Introduction: The lower eyelid is often the site of basal cell carcinomas, with Mohs micrographic surgery (which allows precise histological control with maximum tissue preservation) being the ideal method for their treatment. Tumors that invade the posterior lamella cause full-thickness defects of the lower eyelid, for which several reconstruction techniques have been described with composite grafts. However, few authors use the helix of the ear as a donor area. Objective: To describe the applicability of ear helix composite grafts in the reconstruction of the lower eyelid. Methods: Retrospective study of a series of 6 cases of basal cell carcinoma in the lower eyelid, with tarsal invasion, operated through Mohs micrographic surgery in a private specialist service in the city of Rio de Janeiro, Brazil. All patients had full-thickness defects, and had undergone reconstruction of the posterior lamella through chondroperichondrial graft of the ear helix. The anterior lamella was reconstructed with the remaining eyelid tissue mobilization or with an advancement flap. Patients were assessed for functional capacity and aesthetics. Results: There was complete adaptation of the perichondrium to the conjunctiva, after contact with the eyeball for 8 weeks. All patients with mild escleral show without ectropion. Conclusions: Despite the small sample, all patients had excellent cosmetic and functional results.

Keywords: EYELID NEOPLASMS; CARCINOMA, BASAL CELL; MOHS SURGERY; EAR CARTILAGE.

Introduction: Due to the risk of invasion of the orbital cavity and involvement of noble structures, the periocular region requires specific knowledge related to the anatomy and biological behavior of tumors in this region. Objective: To present the particularities and complexity of the approach to periocular tumors, through the analysis of cases treated at a Mohs micrographic surgery specialist center. Methods: A retrospective, observational, cross-sectional study was carried out based on data collected through a review of medical records, operative records, and photographic archives. Thirty-four cases were analyzed between April 2010 and April 2014. Results: Thirty-one basal cell carcinomas, two squamous cell carcinomas, and one sebaceous carcinoma were operated. Of these, 22 (64.70%) were primary tumors, and 12 (35.29%) were recurrent or incompletely excised. The nodular was the most common type of basal cell carcinoma (38.70%), followed by the micronodular (25.80%), the infiltrating (22.58%), the sclerodermiform (6.45%), the superficial (3.22%) and the adenoid (3.22%). Most of the lesions affected the lower eyelid (44.11%), followed in number by the internal canthus (41.17%), the upper eyelid (11.76%), and the external canthus (2,94%). There was only one recurrence following Mohs micrographic surgery. Conclusions: Most tumors had an aggressive histological subtype, especially those located in the internal canthus. Despite the study's limitations, the strict histological control of Mohs micrographic surgery, combined with the multidisciplinary approach to patients, provided excellent oncological, functional, and cosmetic results.

Keywords: MOHS SURGERY; CARCINOMA, BASAL CELL; CARCINOMA, SQUAMOUS CELL; EYELID NEOPLASMS; ORBIT EVISCERATION.