Intercartilaginous Incision
By using a two-prong retractor, evert the caudal margin of the nostril and, by applying pressure with the middle finger of the nondominant hand, reveal the gap between the cau dal margin of the upper lateral and the cephalic margin of the lower lateral cartilages. With a scalpel, make an intercartilaginous incision in this location (Fig. 4) (1,2).
Figure 4. A-C: Intercartilaginous incision. D: For an intercartilaginous approach, bilateral intercartilaginous incisions are connected in the midline over the anterior septal angle, and the incision extends anterior to the caudal septum as a high partial-transfixion incision. Ex posure of the middle and upper nasal vault proceed as described in the text. E: After com pletion of the intercartilaginous approach, a Converse retractor (or other appropriate retrac tor) may be inserted through the incisions, beneath the skin/soft-tissue envelope, to provide exposure of the upper two thirds of the nose.
Marginal Incision
By using a two-prong retractor, evert the caudal margin of the nostril in which an inter-cartilaginous incision was made and, by applying pressure with the middle finger of the nondominant hand, define the caudal margin of the lower lateral cartilage. Pressing cephalad on the nasal dome will cause the caudal margin to appear laterally. Remember that the non-hair-bearing area is a guide to the caudal margin of the lateral crus. Furthermore, pal pation of the cartilage edge with the handle of the scalpel can be helpful before cutting. By using the two-prong retractor to obtain proper exposure, make the marginal incision just caudal to the caudal edge of the lower lateral cartilage (Fig. 5). Great care must be taken as the lateral incision nears the midline. Make sure that the incision follows the cartilage edge and does not take a "short-cut" along the alar rim, which can damage the facet area. Great care must be taken not to cut across a narrow dome or intermediate crux (1,2).
Figure 5. Marginal incision. The nondominant hand is critical to obtain proper exposure.
Delivery of lower lateral cartilages
At this stage, an intercartilaginous incision and marginal incision on one side and a transcartilaginous incision on the other side have been made. Reinsert the two-prong re-tractor into the nostril with the intercartilaginous and marginal incisions and present the caudal margin of the lower lateral cartilage with the aid of pressure from the third finger of the nondominant hand.
Use a slightly curved, fine-pointed dissecting scissors to lift and dissect the soft tissues from the surface of the lower lateral cartilage (Fig. 6). Perform this dissection by inserting scissors into the marginal incision laterally and then separate the perichondrium of the lower lateral from the overlying external skin and soft tissue with a spreading motion. If this is difficult, caudal traction on the vestibular skin underlying the lower lateral cartilage, with a tine two-prong hook, will facilitate this maneuver (Fig. 7) by pulling the lateral crus into the vestibule and thus opening up the potential dissecting plane. Avoid damaging the overlying muscle and nasal vasculature (1,2).
Figure 6. Dissect the soft tissues from the superficial surface of the lower lateral cartilage.
Do not work too far laterally. The lateral one fourth of the lower lateral cartilage should be avoided by the surgeon in nearly all cases.
Place the hook end of a Nievert retractor through the intercartilaginous incision and draw the now-free lateral crus down, like a visor, until it appears outside of the vestibule. It can be held in this position by the Nievert or by another suitable instrument (Fig. 8).
Examine the lower lateral cartilages for unique anatomic features and asymmetries.
Figure 7. Caudal traction on the vestibular skin underlying the lower lateral cartilage with a fine two-prong hook pulls the lateral crus into the vestibule and opens the potential dissecting plane.
Figure 8. Delivery of lateral crus of lower lateral cartilage.