Veterinary Radiology & Ultrasound最新文献

Pneumorrhachis is a rare condition in human and veterinary medicine, defined as gas within the vertebral canal. Iatrogenic causes are the most common source of nontraumatic PR reported in humans. PR has been recognized in dogs undergoing routine CT. This study aims to identify the cause, prevalence, and distribution of PR and intraforaminal gas in dogs undergoing CT and identify any immediate post-CT complications. The medical records of dogs who underwent CT of the thorax, abdomen, and pelvis were retrospectively reviewed. Dogs were excluded if they presented with a history of trauma, neurologic deficits, recent surgery, or epidural injection. PR and intraforaminal gas were identified as present or absent and quantified subjectively. Patient positioning, intravenous catheter location, and complications in the 24 h following CT were recorded. 50/263 (19%) dogs with PR met the inclusion criteria. All dogs with PR had CT performed in sternal recumbency. Catheters were evenly distributed in laterality of placement, yet PR was predominantly right-sided (74%). The volume of gas identified was mild (87%) or moderate (13%). An increase in the amount of PR in postcontrast images was documented in 13 cases (20%). Intraforaminal gas was identified in 16.3% of dogs, and 88.4% had right-sided intraforaminal gas. No dogs developed neurologic deficits 24 h post-CT. The prevalence of PR and intraforaminal gas in this study was significantly higher than previously documented. Intravascular right-sided gas is proposed to be secondary to the ipsilateral location of the azygous vein and of no clinical significance.

Magnetic resonance imaging often needs to be complemented with CT for complete assessment of bony structures due to CTs increased spatial resolution and discrimination of cortical bone margins. The aims of this prospective method comparison study were to perform qualitative and quantitative comparisons of standard MR sequences with three short/ultra-short TE MR sequences using CT as the gold standard. Eight healthy research dogs of similar size had CT and MR of the head performed. Three short/ultra-short TE sequences, VIBE, PETRA, and UTE, alongside standard T2W, PD, and T1W TSE sequences of the head were obtained. Slice thickness of CT and short TE MR sequences were matched. A qualitative scale was used to assess the visibility of cortical margins and skull foramina. For the quantitative assessment, predetermined osseous structures and foramina on designated slices were measured. Levene's test and post hoc folded F tests with false discovery rate adjustments were applied to the residuals from these models to compare precision relative to CT across the sequence types. The short/ultra-short TE MR sequences were significantly better than the standard MR sequences for quantitative assessment of bone thickness of smaller structures and overall qualitative assessment. Any of these short/ultra-short TE sequences may be viable to incorporate into a clinical setting as an alternative to CT to help further evaluate the skull and reduce anesthesia time and client cost. VIBE, PETRA, and UTE sequences have diagnostic image quality and provide a consistent quantitative and qualitative assessment of the cortical bone of the skull when compared with CT.

A 4.5-month-old female intact Doberman was referred for acute on chronic gastrointestinal signs and acute lethargy, polyuria, and polydipsia. Abdominal ultrasonography revealed marked focal dilatation, thrombosis, and suspect phlebitis of the caudal vena cava (CVC; renal segment). The prehepatic CVC was not identified; however, an enlarged azygos vein was identified as cranial to the dilated vessel. The patient was humanely euthanized, and a necropsy confirmed congenital segmental aplasia of the prehepatic CVC with azygos continuation complicated by thrombophlebitis. While this vascular malformation has been documented in canines, this is the first reported case of concurrent thrombophlebitis.

Although lens diseases are uncommon in horses, they can be disabling in advanced stages. The B-mode ultrasound is useful for diagnosing and monitoring the progression of ocular diseases such as cataracts. Elastography is an ultrasonographic technique that allows the detection and measurement of tissue stiffness. This observational cohort prospective study aimed to determine the feasibility, reproducibility, and repeatability of 2D-shear wave elastography (2D-SWE) of lenses in horses. Forty-six eyes of 23 horses with no evidence of ocular disease were included in this study. The horses underwent an ophthalmic examination to ensure that they were healthy. After the B-mode ultrasound examination, 2D-SWE was performed by two operators with different levels of experience in diagnostic imaging. Elastographic images were independently analyzed quantitatively by two observers by measuring the shear wave velocity (m/s) and Young's modulus (kPa). Considering both right and left eyes, the mean shear wave velocity was 4.08 ± 0.71 m/s, and the mean Young's modulus was 51.30 ± 19.02 kPa. Interoperator and intraoperator agreements were excellent. The intra-observer agreement was good, with only one value for each observer that presented statistically significant differences. No statistically significant differences were observed between the right and left eyes. The excellent reliability, reproducibility, and good repeatability between evaluators make 2D-SWE a practical and reproducible technique that can be applied in clinical settings, where different sonographers often obtain images on multiple separate occasions. Our findings support the future clinical application of 2D-SW elastography as a noninvasive imaging modality for normal lens evaluation in horses.

The heart-to-single vertebra ratio (HSVR) has been proposed as a simple, quick, and reliable radiographic method to assess cardiac silhouette dimensions in dogs. The HSVR shows excellent agreement with the vertebral heart size (VHS), and it can also be accurately determined in dogs with vertebral abnormalities affecting the thoracic spine. This retrospective, single-center, method-comparison, observer-agreement study investigated the reliability of the HSVR in cats. Three observers retrospectively evaluated anonymized right-lateral thoracic radiographs obtained over a set period of time. Exclusion criteria included the presence of thoracic spine alterations and the inability to outline the cardiac silhouette. The HSVR was calculated by dividing the sum of the cardiac long and short axes by the length of each vertebral body from T4 to T8. Images of 101 cats of different breeds met the inclusion criteria. Lin's concordance correlation coefficient and the relative 95% confidence interval (CI) revealed that the HSVR^T6 showed the best agreement with the VHS (0.95; 95% CI: 0.91-0.97). Bland-Altman plots showed low bias (-0.023 ± 0.19; limits of agreement = -0.39 to 0.35) between the HSVR^T6 and the VHS, with low mean absolute error (0.14; 95% CI: 0.12-0.17) between the two methods. The intraclass correlation coefficients, evaluated on 20 cats, demonstrated excellent interobserver agreement (0.95-0.96; p < .001) and good to excellent intraobserver agreement (0.75-0.94; p < .001) for all HSVRs. The results of this study confirmed that the HSVR is a simple, quick, and reliable alternative to the VHS also in cats.

A 16-month-old intact male Selkirk Rex cat was referred for recurrent hematuria, dysuria, and oliguria. Cystitis with a bladder calculus was diagnosed, and an incidental finding of a splenocaval extrahepatic portosystemic shunt with malformation of the left hepatic vein was discovered. Computed tomographic angiography demonstrated the left hepatic vein crossed the diaphragm, coursed along the left side of the caudal vena cava, and drained into the right atrium. Cellophane banding of the portosystemic shunt was performed. An anomalous left hepatic vein is extremely rare in humans, and this is the first report of such an anomaly in the veterinary literature.

Computed tomography is commonly used to investigate pathologies of the lower urogenital tract in female dogs. Even though a positive contrast medium is commonly used, negative contrast has proven to be a valuable tool in the assessment of urinary pathologies. This study aims to compare the use of negative with positive retrograde CT vaginography in the assessment of the lower urogenital tract in female dogs. This retrospective method comparison study gathered 30 cases retrieved from the database of three referral hospitals and equally divided them into two groups: positive CT vaginography group and negative CT vaginography group. Criteria for inclusion were CT images of the entire urogenital tract before and after intravenous contrast agent injection, followed by retrograde vaginography. The degree of visibility of seven anatomical structures from the fossa clitoridis to the cervix was blindly scored from 0 (nonvisible) to 2 (well visible) by two board-certified radiologists. The agreement between the two readers was assessed using Cohen's kappa statistics. Positive and negative vaginographies were compared using Wilcoxon tests. The agreement between readers varied between structures. A significant difference in grading was observed for the cervix, which was better visualized with positive vaginography (p-value = .0006), and the ostium of the urethra, which was more conspicuous on negative vaginography (p-value = .02). Both techniques offer similar visualization on most of the structures analyzed. Negative retrograde computed tomographic vaginography is a valuable and alternative technique to positive CT vaginography to assess the lower urogenital tract in female dogs.