Comparative Blink Analysis in Patients With Established Facial Paralysis Using High-Speed Video Analysis

This study analyzed the blink characteristics of patients with incomplete and complete facial paralysis. The authors measured and compared the palpebral distance, eyelid movement distance, and the eye-closing ratio of blinks in 55 patients with Bell's palsy or Ramsay Hunt syndrome (Bell & Hunt group) and 14 with complete paralysis (Complete Paralysis group). In the Bell & Hunt group, the palpebral distance (7.94 mm) was smaller on the paralyzed side than on the non-paralyzed side (9.61 mm). The eye-closing ratio and the upper eyelid movement were reduced on the paralyzed side (65.3% versus 93.7%, 4.61 versus 7.97 mm) and in the Complete Paralysis group (25.3% versus 94.7%, 2.10 versus 8.49 mm). In the Bell & Hunt group, movement of the upper eyelid on the paralyzed side was weakened despite palpebral contracture. The Complete Paralysis group exhibited highly reduced movement in both the upper and lower eyelids.