排序方式： 共有15条查询结果，搜索用时 562 毫秒
11.
GABRIELA S. SEILER IAN D. ROBERTSON SRINIVASAN MUKUNDAN DONALD E. THRALL 《Veterinary radiology & ultrasound》2011,52(3):313-316
Pulsatile venous flow in the internal vertebral venous plexus of the cervical spine can lead to vertical, linear T2‐hyperintensities in the spinal cord at the cranial aspect of C3 and C4 in transverse T2‐weighted images in large breed dogs that are not accompanied by ghosting. The artifact is more conspicuous in pre‐ and postcontrast transverse T1‐weighted images and is accompanied by ghosting in that sequence, typical of a pulsatility artifact. A flow‐related artifact was confirmed as the cause for this appearance by noting its absence after either exchange of phase and frequency encoding direction or by flow compensation. Care should be exercised to avoid misdiagnosing this pulsatility artifact seen in transverse T2‐weighted images of the midcervical spine in large dogs as an intramedullary lesion when T1‐images or phase‐swap images are not available to confirm its artifactual origin. 相似文献
12.
Ultrasonography (US) and computed tomography (CT) were performed after routine ophthalmologic and ophthalmoscopic examinations in 190 eyes of six various diurnal (common buzzard [Buteo buteo L., 1758], n = 20; common kestrel [Tinnunculus tinnunculus L., 1758], n = 20) and nocturnal raptor species (barn owl [Tyto alba L., 1758], n = 22; tawny owl [Strix aluco L., 1758], n = 8; long-eared owl [Asio otus L., 1758], n = 5; horned owl [Bubo bubo L., 1758], n = 1); and domestic pigeons (Columba livia, Gmel., 1789; n = 19), with a total of 95 individuals. Pathologic findings such as lens subluxation and luxation, intravitreal hemorrhage, detached retina, post-traumatic partial sequestration, or malformation of the pecten could be demonstrated with diagnostic imaging tools, while opacities of cornea or lens constrained direct ophthalmoscopic examination. The results proved US to be a quick noninvasive imaging technique for detailed ocular diagnoses. CT provided detailed information of the bony skull and bony scleral rings as well as adequate visualization of shape, size, and margination of the eye and lens. Nevertheless, CT was unable to differentiate subtle structures within the vitreous like the pecten oculi or hemorrhage. Biometric measurements were carried out to objectify imaging results. Results showed good correlation of depth and width of the anterior eye chamber, lens and vitreous, length of the bulbus, and the pecten but no correlation of cornea and posterior wall thickness was found. 相似文献
13.
GABRIELA S. SEILER THOMAS J. NOLAN ELEANOR WITHNALL CARYN REYNOLDS JAMES B. LOK MEG M. SLEEPER 《Veterinary radiology & ultrasound》2010,51(2):136-140
Evolution of pulmonary arterial and parenchymal changes as assessed with computed tomography (CT) is described in a dog experimentally infected with Dirofilaria immitis. The dog was imaged 125, 168, 216, and 402 days after infection. Initial changes during the prepatent phase of infection included enlargement of the peripheral caudal lobar pulmonary arteries and intermittent periarterial interstitial infiltrates. The changes were progressive, involving additional arteries over time, but remained mild. With the presence of adult filariae a filling defect was observed in the caudal lobar pulmonary artery using CT angiography. Recognizing thoracic CT findings associated with the prepatent phase of canine heartworm infection may be important in endemic areas. 相似文献
14.
JENNIFER KINNS WILFRIED MAI GABRIELA SEILER ALLISON ZWINGENBERGER VICTORIA JOHNSON ANA CÁCERES ALEJANDRO VALDÉS-MARTÍNEZ TOBIAS SCHWARZ 《Veterinary radiology & ultrasound》2006,47(6):563-570
The objectives of this study were to establish the sensitivity and negative predictive value of radiography for acute spinal osseous lesions in the canine trauma patient, and to evaluate the interobserver variability in radiographic assessment of the spine in traumatized dogs. This was a retrospective multiple observer blinded study. The study population included 30 canine patients that presented following acute trauma, with clinical signs attributable to the spinal column. Radiography and computed tomography (CT) were performed in all cases. Radiographic interpretation was performed independently by four observers with different experience levels who were blinded to clinical information (other than trauma) and the CT results. CT studies were interpreted by a further three radiologists who formed a consensus opinion on the presence of specific osseous lesions. Using the CT results as a gold standard, the sensitivities and negative predictive values of radiography for specific osseous lesions were calculated. Interobserver agreement was also evaluated. Radiography was found to have only a moderate sensitivity for fractures (72%) and subluxations (77.5%). Low negative predictive values were found for the presence of vertebral canal narrowing (58%) and fracture fragments within the vertebral canal (51%). Interobserver agreement was only moderate to fair for most lesion types. In conclusion, radiography cannot be used to reliably rule out potentially unstable acute vertebral lesions in the canine trauma patient, and further imaging is therefore often indicated in the patient with a high risk of such injuries. 相似文献
15.
GABRIELA SEILER TOBIAS SCHWARZ MASSIMO VIGNOLI DANIEL RODRIGUEZ 《Veterinary radiology & ultrasound》2008,49(6):504-508
The imaging features of lung lobe torsion in 10 dogs (nine complete, one partial torsion) acquired with a helical single‐slice computed tomography (CT) unit are described. Attenuation values of normal, rotated, and adjacent collapsed lung lobes before and after intravenous contrast medium administration were compared. Affected lung lobes were: left cranial (5), right middle (3), right cranial (1), and left caudal (1). CT findings in nine dogs with complete lung lobe torsion included pleural effusion and an abruptly ending bronchus. In eight of these dogs, enlargement, consolidation, emphysema of the affected lung lobe, and mediastinal shift to the contralateral side were present. Rotated lung lobes did not enhance, whereas adjacent collapsed and aerated lung lobes did (P<0.05). Apnea induced with hyperventilation or breath‐hold is essential to reduce motion artefacts and obtain a diagnostic study. 相似文献