Description of the use of contrast-enhanced ultrasonography in four dogs with pancreatic tumours

Pancreatic adenocarcinoma treated with surgical resection, toceranib phosphate and firocoxib in a dog: a case report

Exocrine pancreatic carcinomas are rarely reported in dogs. A ductal pancreatic adenocarcinoma in a 10-year-old intact beagle is described in this report. The diagnosis was made based on clinical signs, imaging (abdominal ultrasound and CT scan) and histopathology. Treatment consisted of partial right lobe pancreatectomy followed by adjuvant therapy with toceranib phosphate (Palladia®) and firocoxib (Previcox®) for six months. The treatment was well tolerated, and the survival time was 445 days. To our knowledge, this is the longest survival reported in the literature for a dog diagnosed with exocrine pancreatic adenocarcinoma. The results described here may contribute to provide a better understanding about this neoplasia and potential treatment options.

Use of New Ultrasonography Methods for Detecting Neoplasms in Dogs and Cats: A Review

The aim of this literature review was to present the novel imaging modalities elastography and contrast-enhanced ultrasonography. We provided an overview of the concepts and applications of each technique for the investigation of neoplastic and metastatic tumors in dogs and cats. Studies on elastography are based on the elasticity and deformation of the evaluated tissue. The information obtained from the different types of elastography can aid in the detection and differentiation of malignant and benign structures. Descriptions of elastography studies in several organs and tissue in veterinary medicine reported that, in general, malignant tumors tend to be more rigid and, therefore, less deformable than benign lesions or in comparison to the healthy parenchyma. Contrast-enhanced ultrasonography is based on the intravenous injection of contrast media constituted by microbubbles. This imaging modality can be performed in nonsedated animals and provides information on the tissue perfusion, allowing the investigation of macro- and micro-circulation. Studies on different organs and tissues were performed in dogs and cats and revealed a tendency of malignant tumors to present faster transit of the contrast media (time to wash-in, peak and wash-out). These advanced techniques can be associated with other imaging modalities, aiding important information to the well-established exams of B-mode and Doppler ultrasonography. They can be used as screening tests, potentially representing an alternative to the invasive sampling methods required for cytological and histopathological analysis.

Contrast-enhanced ultrasound features of focal pancreatic lesions in dogs

BACKGROUND

Contrast-enhanced ultrasound (CEUS) features of pancreatic lesions are poorly reported in veterinary literature.

METHODS

Qualitative and quantitative features of pancreatic benign (nodular hyperplasia [NH], cyst and abscess) and malignant (adenocarcinoma and insulinoma) lesions during B-mode and CEUS examinations are described in 75 dogs.

RESULTS

Adenocarcinomas (n = 23) had mixed echogenicity at B-mode, and they were hypoenhancing or non-enhancing at CEUS, with a non-homogeneous and cystic enhancement pattern. Insulinomas (n = 23) appeared as hypoechoic lesions at B-mode, and as hyperenhancing, homogeneous and solid lesions at CEUS. NH (n = 17) had an constant appearance, being hypoechoic at ultrasound (US) and isoenhancing at CEUS. Cysts (n = 7) were all anechoic, with acoustic enhancement clearly detectable at US, but were non-enhancing at CEUS. Lastly, abscesses (n = 5) had mixed echogenicity, and they showed both hyperenhancement and non-enhancement at CEUS. Hypoenhancement and non-homogeneous appearance had a moderate diagnostic accuracy in the detection of adenocarcinomas. In particular, hyperenhancement was evident only in malignant lesions (adenocarcinomas and insulinomas).

CONCLUSION

CEUS, in combination with B-mode US features, is a valuable tool for distinction of benign and malignant abnormalities of the pancreas and can potentially differentiate insulinomas from adenocarcinomas.

Intrapancreatic accessory spleen mimicking pancreatic insulinoma with intrapancreatic metastasis in a cat

An 11-year-old neutered male Domestic Shorthair cat presented with a 3-month history of hypoglycemia, two episodes of seizure, and intermittent tick-like signs. Serum biochemistry revealed severe hypoglycemia associated with high insulin concentrations. Dynamic abdominal computed tomography (CT) indicated two pancreatic masses, which were enhanced most during the late arterial phase but had different degrees and variations of attenuation. Partial pancreatectomy was performed. Histopathology and immunohistochemistry confirmed that one mass was an insulinoma and the other was an ectopic splenic tissue, consistent with the differences in imaging findings. When an intrapancreatic lesion with hyper-attenuation on dynamic abdominal CT is detected, not only insulinoma or metastasis of malignancies but also intrapancreatic accessory spleen (IPAS) should be considered as differential diagnoses.

Fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography for staging of canine insulinoma: 3 cases (2019-2020)

OBJECTIVES

Canine insulinomas are uncommon malignant functional pancreatic neuroendocrine tumours with a high metastatic rate. Diagnostic imaging aids with staging and surgical planning of these tumours; however, identification is unpredictable across modalities. High-grade human pancreatic neuroendocrine tumours display increased avidity on ¹⁸ F-fluorodeoxyglucose positron emission tomography-CT.

MATERIALS AND METHODS

Dogs with clinicopathologic findings consistent with pancreatic insulinoma were prospectively enrolled. Patients underwent ¹⁸ F-fluorodeoxyglucose positron emission tomography-CT and CT angiography, followed by exploratory laparotomy.

RESULTS

Three patients met the inclusion criteria and had histologically confirmed insulinomas. Both metastatic lesions in patient 1 were mildly avid (SUV_max 2.79 and 3.01). In patient 2, the primary pancreatic insulinoma was minimally avid (SUV_max 2.16). The primary pancreatic lesion in patient 3 had similar avidity to normal pancreatic parenchyma (SUV_max 1.54) and was undetected on ¹⁸ F-fluorodeoxyglucose positron emission tomography-CT. Insulinomas demonstrated variable attenuation and contrast enhancement patterns on CT angiography and certain lesions were more conspicuous than on ¹⁸ F-fluorodeoxyglucose positron emission tomography-CT. Two metastatic lesions not visible on either imaging modality were discovered in patient 2 at surgery.

CLINICAL SIGNIFICANCE

Canine insulinomas were inconsistently avid on ¹⁸ F-fluorodeoxyglucose positron emission tomography-CT. This finding is likely attributable to the confounding clinicopathological features and multifaceted transformation of these tumours, in addition to the influence of variable tumour size, composition and vascularity. Unpredictable tumoural avidity limits the value of ¹⁸ F-fluorodeoxyglucose positron emission tomography-CT for staging canine insulinomas.

Comparison of sulfur hexafluoride microbubbles and perfluorobutane for performance of contrast-enhanced ultrasonography of the pancreas in dogs

OBJECTIVE

To compare qualitative features and quantitative parameters of 2 contrast agents (sulfur hexafluoride microbubbles [SHM; SonoVue] and perfluorobutane [PFB; Sonazoid]) for performance of contrast-enhanced ultrasonography (CEUS) of the pancreas in dogs.

ANIMALS

8 healthy Beagles.

PROCEDURES

In a crossover study design, CEUS of the pancreas was performed twice in each dog, once with SHM and once with PFB, in random order with at least 3 days between examinations. The recorded cine images were qualitatively assessed for homogeneity of pancreatic enhancement and conspicuity of the pancreatic signal relative to the background. For the quantitative assessment, circular regions of interest were placed over the pancreatic body, and a time-intensity curve was obtained. For each region of interest, CEUS parameters including peak intensity (PI), time to peak pancreatic enhancement, area under the curve (AUC), and wash-in rate were obtained.

RESULTS

The homogeneity of the pancreatic parenchyma was not significantly different between contrast agents. The signal conspicuity relative to background noise was significantly higher with PFB than with SHM. Mean values of PI, wash-in rate, and AUC were significantly higher with PFB than with SHM. Time to peak enhancement was not significantly different between contrast agents.

CONCLUSIONS AND CLINICAL RELEVANCE

Pancreatic CEUS with SHM and PFB produced similar homogeneity scores, but only PFB provided excellent signal conspicuity. Perfluorobutane produced higher values of PI, wash-in rate, and AUC. Findings indicated that PFB can provide homogeneous and strong enhancement of the pancreas during CEUS in healthy dogs and that pancreatic CEUS parameter values differ with the contrast agent used.

B-Mode and Contrast Enhanced Ultrasonography Features of Gastric Inflammatory and Neoplastic Diseases in Dogs

Simple Summary

Canine gastric disorders are common in veterinary clinical practice and among these neoplasms require rapid identification and characterization. Standard ultrasonography is the imaging modality of choice for gastric wall assessment. The aim of this prospective study is to describe the specific B-mode and contrast enhanced ultrasound features of normal, inflammatory, and neoplastic gastric diseases in dogs. Standard and contrast enhanced ultrasound of the stomach were performed in anesthetized dogs with or without gastric disorders. Gastric wall qualitative and quantitative parameters were evaluated. A total of 41 dogs were included: 6 healthy as the control group; 9 gastritis; 8 adenocarcinoma; 8 alimentary lymphoma; 4 leiomyosarcoma; 2 gastrointestinal stromal tumor; 2 leiomyoma; 1 undifferentiated sarcoma; 1 metastatic gastric hemangiosarcoma. Gastric tumors appear as a marked thickening with absent layers definition and possible regional lymphadenopathy and steatitis while gastritis generally shows no/mild thickening and no other alterations on standard ultrasound. During contrast—enhanced ultrasonography, neoplasms show a higher and faster wash in if compared to that of gastritis. B-mode and contrast enhanced ultrasound assessment may be useful in the evaluation of canine gastric disorders for the distinction between gastritis and gastric neoplasms, even if there are no specific aspects able to discriminate between different tumors types.

Abstract

Canine gastric disorders are common in veterinary clinical practice and among these neoplasms require rapid identification and characterization. Standard ultrasound (US) is the imaging modality of choice for gastric wall assessment. The aim of this prospective study is to describe the specific B-mode and contrast enhanced US (CEUS) features of normal, inflammatory, and neoplastic gastric wall in dogs. B-mode US and CEUS of the stomach were performed in anesthetized dogs with or without gastric disorders. Gastric wall qualitative and quantitative parameters were evaluated on B-mode US and CEUS examination. A total of 41 dogs were included: 6 healthy (HEA) as the control group; 9 gastritis (INF); 8 adenocarcinoma (AC); 8 alimentary lymphoma (AL); 4 leiomyosarcoma (LEIS); 2 gastrointestinal stromal tumor (GIST); 2 leiomyoma; 1 undifferentiated sarcoma; 1 metastatic gastric hemangiosarcoma. Gastric tumors appear as a marked wall thickness with absent layers definition and possible regional lymphadenopathy (AC and AL) and steatitis (AC) while gastritis generally shows no/mild thickening and no other alterations on B-mode US. On CEUS, neoplasm shows a higher and faster wash in if compared to that of gastritis. B-mode and CEUS assessment may be useful in the evaluation of canine gastric disorders in the distinction between gastritis and gastric neoplasms, even if there are no specific features able to discriminate between the different tumor histotypes.

B-Mode and Contrast Enhanced Ultrasonography Features of Gastric Inflammatory and Neoplastic Diseases in Cats

Simple Summary

Alimentary lymphoma is the most common neoplasm of the feline gastrointestinal tract. In most cases, standard ultrasonography may not be able to discriminate between a neoplastic and inflammatory infiltrate at this level. The aim of this prospective study is to establish the value of conventional ultrasound and contrast enhanced ultrasonography in describing specific features of normal, inflammatory, and neoplastic gastric diseases in feline species. A total of 29 cats were included in the study: six healthy cats as the control group; nine with gastric inflammation; three with low-grade alimentary lymphoma; 10 with high grade alimentary lymphoma. High-grade lymphoma usually appears as a severe wall thickening with absent layer definition, regional lymphadenopathy and local steatitis on a conventional ultrasound and shows a high-contrast uptake and a homogeneous enhancement with comb teeth-like vessels on contrast-enhanced ultrasound, while gastric inflammation and low-grade alimentary lymphoma showed a large overlap on both of those two ultrasonographic techniques. Diagnostic accuracy and cut-off value were calculated and found to be relevant for thickness (3.8 mm) for inflammation vs. low-grade lymphoma and “benign” vs. “malignant” as well as peak enhancement (34.87 dB) for “benign” vs. “malignant”. Thickness and peak enhancement can be useful parameters in the characterization of gastric infiltrates in cats.

Abstract

Alimentary lymphoma (AL) is the most common malignancy of the feline gastrointestinal tract and may cause variable mild to severe alteration of the gastric wall on ultrasonography (US) that can be very similar to those caused by inflammation (INF). The aim of this prospective study is to establish the value of B-mode and contrast-enhanced US (CEUS) in describing specific features of normal, inflammatory, and neoplastic gastric diseases in feline species. B-mode US and CEUS of the stomach were performed in anesthetized cats with or without gastric disorders. Gastric wall qualitative and quantitative parameters were evaluated on B-mode US and CEUS examination. A total of 29 cats were included: six healthy (HEA) cats as the control group; nine INF; three low-grade lymphoma (LGAL); 10 high-grade lymphoma (HGAL). On B-mode US, there were significant differences in thickness, the wall’s layer definition and echogenicity between HGAL and all the other groups (<0.001). For CEUS, statistical differences between groups were found in the following: HGAL vs. HEA, HGAL vs. INF; HGAL vs. LGAL; INF vs. HEA. Diagnostic accuracy (AUC) and cut-off value were calculated and found to be significant for thickness (3.8 mm) for INF vs. LGAL (AUC > 0.70) and “benign” vs. “malignant” (AUC > 0.90) as well as peak enhancement (34.87 dB) for “benign” vs. “malignant” (AUC > 0.70). INF and LGAL showed an overlap of qualitative and quantitative parameters both on B-mode and CEUS, while HGAL usually appears as a severe wall thickening with absent layer definition, high-contrast uptake, a specific enhancement pattern, regional lymphadenopathy and local steatitis. Thickness and peak enhancement can be useful parameters in the characterization of gastric infiltrates in cats.

Pancreatic Evaluation in Dogs using Different Ultrasonographic Techniques – Preliminary Results

The aim of this study is to describe the preliminary results on the accuracy of ultrasonographic techniques such as elastography, contrast enhanced ultrasound (CEUS) and Doppler in determining pancreatic changes. Twenty-five dogs, males and females, aged 1-14 years, were studied. Sixteen animals had no clinical signs of pancreatic disease (GS) and nine presented signs of pancreatic disorders (GD). All animals from GD presented sonographic changes in B-mode and qualitative elastography, with shear-wave velocity (SWV) higher (2.4±0.5m/s) in GD (p=0.014) than GS (1.9±0.3m/s) resulting in 78% sensitivity and 69% specificity in the identification of pancreatic changes. Regarding Doppler mode, no differences were observed between groups with color mapping or pulsed wave Doppler. The values obtained with CEUS did not differ between groups. Elastography is a promising technique for differential diagnosis of pancreatic changes because of its sensitivity and specificity, while the other techniques did not show diagnostic accuracy.

Histopathological findings and canine pancreatic lipase immunoreactivity in normal dogs and dogs with inflammatory and neoplastic diseases of the pancreas

BACKGROUND

Diagnosis of pancreatic diseases in dogs is still challenging because of variable clinical signs, which do not always correspond with clinical pathology and histopathological findings.

OBJECTIVES

To characterize inflammatory and neoplastic pancreatic diseases of dogs and to correlate these findings with clinical findings and canine pancreatic lipase immunoreactivity (cPLI) results.

ANIMALS

Tissue specimens and corresponding blood samples from 72 dogs submitted for routine diagnostic testing.

METHODS

Four groups were defined histologically: (1) normal pancreas (n = 40), (2) mild pancreatitis (n = 8), (3) moderate or severe pancreatitis (acute, n = 11; chronic, n = 1), and (4) pancreatic neoplasms (n = 12). An in-house cPLI ELISA (<180 μg/L, normal; >310 μg/L, pancreatitis) was performed.

RESULTS

In dogs with normal pancreas, 92.5% of serum cPLI results were within the reference range and significantly lower than in dogs with mild acute pancreatitis, moderate or severe acute pancreatitis and pancreatic tumors. In dogs with moderate or severe acute pancreatitis, cPLI sensitivity was 90.9% (95% confidence interval [CI], 58.7%-99.8%). Most dogs (9/12) with pancreatic tumors (group 4) had additional pancreatic inflammation and cPLI results were increased in 10 dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

High cPLI indicates serious acute pancreatitis but underlying pancreatic neoplasms should also be taken into consideration. This study confirms the relevance of histopathology in the diagnostic evaluation of pancreatic diseases.

Characterization of 22 Canine Pancreatic Carcinomas and Review of Literature

Pancreatic carcinomas are rare in dogs and clinical signs are mostly non-specific. The literature on clinically and pathologically characterized canine exocrine pancreatic tumours is limited to 76 cases reported since 1963. This retrospective study analysed formalin-fixed samples of pancreatic carcinomas from 22 dogs, obtained during elective exploratory surgery (n = 16) or if the dog was humanely destroyed (n = 6). Tumours were diagnosed according to the World Health Organization classification of tumours of the pancreas of domestic animals. In seven cases, blood samples taken during or shortly before surgery were analysed for concentrations of alpha-amylase, 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methylresorufin) ester lipase (DGGR lipase), C-reactive protein (CRP), alanine aminotransferase, glutamate dehydrogenase, alkaline phosphatase (ALP), canine trypsin-like immunoreactivity (cTLI) and canine pancreatic lipase immunoreactivity (cPLI). Neutrophil and lymphocyte numbers were determined as part of a complete blood count. Clinical signs were non-specific and included vomiting, inappetence and diarrhoea. Acinar carcinomas were most common (19/22) and observed growth patterns included: solid (n = 14), acinar (n = 5), clear cell (n = 3), mucinous (n = 2), trabecular (n = 1) or rosette-like (n = 1), occurring as a single pattern or in combination. Ductal carcinomas were identified in three cases. Pancreatitis was a common additional histological finding; five dogs had mild and nine dogs had severe pancreatitis. cPLI, DGGR lipase, cTLI and CRP were elevated in 5/5 acinar carcinomas. All liver enzymes were elevated in three of these five animals and ALP was increased in 4/5 dogs. Two dogs with ductal pancreatic carcinomas showed normal cPLI concentrations. One had increased CRP, liver enzymes and leucocytosis with neutrophilia, the other had elevated DGGR lipase and cTLI concentrations. Clinical findings in canine pancreatic carcinomas were non-specific and simultaneous inflammation can mask the detection of the underlying neoplasm in clinical examination and laboratory testing.

Contrast-enhanced ultrasonography features of hepatobiliary neoplasms in cats

BACKGROUND

Contrast-enhanced ultrasonography (CEUS) features of primary hepatobiliary neoplasms have been reported in dogs but no information is available in cats.

METHODS

Qualitative and quantitative features of bile duct adenomas (BDAs, n=20), bile duct carcinomas (BDCs, n=16), and hepatocellular carcinomas (HCCs, n=8) are described in 44 cats.

RESULTS

There was an overlap in CEUS qualitative features between different histotypes, both in wash-in and wash-out phases. Distinction between different neoplasms based only on the CEUS qualitative features was not possible. At peak of enhancement, the BDAs, BDCs and HCCs showed a large range of echogenicities, from hypoenhancement to hyperenhancement, in comparison to the liver parenchyma. Eight of 20 BDAs showed inhomogeneous hyperenhancement during wash-in, which is a feature reported as typical of malignant lesions in dogs. BDC had a significantly faster wash-in compared with both BDA and HCC but the diagnostic accuracy of all the included quantitative variables was only moderate. No significant differences in the wash-out quantitative features of BDA and BDC were evident.

CONCLUSION

There is poor evidence that CEUS may be used to distinguish between different primary hepatobiliary neoplasms in cats.

Use of contrast-enhanced ultrasonography for the detection of a feline insulinoma

Case summary

A 14-year-old cat was presented with a 2-week history of ataxia, seizure-like episodes, vomiting and weight loss. Serum biochemistry revealed severe hypoglycaemia, associated with low serum fructosamine and high insulin concentrations. On abdominal ultrasound, a focal hypoechoic well-defined mass in the left limb of the pancreas was identified and the presence of an additional smaller nodule was suspected. Contrast-enhanced ultrasonography (CEUS) confirmed the presence of both lesions and revealed a third, even smaller nodule. Partial pancreatectomy was performed. Histopathology and immunohistochemistry confirmed the presence of a multifocal insulinoma. Six months later, the cat presented with tenesmus and obstipation. A colorectal adenocarcinoma was diagnosed with histopathology after partial excision of a colorectal mass. The cat was euthanased a month later owing to recurrent episodes of severe obstipation.

Relevance and novel information

This is the first clinical description of the use of CEUS in the diagnosis of feline insulinoma. Furthermore, the available scientific literature on feline insulinoma was reviewed.

Canine insulinomas appear hyperintense on MRI T2-weighted images and isointense on T1-weighted images

Clinical and imaging diagnosis of canine insulinomas has proven difficult due to nonspecific clinical signs and the small size of these tumors. The aim of this retrospective case series study was to describe MRI findings in a group of dogs with pancreatic insulinomas. Included dogs were presented for suspected pancreatic insulinoma, MRI was used to assist with localization of the primary lesion, and the diagnosis was confirmed with surgical exploratory laparotomy and histopathology. The MRI studies for each dog were retrieved and the following data were recorded: T1-weighted and T2-weighted signal intensities, type of contrast enhancement, size and location of the primary lesion, and characteristics of metastatic lesions (if present). A total of four dogs were sampled. In all patients, the insulinoma displayed high-intensity signal on T2-weighted fat saturation images, similar to human studies. On postcontrast T1-weighted fat saturation images, the tumors were primarily isointense to normal pancreatic tissue, in contrast to human studies where a low-intensity signal is typically identified. Abnormal islet tissue was detected with MRI in all four dogs and metastases were identified in three dogs. Variations in the MRI appearance of primary and metastatic lesions were identified and could have been related to the variation of tissue composition, including the presence of neoplastic cells, hemorrhage, and fibrovascular stroma, and to the transformation of this tissue throughout the disease process.

Cytologic findings and diagnostic yield in 92 dogs undergoing fine-needle aspiration of the pancreas

The diagnosis of pancreatic disease in small animal veterinary patients is complicated by nonspecific clinical signs and the limitations of diagnostic testing. Pancreatic cytology is a potential diagnostic tool, but safety and diagnostic yield are not well characterized in large patient cohorts. We hypothesized that pancreatic fine-needle aspiration (FNA) in dogs would frequently generate diagnostic-quality samples and subsequent adverse medical events would be uncommon. Ninety-two client-owned dogs undergoing pancreatic FNA for clinical diagnostic evaluation were identified retrospectively by a computer search for pancreatic cytology submissions. Archived slides were reviewed by a single board-certified clinical pathologist using a predetermined descriptive scheme. Medical records were reviewed for adverse events 48 hr following FNA, for concurrent procedures and diagnosis in patients with adverse events and for histology results. Diagnostic yield was calculated as the % cases in which a cytologic diagnosis could be achieved; correlation with histology or other confirmatory testing was determined when possible. Diagnostic yield was 73.5%, and the major pathologic process identified cytologically correlated with confirmatory testing in 10 out of 11 cases. There were 7 adverse events, all in dogs with significant comorbidities or undergoing other invasive procedures. Pancreatic FNA in dogs has a good diagnostic yield and a low rate of clinical complications in a large case series of dogs. Correlation of cytology and histology results was high in a limited number of cases.

Characterization of triple-phase computed tomography in dogs with pancreatic insulinoma

Little information is available regarding triple-phase computed tomography (CT) of canine pancreatic insulinoma. A few case reports with small numbers of cases have indicated that hyper-attenuation in the arterial phase was a common finding on multi-phasic CT in dogs with insulinoma. Our purpose was to clarify the characteristic findings of dogs with insulinoma on triple-phase CT. Nine dogs with insulinoma that underwent triple-phase CT were included in the present study. Attenuation patterns in the arterial phase indicated hypo-attenuation in 4 cases and hyper-attenuation in 2 cases. In the remaining 3 cases, 1 case showed hypo-attenuation and 1 case showed hyper-attenuation in the pancreatic phase, and 1 case presented hyper-attenuation in the later phase. Altogether, 5 cases showed hypo and 4 cases showed hyper-attenuation in at least one phase. The enhancement pattern was homogenous in 7 cases and heterogeneous in 2 cases. Tumor margins were well-defined in 5 cases and ill-defined in 4 cases. Capsule formation was present in 5 cases and absent in 4 cases. In conclusion, it is important to note that hypo-attenuation was as common as hyper-attenuation in dogs with insulinoma in triple-phase CT in at least one phase. Additionally, mass lesions were most conspicuous not only in the arterial phase but in the pancreatic and later phases in some cases. Therefore, it is important to perform triple-phase CT and notice about variable findings for the detection of canine pancreatic insulinoma.

Establishment of optimal scan delay for multi-phase computed tomography using bolus-tracking technique in canine pancreas

To establish a protocol for a multi-phase computed tomography (CT) of the canine pancreas using the bolus-tracking technique, dynamic scan and multi-phase CT were performed in six normal beagle dogs. The dynamic scan was performed for 60 sec at 1-sec intervals after the injection (4 ml/sec) of a contrast medium, and intervals from aortic enhancement appearance to aortic, pancreatic parenchymal and portal vein peaks were measured. The multi-phase CT with 3 phases was performed three times using a bolus-tracking technique. Scan delays were 0, 15 and 30 in first multi-phase scan; 5, 20 and 35 in second multi-phase scan; and 10, 25 and 40 sec in third multi-phase scan, respectively. Attenuation values and contrast enhancement pattern were analyzed from the aorta, pancreas and portal vein. The intervals from aortic enhancement appearance to aortic, pancreatic parenchymal and portal vein peaks were 3.8 ± 0.7, 8.7 ± 0.9 and 13.3 ± 1.5 sec, respectively. The maximum attenuation values of the aorta, pancreatic parenchyma and portal vein were present at scan sections with no scan delay, a 5-sec delay and a 10-sec delay, respectively. When a multi-phase CT of the canine pancreas is triggered at aortic enhancement appearance using a bolus-tracking technique, the recommended optimal delay times of the arterial and pancreatic parenchymal phases are no scan delay and 5 sec, respectively.

Contrast-enhanced ultrasonography of the pancreas in healthy cats

BACKGROUND

This study describes the pattern of ultrasonographic contrast enhancement of the pancreatic body and left lobe using a second-generation commercial contrast medium (Sonovue) in 10 clinically healthy cats.

RESULTS

Following contrast medium administration, microbubbles were observed within the splenic artery. This was followed by an inflow of contrast medium into the pancreatic capillary beds, providing a uniformly contrast-enhanced pancreas at peak intensity (PI). At the time of PI, a replenishment of the splenic and portal veins started and increased progressively during the wash-out phase. During the wash-out phase, the echogenicity of the pancreatic parenchyma decreased progressively. Perfusion parameters included arrival time (4.69 ± 1.26 s), time to peak from injection (7.52 ± 1.88 s), time to peak from initial rise (2.84 ± 0.88 s), peak intensity (6.58 ± 2.66 a.u.), and wash-in rate (2.11 ± 1.79 a.u./s).

CONCLUSIONS

This perfusion pattern of normal pancreatic parenchyma may be useful for characterising cats with exocrine pancreatic disorders.

Quantitative contrast-enhanced ultrasonographic assessment of naturally occurring pancreatitis in dogs

BACKGROUND

Quantitative contrast-enhanced ultrasonography (CEUS) can detect pancreatic perfusion changes in experimentally induced canine pancreatitis. However, its usefulness in detecting perfusion changes in naturally occurring pancreatitis is unclear.

HYPOTHESIS/OBJECTIVES

To determine the feasibility of using CEUS to detect pancreatic and duodenal perfusion changes in naturally occurring canine pancreatitis.

ANIMALS

Twenty-three client-owned dogs with pancreatitis, 12 healthy control dogs.

METHODS

Dogs diagnosed with pancreatitis were prospectively included. CEUS of the pancreas and duodenum were performed. Time-intensity curves were created from regions of interest in the pancreas and duodenum. Five perfusion parameters were obtained for statistical analyses: time to initial up-slope, peak time (Tp), time to wash-out (TTW), peak intensity (PI), and area under the curve (AUC).

RESULTS

For the pancreas, Tp of the pancreatitis group was prolonged when compared to controls (62 ± 11 seconds versus 39 ± 13 seconds; P < .001). TTW also was prolonged but not significantly (268 ± 69 seconds versus 228 ± 47 seconds; P = .47). PI and AUC were increased when compared to controls (95 ± 15 versus 78 ± 13 MPV; P = .009 and 14,900 ± 3,400 versus 11,000 ± 2,800 MPV*s; P = .013, respectively). For the duodenum, PI and AUC were significantly increased in the pancreatitis group when compared to controls.

CONCLUSIONS AND CLINICAL IMPORTANCE

Contrast-enhanced ultrasonography can detect pancreatic perfusion changes in naturally occurring canine pancreatitis characterized by delayed peak with prolonged hyperechoic enhancement of the pancreas on CEUS. Additionally, duodenal perfusion changes secondary to pancreatitis were observed.