Illuminating Surgery’s Brilliant New Frontier

The OnLume Imaging System Illuminates Critical Anatomy in Real-Time During Surgery to Improve Surgical Precision.

The fluorescence image quality generated by the OnLume Imaging System is grounded by a robust and growing body of science that has informed rigorous research and development; these advancements have the end goals of improved patient outcomes, increased procedural efficiency, and fewer surgical complications. 

Let’s explore the basics of the scientific concepts and technologies that are the core of OnLume’s advancements.  

Fluorescence is the emission of light by a molecule after being stimulated by incoming light. When a light source of a particular wavelength is shined onto a molecule, electrons may be excited to a temporary, higher energy state. As an electron returns to its original state very quickly (less than a nanosecond!), it gives off light of a longer wavelength. Fluorescence imaging for medical applications consists of “exciting” a fluorescent drug with light and then detecting the resulting emitted light in order to determine where the drug has gone within the body. These fluorescent drugs are highly versatile and can be used to target and image cancer cells, nerve fibers, or blood flow in real-time during surgical procedures.

What is fluorescence-guided surgery (FGS)? How does OnLume advance FGS? 

Fluorescence-guided surgery is a medical imaging technique that uses fluorescent drugs to help surgeons identify critical anatomy and assess function during surgical procedures, allowing a surgeon to see what would otherwise be invisible to the naked eye. It can also allow improved visualization of structures that are under the surface of a patient’s skin or surgical site.

The OnLume Imaging System’s low latency in the displayed hybrid white light/fluorescence video allows surgeons to directly manipulate the surgical field while viewing the fluorescence, enabling true “real time” procedural visualization.

Another benefit of fluorescence-guided surgery is the lack of ionizing radiation exposure to the patient or medical team while providing contemporaneous feedback, unlike modalities like intra-operative x-ray angiography. OnLume FGS is complementary to preoperative imaging techniques such as MRI, PET, and CT.

When the fluorescent drug is introduced to the body, it binds preferentially to specific proteins, cells, or structures. For this reason, surgery enhanced with fluorescence guidance offers surgeons more information than visual inspection or tactile feedback alone, enhancing their ability to truly assess tissue type and function. They can use this information to monitor blood flow and perfusion, prevent removal of healthy tissue, and optimize surgical outcomes. 

Cancer surgery applications of FGS are incredibly promising, and OnLume is working to further develop this clinical innovation through collaboration with novel targeted agents.  Tumor-specific drugs that deliver fluorescent dyes to cancer cells may help surgeons identify residual diseased tissue that could regrow or metastasize, preventing additional procedures or therapies.

OnLume has received US FDA 510(k) clearance for fluorescence imaging of blood flow and tissue perfusion before, during, and after vascular, gastrointestinal, organ transplant, plastic, reconstructive, and micro surgeries. The primary fluorescent agent used for these procedures is indocyanine green (ICG).

How will adoption of FGS affect surgeons, healthcare systems, and patients?

There is a dramatic opportunity for FGS to improve surgical outcomes in challenging procedures where compromised visibility or tissue delineation leads to lack of clinical certainty.

Examples of the indications where FGS could enhance surgical outcomes include:

Vascular and Reconstructive Surgery

  • 15 to 25% of cases require revision surgeries due to the inability to affirm proper perfusion while in the operating room1

Head and Neck Surgery

  • Up to 25% of cases result in surgical nerve damage2

Cancer Surgery

  • 23-38% recurrence in breast cancer due to residual cancer at margins3

Through enhanced real-time imaging of anatomic structures, OnLume provides surgeons with the information needed to make critical intra-operative decisions that lead to improved surgical outcome.

Leveraging advances in medical physics, engineering, and imaging with precisely engineered technology, real-time visualization, best-in-class ergonomics and performance, the OnLume Imaging System shines a powerful light leading to a future of more precise surgical procedures.

We have demonstrated that ICG fluorescence imaging enhances plastic surgeons’ assessment of supermicrosurgical anastomoses and provide real-time feedback to surgeons.4


  1. Robertson et al, (2017) Breast Cancer. 10.2147/BCTT.S81712.
  2. Antoniadis et al, (2014) Dtsch Arztebl Int. 10.3238/arztebl.2014.0273.
  3. Tringale et al, (2018) WIREs Sys Bio and Med. 10.1002/wsbm.1412.
  4. Albano et al, (Sept. 2020) The Addition of Fluorescence to the University of Wisconsin “Blue-Blood” Chicken Thigh Model Significantly Enhances Its Effectiveness As a Supermicrosurgery Training Tool. PRS GO.