Incidence of Z, I and B Lines Detected with Point of Care Ultrasound in Healthy Shelter Dogs
Â. Martin; D. Gouveia; A. Cardoso; I. Viegas; V. Busoni; K. Gommeren; S. Boysen
Introduction: Lung ultrasound has been described in dogs, although Z and I lines, which are present in healthy humans, have never been reported. Z lines are ill-defined artifacts arising from the pleural line, independent of the glide sign, not erasing A-Lines, and vanish after a few centimeters (2–5 cm), without pathologic significance. I lines have similarities with B-lines, arising from the lung surface, moving with the glide sign, but disappearing after 3–4 cm. They are short vertical artifacts of unknown clinical significance.
Objective: To describe lung ultrasound findings in a population of healthy shelter dogs using a combined pleural space and lung ultrasound protocol. We hypothesize that shelter dogs have B, Z and I lines present on lung ultrasound.
Methods: Shelter dogs prospectively underwent physical examination, three view thoracic radiographs and thoracic VPOCUS. Dogs with normal physical exam findings, unremarkable pulmonary thoracic radiographs and normal VPOCUS findings were included in the study. VPOCUS involved evaluation of the pleural space and lung, with cineloops recorded at 17 different locations.
Results: 53 dogs were enrolled. 13 dogs had 1 (n=9), 2 (n=2) or 3 (n=2) total B lines. Of the dogs with 2 B lines, one had a B line at 2 sites, and one had 2 B lines at a single site. Of the dogs with 3 total B lines, 1 had a B line at 3 sites and one had 3 at a single site. No dog had subpleural consolidation. All dogs had Z lines noted with a median of 11 (range 1–20). 43/53 dogs had a median of 3 (range 1–10) I lines noted.
Discussion: Z and I lines occur frequently in healthy dogs. They are important to identify as they can be confused for B lines. The significance of I lines is uncertain. B lines were identified in up to 25% of healthy shelter dogs, which is similar to previous reports.
Conclusion: Similar to reports in healthy humans, Z and I-lines appear to be common findings in healthy shelter dogs. The incidence of B lines in shelter dogs is similar to the incidence in other healthy dog populations.