Clinical safety of computed tomography-guided injection of autologous muscle-derived mesenchymal stem cells in the intervertebral disc in dogs.

Background: Pre-clinical randomized controlled animal trials have been conducted to evaluate the effect of mesenchymal stem cell (MSCs) transplantation on intervertebral disc (IVD) degeneration. MSCs can be obtained from different tissues, but systematic studies concerning the effects of muscle-derived MSCs injections on canine naturally degenerated IVD are still lacking. The aim of this study is the assessment of the clinical safety of this technique and its effects on the imaging features of the lumbosacral IVD. Methods: Eight adult healthy Beagle dogs were used in this study. In the preliminary phase, viability of muscle-derived MSCs in presence of contrast medium was assessed. In the clinical assessment phase, MSCs were injected in the lumbosacral IVD by computed-tomography (CT) guidance, after the injection of contrast medium to assess the correct intradiscal needle position. Regular clinical examinations were performed and pre- and post-injections (CT) and magnetic resonance imaging (MRI) features of the IVD were assessed. Results: The percentage of viability of MSCs in the presence of contrast medium ranged from 90 to 98%. 3x106 MSCs were obtained from six dogs and injected in the IVD. No major or minor complications were reported during the procedure and no abnormalities were noticed during the clinical examinations. No statistically significant variations were noticed between the pre- and post-injections imaging features. Conclusion: This technique is clinically safe and it is not associated with any progression of the IVD degeneration, detected by CT and MRI imaging.

Clinical effects of computed tomography-guided lumbosacral facet joint, transforaminal epidural, and translaminar epidural injections of methylprednisolone acetate in healthy dogs.

OBJECTIVE To determine clinical effects of CT-guided lumbosacral facet joint, transforaminal epidural, and translaminar epidural injections of methylprednisolone acetate in healthy dogs. ANIMALS 15 healthy Beagles. PROCEDURES Dogs were randomly assigned to 3 groups (5 dogs/group) and received a single CT-guided lumbosacral facet joint, transforaminal epidural, or translaminar epidural injection of methylprednisolone acetate (0.1 mg/kg). Contrast medium was injected prior to injection of methylprednisolone to verify needle placement. Neurologic examinations were performed 1, 3, 7, and 10 days after the injection. In dogs with neurologic abnormalities, a final neurologic examination was performed 24 days after the procedure. RESULTS Methylprednisolone injections were successfully performed in 14 of the 15 dogs. In 1 dog, vascular puncture occurred, and the methylprednisolone injection was not performed. No major or minor complications were identified during or immediately after the procedure, other than mild transient hyperthermia. During follow-up neurologic examinations, no motor, sensory, or postural deficits were identified, other than mild alterations in the patellar, withdrawal, cranial tibial, and perineal reflexes in some dogs. Overall, altered reflexes were observed in 11 of the 14 dogs, during 27 of 65 neurologic examinations. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that CT-guided lumbosacral facet joint, transforaminal epidural, and translaminar epidural injections of methylprednisolone acetate were associated with few complications in healthy dogs. However, the number of dogs evaluated was small, and additional studies are needed to assess clinical efficacy and safety of these procedures.

TECHNIQUE, DIFFICULTY, AND ACCURACY OF COMPUTED TOMOGRAPHY-GUIDED TRANSLAMINAR AND TRANSFORAMINAL LUMBOSACRAL EPIDURAL AND INTRAARTICULAR LUMBAR FACET JOINT INJECTIONS IN DOGS.

In human medicine, spinal pain and radiculopathy are commonly managed by computed tomography (CT)-guided facet joint injections and by transforaminal or translaminar epidural injections. In dogs, CT-guided lumbosacral epidural or lumbar facet joint injections have not been described. The aim of this experimental, ex vivo, feasibility study was to develop techniques and to assess their difficulty and accuracy. Two canine cadavers were used to establish the techniques and eight cadavers to assess difficulty and accuracy. Contrast medium was injected and a CT scan was performed after each injection. Accuracy was assessed according to epidural or joint space contrast opacification. Difficulty was classified as easy, moderately difficult, or difficult, based on the number of CT scans needed to guide insertion of the needle. A total of six translaminar and five transforaminal epidural and 53 joint injections were performed. Translaminar injections had a high success rate (100%), were highly accurate (75%), and easy to perform (100%). Transforaminal injections had an moderately high success rate (75%), were accurate (75%), and moderately difficult to perform (100%). Success rate of facet joint injections was 62% and was higher for larger facet joints, such as L7-S1. Accuracy of facet joint injections ranged from accurate (37-62%) to highly accurate (25%) depending on the volume injected. In 77% of cases, injections were moderately difficult to perform. Possible complications of epidural and facet joint injections were subarachnoid and vertebral venous plexus puncture and periarticular spread, respectively. Further studies are suggested to evaluate in vivo feasibility and safety of these techniques.

Feasibility of ultrasound-guided epidural access at the lumbo-sacral space in dogs.

Epidural injections are commonly performed blindly in veterinary medicine. The aims of this study were to describe the lumbosacral ultrasonographic anatomy and to assess the feasibility of an ultrasound-guided epidural injection technique in dogs. A cross sectional anatomic atlas of the lumbosacral region and ex vivo ultrasound images were obtained in two cadavers to describe the ultrasound anatomy and to identify the landmarks. Sixteen normal weight canine cadavers were used to establish two variations of the technique for direct ultrasound-guided injection, using spinal needles or epidural catheters. The technique was finally performed in two normal weight cadavers, in two overweight cadavers and in five live dogs with radiographic abnormalities resulting of the lumbosacral spine. Contrast medium was injected and CT was used to assess the success of the injection. The anatomic landmarks to carry out the procedure were the seventh lumbar vertebra, the iliac wings, and the first sacral vertebra. The target for directing the needle was the trapezoid-shaped echogenic zone between the contiguous articular facets of the lumbosacral vertebral canal visualized in a parasagittal plane. The spinal needle or epidural catheter was inserted in a 45° craniodorsal-caudoventral direction through the subcutaneous tissue and the interarcuate ligament until reaching the epidural space. CT examination confirmed the presence of contrast medium in the epidural space in 25/25 dogs, although a variable contamination of the subarachnoid space was also noted. Findings indicated that this ultrasound-guided epidural injection technique is feasible for normal weight and overweight dogs, with and without radiographic abnormalities of the spine.

Molecular identification and pathology of Anisakis pegreffii (Nematoda: Anisakidae) infection in the Mediterranean loggerhead sea turtle (Caretta caretta).

Nematodes of genus Anisakis spp. parasitize a wide range of marine hosts with marine mammals (mainly cetaceans) serving as definitive hosts, while fish, squid and other invertebrates serve as paratenic or intermediate hosts. Sea turtles can act as accidental or paratenic hosts for Anisakis spp. larvae, harbouring third-stage larvae unable to complete their life cycle in an ectothermic vertebrate. Post-mortem examination of 96 loggerhead sea turtles (Caretta caretta) stranded along the Italian coast of the Mediterranean Sea showed infection by Anisakis larvae Type I from 4 of 6 locations that were identified as belonging to Anisakis pegreffii by sequence analyses of the mtDNA cox2. Thirteen turtles (11 males and 2 females) were infected with A. pegreffii. Larvae were detected through gross necroscopy from 7 turtles, while in other 6 positive loggerhead sea turtles A. pegreffii larvae were revealed by histopathology. Pathological changes associated with A. pegreffii larvae in the stomach and intestine included necrosis and granulomatous response compatible with larvae migration. The role of the loggerhead sea turtle as an accidental host in the life cycle of this nematode is also discussed. This study is the first description of pathological changes associated with A. pegreffii in a sea turtle.