Mixed Reality for Veterinary Medicine: Case Study of a Canine Femoral Nerve Block.

The femoral nerve blockage is a procedure that aims to provide anesthesia to the hip, anterior thigh, and stifle. This procedure presents several challenges when performed in veterinary patients with diverse anatomy and physiology. Successful use of this technique will improve a dog's recovery time after surgery in comparison to the commonly used epidural block. A mixed reality application to guide practitioners in the femoral nerve block procedure was developed in Unity and Visual Studio. A 3D model for use within the application was created from pictures of a cadaver leg using photogrammetry software. The Microsoft HoloLens headset provides the mixed reality hardware platform. This paper presents the workflow used in developing the mixed reality application and custom 3D model, as well as initial results with respect to the utility of the application in guiding an anesthesiologist in the procedure of the femoral nerve block.

Evaluation of ovarian volume by transrectal ultrasonography in cattle; affect of the day of the estrous cycle and validation of a method of subtracting of corpora lutea and follicle volume.

This research was conducted to evaluate a method for determining ovarian volume using ultrasonography; specifically, how the day of the estrous cycle affected ovarian volume, and the application of a formula for adjusted ovarian volume (ADJ VOL) and its relationship to actual ovarian volume. Cows (n = 22) were estrous synchronized and subjected to serial transrectal ultrasonographic evaluations, performed every 48 h from the day prior to ovulation until day 9 of the subsequent estrous cycle. Measurements obtained from recorded ultrasonographic images were used to determine actual ovarian volume cm3 = [0.523 X (D1 X D2 X D3)] and adjusted ovarian volume (ADJ VOL) cm3 = [0.523 X (D1 X D2 X D3)]- 43 (πrCL2) - 43 (πrF2) on days 1, 3, 5, 7, 9 of the estrous cycle. A third objective was to evaluate the concordance correlation coefficient (ρc) between post-mortem ovarian measurements and the water displacement test. Ovarian volume increased with each day of the estrous cycle from Day 1 to Day 7. Day of the estrous cycle affected ovarian volume (P <  0.001). When applying the formula for ADJ VOL, there was not an effect of day of the estrous cycle (P  = 0.509). Ovarian volume, results ex-vivo, were very consistent with the displacement volume results (ρc = 0.942). If large ovarian structures are present, and the day of the estrous cycle is unknown, then the formula for ADJ VOL can be used to estimate ovarian volume on Day 1 of the estrous cycle.

Ulnar ostectomy decreases the stability of canine cadaver carpi as assessed with stress radiography.

Distal ulnar ostectomy may be performed palliatively in patients with distal ulnar osteosarcoma. Concurrent arthrodesis of the carpus has been proposed to counteract joint instability following transection of carpal ligaments associated with removal of the distal ulna. The objective of this prospective one group pretest, posttest study was to assess stability of the carpus following distal ulnar ostectomy using pre- and postoperative stress radiographic views in a group of canine cadaver limbs. Seven thoracic limbs from six canine cadavers weighing more than 20 kg were obtained. Lateral and dorsopalmar, extended lateral, medial stress, and lateral stress radiographs were made before and after distal ulnar ostectomy. Presurgical canine cadaver carpal angle measurements were as follows (mean ± standard deviation): extension 205.9° ± 5.4; medial stress 25.1° ± 5.7; and lateral stress 13.3° ± 5.2°. Cadaver limb joint angles exceeded those previously reported in live dogs. A significant increase in carpal angle was noted following ulnar ostectomy. The mean increases in carpal angle were as follows: (mean ± standard deviation (95% confidence interval)): extension 6.2° ± 4.9 (2.6-9.8) (P = 0.007); medial stress 3.2° ± 3.0 (1.0-5.5) (P = 0.015); lateral stress 6.2° ± 5.2 (2.4-10.1) (P = 0.010). Findings from this cadaver study support the use of supplementary stabilization for clinical patients undergoing distal ulnar ostectomy. Future studies are needed in clinical patients to evaluate changes in limb positioning and gait associated with distal ulnar ostectomy.

Association of unmeasured strong ions with outcome of hospitalized beef and dairy diarrheic calves.

Increased systemic concentrations of L-lactate and unmeasured strong ions (USI) are associated with an increased risk of mortality in human neonates and adults suffering from various diseases. This exploratory study aimed to investigate if values of certain acid-base parameters, especially L-lactate and USI, on admission to hospital are associated with mortality in diarrheic calves. Fifty-five calves < 28 days old admitted to 2 teaching hospitals for diagnosis and treatment of diarrhea were included. Admission demographic, physical examination, blood gas and biochemistry analysis, and outcome data were recorded. Admission acid-base values associated with outcome were assessed using multivariable regression modeling. Calves with elevated plasma L-lactate (OR: 1.30, 95% CI: 1.08 to 1.55; P = 0.005) and USI (OR: 1.40, 95% CI: 1.12 to 1.74; P = 0.003) at admission were more likely to die or to be euthanized. This study revealed that elevated concentrations of L-lactate and USI at admission were positively associated with mortality.

Association des ions forts non mesurés avec les résultats des veaux de boucherie et laitiers diarrhéiques hospitalisés. Des concentrations systémiques accrues de L-lactate et des ions forts non mesurés (IFN) sont associées à un risque accru de mortalité chez les nouveau-nés humains et les adultes souffrant de diverses affections. Cette étude exploratoire visait à vérifier si les valeurs de certains paramètres acides, particulièrement L-lactate et IFN, à l'admission à l'hôpital sont associées à la mortalité chez les veaux diarrhéiques. Cinquante-cinq veaux âgés de < 28 jours admis à deux hôpitaux d'enseignement pour le diagnostic et le traitement ont été inclus. Les données démographiques, l'examen physique, les valeurs des gaz sanguins et de l'analyse biochimique du sang ainsi que l'issu des animaux ont été consignés. Les valeurs de l'équilibre acide-base à l'admission associées à l'issu des animaux ont été évaluées en utilisant une modélisation de régression multi-variable. Il était plus probable que les veaux avec du L-lactate plasmatique élevé (RC : 1,30, IC 95 %, 1,08 à 1,55; P = 0,005) et IFN (RC : 1,40, IC de 95 %, 1,12 à 1,74; P = 0,003), à l'admission meurent ou soient euthanasiés. Cette étude a révélé que des concentrations élevées de L-lactate et d'IFN à l'admission étaient positivement associées à la mortalité.(Traduit par Isabelle Vallières).

Effect of distal ulnar ostectomy on carpal joint stability during weight bearing in the dog.

OBJECTIVE: To assess the influence of a 50% distal ulnectomy on mediolateral carpal stability in the dog. STUDY DESIGN: Canine cadaveric study. SAMPLE POPULATION: Seven canine thoracic limbs METHODS: Thoracic limbs were placed in a jig to mimic weight bearing with a load representing 30% of body weight. Carpal extension angle was standardized at 190° ± 5°. Frontal plane carpal angles were measured with the limb loaded on craniocaudal radiographs before and after ulnectomy. Valgus and varus stress radiographs with the limb loaded were acquired before and after ulnectomy. The limbs were palpated and were subjectively graded for valgus or varus instability by 2 investigators before and after ulnectomy. RESULTS: Mean (±SD) valgus angulation increased after ulnectomy (2.1° ± 1.7°; P = .017; CI95 = 0.5°-3.7°) when the limb was loaded without valgus or varus stress applied. Mean valgus angulation increased after ulnectomy (2.7° ± 2.8°; P = .032; CI95 = -0.2°-5.5°) when valgus stress was applied to the loaded limb. Varus angulation was unchanged after ulnectomy (0.6° ± 4.6°; P = .383; CI95 = -4.2°-5.3°) when varus stress was applied to the loaded limb. Palpation detected increased valgus score after ulnectomy. CONCLUSION: Distal ulnectomy with excision of the lateral styloid process induces a slight increase in valgus in canine cadaver carpi. The clinical consequences of that valgus on carpal function and health should be assessed in clinical patients.

Unilateral notomelia in a newborn Holstein calf.

A 24-hour-old Holstein bull calf with notomelia was donated to the Atlantic Veterinary College. The extra limb was on the right side of the caudal neck adjacent to the withers. The limb was surgically removed under general anesthesia. The calf was adopted and discharged with no complications.

Notomélie unilatérale chez un veau Holstein nouveau-né. Un veau taureau Holstein âgé de 24 heures atteint de notomélie a été donné à l'Atlantic Veterinary College. Le membre supplémentaire se trouvait du côté droit du cou caudalement au garrot. Le membre a été enlevé par chirurgie sous anesthésie générale. Le veau a été adopté et a reçu son congé sans complications.(Traduit par Isabelle Vallières).

The selenium and vitamin E status of horses in Prince Edward Island.

Serum selenium (Se), vitamin E, and resting thyroid hormone concentrations were measured in 201 horses in Prince Edward Island (PEI). Selenium concentrations were either marginal (0.0053 to 0.1200 ppm) or deficient (< 0.0053 ppm) in 79% of horses based on current reference ranges for Se in serum. Aged and young adult pleasure horses had a higher prevalence of inadequate Se concentrations compared to racehorses and broodmares (82% and 97% versus 45% and 72%, respectively). Overall, 13% of horses had inadequate (< 200 µg/dL) serum vitamin E concentrations; most of these were young pleasure horses. No horses were hypothyroid and, contrary to findings in other species, there was a positive relationship between serum thyroxine and Se concentrations (P < 0.05). We conclude that Se deficiency is widespread in PEI horse populations, especially in pleasure horses, and vitamin E deficiency is more common in young pleasure horses. Micronutrient supplementation practices employed by PEI horse owners appear inadequate to ensure sufficiency.

Isolation of Escherichia fergusonii from the feces and internal organs of a goat with diarrhea.

A fecal sample from a 42-year-old goat with a 2-month history of poor weight gain and diarrhea yielded a moderate growth of an organism resembling Salmonella spp. on MacConkey agar. The organism was identified as Escherichia fergusonii. The animal was euthanized. Samples of intestine, lung, liver, and kidney yielded the same organism, E. fergusonii.

Transcutaneous ultrasonographic evaluation of gastric distension with fluid in horses.

OBJECTIVE: To develop a transcutaneous ultrasonography (TUS) method for measuring the location of the stomach during various levels of fluid distension and evaluate any correlation between gastric fluid distension and stomach position. ANIMALS: 6 adult horses. PROCEDURES: Known volumes of water were administered in 2 trials. In trial 1, the stomach was evaluated prior to and after the administration of 2, 4, and 6 L of water. In trial 2, the stomach was evaluated after administration of 6, 8, 10, and 12 L of water. The TUS was performed at the 7th through 16th left intercostal spaces (ICSs). For each volume of water, an image was captured at the most dorsal point in each ICS where the dorsolateral aspect of the stomach wall was viewed. The distance between this point and a horizontal line drawn on the skin at the level of the elbow joint was measured. The measurements at all ICSs were used to estimate the gastric wall height at ICS 12, which was subsequently evaluated for statistical association with volume administered. RESULTS: Significant correlation between the estimated height of the stomach wall at ICS 12 and the volume of fluid administered was detected. A regression equation to estimate gastric fluid volume when initial values for gastric wall height (cm) at ICS 12 and fluid volume (L) are known was developed. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that use of TUS for gastric fluid volume estimation is a potentially useful technique.

Osteochondrosis of the occipital condyles and atlanto-occipital dysplasia in a Belgian horse.

A lesion in the cervical region of a 14-month-old Belgian gelding with severe ataxia was suspected. Necropsy revealed symmetric focal cartilage defects compatible with osteochondrosis of the occipital condyles and atlanto-occipital dysplasia. To our knowledge this is the first equine report of symmetrical osteochondrosis of the occipital condyles causing neurologic signs.