PMC9748708_01
CT angiography of the abdominal aorta. (A) Coronal imaging revealed a low-density cystic mass with a Hounsfield units value of 30 on the left front of the T12-L2. The size of the cyst was determined to be ~3x4x6 cm. The lower part of the cyst is adjacent to the left renal artery and the medial part is adjacent to the abdominal aorta. (B) Upper cross-sectional imaging indicated that the cyst slightly compressed the abdominal aorta and originated from the left diaphragmatic crus, with the upper part located in the retrocrural space. (C) Middle cross-sectional imaging revealed that the lower part of the cyst extended into the retroperitoneal space. (D) Cross-sectional imaging below indicated that the lower edge of the mass was adjacent to the left renal artery.
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The size of the cyst was ~3x4x6 cm (Fig. 1A). The upper segment of the cyst was in the retrocrural space, whereas the lower segment was in the retroperitoneal space (Fig. 1B-D). The CT scanning parameters were as follows: Slice thickness, 5 mm; tube voltage, 120 kV; tube current, 200 mA.
Enhanced MRI images. (A) A cyst located in the retroperitoneal area originating from the left diaphragmatic crus, close to the spine and the right side of the abdominal aorta. (B) The fluid-fluid level was visible in the cyst. The cyst compressed the right side of the abdominal aorta was mildly compressed, with higher fluid signal values in the upper layer and lower signal values in the lower layer. Enhanced scan revealed that the cyst wall was smooth with no enhancement of cyst contents, but there was mild enhancement of the cyst wall.
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AG) revealed that the cyst originated from the left diaphragmatic crus, close to the spine and abdominal aorta, with a fluid-fluid level in the cyst (Fig. 2A). An enhanced scan indicated that the fluid signal in the upper layer of the cyst was higher compared with that in the lower layer (Fig. 2B). The contents of the cyst had no enhancement, whereas the cyst wall was smooth with mild enhancement (Fig. 2B).
H&E staining histopathological examination. (A and B) The cyst wall was covered with well-differentiated, pseudostratified and ciliated columnar epithelial cells. There were numerous cartilages and blood vessels in it and inflammatory cells had infiltrated. (A) magnification, x100 and scale bar, 400 microm. (B) Magnification, x400 of (A) and scale bar, 100 microm. (C and D) Cartilages and bronchial glands were found under the epithelium but no blood cells or calcium components were observed within the cyst. (C) Magnification, x100 and scale bar, 400 microm. (D) Magnification, x400 of (C) and scale bar, 100 microm.
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The results revealed that the cyst wall was covered with pseudostratified columnar epithelium (Fig. 3A and B). In addition, there were chondrocytes and bronchial glands but no blood cells or calcium components in the cyst, which was suggestive of a bronchogenic cyst (Fig. 3C and D).
No recurrence of the cyst can be observed with a T2-weighted imaging scanning on the sagittal were conducted during a 3-year follow-up period. (A) Pre-operation (fluid-fluid level indicated by arrow). (B) Immediately after, (C) 3 months, (D) 1 year and (E) 3 years after the operation.
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Of note, no recurrence of the cyst and any clinical symptom was observed at the immediate, 3 months, 1 year and 3 years postoperatively (Fig. 4A-E).