Objective—To evaluate the stability and retention of viscous formulations of the antifungal drug clotrimazole in vitro and to evaluate retention times, absorption, and histologic response to these compounds when placed in the frontal sinus of dogs.
Animals—6 male Beagles.
Procedures—1% clotrimazole gels were formulated with hydroxypropyl cellulose, poloxamer, and carboxymethylcellulose sodium bases. Commercially available 1% clotrimazole creams were also evaluated. Each compound was incubated at 37°C in a funnel. Volume retained and clotrimazole stability were evaluated for 4 weeks. Six compounds were then chosen for in vivo evaluation. The frontal sinuses of 6 dogs were filled with 1 of the 6 compounds. Computed tomographic evaluation was performed weekly for up to 4 weeks to evaluate gel retention. Blood samples were collected to evaluate clotrimazole absorption. Following euthanasia, sinuses were examined histologically.
Results—Commercially available clotrimazole creams were not retained in funnels in vitro. In vivo, hydroxypropyl cellulose– and carboxymethylcellulose-based gels resulted in the most severe inflammatory response and were retained the longest. Poloxamer-based gels had a shorter retention time and were associated with less inflammation. Clotrimazole was minimally absorbed. Despite a marked inflammatory response to several of the clotrimazole-containing gels, no notable adverse clinical responses were observed.
Conclusions and Clinical Relevance—Poloxamer gels had the most promise for improving drug contact within the frontal sinus of dogs, while limiting the inflammatory response. Poloxamer gels have the additional benefit of improved handling as a result of reverse gelation (ie, they gel when warmed to 37°C).
Objective—To evaluate the effects of fascial abrasion, fasciotomy, and fascial excision on cutaneous wound healing in cats.
Animals—Eight 1- to 3-year-old domestic shorthair cats.
Procedures—8 evenly spaced 4-cm2 skin wounds were created on each cat's dorsum, and the underlying subcutaneous tissue was removed to expose the epaxial muscle fascia. Wounds were randomized to receive 1 of 4 treatments (2 wounds/treatment/cat): fascial abrasion, fasciotomy, fascial excision, or control treatment (muscle fascia not disturbed). Bandages were changed and digital photographs and acetate tracings of the wounds were obtained for planimetry daily for 1 week, every other day for 2 weeks, and then every third day for 3 weeks (ie, 40-day observation period). Digitized images were evaluated for granulation tissue formation, wound contraction (surface area measurements), and area of epithelialization.
Results—The epithelialized area and open and total wound areas did not differ among treatments at any time point. Time to the first appearance of granulation tissue was significantly shorter for all treatment groups, compared with that of the control group. Time to achieve granulation tissue coverage of wound base was significantly shorter following fasciotomy (9.6 days) and fascial excision (9.0 days), compared with that of control treatment (18.5 days) or abrasion (16.7 days). Numbers of wounds that developed exuberant granulation tissue following fascial excision (9/16) and control treatment (3/16) differed significantly.
Conclusions and Clinical Relevance—Fasciotomy and fascial excision facilitated early granulation tissue development in cutaneous wounds in cats. In clinical use, these fascial treatments may expedite secondary wound closure or skin grafting.
OBJECTIVE To evaluate the 3-D geometry of canine pelves and to characterize the long-term effects of juvenile pubic symphysiodesis (JPS) on pelvic geometry by comparing the pelvic configuration between littermates that did and did not undergo the procedure.
ANIMALS 24 Labrador Retriever, Golden Retriever, or Labrador Retriever–Golden Retriever crossbred service dogs from 13 litters.
PROCEDURES At 16 weeks old, puppies with a hip joint distraction index ≥ 0.5 were randomly assigned to undergo thermal JPS (n = 9), mechanical JPS (7), or a sham (control) surgical procedure (8). Ten years later, each dog underwent a CT scan of the pelvic region. Modeling software was used to create 3-D reconstructions from the CT scans, and various pelvic measurements were made and compared among the 3 treatments.
RESULTS Compared with the control treatment, thermal and mechanical JPS increased the hemipelvis acetabular angle by 4°, the acetabular angle of lateral opening by 5°, and the orientation of the medial acetabular wall in a transverse plane by 6°, which indicated that JPS increased dorsal femoral head coverage by the acetabulum. Both JPS procedures decreased the pelvic canal area by approximately 20% and acetabular inclination by 6° but did not alter acetabular retroversion.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that thermal and mechanical JPS were equally effective in altering the 3-D pelvic geometry of dogs. These findings may help guide future studies of alternatives for optimizing canine pelvic anatomy to minimize the risk of hip dysplasia and associated osteoarthritis.
To determine whether muscle-sparing laryngoplasty results in fewer changes in swallowing function compared to standard surgical treatment for laryngeal paralysis.
12 clinically normal sexually intact male Beagles.
Group A dogs (n = 4) had a standard approach to the larynx, with left arytenoid cartilage lateralization. Group B dogs (n = 4) had a muscle-sparing laryngoplasty performed with the thyropharyngeus muscle fibers bluntly separated, and the cricoarytenoideus dorsalis muscle spared. Pre- and 24-hour postoperative fluoroscopic swallowing studies were performed and graded. Larynges were harvested after humane euthanasia, and glottic area was measured. Group C dogs (n = 4) acted as controls, with surgical dissection ending lateral to the thyropharyngeus muscle, arytenoid lateralization not performed, and the dogs not euthanized. The study was performed between October 15, 2011 and May 15, 2021.
Changes in pharyngeal and upper esophageal sphincter function were not detected in any group. There was no difference in glottic area between treatment groups. Aspiration of liquid was not a consistent finding. Two dogs in each treatment group developed moderate to severe cervical esophageal paresis. This did not occur in control dogs.
We found no evidence to support our hypothesis that muscle-sparing laryngoplasty results in less severe changes in swallowing function compared to a standard technique. The cervical esophageal paresis identified in both treatment groups could increase the risk of postoperative aspiration pneumonia in dogs treated for laryngeal paralysis via a lateral approach to the larynx. Further study to determine the frequency, cause, and duration of esophageal dysfunction is warranted.