Teaching Case

A 36-year-old male patient was brought to the casualty complaining of acute onset chest pain and dyspnea following a minor fall.

A chest radiograph (Fig. 1) was obtained which revealed a moderate sized left pleural effusion and left paramediastinal opacity.
Further, the patient was evaluated with CECT thorax (Figs. 2a, 2b, 2c, ), which showed a lobulated septate anterior mediastinal cystic lesion located in the left paramedian region with adjacent lung parenchymal changes and left pleural effusion.
Following the CT examination, the patient was taken to surgery and partial excision of the cystic lesion was done. Pathological examination confirmed the diagnosis of cavernous lymphangioma.

Background: Cysts account for approximately 20% of all mediastinal masses and occur in anterior, middle as well as in the posterior mediastinum. Those commonly encountered in the anterior mediastinum include pericardial cysts, thymic cysts, cystic teratoma, and lymphangioma [1].
Clinical perspective: Lymphangiomas represent less than 5% of these and occur in two forms. In infants, they present as cystic masses extending often from the neck into the mediastinum; whereas in adults, they are often confined to mediastinum which accounts for about 1% of mediastinal cystic lesions [1, 2].
Complications are unlikely in occurrences with lymphangiomas; infection, haemorrhage, rupture and compression of mediastinal structures owing to large dimensions, being those occasions which bring these otherwise asymptomatic lesions to light [1, 3].
Imaging Perspective: Radiography reveals lymphangiomas to be well defined rounded or lobular masses which on CT demonstrate homogenous fluid attenuation with imperceptible walls and thin septations. Owing to the pliable nature, the lymphangiomas often mold to or envelop or insinuate between adjacent structures rather than displacing them [1, 3, 4].