Management of the Plunging Ranula

[Dr. Ashley Agan]
Yes. It just occurred to me that we jumped into the patient presentation before we talked about what is a ranula. You talked about your spiel to patients about what is a ranula? How does it plunge? Can you just tell us what your patient spiel sounds like?

[Dr. Rohan Walvekar]
Yes, absolutely. It's really difficult to describe to patients and so this is how I usually tell my patients about ranulas. I tell them that the sublingual gland is this small gland that contributes to less than 1% of saliva, but then, when it gets obstructed, or it gets injured for whatever reason, it can really be troublesome. I talk to them about it being tucked between the mandible on one side and the mandible is trying to elbow it in.

Then the other side is the muscles of the tongue that are really sandwiching this gland in the middle. When the glands gets obstructed, or it gets injured, it starts leaking saliva because it has nowhere to go. Saliva leaks out of this gland, because it's overcapacity, and now it's flowing into the floor of the mouth. I tell patients that saliva in its normal space in the mouth, in the digestive system, is very helpful, but outside of that, and we know that from our laryngectomy, fistulas, and things like that, it's very irritant.

I graphically tell them that if I take a syringe, fill it with saliva, and inject it into my muscles, what it's going to do is going to create an intense reaction. When saliva leaks out from the sublingual gland, the body tries to create a reaction around it, almost trying to shepherd it into trying to stop the saliva from going to different places, and that what that looks like is a pseudocyst. Basically, a wall of inflammatory cells that really don't have any integrity, but it's just a way for them to curb that infection.

If that's limited to the floor of the mouth, then you see a cyst in the floor of the mouth, but at some point in time, this is just a free-flowing water, it's like a leaking faucet and sometimes the fluid will find weaknesses in the floor to be able to escape into the neck. These tend to be the neurovascular ports in the mylohyoid muscle. You actually see these weaknesses, or these areas of dehiscence while you do level one neck dissection.

If you really pay careful attention to your level one neck dissection, as you take this fibrofatty packet of tissue out of level one, you'll see a lot of vasculature over the mylohyoid muscles. Guess what, that's exactly where the saliva is going to flow out of and come into the neck. I talk to them about that and say that once it's in the neck, it forms this plunging ranula, but the source is that leaking faucet in the floor of the mouth, which is the sublingual gland. I don't know if that's helpful.

[Dr. Gopi Shah]
No, I think that's wonderful. Thank you. That's really helpful.

[Dr. Ashley Agan]
That's the best explanation of a pseudocyst for me. Perfect.