Can testicular artery Doppler velocimetry values change according to the measured region in dogs?

Abstract

Contents Testicular tissue maintenance is performed by the testicular artery, and the hemodynamics of this artery can be evaluated using Doppler ultrasonography. The aim of this study was to characterize the peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI) and resistivity index (RI) of five regions of the testicular artery in dogs, including two proposed regions and three that have been previously described. Twenty‐two dogs were used, and the PSV, EDV, PI and RI of the testicular artery were measured in five regions: proximal, medial and distal supratesticular; marginal; and intratesticular. The median values for PSV (cm/s), EDV (cm/s), PI and RI in the five regions were as follows: proximal supratesticular (23.1, 3.7, 2.1 and 0.8); medial supratesticular (17.2, 4.5, 1.5, and 0.7); distal supratesticular (12.2, 5.7, 0.8, and 0.5); marginal (11.3, 6.5, 0.5, and 0.4); and intratesticular (5.7, 3.5, 0.5, and 0.4). There was a difference between the PSV of the medial and distal supratesticular regions. There were differences in the PSV, EDV, PI and RI among the distal supratesticular, marginal and intratesticular regions. Measurements of PSV, EDV, PI and RI of the testicular artery in dogs at the proposed regions showed different results due to the hemodynamic and morphological differences of the artery during its course in the spermatic cord and to the testicles. It is necessary to identify the region in testicular artery Doppler velocimetric evaluations of dogs, given that there is a difference according to the region measured.

New Approaches to Assess Fertility in Domestic Animals: Relationship between Arterial Blood Flow to the Testicles and Seminal Quality

“…England et al [24] Positive association between PSV at the proximal STA with SVI, VCL and VAP. Trautwein et al [50] PSV was associated with sperm concentration. RI and PI of the STA were inversely associated with sperm membrane integrity.…”

“…In humans, the RI for capsular and intratesticular arteries were smaller than in the STA, while in stallions, values of mean RI in the marginal aspect of the artery were only slightly lower than in the convoluted aspect [23,51]. In dogs, Doppler velocimetry parameters show differences between the spermatic cord, MTA and intratesticular regions, with decreasing velocities as it approaches to testicular parenchyma [48,50]. PSV and EDV show a decreasing trend from STA region to the intra-testicular region, this changes resulted in a decreased RI and PI within the MTA and intratesticular artery [48].…”

“…In several animal species, up to five measurements at different locations of the testicular artery have been done [48,50]. The results of EDV, RI and PI testicular values are influenced by the location of the assessment.…”

Pulsed-wave Doppler Ultrasound in canine reproductive system – Part 2: use in the routine

“…In a study evaluating the blood supply to the testicles, Trautwein et al (2019) subdivided the testicular artery into supratesticular (proximal, medial, distal), marginal, and intratesticular. In the supratesticular region (proximal and medial), the ultrasound waves showed medium to high resistivity with a distinct systolic peak.…”

Advanced ultrasound techniques in small animal reproduction imaging

“…Doppler parameters are also location-depended (Carrillo, Soler, Lucas, & Agut, 2012;de Souza et al, 2014;Gumbsch, Gabler, & Holzmann, 2002;Trautwein, Souza, & Martins, 2019). Not only regional, but important pubertal differences in the blood flow of testicular artery do exist (de Souza, Barbosa, et al, 2015).…”