Diabetic foot ulcer is the most devastating complication of diabetes that is still un-recognized. The treatment costs of these ulcers are very high to eventually save the leg/foot from amputation. To date, clinicians employ visual inspection of the wound site during its standard 4-week of healing process via monitoring of surface granulation. There is a need to develop on-site, low-cost imaging tools that can monitor the wound healing process periodically during the standard 4-week treatment process. A novel ultra-portable near-infrared optical scanner (NIROS) has been developed at the Optical Imaging Laboratory that can perform non-contact 2D area imaging of the wound site. Non-contact optical imaging studies were carried on diabetic subjects with foot ulcers (at Somesh Diabetic Foot Clinic, India) that were of healing and non-healing nature. A 710 nm LED source and a compact NIR sensitive camera were employed during non-contact imaging of the diabetic foot in order to obtain the near-infrared absorption images. From these preliminary studies it was observed that the non-healing wounds had a greater absorption contrast with respect to the normal site, unlike in the healing wounds. Demonstrating the ability of NIROS to differentiate healing vs. non-healing wounds in diabetic subjects can potentially impact early intervention in the treatment of diabetic foot ulcers.
Non-contact based near-infrared (NIR) optical imaging devices are developed for non-invasive imaging of deep tissues in various clinical applications. Most of these devices focus on obtaining the spatial information for anatomical co-registration of blood vessels as in sub-surface vein localization applications. In the current study, the anatomical co-registration of blood vessels based on spatio-temporal features was performed using NIR optical imaging without the use of external contrast agents. A 710 nm LED source and a compact CCD camera system were employed during simple cuff (0 to 60 mmHg) experiment in order to acquire the dynamic NIR data from the dorsum of a hand. The spatio-temporal features of dynamic NIR data were extracted from the cuff experimental study to localize vessel according to blood dynamics. The blood vessels shape is currently reconstructed from the dynamic data based on spatio-temporal features. Demonstrating the spatio-temporal feature of blood dynamic imaging using a portable non-contact NIR imaging device without external contrast agents is significant for applications such as peripheral vascular diseases.
Near-infrared (NIR) optical imaging modality is one of the widely used medical imaging techniques for breast cancer
imaging, functional brain mapping, and many other applications. However, conventional NIR imaging systems are
bulky and expensive, thereby limiting their accelerated clinical translation. Herein a new compact (6 × 7 × 12 cm3),
cost-effective, and wide-field NIR scanner has been developed towards contact as well as no-contact based real-time
imaging in both reflectance and transmission mode. The scanner mainly consists of an NIR source light (between 700-
900 nm), an NIR sensitive CCD camera, and a custom-developed image acquisition and processing software to image an
area of 12 cm2. Phantom experiments have been conducted to estimate the feasibility of diffuse optical imaging by using
Indian-Ink as absorption-based contrast agents. As a result, the developed NIR system measured the light intensity
change in absorption-contrasted target up to 4 cm depth under transillumination mode. Preliminary in-vivo studies
demonstrated the feasibility of real-time monitoring of blood flow changes. Currently, extensive in-vivo studies are
carried out using the ultra-portable NIR scanner in order to assess the potential of the imager towards breast imaging..
Cerebral palsy (CP) is a term that describes a group of motor impairment syndromes secondary to genetic and/or
acquired disorders of the developing brain. In the current study, NIRS and motion capture were used simultaneously to correlate the brain’s planning and execution activity during and with arm movement in healthy individual. The prefrontal region of the brain is non-invasively imaged using a custom built continuous-wave based near infrared spectroscopy (NIRS) system. The kinematics of the arm movement during the studies is recorded using an infrared based motion capture system, Qualisys. During the study, the subjects (over 18 years) performed 30 sec of arm movement followed by 30 sec rest for 5 times, both with their dominant and non-dominant arm. The optical signal acquired from NIRS system was processed to elucidate the activation and lateralization in the prefrontal region of participants. The preliminary results show difference, in terms of change in optical response, between task and rest in healthy adults. Currently simultaneous NIRS imaging and kinematics data are acquired in healthy individual and individual with CP in order to correlate brain activity to arm movement in real-time. The study has significant implication in elucidating the evolution in the functional activity of the brain as the physical movement of the arm evolves using NIRS. Hence the study has potential in augmenting the designing of training and hence rehabilitation regime for individuals with CP via kinematic monitoring and imaging brain activity.