High-Speed Integrated Endoscopic Photoacoustic and Ultrasound Imaging System

Abstract

Endoscopic integrated photoacoustic and ultrasound imaging has the potential for early detection of the cancer in the gastrointestinal tract. Currently, slow imaging speed is one of the limitations for clinical translation. Here, we developed a high speed integrated endoscopic PA and US imaging system, which is able to perform PA and US imaging simultaneously up to 50 frames per second. Using this system, the architectural morphology and vasculature of the rectum wall were visualized from a Sprague Dawley rat in-vivo.

Characterizing intestinal strictures of Crohn’s disease in vivo by endoscopic photoacoustic imaging

“…Recently, several PA endoscopy systems have been developed [21,22,[25][26][27][28][29]. However, all of these studies focused on imaging the hemoglobin content which is only correlated to the inflammation.…”

Minimally invasive photoacoustic imaging: Current status and future perspectives

“…Imaging in the gastrointestinal tract has attracted intensive research interest, mainly for the detection of early-stage tumour located in or close to the tract walls, such as oesophageal cancer [129,130] and colorectal cancer [57,98,131,132]. PAE holds great promise to visualise changes in vascular morphology and blood oxygenation and metabolism that are known to be associated with tumour development.…”

“…PAE holds great promise to visualise changes in vascular morphology and blood oxygenation and metabolism that are known to be associated with tumour development. In the past decade, a series of side-viewing PAE imaging systems have been developed and validated on small animal models, including rat rectum in vivo [131], melanoma tumour in rat colorectum in vivo [132], tumours of oesophagus and reflux esophagitis of a rabbit [129]. Visualisation of vascular morphology in the gastrointestinal tract was demonstrated with co-registered PA and US images.…”

Widefield illumination photoacoustic imaging of blood vessel phantom

“…Nondestructive tissue evaluation based on photoacoustic (PA) imaging has proved to be a crucial tool in biomedical applications for identifying specific features within biological tissues, such as blood vessels and nerve fibers, via detection of differences in light absorption . Alongside conventional optical imaging modalities such as diffuse optical tomography and optical coherence tomography, PA imaging, also known as optoacoustic imaging, can overcome the limitations of shallow imaging depth or optical diffusion in highly turbid media, as well as provide a solution to the problem of low image contrast because of speckle artifacts, which is associated with the abovementioned solely optical imaging modalities . The latter advantage is a result of the detection of mechanical changes or ultrasonic waves as pressure signals, which are produced by thermoelastic expansion in the target objects upon the absorption of short‐pulsed laser beams, dependent on the laser wavelength .…”

“…1,2 Alongside conventional optical imaging modalities such as diffuse optical tomography and optical coherence tomography, PA imaging, also known as optoacoustic imaging, can overcome the limitations of shallow imaging depth or optical diffusion in highly turbid media, as well as provide a solution to the problem of low image contrast because of speckle artifacts, which is associated with the abovementioned solely optical imaging modalities. 3,4 The latter advantage is a result of the detection of mechanical changes or ultrasonic waves as pressure signals, which are produced by thermoelastic expansion in the target objects upon the absorption of short-pulsed laser beams, dependent on the laser wavelength. 5,6 In this article, we present the demonstration of a simple and efficient PA imaging system, introducing widefield expanded-laser-beam illumination that fully covers the sample area of interest, in contrast to illumination based on point or focused sources.…”