Evaluation of ifosfamide salvage therapy for metastatic canine osteosarcoma

A retrospective study was performed to assess toxicity and response rate of ifosfamide salvage treatment for dogs diagnosed with metastatic osteosarcoma (OSA). Dogs diagnosed with OSA and previously treated with standard chemotherapy were included in the study. Nineteen dogs met the inclusion criteria, and 17 dogs were evaluable for response. Ifosfamide doses ranged from 375 to 425 mg m^?2 (median dose 375 mg m^?2), with a median of two doses administered per dog (range 1–7 doses). The overall response to ifosfamide was 11.8% [complete response (CR) = 1/17, partial response (PR) = 1/17, stable disease (SD) = 2/17, progressive disease (PD) = 13/17]. Two dogs were hospitalized due to ifosfamide toxicosis. The median survival duration from the first dose of ifosfamide to death was 95 days. Ifosfamide was well tolerated, but minor anti‐tumour activity was observed.     

VALIDATION OF AN INDEXED RADIOTHERAPY HEAD POSITIONING DEVICE FOR USE IN DOGS AND CATS

Setup variability affects the appropriate delivery of radiation and informs the setup margin required to treat radiation patients. Twenty‐four veterinary patients with head and neck cancers were enrolled in this prospective, cross‐sectional study to determine the accuracy of an indexed board immobilization device for positioning. Couch position values were defined at the first treatment based on setup films. At subsequent treatments, patients were moved to the previously defined couch location, orthogonal films were acquired, table position was modified, and displacement was recorded. The mean systematic displacement, random displacement, overall displacement, and mean displacement values of the three‐dimensional (3D) vector were calculated. Three hundred thirty‐two pairs of orthogonal setup films were analyzed for displacement in cranial–caudal, lateral, and dorsal–ventral directions. The mean systematic displacements were 0.5, 0.8, and 0.5 mm, respectively. The mean random displacements were 1.0, 1.1, and 0.7 mm, respectively. The overall displacements were 1.1, 1.4, and 0.9 mm, respectively. The mean 3D vector value was 1.6 mm with a standard deviation of 1.2 mm. Ninety‐five percent of the vectors were <3.6 mm. These values were compared to data obtained with a previously used immobilization device. A t‐test was used to compare the two devices. The 3D vector, random displacement in all directions, and overall displacement in the cranial–caudal and dorsal–ventral directions were significantly smaller than displacements with the previous device. The precision and accuracy of the indexed board device was superior to the historical head and neck device.     

Evaluation of a 15‐week CHOP protocol for the treatment of canine multicentric lymphoma

Dose intense CHOP protocols have been shown to improve outcome for people with non‐Hodgkin's lymphoma, but evaluation of dose intense CHOP protocols for canine lymphoma is currently limited. The hypothesis of this retrospective study was that a 15‐week dose intense CHOP protocol would have shorter treatment duration with similar efficacy to other doxorubicin‐based multidrug protocols. Thirty‐one client owned dogs with multicentric lymphoma were treated with a 15‐week CHOP chemotherapy protocol with an overall response rate of 100% and a median progression‐free interval (PFI) of 140 days [95% confidence interval (CI) 91–335 days]. Dogs that had two or more treatment delays had significantly prolonged PFI and overall survival in multivariate analysis. Dose intensity did not correlate with patient outcome. Dogs experiencing multiple treatment delays secondary to adverse events may receive their individual maximally tolerated dose while dogs with no adverse events may be underdosed. Future studies should focus on individual patient dose optimization.     

THE EFFECT OF DORSAL VERSUS VENTRAL RECUMBENCY ON THE RADIOGRAPHIC APPEARANCE OF THE CANINE THORAX

The thorax of nine dogs was radiographed with a vertical beam in both dorsal (VD) and ventral (DV) recumbency. The radiographs were evaluated subjectively and objectively for differences in appearance. To help explain appearance differences, lateral thoracic radiographs were made with the dogs in dorsal and ventral recumbency using a horizontally (laterally) directed x-ray beam. The appearance of thoracic viscera in VD and DV vertical beam radiographs differed. In VD vertical beam radiographs the craniocaudal axis of the heart appeared longer, the heart had a more consistent positional relationship to the thoracic spine, a larger area of the accessory lung lobe was visible, and a greater length of the caudal vena cava was visible. In DV radiographs the caudal lobar pulmonary arteries were more easily identified. The selection of dorsal versus ventral recumbency for thoracic radiography should be based on the clinical status of the patient and the reason(s) for which the radiograph is being made.     

A randomized controlled study into the efficacy and toxicity of pegylated liposome encapsulated doxorubicin as an adjuvant therapy in dogs with splenic haemangiosarcoma

Safety and efficacy of pegylated liposome encapsulated doxorubicin (PL‐DOX) was compared with free doxorubicin as an adjuvant monotherapy in dogs with splenic haemangiosarcoma after splenectomy in a randomized prospective clinical trial. A total of 17 dogs in each group were treated. No significant difference in survival between the two treatments was found. The calculated median overall survival time for the 34 dogs was 166 days [95% confidence interval (CI) 148–184]. The ½ year and one‐year survival was 41.2% (95% CI 24.8–56.9) and 22.7% (95% CI 9.9–37.4), respectively. In dogs treated with PL‐DOX, a desquamating dermatitis like palmar‐plantar erythrodysesthesia (PPES) was seen in two dogs, while three other dogs showed anaphylactic reactions. Cardiotoxicity was not seen in either treatment groups.     

Use of adjuvant carboplatin for treatment of dogs with oral malignant melanoma following surgical excision

Melanoma is the most common oral malignancy in dogs. This retrospective study evaluated adjuvant carboplatin chemotherapy (with or without radiation therapy) in 17 dogs with malignant oral melanoma following surgical resection. The median dosage and number of doses of carboplatin administered to the 17 dogs was 300 mg m^?2 (range, 150–300 mg m^?2) and 4 (range, 2–11), respectively. The overall median progression‐free survival for all dogs was 259 days [95% confidence interval (CI₉₅), 119–399 days]. The first progression‐free survival event was local recurrence in seven dogs (41%) and metastases in seven dogs (41%). The median overall survival for all dogs was 440 days (CI₉₅, 247–633 days). The tumour was the cause of death in 10 dogs (59%). On the basis of this study, systemic therapy with carboplatin may be an appropriate adjunct to local treatment for canine malignant melanoma, although future prospective controlled studies are needed to compare treatment modalities for this aggressive neoplasia.     

Use of a pulsed electromagnetic field for treatment of post-operative pain in dogs: a pilot study

Objective To determine if pulsed electromagnetic field (PEMF) therapy reduces post‐operative pain in dogs following ovariohysterectomy, and to evaluate PEMF interaction with post‐operative morphine analgesia. Study design Randomized controlled clinical trail. Animals Sixteen healthy dogs weighing 18 (10–32) kg [median (range)] and aged 13 (3–36) months. Materials and methods Anesthesia consisted of atropine (0.04 mg kg^?1, SC), acepromazine (0.02 mg kg^?1, SC), fentanyl (0.01 mg kg^?1, SC), thiopental (10–15 mg kg^?1, IV) and halothane in oxygen. Ovariohysterectomies were performed by senior veterinary students. Pain score (numeric rating scale, 0–28), pulse rate, respiratory rate, indirect mean arterial pressure (MAP), and body temperature were evaluated prior to anesthetic premedication, at extubation, 30 minutes after extubation, and then hourly for 6 hours. Following extubation, dogs were randomly divided into four groups: a control group that received 0.9% NaCl, IV, and no PEMF; a magnet group that received 0.9% NaCl, IV, and PEMF; a morphine group that received morphine 0.25 mg kg^?1, IV, and no PEMF; and, a magnet/morphine group that received morphine 0.25 mg kg^?1, IV, and PEMF. A single observer, blinded to treatment, obtained all behavioral observations and physiologic data. Data were analyzed using the Kruskal–Wallis statistical test with a significance of p < 0.05. Results Significant differences in MAP (mm Hg) [median (range)] occurred at 300 minutes [morphine 108 (83–114) and magnet/morphine 90 (83–97) < magnet 135 (113–117)], and at 360 minutes [magnet/morphine 93 (81–100) < control 127 (111–129) and magnet 126 (111–129)]. At 30 minutes the total pain score for the magnet/morphine group [1.5 (0–5)] was significantly less than control [8 (6–13)], but not different from magnet [5.5 (4–7)] or morphine [4.5 (2–9)]. Conclusions and clinical relevance Although no clear benefit was seen in this study, the results suggest that PEMF may augment morphine analgesia following ovariohysterectomy in dogs, and that further study of the analgesic effects of PEMF is warranted.     

MAGNETIC RESONANCE IMAGING CONTRAST ENHANCEMENT OF EXTRA‐OCULAR MUSCLES IN DOGS WITH NO CLINICAL EVIDENCE OF ORBITAL DISEASE

Enhancement of extra‐ocular muscles has been reported in cases of orbital pathology in both veterinary and medical magnetic resonance imaging. We have also observed this finding in the absence of orbital disease. The purpose of this retrospective study was to describe extra‐ocular muscle contrast enhancement characteristics in a group of dogs with no known orbital disease. Magnetic resonance images (MRI) from dogs with no clinical evidence of orbital disease and a reportedly normal MRI study were retrieved and reviewed. Contrast enhancement percentages of the medial, lateral, ventral, and dorsal rectus muscles were calculated based on signal‐to‐noise ratios that were in turn determined from hand‐traced regions of interest in precontrast, immediate postcontrast and 10‐min postcontrast scans. Comparison measurements were made in the pterygoid muscle. Contrast enhancement of the extra‐ocular muscles was observed in all patients (median contrast enhancement percentage 45.0%) and was greater than that of pterygoid muscle (median contrast enhancement percentage 22.7%). Enhancement of the extra‐ocular muscles persisted 10 min after contrast administration (median contrast enhancement percentage 43.4%). Findings indicated that MRI contrast enhancement of extra‐ocular muscles is likely normal in dogs.     

Hypofractionated radiation therapy in the treatment of canine thymoma: Retrospective study of eight cases

Thymomas are one of the most common tumors of the cranial mediastinum in dogs; however there is limited information available on the use of radiation therapy for treating this neoplasm. Objectives of the current retrospective observational study were to describe outcomes and side effects of a hypofractionated radiation therapy protocol in a group of dogs with confirmed thymoma. A total of eight dogs were included. To generate individualized treatment plans, we designed the planning target volume according to the limits on mean lung dose and the percentage of the total lung volume exceeding 20 Gy (V20). The total administered dose was 48–49 Gy, with one fraction per week for a total of six to seven fractions. After therapy, two dogs achieved complete responses, two achieved partial responses, and the disease remained stable in two. Two dogs died during the radiation therapy protocol and were not classified. The median mean lung dose and V20 were 6.0 Gy (range: 3.1–15.0 Gy) and 12.4% (range: 2.3–27.5%), respectively. The overall response rate was 50.0%, and the median time to response following treatment initiation was 22 days (range: 14–115 days). Acute and late side effects were common in the skin and/or lung and were self‐limiting or asymptomatic. The median survival time was not reached (range: 8–1128 days) and the 1 year survival rate was 75.0%. Hypofractionated radiation therapy was well tolerated in this sample of dogs with thymoma and may be considered when owners decline surgical treatment or the tumor is deemed unresectable.     

The pharmacokinetics of mavacoxib,a long‐acting COX‐2 inhibitor,in young adult laboratory dogs

Cox, S.R., Lesman, S.P., Boucher, J.F., Krautmann, M.J., Hummel, B.D., Savides, M., Marsh, S., Fielder, A., Stegemann, M.R. The pharmacokinetics of mavacoxib, a long‐acting COX‐2 inhibitor, in young adult laboratory dogs. J. vet. Pharmacol. Therap. 33 , 461–470. The pharmacokinetics of mavacoxib were evaluated in an absolute bioavailability study, a dose‐proportionality study and a multi‐dose study in young healthy adult laboratory Beagle dogs and in a multi‐dose safety study in Beagle‐sized laboratory Mongrel dogs. When administered as the commercial tablet formulation at 4 mg/kg body weight (bw) to fasted dogs, the absolute bioavailability (F) of mavacoxib was 46.1%; F increased to 87.4% when mavacoxib was administered with food. Following intravenous administration, the total body plasma clearance of mavacoxib was 2.7 mL·h/kg, and the apparent volume of distribution at steady‐state was 1.6 L/kg. The plasma protein binding of mavacoxib was approximately 98% in various in vitro and ex vivo studies. The dose‐normalized area under the plasma concentration–time curve was similar in Beagle and Beagle‐sized Mongrel dogs when mavacoxib was administered with food. Mavacoxib exhibited dose‐proportional pharmacokinetics for single oral doses of 2–12 mg/kg in Beagle dogs and for multiple oral doses of 5–25 mg/kg in Beagle‐sized Mongrel dogs. Only minor accumulation occurred when mavacoxib was administered at doses of 2–25 mg/kg bw orally to laboratory dogs with a 2‐week interval between the 1st two doses but with a monthly interval thereafter. Across all three Beagle studies (n = 63) the median terminal elimination half‐life (t_½) was 16.6 days, with individual values ranging 7.9–38.8 days. The prolonged t_½ for mavacoxib supports the approved regimen in which doses are separated by 2–4 weeks.     

Mechlorethamine,vincristine, melphalan and prednisone (MOMP) for the treatment of relapsed lymphoma in dogs

Eighty‐eight dogs with relapsed lymphoma were treated with the MOMP (mechlorethamine, vincristine, melphalan and prednisone) protocol on a 28‐day treatment cycle. The overall response rate (ORR) to the MOMP protocol was 51.1% for a median of 56 days (range 7–858 days). Twelve percent of dogs experienced a complete response for a median of 81 days (range 42–274 days) and 38.6% experienced a partial response for a median of 49 days (range 7–858 days). Dogs with T‐cell lymphoma had an ORR of 55% for a median of 60 days (range 49–858 days) while those with B‐cell lymphoma had an ORR of 57% for a median of 81 days (range 7–274 days) (P = 0.783). The overall survival time for all dogs was 183 days (range 17–974 days). Fifty‐four percent of dogs experienced toxicity with the majority classified as grade I. The MOMP protocol seems well‐tolerated and is an option for dogs with relapsed lymphoma.     

Potential risks,prognostic indicators,and diagnostic and treatment modalities affecting survival in dogs with presumptive aspiration pneumonia: 125 cases (2005–2008)

Objective – To evaluate a clinical population of dogs diagnosed with presumptive aspiration pneumonia (AP) and determine diagnostic and treatment modalities contributing to survival. Design – Retrospective study. Setting – A university veterinary teaching hospital in an urban setting. Animals – One hundred and twenty‐five dogs with presumed AP treated from 2005 to 2008. Interventions – None. Measurements and Main Results – Dogs with presumptive AP identified by a review of medical records had an overall survival of 81.6% (102/125). Male large‐breed dogs (mean 24.9 kg; 82/125) were overrepresented and were more likely to develop AP in this study population. Recent anesthesia had been performed in 16% (20/125), and vomiting was reported in 64% (80/125). The most common radiographic findings were a predominantly alveolar pattern (187/272, [68.8%] total lung lobes) in the right middle lung lobe (80/115, [69.6%]). A mean of 2 lung lobes were involved radiographically, and the relationship between survival and the number of lung lobes affected was statistically significant (P=0.04). Neutrophilia with a left shift was common with no significant change on consecutive daily evaluations. The mean PaO₂ was 77.7 mm Hg (SD, 17.5 mm Hg) (range, 40.7–100 mm Hg) with a median alveolar‐arterial gradient of 41.1 mm Hg (range, 8.1–81.8 mm Hg). In this study population, 37.6% (47/125) of dogs had microbial cultures performed and of these, 76.6% (36/47) were positive for growth; Escherichia coli (38.8%), Mycoplasma spp. (21.3%), Pasturella spp. (19.1%), and Staphylococcus spp. (17%) were the most common isolates in either single or multiagent infections. No treatment modality was statistically associated with increased survival. Colloid therapy was a negative prognostic indicator. Conclusions – In this study the overall prognosis for AP was good. Patients with only 1 affected lung lobe appeared more likely to survive. Supportive treatment modalities are warranted for the hospitalized patient, although no individual treatment method was found to be clearly superior to others.     

Phase II, open-label trial of single-agent CCNU in dogs with previously untreated histiocytic sarcoma

Background: Histiocytic sarcoma (HS) is an aggressive neoplasm in dogs, and in most instances, the disease is localized, but not amenable to surgical removal, or is disseminated. Affected patients usually die within 6 months. There have been no prospective studies to determine efficacy of single‐agent chemotherapy in dogs with HS. Hypothesis: Single‐agent CCNU [1‐(2‐chloroethyl)3‐cyclohexyl‐1‐nitrosourea; lomustine] has antitumor activity against HS in dogs. Animals: Twenty‐one dogs with histologically confirmed, nonresectable localized or disseminated HS. Methods: Prospective, open‐label phase II clinical trial in which dogs with previously untreated HS were uniformly treated with CCNU as a single oral dosage of 90 mg/m² every 4 weeks. The primary outcome measure was reduction in tumor size. Results: Fourteen dogs with disseminated HS and 7 with localized HS were enrolled between 1999 and 2008. Overall response rate was 29% (95% confidence interval [CI], 14–50%) for a median of 96 days (95% CI, 55–137 days). Three dogs (1 disseminated, 2 localized) had complete responses lasting for 54–269 days and 3 dogs (2 disseminated, 1 localized) had partial responses lasting for 78–112 days. Conclusions and Clinical Importance: CCNU, when used as a single agent, has activity against HS in dogs. Evaluation of CCNU postoperatively for dogs with resectable localized HS and as part of combination therapy for tumors that are nonresectable or disseminated should be considered.     

ASSESSMENT OF RESPIRATION‐INDUCED DISPLACEMENT OF CANINE ABDOMINAL ORGANS IN DORSAL AND VENTRAL RECUMBENCY USING MULTISLICE COMPUTED TOMOGRAPHY

Respiratory‐induced organ displacement during image acquisition can produce motion artifacts and variation in spatial localization of an organ in diagnostic computed tomography (CT) examinations. The purpose of this prospective study was to quantify respiratory‐induced abdominal organ displacement in dorsal and ventral recumbency using five normal dogs. All dogs underwent CT examinations using 64 multidetector row CT (64‐MDCT). A “3‐dimensional (3D) apneic CT exam” of the abdomen was acquired followed by a “4‐dimensional (4D) ventilated CT exam.” The liver, pancreas, both kidneys, both medial iliac lymph nodes, and urinary bladder were delineated on the 3D‐apneic examination and the organ outlines were compared to the maximum alteration in organ position in the 4D‐ventilated examination. Displacement was measured in dorsal‐to‐ventral (DV), right‐to‐left (RL), and cranial‐to‐caudal (CC) directions. Respiratory‐induced displacement of canine abdominal organs was not predictable and showed large variability in the three directions evaluated. For most canine abdominal organs, dorsal recumbency provided overall the least amount of displacement among all directions evaluated except for liver and urinary bladder. For liver, a large variability was found for all directions and a statistically significant difference was found only in the RL direction with ventral recumbency exhibiting less displacement (P = 0.0099). For the urinary bladder, ventral recumbency also provided less displacement but this was statistically significant only in the RL direction (P < 0.0001). Findings from this study indicated that dorsal recumbency may be preferred for minimizing respiratory motion artifacts in whole abdomen studies, but ventral recumbency may be preferred for liver and urinary bladder studies when respiration cannot be controlled.     

The Elekta Fraxion™ system is not suitable for maxillary fixation in canine conformal radiation therapy techniques

In this prospective, exploratory study, we evaluated the positioning accuracy in a group of 15 dogs undergoing fractionated stereotactic radiotherapy for tumors affecting the head, using a modified human maxillary fixation device (Elekta Fraxion? system). Positioning was assessed using on‐board volumetric imaging, with a six‐degrees‐of‐freedom image registration technique. Prior to treatment delivery, CBCT images were obtained and patient alignment was corrected, in both translational and rotational planes, using a six‐degrees‐of‐freedom robotic patient positioning system (HexaPOD Evo RT System). The maximum angular inter‐fraction motions observed were 6.1° (yaw), 10.9° (pitch), and 4.5° (roll). The mean systematic translational errors were 4.7, 2.6, and 2.3 mm, mean random translational errors were 3.0, 2.2, and 2.5 mm, and mean overall translational errors were 2.4, 0.7, and 2.3 mm in the cranial‐caudal, lateral, and dorsal‐ventral directions, respectively. The mean systematic rotational errors were 1.17°, 0.77°, and 1.43°, the mean rotational random errors were 1.65°, 1.46°, and 1.34° and the mean overall rotational errors were 0.56°, 0.22°, and 0.29° in the yaw, pitch, and roll directions, respectively. The mean error of the three‐dimensional vector was 6.9 mm with a standard deviation of 3.8 mm. Ninety‐five percent of the three‐dimensional vectors were <14.8 mm. This study demonstrates that this maxillary fixation device relies on six‐degrees‐of‐freedom registration and an ability to apply corrections using a six‐degrees‐of‐freedom couch for accurate patient positioning and tumor targeting. Its use in conformal radiation therapy in dogs is not recommended.     

Effect of antivenin dose on outcome from crotalid envenomation: 218 dogs (1988–2006)

Objective – To determine whether the dose of antivenin administered is associated with a difference in survival of crotalid‐envenomated dogs. A secondary objective was to determine whether other covariables affect survival. Design – Retrospective study (1988–2006). Setting – Private referral center and university small animal teaching hospital. Animals – Two hundred and eighteen dogs with evidence of crotalid envenomation and treatment with equine‐derived antivenin. Interventions – Administration of antivenin. Measurements and Main Results – Patient signalment, physical and clinicopathologic data at time of presentation, treatments, complications of antivenin therapy, length and cost of hospitalization, and outcome were recorded. Confidence intervals were determined for the difference in median number of vials administered and for median dosage for patients that lived versus died. Penalized logistic regression was performed to evaluate the effect of other covariables on survival. The median age of affected dogs was 3 years (range 6 w–12 y) with a median weight of 25.7 kg (range 1.95–86.4 kg). The median number of antivenin vials administered was 1.0 (range 1.0–10.0). Acute and chronic reactions were reported in 7% (16/218) and 0.9% (2/218) of dogs, respectively. Nine of 218 dogs (4.1%) died. The median number of vials administered to the nonsurvivors and survivors were 2.0 (range 1–5 vials) and 1.0 (range 1–10 vials), respectively. The median number of vials received was significantly different in dogs that died versus those that lived (P<0.05). Increased heart rate (P=0.02) and petechiation (P=0.04) were associated with decreased likelihood of survival, while diphenhydramine (P=0.02) and fluoroquinolone (P=0.046) administration was associated with increased likelihood of survival. The median duration of hospitalization was 1.0 day (range 2 h–22 d). The median cost of hospitalization was US$1592.00 (range US$267.20–US$6738.00). Conclusion – The administration of more vials of antivenin is potentially associated with negative outcome; however, a causal relationship has not been established. Controlled, prospective studies are needed to optimize antivenin administration.     

Comparison of two insulin protocols for diabetic dogs undergoing cataract surgery

Objective To evaluate the effectiveness of two insulin doses to maintain an acceptable range of blood glucose concentrations (70–200 mg dL^?1) in the peri‐operative period in diabetic dogs. Animals Twenty‐four diabetic dogs with a median weight of 20.6 kg and a median age of 8 years old. Methods The dogs were randomly assigned to receive either 25 or 100% of their normal insulin dose subcutaneously on the morning of surgery. The anesthetic and feeding protocols were standardized. On the day before surgery, venous blood was collected for measurement of β‐hydroxybutyrate, cholesterol, glucose, glycosylated hemoglobin, hematocrit, total plasma protein and urea nitrogen. On the day of surgery, blood glucose concentrations were measured prior to anesthesia, prior to the start of surgery, 1 and 2 hours after beginning of surgery, 1 hour after extubation, at 16 : 00 hours and at 20 : 00 hours. β‐hydroxybutyrate concentrations were measured at 20 : 00 hours that day. At 08 : 00 hours the following day, β‐hydroxybutyrate and glucose concentrations were measured. The significance of differences between groups was tested with Wilcoxon's two‐tailed rank‐sum test, Chi‐square test and Fisher's exact test. Results There were no differences in insulin treatments, clinical signs, concurrent diseases and most clinicopathological parameters between the two groups of dogs at entry to the study. The 25% dose group had blood glucose values of 296 (102–601) mg dL^?1 at 16 : 00 hours and 429 (97–595) mg dL^?1 at 20 : 00 hours on the day of surgery. The 100% insulin dose group had lower corresponding values of 130 (55–375) mg dL^?1 (p = 0.04) and 185 (51–440) mg dL^?1 (p = 0.004). No other differences (p < 0.05) were detected between the two groups. Conclusions The administration of a full dose of insulin is only marginally advantageous for reducing glucose to normal (70–120 mg dL^?1) after anesthesia but neither dose consistently induced glycemic values in an acceptable range (70–200 mg dL^?1) or normoketonemia. Clinical relevance Blood glucose should be measured immediately before anesthesia and periodically throughout the peri‐operative period in all diabetic dogs because presurgical subcutaneous administration of 25 or 100% of the normal insulin dose resulted in unpredictable blood glucose concentrations.     

FEASIBILITY OF PERCUTANEOUS CONTRAST ULTRASOUND‐GUIDED CHOLECYSTOGRAPHY IN DOGS

Differentiating hepatocellular disease versus biliary obstruction can be challenging in dogs presented for icterus. The purpose of this prospective study was to determine the feasibility of percutaneous contrast ultrasound‐guided cholecystography in dogs. Ten normal dogs weighing 7.6–13.0 kg (median 9.8 kg) were recruited. All dogs were considered normal based on complete blood count, serum chemistry profile, ultrasound examination, and percutaneous radiographic cholecystography. Percutaneous contrast ultrasound‐guided cholecystography was performed using 0.5 ml of commercially available contrast agent and two conventional ultrasound machines for simultaneous scanning at two different locations. Two observers independently evaluated the time to initial detection of contrast in the proximal duodenum and duration of contrast enhancement via visual monitoring. Dynamic contrast enhancement was calculated using time‐intensity curves. Mean (±SD) and median (range) of time to initial detection were 8.60 s (± 3.35) and 8.0 s (2.0–11.0), respectively, and mean and median duration were 50.45 s (±23.24) and 53.0 s (20.0 – 70.0), respectively. Mean, median, and range of peak intensity were 114.1 mean pixel value (MPV) (SD ± 30.7), 109.2 MPV, and 79.7–166.7, respectively, and mean, median, and range of time to peak intensity were 26.1 s (SD ± 7.1 s), 24.0 s, and 19.0–41.0 s, respectively. Findings indicated that percutaneous contrast ultrasound‐guided cholecystography is a feasible technique for detecting and quantifying patency of the bile duct in normal dogs. Future studies are needed to assess the diagnostic utility of this technique for dogs with biliary obstruction.