ORIGINAL ARTICLE OCULOPLASTIC Histopathological Characteristics of the Orbicularis Oculi Muscle After Lower Blepharoplasty With or Without Myotomy S. Lessa 1 • J. Pontello 1 • R. Wanick 1 • E. Flores 2 • W. Costa 3 • F. J. Sampaio 3 Received: 4 October 2018 / Accepted: 28 December 2018 Ó Springer Science+Business Media, LLC, part of Springer Nature and International Society of Aesthetic Plastic Surgery 2019 Abstract Lower blepharoplasty is a challenging aesthetic procedure. Despite advances in clinical and neuroanatom- ical studies related to orbicularis oculi muscle innervation, no study has examined its histopathological aspects in different lower blepharoplasty procedures. This study aimed to assess changes in the pretarsal muscle complex in patients treated with transcutaneous lower blepharoplasty with orbicularis myotomy versus those treated with transconjunctival blepharoplasty without myotomy. Methods A total of 268 patients underwent blepharoplasty performed by a single surgeon: transcutaneous lower ble- pharoplasty in 112 (41.7%) and transconjunctival lower blepharoplasty with retroseptal access in 156 (58.2%). Subsequent minor blepharoplasty procedures were per- formed in 32 patients with lower pretarsal orbicularis oculi muscle biopsy. Connective tissue, fibrillar elastic system, nerves, blood vessels, fiber diameter, and sarcomeres were analyzed. Results Without myotomy: collagen, 9.46 ± 0.41%; elas- tin, 7.03 ± 0.62%; blood vessels, 4.25 ± 0.06%; nerves, 5.2 ± 0.55%; fiber diameter, 62 ± 8.0 lm; and sarcomere, 1.9 ± 0.11 lm. With myotomy: collagen, 19.02 ± 1.66%; elastin, 7.88 ± 1.10%; blood vessels, 5.13 ± 0.70%; nerves, 2.9 ± 0.48%; fiber diameter, 49 ± 6.5 lm; and sarcomere, 1.8 ± 0.17 lm. Discussion Excess endomysial connective tissue, particu- larly between muscle fibers, should be considered patho- logical. The pathological changes in the pretarsal muscle complex after blepharoplasty with myotomy may have resulted from innervation interruptions as well as vascu- larization blockages. Conclusions Surgeries with myotomy caused significant changes in collagen, nerves, and muscle fiber diameter. These observations strongly suggest the superiority of a technique that preserves orbicularis oculi muscle integrity. Level of Evidence III This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. Keywords Pretarsal orbicular complex Á Histopathology Á Myotomy Introduction Blepharoplasty is one of the most common cosmetic surgeries. According to the American Society for Aesthetic Plastic Surgery [1], it was the third most frequent proce- dure performed in 2017 in the USA. Despite its frequency, lower blepharoplasty is recognized as one of the most challenging aesthetic procedures. Numerous surgical techniques have been described, and there is no consensus in the literature of the ideal procedure to correct the structural changes associated with aging [2–10]. Historically two types of lower palpebral aesthetic procedures have been frequently employed: the anterior transcutaneous approach and the posterior transconjuncti- val approach. In the traditional transcutaneous technique, & S. Lessa s.lessa@alternex.com.br 1 Plastic Surgery Division, State University of Rio de Janeiro, Rio de Janeiro, Brazil 2 Department of Opthalmology, State University of Rio de Janeiro, Rio de Janeiro, Brazil 3 Urogenital Research Unit, State University of Rio de Janeiro, Rio de Janeiro, Brazil 123 Aesth Plast Surg https://doi.org/10.1007/s00266-018-01305-1