What Is a Ranula?
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What is a Ranula?
A ranula (derived from the Latin word for “little frog”) is a mucous cyst that can develop under your tongue. Mucous cysts often form due to a local injury, such as lip biting or eating a sharp piece of food.
A ranula is different from other oral mucous cysts because it occurs under your tongue. Ranulas (or ranulae) can be large and are filled with fluid because a salivary gland is blocked.
Most ranulas are “simple,” meaning they’re confined to the floor of your mouth. You’ll usually only notice them when your mouth is open. But occasionally, the swelling will be visible in your neck (this is referred to as a cervical or plunging ranula).
What are the Symptoms of a Ranula?
A ranula typically appears as a translucent blue dome and may fluctuate in size. It’s often seen on one side of the mouth rather than in the middle.
Aside from the obvious appearance, ranulas often don’t cause noticeable symptoms. They’re generally only painful if they become infected.
However, an especially large ranula could push your tongue upwards and make it difficult to swallow or breathe. Ranulas can also quickly shrink or rupture on their own and then begin to swell again.
You should seek medical care if you or your child have a ranula that is persistent, recurring, or especially large. A doctor or dentist can provide effective treatment to eliminate the swelling and prevent the ranula from recurring.
How is a Ranula Diagnosed?
To diagnose a ranula, your doctor or dentist will want to physically examine the affected area. They’ll take note of the color, shape, and texture of the swelling to help distinguish it from other lesions, such as a dermoid cyst or branchial cleft cyst.
To confirm the diagnosis, your doctor may also order an ultrasound, MRI, or CT scan. They’ll also want to rule out other causes by checking for additional symptoms.
Can a Dentist Diagnose a Ranula?
Yes, dentists can generally diagnose and treat a ranula. An ear, nose, and throat doctor (otolaryngologist) can also address the issue. Ranulas are one of the most common salivary gland disorders.
What Causes a Ranula?
Ranulas are generally caused by an injury to a salivary gland, typically a sublingual gland. The ducts these glands use to release saliva are delicate, and a sharp object or piece of food can damage them.
When a salivary duct is damaged, it can’t drain saliva into your mouth the way it normally would. This causes it to leak into the surrounding connective tissue.
The buildup of saliva, combined with the thickness of the affected tissue, can make a ranula large enough to fill the floor of your mouth.
Certain genes may increase the likelihood of developing or being born with a ranula. For example, ranulas seem to be more prevalent among Pacific Islander populations.
How is a Ranula Treated?
Treatment for a ranula, if necessary, will depend on how large, persistent, or symptomatic it is. The following are the most common treatment approaches.
Salivary Gland Removal
The usual treatment for a ranula is surgical removal of the blocked salivary gland. This prevents the cyst from returning.
Alternatively, a radiologist can perform a procedure called needle aspiration or ablation. This involves injecting the damaged salivary gland with a specific medication, causing it to shrivel and become scar tissue.
Both procedures take a few weeks to heal from. You may have pain and swelling in the area as it heals. In the case of ablation, you might experience numbness on the floor of your mouth for about a month after the procedure.
Marsupialization
Another method of treatment is called marsupialization. A small incision is made in the cyst and then sutured at the edges to bring the inner and outer surfaces together. This allows it to drain freely while keeping the salivary gland intact.
This procedure will also take some time to heal from, but it’s less involved than completely removing the affected gland.
No Treatment
Small ranulas that don’t cause problems may be left to dissipate on their own. The affected gland may be able to function normally afterward.
However, if the ranula swells up again, one of the treatments above may be required.
Can a Ranula Lead to Complications?
While a ranula is rarely a cause for serious concern, it can have some unpleasant complications if left untreated, such as:
- The site becoming infected, which could be painful and require additional treatment
- Repeated injury due to the size of the ranula
- Difficulty swallowing (dysphagia), breathing (dyspnea), or chewing food
- The ranula continues to burst and reform periodically
Don’t attempt to pop a ranula at home. Attempting to pop a ranula on your own could contribute to these complications. Proper treatment will help you avoid them.
Ranula Prevention and Outlook
There isn’t any sure way to prevent a ranula. They’re most common in children and young adults. In rare cases, babies are born with them.
However, using caution with sharp objects or pieces of food will make you less likely to injure your mouth. Maintaining good oral hygiene will also reduce your risk of an oral infection.
Ranulas can be treated effectively in almost all cases, and severe complications are rare. Recovery from ranula ablation or surgery can take a few weeks.
Summary
A ranula is a type of dome-shaped cyst (or mucocele) that sometimes appears on the floor of the mouth. It’s caused by a damaged salivary gland, usually one of the sublingual glands that can’t drain saliva properly.
Ranulas are most common in children and adolescents, and an oral injury is often to blame. In some cases, children are born with a ranula.
Treatment usually involves removing the offending gland. However, it’s sometimes possible for the cyst to be drained or left to resolve on its own. Seek medical attention if you or your child have a large or persistent ranula.
What Is A Ranula?
NewMouth PodcastSources
- Huzaifa, Muhammad, and Abhinandan Soni. "Mucocele and Ranula." StatPearls, 2022.
- Boulos, Mark I. "Case 1: What is that in your mouth?" Paediatrics & Child Health, 2006.
- Dayton, Kristin, and Matthew F. Ryan. "Symptomatic Floor-of-Mouth Swelling with Neck Extension in a 14-Year-Old Girl." Case Reports in Pediatrics, 2014.
- La’Porte, Sarah, et al. “Imaging the Floor of the Mouth and the Sublingual Space.” RadioGraphics, 2011.
- Chung, Y.S., et al. "Comparison of outcomes of treatment for ranula: a proportion meta-analysis." British Journal of Oral and Maxillofacial Surgery, 2019.
- Kusano, Yusuke, et al. "Treatment of oral ranula in HIV-positive patient." Auris Nasus Larynx, 2021.
- Kokong, Daniel, et al. "Ranula: Current Concept of Pathophysiologic Basis and Surgical Management Options." World Journal of Surgery, 2017.
UCLA-trained dentist practicing in public health. Focuses on whole-body approach to dental care.
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