[Bronchogenic cysts and their atypical localizations. A case of pleuro-diaphragmatic cyst].

Bronchogenic cysts represent about 10 p. 100 of all surgical tumours of the mediastinum. They can never be diagnosed with absolute certainty prior to the operation, but when they arise in their typical sites, they can be suspected with a high probability. However, they can occur in very atypical sites, in which case the diagnosis remains very hypothetical until the operation. The authors report a case of a cyst which developed under the diaphragmatic pleura, in direct contact with the dome of the diaphragm and attached to the mediastinum by a fine vascular pedicle which inserted in the root of the triangular ligament.