Veterinary Radiology & Ultrasound最新文献

Cranial cruciate ligament (CCL) disease causes variable stifle instability assessed by specific clinical tests. Radiographs are performed to measure the tibial plateau angle (TPA) for planning tibial plateau leveling osteotomy (TPLO) surgery. Concomitant damage to other intra-articular structures, for which clinical detection is unreliable, may occur and potentially affect the surgical outcome. Joint assessment during TPLO through instrumented inspection is therefore advised, though it increases the risk of complications. Magnetic resonance imaging offers a noninvasive alternative, adds information about intra- and periarticular structures, and could potentially be used for TPA measurements. This prospective study aimed to (1) assess the correlation between the TPA measured with the standard presurgical radiographs and with a single sagittal intermediate-weighted fat-saturated MRI sequence and (2) compare the surgical findings with the information obtained by the MRI sequence. Twenty-one stifles were included; TPA correlation using radiographs-MRI was available for 17 stifles, and surgery-MRI comparison was available for 18 stifles. A strong significant correlation was identified between the TPA measurements on radiographs-MRI (Pearson correlation coefficient 0.923; p-value <.0001). The sensitivity and specificity of MRI to detect surgically confirmed complete versus partial CCL rupture were 85.7% and 75%, respectively; MRI identified 7 of 8 surgically confirmed injured menisci and detected abnormal signal intensity in 8 of 10 medial menisci and nine caudal cruciate ligaments reported as normal intra-operatively. The MRI additionally identified abnormal subchondral bone signals in nine stifles and muscular hyperintensity in six cases. This presurgical MRI sequence might replace standard radiographs for TPA measurements and can provide information about concomitant joint injuries with potential prognostic impact.

A case of two separate meningiomas with concurrent subdural fluid accumulation is presented. A 13-year-old, male neutered domestic shorthair cat presented with behavior change and progressive neurologic signs localizing to the forebrain. Two extra-axial masses were seen along with a large subdural fluid collection on advanced imaging of the brain. Histology of the lesions was consistent with multiple meningiomas, while analysis of the subdural fluid was consistent with cerebrospinal fluid. A case of multiple feline meningiomas with peritumoral subdural fluid accumulation has not previously been reported.

The effect of midline shift identified on brain MRI on survival time in dogs with structural brain disease is relatively unknown. This retrospective single-centered cohort study reviewed medical and imaging data of 77 dogs with structural brain lesions evident on MRI. Images were reviewed for the presence of midline shift, brain edema, foramen magnum herniation, and ventriculomegaly. Kaplan-Meier method and Cox regression analysis were undertaken to compare survival between dogs with and without midline shift. Midline shift was present in 40 of 77 (52%) dogs and absent in 37 of 77 (48%). Univariate analysis revealed that dogs with midline shift had a median survival time of 34.5 days (95% CI, 4-108 days) compared with 241 days (95% CI, 133,- days) in dogs without midline shift (hazard ratio = 2.67, 95% CI, 1.5-4.49). Multivariate Cox regression analysis revealed a hazard ratio of 3.6 (95% CI, 1.7-7.6; P-value < .001) for dogs with midline shift. Shorter median survival times remained significant in all groups after segregation based on etiological diagnosis. The significantly shorter survival times observed herein for dogs with midline shifts, regardless of etiologic cause, provide further evidence that midline shift holds value as a negative prognostic factor in diagnostic imaging.

This case report refers to a 1-year-old Guinea pig showing signs of anorexia and antipain posture. On abdominal radiography, five rounded mineral opaque structures were evident in the mid-caudal abdomen. On ultrasound, a right seminal vesicle with a reduction in diameter was observed, containing less echogenic material than the contralateral one, with five oval structures with a hyperechogenic contour and a central hypoechogenic area, forming acoustic shadowing. The left seminal vesicle presented with the usual characteristics. After bilateral vesiculectomy, the patient recovered well, with no further symptoms. The histopathological result was a suppurative/abscessive inflammatory process with an accumulation of proteinaceous material.

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.

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.