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Augmented superior rectus transposition procedure in Duane retraction syndrome compared with sixth nerve palsy
Mohammadreza Akbari1, Setareh Shomali1, Arash Mirmohammadsadeghi1
1Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, South Kargar, Qazvin SQ, Tehran, 13352, Iran.
Purpose:
Superior rectus transposition (SRT) with medial rectus recession has been used for the treatment of sixth nerve palsy and esotropic Duane retraction syndrome (DRS). The purpose of this study was to compare the results of augmented SRT (with scleral fixation) without medial rectus recession in DRS and sixth nerve palsy.
Methods:
Patients with unilateral esotropic DRS (DRS group) and sixth nerve palsy were included in this prospective, comparative study and underwent SRT. Preoperative forced duction testing was negative or slightly positive in both groups. Prospective measurements were compared between the two groups.
Results:
There were 11 patients in the DRS group and 11 patients in the sixth nerve palsy group. The mean preoperative esotropia decreased from 20.9 ± 6.0 prism diopter (PD) at far to 13.2 ± 5.8 PD in the DRS group (P = 0.003). The same measurement improved from 28.0 ± 8.5 PD to 8.4 ± 7.3 PD in the sixth nerve palsy group (P = 0.003). In the sixth nerve palsy group, the improvement in primary gaze esotropia and abnormal head posture was more than the DRS group (Both P < 0.001).The average dose effect for SRT was 7.8 ± 2.2 PD in the DRS group and 19.2 ± 4.6 PD in the sixth nerve palsy group. Although objective intorsion was significantly induced after SRT, subjective torsion was not significant after surgery in both groups.
Conclusion:
SRT appears to be more effective in improving primary gaze deviation and head posture in sixth nerve palsy compared with DRS. Subjective torsional and vertical diplopia were rare in both groups.
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