The role of indocyanine green fluorescence for intersegmental plane identification during video-assisted thoracoscopic surgery segmentectomies

Abstract

Background: According to recent studies, thoracoscopic segmentectomy is an acceptable alternative to lobectomy for treating different lung diseases. This approach appears to have equivalent rates of postoperative morbidity with potentially similar long-term results even in selected lung cancer patients. At the same time, surgical success is highly dependent on intraoperative interpretation of segmental anatomy. We aimed to analyze our lung segmentectomy experience and identify the role of indocyanine green (ICG)-fluorescence for intersegmental plane detection.

Methods: A total of 86 consecutive patients who underwent 90 thoracoscopic segmentectomies with near-infrared-indocyanine green (NIR-ICG) method between September 2015 and December 2017 were investigated. According to the preoperative 3D lung hilar model, vascular and bronchial branches of the target segment were divided. ICG was thereafter injected into the central or peripheral vein. The boundary lines between the areas with and without fluorescence was marked on the visceral pleura by electrocautery.

Results: The fluorescence was detected immediately after bolus ICG injection in the central vein in all patients but had a time delay of 10-25 seconds in cases of peripheral vein administration. The median duration of intensive ICG staining was 90 seconds, regardless of the injection method. Well-defined fluorescence borders were observed in 86 of 90 (95.6%) segmentectomies due to technical reasons in three cases and severe emphysema in one. Chronic obstructive pulmonary disease (COPD) in other patients did not impair the boundary line identification, but reduced the duration of intensive ICG staining. No ICG-related complications were observed.

Conclusions: The ICG-fluorescence technology is safe and effective for verification of anatomic segment borders for video-assisted thoracoscopic surgery (VATS). The perfusion-based ICG fluorescence technique has advantages for thoracoscopic surgeries compared to other methods. Doubling the dose of ICG allows clear detection of the intersegmental plane, even in certain suboptimal conditions.

Keywords: Indocyanine green (ICG); fluorescence; intersegmental plane; near-infrared (NIR); thoracoscopic segmentectomy.

Conflict of interest statement

Conflicts of Interest: The authors have no conflicts of interest to declare.

Figures

Figure 1

Preoperative 3D right lung hilar model (planned S3 segmentectomy). S, segment.

Figure 2

Intraoperative view before (top picture) and after (bottom picture) interlobar LN dissection (planned right S2 segmentectomy). S, segment; LN, lymph node.

Figure 3

ICG fluorescence during right S3 segmentectomy in visible spectrum (on the left picture) and NIR spectrum (on the right picture). S3 appeared dark. S, segment; NIR, near-infrared; ICG, indocyanine green.

Figure 4

Right S2 segmentectomy—lung specimen (peripheral stumps of pulmonary arteries, vein, and bronchus are surrounded by stapling lines). S, segment.

Figure 5

Lobe-specific lymphadenectomy of station 7 (on the left picture) and stations 2–4 (on the right picture).