Dogra Photoacoustic and Ultrasound Imaging Laboratory
Our laboratory is mainly focused on Ultrasound and Photoacoustic imaging projects that will complement current diagnostic technologies to detect cancer. Photoacoustic imaging is an emerging technology which is a combination of laser and ultrasound to differentiate cancer from normal tissue in a non-invasive and non-ionizing procedure. We are the pioneers working with this emerging technology in a novel manner to build a low cost portable C-scan photoacoustic imaging systems based on patented design applications. We have investigated and validated this technology to detect cancer using several human ex-vivo specimens (prostate, thyroid and kidney) and the results have been presented in various scientific journals. We are currently investigating the development of contrast agents that will help detect cancers at an early stage by examining the molecular and cellular profiles of the target.
Our goal is to develop photoacoustic imaging devices for prostate, thyroid, breast and skin that will benefit the humanity for better lives. Using our novel patented approach to adapt this photoacoustic technology, we will design low cost imaging devices to help physicians evaluate cancer prognosis, response to drugs, target accurate biopsies and detection of cancer recurrence.
When a laser pulse of short duration (a few nanoseconds) interacts with an optical absorber inside the tissue, it results in localized heating of the tissue followed by rapid thermal expansion, generating thermo-elastic stress waves from the absorber. This effect is known as photoacoustic effect and the resulting stress (ultrasound) waves are referred to as photoacoustic waves. (Figure 1)
Advantages of Photoacoustic Imaging
- PA imaging is non-ionizing and non-invasive.
- PA signal strength depends on the optical absorption coefficient of absorber in the medium and the signal frequency depends on the size of the absorber and duration of the illuminating pulse.
- PA imaging provides functional information such as hemoglobin concentration, oxygen saturation and lipid content.
- It aids in detection of cancer along with disorders including but not limited to fibrosis, perfusion, edema, hypoxia and necrosis.
Current Research Projects
- The History of US: From Bats and Boats to the Bedside and Beyond: RSNA Centennial Article.Radiographics. 35, 960-70. (2015 May 14).
- Preliminary results of ex vivo multispectral photoacoustic imaging in the management of thyroid cancer.AJR Am J Roentgenol. 202, W552-8. (2014 Jun 01).
- Imaging of traumatic injuries to the scrotum and penis.AJR Am J Roentgenol. 202, W512-20. (2014 Jun 01).