Modified vertical rectus belly transposition plus medial rectus recession promising option for chronic sixth nerve palsy

Modified vertical rectus belly transposition with ipsilateral medial rectus recession (mVRBT-MRc) showed better results in correcting esotropia than augmented superior rectus transposition with ipsilateral medial rectus recession (aSRT-MRc) in patients with chronic sixth nerve palsy as per a study that was published in the journal JAMA Ophthalmology. 

Vertical rectus belly transposition (VRBT) and superior rectus transposition (SRT) can be performed simultaneously with ipsilateral medial rectus recession (MRc) and both these procedures are effective for chronic sixth nerve palsy. But there is not much literature on which procedure is superior. Hence researchers conducted a study to compare the effectiveness of modified VRBT plus MRc (mVRBT-MRc) vs augmented SRT plus MRc (aSRT-MRc) on patients with chronic sixth nerve palsy. The study was carried out from January 15, 2018, to May 24, 2021. 

A parallel-design, double-masked, single-center, randomized clinical trial was conducted. Eligible Chinese participants with unilateral chronic sixth nerve palsy were randomly assigned to receive either mVRBT-MRc (VRBT group) or aSRT-MRc (SRT group). The follow-up visits were scheduled at 1 month and 6 months. Change of horizontal deviation in primary position from baseline to 6 months was the primary outcome of the measurement. 

Results:

• 25 eligible participants with a mean (SD) age of 45.4 (12.6) years participated in the study.
• Of the total 10 were male participants and 15 were female participants.
• Thirteen participants were randomly assigned to the VRBT group, and 12 were randomly assigned to the SRT group.
• At baseline, the mean horizontal deviation was 65.7 prism diopters (Δ) in the VRBT group and 60.5Δ in the SRT group.
• Similar amounts of MRc were performed in both groups. At 6 months, the horizontal deviation changed by 66.3Δ in the VRBT group and by 51.5Δ in the SRT group from baseline.
• The adjusted group difference was 10.9Δ, favoring the VRBT group.
• Four times as many participants corrected more than 60Δ with mVRBT-MRc compared with aSRT-MRc.
• The group difference in the improvement of abduction limitation was −0.2.
• Although there was a higher proportion of under correction in the SRT group, no differences were identified for other suboptimal outcomes between groups. 

Thus, the researchers concluded that mVRBT-MRc showed a better effect in correcting esotropia than aSRT-MRc and they also suggested that mVRBT-MRc may be a promising alternative surgical procedure for chronic sixth nerve palsy, particularly for large esotropia of more than 60Δ. 

To read the full article, click here: 10.1001/jamaophthalmol.2022.2856 

Yao J, Jiang C, Wang X, et al. Effect of Modified Vertical Rectus Belly Transposition vs Augmented Superior Rectus Transposition Plus Medial Rectus Recession for Chronic Sixth Nerve Palsy: A Randomized Clinical Trial. JAMA Ophthalmol. 2022;140(9):872-879.