Abstract
Although Teflon has been used for almost 5 decades to provide tissue augmentation in various surgical indications, including head and neck surgery, its use has significantly declined in the last 2 decades, primarily because of its implication in granuloma formation. Teflon granulomas have been shown to cause false positives on positron emission tomography imaging and have been reported to have a characteristic magnetic resonance imaging (MRI) appearance. We report a patient with a large chronic Teflon granuloma of the parapharyngeal space that caused significant bony erosion of the atlas vertebra. The lesion’s MRI signal characteristics were indistinguishable from those of surrounding tissues, while it showed characteristic hyperdensity on computed tomography due to the presence of fluorine atoms within Teflon. As MRI may supersede or replace computed tomography for a number of indications, and as Teflon has been used in large numbers of patients whose records may not always be available, knowledge of these findings has clinical relevance.
1
Introduction
Teflon has been used to provide tissue bulk in many surgical indications for about 50 years . In otolaryngology, Teflon injections have been performed primarily in paralyzed vocal cords and into posterior parapharyngeal soft tissues to treat velopharyngeal insufficiency, an uncommon condition known as patulous eustachian tube, and, rarely, after tumor surgery . Although Teflon felt is still widely used in surgery to help with microvascular decompression and neurosurgical microdissection , injections of large amounts of Teflon have significantly decreased since the early 1990s after it was demonstrated that those commonly resulted in foreign body granulomas with giant cells and intense inflammatory reactions . Teflon granulomas may cause mass effect and other significant symptoms and may cause false-positive positron-emission tomography findings . Parapharyngeal Teflon granulomas have been reported to be characteristic on magnetic resonance imaging (MRI) and confusing on computed tomography (CT) . We report a patient with a large parapharyngeal Teflon granuloma, the MRI characteristics of which were exactly similar to those of the normal surrounding musculature while the CT appearance was far more specific.
2
Case report
A 57-year-old man presented with the chief complaint of right neck fullness and occasional right otalgia. The patient had a right masticator space schwannoma surgically resected 20 years prior and had been reoperated on 12 years prior for tumor recurrence involving the pterygoid muscles. Physical examination showed a prominent lateral process of the hyoid bone, otherwise normal neck and parotid gland palpation, and no evidence of recurrent tumor. Facial nerve function, vocal cord, and tongue mobility were normal. Magnetic resonance imaging of the neck, requested to evaluate for possible recurrent masticator space schwannoma, revealed a large right parapharyngeal mass with ill-defined margins, extending from the right fossa of Rosenmuller to the right longus capitis and colli muscles, with significant erosion of the anterior cortex of the right lateral mass and anterior arch of the atlas ( Figs. 1 and 2 ). The MRI characteristics of the mass were identical to those of the surrounding parapharyngeal tissues and muscles on T1, T2, and postcontrast T1-weighted sequences. MRI showed no recurrent tumor, expected postsurgical changes from a prior transparotid transcervical approach, and minor fluid accumulation in the right mastoid air cells consistent with right eustachian tube dysfunction. Two weeks later, the patient was brought back for a CT scan of the neck. Computed tomography confirmed smooth erosive changes of the right lateral mass of the atlas and showed that the parapharyngeal mass was hyperdense. Further review of the patient’s history revealed that Teflon had been injected in the patient’s parapharyngeal space at the time of his second surgery to treat velopharyngeal insufficiency secondary to tumor removal. The patient was reassured and treated conservatively.
2
Case report
A 57-year-old man presented with the chief complaint of right neck fullness and occasional right otalgia. The patient had a right masticator space schwannoma surgically resected 20 years prior and had been reoperated on 12 years prior for tumor recurrence involving the pterygoid muscles. Physical examination showed a prominent lateral process of the hyoid bone, otherwise normal neck and parotid gland palpation, and no evidence of recurrent tumor. Facial nerve function, vocal cord, and tongue mobility were normal. Magnetic resonance imaging of the neck, requested to evaluate for possible recurrent masticator space schwannoma, revealed a large right parapharyngeal mass with ill-defined margins, extending from the right fossa of Rosenmuller to the right longus capitis and colli muscles, with significant erosion of the anterior cortex of the right lateral mass and anterior arch of the atlas ( Figs. 1 and 2 ). The MRI characteristics of the mass were identical to those of the surrounding parapharyngeal tissues and muscles on T1, T2, and postcontrast T1-weighted sequences. MRI showed no recurrent tumor, expected postsurgical changes from a prior transparotid transcervical approach, and minor fluid accumulation in the right mastoid air cells consistent with right eustachian tube dysfunction. Two weeks later, the patient was brought back for a CT scan of the neck. Computed tomography confirmed smooth erosive changes of the right lateral mass of the atlas and showed that the parapharyngeal mass was hyperdense. Further review of the patient’s history revealed that Teflon had been injected in the patient’s parapharyngeal space at the time of his second surgery to treat velopharyngeal insufficiency secondary to tumor removal. The patient was reassured and treated conservatively.
