Monocular elevation deficiency (or “double elevator” palsy) is a descriptive term denoting a congenital deficiency of monocular elevation that is equal in abduction and adduction (1,2). In general, it can be paretic or restrictive, with reduced Bell phenomenon, normal upward saccadic velocities, and a prominent lower eyelid fold in the affected eye considered to be positive signs of inferior rectus contracture (3,4). We describe a child with monocular elevation deficiency who displayed tethering and buckling of the central lower eyelid in downgaze. We caution that this manifestation of inferior rectus contracture can simulate impaired infraduction in the involved eye.
A 4-year-old boy was referred to us for evaluation of an inability to elevate the right eye since birth. He was born prematurely at 28.5 weeks gestation, weighing 2 lb 13 oz, and required hospitalization for 3 months. He was currently meeting his developmental milestones.
On examination, visual acuity was 20/25, right eye, and 20/20, left eye, using Allen cards. He maintained fixation with the left eye but did not do so with the right eye. Extraocular movements showed absent elevation of the right eye in primary position and right and left gaze. Mild right upper eyelid pseudoptosis was noted, which resolved with fixation of the right eye. An enhanced right lower eyelid fold was present. Titmus stereoacuity was 60 seconds of arc. Fixing at near, he had 5 prism diopter right hypotropia, which was horizontally comitant but increased to 25 prism diopter in upgaze and resolved in downgaze. Upward saccades from infraduction to primary position were brisk in the right eye. Bielschowsky head tilt testing produced no detectable change, and Bell phenomenon was diminished in the right eye. The patient maintained a slight chin-up head position when viewing objects of interest. There was no associated jaw winking, and retinal examination showed mild extorsion in both eyes. Cycloplegic refraction was +1.75 +2.00 × 15° in the right eye, and +1.25 +0.50 × 175° in the left eye. He was prescribed glasses and treated with part-time occlusion therapy of the left eye.
On his follow-up visit, his findings were unchanged except that version testing showed what appeared to be deficient downward rotation of the right eye compared to the left eye (Fig. 1). However, prism and alternate cover testing showed no hyperdeviation in downgaze. On closer examination, it became apparent that the mid portion of the right lower eyelid had tethered and buckled in downgaze, producing retraction of the right lower eyelid. The greater visibility of the right lower iris created the appearance of an infraduction deficit of the right eye (Fig. 1). This focal eyelid retraction was attributed to contracture of the right inferior rectus muscle.
In 1977, Scott and Jackson (4) described an accentuated lower eyelid fold that became more prominent in attempted upgaze as a sign of inferior rectus contracture in children with monocular elevation deficiency or “double elevator palsy.” In our patient, an accentuated lower eyelid fold in upgaze was accompanied by focal tethering and buckling of the lower eyelid in downgaze, creating the appearance of an infraduction deficit in the involved eye. If not recognized as a correlative sign of inferior rectus contracture, this unusual clinical manifestation could lead to unnecessary neurodiagnostic evaluation.
1. Metz HS
. Double elevator palsy. Arch Ophthalmol. 1979;97:901-903.
2. Brodsky MC
. Pediatric Neuro-Ophthalmology. New York, NY: Springer, 2010:348-350.
3. Ziffer AJ
, Rosenbaum AL, Demer JL, Yee RD. Congenital double elevator palsy: vertical saccadic velocity utilizing scleral search coil technique. J Pediatr Ophthalmol Strabismus. 1992;29:142-149.
4. Scott WE
, Jackson OB. Double elevator palsy: the significance of inferior rectus restriction. Am Orthopt J. 1977;27:5-10.