Veterinary Radiology & Ultrasound最新文献

A 6-month-old, intact female Boxer presented with ongoing dyspnea, nasal congestion, cardiac arrhythmias, stertor, and syncope. A CT assessment of the head, neck, thorax, and abdomen revealed a fluid to soft tissue attenuating mass with an incomplete mineralized rim centered on the soft tissue ventral to the right tympanic bulla. Histopathologically, epithelialization was consistent with a dermoid cyst. The severe degree of mass effect caused by this abnormally and undocumented ossified structure in vital cranial cervical organs causes more systemic complications than traditional dermoid cysts. CT delineated the cyst's structure and compression/occlusion of adjacent structures.

A 13-year-old castrated male Shetland sheepdog presented with loss of appetite, jaundice, and lethargy. Abdominal ultrasonography revealed a hypoechoic mass in the midline of the liver relative to the normal liver parenchyma. CT revealed a hepatic mass with low attenuation (28 HU) on precontrast CT and peripheral contrast enhancement in all phases: arterial phase (93 HU), portal phase (102 HU), and delayed phase (86 HU). The mass size was 4.6 × 3.2 × 3.4 cm. Postmortem MRI findings showed that the hepatic mass had low and high signal intensities on T1 and T2-weighted images, respectively. Histopathological assessment revealed leiomyosarcoma based on morphological and immunohistochemical findings. No tumors other than those in the liver were found; therefore, a diagnosis of primary hepatic leiomyosarcoma was made.

A 2-year-old neutered male European Shorthair cat was presented for multiple bone proliferations evolving over 3 months and stridor. The osseous masses on the tarsus, vertebral column, and distal third of ribs diaphysis were confirmed by radiographs. A whole-body CT examination was performed, revealing two other masses, one on the left calvarium and one arising from the left epihyoid bone, with the latter thought to be responsible for the stridor. Histopathology confirmed a diagnosis of feline osteochondromatosis. Surgical removal of the epihyoid mass was declined due to the high recurrence rate reported.

A 6-year-old intact male guinea pig was presented for acute abdominal pain, anorexia, and absence of ambulation for 12 h. Radiographs revealed moderate gastric dilation and multifocal marked small intestinal gas dilation. Ultrasonography showed a focally dilated jejunal loop with abrupt narrowing and torsion, with a mesenteric vascular "whirl sign". The aborad jejunum was empty. Surgery revealed a focal mesenteric torsion with associated segmental jejunal torsion and consequent jejunal occlusion. A cardiopulmonary arrest occurred during the surgery. This is the first report of diagnostic imaging findings associated with mesenteric torsion in a guinea pig.

Feline inflammatory laryngeal disease is a nonneoplastic condition with limited documentation in veterinary literature. This retrospective study assesses the imaging characteristics and clinical outcomes of seven cats diagnosed with this disease. Radiography, echolaryngography, and endoscopy identified laryngeal masses or thickening in all cases. Echolaryngography, utilizing an 18 MHz high-frequency probe and spatial compounding, revealed abnormalities in shape, margination, echogenicity, echotexture, and laryngeal immobility, closely aligning with endoscopic findings. Histopathology revealed neutrophilic, lymphocytic, and lymphoplasmacytic inflammation, alongside granulation tissue formation. Disease-related mortality occurred between 19 and 90 days, while long-term survivors were followed for up to 801 days. The study highlights the difficulty in differentiating inflammatory and neoplastic lesions based on imaging alone, stressing the importance of biopsy for definitive diagnosis. Echolaryngography proved to be a valuable noninvasive diagnostic tool, providing detailed insights into laryngeal structure and function. These findings support its integration into routine diagnostic protocols for feline laryngeal disease while emphasizing the critical role of histopathological confirmation. Further research is warranted to refine imaging techniques and improve diagnostic accuracy, particularly in distinguishing between inflammatory and neoplastic conditions.

In this analytical cross-sectional method comparison study, we evaluated brain MR images in 30 dogs and cats with and without using a DICOM-based deep-learning (DL) denoising algorithm developed specifically for veterinary patients. Quantitative comparison was performed by measuring signal-to-noise (SNR) and contrast-to-noise ratios (CNR) on the same T2-weighted (T2W), T2-FLAIR, and Gradient Echo (GRE) MR brain images in each patient (native images and after denoising) in identical regions of interest. Qualitative comparisons were then conducted: three experienced veterinary radiologists independently evaluated each patient's T2W, T2-FLAIR, and GRE image series. Native and denoised images were evaluated separately, with observers blinded to the type of images they were assessing. For each image type (native and denoised) and pulse sequence type image, they assigned a subjective grade of coarseness, contrast, and overall quality. For all image series tested (T2W, T2-FLAIR, and GRE), the SNRs of cortical gray matter, subcortical white matter, deep gray matter, and internal capsule were statistically significantly higher on images treated with DL denoising algorithm than native images. Similarly, for all image series types tested, the CNRs between cortical gray and white matter and between deep gray matter and internal capsule were significantly higher on DL algorithm-treated images than native images. The qualitative analysis confirmed these results, with generally better coarseness, contrast, and overall quality scores for the images treated with the DL denoising algorithm. In this study, this DICOM-based DL denoising algorithm reduced noise in 1.5T MRI canine and feline brain images, and radiologists' perceived image quality improved.

Exploratory tenoscopy is considered the gold standard technique to identify intrathecal pathology of the equine carpal flexor tendon sheath (CFTS). Preoperative diagnosis allows for more precise prognostication and surgical planning, potentially associated with improved surgical outcomes. This prospective, descriptive, anatomical study aimed to describe the anatomy of the equine CFTS using noncontrast and contrast CT in clinically normal cadaver limbs. Ten pairs of equine forelimbs free of gross external abnormalities were examined from mid-antebrachium to distal metacarpus. Specimens initially underwent noncontrast CT examination using 135 kVp, dynamic mAs, and 1 mm slice thickness. Contrast media (iohexol) diluted in saline (total 60 mL, final concentration 75 mg/mL) was injected into the CFTS from a lateral approach before the CT examination was repeated. Tenoscopy was then performed using the conventional lateral approach. Dissection was used to compare the gross, tenoscopic, and imaging findings. The combined noncontrast CT and contrast CT examinations provided excellent anatomical detail of intrathecal and extrathecal structures. Detailed anatomy of the previously undescribed proximal mesotenon and manica of the common mesotenon were also identified. The distal termination of the CFTS was beyond the mid-metacarpus in most specimens, which is significantly more distal than previously reported. This is an important consideration when administering local anesthesia in orthopedic examinations to prevent potential iatrogenic CFTS penetration, which may induce sepsis if the aseptic technique is not followed. Noncontrast and contrast CT can be used to accurately identify CFTS anatomy. Documentation of new intrathecal structures provides a greater understanding of CFTS anatomy.

Aberrant right subclavian arteries (ARSAs) are a form of vascular ring anomaly (VRA) in dogs and the most common VRA in people. To date, there has been no large-scale study on ARSA in dogs and their potential clinical significance. For part one, a single-center retrospective observational study was performed to determine the prevalence of ARSAs in a population of 1000 dogs undergoing contrast-enhanced CT for various reasons. For part two, further canine ARSA cases were collected to characterize their imaging features further and determine whether any imaging findings were more frequent in dogs with clinical signs attributed to a VRA. The prevalence of ARSA was 1.2% (12/1000). For part two, out of a total of 37 dogs with ARSA, this finding was thought to be incidental in 28 cases (75.6%), clinically relevant in 1 case (2.7%), and potentially relevant in 8 cases (21.6%). Cranial esophageal dilation with gas and fluid and esophageal compression at the site of the ARSA crossing the esophagus was found in the case where the ARSA was considered relevant. Esophageal dilation with esophageal compression by the ARSA was also more frequent in the potentially relevant group. Our study shows that an ARSA is more likely to be an incidental finding; however, due to the low number of cases where the ARSA was considered relevant, no specific imaging findings were found that could help determine their clinical relevance.

Longissimus muscles (LM) in sheep are important for animal scientists who study meat quality and translational researchers who study thoracolumbar spinal disease. Computed tomography (CT) is an established technique for characterizing paraspinal muscles in sheep; however, studies reporting reproducibility of CT measures using open-source software are lacking. The objectives of this prospective pilot study were to develop a standardized protocol for measuring LM area and density in sheep using CT and to determine the reproducibility for measurements. Thoracolumbar CT images were acquired for four sheep at five time points each as part of another study. Six observers applied a standardized CT image analysis protocol to record triplicate transverse area (cm²) and water phantom-corrected mean density (Hounsfield units, HU) values for the left and right LM. Average coefficients of variation (CVs) for 4 of 6 observers were good to excellent (<10%) for all variables. Average CVs did not differ among observers for 3 of 4 variables (ANOVA, p > .05).

Canine congenital intrahepatic portosystemic shunts originate from the right or left portal branch and are either intralobar or interlobar. A patent ductus venosus (PDV) is an interlobar shunt that arises from the left portal branch and traverses the ligamentum venosum fissure (LVF) between the left lateral liver lobe and the papillary process of the caudate liver lobe. Identifying the LVF may aid in PDV diagnosis during ultrasonography. In this prospective exploratory study, the ultrasonographic appearances of the LVF and adjacent structures were described in 24 dogs without hepatobiliary disease. Four intercostal acoustic windows were used, two on each side of the dog, and detectability of the following structures was recorded: aorta, left portal branch, caudal vena cava, papillary process, LVF, left lateral hepatic lobe, and ligamentum venosum. All structures were found in each dog from at least one window, with varying frequencies of detection per window. At least one window provided dynamic observation of the left lateral liver lobe, LVF, papillary process, and caudal vena cava aligned left to right, craniodorsal to and parallel with the long axis of the left portal branch. Probe placement on the left hypochondriac region (left dorsal to the xiphoid process) provided the best window, followed by the right hypochondriac region. More dorsal windows (costal regions) were less useful, especially on the left. The LVF was visible in all dogs (100%) from the left hypochondriac window and in 19 dogs (79%) from the right hypochondriac window, justifying further investigation in dogs with intrahepatic portosystemic shunts.