Low-dose indocyanine green fluorescence-navigated segmentectomy: prospective analysis of 20 cases and review of previous reports

Is the near‐infrared fluorescence imaging with intravenous indocyanine green method for identifying the intersegmental plane concordant with the modified inflation‐deflation method in lung segmentectomy?

“…Notwithstanding the evidence, the incidence of adverse events due to ICG has been reported to be 0.05% . Furthermore, anaphylaxis to ICG may be mediated by a dose‐dependent pseudo‐allergic mechanism, and the dose of ICG used for segmentectomy ranged from 0.25 to 5 mg/kg, with even a lower dose of 5 mg/bodyweight, and no complications attributed to ICG . The dose of ICG routinely used in our central segmentectomy was 2 mL (25 mg dissolved in 10 mL saline, equivalent to 5 mg/body), which had accumulated to more than 280 cases, and no ICG‐related complications had been found.…”

“…The technique for the formation of the intersegmental plane based on NIR fluorescence imaging with intravenous administration of ICG has recently advanced considerably due to its simplicity, rapidity, and less complicated restrictions, and its application has been reported in several studies . The mechanism is based on the fact that the intravenous ICG can rapidly combine with plasma, and in plasma the emission spectrum of ICG peaked at 780‐805nm fluorescence.…”

“…After an interval of approximately 10 to 15 minutes, an irregularly curved demarcation was identified naturally between the deflated preserving segments and the inflated target segment, which was no longer changing over time. Simultaneously, ICG at 2 mL (25 mg dissolved in 10 mL saline, equivalent to 5 mg/bodyweight), was rapidly injected into the peripheral vein, and the demarcation was also visualized using NIR fluorescence thoracoscopy, approximately 10–15 seconds later, the surrounding segments were stained, but not the targeted segment so that a distinct boundary between the two areas was clearly identified . In the study, we used the following NIR thoracoscopy system: PINPOINT Endoscopic Fluorescence Imaging System (Novadaq, Ontario, Canada), and this was used throughout the entire surgical procedure from start to finish.…”

“…Although the feasibility of thoracoscopic segmentectomy has been widely demonstrated, there is still controversy regarding technical issues, such as the identification of the intersegmental plane. Although many studies have reported several methods for identifying the intersegmental demarcation, their essence is two types aiming to generate a demarcation: inflation‐deflation line and dyeing the plane . The former representative method is modified inflation‐deflation, and this method is precise, simple, easy to operate, and does not require additional auxiliary materials, widely used as a standard technology in clinical practice.…”

“…However, it is not easy to visualize the demonstration of the intersegmental plane in pulmonary emphysema, and the inflated lung may obstruct the view of the target segment . The latter representative method is near‐infrared (NIR) fluorescence imaging with intravenous indocyanine green (ICG), which has been recently developed and several studies have reported the utility for the demonstration of the intersegmental plane . However, the concept of NIR fluorescence imaging with intravenous indocyanine green method for the demonstration of the intersegmental plane raises several controversial issues.…”