Inservice Exam - 2005
Cosmetic Face Lifts

Which of the following layers of the scalp is analogous to the SMAS layer?

(A) Deep temporal fascia
(B) Galea
(C) Innominate fascia
(D) Parotid-masseteric fascia
(E) Pericranium

The correct response is Option B.

The galea is analogous to the SMAS layer because the galea-frontalis, temporal parietal fascia, SMAS, orbicularis oculi, and platysma form a continuous single layer. Awareness of this anatomic relationship is essential to avoiding injury to the facial (VII) nerve during dissection for a facelift and browlift. The nerve lies just under the layer of the SMAS, facial muscles, and galea.
The deep temporal fascia, innominate fascia, parotid-masseteric fascia, pericranium, and cervical fascia are all part of an analogous, deeper anatomic grouping beneath the more superficial SMAS system.


References:
1. Thorne CHM, Aston SJ. Aesthetic surgery of the aging face. In: Aston SJ, Beasley RW, Thorne CH, eds. Grabb & Smith’s Plastic Surgery. 5th ed. Philadelphia: Lippincott Williams & Wilkins; 1997:636.
2. Williams PL, Warwick R, Dyson M, et al, eds. Gray’s Anatomy. 37th ed. New York: Churchill Livingstone, 1989:570-573.



A 54-year-old woman has had inability to depress the right side of the lower lip for the past month. This symptom began shortly after she underwent subcutaneous rhytidectomy with SMAS plication along with submental suction lipectomy. Which of the following is the most appropriate next step in management?

(A) Exploration of the surgical site for possible transection of a nerve
(B) Follow-up examination in one month
(C) Marginal mandibular nerve grafting
(D) Physical therapy with nerve stimulation
(E) Temporalis muscle transfer to the right oral commissure for facial reanimation


The correct response is Option B.


Because nerves generally are not severed during rhytidectomy, SMAS plication, and suction lipectomy, this patient=s deficit is most likely the result of neurapraxia. With neurapraxia, function normally returns spontaneously within three months. Therefore, a follow-up examination in one month is the most appropriate step at this time.

Because the facial (VII) nerve travels deep to the muscles of facial animation, rhytidectomy with dissection in the subcutaneous plane does not pose a risk to the facial nerve branches. Deeper dissection can be more dangerous and should be performed with a clear understanding of the anatomy of the facial nerve. The frontal branch of the facial nerve becomes very superficial as it crosses the zygomatic arch. The other branches become superficial as they exit from within the parotid gland. SMAS surgery superficial to the parotid gland is generally safe. The anterior edge of the parotid gland lies no less than 3.5 cm from the tragus. Submental suction lipectomy is also very safe and poses minimal risk if the cannula stays superficial to the platysma. If the cannula passes beneath the platysma, the marginal mandibular branch of the facial nerve is at risk. Large studies of patients who have had suction lipectomy have shown a low rate (<1%) of nerve injury. Nerves and blood vessels are generally not severed during suction lipectomy.

Physical therapy with nerve stimulation is not necessary because nerve function will return spontaneously. Surgical exploration is not warranted because of the very low probability that the nerve has been severed.

Marginal mandibular nerve grafting and temporalis muscle transfer are not indicated for facial reanimation because the deficit is likely to improve spontaneously. Also, temporalis muscle transfer to the right oral commissure would help elevate the commissure but not depress the lip.
References:
1. Dellon AL. Peripheral nerve injuries. In: Georgiade GS, Riefkohl R, Levin LS, eds. Georgiade Plastic, Maxillofacial, and Reconstructive Surgery. 3rd ed. Baltimore: Williams & Wilkins; 1997:1011-1013.
2. Dillerud E. Suction lipoplasty: a report on complications, undesired results, and patient satisfaction based on 3511 procedures. Plast Reconstr Surg. 1991;88:239-246.
3. Wilhelmi BJ, Mowlavi A, Neumeister MW. The safe face lift with bony anatomic landmarks to elevate the SMAS. Plast Reconstr Surg. 2003;111(5):1723-1726.




A 56-year-old woman has a 3-cm area of preauricular skin slough 10 days after undergoing sub-SMAS rhytidectomy. Which of the following interventions is the most appropriate initial management?

(A) Observation
(B) Debridement
(C) Flap advancement
(D) Full-thickness skin grafting
(E) Split-thickness skin grafting
The correct response is Option A.

After rhytidectomy, skin slough requires careful observation. The injured skin forms an eschar that should be left in place until it begins to separate. The separated eschar may be trimmed as the wound epithelializes, which may take three to four weeks.

The other interventions are not needed initially. Debridement is indicated if infection develops beneath the eschar. Skin grafting is used only for large areas of slough that do not close in a reasonable period of time. After skin laxity has returned, scar excision and flap advancement may be indicated to improve the appearance of the scar.

References:
1. Rees TD, Aston SJ, Thorne CHM. Blepharoplasty and facialplasty. In: McCarthy JG, May JW, Littler JW, eds. Plastic Surgery. Vol 4. Philadelphia: WB Saunders; 1990:2358-2435.
2. Rees TD. Postoperative considerations and complications. In: Rees TD, ed. Aesthetic Plastic Surgery. Philadelphia: WB Saunders; 1980:708-727.