Objective—To determine various measurements of medial retropharyngeal lymph nodes (MRPLNs) in healthy cats via ultrasonography and CT.
Animals—45 cats (age range, 2 to 8 years).
Procedures—Cats underwent CT of the head and ultrasonography of the cervical region. Various measurements of MRPLNs were obtained, and parenchymal heterogeneity, presence of a hilus, appearance of margins, and attenuation of MRPLNs were determined.
Results—Data for 7 cats were excluded because they did not meet inclusion criteria; data for 38 cats were evaluated. Measurements of left and right MRPLNs were not significantly different. Mean length × rostral height × rostral width dimensions of MRPLNs were 20.7 × 12.4 × 3.7 mm and 20.7 × 13.1 × 4.7 mm in ultrasonographic and CT images, respectively. Maximum MRPLN dimensions were approximately 32 × 20 × 7 mm. Mean attenuation of MRPLNs was 40.2 Hounsfield units. Parenchyma of MRPLNs was mildly (via CT) to moderately (via ultrasonography) heterogeneous. A hilus was identified in 95% (via ultrasonography) and 24% or 92% (via CT [depending on criteria used to define a hilus]) of MPRLNs. Lymph node margins were smooth in CT images and mildly irregular in ultrasonographic images. A negative linear correlation was detected between age of cat and MRPLN volume.
Conclusions and Clinical Relevance—MRPLNs in cats were easily imaged via ultrasonography and CT. Left and right MRPLNs were symmetric, and MRPLNs were larger in young adult cats versus old cats. Data were intended to serve as references for evaluation of MRPLNs in healthy cats.
Objective—To investigate differences in clinical variables among dogs with extrahepatic portosystemic shunts (EHPSSs) of various morphologies.
Design—Retrospective case series.
Animals—53 dogs with EHPSSs.
Procedures—Medical records of dogs undergoing preoperative CT angiography of an EHPSS over a 3-year period were reviewed. Analysis was performed to investigate relationships of clinical variables with shunt morphology. Morphologies were analyzed individually as well as in several groups.
Results—Shunt morphologies included 10 splenocaval, 9 splenophrenic, 11 splenoazygos, 10 right gastric-caval, 12 right gastric-caval with a caudal loop, and 1 right gastric-azygos with a caudal loop. Several biochemical variables associated with EHPSS were lowest in dogs with splenocaval shunts. Preoperative clinical signs were more common in dogs that had shunts with vena caval than right azygos vein insertion (36/41 [88%] vs 7/12 [58%]) and insertion caudal to the liver than diaphragmatic insertion (29/32 [91%] vs 14/21 [67%]). Neurologic signs were more common when shunts inserted into the vena cava caudal to the liver than in other locations (21/32 [66%] vs 6/21 [29%]) and were most frequent with splenocaval shunts. Urinary tract signs were more common when shunts had right gastric vein origin than gastrosplenic vein origin (14/23 [61%] vs 10/30 [33%]).
Conclusions and Clinical Relevance—Splenocaval shunts caused more clinical abnormalities than did other shunt morphologies. Results suggested that dogs with shunt insertion in the caudal vena cava, especially caudal to the liver, were most likely to have clinical signs.
A 5-year-old sexually intact female Alaskan Malamute was evaluated at the Veterinary Teaching Hospital at Michigan State University because of lethargy of 1 day's duration and a single episode of vomiting. The dog's most recent estrous cycle had occurred 8 months prior to hospital admission. The dog was successfully bred during this cycle, and healthy puppies were delivered via cesarean section.
On physical examination, the patient was hyperthermic with a rectal temperature of 40.1°C (104.2°F) and tachycardic with a heart rate of 132 beats/min. The abdomen was tense, and a mass (diameter, approx 10 cm) was palpated in the
A 2-year-old 5.2-kg (11.4-lb) spayed female domestic shorthair cat was evaluated because of acute dyspnea. One week prior to evaluation, the cat had a right forelimb lameness, the cause of which was unknown. The referring veterinarian performed radiography of the right forelimb; radiographic findings revealed a closed fracture of the distal aspect of the right ulna. The cat was placed under general anesthesia without endotracheal intubation for splint placement. No other injuries or abnormalities were found on physical examination. No signs of respiratory distress were apparent.
At the time of referral, the cat was open-mouth breathing. Orthopnea was evident.
A 14-year-old female spayed domestic longhair cat was evaluated because of progressive weight loss over 4 months and recent onset of tenesmus. A serum biochemical profile revealed high activities of alanine aminotransferase (247 U/L; reference range, 10 to 100 U/L) and alkaline phosphatase (128 U/L; reference range, 6 to 102 U/L). No abnormalities were detected on CBC or urinalysis. On physical examination, a large firm mass was palpated in the middle portion of the abdomen. Radiographs of the abdomen were obtained (Figure 1).
Left lateral (A), right lateral (B), and ventrodorsal (C) radiographic views of
Objective—To quantitatively and qualitatively assess the radiographic appearance of the thorax of clinically normal alpaca crias.
Animals—21 clinically normal alpaca crias.
Procedures—Left-right lateral (LR), right-left lateral (RL), dorsoventral (DV), and ventrodorsal (VD) projections of the thorax were acquired. To account for differences in cria size, measurements of thoracic structures were compared with other anatomic landmarks.
Results—Mean ± SD vertebral heart scale was 9.36 ± 0.65 for LR projections, 9.36 ± 0.59 for RL projections, 8.21 ± 0.51 for DV projections, and 8.65 ± 0.57 for VD projections. Dimensions of the heart were compared with the length of the T3 through T5 vertebral bodies, third to fifth rib distance, and thoracic height and width, which provided additional methods of cardiac evaluation. For RL projections, mean ratio of the right cranial pulmonary artery diameter to the third rib width was 0.41 ± 0.10 and mean ratio of the right cranial pulmonary vein to the third rib width was 0.44 ± 0.10. Caudal lobar pulmonary vessels and the caudal vena cava were difficult to quantitatively assess on DV or VD projections. On lateral projections, the trachea was increased in diameter at the origin of the right cranial lobar bronchus. No qualitative differences were found between LR and RL radiographs. The lungs were generally better inflated on VD projections, with more separation of the heart and diaphragm.
Conclusions and Clinical Relevance—Establishment of radiographic values for alpaca crias should prove useful in assessment of thoracic disease in this species.
To use CT-derived measurements to calculate a shape constant (K constant) and create a formula to calculate body surface area (BSA) on the basis of body weight in bearded dragons (Pogona vitticeps).
12 adult client-owned bearded dragons that underwent CT between December 4, 2019, and April 2, 2020.
Each bearded dragon in this prospective cohort study underwent physical examination, body weight measurement, and CT. A 3-D surface model was then reconstructed from CT data with available software and used for BSA calculations. Animals were considered collectively and grouped by sex and age. Nonlinear regression analysis of BSA versus body weight was performed, and a species-specific formula was derived for calculating BSA in bearded dragons.
Mean age, body weight, and CT-derived BSA were 2.1 years, 356 g, and 580 cm2. The calculated K constant was 11.6 (R2 = 0.994; SE = 0.275) for the 12 bearded dragons, and the CT-derived BSA formula was as follows: BSA in cm2 = 11.6 × (body weight in g)2/3. The K constant differed substantially for bearded dragons grouped by age (12.1 for younger [between 1 and ≤ 2 years of age; n = 8] vs 10.9 for older [> 2 years of age; 4] animals) but did not differ on the basis of sex.
CONCLUSIONS AND CLINICAL RELEVANCE
Results indicated that because the K constant for bearded dragons in the present study was larger than the preexisting K constant of 10 used for reptiles or the various K constants established for some companion mammals, doses of chemotherapeutic drugs needed to treat affected bearded dragons may be higher than previously thought.
To determine whether previously described cutoffs for ultrasonographically determined kidney length-to-aorta diameter ratio (KL:Ao) for evaluation of kidney size in adult dogs are applicable to healthy dogs 1 to 18 months of age and to assess interobserver and intraobserver variability for ultrasonographic kidney and aorta measurements in these dogs grouped according to age.
41 university-owned dogs and 41 client- or staff-owned dogs of 3 age groups (approx 1, 6, and 12 to 18 months of age) underwent ultrasonographic examination by 3 observers. Kidney length, kidney width, and diameter of the aorta were measured by each observer 3 times, and KL:Ao and kidney length-to-body weight ratio were calculated for each dog. Measurements and calculated ratios for the 3 age groups were compared by statistical methods; interobserver and intraobserver variability were calculated.
Mean kidney length, kidney width, and aorta diameter were smaller, and calculated KL:Ao and kidney length-to-body weight ratio were larger, for dogs of the 1-month age group than for dogs of the 6-month and 12 to 18–month age groups. There were significant interobserver differences for ultrasonographic measurements in all age groups; these were most frequent in the youngest group of dogs and affected KL:Ao for that group only.
CONCLUSIONS AND CLINICAL RELEVANCE
Results revealed that 1-month-old dogs have larger kidneys relative to body weight and aorta diameter than do older dogs. Interobserver variability for the youngest group of dogs indicated limited usefulness of these measurements and related ratios for neonatal dogs in clinical practice. The KL:Ao values for dogs ≥ 6 months of age in this study were similar to values previously described for dogs > 12 months of age.
Objective—To evaluate effects of commonly used anesthetics administered as single bolus injections on splenic volume.
Animals—10 adult Beagles.
Procedures—A randomized crossover study was conducted. Computed tomography was performed on dogs to determine baseline splenic volume and changes after IV injection of assigned drug treatments. Dogs were allowed to acclimate for 10 minutes in a plastic crate before acquisition of abdominal CT images. Treatments were administered at 7-day intervals and consisted of IV administration of saline (0.9% NaCl) solution (5 mL), acepromazine maleate (0.03 mg/kg), hydromorphone (0.1 mg/kg), and dexmedetomidine (0.005 mg/kg) to all 10 dogs; thiopental (8 mg/kg) to 5 of the dogs; and propofol (5 mg/kg) to the other 5 dogs. Splenic volume was calculated from the CT images with image processing software. A repeated-measures ANOVA was performed, followed by a Bonferroni post hoc test.
Results—No significant difference in splenic volume was detected between the acepromazine, propofol, and thiopental treatments, but splenic volume was greater with these drugs than with saline solution, hydromorphone, and dexmedetomidine. Splenic volume was less with hydromorphone, compared with dexmedetomidine, but splenic volume with hydromorphone and dexmedetomidine did not differ significantly from that with saline solution.
Conclusions and Clinical Relevance—Administration of acepromazine, thiopental, and propofol resulted in splenomegaly. Dexmedetomidine did not alter splenic volume. Hydromorphone slightly decreased splenic volume. Propofol should not be used when splenomegaly is not desirable, whereas hydromorphone and dexmedetomidine may be used when it is best to avoid splenic enlargement.
An 8-year-old 5-kg (11-lb) spayed female Miniature Dachshund was examined as part of a routine wellness and vaccination program. On physical examination, the dog was quiet, alert, and responsive; however, a large mass was palpated in the caudal aspect of the dog's abdomen. Results of CBC and serum biochemical analyses indicated high RBC count (9.54 × 106 RBCs/uL; reference range, 5.39 × 106 to 8.7 × 106 RBCs/uL), Hct (59%; reference range, 38.3% to 56.5%), and hemoglobin concentration (21.6 g/dL; reference range, 13.4 to 20.7 g/dL) and low blood glucose concentration (62 mg/dL;