foveal angle (DFA) preoperatively and postoperatively. The split lengthening was done from 4 mm to 7 mm depending upon the overaction of superior oblique.
Results:
The mean age was 15.3 ± 8.4 years. Mean preoperative DFA in the right eye (RE) was -3.9° and in the left eye (LE) was -2.9°. Mean postoperative DFA in RE was 0.2° and in LE was 0.9°. The mean change in the DFA for RE was 4.1° ± 1.3° and for LE was 3.8° ± 1.2°. All the patients were aligned horizontally within 6 prism diopter and no pattern and no diplopia postoperatively. The A pattern was corrected in all the patient postsurgery. For each mm of surgery, an improvement of 0.8° was seen in the DFA.
Conclusion:
We report the effect of SOSL on torsion. The SOSL reduces intorsion postsurgery and is, therefore, a valuable procedure in SOOA where both pattern and in torsion needs to be corrected.
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