J Korean Soc Radiol.  2013 Oct;69(4):287-293. 10.3348/jksr.2013.69.4.287.

Differential Points of Mediastinal Cystic Lesion in Chest Computed Tomography

• Lee SJ
• Baek JM
• Song JH
• Park SY
• Seon HJ
• Kim YH

• KMID: 2041949
• DOI: http://doi.org/10.3348/jksr.2013.69.4.287

Abstract

PURPOSE
To find differential diagnostic imaging findings of mediastinal cystic lesions in chest computed tomography.
MATERIALS AND METHODS
We retrospectively reviewed imaging findings of 70 patients with histopathologically proven mediastinal cystic lesions. They were 33 male and 37 female patients.
RESULTS
Among 70 cases, 49 cases were in the anterior mediastinum, 12 cases were in the middle mediastinum, and 9 cases were in the posterior mediastinum. 19 patients had symptoms. Chest discomfort was the most common symptom. When the cystic lesion was located in the anterior mediastinum, and unilocular, the possibility of thymic cyst was the most likely (p < 0.0027). When the cystic lesion was located in the anterior mediastinum and was multilocular with a relatively thick wall, the possibility of a mature cystic teratoma was the most likely (p < 0.001). When the lesion was a high attenuation cystic lesion located around the air-way, the possibility of a bronchogenic cyst was the most likely (p < 0.001).
CONCLUSION
Chest CT gives information about the location, loculation, wall thickness and internal attenuation of mediastinal cystic lesions. And certain details seen on CT imaging can help with the correct diagnosis, especially in the cases of thymic cyst, mature cystic teratoma and bronchogenic cyst.

MeSH Terms

Bronchogenic Cyst
Diagnostic Imaging
Female
Humans
Male
Mediastinal Cyst
Mediastinum
Retrospective Studies
Teratoma
Thorax

Figure

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  Fig. 1 Mature cystic teratoma in a 23-year-old man who had chest discomfort. Contrast enhanced CT scan shows a heterogeneous anterior mediastinal mass with areas of fat (arrow), calcification (long arrow), and fluid attenuation.

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  Fig. 2 Mature cystic teratoma in a 43-year-old female with a history of chronic cough. Contrast enhanced CT shows multiloculated cystic mass in anterior mediastinum without fat nor calcification. It has thick and smooth enhancing wall (arrow).

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  Fig. 3 Bronchogenic cyst in a 25-year-old man with a history of neck pain. Contrast material-enhanced CT scan shows a cyst with uniform high attenuation (42 Hounsfield unit) with an imperceptible wall. It is abutting trachea on right side (arrow).

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  Fig. 4 Thymic cyst in a 76-year-old asymptomatic man. Contrast enhanced CT scan shows a thin-walled water attenuation cyst in anterior mediastinum.

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