In 1985, Burget and Menick's landmark article on the nasal subunit principle popularized the technique of reconstructing the specific topographic subunits that they identified as the dorsum, tip, and columella and the paired alae, sidewalls, and soft triangles. In patients with more than 50 percent of subunit loss, Burget and Menick proposed removing the remaining portion of the subunit and reconstructing the entire subunit with a skin graft or flap. They further supported the placement of incisions for local flaps along borders of aesthetic subunits to maximize scar camouflage. Although the concept of nasal subunits is important in planning the reconstruction, other aesthetic considerations, such as skin texture, color, contour, and actinic damage, are also crucial in achieving an optimal result. Often, focusing on these aspects with the goal of nasal symmetry in mind leads to the violation of the subunit principle but provides a pleasing result of both the defect and the donor site. The purpose of this study was to demonstrate when and how the modification of the nasal subunit principle is used to achieve coverage of nasal skin defects. A retrospective analysis of patients who underwent nasal reconstruction after skin cancer ablation surgery by one surgeon at the Hospital of the University of Pennsylvania from 1987 to 2000 was performed. During this 13-year period, 219 patients underwent 245 nasal reconstructions. Seventy-four patients with 76 reconstructions (31 percent) had procedures that violated the classic nasal subunit principle. Eight of these 74 patients (11 percent) had complications, and eight (11 percent) had 10 revisions performed. The aesthetic and functional results were graded as excellent, good, and fair. The results for the 74 patients who underwent modification of the subunit were excellent in 85 percent, good in 13 percent, and fair in 2 percent. Case reports were selected to illustrate situations in which the nasal subunit was altered.

The OMENS system represents the most comprehensive, versatile, objective, and easily adaptable attempt at clinical classification of hemifacial microsomia to date. The authors propose a concise clinical evaluation form using a modified version of the system to promote the use of the OMENS system, to aid in the evaluation of hemifacial microsomia patients, and to assist in data sharing among academic institutions.