Synapse 3D With Intravascular Indocyanine Green Fluorescence Mapping for Targeted Pulmonary Segmental Resection Trial: A Phase I Safety and Feasibility Trial

Lungs are made up of individual lobes. When a lung cancer tumour is found in one of these lobes, the surgeon often performs a Lobectomy. A Lobectomy is the surgery most commonly done to treat early-stage lung cancer and requires removal of an entire lobe of the lung, which removes a large amount of lung tissue

For patients with small tumours saving as much healthy lung tissue as possible is important. Each lobe of the lung has smaller sections called segments. When a lung cancer is in one of these segments, it is possible to remove that segment, without removing the entire lobe. This surgery is called a Segmentectomy. Compared to a lobectomy, a segmentectomy saves a larger amount of healthy lung tissue. Research shows that a segmentectomy can result in less blood loss, shorter operation time, less days of having a chest tube, and a shorter hospital stay, compared to a lobectomy.

With the advances in screening technology for lung cancer tumours, an increasing amount of very small lung cancer tumours are being found, and the demand for segmentectomy is increasing. A segmentectomy is a hard surgery to perform robotically because it is difficult to view the tissue lines that separate each segment within the lobe. As a result, it is difficult for the surgeon to see exactly which pieces of tissue should be removed in order to safely complete the segmentectomy. Because of these challenges, many patients having robotic surgery will have a lobectomy, even if a full lobectomy is not needed.

In response to these challenges, our surgical group has developed the technique of using Near-Infrared Fluorescence (NIF) mapping with intravascular indocyanine green (ICG) dye injection. With the aid of an infrared camera the surgeon is able to see the segment within a lobe of lung after injection of the ICG dye, allowing for a more accurate segmentectomy. We recently reported a 60% success rate of segmental resections with the use of ICG and NIF-guided surgical resection. However, a limitation to this technique is that the segmental anatomy can only be seen during the operation and only after cutting the blood vessels.

The introduction of 3D reconstruction and virtual modeling provides a new way to locate lesions accurately within a segment and plan the appropriate operation before the actual surgery occurs. Synapse 3D (Mississauga, Canada) is a 3D modelling technology that is capable of producing a detailed 3D virtual model of a patient's lung based on Computed Tomography (CT) scans. It has been shown to be safe and feasible in performing segmental pulmonary resections on a robotic platform. In this study, we propose a new operation that uses 3D anatomical planning before the surgery (Synapse 3D) and real-time NIF-mapping at the time of surgery using ICG dye, which we believe will greatly increase the likelihood of a successful segmentectomy. If this new operation is successful, it will help patients save more of their healthy lung tissue when they are undergoing surgery for lung cancer.