xRead - Facial Reconstruction Following Mohs Micrographic Surgery

Reconstruction of the Nose

49

bilobe flap ( Fig. 6 ). Next, a suture is passed full thickness from the alar vestibular mucosa through the external skin at the previously marked point. The suture is then used to precisely draw greater and lesser arcs from the far periphery and the cen ter of the defect, respectively. The distance be tween the lesser and greater arcs is rechecked using a caliper, which should be equal to the radius. Attention is next focused on marking the primary and secondary lobes of the flap. The pri mary lobe width is equal to the diameter of the defect, whereas the secondary lobe is generally slightly smaller. The primary and secondary lobes may be drawn with either squared or curved edges. The primary lobe height fits within the greater and lesser arcs, whereas the secondary lobe extends to be approximately twice this height. The axis of the primary and secondary lobes of the flap should form an approximately 45 angle. The axis of the secondary lobe and the center of the defect should form an approxi mately 90 angle. A standing cutaneous cone may be anticipated along the base of the defect. Local anesthetic is infiltrated into the entire nasal soft tissue envelope. After performing the skin inci sions along the previously outlined flap, wide undermining of the flap is performed deep to the nasal musculoaponeurotic layer, superficial to the perichondrium of the nasal cartilages and the periosteum of the nasal bones. Because the area of the greatest tension is along the secondary lobe, the secondary defect is first closed with a 5-0 monofilament absorbable deep dermal suture. The primary lobe is next transposed into position

scars are situated at the periphery of the subunit, slight wound contraction does not result in an un favorable aesthetic outcome, because it contrib utes to natural convexity within the subunit. There are several reconstructive approaches that may be considered and are discussed later. The final reconstruction plan should be deter mined based on patient preference as well as indi vidual patient factors. Nasal bilobe flap The bilobe flap is a local flap that is oftentimes considered a workhorse for nasal defect recon struction. Generally, the bilobe flap is selected for defects that are less than or equal to 1.5 cm in size, although this can vary somewhat depend ing on the quantity of nasal skin available for recruitment. The modification of the bilobe flap as described byZitelli 20 is the most common modern technique used for reconstruction of nasal defects. With the Zitelli technique, the angle formed between the axis of the primary defect and the axis of the sec ondary lobe is approximately 90 , which results in a smaller standing cutaneous cone when compared with the classic design. 20 The base of the bilobe flap may be positioned either laterally or medially depending on the reconstructive need. The surgical technique begins with measuring the radius of the defect. 8 A point is then marked with a fine skin pen near the alar groove approxi mately one radius from the periphery of the defect. This point forms the axis of rotation. Alternatively, the flap may be designed as a medially based

Fig. 6. A1.2 1.3-cm defect of the right nasal tip and lower sidewall. ( A ) Design of medially based nasal bilobe flap. ( B ) Completed closure of defect. ( C ) Postoperative result 5 months following bilobe flap and 2 months following dermabrasion.