An excision provides a more extensive sample of a lesion that is too large for a shave or a punch biopsy.
The margins of submitted tissue can be examined for possible involvement (e.g., basal cell carcinoma, squamous cell carcinoma, and melanoma).
It often affords a definitive cure for many benign and malignant lesions.
The operator should be familiar with the underlying and surrounding anatomy.
A thorough approach to sterile technique is necessary: sterile gloves and sterile drapes should be used.
To achieve the best cosmetic results, place the lines of incision in or parallel to the relaxed skin. This placement is demonstrated by observing wrinkle lines and the effect of pinching the skin.
Once a direction for the long axis of the ellipse has been chosen, draw an ellipse using gentian violet or a surgical skin marker around the lesion before administering a local anesthetic. This approach minimizes tissue distortion.
Make sure that the excision has a length-to-width ratio of at least 3:1 and that the apices are at a 30-degree angle.
Anesthetize the area by local infiltration with lidocaine and epinephrine 1:100,000.
Use a no. 15 scalpel blade to make the incision. Use the dominant hand with the index finger and thumb of the other hand placed on either side of the incision. This pushes the skin under tension downward and away from the scalpel (Fig. 35.16A).
Start the incision using the point of the scalpel held in a vertical position at the apex of the ellipse. Use the belly of the scalpel along the side of the ellipse to elongate the incision (Fig. 35.16B).
Obtain an optimal tissue sample for histologic examination. The scalpel should cut through the upper subcutaneous fat so that the specimen includes the full thickness of the skin.
Dissect the tissue free of the underlying fat after making incisions on both sides of the ellipse. Use forceps with teeth to hold the apex of the skin being removed.
If the defect is large, dissect (undermine) the ellipse by using curved, blunt-tipped scissors (e.g., Steven tenectomy or Gradle scissors), making certain that the plane of the dissection is at the same level throughout. Undermining allows for the mobilization of tissue so that it can be advanced to close the defect; it also allows skin edges to come together with less tension and allows eversion of the wound edges with suturing (Fig. 35.16C).
To perform undermining, use blunt-tipped scissors while elevating the skin edge by forceps with teeth or a skin hook.
Advance scissors to the desired degree and open them to stretch the underlying skin. If necessary, repeat this procedure several times to achieve the desired skin mobility for wound closure.
Remove any remaining tissue septa using the open blades of the scissors.
Undermining is most effective when performed at the level of superficial fat tissue. This reduces the possibility of injury to nerves and blood vessels in the facial and neck areas.
Wound repair is facilitated if an adequate ellipse has formed, the edges are perpendicular to the skin, and skin lines are followed.
Meticulous hemostasis must occur after undermining. Apply direct pressure or perform electrocoagulation (Fig. 35.16D).
Place subcutaneous sutures after undermining, to allow approximation of the edges of the wound to close the wound (Fig. 35.16E).
Wounds should be closed in layers (Fig. 35.17A-B).
The closure of dead space is necessary when large, subcutaneous vacuities have been created, such as after removal of subcutaneous cysts.
Dermal, buried sutures are important on areas of the body that overlie large muscle groups, such as the upper trunk.
Obtain hemostasis (a “dry field”) before initiating wound closure.
Choice of suture material depends on the size and degree of tension on the wound and the location on the body.
For closure of the dermis and deeper subcutaneous layers, absorbable sutures such as polyglactin 910 (Vicryl) or polyglycolic acid (Dexon) are used. Absorbable sutures are fully absorbed and do not require removal.
For surface closure of the skin, nonabsorbable sutures such as nylon (Ethilon) or polypropylene (Prolene) are used.
For the face and cosmetically sensitive areas, smaller diameters such as 5-0 or 6-0 sutures are recommended. For the limbs or trunk, and areas with greater tension, larger 3-0 or 4-0 sutures are required.
Monocryl is an absorbable suture that is very easy to handle and has excellent tensile strength. It causes little tissue reaction and thus is most often used when minimal tissue reactivity is essential.
The method of “halving” is the most effective technique for wound closure. “Halving” allows for equal distribution of wound tension (Fig. 35.17A).
Apply an occlusive dressing (a perforated plastic film or sheet with an absorbable pad) or pressure dressing, if necessary, to prevent postoperative bleeding (Fig. 35.17B).
Suture removal depends on wound tension, location, and depth of placement.
Generally, removal of facial sutures should occur in 5 to 7 days and removal of sutures on the trunk should be in 1 to 2 weeks.
Outline