Excisions Flashcards
What is the optimal apical angle (in degrees) for the vertices of a fusiform excision?
≤30 degrees (avoids formation of standing cons)
What is the optimal length to width ratio for an excision?
≥3:1
What is a crescent excision and what locations is it good for?
One side is longer than the other, leading to a curved line when closed. This good for areas with curved relaxed tension lines (cheek and chin)
What is a M-plasty and what is it useful for?
This is where on one side of the eclipse, instead of an elipse two small tringles extend from the circular central defect. When closed this looks like an “M.” Because the lines don’t extend all the way as a fusiform excision this is for shortening the scar
- Good for free margins like the perioral and periocular areas
What is an “S-plasty” what does it do to the length of the excision, and what is its use?
Increases the length of the scar (creates a lazy S shape) but the overall length (end to end) is the same. This redistributes the tension along different vectors and decreases tension in the central portion of the scar
- This decreases risk of a depressed scar and decreases risk of dehiscence and contraction
What locations tend to be good for a S-plasty?
Convex surfaces
Examples: forearm, shin, and excision that cross over a joint
When should a wedge excision be used on the lower lip?
Full-thickness excision of the lip for defects up to 1/3 the length of the lower lip
What must be marked prior to doing a wedge excision?
The vermillion border prior to closure!
This is a must to make sure the realignment is precise
What is the order of closing a wedge excision of the iip?
- Submucosal layer using silk or polyglactin 910 (bury knots away from oral cavity)
- Orbicularis oris muscle, use polyglactin 910 (maintains competence of oral sphincter
- Dermis and subcutaneous layers, use polyglactin 910 (start at the vermillion-cutaneous border)
- epidermis: Use nylon w/ hyper-eversion to prevent depressed scar
What are the options for repairing a standing cone?
Extend the incision, M-plasty, excision of a Burow’s triangle, rule of halves
What are the most common causes of standing cones (“dog ears”)?
Apical angles too wide (>30 degrees) length to width ratio too low (<3:1), unequal lengths on each side of the wound, convex surfaces, and insufficient undermining at the wound edge
What are 4 options for standing cone repair options?
- Extending the incision line
- M-plasty
- Rule of halves
- Excision of Burow-s triangle
In what plane should undermining occur in the trunk or extremities?
Mid-deep fat (for small/standard excisions)
Just above deep fascia for larger lesions/deeper melanoma
In general, what is the undermining plane on the face?
In general, undermining should occur superficially to the SMAS (superficial subcutaneous plan)
b/c motor nerves are in or deep to the SMAS usually
What is the optimal undermining plane on the cheek?
Mid subcutaneous plan (avoid transecting parotid duct, buccal and zygomatic branches of CN7, and vascular structures)
