Biaxial serial excision: A technique to deal with benign skin lesions and scars

Abstract

Background:

In the best of hands, the ultimate surgical scar of an otherwise well-performed surgery is unpredictable, and surgical techniques are constantly evolving to prevent or revise large scars. The present series uses the principles of serial excision to reduce the eventual scar length.

Materials and Methods:

Between January 1991 and December 2010, 30 patients were operated upon. In the first stage, a lesion was reduced in two dimensions with the intent to create a smaller lesion with the long axis favourably placed. The residual lesion was then excised after 4 weeks or more.

Results:

The resultant scars were smaller and better aligned, with an excellent skin match.

Conclusion:

A well-planned serial excision in a biaxial manner helps reduce the final scar.

INTRODUCTION

Surgical scars are unpredictable in the hands of the most competent of surgeons, and newer techniques are evolving to avoid large scars. Laparoscopic surgeries, endoscopic brow lifts, thread lifts and liposuction are but a few examples. This is because no scar can match virgin scar-free skin that has not been incised. One such technique for scar revision is the use of serial excisions for the excision of a large lesion[1] or even the removal of a bald patch.[2,3] Serial excisions are usually performed to reduce the stretch in one direction. An ellipsoid of an involved lesion or scar is excised and the edges are brought together. At a later date when the surrounding skin and soft tissues have stretched sufficiently, the rest of the lesion can be excised and primary closure achieved. If this principle is used judiciously, two-dimensional reduction in the size of the lesion can be achieved. In addition, it is possible to align the lesion in such a way that the final scar can be placed favourably. This leads to a scar which is comparatively smaller and better aligned than before, with less tension on the final suture line, making it more pleasant and acceptable.

MATERIALS AND METHODS

From January 1991 to December 2010, 30 patients with nevi, tattoos or scars consented to biaxial serial excision to reduce the scar length. Representative cases are shown in Figures 1a, 2a, 3a, 4a, 5a and 6a. The smallest lesion was 7 × 8 mm over the upper lip philtrum and the largest was 20 × 55 mm.

Figure 1.

(a) A trapezoid tattoo on the forehead with possible designs of Limberg's flap. The inner marking is for the first stage of serial excision. (b) Residual lesion following excision, stage 1. (c) Stage 2, post excision final scar

Figure 2.

(a) An oval scar over the right cheek. (b) The outer marking of the scar and the inner markings for a biaxial excision, to reduce the size of the lesion in two dimensions. (c) The residual lesion at the end of the 1st stage. (d) Following the second stage excision. (e) The final result. The scar is well aligned with RSTL and there is no distortion of the lower eyelid

Figure 3.

(a) A large nevus on the chin, this was the first case done on 31 January 1991. (b) Serial excision 1st stage, the central lesion is excised and the edge within the residual lesion is further excised with multiple ‘v’s, which can be gathered to reduce the size of the lesion. (c) After the triangular defects are closed with purse string closure, the size of the residual defect is the same as the central lesion removed. (d) The length of the scar following second stage, almost the same as the original lesion. An Elliptical incision primarily would have extended the scar almost to the lip

Figure 4.

(a) Mole on the philtrum. Elliptical incision would have crossed the white roll and deformed the shape of the philtrum and the cupid's bow. (b) The residual defect following a biaxial serial excision and the change of direction of the scar. c) The final result. No distortion of the philtrum, cupid's bow, white roll

Figure 5.

(a) Nevus left temporal area. Elliptical single stage excision would leave a long scar, with a pull on the lateral eyebrow. (b) Biaxial serial excision, the residual lesion. (c) The final result

Figure 6.

(a) Another lesion over the chin, with the marking of an ellipse for primary excision and reconstruction. Note the possible length. (b) Following a biaxial excision, within the lesion. (c) After a purse string closure, the residual lesion. (d) The final scar length is almost the same size as the long axis of the lesion

Surgical technique

The lesion is mapped and outlined with a marker. A pattern is created within this boundary [Figures 1a and 2a] so that rather than a simple elliptical design within the lesion, the edges of the ellipse are extended outwards into multiple ‘w's or ‘v's [Figures 3b and 6b]. When excised this creates multiple triangular defects on the border of the main defect or lesion. At times, these cuts are strategically placed so as to change the direction of the long axis of the residual lesion to align it with relaxed skin tension lines for future alignment of the final scar. After achieving proper haemostasis, the lesion is closed from deep to superficial aspect with purse string sutures [Figure 3c] using PDS, Ethilon or Vicryl. Usually, one or two layers of purse string sutures are sufficient. The last but one is a subcuticular stitch gathering all the edges of the ‘w's or ‘v's. The skin is then closed with running or interrupted 5-0 or 6-0 Prolene, taking care not to cross the boundary of the lesion. This makes the residual lesion much smaller in size [Figures 1b, 2c, 3c, 4b, 5b and 6c].

After an interval of 4-6 weeks in smaller lesions and 3-6 months in larger lesions, the remaining lesion is excised [Figures 2d, 3d and 6d]. The resultant scar is smaller, well aligned and under less tension [Figures 1c, 2e, 4c and 5c].

RESULTS AND OBSERVATIONS

All the scars were smaller in length [Figures 1c, 2e, 3d, 4c, 5c and 6d] compared to the hypothetical primary elliptical excision of the entire lesion with the removal of dog ears. Most could be oriented along the relaxed skin tension line (RSTL). The stretch and distortion of the important anatomical landmarks were absent [Figures 1c, 2e and 4c]. The scars were also finer, at times almost imperceptible, and there was no cross-hatching of suture marks.

DISCUSSION

An unfavourable scar is a plastic surgeon's nightmare. Occasionally, despite surgical skill, an ugly scar destroys an otherwise well-performed surgery. Even when scars heal well, thin, shiny lines are left behind. At times patients come to a plastic surgeon with a demand to eliminate scars completely. The complete disappearance of a scar, however, is rarely, if ever, achieved. At best, a well-blended imperceptible scar is achieved. Experience, of more than a century of scar formation, has taught us that there is no fool-proof technique to make scars invisible. Unexpectedly, depressed or hypertrophic scars, keloids, thin stretched scars, shiny scars, dyspigmented scars, adherent, rough or uneven scars appear now and then, despite the best efforts of a proficient surgeon. Any technique, therefore, that can lead to a reduction in scar length is always useful.

Multiple partial excisions of wide defects were first advocated by Morestin,[4] Davis[5] and Sisrunk[6] about 90 years ago. In today's world of demand for quick fixes, the procedure of serial excisions with its need for time, multiple surgeries and additional costs has obvious disadvantages over single stage surgeries. None the less, the benefits of serial excision are worth considering.

With serial excisions, advantage is taken of the ability of both the skin and soft tissue to stretch and creep[7,8] over a period of time. With biaxial serial excisions, this is achieved in two different axes. After the first excision, the resultant lesion is smaller than the original in both the ‘x’ and ‘y’ axes. The neighbouring skin and soft tissue advance due to the relaxation and creeping phenomenon. After sufficient time when the skin around the lesion appears lax, the second stage is carried out. As the lesion has now become smaller, a smaller ellipse is required to be excised. A serial excision in one dimension also reduces the lesion width, without reducing the length in the other axis. Serial excision in one dimension may or may not allow reorienting the axis of a lesion in a more favourable position. However, in both cases, a serial excision done either in a uniaxial or a biaxial manner, the tension at the final suture line is much less than it would have been if it had been closed primarily following a complete excision of the lesion during the first surgery. This is so especially with regard to the central tightness at the widest point of an elliptical defect. The phenomenon of cross-hatching of the suture line, which occurs in case of closure under tension, also reduces due to reduced tension. Further, there are much smaller dog ears resulting in the eventual length of the scar being smaller. At times in a biaxial serial excision, the length could be the same as or even smaller than the longitudinal axis of the original lesion.

During planning and execution, the anatomic landmarks obviously need to be considered to avoid distortion. Since, the skin of the adjacent areas comes together there is no problem of colour or texture mismatch. There is an obvious advantage in serial excision as it reduces the requirement for flaps, especially in defects not amenable to primary closure. This avoids extra scars in adjacent noticeable areas, as well as distortion, for example, of the face. It also reduces the use of skin grafts with its attendant problems of colour mismatch, blending, shine, surface irregularity, edge thickening, donor site scarring, etc., The major drawback of this surgery is that it requires at least two stages and many patients may not agree to the additional cost of the surgery and the time it takes. Also, this technique may not work in conditions where the skin envelope is very tight, for example, a large lesion over the nose, which may cause distortion and therefore need alternate techniques. Ultimately, the technique is limited by the laxity of the surrounding skin, age of the patient, anatomic landmarks and the site of the lesion (e.g., nose, eyelids, fingers or hand). The areas over or near the joints may lead to distortions due to tightening or reduced mobility and result in stretched or hypertrophic scars. The surgeon needs to consider all these along with the size of the lesion before choosing this technique.

Biaxial serial excision takes advantage of the ability of the skin and soft tissue to stretch and creep in two axes. It gives a much smaller lesion in both axes, compared to a uniaxial serial excision, thereby achieving a better reduction in tension and scar length. This technique can be advantageous when used on the face, the most visible part of the body, as shown in the examples here. As such, it helps improve the quality of life as unsightly facial scars can be a lifelong source of depression. Besides the face this technique can also be used anywhere on the body.

In conclusion, biaxial serial excision provides an efficient method for reducing the length and aligning the eventual scar. When there is a demand for a better cosmetic appearance and a small scar, this technique may offer a useful option.