Transactions 29th European Strabismological Association Meeting – de Faber (ed) © 2005 European Strabismological Association, ISBN 04 1537 211 9

Surgical treatment of upshoot and downshoots in Duane’s retraction syndrome

Ç. Karaca & A.S¸. S¸anaç

Hacettepe University Hospital Department of Ophthalmology, Ankara, Turkey

B. Sönmez

Military Hospital, Malatya, Turkey

ABSTRACT:

Purpose: The purpose of this study is to present our results in treating the upshoot or downshoot of Duane’s retraction syndrome in particular with splitting of the lateral rectus into a Y configuration at its insertion.

Methods: Six patients (4 male, 2 female) from our practice at Hacettepe University Hospitals, Ankara were included in this study. Subjects ranged in age from 3 to 21 at the time of surgery and follow up was from ten months to seven years. Three patients showed the motility characteristics of type 2 Duanes retraction syndrome, two patients type 3 and one patient had abduction deficit of the right eye and both abduction and adduction deficit of the left eye. All patients demonstrated a variable face turn and an upshoot was present in all patients. They underwent motility surgery to eliminate the overshoot and the face turn.

Results: The right eye was affected in two patients, left eye in two and the other two patients had bilateral involvement. All of them had deviation in the primary position (range: 12–60 pd, mean: 33.67 pd). The method of surgery to treat the upshoot was splitting of the lateral rectus muscle into a Y configuration in five patients and lateral rectus recession only in one patient. To relieve the deviation in primary position, lateral rectus recessions were performed in all patients. The splitting of the ends of the lateral rectus into a Y configuration resulted in improvement of the upshoot in all patients without any complications. Lateral rectus recession only had no effect on the upshoot. Conclusion: The splitting of the ends of the lateral rectus into a Y configuration is an easily performed operation which effectively improves the upshoot in patients with Duanes’ retraction syndrome. Performing simultaneous recession to the lateral rectus muscle combined with the splitting into Y configuration improves the outcome, especially in patients with marked globe retraction.

1 INTRODUCTION

Duane’s retraction syndrome is a congenital restrictive strabismus disorder that is characterised by a wide spectrum of extraocular muscle motility dysfunction. Heuck was the first to describe retraction of the globe in a patient with severe limitation of ocular motility. Alexander Duane published a 54 cases series in 1905 and described the retraction syndrome in following features: 1) congenital onset (acquired forms are rare), 2) severe limitation of abduction, 3) slight limitation of adduction, 4) globe retraction and narrowing of palpebral fissure on adduction, 5) Commonly associated elevation or depression on adduction.

Of special interest is the frequently associated upshoot and downshoot of the adducted eye which at times causes a cosmetic problem of almost grosteque proportions; namely when the cornea of the adducted eye disappears from view. At first glance such patients appear to have increased overaction of the inferior or superior oblique muscles. However surgical weakening

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procedures on these muscles is entirely ineffectual. Scott pointed out that the high muscle tension caused by the cocontraction of the horizontal rectus muscles or by structural thightness of the lateral rectus muscle when the lateral rectus muscle contracts results in a vertical effect by allowing the muscles slide over the globe when contracting (bridle effect). However it has been shown by CT and MRI scanning that it is actually not the muscles that slide over the surface of the globe but the globe that slips under the muscles. Because the vertical displacement of the horizontal muscles

during elevation and depression in relation to the orbital wall is negligible in most but not all

cases of Duane syndrome. It is because the horizontal rectus muscles maintain their vertical position with reference to the orbital walls that elevation or depression of the eyes will move the center of rotation above or below the muscle planes. This explains the bridle effect that occurs during co-contraction of these muscles when the eye is slightly elevated or depressed. Therefore the splitting of the lateral rectus muscle into a Y configuration that increases the width of insertion may decrease this briddle effect. The purpose of our study is to present our results in treating the upshoot or downshoot of Duane retraction syndrome in particular with splitting of the lateral rectus into a Y configuration at its insertion.

2 PATIENTS AND METHODS

Six patients from our practice at Hacettepe University Hospitals, Ankara were included in this study. Subjects ranged in age from 3 to 21 at the time of surgery and follow up was from ten months to seven years. Three patients showed the motility characteristics of type 2 Duane’s retraction syndrome, two patients type 3 and one patient had abduction deficit of the right eye and both abduction and adduction deficit of the left eye. All patients demonstrated a variable face turn and an upshoot was present in all patients. They underwent motility surgery to eliminate the overshoot and the face turn.

3RESULTS

The right eye was affected in two patients, left eye in two and the other two had bilateral involvement. All of them had deviation in the primary position (range 12–60 pd, mean 33.67 pd) The method of surgery to treat upshoot was splitting of lateral rectus muscle into a Y configuration in five patients and lateral rectus muscle recession only in one patient. The splitting of the ends of the lateral rectus into a Y configuration resulted in improvement of the upshoot in all patients without any complications. Lateral rectus recession only had no effect on the upshoot.

4 DISCUSSION

Different types of surgical techniques are defined for the treatment of upshoot and downshoots in DRS. One of the effective techniques is the recession of the LR muscles. The amount of the

Table 1. Individual data of 6 patients who had surgery for upshoot and downshoot.

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recession can be defined according to the amount of LR tightness defined preoperatively by the forced duction test. Although a fibrotic LR can be recessed to 7–8 mm for the treatment of vertical deviation, a nonfibrotic LR must be recessed to 10–12 mm. The application of a posterior fixation suture with the recession of the LR also has resulted favourable results for the treatment of the upshoots.

Y splitting of the LR muscle is another surgical procedure for the treatment of the vertical deviation. LR recession can be added to splitting if the glob retraction in adduction is high.

According to Roger et al Y splitting first defined by Jampolsky in 1980 increases the vertical stabilization effect of the LR muscle over the glob. By application of the Y splitting technique the authors have treated all the head position, esotropia and the abnormal vertical movements in a 5

cases series.

In our series Y splitting of the LR was the preferred method for the treatment of the upshoots. 5 cases (83%) had Y splitting of the LR, 1 case (17%) had LR recession only. LR recession was added to four of the cases treated with Y splitting. The upshoot was decreased in all cases with the Y splitting surgery (%40 full correction) but it was unchanged in patients with LR recession surgery only. As Roger stated earlier addition of LR recession to Y splitting results in better outcomes if the presence of enophthalmos in adduction accompanies upshoot and downshoots.

Another method of surgery used for the treatment of the vertical movements is the vertical muscle recession. This technique is not favored by some surgeons because of high risk of postoperative iatrogenical vertical deviation. Mohan and Saroha applied SR recession to 10 patients with upshoot. They have observed that the upshoot was recovered in all patiens. Vertical rectus muscle recession was not applied for the treatment of DRS patients with the upshoot and downshoot phenomenon in our clinic.

Vertical muscle transposition suggested by Mohan, Saroha and Kraft is also not favored in our clinic for the treatment of upshoot and downshoot in DRS patients. Because the vertical rectus muscles innervated bythe 3rd nerve doesn’t compansate for the lateral rectus muscle innervation, therefore a full version movement is not expected. Vertical muscle transposition is not expected to compansate the real tight medial rectus muscle alone, therefore a MR recession must also be added to the surgery. However this addition may result in an over correction in the primary position and increase the anterior segment ischemia risk as 3 rectus muscles are involved in surgery.

5 CONCLUSION

The splitting of the ends of the lateral rectus muscle into a Y configuration is an easily performed operation which effectively improves the upshoot in patients with Duanes’ retraction syndrome. Performing simultaneous recession to the lateral rectus muscle combined with the splitting into Y configuration at its insertion improves the outcome, especially in patients with marked globe retraction.

REFERENCES

Bloom, Graviss, Mardelii. A magnetic resonance imaging study of the upshoot – downshoot phenomenon of Duane’s retraction syndrome. Am. J. Ophthalmol. 1972; 88: 635–639

Mohan, Saroha. Vertical rectus recession for the intervention of upshoot and downshoot in Duane’s retraction syndrome. J. Pediatric Ophthalmology and Strabismus 2002; 39: 94–99

Molarte, Rosenbaum. Vertical muscle transposition surgery for Duane’s syndrome. Journal of Pediatric Ophthalmology and Strabismus 1990; 27: 171–177

Rogers, Bremer. Surgical treatment of the upshoot and downshoot in Duane’s retraction syndrome. Ophthalmology 1984; 91: 1380–1382

Von Noorden, Murray. Up and downshoots in Duane’s retraction syndrome. Journal of pediatric ophthalmology and strabismus

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