ObjectivesThe medullary rim sign (MRS) is an ultrasonographic (US) feature identified in normal and diseased feline kidneys. The prevalence and potential clinical significance of the MRS in a referral hospital cat population was investigated.MethodsRetrospective case–control study. US images from 661 cats were reviewed. Cats with an MRS were identified and compared with equal number of time-matched control cats. Medical data and MRS features, including thickness, intensity and symmetry, were collected. Associations between independent variables and the MRS were examined with conditional and unconditional logistic regression, with initial univariable, and subsequent multivariable analysis.ResultsOf the 661 reviewed cats, 243 (36.8 per cent) showed a variation of the MRS. A thin MRS (133 cats) was not associated with azotaemic renal disease (P=0.87). A thick MRS (110 cats) was associated with azotaemic renal disease (P=0.001). There was an association between the presence of MRS and a final diagnosis of feline infectious peritonitis (FIP) (P=0.028).ConclusionsThe MRS is a common finding in cats. In this cat population, a thick MRS was associated with azotaemic renal disease, while a thin MRS was not. In cases with a clinical suspicion of FIP, the MRS may be related to the underlying disease process and not be an incidental finding.

OBJECTIVE To determine the mean diameter of the main portal vein (PV) in healthy dogs by use of CT angiography, identify any associations between PV diameter and certain dog characteristics, and validate a clinically valuable ratio for quantifying the size of the PV. ANIMALS 100 dogs with no hepatic, cardiac, or vascular anomalies that underwent abdominal CT angiography. PROCEDURES Diameters of the main PV, abdominal aorta (Ao), and caudal vena cava (CVC) were measured by 2 observers at a defined location on postcontrast CT angiographic images in axial, sagittal, and transverse planes. Dog characteristics were evaluated for associations with PV diameter, and a PV:Ao diameter ratio was calculated. Intraclass correlations were calculated to assess intra- and interobserver agreement in vessel diameter measurements. RESULTS Mean diameter values were 7.9 mm (range, 4.1 to 14.8 mm) for the PV, 8.9 mm (range, 3.7 to 13.7 mm) for the Ao, and 11.4 mm (range, 4.4 to 22.5 mm) for the CVC. The PV:Ao diameter ratio was 0.91 mm. The PV diameter was significantly associated with dog body weight but not with dog age, sex, or neuter status. Intra- and interobserver reliabilities for measurements of all 3 vessels were considered excellent (intraclass correlation coefficients > 0.85). CONCLUSIONS AND CLINICAL RELEVANCE Findings indicated that the PV:Ao diameter ratio was a repeatable measurement that may be useful for evaluating the size of the portal vasculature in dogs and possibly for distinguishing healthy PVs from abnormal PVs in dogs with hepatic vascular anomalies.

A 13-year-old neutered male domestic shorthaired cat presented to a primary care practice with a few days history of dyspnoea. Pleural effusion was diagnosed radiographically. Thoracocentesis was performed and analysis of the effusion was consistent with a lymphocyte-rich effusion (presumed chylothorax). The cat was referred for further investigations to determine the cause of the effusion. Subsequent CT and echocardiography revealed a heart base mass that was seen to infiltrate the interventricular septum. Fine needle aspiration of the mass was performed. Cytological evaluation revealed it to be neuroendocrine in origin, consistent with a chemodectoma. There was no evidence of metastatic disease. The cat was discharged for palliative care only and survived symptom free for a further six weeks at which time it was euthanased due to recurrence of pleural effusion. To the authors’ knowledge this is the first reported case of lymphocyte-rich effusion due to a chemodectoma in a cat.

This case report describes a dog with an infiltrative intramuscular lipoma in the antebrachium, presenting with chronic left forelimb lameness and altered posture of the digits. Computed tomography showed a fat-attenuating mass displacing the flexor tendons. The mass was surgically excised along with the affected muscle belly and tendon; histopathological examination revealed infiltration of adipose tissue cells within the muscle belly and tendon sheath of the deep digital flexor muscle. After removal of the lipoma, lameness resolved, full ambulatory function returned, without recurrence at 1 year follow-up.

Background Computed tomography (CT) and ultrasonography (US) may be used to assist staging in dogs with lymphoma. The imaging features of splenic and hepatic infiltration have never been directly compared in the same population of dogs. Methods The aim of this retrospective study was to describe and compare the CT and US findings of the liver and spleen in dogs with confirmed hepatic and/or splenic lymphoma and compare imaging and cytological diagnoses. Results CT and US studies of 18 dogs with multicentric lymphoma involving the liver and/or the spleen were retrospectively evaluated. US detected abnormalities more frequently than CT in the spleen with lymphoma, whereas CT detected abnormalities more frequently in the liver with lymphoma. The two diagnostic imaging modalities often disagreed in the findings, including the imaging classification of the organ as normal or abnormal. Conclusion US and CT often disagree in the imaging findings present in hepatic and splenic lymphoma. The results of this study suggest that cytologic evaluation of both the liver and spleen is advisable regardless of their US or CT appearance for detection of lymphoma.