Repeated bolus injections of bupivacaine for continuous bilateral transversus thoracis plane block undergoing median sternotomy in a dog: A case report.

An 8-year-old, 6.5 kg, neutered female Shih-Tzu dog was presented for surgical resection of a mediastinal mass. A median sternotomy and left cranial lung lobectomy were performed. Intraoperatively, with the patient under general anaesthesia, a bilateral transversus thoracis plane (TTP) block was performed by injecting 0.5% bupivacaine (0.2 ml/kg) per side using real-time ultrasound guidance. After surgery, indwelling catheters for repeated bolus injections of bupivacaine in TTP were placed as follows: the fifth sternebra was palpated in dorsal recumbency, and the transducer was placed in the longitudinal plane lateral to the sternal border. A 16 gauge over-the-needle catheter was inserted caudo-cranially using an in-plane technique and located in the TTP. An intermittent bolus of bupivacaine (0.1 ml/kg) per side was injected via the indwelling catheter every 8 h for 3 days, with a constant rate infusion of an intravenous fentanyl (1 µg/kg/h) and ketamine (0.12 mg/kg/h) combination. Post-operative pain was evaluated using the Glasgow composite measure pain scale and the score was 4-5/24 on the day of surgery and gradually decreased over time. Additional rescue analgesia was not required. Repeated boluses of bupivacaine for a continuous bilateral TTP block may be a useful adjuvant for perioperative pain management strategies, including median sternotomy, in dogs.

Epicutaneous Allergen Administration with Microneedles as a Novel Method of Immunotherapy for House Dust Mite (HDM) Allergic Rhinitis.

PURPOSE: Epicutaneous immunotherapy (EPIT) is being studied as a method for treating allergic rhinitis because of skin immunology, user convenience and enhanced patient compliance. However, the use of EPIT is limited because of the very low skin permeability of the allergen. In this study, the limitations of EPIT were overcome by using sophisticated delivery with microneedles. The immunological efficacy of this method was studied in a murine model of house dust mite (HDM) allergic rhinitis. METHODS: The length of the microneedles was 400 µm, and the coating formulation containing HDM was locally distributed near the end of the microneedle tips. The change of distribution of FITC-dextran in porcine skin in vitro was observed over time using a confocal microscope. The effect of immunotherapy in the allergic rhinitis model, sensitized by HDM-coated microneedles (HDM MNs), was observed according to the amount of HDM applied. RESULTS: The microneedles delivered the coating formulation with precision into the porcine skin layer, and the coated formulation on the microneedles was all dissolved in the porcine skin in vitro within 20 min of administration and then gradually diffused into the skin layer. When HDM MNs were administered to mice, a 0.1-µg dose of HDM provided the most effective immunization, and improved efficacy was shown between 0.1- and 0.5- µg doses of HDM. CONCLUSIONS: Effective immunotherapy can be achieved by precision delivery of the allergen into the skin layer, and microneedles can provide effective immunological therapy by delivering the appropriate amount of allergen.

Genetic Variants and Clinical Phenotypes in Korean Patients With Hereditary Hemorrhagic Telangiectasia.

OBJECTIVES: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant vascular disorder characterized by recurrent epistaxis, telangiectasia, and visceral arteriovenous malformations (AVMs). Activin A receptor-like type 1 (ACVRL1/ALK1) and endoglin (ENG) are the principal genes whose mutations cause HHT. No multicenter study has yet investigated correlations between genetic variations and clinical outcomes in Korean HHT patients. METHODS: Seventy-two members from 40 families suspected to have HHT based on symptoms were genetically screened for pathogenic variants of ACVRL1 and ENG. Patients with genetically diagnosed HHT were also evaluated. RESULTS: In the HHT genetic screening, 42 patients from 24 of the 40 families had genetic variants that met the pathogenic criteria (pathogenic very strong, pathogenic strong, pathogenic moderate, or pathogenic supporting) based on the American College of Medical Genetics and Genomics Standards and Guidelines for either ENG or ACVRL1: 26 from 12 families (50%) for ENG, and 16 from 12 families (50%) for ACVRL1. Diagnostic screening of 42 genetically positive HHT patients based on the Curaçao criteria revealed that 24 patients (57%) were classified as having definite HHT, 17 (41%) as having probable HHT, and 1 (2%) as unlikely to have HHT. Epistaxis was the most common clinical presentation (38/42, 90%), followed by visceral AVMs (24/42, 57%) and telangiectasia (21/42, 50%). Five patients (12%) did not have a family history of HHT clinical symptoms. CONCLUSION: Only approximately half of patients with ACVRL1 or ENG genetic variants could be clinically diagnosed as having definite HHT, suggesting that genetic screening is important to confirm the diagnosis.

Evaluation of the ureteral jet in dogs by using color Doppler ultrasonography.

Ureteral jets are the result of a forceful ejection of urine from the vesicoureteral junction into the urinary bladder. By using color Doppler ultrasonography (US), we aimed to identify distinct ureteral jets in dogs, provide insight into ureteral obstruction, and facilitate study of urodynamics and vesicoureteric sphincter function via pulsed Doppler US. Color Doppler US was applied to detect urinary flow from the right ureteral orifices in eight healthy beagles. Under anesthesia, 0.9% saline (2.5 mL/kg/h) and furosemide (0.5 mg/kg) were administered intravenously to assist in detection of distinct ureteral jets and examine their frequency, velocity, duration, and waveform. In all dogs, ureteral jets were visualized under diuresis and anesthesia within 2 to 5 min (mean 3.57 ± 0.90 min) of the furosemide injection. Mean frequency, peak velocity, and duration of right ureteral jets in seven dogs in whom six ureteral jet waveform patterns were identified were 9.86 ± 3.09 jets/min, 34.07 ± 10.02 cm/sec, and 2.82 ± 1.08 sec, respectively. During the 10 min period starting 10 min after the initial jet appeared, only three waveforms were identified. Color Doppler US of ureteral jets may aid in assessing vesicoureteric sphincter function and ureteral abnormalities, such as ureteral obstruction, in dogs.

Usefulness of CT imaging for segmental lung lobe torsion without typical radiographic imaging in a Pomeranian.

A 3-year-old, intact female Pomeranian presented with a 1-month history of coughing. Thoracic radiography showed focal infiltration of the left cranial lung lobe and widening of the cranial mediastinum. Subsequent computed tomography revealed torsion of the caudal segment of the left cranial lung lobe, which was confirmed by exploratory thoracotomy. There was no apparent underlying etiology for the condition. To the authors' knowledge, this is the first report of lung lobe torsion in this breed and the first detailed CT imaging report for segmental lung lobe torsion.

Nonsurgical resolution of caudal mediastinal paraesophageal abscess in a cat.

A one-year-old, castrated male domestic short hair cat was admitted with a history of anorexia, regurgitation and pyrexia for two days. Fever and leukocytosis were identified. There were a large soft tissue density oval mass in the caudal mediastinum on thoracic radiographs, a fluid-filled oval mass in the caudal mediastinum on ultrasonography, and left-sided and ventrally displaced and compressed esophagus on esophagram. On esophageal endoscopy, there were no esophageal abnormalities. CT findings with a fluid filled mass with rim enhancement indicated a caudal mediastinal paraesophageal abscess. The patient was treated with oral antibiotics, because the owner declined percutaneous drainage and surgery. The patient was admitted on emergency with severe respiratory distress; and ruptured abscess and deteriorated pleuropneumonia were suspected. With intensive hospitalization care and additional antibiotic therapy, the patient had full recovery.

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.

Comparison of echocardiography with dual-source computed tomography for assessment of left ventricular volume in healthy Beagles.

OBJECTIVE: To compare echocardiographic measurements of left ventricular (LV) volume obtained via a modified Simpson or Teichholz method with those obtained via dual-source CT (DSCT). ANIMALS: 7 healthy Beagles. PROCEDURES: Each dog was anesthetized for DSCT; LV volume was determined from contrast-enhanced images of the LV lumen during all phases of contraction. Echocardiography was performed with dogs awake and anesthetized. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume, and ejection fraction were measured via a modified Simpson method and Teichholz method. Each dog was anesthetized twice with a 1-week interval between anesthetic sessions. RESULTS: Results obtained while dogs were anesthetized revealed that the modified Simpson method underestimated LV volume (mean ± SD EDV, 24.82 ± 2.38 mL; ESV, 12.24 ± 1.77 mL), compared with that estimated by the Teichholz method (EDV, 32.57 ± 2.85 mL; ESV, 14.87 ± 2.09 mL) or DSCT (EDV, 34.14 ± 1.57 mL; ESV, 16.71 ± 0.76 mL). Ejection fraction (modified Simpson method, 48.53% ± 4.24%; Teichholz method, 54.33% ± 4.26%; DSCT, 51.00% ± 2.71%) differed significantly among the 3 methods. Echocardiographic results obtained while dogs were awake revealed that EDV, ESV, and stroke volume differed significantly between the modified Simpson and Teichholz methods. CONCLUSIONS AND CLINICAL RELEVANCE: LV volume determined via the Teichholz method was more similar to that determined via DSCT than was the LV volume determined via the modified Simpson method. The modified Simpson method underestimated LV volume, compared with that obtained via the Teichholz method, in both anesthetized and awake dogs.

Comparative study of cardiac anatomic measurements obtained by echocardiography and dual-source computed tomography.

The aim of this study was to verify the accuracy of echocardiography by dual-source computed tomography (DSCT). Seven normal beagles underwent DSCT and echocardiography. Echocardiographic measurements were obtained according to the American Society of Echocardiography guidelines. The DSCT images were reconstructed onto the same echocardiographic image plane by using a reconstruction program, and then anatomical measurements were obtained. Nonparametric analysis was used for verifying the significance of each of the measured parameters. The anatomical measurements obtained using echocardiography and DSCT were not significant (P>0.05), and the difference between the measurements obtained using both the methods were within 95% confidence intervals except those for interventricular septal thickness and left ventricular posterior wall thickness in end diastole. The reasons for these differences were considered to be the adjacent structures such as papillary muscles or chordae tendineae that may have influenced the echocardiographic findings, lower far-field image quality of echocardiography, low test-retest reproducibility of echocardiography, high-quality images of DSCT minimizing the motion artifact and the retrospective ECG gating technique of DSCT that offered an adequate timing decision for the systolic and diastolic phase during cardiac movement. Although there were differences in the measurements of interventricular septal thickness and left ventricular posterior wall thickness in end diastole obtained using echocardiography and DSCT, we could conclude that echocardiographic measurement is as accurate and reliable as DSCT for cardiac anatomical assessment.

Assessment of glomerular filtration rate with dynamic computed tomography in normal Beagle dogs.

The objective of our study was to determine individual and global glomerular filtration rates (GFRs) using dynamic renal computed tomography (CT) in Beagle dogs. Twenty-four healthy Beagle dogs were included in the experiment. Anesthesia was induced in all dogs by using propofol and isoflurane prior to CT examination. A single slice of the kidney was sequentially scanned after a bolus intravenous injection of contrast material (iohexol, 1 mL/kg, 300 mgI/mL). Time attenuation curves were created and contrast clearance per unit volume was calculated using a Patlak plot analysis. The CT-GFR was then determined based on the conversion of contrast clearance per unit volume to contrast clearance per body weight. At the renal hilum, CT-GFR values per unit renal volume (mL/min/mL) of the right and left kidneys were 0.69 ± 0.04 and 0.57 ± 0.05, respectively. No significant differences were found between the weight-adjusted CT-GFRs in either kidney at the same renal hilum (p = 0.747). The average global GFR was 4.21 ± 0.25 mL/min/kg and the whole kidney GFR was 33.43 ± 9.20 mL/min. CT-GFR techniques could be a practical way to separately measure GFR in each kidney for clinical and research purposes.

Imaging assessment of the modified double contrast barium enema using carboxymethylcellulose on radiography and ultrasonography in dogs.

A modified double contrast barium enema using carboxymethylcellulose was evaluated in beagle dogs and compared with dogs receiving a conventional barium enema. The experimental group was divided into three groups (1, 2, and 3) and given 30 ml/kg of different volume ratios of a barium vs. carboxymethylcellulose mixture. Each group underwent sonography following radiography. The volume ratio of one part barium to three parts carboxymethylcellulose was judged to be the optimal mixture, resulting in a general distribution of contrast and bowel radiolucency on radiographs and adequate postradiography sonography. The modified barium enema using carboxymethylcellulose is useful for assessing the general morphology and mucosal layers of the colon simultaneously on radiographs and ultrasonographs.

Computed tomographic evaluation of abdominal fat in minipigs.

Computed tomography (CT) exams were conducted to determine the distribution of abdominal fat identified based on the CT number measured in Hounsfield Units (HU) and to measure the volume of the abdominal visceral and subcutaneous fat in minipigs. The relationship between the CT-based fat volumes of several vertebral levels and the entire abdomen and anthropometric data including the sagittal abdominal diameter and waist circumference were evaluated. Moreover, the total fat volumes at the T11, T13, L3, and L5 levels were compared with the total fat volume of the entire abdomen to define the landmark of abdominal fat distribution. Using a single-detector CT, six 6-month-old male minipigs were scanned under general anesthesia. Three radiologists then assessed the HU value of visceral and subcutaneous abdominal fat by drawing the region of interest manually at the T11, T13, L1, L3, and L5 levels. The CT number and abdominal fat determined in this way by the three radiologists was found to be correlated (intra-class coefficient = 0.9). The overall HU ranges for the visceral and subcutaneous fat depots were -147.47 to -83.46 and -131.62 to -90.97, respectively. The total fat volume of the entire abdomen was highly correlated with the volume of abdominal fat at the T13 level (r = 0.97, p < 0.0001). These findings demonstrate that the volume of abdominal adipose tissue measured at the T13 level using CT is a strong and reliable predictor of total abdominal adipose volume.

Evaluation of triphasic helical computed tomography of the kidneys in clinically normal dogs.

OBJECTIVE: To determine computed tomography (CT) delay times by use of a sequential scan and identify the normal enhancement pattern in each phase of a triphasic CT scan of the kidneys in dogs. ANIMALS: 14 healthy Beagles. PROCEDURES: A sequential CT scan was used for investigating delay time, and a triphasic helical CT scan was used for identifying the normal enhancement pattern and determining Hounsfield unit values in the kidneys of dogs. RESULTS: In the cine scan (single-slice dynamic scan), the optimal delay times were 10 seconds in the corticomedullary phase and 44 seconds in the nephrographic phase, after contrast medium injection. By use of triphasic CT images, Hounsfield unit values were acquired in each phase. CONCLUSIONS AND CLINICAL RELEVANCE: Triphasic CT of the kidneys in clinically normal dogs was established by acquisition of delay times in a cine scan and may become an important imaging modality in the diagnosis of renal diseases and in treatment planning in dogs.

Evaluation of the effects of thiopental, propofol, and etomidate on glomerular filtration rate measured by the use of dynamic computed tomography in dogs.

OBJECTIVE: To evaluate the effects of thiopental, propofol, and etomidate on glomerular filtration rate (GFR) measured by the use of dynamic computed tomography in dogs. ANIMALS: 17 healthy Beagles. PROCEDURES: Dogs were randomly assigned to receive 2 mg of etomidate/kg (n = 5), 6 mg of propofol/kg (7), or 15 mg of thiopental/kg (5) during induction of anesthesia; anesthesia was subsequently maintained by isoflurane evaporated in 100% oxygen. A 1 mL/kg dosage of a 300 mg/mL solution of iohexol was administered at a rate of 3 mL/s during GFR measurement. Regions of interest of the right kidney were manually drawn to exclude vessels and fatty tissues and highlight the abdominal portion of the aorta. Iohexol clearance per unit volume of the kidney was calculated by use of Patlak plot analysis. RESULTS: Mean ± SD weight-adjusted GFR of the right kidney after induction of anesthesia with thiopental, propofol, and etomidate was 2.04 ± 0.36 mL/min/kg, 2.06 ± 0.29 mL/min/kg, and 2.14 ± 0.43 mL/min/kg, respectively. However, no significant differences in weight-adjusted GFR were detected among the treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results obtained for the measurement of GFR in anesthetized dogs after anesthetic induction with etomidate, propofol, or thiopental and maintenance with isoflurane did not differ significantly. Therefore, etomidate, propofol, or thiopental can be used in anesthesia-induction protocols that involve the use of isoflurane for maintenance of anesthesia without adversely affecting GFR measurements obtained by the use of dynamic computed tomography in dogs.

Computed tomography angiography for evaluation of pulmonary embolism in an experimental model and heartworm infested dogs.

This study was performed to characterize pulmonary embolism with computed tomography pulmonary angiography in experimental pulmonary embolism and heartworm infected dogs. In the experimental group, there were pulmonary changes after pulmonary embolism induction as follows: hypoattenuating round filling defects in pulmonary arteries, arterial dilations with straight and abrupt cut-off appearances in the pulmonary embolism regions, pulmonary infarctions, a cavity formation and spontaneous pneumothorax, and emboli migration. In the heartworm-infected group, three out of eight dogs developed pulmonary embolism, especially in the right caudal arteries. Arterial dilations with typical tortuosity were also identified, mainly in the right caudal arteries in five dogs. Computed tomography pulmonary angiography can be an important imaging modality in the diagnosis of pulmonary embolism and the evaluation of pulmonary arterial and parenchymal changes in dogs.

Spectral Doppler ultrasound in the major arteries of normal conscious immature micropigs.

Spectral waveform analysis of blood flow velocity in the major arteries of six healthy, conscious immature micropigs was determined using Doppler ultrasonography. Doppler spectral tracings were recorded from the external iliac artery, femoral artery, and renal arcuate artery. Tracings were also taken from three parts of the common carotid artery and two parts of the abdominal aorta. Spectral Doppler parameters included peak systolic velocity, early diastolic velocity, peak systolic velocity-to-end diastolic velocity ratio, resistive index, and pulsatility index. In addition, the diameter of major arteries and indirect blood pressure were measured. These results from spectral Doppler analysis in major arteries may be useful as reference ranges in the future studies of vascular hemodynamics in immature micropigs.

Three-dimensional CT angiography of the canine hepatic vasculature.

Eight Beagle dogs were anesthetized and were imaged using a single channel helical CT scanner. The contrast medium used in this study was iohexol (300 mg I/ml) and doses were 0.5 ml/kg for a cine scan, 3 ml/kg for an enhanced scan. The flow rate for contrast material administration was 2 ml/sec for all scans. This study was divided into three steps, with unenhanced, cine and enhanced scans. The enhanced scan was subdivided into the arterial phase and the venous phase. All of the enhanced scans were reconstructed in 1 mm intervals and the scans were interpreted by the use of reformatted images, a cross sectional histogram, maximum intensity projection and shaded surface display. For the cine scans, optimal times were a 9-sec delay time post IV injection in the arterial phase, and an 18-sec delay time post IV injection in the venous phase. A nine-sec delay time was acceptable for the imaging of the canine hepatic arteries by CT angiography. After completion of arterial phase scanning, venous structures of the liver were well visualized as seen on the venous phase.

Segmental aplasia of the uterine horn with ipsilateral renal agenesis in a cat.

A nine-month-old domestic short haired cat was admitted with the history of acute vomiting, depression and shivering. Abdominal ultrasonography revealed minimum enlargement of the right uterine horn filled with anechoic fluid. On excretory urography, functionally and anatomically normal, enlarged left kidney was found, but right kidney was absent. It was preliminary diagnosed as hydrometra with right renal agenesis. Aiming at the correction of hydrometra, we performed ovariohysterectomy. During spaying, we found a missing segment of distal part of the right uterine horn and absence of ipsilateral kidney and ureter. Compressed uterine structure and segmental aplasia of right uterine horn were found in histopathological investigation. Taken together, it was diagnosed as a segmental aplasia of uterine horn with ipsilateral renal agenesis.

Osteochondrodysplasia in three Scottish Fold cats.

This report explains typical radiographic features of Scottish Fold osteochondrodysplasia. Three Scottish Fold cats suffering from lameness were referred to the Veterinary Medical Teaching Hospital, Seoul National University, Korea. Based on the breed predisposition, history, clinical signs, physical examination, and radiographic findings, Scottish Fold osteochondrodysplasia was confirmed in three cases. Radiographic changes mainly included exostosis and secondary arthritis around affected joint lesions, and defective conformation in the phalanges and caudal vertebrae. The oral chondroprotective agents such as glucosamine and chondroitin sulfate make the patients alleviate their pain without adverse effects.