Ranjith K Puligadda*
Ranjith K Puligadda, Department of ophthalmology,NRI academy of sciences,Guntur, India
Received: 17 October, 2014; Accepted: 18 February, 2015; Published: 20 February, 2015
Ranjith K Puligadda, Department of ophthalmology,NRI academy of sciences, Guntur, India, Tel:91-9704075473; Email:
Puligadda RK (2015) Surgical Planning for Duane Retraction Syndrome. J Clin Res Ophthalmol 2(2): 019-025. DOI: 10.17352/2455-1414.000012
© 2015 Puligadda RK. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Globe retraction; Esotropia; Exotropia; Upshoots; Downshoots
PD: Prism Diopters; ET: Esotropia; XT: Exotropia; MR: Medial Rectus; LR: Lateral Rectus; OU: both eyes; SR: Superior Rectus; IR: Inferior Rectus
Introduction: Duane retraction syndrome (DRS) a type of relatively rare type of restrictive strabismus.
Methods and results: Six cases of DRS comprising of all sub types and their outcome was discussed simultaneously explaining how to plan surgical treatment for each component of DRS in each case. Horizontal, vertical deviations, abnormal head position, globe retraction and upshoots /downshoots were correctable in all cases of DRS.
Conclusion: Satisfactory surgical results can be achieved by operating cases of DRS with individualized surgical planning.
Duane retraction syndrome comprises a group of motility disturbances in which the common feature is co-contraction of medial and lateral rectus muscles on attempted adduction of the involved eye(s). Abnormal clinical features associated with DRS include horizontal deviation in primary position, abnormal head position, retraction of the globe on attempted adduction leading to pseudoptosis, up shoot and/or down shoot in attempted adduction, amblyopia, A,V and X patterns and various ocular and systemic anomalies can also occur. The syndrome is bilateral in 10% to 20% of cases.
Electromyographic (EMG) and saccadic velocity studies suggest that abnormal firing of lateral rectus is responsible for the globe retraction and pseudoptosis on attempted adduction. Neuropathologic studies confirmed that in at least some patients with DRS there is co-innervation between lateral rectus and extraocular muscles innervated by the third cranial nerve. In the two patients studied, the abducens (sixth cranial) nucleus was absent or hypoplastic and the lateral rectus innervated by a branch of inferior division of third nerve.
The etiology of the upshoots and downshoots has been ascribed by many authors to mechanical factors, specifically a "leash" or "bridle" effect of a tight lateral rectus (with or without a tight medial rectus) side slipping over the globe. There is evidence however for innervational factors, involving coinnervation of vertical rectus muscles with the lateral rectus that may contribute to the upshoots or downshoots in some patients. An approach to the surgical treatment of DRS is presented based upon the analysis of four important anomalies observed in this group of disorders:
• Primary position alignment
• Abnormal head position
• Severity of retraction
• Pattern of upshoot and downshoot and accompanying A, V or X pattern
By examining these features in each case an individualized surgical plan usually can be devised to yield the best possible results. Selected case examples will illustrate the benefits of this approach which the author has used to treat DRS.
Materials Methods and Results
Horizontal alignment in primary position
The primary position alignment in DRS can be orthotropic, esotropic (ET), or exotropic (XT) [1,2]. In some cases, a hypertropia may occur in addition to the horizontal deviation [3,4].
Duane Syndrome with ET (Table 1), the cases of unilateral DRS with ET almost always have deviations less than 30 prism diopters (PD). In cases of ET, part of the surgical plan should include a recession of the medal rectus of the eye with DRS [2,4]. This is particularly important if positive forced duction to abduction is present due to a contracture of the muscle (Figure 1).