Ultrasound‐guided injection of the cranial tibial artery for stem cell administration in horses

Abstract

Summary Background A technique for intra‐arterial injection of mesenchymal stem cells (MSC) has been established for front limbs with the use of the median artery. This approach has been proposed for treatment of soft tissue injuries of the equine distal limb. A technique has not been validated yet for hindlimb injection. Objectives To assess the feasibility of injection of the cranial tibial artery in horses, and to evaluate the distribution and persistence of MSC after injection. Study design In vivo experiment. Methods In a first phase, the cranial tibial arteries of both hindlimbs of three research horses were catheterised with ultrasound guidance under general anaesthesia and injected with iodinated contrast. In the second phase, iodinated contrast was injected in three standing sedated horses with ultrasound guidance. In the final phase, 99mTechnetium‐HMPAO labelled allogenic bone marrow derived equine MSC were injected under standing sedation with the same technique in three other horses. Scintigraphy was used to assess MSC distribution and persistence for 24 h. Ultrasound was performed 24 h after injection to assess vessel impairment. Results Arterial injection was achieved in all 18 limbs without any significant complications. Mild partial periarterial injection was observed in four limbs. Scintigraphic images demonstrated diffuse MSC distribution from the tarsal area to the foot. Persistence decreased over time but signal was still present at 24 h. Main limitations Limited retention of the radiolabel in the MSC. Conclusions Ultrasound‐guided injection of the cranial tibial artery can be performed both under general anaesthesia and standing sedation in horses. This technique could be used for MSC treatment of equine proximal suspensory desmopathy or other injuries in the distal hindlimb.

Standing computed tomography of the equine limb using a multi‐slice helical scanner: Technique and feasibility study

“…We did not compare the diagnostic accuracy of CT, which is beyond the scope of the current study. One of the advantages of this CT unit is that the limb can be positioned on a partially non-weightbearing limb and thus Recently, ultrasound-guided injection of median and cranial tibial arteries in standing sedated horses has been described (Spriet et al 2015;Torrent et al 2019). We did not attempt to perform intra-arterial enhanced contrast CT since extra equipment, such as saline chaser, is required for providing a constant infusion of the contrast agent, which may not be practicable in standing horses.…”

Regenerative Medicine for Equine Musculoskeletal Diseases

“…Initially, to treat tendon lesions, MSCs were exclusively applied intralesionally. More recently, it was shown that autologous MSCs applied intravenously, or intra-arterially, may also elicit a beneficial effect in the treatment of tendinopathies when compared with anti-inflammatory drugs [30,[100][101][102].…”

Stem Cells in Veterinary Medicine—Current State and Treatment Options

“…Sole et al (145) observed arterial thrombosis in horses when the intraarterial application of allogeneic BMMSC was performed via IA regional limb perfusion. Interestingly, the complication of thrombosis was not detected when performing IA injection without using a tourniquet, indicating that a thrombosis is a consequence of blood stasis and not the MSC application (147). Similarly, IA injection of MSC was proven feasible with allogeneic equine BMMSC injected into the cranial tibial artery in horses, also without a tourniquet (148).…”