TY - JOUR

T1 - Super-Resolution Ultrasound Imaging Provides Quantification of the Renal Cortical and Medullary Vasculature in Obese Zucker Rats

T2 - A Pilot Study

AU - Søgaard, Stinne Byrholdt

AU - Andersen, Sofie Bech

AU - Taghavi, Iman

AU - Hoyos, Carlos Armando Villagómez

AU - Christoffersen, Christina

AU - Hansen, Kristoffer Lindskov

AU - Jensen, Jørgen Arendt

AU - Nielsen, Michael Bachmann

AU - Sørensen, Charlotte Mehlin

N1 - Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

PY - 2022/7

Y1 - 2022/7

N2 - Obesity is a risk factor of chronic kidney disease (CKD), leading to alterations in the renal vascular structure. This study tested if renal vascular density and tortuosity was quantifiable in vivo in obese rats using microbubble-based super-resolution ultrasound imaging. The kidneys of two 11-week-old and two 20-week-old male obese Zucker rats were compared with age-matched male lean Zucker rats. The super-resolution ultrasound images were manually divided into inner me-dulla, outer medulla, and cortex, and each area was subdivided into arteries and veins. We quanti-fied vascular density and tortuosity, number of detected microbubbles, and generated tracks. For comparison, we assessed glomerular filtration rate, albumin/creatinine ratio, and renal histology to evaluate CKD. The number of detected microbubbles and generated tracks varied between animals and significantly affected quantification of vessel density. In areas with a comparable number of tracks, density increased in the obese animals, concomitant with a decrease in glomerular filtration rate and an increase in albumin/creatinine ratio, but without any pathology in the histological stain-ing. The results indicate that super-resolution ultrasound imaging can be used to quantify structural alterations in the renal vasculature. Techniques to generate more comparable number of microbub-ble tracks and confirmation of the findings in larger-scale studies are needed.

AB - Obesity is a risk factor of chronic kidney disease (CKD), leading to alterations in the renal vascular structure. This study tested if renal vascular density and tortuosity was quantifiable in vivo in obese rats using microbubble-based super-resolution ultrasound imaging. The kidneys of two 11-week-old and two 20-week-old male obese Zucker rats were compared with age-matched male lean Zucker rats. The super-resolution ultrasound images were manually divided into inner me-dulla, outer medulla, and cortex, and each area was subdivided into arteries and veins. We quanti-fied vascular density and tortuosity, number of detected microbubbles, and generated tracks. For comparison, we assessed glomerular filtration rate, albumin/creatinine ratio, and renal histology to evaluate CKD. The number of detected microbubbles and generated tracks varied between animals and significantly affected quantification of vessel density. In areas with a comparable number of tracks, density increased in the obese animals, concomitant with a decrease in glomerular filtration rate and an increase in albumin/creatinine ratio, but without any pathology in the histological stain-ing. The results indicate that super-resolution ultrasound imaging can be used to quantify structural alterations in the renal vasculature. Techniques to generate more comparable number of microbub-ble tracks and confirmation of the findings in larger-scale studies are needed.

KW - chronic kidney disease

KW - image analysis

KW - metabolic syndrome

KW - nephropathy

KW - obesity

KW - ultrasound localization microscopy

U2 - 10.3390/diagnostics12071626

DO - 10.3390/diagnostics12071626

M3 - Journal article

C2 - 35885531

AN - SCOPUS:85133719218

VL - 12

JO - Diagnostics

JF - Diagnostics

SN - 2075-4418

IS - 7

M1 - 1626

ER -