Veterinary Radiology & Ultrasound最新文献

Since the prognosis of myxomatous mitral valve disease (MMVD) varies, its characterization is clinically relevant, and renal impairment has been identified as one of its associated factors. Intrarenal Doppler ultrasonography (IRD), an intrarenal hemodynamic assessment method, is useful for predicting cardiac- and renal-related death but cannot detect early changes in dogs with preclinical MMVD. Contrast-enhanced ultrasonography (CEUS), another intrarenal hemodynamic assessment method, may identify earlier changes; however, renal perfusion evaluations using CEUS have not yet been performed on dogs with MMVD. We hypothesized that CEUS detects changes earlier than IRD in dogs with preclinical MMVD. This prospective, cross-sectional study examined renal perfusion in dogs without cardiac disease and preclinical MMVD dogs of different American College of Veterinary Internal Medicine stages using CEUS and compared it with IRD indices. Twenty-three dogs with MMVD (ten stage B1 and thirteen stage B2) and 12 control dogs without cardiac disease were included. The rise times of the renal cortex and medulla were measured from a time-intensity curve. The rise time of the cortex was longer in dogs with stage B2 MMVD than in control dogs, while that of the medulla was shortened in the right ventricular dysfunction group in stage B2. No changes were observed in IRD indices (the resistance index and venous impedance index). In conclusion, CEUS detected changes in renal perfusion in dogs with preclinical MMVD even when IRD indices remained unchanged, suggesting the utility of CEUS in evaluations of renal perfusion in MMVD dogs.

The identification of a solitary splenic mass on abdominal ultrasound is a common occurrence; however, diagnosis based on imaging alone remains a challenge. Multiple studies have tried to identify key characteristics that denote a benign or malignant lesion before splenectomy. Differential diagnoses commonly include hemangiosarcoma, hematoma, extramedullary hematopoiesis, and lymphoid hyperplasia. While comprehensive, this list fails to consider the less frequent neoplasms such as splenic stromal sarcoma. This retrospective study aimed to evaluate 13 dogs diagnosed with canine splenic stromal sarcoma and determine common characteristics noted on abdominal ultrasound. Masses were solid, without evidence of cavitation, and arising from the mid-body of the spleen. While abdominal ultrasound does not provide a definitive diagnosis for splenic stromal sarcoma, it should be considered when identifying a solitary, solid, noncavitary splenic mass.

Radiotherapy (RT) for lung or liver tumors can be challenging due to respiration-induced organ motion (RIOM). There are some methodological solutions to minimize RIOM. We explored a new approach to evaluate the feasibility and reproducibility of RIOM during RT with five total client-owned tumor-bearing animals using a remote-triggered breath-hold ventilator under general anesthesia during image acquisition and RT. There was one stereotactic body radiotherapy, one conventionally fractionated definitive intent, and three conventionally fractionated palliative intent RT cases. Based on repeated cone beam CT, there were no treatment table shifts required prior to initiating beam on. No clinically significant complications such as hypotension occurred during anesthesia. This technique appeared to be safe in this group of patients and was easily clinically implemented and highly reproducible. More complete follow-up data and larger studies are needed to evaluate clinical outcomes with this breath-hold ventilator technique in veterinary RT.

The external jugular vein (EJV) has been commonly used for clinical procedures in veterinary medicine, while the internal jugular vein (IJV) has been used mainly for research. Limited literature regarding anatomical variants in both EJV and IJV is available. The objectives of this descriptive retrospective study were to identify the number of dogs with variations of the jugular veins in canine patients undergoing CT of the head and neck and characterize these variations. Of 1000 dogs, 193 dogs (19.3%) had anatomical variations. Six types of anatomical variations were identified. The most common Type I was the absence of the linguofacial vein (72.0%, n = 139), with the lingual, facial, and maxillary veins entering the EJV at a common branching point. Type II described a variable course of the EJV and IJV, which in some dogs resulted in the absence of the EJV (14.0%, n = 27). Type III was a variable anastomotic loop formed by the linguofacial or maxillary vein cranial or at the junction of the EJV (4.2%, n = 8). In Type IV, the EJV was either suspected to be aplastic or markedly reduced in diameter compared with the contralateral side just distal to its formation (3.6%, n = 7). Type V was found in only six dogs (3.1%) with unilateral differences in the diameter of the IJV. Six of 193 dogs had a combination of more than one variation (Type VI, 3.1%). Type I was significantly observed more frequently in meso- and dolichocephalic breeds. Type II was significantly observed more frequently in brachycephalic breeds.

Traumatic atlantoaxial hyperflexion is considered rare in cats, and only a few case reports have been published. There are other conditions that can result in a peracute onset of neurological signs localized to the cervical spinal cord segments, including acute noncompressive nucleus pulposus extrusion, ischemic myelopathy, or vertebral fractures. Appropriate treatment for these conditions can only be initiated after an accurate diagnosis has been obtained. The aim of this observational, retrospective, single-center, descriptive case series study was to describe the clinical presentation, imaging characteristics, and short-term outcome of eight cats presented with suspected traumatic atlantoaxial hyperflexion. Young male healthy domestic shorthair cats were overrepresented (7/8) and typically presented with a peracute, nonprogressive, nonpainful, nonlateralizing C1-C5 myelopathy (tetraplegia or nonambulatory tetraparesis) following a road traffic accident or head trauma. All MRI studies demonstrated a solitary, focal, ill-defined intramedullary lesion immediately dorsal to the dens of the axis, affecting both grey and white matter. All cats were treated medically. In 50% of the cats, the neurological grade improved at discharge or short-term follow-up, 25% of the cats recovered completely, one cat was static at short-term follow-up, and one cat was euthanized due to persistent forebrain signs and lack of neurological improvement.

Tympanokeratomas (cholesteatomas) are destructive keratinic masses of the middle ear that are often treated surgically. In humans, nonechoplanar (non-EP) diffusion-weighted (DW) MRI is efficient in diagnosing tympanokeratomas and differentiating recurrent tympanokeratomas from granulation or fibrous tissue after surgery. The objectives of this study were to (1) determine the characteristics of non-EP DWI of histologically or cytologically confirmed canine tympanokeratomas, (2) determine the performance of non-EP DW images, apparent diffusion coefficient (ADC) map and ADC values in discriminating between tympanokeratomas and other causes of otitis media in dogs, and (3) find an optimal ADC cut-off value. Medical records of dogs diagnosed on MRI with otitis media in two veterinary hospitals were retrospectively reviewed. Sixty-two ears with a cytological or pathological diagnosis of either tympanokeratoma (36/62) or nontympanokeratoma otitis media (26/62) were selected. Diffusion-weighted images had an accuracy of 77.4%, a sensitivity of 94.4%, and a specificity of 53.8% for the detection of tympanokeratoma. The ADC value of middle ear content ranged from 517 to 1355.10^-6 mm²/s in tympanokeratoma and from 454 to 2447 × 10^-6 mm²/s in nontympanokeratoma otitis media. An ADC value below 916 × 10^-6 mm²/s interpreted as a tympanokeratoma yielded an accuracy of 78.7%, a sensitivity of 92.6%, and a specificity of 60%. In the study population, combined qualitative analysis of DW images and ADC maps was the most effective method for diagnosing tympanokeratomas with an accuracy of 80.9%, a sensitivity of 92.6%, and a specificity of 65%.

MRI is widely used for the detection and characterization of brain lesions. There is a growing interest in the potential benefits of quantitative MRI (qMRI) in veterinary brain lesion diagnosis. Yet, the use of data processing tools in the veterinary field is not as democratized as for the diagnosis of human brain pathologies. Several reviews have addressed the characterization of brain lesions in cats and dogs. None of them is specifically focused on quantitative MRI data processing techniques for the diagnosis of brain lesions in the veterinary field. This paper aims to provide an overview of the evolution of qMRI on cats and dogs both in the clinical and preclinical fields. We analyze the achievements in the field as well as the remaining challenges in the diffusion of data processing tools for veterinary brain lesions characterization.

This pilot study presents initial experience obtained with a real-time predictive motion tracking platform called Synchrony mounted on the Radixact radiotherapy device. Synchrony radiotherapy treatments were offered as an alternative to surgical excision for primary pulmonary carcinomas as well as in dogs in a suspected oligometastatic disease state. All dogs were treated with three fractions of 8 Gy. Six dogs with pulmonary targets were successfully treated, while we were unable to treat abdominal targets with implanted fiducials. Cranial targets showed minimal movement, while targets located adjacent to the diaphragm showed a large amplitude of movement. No acute or late clinically apparent side effects were noted in any of the dogs that received radiation therapy. A strong partial response with minimal pneumonitis was seen in follow-up imaging of the one dog where imaging was available. Synchrony motion tracking will continue to be investigated for efficacy.

A 5-year-old spayed female Maltese was referred due to a suspected diaphragmatic hernia. Radiography revealed a soft tissue mass in the right caudal thorax with loss of diaphragm cupola dome-shape. A diaphragmatic hernia was considered, but surgical exploration revealed an intact diaphragm and unremarkable liver lobes. CT after a surgical inspection showed all intact liver lobes and intrathoracic mass connected to the liver. The intrathoracic mass was retracted to the abdomen by incising the diaphragm. Histopathologic examination revealed hepatocellular vacuolar degeneration, indicating an intrathoracic ectopic liver. Intrathoracic ectopic liver should be included in the differential diagnosis when diaphragmatic hernia is suspected in radiography.