FREE SHIPPING over $40
OVER 9000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Home / Equine Research Bank / Vet Radiol Ultrasound / Resistivity and Pulsatility Indexes Renal Values Do Not Diff...
Veterinary radiology & ultrasound : the official journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association2025; 66(2); e70023; doi: 10.1111/vru.70023

Resistivity and Pulsatility Indexes Renal Values Do Not Differ When Obtained from Abdominal or Transrectal Approaches in Healthy Horses.

Abstract: Early detection of renal deficient function is imperative for the success of treatments and determining prognosis. In horses, a renal ultrasound can be performed through the abdominal wall (TA) or transrectally (TR), being an important tool for the evaluation of the kidneys. Besides renal morphology, resistivity (RI) and pulsatility indexes (PI) may be early tools to detect renal injury as they reflect arterial compliance. Twenty-nine healthy adult horses were sonographically evaluated by TA and TR approaches, measuring RI and PI on both kidneys. The mean values from the TA for RI and PI in the right kidney were, respectively, 0.577 ± 0.072 and 0.950 ± 0.182, and 0.553 ± 0.077 and 0.884 ± 0.163 in the left kidney. As for the TR, the mean values for RI and PI in the right kidney were 0.543 ± 0.096 and 0.848 ± 0.212, respectively, and 0.551 ± 0.089 and 0.888 ± 0.204 in the left kidney. No differences (two-way ANOVA) were observed between the left and right kidneys [RI (p = .31) and PI (p = .24)] nor between techniques for both RI and PI, being relevant to state that data on the right kidney by the TR technique did not allow a reliable statistical evaluation. Obtaining good quality TR images in larger horses and satisfactory TA images in obese horses were important differences for each examination technique. In conclusion, there were no differences in RI and PI values obtained from abdominal or transrectal approaches.
© 2025 American College of Veterinary Radiology.
Get Full Text
Publication Date: 2025-03-13 PubMed ID: 40077881DOI: 10.1111/vru.70023Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research paper examines whether there is any difference in tissue resistance and pulsatility indexes in the kidneys of healthy horses when evaluated via abdominal and transrectal ultrasonic methods. The study found no significant difference in these indexes between the two techniques.

Objectives and Importance of the Study

  • This investigation was carried out to discern the differences in resistive (RI) and pulsatility indexes (PI) of horses’ kidneys when assessed transabdominally (TA) or transrectally (TR).
  • The early detection of renal deficiencies drastically improves the prognosis and success of potential treatments. Therefore, gaining an accurate understanding of a horse’s kidney health is essential.
  • The study is significant as it examines the differences between two common veterinary methods for measuring RI and PI. The results found could help practitioners choose the most suitable procedure for their patients.

Methodology

  • Twenty-nine healthy adult horses participated in the study, in which both the TA and TR approaches were used for ultrasonic evaluation.
  • RI and PI were measured on both the right and left kidneys of the horses for each method.
  • The data was analyzed using a two-way ANOVA statistical test to observe any differences between the left and right kidneys and between the two techniques.

Findings

  • No significant differences were found in the RI and PI values obtained from the TA or TR approaches.
  • Regardless of the method used, the RI and PI values remained consistent, suggesting that either procedure could be used interchangeably without affecting the results.
  • However, the researchers noted difficulties obtaining reliable TR images in larger horses and satisfactory TA images in obese horses, thus the physical attributes of the horse may impact the selection of the examination technique.

Conclusions

  • In summary, the study concludes that both the TA and TR ultrasonic evaluation methods are similarly effective in assessing the RI and PI of horses’ kidneys.
  • This information could influence veterinary approaches to kidney health assessments, as either method could provide reliable information about a horse’s kidney health. However, it also suggests that the horse’s size and obesity status should be considered when choosing an evaluation method.

Cite This Article

APA
Rosse NDS, Tavares RA, Nunes MC, de Freitas BW, Reis ECC. (2025). Resistivity and Pulsatility Indexes Renal Values Do Not Differ When Obtained from Abdominal or Transrectal Approaches in Healthy Horses. Vet Radiol Ultrasound, 66(2), e70023. https://doi.org/10.1111/vru.70023

Publication

Veterinary radiology & ultrasound : the official journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association
ISSN: 1740-8261
NlmUniqueID: 9209635
Country: England
Language: English
Volume: 66
Issue: 2
Pages: e70023

Researcher Affiliations

Rosse, Nathalia Dos Santos
  • Department of Veterinary Medicine, Federal University of Viçosa, Minas Gerais, Brazil.
Tavares, Rachel de Andrade
  • Department of Veterinary Medicine, Federal University of Viçosa, Minas Gerais, Brazil.
Nunes, Maria Clara
  • Department of Veterinary Medicine, Federal University of Viçosa, Minas Gerais, Brazil.
de Freitas, Bruna Waddington
  • Department of Veterinary Medicine, Federal University of Viçosa, Minas Gerais, Brazil.
Reis, Emily Correna Carlo
  • Department of Veterinary Medicine, Federal University of Viçosa, Minas Gerais, Brazil.

MeSH Terms

  • Animals
  • Horses / physiology
  • Kidney / diagnostic imaging
  • Male
  • Female
  • Pulsatile Flow
  • Ultrasonography / veterinary
  • Abdomen / diagnostic imaging
  • Rectum / diagnostic imaging
  • Reference Values
  • Vascular Resistance

Grant Funding

  • 001 / Coordenau00e7u00e3o de Aperfeiu00e7oamento de Pessoal de Nu00edvel Superior

References

This article includes 37 references
  1. Toribio RE. Essentials of Equine Renal and Urinary Tract Physiology. Veterinary Clinics of North America: Equine Practice 23, no. 3 (2007): 533–561.
  2. Verlander JW, Klein BG. Section VII Renal physiology. Cunningham's Textbook of Veterinary Physiology 5th edition (Missouri: Elsevier Saunders, 2013): 460–494.
  3. Novellas R, Espada Y, de Gopegui RR. Doppler Ultrasonographic Estimation of Renal and Ocular Resistive and Pulsatility Indices in Normal Dogs and Cats. Veterinary Radiology & Ultrasound 48, no. 1 (2007): 69–73.
  4. Radermacher J, Ellis S, Haller H. Renal Resistance Index and Progression of Renal Disease. Hypertension 39, no. 2 (2002): 699–703.
  5. Platt JF. Duplex Doppler Evaluation of Native Kidney Dysfunction: Obstructive and Nonobstructive Disease. AJR American Journal of Roentgenology 158, no. 5 (1992): 1035–1042.
  6. Nyland TG, Fisher PE, Doverspike M, Hornof WJ, Olander HJ. Diagnosis of Urinary Tract Obstruction in Dogs Using Duplex Doppler Ultrasonography. Veterinary Radiology & Ultrasound 34, no. 5 (1993): 348–352.
  7. Dalley CA, Finn‐Bodner S, Lenz SD. Contrast‐induced Renal Failure Documented by Color‐Doppler Imaging in a Dog. Journal of the American Animal Hospital Association 30 (1994): 33–37.
  8. Morrow KL, Salman MD, Lappin MR, Wrigley R. Comparison of the Resistive Index to Clinical Parameters in Dogs With Renal Disease. Veterinary Radiology & Ultrasound 37, no. 3 (1996): 193–199.
  9. Novellas R, De Gopegui RR, Espada Y. Assessment of Renal Vascular Resistance and Blood Pressure in Dogs and Cats With Renal Disease. Veterinary Record 166, no. 20 (2010): 618–623.
  10. Evangelista GC, Dornelas LR, Cintra CC. Evaluating Feline Lower Urinary Tract Disease: Doppler Ultrasound of the Kidneys. Journal of Feline Medicine and Surgery 25 (2023): 1098612×2211454–9.
  11. De Sousa Alves A, Henrique FV, Araújo SB. Renal Resistivity Index as an Aid in the Diagnosis of Acute Kidney Injury in Bitches With Pyometra. Acta Veterinaria Brasilica 15, no. 3 (2021): 225–228.
  12. Grauer GF. Early Detection of Renal Damage and Disease in Dogs and Cats. Veterinary Clinics: Small Animal Practice 35, no. 3 (2005): 581–596.
  13. Szczepankiewicz B, Pasławska U, Siwińska N, Plens K, Pasławski R. Evaluation of the Diagnostic Value of the Renal Resistive Index as a Marker of the Subclinical Development of Cardiorenal Syndrome in MMVD Dogs. Journal of the Renin‐Angiotensin‐Aldosterone System 22, no. 1 (2021): 1–10.
  14. Matos I, Azevedo P, Carreira LM. Pilot Study to Evaluate the Potential Use of the Renal Resistive Index as a Preliminary Diagnostic Tool for Chronic Kidney Disease in Cats. Journal of Feline Medicine and Surgery 20, no. 10 (2018): 940–947.
  15. Moarabi A, Hanafi MG, Mosallanejad B, Alimardani P. Measurement of Normal Renal Artery Indices in DSH Cats by Doppler Ultrasonography. Iranian Veterinary Journal 17, no. 4 (2022): 103–110.
  16. Petersen LJ, Petersen JR, Talleruphuus U, Ladefoged SD, Mehlsen J, Jensen HA. The Pulsatility Index and the Resistive Index in Renal Arteries. Associations With Long‐term Progression in Chronic Renal Failure. Nephrology, Dialysis, Transplantation: Official Publication of the European Dialysis and Transplant Association‐European Renal Association 12, no. 7 (1997): 1376–1380.
  17. Harzmann R, Weckermann D. Importance of Doppler Sonography in Urology (With 1 color plate). Urologia Internationalis 45, no. 4 (1990): 258–263.
  18. Santos SN, Leite LR, Tse TS, Beck R, Lee RA, Shepherd RF. Renal Resistance Index Predicting Outcome of Renal Revascularization for Renovascular Hypertension. Arquivos Brasileiros De Cardiologia 94 (2010): 452–456.
  19. Freeman SL. Diagnostic Ultrasonography of the Mature Equine Abdomen. Equine Veterinary Education 15, no. 6 (2003): 319–330.
  20. Macrì F, Pugliese M, Di Pietro S. Doppler Ultrasonographic Estimation of Renal Resistive Index in Horse: Comparison Between Left and Right Kidneys. Journal of Equine Veterinary Science 35, no. 2 (2015): 111–115.
  21. Siwinska N, Zak A, Slowikowska M, Szczepankiewicz B, Niedzwiedz A, Paslawska U. An Assessment of the Utility and Repeatability of the Renal Resistive Index in Horses. PLoS ONE 14, no. 12 (2019): e0226941.
  22. Freccero F, Petrucelli M, Cipone M, Nocera I, Sgorbini M. Doppler Evaluation of Renal Resistivity Index in Healthy Conscious Horses and Donkeys. PLoS ONE 15, no. 2 (2020): e0228741.
  23. Siwinska N, Zak A, Slowikowska M, Paslawska U. Renal Resistive Index as a Potential Indicator of Acute Kidney Injury in Horses. Journal of Equine Veterinary Science 103 (2021): 103662.
  24. Hoffmann KL, Wood AK, Kirby AC. Use of Doppler Ultrasonography to Evaluate Renal Arterial Blood Flow in Horses. American Journal of Veterinary Research 58, no. 7 (1997): 697–701.
  25. Blissitt KJ, Bonagura JD. Pulsed Wave Doppler Echocardiography in Normal Horses. Equine Veterinary Journal 27, no. S19 (1995): 38–46.
  26. Decloedt A, Verheyen T, Sys S, De Clercq D, Van Loon G. Evaluation of Tissue Doppler Imaging for Regional Quantification of Radial Left Ventricular Wall Motion in Healthy Horses. American Journal of Veterinary Research 74, no. 1 (2013): 53–61.
  27. Wongaumnuaykul S, Siedler C, Schobesberger H, Stanek C. Doppler Sonographic Evaluation of the Digital Blood Flow in Horses With Laminitis or Septic Pododermatitis. Veterinary Radiology & Ultrasound 47, no. 2 (2006): 199–205.
  28. Douthit TL, Bormann JM, Bello NM. Assessing the Association Between Hoof Thermography and Hoof Doppler Ultrasonography for the Diagnosis of Lameness in Horses. Journal of Equine Veterinary Science 34, no. 2 (2014): 275–280.
  29. Ortega‐Ferrusola C, Gracia‐Calvo L, Ezquerra J, Pena FJ. Use of Colour and Spectral Doppler Ultrasonography in Stallion Andrology. Reproduction in Domestic Animals 49 (2014): 88–96.
  30. Ginther OJ, Utt MD. Doppler Ultrasound in Equine Reproduction: Principles, Techniques, and Potential. Journal of Equine Veterinary Science 24, no. 12 (2004): 516–526.
  31. Witt MC, Bollwein H, Probst J, Baackmann C, Squires EL, Sieme H. Doppler Sonography of the Uterine and Ovarian Arteries During a Superovulatory Program in Horses. Theriogenology 77, no. 7 (2012): 1406–1414.
  32. Schnell D, Darmon M. Renal Doppler to Assess Renal Perfusion in the Critically Ill: A Reappraisal. Intensive Care Medicine 38, no. 11 (2012): 1751–1760.
  33. Rivers BJ, Walter PA, O'brien TD, Polzin DJ. Duplex Doppler Estimation of Pourcelot Resistive Index in Arcuate Arteries of Sedated Normal Cats. Journal of Veterinary Internal Medicine 10, no. 1 (1996): 28–33.
  34. Rivers BJ, Walter PA, Polzin DJ, King VL. Duplex Doppler Estimation of Intrarenal Pourcelot Resistive Index in Dogs and Cats With Renal Disease. Journal of Veterinary Internal Medicine 11, no. 4 (1997): 250–260.
  35. Dos Santos Rosse N, Reis ECC. Doppler Renal Resistivity Index in Horses: A Systematic Review. Equine Veterinary Journal 57, no. 2 (2025): 303–311.
  36. Di Nicolò P, Granata A. Renal Resistive Index: Not Only Kidney. Clinical and Experimental Nephrology 21, no. 3 (2017): 359–366.
  37. Kuznetsova T, Cauwenberghs N, Knez J. Doppler Indexes of Left Ventricular Systolic and Diastolic Flow and central Pulse Pressure in Relation to Renal Resistive Index. American Journal of Hypertension 28, no. 4 (2015): 535–545.

Citations

This article has been cited 0 times.
Subscribe to our newsletter
Join 99,001 horse owners like you who receive our email updates on horse health and nutrition.