A safe method for marking small pulmonary nodules with crystal violet.

INTRODUCTION

The number of cases of wedge resection of small-sized pulmonary nodules performed under video-assisted thoracoscopic surgery (VATS) is increasing. Computed tomography (CT)-guided marking with hook wires has been used to locate the nodules that are not identifiable under VATS. However, this method is invasive and is associated with a risk of complications.

METHODS

We evaluated the usefulness of marking the pleural surface above the nodule using crystal violet for 22 small-sized pulmonary nodules. Following the collapse of the lung, a long stick with a cotton tip dipped in crystal violet was inserted from the thoracic port or a small thoracotomy, and was placed against the inside of the chest wall right above the nodule with reference to the preoperative CT image. The lung was then expanded, and the crystal violet-infiltrated tip stained the visceral pleura. Regardless of the marking point, wedge resection of the lung was performed. To evaluate the accuracy of the marking, we measured the distance from the center of the marking to the point on the visceral pleural nearest to the nodule (DMN) in the resected lung specimen.

RESULTS

This marking method caused no morbidity during or after the operation. The DMN ranged between 0 and 50 mm (mean ± SD 18.2 ± 12.6 mm). In 18 of 22 cases (81.8%), the DMN was 20 mm or less.

CONCLUSIONS

The intraoperative marking method using crystal violet was performed with reasonable accuracy. It also caused no morbidity. It was easy and non-invasive. This method can be used in the cases in which CT-guided percutaneous marking is not feasible due to the nodule's location.