Nasal Reconstruction After Mohs Surgery
The nose is a common area to have skin cancer. Because of it’s position on the face, it is subjected to a significant amount of skin exposure. There are many factors to consider when reconstructing the nose after Mohs procedures including:
- The size of the defect
- Cosmetic concerns
- If the defect involves the cartilage and/or the internal lining of the nose
Mohs Reconstruction Approaches
There are two main schools of thought when reconstructing defects of the nose. One option is to repair only the existing defect that was left by the Mohs surgery, referred to as the defect only approach. The second option is referred to as a subunit repair. In this approach, the nose is divided anatomically into nine subunits. A defect in any of the nine subunits requires removal and repair of the entire subunit. The concept is that, aesthetically, it will look better if an entire subunit looks the same and the subunit will blend in better than having a patch of skin replaced wherever it is missing.
It is possible to obtain satisfactory results using either approach and certain approaches may be more appropriate in certain areas of the nose. For example, it may be more beneficial to use a subunit approach when reconstructing the lower third of the nose as opposed to the upper two thirds. In addition, the size of the defect and desires of the patient must all be taken into consideration. Each repair must be evaluated and planned on an individual basis.
Structures That Need To Be Replaced
When determining what type of reconstruction is required, a surgeon must determine what elements need to be replaced. Of course, the skin will always be missing, but what about the cartilage and skin on the inside of the nose (nasal lining)? If the cartilage and/or lining of the nose need to be replaced then the repair becomes more complicated. However, in the hands of an experienced Mohs reconstruction surgeon, satisfactory results can still be achieved on a routine basis.
It is important to understand the extent of the defect and the reconstructive options available when determining how a defect will be reconstructed. The techniques for cartilage and nasal lining repair are beyond the scope of this post. An interesting article on nasal reconstruction including cartilage and nasal lining reconstruction was published in Seminars of Plastic Surgery (https://www.thieme.com/books-main/plastic-surgery/product/2164-seminars-in-plastic-surgery) and can be found here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2884875/pdf/sps22257.pdf
Tissue Repair Techniques
Depending on the size, location, and cosmetic desires of the patient, there are three main categories of tissue repair: skin graft, adjacent tissue transfer, and regional tissue transfer.
Skin Grafts used to reconstruct a properly sized and positioned defect may provide aesthetically pleasing results. Skin grafts are usually taken from the skin in front or behind the ear or from the forehead depending on where the graft will be placed. The upper portion of the nose is typically more amenable to skin grafting than the lower one third of the nose is. Small (less than 1 cm) defects of the lower third of the nose may be candidates for skin grafting. Secondary procedures such as dermabrasion may be required in order to achieve the desired aesthetic result.
Adjacent Tissue Transfer
When skin grafts are not felt to be appropriate, the next step in the reconstruction algorithm is to elevate local tissues creating a “flap” and then use plastic surgical techniques to rearrange the tissues so that they cover the nasal defect while leaving an inconspicuous scar where the flap was raised.
Several examples of adjacent tissue transfer techniques can be found on our Mohs reconstruction page. Examples of various rearrangement techniques are shown below:
Regional Tissue Transfer
Lastly, when the defect is too large to be reconstructed using adjacent tissues, regional tissues must be brought into the area. In nasal reconstruction, this usually requires the use of forehead tissues. Typically regional tissue transfers require multiple stages. In the case of a “forehead flap”, the forehead tissue is lifted and re-positioned over the nasal defect while it remains connected to its blood supply from the forehead (see image above). Unlike a small thin skin graft that can survive on the nasal defect without it’s own blood supply, a large and much thicker regional flap requires it’s own blood supply to survive. Therefore, the forehead flap remains connected to its original blood supply until it has developed a new blood supply from the nasal tissues. Once the flap has developed it’s own new blood supply from the nose, its attachment with the forehead can then be removed and it will survive in its new position with its new blood supply. It can take four weeks or longer for the forehead flap to develop its new blood supply in the nasal area.
Reconstruction of nasal defects after Mohs surgery can result in a pleasing aesthetic result. Nasal reconstruction is complicated with a lot of factors to consider. A Mohs reconstruction surgeon with extensive experience is required to choose the correct reconstructive technique for each patient and to be able to technically perform the procedure. For more information regarding Mohs reconstruction please visit our Mohs Reconstruction page.