Introduction:
Tornwaldt cyst, also known as Thornwaldt cyst or nasopharyngeal cyst, is a leftover bit from the notochord. It is usually small and often found by accident on an MRI (magnetic resonance imaging). If it grows big, it can cause nose, ear, or neck problems. Infections or injuries to the area often cause it. Surgery may be needed if it is causing symptoms, no matter their size.
What Is Tornwaldt Cyst?
Thornwaldt cyst is a growth located between the longus capitus muscles, with a diameter of at least 7 mm, and without any signs of inflammation in nearby soft tissues or involvement of adjacent bones. These cysts are harmless, often found by chance in the middle of the nasopharynx. When these cysts cause symptoms, it is known as Tornwaldt disease. These cysts develop early and usually do not cause symptoms. They are usually discovered by chance during imaging tests of the nasopharynx, so the age of diagnosis depends on when the imaging is done. Most cases are found in people aged 15 to 60, likely due to fluid buildup in the cyst over time.
What Causes Tornwaldt Cyst?
When the pharyngeal bursa gets blocked, a Tornwaldt cyst forms. This bursa sits above the superior pharyngeal constrictor muscles, around the level of the fossa of Rosenmuller. It stretches between the longus capitis muscles up to the occipital tubercle (a small bump on the base of the skull). Blockage at the opening of the bursa in the nasopharynx leads to the formation of the Thornwaldt cyst.
About 75 percent of cases involve trauma to the nasopharynx from conditions like nasopharyngitis, chemoradiation, or adenoidectomy.
What Are the Clinical Features of the Tornwaldt Cyst?
Tornwaldt cysts usually do not exhibit any signs or symptoms. But getting infected might lead to bad breath (halitosis) or sometimes release bad-tasting fluid into the mouth. In some cases, they can also cause ear infections because they block the eustachian tube.
Other clinical findings commonly reported in cases of Tornwaldt cysts are mentioned below:
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Cervical pain, stiffness, and vertigo were the main complaints.
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These symptoms were caused by muscle spasms in the neck due to the cyst.
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Nasal symptoms were not the main issue in this case.
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Large cysts can cause problems like stuffy noses, ear aches, and neck pain. They often occur because of repeat infections or injuries to the area.
What Is the Pathology of Tornwaldt Cysts?
Tornwaldt cysts develop in two forms: crusting and cystic. They originate from the retraction of the notochord, where it intersects with the endoderm of the primitive pharynx. This process typically occurs around the 10th week of embryonic development.
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Types: Closure at the orifice leads to the cystic type, while crusts adhering to the orifice without closure result in the crust type.
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Characteristics: The cyst is lined by respiratory epithelium and accumulates fluid with variable proteinaceous content. Inflammation can occur due to obstruction.
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In rare instances, Tornwaldt cysts have been reported to form following concurrent chemoradiotherapy for nasopharyngeal carcinoma.
How Can Tornwaldt Cyst Be Diagnosed?
During a simple diagnostic nasal endoscopy, a smooth submucosal mass can be observed along the roof of the nasopharynx. Usually, mass is found in the middle, but sometimes it can be off to the side. Even if it is not blocked, it might be hard to see the opening of the cyst. If there is any uncertainty, imaging tests can confirm the diagnosis.
MRI is the best way to find the cyst, check its size, what is inside it, and how it is positioned among nearby structures. Sure, signs seen on an MRI can help tell these cysts apart from other severe problems in the nasopharynx. MRI is also helpful in ensuring no extensions into the brain.
On CT (computed tomography) scans, these cysts show up as clearly defined areas with low density, often filled with fluid in the center. They do not light up with contrast. If the fluid has lots of protein, it might appear brighter and look like a solid mass.
Imaging Characteristics
Imaging studies depict well-circumscribed, thin-walled, rounded lesions immediately beneath the mucosa. These cysts exhibit variability in size, ranging from a few millimeters to several centimeters in diameter, with a typical size falling between 2 and 10 mm (millimeters). MRI imaging reveals clearly defined, thin-walled cysts displaying high signal intensity on T2 sequences without enhancement upon Gadolinium administration.
What Is the Treatment for Tornwaldt Cyst?
If the Tornwaldt cyst does not cause symptoms, no treatment is necessary. However, if it does cause symptoms, surgery can be used to remove it or create an opening to drain it. In such cases, surgical removal or marsupialization of the cyst through a transnasal approach is sufficient. This surgical approach often wholly resolves the symptoms for most patients. The procedure can be performed using a nasal endoscope and a microdebrider. Only using aspiration usually results in the cyst coming back. Surgical options for Tornwaldt cyst may include the following:
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Endoscopic Marsupialization: This minimally invasive procedure involves using an endoscope to access the nasopharynx, remove the cyst, or create a drainage opening to alleviate symptoms.
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Excision: In some cases, particularly for larger cysts or those in difficult-to-access areas, surgical excision may be performed through the nose (transnasal) or mouth (transoral).
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Laser Ablation: Laser therapy may shrink or destroy the cyst, particularly for smaller cysts or as an adjunct to other surgical techniques.
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Cyst Drainage: In cases where the cyst is infected or contains pus, drainage may be performed to relieve symptoms and prevent complications.
Conclusion:
The Tornwaldt cyst is a harmless lump filled with fluid that forms in the back wall of the nose. Doctors are still unsure about what exactly causes it. The cyst can be easily identified using a nasoendoscopy or imaging tests, confirmed by checking tissue samples. However, it is usually found by chance, and an MRI is the best way to prove it. It helps identify the cyst, assessing its dimensions, content, and spatial relationship with adjacent structures. After surgery, patients are monitored for a long time, showing that it is safe and effective, with no cyst returning for up to three years. Even though it is not common, doctors should consider this cyst in anyone with these symptoms and treat it accordingly.
