Evaluation of Thermographic Imaging in Canine Hindlimb Muscles After 6 Min of Walking-A Pilot Study.

Objective: To evaluate changes in superficial temperature of hindlimb muscles before and after a 6-min walk in healthy dogs. Methods: Two infrared thermographic images were captured of the proximal and distal hindlimbs of 11 healthy dogs before and after a 6-min walk. Orthopedic exam and objective gait analysis confirmed the healthy status of study subjects. Superficial temperatures of the gastrocnemius, biceps femoris, and gracilis were assessed. Analysis of images was performed using 2 different methods of region of interest (ROI) selection. ROI were selected first using one point (single pixel) in the muscle and then separately by selecting a line (LN) corresponding to many points of each muscle belly from which an average was taken. P < 0.05 was considered significant. Results: There was no significant change in temperature using point ROI before and after 6 min of walking of the gastrocnemius, gracilis, and biceps femoris muscles (p = 0.273, p = 0.349, p = 0.351, respectively). Using linear ROI, both biceps femoris and gracilis muscles exhibited significant increases in temperature (p < 0.0001, p = 0.032, respectively). There was no significant increase in temperature of gastrocnemius muscle for both point and linear ROI selection (p = 0.273, p = 0.448, respectively). The right biceps femoris temperatures were higher compared to left biceps femoris using the linear ROI before and after walks (p < 0.0001). The overall (left and right limbs pooled) standard deviation of point selected values were greater than LN selected values of the biceps femoris (1.35 and 1.11) and gastrocnemius (1.51 and 1.23). In contrast, standard deviation for the gracilis measurements were decreased using point selection vs. LN selection (1.09 and 1.3). Conclusions: The biceps femoris and gracilis muscles demonstrated significant increases in surface temperature after 6 min of walking using the linear method of ROI. Measurement of numerous points along the entire length of the biceps femoris and gastrocnemius muscles may provide a more accurate assessment of the increased vascularity within the tissues resulting from work compared to single point selection. Clinical Significance: Prior activity and ROI selection method should be considered when interpreting thermography results.

Evaluation of serum 25-hydroxyvitamin D concentrations in a heterogeneous canine ICU population.

OBJECTIVE: To identify the prevalence of low serum 25-hydroxyvitamin D (25-OH-D) concentrations in critically ill dogs and determine whether vitamin D concentration measured at admission correlates with illness severity and patient outcome. DESIGN: Prospective observational study from December 2013 to July 2014. SETTING: Private referral teaching hospital ICU. ANIMALS: One hundred eleven critically ill dogs admitted to the ICU, and 28 apparently healthy control dogs. INTERVENTIONS: Measurement of 25-OH-D concentration and assessment of physiological parameters required to calculate illness severity scores. MEASUREMENTS AND MAIN RESULTS: Blood was sampled to measure serum 25-OH-D concentration, point-of-care laboratory data (packed cell volume, total plasma protein, venous blood gas, electrolytes, plasma lactate, and blood glucose concentration), platelet count, and serum albumin within 12 hours of admission. Primary disease etiologies were determined. Mentation score, Acute Patient Physiologic and Laboratory Evaluation (APPLE) fast score, length of ICU hospitalization, and survival to discharge were recorded. Low serum 25-OH-D concentrations were detected in 25% (28/111) of the ICU cohort; 25-OH-D concentrations (median; IQR) (89.2; 26.3 ng/mL [222; 140.0 nmol/L]) were significantly lower in hospitalized dogs compared with the healthy cohort (127.5; 44.5 ng/mL [318; 111.0 nmol/L]) (P < 0.0001). Serum 25-OH-D concentrations had a weak positive correlation with albumin (r = 0.34, P = 0.0003), but not with any other blood analyte evaluated. Serum concentration of 25-OH-D was also weakly correlated with APPLEfast score (r = 0.31, P = 0.001). 25-OH-D concentrations (median; IQR) were significantly higher in ICU dogs that survived to discharge (95.5; 55 ng/mL [238; 137 nmol/L]) compared with nonsurvivors (60.0; 54 ng/mL [149; 135 nmol/L]; P < 0.001). CONCLUSIONS: Low serum 25-OH-D was recorded in one-quarter of critically ill dogs, and was significantly lower in nonsurvivors in comparison to survivors. There was weak correlation between serum 25-OH-D and illness severity. Further studies are required to clarify relationships between vitamin D status and outcome.

Short-, intermediate-, and long-term results for endoluminal stent placement in dogs with tracheal collapse.

OBJECTIVE To evaluate outcomes following endoluminal stent placement for treatment of tracheal collapse (TC) in dogs. DESIGN Retrospective case series with nested observational study. ANIMALS 75 dogs that underwent endoluminal placement of a self-expanding metallic stent to treat TC between September 2009 and August 2015. PROCEDURES Medical records were reviewed to collect data on dog characteristics, clinical signs, TC type, diagnostic test results, peri- and postoperative complications, and outcomes. Complication rates and survival times and rates were compared between various groups. RESULTS The 75 dogs received 119 stents (56% [42/75] received 1 stent and 44% [33/75] received ≥ 2 stents). Thirty-eight (51%) dogs had a malformation type of TC, and 37 (49%) had the traditional type. Ninety-three percent (70/75) of dogs survived to hospital discharge. Median survival time was 1,005 days. Improvement in goose-honking or raspy breathing (89% [42/47]) and dyspnea (84% [43/51]) was reported at final follow-up examination. Major complications requiring additional stent placement procedures occurred in 47% (33/70) of dogs over the follow-up period; stent fracture and tissue ingrowth were the most common types. Male dogs and younger dogs had a significantly longer survival time than other dogs. Mainstem bronchial collapse at the time of stent placement had no significant association with outcome. CONCLUSIONS AND CLINICAL RELEVANCE Endoluminal stent placement provided a high survival rate for dogs with TC, even those with severe clinical signs. This information, as well as the information on potential complications, should be useful for advising owners of affected dogs.

Evaluation of hepatic tumor portal perfusion using mesenteric angiography: A pilot study in 5 dogs.

BACKGROUND: Mesenteric angiography is a sensitive method for visualizing portal perfusion in the dog. OBJECTIVES: To evaluate hepatic portal perfusion in dogs with incompletely resectable hepatic tumors using mesenteric angiography. ANIMALS: Five client-owned dogs with incompletely resectable hepatic tumors evaluated with mesenteric angiography. METHODS: Retrospective case series. Electronic medical records at the Animal Medical Center were analyzed to identify dogs that underwent mesenteric portography to determine blood flow to nonresectable hepatic tumors and subsequently determine ideal routes for transarterial embolization, vascular stent placement, or both. The images obtained from mesenteric angiography were analyzed and compared to those obtained from computed tomography angiography. RESULTS: Portography was accomplished using direct mesenteric venography in 3 dogs with hepatocellular carcinoma (HCC), cranial mesenteric arteriography in 1 dog with hepatic adenoma or well-differentiated HCC, and via splenic arteriovenous fistula in 1 dog with diffuse hepatic hemangiosarcoma metastases. Mean pixel densities in areas of hepatic tumor growth identified statistically significant decreases in portal blood flow (P = .02) compared to normal hepatic parenchyma. CONCLUSIONS AND CLINICAL IMPORTANCE: Initial findings indicate that the blood supply to large and metastatic hepatic tumors in dogs may correlate with that in humans, such that the majority of the tumor blood supply arises from the hepatic artery and not the portal vein. Differences in blood supply between normal hepatic parenchyma and hepatic tumors might be exploited by developing selective tumor therapies such as arterial embolization or chemoembolization that largely spare normal liver tissue. Further investigation is warranted.

Histological and dermatoscopic description of sphynx cat skin.

BACKGROUND: Histological and hair coat abnormalities of the alopecic sphynx cat have not been described in detail. The hairless allele (hr) in sphynx cats represents a mutation in the gene for keratin 71, a protein expressed in the inner root sheath of humans and mice. HYPOTHESIS/OBJECTIVES: To describe the histological and dermatoscopic abnormalities of sphynx cat skin. ANIMALS: Skin biopsies were collected from 14 sphynx cats and five cats with normal coats. Dermatoscopic examinations were performed on 11 sphynx cats and six additional control cats. METHODS: Vertical and horizontal sections of skin biopsy samples from sphynx and control cats were reviewed. Dermatoscopic images were compared between sphynx and control cats. RESULTS: Sphynx cat hair follicles were often small, curved and kinked and demonstrated infundibular hyperkeratosis and dilatation. Changes in the inner root sheath of sphynx cats included a poorly defined Henle's layer in addition to vacuolar-like changes and eosinophilic globules in Huxley's layer. Dermal papillae in sphynx cat anagen bulbs lacked the normal flame shape and were surrounded by epithelial cells arranged in a disorderly manner. The degree of follicular abnormalities varied between follicles. Follicular density was similar for both sphynx cats and control animals. Sphynx cat hair shafts were misshapen, smaller in diameter and rarely medullated. Dermatoscopy revealed similar hair coat density in sphynx and control cats. CONCLUSIONS AND CLINICAL IMPORTANCE: Sphynx cats demonstrated hair follicle dysplasia, with abnormal shaft production but without a decrease in follicle quantity. Abnormalities in sphynx cat follicles are similar to those in murine KRT71 mutants and suggest abnormal hair shaft keratinization.