대한흉부영상의학회 Weekly Chest Cases

Case No : 133 Date 2000-05-13

Courtesy of Kyung Soo Lee, M.D. / Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea
Age/Sex 48 / F
Chief ComplaintIncidental abnormality on routine chest radiograph

Figure 1
Figure 2
Figure 3
Figure 4

Diagnosis With Brief Discussion

Diagnosis: Bronchogenic Cyst (Mediastinal type)
Radiologic Findings: Chest radiograph shows a well-defined, contour-bulging shadow in the left paraspinal region, overlapped with the aortic arch shadow.
Contrast-enhanced CT scans show a little-enhancing, low attenuation mass in left paraspinal region.
On surgery, a well-defined cystic mass was found in the posterior mediastinum.
Brief Review: Bronchogenic cysts are congenital lesions resulting from abnormalities in ventral budding or branching of the bronchopulmonary foregut.

The lesions have been classified as mediastinal and intrapulmonary types.

Mediastinal cysts are far more frequent and do not communicate with the bronchial tree, unlike intraparenchymal cysts in which such communications usually develop, leading to frequent recurrent infection.

Most bronchogenic cysts are most commonly located in the carinal area (52%), followed by paratracheal area (19%), esophageal wall (14%), and retrocardiac area (9%).

These cysts rarely can be seen in other locations such as the anterior mediastinum, the low posterior mediastinum, or in the lung itself.

Their classic chest radiographic findings are clearly defined round or oval masses of water density, commonly located just inferior to the carina.

These thin-walled cysts are lined with respiratory epithelium and cyst fluid is composed primarily of water admixed with varying amounts of thick proteinaceous mucus. Calcium oxalate crystals have also been detected in the fluid.

This variable fluid composition explains the different CT attenuations observed in bronchogenic cysts.

Usually, CT of bronchogenic cyst shows a mass with the same attenuation as that of water, reflecting their serous nature.

However, in one-half of all bronchogenic cysts, the CT density can vary from a low soft-tissue range to higher-than-muscle density, likely due to intracystic hemorrhage, protein, or calcium.

Those patients who are asymptomatic and have small cysts with typical CT findings can be followed. If a malignant neoplasm is suspected because CT findings are atypical or the mass has increased in size, surgery or aspiration may be required for diagnosis and treatment.
References: 1. Nakata H, Nakayama C, Kimoto T, et al. Computed tomography of mediastinal bronchogenic cysts. J Comput Assist Tomogr 1982;6:733-738
2. Naidich DP, Zerhouni EA, Siegelman SS. Computed tomography and magnetic resonance of the thorax. 2nd ed. Philadelphia: Raven Press, 1991:120-123
3. Glazer JS, Siegel MJ, Sagel SS. Low-attenuation mediastinal masses on CT. AJR 1989;152:1173-1177
4. Mendelson DS, Rose JS, Efremidis SC, Kirschner PA, Cohen BA. Bronchogenic cysts with high CT numbers. AJR 1983;140:463-465
Keywords: Mediastinum, Congenital,

No. of Applicants : 50

▶ Correct Answer : 39/50, 78.0%

- 媛怨
- 嫄곗갹
- 寃쎈 議곗
- 怨媛李쏀
- 怨
- 怨
- 怨
- 怨듭
- 留臾멸린
- 遺理湲곕났
- 源李ш
- 諛李쎈
- 怨
- 源
-
- 源誘쇱
- 源
- 諛
-
-
-
- 蹂以
- 沅
- 以
- 以
- 以
- 源
- 沅諛곗＜
-
-
- 源誘쇱
- Hospital de Guipuzcoa San Sebastian Spain Gonzalo Vega - Hazas Porrua
- Eulji university hospital Yookyung Kim
- Gachon Medical School Gil Medical Center Seo Joon Beom
- Gospel Hospital, Kosin Medical College Hyunchul Kim
- Matsuyama Red Cross Hospital Shunya Sunami
- Seoul National University Hospital Seong Ho Park
- Seoul National University Hospital Choi Hyuck Jae
- Stedelijk OLV Ziekenhuis Mechelen, Belgium Ivan Pilate

대한흉부영상의학회 Korean Society of Thoracic Radiology

Archive of Old Cases

Case No : 133 Date 2000-05-13

Discussion

No. of Applicants : 50