Caliber jump
In medicine, a sudden narrowing of vessels is referred to as a caliber jump . The term is often used in the context of vascular diagnostics in cardiology and pulmonology and is also used in relation to other hollow organs, among others, in urology (e.g. caliber jump of the urethra ), orthopedics (e.g. caliber jump of a tendon ) , gastroenterology (e.g. jump in caliber in the case of Hirschsprung's disease , jump in caliber of the intestine in mechanical ileus ) and in rheumatology (e.g. jump in caliber in rotator cuff ruptures ).
root cause
A caliber jump generally arises from the fact that the flow resistance is adjusted as a reaction to a pressure , but this is not reduced by a continuous pressure equalization but, on the contrary, by a very sudden one and this leads to the narrowing of the passage .
A jump in the caliber of the vascular lumen in pulmonary vessels, for example, as occurs in the Eisenmenger reaction , for example, occurs when central vessels are expanded due to increased lung pressure but are unable to contract. As a result, the vessel caliber (vessel width) does not decrease evenly in the direction of the periphery as usual, but rather decreases very sharply “in one go” and the flow rate suddenly narrows.
Examples
In addition to the already mentioned caliber jump in the context of the Eisenmenger reaction, z. B. also with cor pulmonale in an advanced stage in the chest x-ray enlarged central pulmonary arteries and a jump in caliber to the peripheral arteries .
In the presence of cirrhosis of the liver , the portal vein enlarges with a jump in caliber.
