Upper eyelid ptosis repair after cataract extraction and the importance of Hering's test.

Blepharoptosis is a well-documented complication of cataract extraction and other ocular procedures. Few authors have described the surgical findings and outcomes of postcataract blepharoptosis repair. The authors present a review of the causes of postcataract blepharoptosis with emphasis on both clinical findings and recommendations for treatment on the basis of their experience with 13 eyelids in eight patients over the past 10 years. They found that all patients had either partial or total disinsertion of the levator muscle from the tarsal plate. Of the eight patients in this series, five had bilateral blepharoptosis after bilateral cataract extraction. Although a multifactorial cause for postcataract blepharoptosis is commonly assumed, the authors propose that the mechanical forces of intraoperative traction on the levator aponeurosis during cataract surgery are the primary cause. This is further supported by their operative findings in the five patients who developed bilateral ptosis after bilateral cataract extraction. All eyelids in this series were repaired by levator muscle advancement and attachment to the tarsal plate with favorable outcomes and no recurrences during a 1-year follow-up. The importance of Hering's phenomenon of equal innervation is also discussed as it applies to bilateral and to apparent unilateral blepharoptosis. The authors propose "Hering's test" as an important indicative study in the preoperative evaluation of all patients with eyelid ptosis.