Swelling Behind Ear and Nerve Regeneration

Dear Dr Yang

Hi its me again, I have recently in the last two weeks developed some fluid behind both ears between the incisions and the ear, the one on the right has much more fluid and it feels swishy to touch, Could this be a seroma and how can it be dealt with. Also over the past two weeks i have begun to feel exreamly tired just getting up is exhusting, I am unsure why this is, my GP is concerned and is doing various blood tests.

I am still concened about my mouth there is no inprovement in the lower lip and my speech is still affected, but i guess i need to give this time. Following you seeing my photos have you any idea why this occured which nerves are effected.

Thank you



Hi Suzy,

The first week after general anesthesia, it is frequently reported by patients that they have a weakness or tiredness which is different from their normal energy level. This does not happen to everyone, but is not uncommon. After a week this is usually gone. If you are having or still having low energy levels now, it is unlikely to be caused by the surgery. Facial surgeries in general do not lose much blood, so an anemia related to your surgery is unlikely. Since anemia and thyroid conditions occur in the normal population more frequently than people who have facelift surgeries, these and other diagnoses should be ruled out by your GP.

Swelling behind the ears
Most likely you have swelling behind the ears and not a seroma. I based this on the photos that you sent, which showed the pleating behind the ears, and appeared pretty flat. Since you are close to 2 month out after you surgery, if you did have a large hematoma or seroma, most likely it would have resolved already. Seromas are unlikely to form later on spontaneously.

Since skin surgery lifts up the skin off the underlying fat, the lymphatic drainage (the drainage system for extra swelling) is disrupted and can cause episodes of swelling long after the surgery (within the first year). The swelling may be worst in the mornings, when you are laying supine, or some people will get more swelling with exercise (for example.) The extra fluid that accumulates faster in the tissues than the healing drainage system can handle, and it backs up (overflows?) and causes swelling. As the lymphatic drainage system heals and drains better (over several months; everyone heals at different rates), these episodes become less frequent and eventually resolve.

What is a seroma?

A seroma is a collection of serous fluid under the skin. Blood is a combination of red blood cells and serum. One layman’s example of serum or serous fluid is when someone skins their knee (may not have much bleeding), but will have a clear yellow fluid that will crust and dry up on the surface of an abrasion. That’s serum.

A seroma acts like a bag of fluid under the skin. When you press on it, it acts like a small water balloon. It is compressible, and as you press on one side of the seroma, the other side bulges out because of the shift in fluid (very similar to a water balloon.)

How does a seroma typically form? In facelift surgery, a seroma typically forms after a hematoma. If the hematoma is drained, the skin did not get a chance to stick to the underlying tissues and will likely begin to collect the serum or serous fluid. If the seroma is left alone, it will eventually be absorbed by the body, but may take longer. I will decompress the seroma until the fluid collection is less than 5 cc’s. This 5 cc (one teaspoon) will be a small enough amount that the body can absorb this on its own without further help. With each decompression the amount usually halves. So if it is a large hematoma 60 cc’s is drained, usually only 30 cc’s may reaccumulate, then 15 cc’s then 7.5 cc’s, then 4 cc’s, then no further drainage. In women this may occur in about 1 in 20 to 1 in 30 patients. Usually these patients have a high blood pressure issues. In men the risk of hematoma is 5-7x’s higher than in women, due the the greater number of blood vessels needed to feed a man’s bearded facial skin.

Which nerve/muscle was injured? Why?

It looks like the marginal mandibular branch of the facial nerve base on your photos. The other nerves appear to be intact. The prognosis for a full recovery is very good. Most likely it is a heat injury of compression injury of the nerve, versus a direct cutting of the nerve, but only your surgeon would know the real answer.

How fast do injured nerves heal?

When a nerve is injured there is a degeneration of the nerve starting from where the nerve was injured. So nerve healing is not as easy as a reconnection of the cut or injured area of the nerve. Outer sheath of the nerve stays intact, but the electrical system (the wire) actually completely degenerates, then the “wire” has to grow 1-3 mm per day through the intact sheath until it connects to the muscle again. The distance from the back of the ear to your lip is about 15 cm or 150 mm, so it can take up to 150 days (about 5 months) for the muscle to start to show some movement. This is where the 4-6 month estimation for nerve healing to occur comes about. Since everyone can heal at different rates, there is some variability in the timing.

From Wikipedia:
If a nerve fiber is cut or crushed, the part distal to the injury (i.e. the part of the axon separated from the neuron’s cell nucleus) will degenerate, in a process known as Wallerian degeneration.[1] This is also known as anterograde degeneration.

Wallerian Degeneration occurs after axonal injury in both the peripheral nervous system (PNS) and central Nervous System (CNS). It occurs at the distal stump of the site of injury and usually begins within 24 hours of a lesion. Prior to degeneration distal axon stumps tend to remain electrically excitable. After injury, the axonal skeleton disintegrates and the axonal membrane breaks apart. The axonal degeneration is followed by degradation of the myelin sheath and infiltration by macrophages. The macrophages, accompanied by Schwann cells, serve to clear the debris from the degeneration.[2][3]

The nerve fiber’s neurolemma does not degenerate and remains as a hollow tube. Within 96 hours of the injury, the proximal end of the nerve fiber sends out sprouts towards those tubes and these sprouts are attracted by growth factors produced by Schwann cells in the tubes. If a sprout reaches the tube, it grows into it and advances about 1-3 mm per day, eventually reaching and reinnervating the target tissue. If the sprouts cannot reach the tube, for instance because the gap is too wide or scar tissue has formed, surgery can help to guide the sprouts into the tubes. This regeneration however happens only in PNS, not in the spinal cord. The crucial difference is that in the CNS, including in the spinal chord, myelin sheaths are produced by oligodendrocytes and not by Schwann cells.
Remember a watched pot never boils. How do you normally make tea? You know that it will eventually boil, so you walk away and do other things until you hear the kettle whistle or it is about enough time for it to boil and you go check the pot. Same analogy for your nerve regeneration.

Personal experience
I have tried to watch a water boil. My younger son is almost 1, so every night for the past year, it’s my job to boil the bottles and nipples before making all the bottles of formula. When I am in a rush, I will use hot water to hopefully get a headstart on boiling the water. But standing there waiting for the bubbles to form and for the water to boil seems like an eternity, yet looking at the time, it’s only been a couple of minutes. I can’t do it, nor is it a good use of my time to sit there and watch water boil. I have to walk away and check the computer or watch some news, and by the time I go back many times the water is already half boiled away.

Hopefully understanding the science behind it, you can now do the math. You have ~150 mm of nerve to connect at a rate of 1 mm/day, so don’t bother checking for about 5 months. If you don’t watch it, most likely one day you will realize that its already back and functioning.


Dr. Yang