Authors: Matthew D. Burstein, MD, PhD & Chibueze A. Nwaiwu, MD
Activ Surgical, Inc. received FDA approval for the ActivSight Intraoperative Imaging Module on April 8, 2021 (K203550).
The ActivSight Intraoperative Imaging Module installs between a standard laparoscope and white light camera system, with a separate proprietary “Light Engine” custom light source that combines white light with one or more coherent laser wavelengths. The system is placed along current commercial systems and delivers real-time tissue perfusion and blood flow information intraoperatively via the simultaneous imaging of light in the infrared spectrum. This allows for both conventional ICG based perfusion imaging and the novel addition of overlays built from laser speckle contrast imaging (LSCI), presenting dye-free, intraoperative visualization of critical hidden, sub-surface structures in real-time. Blood flow is represented in the form of a perfusion map using the colors in the visible light spectrum, with warmer colors indicating relatively higher blood flow than the area represented by cooler colors, which corresponds to relatively low flow and perfusion. If no flow is present, no false color is depicted on the image.
Safety and performance have been evaluated and verified in accordance with modern IEC 60601 standards (technical standards for medical electrical equipment including lasers).
An animal study was completed, comparatively visualizing perfusion in specific structures with both ActivSight Perfusion (laser speckle) and ActivSight ICG modes against the predicate’s ICG mode.
The FDA determined this device to be substantially equivalent to a predicate devices, the Stryker Infrared Fluorescence (IRF) Imaging System (K142310). The main differences between the two devices are ActivSight’s capability to visualize blood flow and perfusion through laser speckle imaging, and the exclusion of standard laparoscopic equipment including a white light source. Another predicate device Perimed PeriCam PSI (K120884) was capable of laser speckle imaging as well.
The ActivSight Intraoperative Imaging Module is FDA approved indications for real-time endoscopic fluorescence and near infrared imaging to assess vessels, blood flow, and related tissue perfusion during minimally invasive surgery. It is also approved for real-time endoscopic fluorescence and near infrared imaging of the major bile ducts (cystic duct, common bile duct, or common hepatic duct) during minimally invasive surgery.
Fluorescence imaging of biliary ducts with ActivSight is intended for use with standard of care white light and, when indicated, intraoperative cholangiography. The device is not intended for stand-alone use for biliary duct visualization.
Figure 1. Incomplete Sleeve Gastrectomy imaged with ActivSight during staple firings.
A. Ongoing sleeve gastrectomy shown in white light image (WLI) with the partially resected stomach specimen on the right (orange arrow). The current level of resection is denoted by a white line. B. Perfusion assessment of the same anatomy using ActivSight Perfusion Overlay mode showing high perfusion signals over the perfused sleeve and absence of blood flow on the partially resected stomach distal to the white line. The color bar on the right mid-portion of the image shows that warmer colors (yellow, orange, red) over a target anatomic site indicate areas of higher perfusion whereas cooler colors (blue) demonstrate areas of lower perfusion. Lack of color signal demonstrates lack of perfusion to the site. C. Assessment of the same anatomy using ActivSight Perfusion Contrast mode which displays the perfusion signals without showing the white light image of the underlying anatomy.
Perfusion assessment of the same anatomy was also performed using three ActivSight ICG modes: ICG Overlay mode (D) which shows the ICG signal over the WLI of the anatomy, ICG Grayscale mode (E) which portrays the ICG signal with the underlying anatomy in gray, and ICG Contrast mode (F) which shows the ICG signal over a dark background. These ICG images demonstrate concordance with the assessment performed using the ActivSight Perfusion modes.
Figure 2. Ileocolic anastomosis during a partial colectomy imaged with ActivSight.
A. Assessment of an ileocolic anastomosis in white light image (WLI), during a partial colectomy; ileum and small bowel mesentery on left (white arrow), colon and colonic mesentery on right (blue arrow). The anastomosis is suspended in the abdominal cavity with the ends of the attached suture (yellow arrow) pulled anteriorly. B. Perfusion to the ileocolic anastomosis is assessed using ActivSight Perfusion Overlay mode. Perfusion signals are noted over the anastomosis, proximally and distally. C. In ActivSight Perfusion Contrast mode which presents the perfusion signal only, without the white light image of the underlying anatomy, perfusion signals in warmer colors (red, orange, yellow) are noted.
Perfusion of the ileocolic anastomosis was also assessed using three ActivSight ICG modes: ICG Overlay mode (D), ICG Grayscale mode (E), and ICG Contrast mode (F). Again, these ICG images demonstrate concordance with the assessment performed using the ActivSight Perfusion modes.