Veterinary Radiology & Ultrasound最新文献

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.

This study aimed to evaluate the use of acoustic radiation force impulse (ARFI) elastography as a diagnostic tool for lung lesions in dogs. Dogs referred to the Radiology Department of the Veterinary Teaching Hospital between 2020 and 2022 for the detection of lung lesions were included in the study. The characteristics of the lung lesions were assessed using radiography as a screening tool for localization, B-mode ultrasound for tissue characterization, and subsequently, both qualitative (elastogram grades 1-3) and quantitative (shear wave velocity-SWV) elastographic evaluations. The lesions were classified based on clinical, ultrasound, radiographic, histopathological, and/or cytological findings into the following categories: consolidations, atelectasis, or neoplasms (nodules and masses). Twenty-six dogs met the eligibility criteria and were included in the study. In some cases, the same dog had more than one type of lesion, resulting in the evaluation of 35 lung lesions: 13 masses, 8 nodules, 8 consolidations, and 4 areas of atelectasis. The quantitative elastographic evaluation revealed lower stiffness in atelectatic lesions (1.48 ± 0.35 m/s) compared with consolidations (2.94 ± 0.64 m/s), nodules (2.85 ± 1.40 m/s), and masses (3.13 ± 1.45 m/s), although no definitive diagnostic cut-off value was established, due to the limited number of benign lesions. The results suggest that ARFI elastography can be a valuable complementary tool alongside clinical data and conventional imaging techniques in assessing lung lesions in dogs. Future studies with a larger sample size of benign parenchymal lung lesions are needed to further explore the potential of elastography for predicting malignancy.

Vicarious excretion is a nonrenal pathway of excretion for intravenously injected iodinated contrast media, with a limited understanding of its influencing factors and imaging features. In this prospective pilot study, gallbladder opacification (GBO) and small intestinal luminal opacification (SILO) were assessed to identify vicarious excretion patterns following intravenous contrast media administration for CT in clinically healthy dogs. Eight beagles were studied using a crossover method, divided into fed and fasted groups. The fed group was fed at 5 and 13 h after the first CT scan, while the fasted group was fed only at 13 h. Noncontrast and postcontrast CT scans were performed at 90 s, 10 min, 1 h, 4 h, 12 h, and 24 h after iohexol injection. The GBO was subjectively scored from grade 0 to 5 based on the attenuation value and area of opacification. The SILO was evaluated subjectively based on contrast intensity (weak or marked) and distribution. The GBO was observed from 1 h after contrast injection. Significant differences were noted in median GBO scores within the groups at 4, 12, and 24 h on Friedman's test followed by the post hoc Wilcoxon signed-rank test. The scores were significantly higher in the fasted group at 12 h on the Wilcoxon signed-rank test. The SILO occurred 10 min after contrast administration, with various distributions. In conclusion, GBO and SILO can be observed during delayed CT phases, and fasting increases the intensity and duration of GBO in clinically healthy dogs. These findings should not be interpreted as pathological changes.

In canines with primary hyperparathyroidism, preoperative imaging is recommended to identify abnormal parathyroid glands. However, imaging modalities have been reported to have up to a 19% discrepancy with surgical findings. This study aimed to evaluate the agreement between cervical CT and surgical findings in diagnosing primary hyperparathyroidism. Twenty client-owned dogs with suspected primary hyperparathyroidism were enrolled. Each dog underwent a cervical CT scan under sedation or anesthesia that was interpreted by a board-certified radiologist. Subsequently, all dogs underwent bilateral cervical exploration by a board-certified surgeon or a residency-trained surgery clinician. The laterality, position, and size of suspected parathyroid nodules were recorded from both CT and surgery. Agreement between the two methods was assessed using Cohen's kappa statistic for laterality and position, and Lin's concordance correlation coefficient (CCC) for size. Results showed near-perfect agreement for laterality (κ = 0.81) and position (κ = 0.92), but only fair agreement for gland size (CCC = 0.38). Additionally, in five cases, pathologic parathyroid or thyroid tissue was removed during surgery that was not identified on CT. These findings suggest that while CT provides better agreement than ultrasound for certain aspects of parathyroid pathology, continued bilateral cervical exploration remains essential for accurate diagnosis and treatment.

A 9-year-old male neutered Labrador Retriever was referred for azotemia and bilateral renomegaly. An abdominal ultrasound revealed severe bilateral renomegaly with septated subcapsular cystic anechoic lesions, consistent with renal lymphangiectasia. Despite conservative management, the patient died. Necropsy and histopathology confirmed dilated subcapsular vascular structures. Renal lymphangiectasia is a rare, benign dilation of renal lymphatics previously reported in human medicine. This case represents the first description of sonographic features of renal lymphangiectasia in a canine patient.

A 10-year-old neutered male domestic shorthair cat presented with acute lethargy, dysorexia, and a single episode of vomiting. Abdominal ultrasound revealed an anomalous and slightly tortuous course of the caudal vena cava (CdVC), just cranial to the junction of the renal veins. Thoracic radiographs showed an abnormally enlarged azygos vein. CT showed the absence of the prehepatic CdVC segment, with postrenal caval blood being shunted to a distended right azygos vein. Segmental CdVC aplasia should be considered in the evaluation of abdominal vascular anomalies in cats, particularly on CT angiography.

A 9-month-old male entire flat-coated retriever was referred for investigation of chronic right pelvic limb lameness following trauma. Radiographs and contrast-enhanced CT confirmed a right femoral head Salter-Harris type III fracture with monostotic metaphyseal mixed-type lysis and joint effusion. An aggressive process due to underlying neoplasia or infection with secondary pathological fracture could not be excluded. The dog underwent surgical bone biopsy and, consequently, right femoral head and neck ostectomy (FHO). Histopathology described retained cartilage cores within the trabecular bone of the metaphysis and periosteal resorption in the right femoral head and neck, with no signs of inflammation or malignancy.

Failure of fixation is a potential complication associated with surgical implants, and early detection is important but challenging. Positron emission tomography (PET) has the potential to detect lesions that may exhibit little to no visible findings on other commonly used diagnostic imaging modalities. The aim of this retrospective descriptive study was to assess ¹⁸F-Sodium Fluoride (¹⁸F-NaF) uptake associated with surgical implants in dogs. Medical records were searched for canine patients with orthopedic metallic implants in place imaged with ¹⁸F-NaF PET/CT. PET images were reviewed blinded to clinical history, with each surgical implant assessed for the presence of increased radiopharmaceutical uptake (IRU). IRU was graded subjectively regarding the severity (absent, mild, moderate, severe) and the extent area (focal, multifocal, extensive), and objectively by measuring maximal standardized uptake values (SUVmax). Seven patients were included, with a total of 39 metallic implants used in eight surgical procedures (three total hip replacements, three humeral fractures, one tibial plateau leveling osteotomy, and one tibial tuberosity advancement). In 24 of 39 implants (62%), no IRU was displayed. Fifteen implants (38%) displayed IRU (five mild, five moderate, five severe). The highest SUVmax (24) was associated with confirmed sepsis of a total hip replacement implant. The remaining implants with severe IRU were articular implants with associated marked degenerative joint pathology. This study confirms that most implants displayed no IRU with ¹⁸F-NaF PET. The presence of implant-associated IRU may indicate implant failure; however, IRU may also be due to regional bone pathology, including both degenerative joint disease and sepsis.

Radiographic examination of the skull is a well-established and indispensable procedure for the diagnostic evaluation of dental and paranasal sinus disorders in horses. Complementary projections make significant contributions to radiographic diagnosis in nasal conchae disorders. This article describes a complementary radiographic projection designed for the evaluation of the conchal sinuses and bullae in horses. Six equine cadaveric heads were used. Specimens were dissected, and openings were created in the ventral and dorsal nasal conchae for the introduction of radiopaque material. The new radiographic projection was named lateral 75° dorsal-lateral ventral oblique view. This projection was obtained with the mandibular rami resting on the imaging plate and the mandible displaced toward the side of interest (partial excursion). The X-ray beam was directed dorsoventrally, slightly angled toward the side of interest (left or right offset mandible dorsoventral view), and centered at an imaginary line connecting the tips of the facial crests. The lateral 75° dorsal-lateral ventral oblique view provided enhanced visualization and allowed correct identification of equine conchal structures. Lateral displacement of the mandible and the 75° angle of inclination to the vertical plane eliminated the superimposition of anatomical structures, facilitating radiographic image interpretation and increasing diagnostic accuracy. This complementary projection is recommended in all cases of sinonasal disorders in horses.

Pentastomids are parasites of the respiratory system of reptiles, birds, and mammals, where they can cause lesions resulting in the death of their intermediate hosts. This report describes radiographic aspects of pulmonary pentastomid infection in the Southern American bushmaster (Lachesis rhombeata). A female juvenile snake rescued in an urban area of the Northeast region of Brazil presented with lethargic behavior. Radiographic examination of the coelom cavity showed long cylindrical structures in the respiratory system with soft tissue radiodensity and width ranging between 4.0 and 5.0 mm. The next day, the snake died and was submitted to necropsy, where lung parasites were discovered, which were later identified as Porocephalus stilesi. A case of correlation between radiographic and macroscopic findings of pentastomid in snakes has not previously been reported.