The purpose of this study was to establish a new CT scan method to show signs of air leakage and to detect the point of the lung leak in patients with spontaneous pneumothorax by using saline solution and phonation.
Eleven patients with spontaneous pneumothorax who had a chest tube placed and underwent an operation because of continuing air leakage were studied. After a plain chest CT scan was performed, 0.9% saline was injected into the affected pleural cavity. A CT scan was acquired again while the patient vocalized continuously. The CT images were evaluated by two thoracic surgeons. All patients underwent video-assisted thoracoscopic surgery to confirm their points of leakage and were treated for spontaneous pneumothorax.
Bubble shadows were seen in nine of 11 cases. In seven of those nine cases, multiple bubbles formed foam or wave shadows. These cases had a small pleural fistula. In the other two cases with a large fistula, air-fluid level in bulla and ground-glass attenuation areas were seen in the pulmonary parenchyma. In all 11 cases, some air-leakage signs were seen on CT scan, and a culprit lesion was presumed to exist by analyzing CT imaging findings and confirming with a surgical air-leak test.
With a saline injection and vocalization, CT scan could demonstrate air-leak signs in patients with spontaneous pneumothorax. This method does not require contrast medium, special instruments, or high skill and, thus, is a novel and useful examination to detect the culprit lesion in pneumothorax.