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Loss of vertical palpebral fissure height on downgaze in acquired blepharoptosis
1Department of Ophthalmology, Sinai Hospital, Detroit, Mich., USA.
Objective:
To determine criteria to diagnose and document functional visual impairment from upper eyelid ptosis in the downgaze position of reading.
Design:
Prospective clinical study.
Patients:
From September 1991 to June 1992, 47 consecutive patients with adult-onset acquired ptosis were enrolled in the study. Downgaze eyelid and relative brow position were evaluated in 88 eyelids of these patients.
Interventions:
Surgical repair of blepharoptosis by the Müller muscle conjunctival resection ptosis procedure, levator aponeurosis advancement and/or resection, or levator muscle resection.
Main Outcome Measure:
Postoperative change in the eyelid and brow position in downgaze.
Results:
Of all ptotic eyelids, 43% had zero vertical palpebral fissure height in downgaze when the brows were relaxed and therefore were functionally blind in the downgaze position. After ptosis repair, there was a significant widening of the vertical palpebral fissure height in downgaze (P < .001), a significant decrease in frontalis muscle use (P < .001), and return of the patients' ability to sustain downgaze function.
Conclusions:
Measurement of palpebral fissure height in downgaze and frontalis muscle use in patients with acquired ptosis identifies patients with a functional visual deficit in the downgaze reading position. These measurements can be easily performed in the office and may be added to criteria for documenting functional impairment from blepharoptosis.
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