Related Experiment Video
Updated: Aug 24, 2026

Surgical Correction for Pediatric Epiblepharon and Trichiasis
Published on: July 8, 2025
A Morphologic Classification and Surgical Algorithm for Lower Eyelid Asymmetry in Primary Lower Blepharoplasty
Kenneth K Kim1,2,3, Jin Suk Byun4
1From the Division of Plastic and Reconstructive Surgery, University of California Los Angeles School of Medicine, Los Angeles, CA.
Background:
Lower eyelid asymmetry is common yet often overlooked. This study proposed a morphologic classification and surgical algorithm based on palpebro-malar groove width, anterior-posterior displacement of the inferior orbital rim, and lower eyelid vertical length. It evaluates outcomes based on this classification and algorithm, using sub-orbicularis oculi fat (SOOF) advancement and orbicularis oculi muscle suspension.
Methods:
From June 2023 to May 2025, 267 patients who underwent primary lower blepharoplasty were prospectively evaluated. Patients were categorized into 3 major types (5 subtypes) according to palpebro-malar groove width, posterior displacement of the inferior orbital rim, and lower eyelid vertical length. Surgical techniques were customized according to classification type. Postoperative outcomes were assessed using standardized clinical photography, independent evaluator review, and patient-reported satisfaction.
Results:
Among 267 patients (mean age, 56.8 y; 40 men, 227 women), 127 (48%) were type I (mild), 134 (50%) type II (severe), and 6 (2%) type III (right-side dominant). The left inferior orbital rim was positioned more posteriorly than the right in 96% (259 of 267). The left palpebro-malar groove was wider in 38%, whereas the right was wider in only 2%. Postoperatively, 251 patients (94%) reported satisfactory correction; 16 (6%) were partially satisfied, mainly due to inadequate lateral SOOF advancement. Independent evaluator assessment confirmed symmetry in 251 cases.
Conclusions:
Lower eyelid asymmetry reflects underlying midfacial skeletal discrepancies between the maxilla and zygoma. The proposed classification facilitates preoperative assessment and surgical planning. Algorithm-based SOOF advancement and orbicularis oculi muscle suspension were associated with improvement in lower eyelid symmetry in most patients.
Related Concept Videos
Accessory Structures of the Eye
Muscles of the Eye
Extraocular Muscles
The six extraocular muscles surround the eyeball and control its movements. They are responsible for a wide range of eye motions, including looking up, down, left, right, and rotating...

