Study tests unsutured needle-core intestinal biopsies in dogs, cats

A new experimental study in Frontiers in Veterinary Science suggests that unsutured intestinal biopsy sites created with an automated needle-core device may withstand pressures above normal physiologic levels in dogs and cats, at least immediately after sampling. Published July 20, 2026, the paper evaluated full-thickness biopsies made with a 16-gauge device and found a mean in vivo initial leakage pressure of 85.66 mmHg, compared with a 25 mmHg reference for maximal physiologic intraluminal pressure. (frontiersin.org)

The question behind the study is a practical one. Full-thickness intestinal biopsies remain important in small animal medicine because they can help distinguish conditions such as inflammatory bowel disease, lymphangiectasia, and intestinal lymphoma, and because some clinically important sites, especially the jejunum and ileum in cats, can be difficult to assess endoscopically. But the tradeoff is surgical risk, particularly biopsy-site dehiscence and septic peritonitis. The authors note that reported postoperative dehiscence rates after full-thickness biopsy have reached as high as 11%, which helps explain why surgeons have traditionally closed biopsy sites routinely. (frontiersin.org)

Against that backdrop, needle-core biopsy has drawn interest as a potentially faster, less invasive alternative to standard incisional biopsy. The Frontiers authors cite prior veterinary work showing the technique can offer reduced surgical time, low complication rates, and good histologic quality when performed via laparotomy with closure of the biopsy site. A Clinician’s Brief summary of that earlier study reported no major complications tied to the needle-core technique, 100% agreement with incisional biopsy for distinguishing lymphoma from inflammatory bowel disease, and significantly shorter collection time, while also noting that one cat died after dehiscence at an incisional biopsy site, not at adjacent needle-core sites. (frontiersin.org)

In the new study, investigators used both cadaveric and in vivo models. Ex vivo, they tested 39 intestinal segments from seven canine and feline cadavers. In vivo, they collected 23 measurements from 12 patients, including eight dogs and four cats, that were already undergoing enterectomy for unrelated indications. The biopsy sites were left unsutured, and intraluminal pressure was increased with methylene blue-stained saline until leakage was first seen. Cadaveric tissue performed poorly, with a mean leakage pressure of 20.7 mmHg and leakage below 25 mmHg in 33 of 39 segments. Live tissue behaved very differently: the mean leakage pressure was 85.66 mmHg, the range was 26.6 to 287.7 mmHg, and every in vivo measurement stayed above 26 mmHg. (frontiersin.org)

That gap between ex vivo and in vivo findings is one of the paper’s most useful takeaways. The authors argue that postmortem changes, including loss of smooth muscle tone and altered tissue properties, likely make cadaveric intestine a poor model for this question. Their conclusion is narrower than a green light to stop suturing: they say the immediate risk of leakage from a roughly 1.3-mm unsutured needle-core defect appears low in live dogs and cats, but they explicitly state that the necessity of routine closure cannot be settled from these data because healing and longer-term integrity were not studied. (frontiersin.org)

Expert reaction specific to this new paper was limited in publicly available coverage at the time of writing. Still, the broader clinical conversation has been moving toward techniques that can reduce invasiveness without sacrificing diagnostic yield. Clinician’s Brief, summarizing earlier work in this area, highlighted the potential for needle-core sampling to simplify laparoscopic intestinal biopsy and recommended an antimesenteric approach with a 45-degree insertion angle to reduce the risk of mesenteric injury and possibly leakage. That doesn’t validate unsutured use on its own, but it does show that the profession has already been exploring how to make intestinal sampling more efficient and less traumatic. (cliniciansbrief.com)

Why it matters: For veterinary professionals, this study is less about changing practice tomorrow than about refining the risk-benefit equation around intestinal diagnostics. If future clinical studies confirm that tiny needle-core defects can safely remain unclosed in selected patients, that could shorten procedures, reduce tissue handling, and expand minimally invasive options, including laparoscopic-assisted or even image-guided approaches. But the current evidence stops at immediate mechanical integrity in mostly nondiseased tissue adjacent to enterectomy sites. That means surgeons should be careful not to overgeneralize these findings to fragile, inflamed, infiltrated, or poorly perfused bowel, where healing biology, not just pressure tolerance, determines outcome. (frontiersin.org)

What to watch: The important next milestone will be prospective clinical outcome data, ideally in patients undergoing diagnostic biopsy for intestinal disease, with follow-up for leakage, dehiscence, peritonitis, and histologic adequacy before anyone can argue that routine closure should be abandoned. (frontiersin.org)