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Bronchopleural-subarachnoid fistula manifesting as intracranial gas on CT scans.

The patient was a 65-year-old woman who had radiation treatment (6180 cGy) and surgical resection of a right-sided Pancoast tumor. The tumor resection was complicated by a leak of CSF from the dural sleeve of the right T2 nerve root. A tear in the dura was found and overlaid by two separate fat grafts obtained from the adipose tissue in the margins of the primary incision. A Valsalva maneuver done after the procedure indicated no evidence of residual CSF leak. The patient had an uneventful postoperative course and was discharged on the sixth postoperative day with no evidence of a CSF leak. A chest radiograph at that time showed a small postoperative pneumothorax at the apex of the right lung (Fig. 1A). Two months later the patient had dizziness, malaise, and confusion. A chest radiograph showed an enlarged right apical gas collection and no pleural fluid (Fig. 1B). A bronchopleural fistula was considered, but the changes in her mental status prompted a CT of the head to rule out metastatic disease. The lateral CT scan of the head (Fig. 1C) showed gas within the ventricular system, which was confirmed by axial images (Fig. 1D). Subarachnoid gas was also present. Later the same day, a CT scan of the chest showed the right apical gas collection and pleural fluid. Aspiration revealed clear yellow-tinged fluid that was consistent with CSF on laboratory evaluation. A small-caliber chest tube was positioned in the right apical gas collection for drainage and treatment of bronchopleural fistula. A follow-up CT scan of the head showed resolution of the ventricular and subarachnoid gas.