Heavy eye syndrome versus sagging eye syndrome in high myopia

Abstract

Background Heavy eye syndrome (HES) presents with esotropia and limited abduction due to superotemporal globe shift relative to the extraocular muscles. Sagging eye syndrome (SES) was originally described in nonmyopic patients exhibiting distance esotropia and cyclovertical strabismus with limited supraduction due to lateral rectus muscle inferodisplacement caused by degeneration of the lateral rectus–superior rectus (LR-SR) band. We hypothesized that SES might also cause strabismus in high myopia. Methods Eleven strabismic subjects with high myopia underwent ophthalmological examination and orbital magnetic resonance imaging (MRI) to assess quantitative orbital anatomy. Results Of 11 subjects, 5 had HES; 6, SES. Mean axial length in subjects with HES was 32 ± 5 mm; in subjects with SES, 32 ± 6 mm. Average distance esotropia in subjects with HES was 61Δ ± 39Δ; hypotropia was 26Δ ± 21Δ. Average distance esotropia in subjects with SES was 23Δ ± 57Δ; hypertropia was 2Δ ± 2Δ. All 5 subjects with HES had superotemporal globe prolapse; the LR-SR band was thinned in 6 orbits and ruptured in 2. The mean angle between the lateral rectus and superior rectus muscles in HES was 121° ± 7°. In SES the LR-SR band was thinned in 7 orbits and ruptured in 5, with superotemporal soft tissue prolapse. The mean angle between the lateral rectus and superior rectus muscles was 104° ± 11°, significantly less than in HES (P < 0.001). Conclusions SES occurs in highly myopic patients who also exhibit less relative globe dislocation than in HES. Unlike HES, SES exhibits superotemporal soft tissue prolapse that may limit superotemporal globe shift. The distinction is important because surgery for HES uniquely requires creation of a surgical connection between the superior rectus and lateral rectus muscles, whereas SES may be treated with conventional surgery. SES can cause strabismus in high axial myopia. Orbital MRI is useful in differentiating SES from HES.

Decompensated Esophoria as a Benign Cause of Acquired Esotropia

“…Since the neurological and radiological investigations were unrevealing, and no neurological disorders emerged on follow-up, it is highly unlikely that brain lesions caused the AACE in the current series. Young patient age, normal adnexal examination findings, absence of hypotropia, absent deep superior orbital sulci, and unremarkable MRI of the extraocular muscles and orbital tissues exclude the possibility of heavy eye and sagging eye syndromes in our patients 24,25 .…”

Mechanical optic neuropathy in high myopia

“…Disorders such as heavy eye syndrome have been reported and associated with pathological myopia on the basis of the idea that the longer, more myopic eye is in a relatively low position, as though it was too heavy. The causation appears to be an abnormally low muscle path of the lateral rectus in the involved eye, provoking hypophoria or hypotropia . The relative volume of osseous and soft tissue orbital structures may affect the protrusion of orbital contents and the vital space for the intraorbital optic segment.…”

Magnetic Resonance Imaging of the Globe-Tendon Interface for Extraocular Muscles: Is There an “Arc of Contact”?

“…Imaging demonstrates age-related dehiscence of the LR pulley suspension from the SR 17–19 . The LR pulley slides inferotemporally around the globe, changing the LR direction of force from directly temporal to inferotemporal.…”

“…Abnormalities in the position and strength of the posterior functional anatomy of the rectus muscles, such as the heterotopic pulleys found in craniosynostosis syndromes and other anatomic disorders that create pattern strabismus 14–16 or the sagging lateral rectus (LR) EOM path that occurs with age 17, 18 or high myopia to create acquired esotropia and hypotropias 19, 20 , have been well described and analyzed. Abnormalities in the anterior EOM anatomy have also been described, although the emphasis has been on incomplete or imperfect re-attachment after surgical repositioning 21, 22 rather than the thickness and angle of tendinous attachment.…”