Dual-Modality Intraoperative Cancer Navigation
A first-of-its-kind handheld probe that lets a surgeon confirm cancer while the patient is still on the table.
A surgeon removing a tumour has historically had to wait three to four days for histopathology to confirm whether the margin was clean. SAIGC-Torch collapses that wait to the length of the operation. It combines indocyanine green fluorescence with Technetium-99m gamma detection in a single completely handheld device: fluorescence to see the margin, gamma to find the sentinel node.
successful detection in oral, throat and breast cancer trials
- ICG fluorescence excitation
- 780 nm
- Technetium-99m gamma detection
- 140 keV
- Wait for validation (was 3-4)
- 0 days
- Histopathology correlation
- 100%
Summary
What the work set out to do, and the reasoning that shaped it.
SAIGC-Torch is a first-of-its-kind, completely handheld navigational probe designed to assist surgeons in the real-time identification of cancerous tissues during surgery. Developed indigenously, it provides a combined-modality approach by integrating fluorescence and gamma imaging for superior surgical validation.
The two modalities answer different questions. Indocyanine green fluorescence, excited at 780 nm, allows surgeons to visualise tumour margins with high sensitivity: where does the tumour end. Gamma imaging, detecting Technetium-99m at 140 keV, localises sentinel nodes and monitors metabolic tumour activity: where has it gone.
Every component: the shielding technology, the scintillators, and the AI-driven detection software: was developed at the Sri Sathya Sai Institute of Higher Learning.
Impact
What changed as a result.
In trials involving oral, throat and breast cancer, the device achieved 100% successful detection, correlating perfectly with gold-standard histopathology results.
Unlike bulky large field-of-view cameras, SAIGC-Torch is portable and provides live validation within the operating theatre: eliminating the three-to-four-day wait typical of traditional reports.
The device represents a fully indigenous capability: shielding, scintillators and detection software all developed in-house.
Figures
The work, drawn.
Purpose-built diagrams: each one carries an idea that prose alone would take a page to deliver.
Two channels, one probe
ICG fluorescence at 780 nm delineates the margin; ⁹⁹ᵐTc gamma at 140 keV finds the node. Neither modality alone is sufficient.
Handheld form factor
Completely handheld: the constraint that determines every other design decision in the instrument.
Intraoperative workflow
Live validation inside the theatre replaces the three-to-four-day histopathology wait with a decision made during the procedure.
Trial outcomes
Oral, throat and breast cancer trials: 100% successful detection, correlated against gold-standard histopathology.
Methods
How it was done.
Fluorescence channel
Indocyanine green (ICG) excited at 780 nm provides high-sensitivity visualisation of tumour margins in the surgical field.
Gamma channel
Technetium-99m detection at 140 keV localises sentinel nodes and monitors metabolic tumour activity, giving depth information that optical methods cannot reach.
Combined-modality validation
The two channels are complementary rather than redundant: fluorescence delineates the visible margin, gamma confirms nodal involvement. Agreement between them is what produces surgical confidence in real time.
Indigenous shielding and detection
Shielding technology, scintillators and AI-driven detection software were all developed at SSSIHL rather than sourced: a requirement for both cost control and design freedom.
Specifications
The numbers.
Development timeline
From simulation to the clinic.
Project sanctioned
DAE-BRNS awards ₹108 Lakhs for the design and development of a gamma-fluorescence dual imaging intraoperative probe. Dr. Ravi serves as Principal Investigator.
Dual-channel architecture
Optical excitation and emission path for ICG at 780 nm integrated alongside a gamma detection channel tuned to 140 keV, within a single handheld envelope.
Indigenous component development
Shielding technology, scintillators and AI-driven detection software developed in-house at SSSIHL.
Clinical validation
Trials in oral, throat and breast cancer. 100% successful detection, correlating with gold-standard histopathology.
Project completion
Six-year programme concludes with a portable probe delivering live validation inside the operating theatre.
Outcomes
- A first-of-its-kind completely handheld dual-modality navigational probe
- 100% successful detection in oral, throat and breast cancer trials
- Perfect correlation with gold-standard histopathology
- Elimination of the 3-4 day wait for traditional reports
- Fully indigenous shielding, scintillator and detection software stack
Collaborators & support
- Sri Sathya Sai Institute of Higher Learning
- DAE-BRNS (Board of Research in Nuclear Sciences)
Funded under
DAE-BRNS · INR 108 Lakhs
2017-2023 · Principal Investigator