Imaging of the Ovine Corpus Luteum Microcirculation with Contrast Ultrasound

• Published in: Ultrasound in medicine & biology Vol. 37; no. 1; pp. 59 - 68
• Main Authors: Sboros, Vassilis, Averkiou, M, Lampaskis, M, Thomas, D.H, Silva, N, Strouthos, C, Docherty, J, McNeilly, A.S
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 2011; Elsevier
• Subjects: Angiogenesis; Animals; Area Under Curve; Biological and medical sciences; Contrast imaging; Contrast media; Contrast Media - administration & dosage; Contrast Media - pharmacokinetics; Corpus luteum; Corpus Luteum - diagnostic imaging; Data processing; Dinoprost - pharmacology; Estrous Cycle; Estrus cycle; Female; Genital system. Mammary gland; Hemodynamics; Image processing; Image Processing, Computer-Assisted; Intravenous administration; Investigative techniques, diagnostic techniques (general aspects); Kinetics; Medical sciences; Microbubble; Microcirculation; Microvasculature; Perfusion; Phospholipids - administration & dosage; Phospholipids - pharmacokinetics; Probes; Prostaglandin F2 alpha; Radiology; Regression Analysis; Sheep ovary; Sheep, Domestic; SonoVue; Sulfur Hexafluoride - administration & dosage; Sulfur Hexafluoride - pharmacokinetics; Tracer kinetics; Ultrasonic investigative techniques; Ultrasonography; Ultrasound; Contrast imaging; SonoVue; Microbubble; Tracer kinetics; Ultrasound; Sheep ovary; Sonography; Microcirculation; Ovary; Vertebrata; Mammalia; Sulfur hexafluoride; Perfusion; Animal; Female genital system; Echography; Corpus luteum; Sheep; Artiodactyla; Hemodynamics; Ungulata; Contrast media
• ISSN: 0301-5629; 1879-291X
• DOI: 10.1016/j.ultrasmedbio.2010.10.013

Abstract Ultrasound contrast agents have been the subject of microvascular imaging research. The sheep corpus luteum (CL) is a microvascular tissue that provides a natural angiogenic and antiangiogenic process, which changes during the luteal phase of the estrous cycle of the ewe. It can also be controlled and monitored endocrinologically, providing a very attractive in vivo model for the study and development of microvascular measurement. The perfusion of the fully developed CL between days 8 and 12 of the estrous cycle was studied in six ewes. A Philips iU22 ultrasound scanner (Bothell, WA, USA) with the linear array probe L9-3 was used to capture contrast-enhanced images after an intravenous bolus injection of 2.4 mL SonoVue (Bracco S.P.A., Milan, Italy). Time-intensity curves of a region of interest inside the CL were formed from linearized image data. A lagged-normal model to simulate the compartmental kinetics of the microvascular flow was used to fit the data, and the wash-in time was measured. Good contrast enhancement was observed in the CLs of all animals and the wash-in time averaged at 5.5 s with 9% uncertainty. The regression coefficient was highly significant for all fits. These data correlated with stained endothelial area in the histology performed postmortem. Two ewes were injected with prostaglandin F2alpha to induce CL regression, which resulted in an increase of wash-in time after a few hours. The CL of the ewe is thus proposed as an ideal model for the study and development of microvascular measurements using contrast ultrasound. Our initial results demonstrate a highly reproducible model for the study of the microvascular hemodynamics in a range of tissues and organs. (E-mail: Vassilis.Sboros@ed.ac.uk )