|
Transserosal optical coherence tomography (OCT) with angiography modality (OCTA) provides real-time label-free visualization of the intestinal structure and blood vessels networks with a spatial resolution about 10-15 µm. This method is a perspective for intraoperative use in abdominal surgery, for example, for determining the depth of ischemic damage to the gut. The paper devoted to analysis the quality of OCT/OCTA data obtained from small intestine of 4 subjects - rat, rabbit, minipigs and humans. The subjects have different thickness of intestinal wall and blood circulation conditions. It was shown, that the intestine of small laboratory animals (rats and rabbits) is convenient for studying with OCT/OCTA: it can be easily stabilized by moving the intestine loop outside the body, which, together with a rigidly fixed probe, minimizes the number of possible motion artifacts. Therefore, OCT/OCTA criteria of structural changes in the intestinal wall and microcirculation disorders during ischemia, important for clinical applications, were established on these objects. Large animals (minipigs) and human proved to be a troublesome subjects for obtaining high-quality OCT/OCTA data: powerful peristaltic movements, pronounced pulse wave and the inability to take the object out of the body in order to exclude the influence of respiratory and other types of the body movements led to a sharp increase in the amount of OCT/OCTA images with artifacts (up to 39% in humans). However, in patients and minipigs the microstructure of intestinal layers was more informative than in small animals due to increased thickness. Therefore, it allowed visualize tissues in more detail: in particular, verify peritoneum edema and intramuscular fluid buildup. The study was performed under support of RFBR grant No.19-75-10096.
|
