Combined superior vena cavography and azygography in patients with suspected lung carcinoma.

Abstract

Intraosseous costal or spinous process azygography has occasionally been used for visualization of the thoracic venous system in the preoperative assessment of carcinoma of the lung (2, 7). Obstruction of the superior vena cava or extrinsic compression or invasion of its lumen is a relatively frequent finding in the natural history of pulmonary carcinoma, especially when the lesion originates in the right lung (3). In 85 per cent of 33 cases coming to autopsy in one series, cancer was the etio-logic agent producing superior vena caval obstruction (1). To our knowledge, the combined use of superior vena cavography and azygography as part of the preoperative assessment of pulmonary carcinoma has not been previously reported. Our experience with 63 consecutive patients who have been evaluated for suspected primary lung carcinoma by the use of superior vena cavography and azygography forms the basis of this report. The roentgenographic patterns of abnormality are evaluated and presented. The importance of proper technic is discussed. Assessment of each study separately and in combination is made to determine its value in defining resectability. Materials and Technic Sixty-three patients with suspected primary pulmonary cancer were evaluated by a diagnostic work-up which included pos-tero-anterior and lateral chest roentgenograms, transtracheal bronchography (6), azygography and superior vena cavography, scalene node biopsy, bronchoscopy, sputum cytology, and pulmonary function studies. The clinical records of each patient were reviewed, and the significance of the findings from azygography and superior vena cavography was correlated with the operative and pathological findings. Azygography and superior vena cavography were performed at the same time in all cases. Each patient was premedicated with 50 mg meperidine (Demerol), 100 mg secobarbital (Seconal), and 25 mg Phener-gan thirty minutes before the start of the procedure. A rapid-sequence film-changer should be used for both azygography and superior vena cavography if really meaningful results are to be obtained. False-negative examinations are greatly minimized (Fig.1). False-positive examinations due to spurious physiologic obstruction from the Valsalva maneuver or tightening of neck and shoulder musculature are eliminated by using serial exposures and by cautioning the patient to remain relaxed and to continue breathing normally throughout the injection and exposure times (Fig. 2, A and B). The equipment for superior vena cavography includes two 30 cc syringes, each containing 25 cc of 50 per cent Hypaque and No. 16 gauge needles with plastic connecting tubing. The basilic veins in both antecubital fossae are injected simultaneously by hand to give complete visualization of the innominate veins as well as of the superior vena cava. The total injection time is between two and three seconds.