# Seeing Blood Flow Deep Inside Tissue Without Touching It > This patent describes a way to create 3D images of blood flow up to 1.5 cm deep inside body tissue using near-infrared light, all without any physical contact with the skin. - **Patent:** US 9861319 - **Original title:** Noncontact three-dimensional diffuse optical imaging of deep tissue blood flow distribution - **Owner:** University of Kentucky Research Foundation - **Granted:** 2018 - **Status:** Active - **Times cited:** 5 - **Field:** medical_devices, biotech, software, consumer_electronics ## What it does This patent details an optical method for creating three-dimensional (3D) images of blood flow in deep tissue, specifically up to about 1.5 cm, without needing to touch the tissue (Claim 1). It works by projecting near-infrared light from long-coherence laser sources onto the tissue surface through optical lenses. A detector array then captures the diffused near-infrared light reflected back, also through lenses (Claim 1). The collected data is then processed, often using a finite-element-method (FEM), to reconstruct a 3D image of the blood flow distribution (Claim 6). For example, a surgeon could use this system to check the blood supply in a delicate skin graft during surgery without disturbing the healing tissue. ## What it does NOT cover - Does not cover imaging methods that require physical contact between the imaging probe or detector and the tissue (Claim 1). - Does not cover imaging deeper than approximately 1.5 cm into the tissue (Claim 1). - Does not cover imaging techniques that use light outside the near-infrared spectrum (Claim 1). - Does not cover two-dimensional (2D) imaging; it specifically focuses on three-dimensional (3D) image reconstruction (Claim 1). - Does not cover methods that do not use optical lenses for both applying and detecting the light (Claim 1). ## The clever bit The novelty lies in combining non-contact near-infrared light application and detection with advanced 3D image reconstruction techniques, such as the finite-element-method, to accurately map deep tissue blood flow in tissues with arbitrary shapes. This allows for safe, detailed analysis of vulnerable or sensitive tissues. ## Real-world examples 1. Monitoring blood flow in tissue flaps during reconstructive surgery 2. Assessing healing and circulation in burn wounds without direct contact 3. Evaluating blood supply in diabetic foot ulcers 4. Observing tissue perfusion during organ transplantation procedures 5. Research tools for studying microcirculation in biological tissues ## Why it matters This technology is important because it allows medical professionals to assess blood flow in sensitive, vulnerable, or damaged tissues without physical contact. This non-contact approach reduces the risk of infection, further injury, or disruption to healing processes. It is particularly valuable for monitoring open wounds, surgical sites, or delicate tissue grafts where traditional contact-based methods would be problematic. ## Frequently asked questions ### What does Seeing Blood Flow Deep Inside Tissue Without Touching It cover? This patent describes a way to create 3D images of blood flow up to 1.5 cm deep inside body tissue using near-infrared light, all without any physical contact with the skin. ### Who owns patent US 9861319? University of Kentucky Research Foundation owns this patent, granted in 2018. ### When does this patent expire? This patent is expected to expire on March 23, 2036, when the invention enters the public domain. ### What is patent US 9861319 cited by? This patent has been cited by 5 later patents that build on its ideas. ### What problem does this patent solve? This technology is important because it allows medical professionals to assess blood flow in sensitive, vulnerable, or damaged tissues without physical contact. This non-contact approach reduces the risk of infection, further injury, or disruption to healing processes. It is particularly valuable for monitoring open wounds, surgical sites, or delicate tissue grafts where traditional contact-based methods would be problematic. ### What does this patent NOT cover? Does not cover imaging methods that require physical contact between the imaging probe or detector and the tissue (Claim 1). **Full plain-English explainer:** https://patentbrief.org/patent/us/9861319/noncontact-three-dimensional-diffuse-optical-imaging-of-deep-tissue-blood-flow-d **Original patent:** https://patents.google.com/patent/US9861319 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How to Take 3D Pictures Inside Human Tissue Using Near-Infrared Light](https://patentbrief.org/patent/us/RE38800/digital-video-recorder-dvr) — A system that uses flexible fiber optic cables to map the inside of complex body parts by shining light through them and measuring how it scatters. - [How a Wearable Device Measures Heart Rate and Blood Flow with Lasers](https://patentbrief.org/patent/us/12733827/optical-sensor-module) — This patent describes a wearable device that uses a single laser and two different optical sensors—an image sensor and a photodiode—to measure both blood flow patterns (SPG) and blood volume changes (PPG) from biological tissue. - [Real-Time Brain Blood Flow Monitoring to Prevent Dizziness and Falls](https://patentbrief.org/patent/us/12733882/methods-and-devices-to-detect-poor-cerebral-blood-flow-in-real-time-to-prevent) — This patent describes methods and devices for constantly checking blood flow to the brain to help stop people from getting dizzy, fainting, or falling. - [How Radio Waves Measure Heart Movement and Fluid in the Chest](https://patentbrief.org/patent/us/12733904/methods-and-systems-for-determining-fluid-content-of-tissue) — This patent describes a diagnostic system that uses multiple radio frequency antennas placed on the chest to send waves towards the heart, then analyzes the scattered signals to measure the heart's movement in detail. - [How to Adjust Specific Parts of an Ultrasound Image](https://patentbrief.org/patent/us/12733899/non-uniform-ultrasound-image-modification-of-targeted-sub-regions) — This patent describes a system that lets doctors brighten or change specific small areas within an ultrasound scan independently, without affecting the rest of the image.