Indocyanine Green (ICG) fluorescence imaging allows surgeons to see what the naked eye cannot — lymph nodes glowing green, blood flow in real time, tumour margins illuminated, and vital structures highlighted to prevent injury. A single dye. Transformative surgical vision.
Silver Leaf Clinic — Center for Cancer, Robotic & Minimal Access Surgery.
ICG Fluorescence is used routinely by Dr. Vinod T. Gore at Silver Leaf Clinic and Sahyadri Manipal Hospitals — in open, laparoscopic, and robotic surgery — to enhance precision and improve patient outcomes.
Indocyanine Green (ICG) is an FDA-approved, near-infrared fluorescent dye that has revolutionised surgical precision across multiple specialities. When injected intravenously or directly into tissue, ICG distributes through the body's blood vessels and lymphatics — and when illuminated by a near-infrared (NIR) light source, it emits a bright green fluorescence visible only through a specialised NIR camera system.
The human eye cannot see near-infrared light — but the NIR camera converts this invisible signal into a vivid green image on a monitor, giving the surgeon a second layer of real-time information about tissue perfusion, lymphatic drainage, tumour margins, and vital structures that would otherwise be invisible or difficult to identify.
ICG itself is extremely safe — it is cleared entirely by the liver within 15–20 minutes, causes no radiation exposure, and has an excellent safety profile even in patients with liver disease. It has been used clinically since the 1950s for cardiac output measurement and is now the gold standard for intraoperative fluorescence imaging worldwide. Dr. Gore uses ICG routinely in cancer surgery — in open, laparoscopic, and robotic (da Vinci Firefly) platforms.
ICG has changed the way I operate. When I can see the parathyroid glands glowing during a thyroidectomy — even when I cannot identify them by colour or texture — I know they are preserved. When I see green perfusion across a colorectal anastomosis, I know it will heal. When the sentinel node lights up in my breast surgery patient, I know exactly where to go.
It is not a gadget — it is a precision tool. Surgery guided by ICG fluorescence reduces errors, preserves critical structures, and improves outcomes in measurable ways. I use it routinely at Silver Leaf Clinic and in the robotic theatre at Sahyadri Manipal Hospitals.
— Dr. Vinod T. Gore, MBBS MS FAIS FIAGES FARIS (Edin)ICG imaging is seamlessly integrated into the surgical workflow — the camera switches between white light (normal view) and NIR fluorescence mode in real time with a single button press.
ICG is injected intravenously (for perfusion, bile duct, SLN via blood) or intradermally / peritumorally (for lymphatic mapping). Dose: 0.1–0.5 mg/kg body weight.
ICG distributes through blood vessels, bile ducts, or lymphatics depending on injection site and route. Timing varies: IV perfusion — immediate; SLN — 5–30 minutes; bile duct — 15–30 minutes.
The NIR camera emits 750–800nm near-infrared light. ICG molecules absorb this light and emit fluorescence at 830nm. The camera captures this emission and displays it as a real-time bright green image on the monitor.
Surgeon switches between white light and NIR mode freely throughout the operation — using fluorescence to identify structures, confirm perfusion, or guide biopsy — then proceeds with precisely guided dissection.
Seven proven clinical applications — each delivering measurable improvement in surgical precision, patient safety, and oncological outcomes. Used routinely by Dr. Gore at Silver Leaf Clinic and Sahyadri Manipal Hospitals.
Enhancing Precision. Improving Outcomes.
ICG injected peritumorally or subdermally drains to the sentinel lymph node — which glows brightly under NIR light, allowing precise identification and targeted biopsy. Reduces unnecessary full axillary dissection, minimising lymphoedema risk. In endometrial cancer, ICG bilateral sentinel node mapping is now the standard technique.
Accurate sentinel node identification — spares unnecessary dissectionReal-time visualization of lymphatic channels and nodal basins — showing the exact drainage pathway from a tumour to its first-echelon nodes. Used in breast, gastric, colorectal, cervical, and thyroid cancers. Also valuable for assessing lymphatic disruption in lymphoedema management.
Real-time lymphatic channel visualisation — basin-specific nodal dissectionAfter bowel resection and before completing the anastomosis, ICG IV injection shows perfusion of the bowel ends in real time. Ischaemic (poorly perfused) bowel appears dark — the surgeon can then modify the anastomosis level to well-perfused tissue, significantly reducing anastomotic leak rates. One of the most impactful uses of ICG in colorectal, gastric, and oesophageal surgery.
Reduces anastomotic leak — real-time perfusion confirmation before closureICG given IV concentrates in bile (via liver) and outlines the bile duct and common bile duct in real time — dramatically reducing inadvertent bile duct injury during laparoscopic cholecystectomy. For ureter identification in colorectal, gynaecological, and retroperitoneal surgery, ICG injected into the renal pelvis illuminates the ureter, preventing inadvertent ureteral injury.
Prevents bile duct and ureteral injury — critical structures highlighted in real timeParathyroid glands autofluoresce under NIR light — naturally emitting green fluorescence without any ICG injection. This allows the surgeon to identify and preserve all four parathyroid glands during total thyroidectomy, preventing post-operative hypoparathyroidism and life-long calcium dependence. A major advance in thyroid surgery safety. Additionally, ICG perfusion after preserving parathyroid glands confirms their viability — if poorly perfused, they can be autotransplanted.
Parathyroid preservation in thyroidectomy — prevents permanent hypoparathyroidismHepatocellular carcinoma (HCC) and some liver metastases retain ICG due to impaired biliary excretion — causing them to glow brightly under NIR light. This delineates tumour margins precisely, enabling the surgeon to achieve true R0 resection even for lesions that are difficult to palpate or visualise under white light. Particularly valuable for laparoscopic and robotic liver surgery.
Precise tumour margin delineation — improved R0 resection rates in liver surgeryIn ovarian cancer surgery, tiny peritoneal metastases — invisible to the naked eye and undetectable by palpation — can be detected under NIR fluorescence after IV ICG. These occult deposits, if left behind, would leave residual disease and compromise the completeness of cytoreduction. ICG fluorescence allows the surgeon to detect and remove deposits that would otherwise be missed — improving cytoreductive completeness (CC0/CC1) and therefore survival outcomes.
Studies show ICG fluorescence detects peritoneal deposits not visible on white light in up to 29% of ovarian cancer patients — potentially converting an incomplete cytoreduction to a complete one, with direct impact on survival.
ICG (C₄₃H₄₇N₂NaO₆S₂) is a water-soluble tricarbocyanine dye originally developed in the 1950s for cardiac output measurement. Its near-infrared optical properties — absorbing at 750–800nm and emitting at 830nm — make it ideal for tissue imaging, since biological tissue has its lowest absorption and scattering in this wavelength range (the "optical window").
This means NIR light penetrates 5–10mm deeper into tissue than visible light — allowing ICG fluorescence to be detected through thin tissue layers, identifying structures beneath the surgical surface. The fluorescent signal is captured by a specialised NIR-equipped camera (integrated into the da Vinci robotic system as Firefly™, or as standalone NIR laparoscope and open systems).
ICG is entirely cleared by the liver via biliary excretion within 15–20 minutes of IV injection. It is not metabolised — it passes intact into bile and is excreted in faeces. This rapid clearance makes repeat dosing within a single operation possible, and eliminates concerns about drug accumulation or systemic toxicity.
The most powerful integration of ICG fluorescence is in robotic surgery — specifically through the da Vinci Firefly™ near-infrared imaging system, integrated directly into the robotic camera. With a single button press, the robotic console switches seamlessly between standard white light and NIR fluorescence mode, with no disruption to the surgical flow.
Dr. Gore uses ICG routinely in robotic cancer surgery at Sahyadri Manipal Hospitals — applying it across multiple surgical steps within a single operation, using ICG fluorescence at exactly the right moment for each critical decision.
Sentinel lymph node mapping with ICG — precise axillary and pelvic nodal identification without full dissection. Endometrial cancer bilateral SLN mapping.
Anastomotic perfusion assessment before stapling — confirms bowel ends are well vascularised, reducing anastomotic leak risk in low anterior resection and right hemicolectomy.
Parathyroid autofluorescence identification and ICG perfusion confirmation — preserves all four parathyroid glands, preventing permanent hypoparathyroidism after total thyroidectomy.
Peritoneal deposit detection in ovarian cancer, ureteral identification during radical hysterectomy, and lymphatic mapping in cervical cancer sentinel node procedures.
The Firefly™ system integrates a near-infrared light source directly into the da Vinci robotic camera — allowing seamless, real-time switching between white light and NIR fluorescence modes without removing the camera or disrupting the surgical field. The high-definition robotic optics provide superior fluorescence image quality compared to standard laparoscopic NIR systems.
ICG fluorescence delivers measurable, proven improvements across the four pillars of surgical quality — visualisation, precision, decision-making, and outcomes. These are not marginal gains — they translate directly into fewer complications, better cancer clearance, and faster recovery for patients.
— Silver Leaf Clinic · Center for Cancer, Robotic & Minimal Access Surgery · Expertise | Precision | Compassion | Better Surgery. Better Life.
Live fluorescence imaging during surgery — not pre-operative planning or post-operative review. The surgeon sees and responds in real time.
Structures identified with certainty. Margins confirmed. Perfusion assured. The surgeon operates with information that was previously unavailable.
Is this anastomosis safe to close? Is that tissue the parathyroid? Is there residual tumour here? ICG answers these questions objectively.
Fewer anastomotic leaks. Preserved parathyroids. Complete tumour resection. Better sentinel node accuracy. Real benefits, measurable in clinical trials.
ICG fluorescence adds a layer of precision to every cancer operation where it is applied — without adding complexity, risk, or significant time to the procedure.
Fluorescence is visualised live during surgery — not from pre-operative imaging or pre-planned maps. The surgeon responds to what is seen, exactly when it matters.
Multiple ICG injections can be given in a single operation — for different purposes at different stages. No cumulative limit within a procedure.
Unlike radioactive tracers used in traditional sentinel node procedures, ICG is a purely optical dye — no radiation to patient, surgeon, or theatre staff.
ICG is cleared from the bloodstream in 15–20 minutes via biliary excretion. Safe for repeat dosing. No accumulation or delayed toxicity.
Used in open, laparoscopic, and robotic surgery. The da Vinci Firefly system provides the best image quality — but NIR laparoscopes are also effective.
Fluorescence signal is objective — not dependent on surgeon experience or tactile feel. Parathyroid glands glow or they don't. Anastomotic blood flow is present or absent.
Rare allergic reactions (~1 in 42,000 cases). No nephrotoxicity, no cardiotoxicity. Safe in liver disease (excretion is hepatic — a diagnostic advantage). No contraindication in pregnancy for urgent cases.
ICG SLN in breast cancer and endometrial cancer — randomised controlled trial evidence. ICG anastomotic perfusion — prospective multicentre data. Parathyroid autofluorescence — growing evidence base.
ICG has an outstanding safety record established over 60+ years of clinical use. It is one of the safest diagnostic agents used in medicine — with an anaphylaxis rate of approximately 1 in 42,000 doses, which is significantly lower than most iodinated contrast agents used in CT and angiography.
Being a purely optical dye with no metabolic activity, ICG causes no organ toxicity, no nephrotoxicity, and no bone marrow suppression. Its rapid clearance via biliary excretion means it does not accumulate even with repeat doses during a single procedure.
Anaphylaxis rate: ~1 in 42,000 doses. Much lower than iodinated contrast agents. Adrenaline and resuscitation equipment available in theatre as standard.
No nephrotoxicity, hepatotoxicity, or cardiotoxicity at surgical doses. Safe in patients with renal impairment (biliary excretion only). Caution in severe liver failure (reduced clearance).
Entirely optical — no radioactivity, no radiation to patient or surgeon. Can be used in young patients, fertile women, and pregnant patients (for urgent indications) without radiation concerns.
In clinical practice, ICG is used routinely without pre-medication in the vast majority of patients. Allergy screening with a simple question about iodine or seafood allergy is standard. The overwhelming safety record makes ICG one of the most confidently used intraoperative agents in modern surgery.
Book a consultation with Dr. Gore to discuss how ICG fluorescence guided surgery can improve outcomes for your cancer operation — sentinel node mapping, parathyroid preservation, anastomotic safety, or peritoneal deposit detection.