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Clinical radiology quiz
Quixzes Am J Otolaryngol 10:36CL361,1969
Clinical
Radiology
Quiz
PETER M. SOM, EDITOR
A 3%year-old man presented with a mild ache in his left cheek of several weeks’ duration. He was otherwise in good health and had no other
Figure 1.
significant medical history. A plane film is shown (Fig 1). Based on this film, what is the most likely diagnosis?
Waters view of paranasal
360
sinuses.
CLINICAL RADIOLOGY QUIZ
DISCUSSION A diagnosis can be made from the plane film without further radiologic studies. The left antrum is opacified, minimally enlarged, and remodelled when compared with the right side. No bone erosion is seen. The remaining paranasal sinuses and the nasal fossae are normal. Based on these findings only, the differential diagnosis would include an antral mucocele, a large antral polyp, an antral inverted papilloma, or a rare antral tumor such as a lymphoma or pleomorphic adenoma, etc. However, there is one additional radiographic finding; the presence of a densely radio-opaque tooth in the medial wall of the left antrum! The only way a tooth could be so displaced as part of a cystic-expansile antral process is if it is part of an antral dentigerous cyst. Follicular cysts are subclassified as either primordial or dentigerous. The latter comprise 95% of follicular cysts and nearly 34% of all odonto-
genie cysts. Most present in the second and third decades of life. They arise from an unerupted tooth after the crown of the tooth has developed. As the cyst grows, it pulls the unerupted tooth with it. Radiographically, a small dentigerous cyst can be distinguished from a dental follicle. The normal dental follicle measures ~2 cm in greatest width. If the cystic component of the follicle is greater than this, it is likely that the tooth will never erupt and that a dentigerous cyst will develop. SUGGESTED READING Stafne EC. Gibilisco JA; Oral Roentgenographic Diagnosis, ed 4. Philadelphia, Saunders, 1975, pp 147-168 Verbin RS, Barnes L: Cysts and cyst-like lesions of the oral cavity, jaws, and neck, in Barnes L (ed): Surgical Pathology of the Head and Neck, volume 2. New York, Marcel Dekker, 1985, pp 1233-1329 Som PM: The paranasal sinuses, in Bergeron RT, Osborn AG, Som PM (eds): Head and Neck Imaging Excluding the Brain. St Louis, Mosby, 1984, pp l-142
Volume
10
Number September
5
1989 361
Clinical
Radiology
Quiz
PETER M. SOM, EDITOR
A 3%year-old man presented with a mild ache in his left cheek of several weeks’ duration. He was otherwise in good health and had no other
Figure 1.
significant medical history. A plane film is shown (Fig 1). Based on this film, what is the most likely diagnosis?
Waters view of paranasal
360
sinuses.
CLINICAL RADIOLOGY QUIZ
DISCUSSION A diagnosis can be made from the plane film without further radiologic studies. The left antrum is opacified, minimally enlarged, and remodelled when compared with the right side. No bone erosion is seen. The remaining paranasal sinuses and the nasal fossae are normal. Based on these findings only, the differential diagnosis would include an antral mucocele, a large antral polyp, an antral inverted papilloma, or a rare antral tumor such as a lymphoma or pleomorphic adenoma, etc. However, there is one additional radiographic finding; the presence of a densely radio-opaque tooth in the medial wall of the left antrum! The only way a tooth could be so displaced as part of a cystic-expansile antral process is if it is part of an antral dentigerous cyst. Follicular cysts are subclassified as either primordial or dentigerous. The latter comprise 95% of follicular cysts and nearly 34% of all odonto-
genie cysts. Most present in the second and third decades of life. They arise from an unerupted tooth after the crown of the tooth has developed. As the cyst grows, it pulls the unerupted tooth with it. Radiographically, a small dentigerous cyst can be distinguished from a dental follicle. The normal dental follicle measures ~2 cm in greatest width. If the cystic component of the follicle is greater than this, it is likely that the tooth will never erupt and that a dentigerous cyst will develop. SUGGESTED READING Stafne EC. Gibilisco JA; Oral Roentgenographic Diagnosis, ed 4. Philadelphia, Saunders, 1975, pp 147-168 Verbin RS, Barnes L: Cysts and cyst-like lesions of the oral cavity, jaws, and neck, in Barnes L (ed): Surgical Pathology of the Head and Neck, volume 2. New York, Marcel Dekker, 1985, pp 1233-1329 Som PM: The paranasal sinuses, in Bergeron RT, Osborn AG, Som PM (eds): Head and Neck Imaging Excluding the Brain. St Louis, Mosby, 1984, pp l-142
Volume
10
Number September
5
1989 361