首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 160 毫秒
1.
Survey radiography, linear tomography, and computed tomography were used to image cribriform plate lesions that were created experimentally using intramedullary pins in 18 dog cadaver skulls. Computed and linear tomographic images were taken along the dorsal imaging plane. Studies were independently reviewed by five observers. Results were combined so that the relative sensitivity, specificity, and accuracy of each imaging technique could be compared using chi-square analysis. Computed tomography proved to be significantly more sensitive and accurate (p<0.05) than either linear tomography or survey radiography. Computed tomographic images were consistently of good to excellent quality for imaging the cribriform plate. It was concluded that computed tomography of the skull using a dorsal imaging plane was the best available imaging modality for detecting 3-mm and 5-mm experimentally created cribriform plate defects.  相似文献   

2.
The radiographic appearance of the cribriform plate was investigated in 16 canine cadaver heads. The cribriform plate appeared as a "V"-shaped multilinear bone-opaque stripe in the caudal nasal region in projections perpendicular to the hard palate in 6 dogs with a skull index between 50.00 and 54.00. In 9 dogs with a skull index between 55.40 and 74.40, the cribriform plate had a more "C"-shaped and sharp appearance. In vertically oblique projections with an obliquity greater than 20 degrees, the cribriform plate lost its sharp outline and finally (40 degrees) disappeared. In lateral projections the cribriform plate appeared as a "C"-shaped interrupted bone-opaque stripe in all 16 dogs. In more brachycephalic dogs frontal bone structures superimposed on the cribriform plate on ventrodorsal and dorsoventral views and accentuated the radiographic appearance of the plate. Vertically oblique views separated both structures to produce two lines.  相似文献   

3.
Computed tomography (CT) was used to study the normal anatomy of the orbital region in one Beagle. Direct transverse and reformatted dorsal, sagittal, and oblique plane images were used to distinguish various soft tissue structures. Intraorbital fat provided a natural contrast against which extraocular muscles and nerves could be discerned. The noninvasive nature and the multiplanar imaging capabilities of CT provided a means by which the orbital contents could be precisely localized and differentiated from one another.  相似文献   

4.
5.
Computed tomographic (CT) imaging of eight normal cadaveric canine stifles was performed before and after intra-articular administration of iodinated contrast medium. Transverse CT images were reconstructed in dorsal, parasagittal, and oblique planes. The following ligamentous structures were identified on transverse CT images in all stifles: cranial cruciate ligament, caudal cruciate ligament, medial meniscus, lateral meniscus, and the medial and lateral collateral ligaments. The following ligamentous structures were identified on transverse computed tomographic arthrography (CTA) images in all stifles: cranial cruciate ligament, caudal cruciate ligament, medial meniscus, lateral meniscus, meniscofemoral ligament, cranial meniscotibial ligaments, caudal meniscotibial ligaments, intermeniscal (transverse) ligament, and the medial and lateral collateral ligaments. The patellar tendon was identified on transverse and reconstructed dorsal and sagittal CT and CTA images in all stifles. Multiplanar reconstructions enabled further evaluation of the continuity of the cranial and caudal cruciate ligaments and menisci. The medial and lateral collateral ligaments were not clearly identified on CT or CTA multiplanar reconstructed images.  相似文献   

6.
This study describes a detailed computed tomographic reference of the normal equine foot. Ten forefeet of five adult cadavers, without evidence of orthopaedic disease, were used. Computed tomography (CT) was performed on all feet. Two‐millimetre thick transverse slices were obtained, and sagittal and dorsal planes were reformatted. The CT images were matched with the corresponding anatomic slices. The phalanges and the distal sesamoid bone showed excellent detail. The extensor and flexor tendons (including their attachments) could be clearly evaluated. The collateral (sesamoidean) ligaments could be readily located, but were difficult to delineate at their proximal attachment. The distal digital annular ligament could only be distinguished from the deep digital flexor tendon proximal to the distal sesamoid bone, and its proximal attachment could be identified, but not its distal insertion. Small ligaments (impar ligament, chondrosesamoidean, chondrocoronal and chondrocompedal ligaments, axial and abaxial palmar ligaments of the proximal inter‐phalangeal joint) were seen with difficulty and not at all slices. The joint capsules could not be delineated from the surrounding soft tissue structures. The lateral and medial proprius palmar digital artery and vein could be visualized occasionally on some slices. The ungular cartilages, corium and hoof wall layering were seen. The nerves, the articular and fibrocartilage of the distal sesamoid bone and the chondroungular ligament could not be assessed. Computed tomography of the equine foot can be of great value when results of radiography and ultrasonography are inconclusive. Images obtained in this study may serve as reference for CT of the equine foot.  相似文献   

7.
The objective of this study was to provide a detailed multiplanar computed tomographic (CT) anatomic reference for the bovine tarsus. The tarsal regions from twelve healthy adult cow cadavers were scanned in both soft and bone windows via a 16‐slice multidetector CT scanner. Tarsi were frozen at ?20o C and sectioned to 10‐mm‐thick slices in transverse, dorsal and sagittal planes respecting the imaging protocol. The frozen sections were cleaned and then photographed. Anatomic structures were identified, labelled and compared with the corresponding CT images. The sagittal plane was indispensable for evaluation of bone contours, the dorsal plane was valuable in examination of the collateral ligaments, and both were beneficial for assessment of the tarsal joint articulations. CT images allowed excellent delineation between the cortex and medulla of bones, and the trabecular structure was clearly depicted. The tarsal soft tissues showed variable shades of grey, and the synovial fluid was the lowest attenuated structure. This study provided full assessment of the clinically relevant anatomic structures of the bovine tarsal joint. This technique may be of value when results from other diagnostic imaging techniques are indecisive. Images presented in this study should serve as a basic CT reference and assist in the interpretation of various bovine tarsal pathology.  相似文献   

8.
Our objectives were to establish a magnetic resonance (MR) protocol for the examination of, and then describe, the normal ligaments and the supporting structures of the occipitoatlantoaxial region. This was done in 10 cadaver dogs. In addition, MR images of three patients with cervical pain localized to the occipitoatlantoaxial region are included to provide examples of ligamentous abnormalities. All ligaments were hypointense in all pulse sequences. The apical, dorsal atlantoaxial, and dorsal longitudinal vertebral ligaments were seen best in the sagittal T1W and PD-weighted images. The transverse ligament was best visualized in the transverse plane in all pulse sequences and appeared to be confluent with the dorsal longitudinal vertebral ligament dorsal to the dens in the sagittal plane. A 20° dorsal plane reconstructed image in 0.6-mm slice thickness was necessary to visualize the alar ligaments, which were visible in 9/10 dogs. The dorsal longitudinal vertebral ligament appeared continuous with the apical ligament and tectorial membrane. Abnormalities in clinically affected dogs included thickening of the alar ligaments, absence of transverse ligament and elongation, and irregularity of the apical ligament.  相似文献   

9.
The vascular anatomy of the ethmoidal area in six normal horses and two normal ponies was studied using vascularcorrosion casts. The major arterial supply to the ethmoidal area sterns from an intracranial source. The internal and external ethmoidal arteries anastomose on the rostral intracranial surface of the cribriform plate to form the arterial ethmoidal rete which arborizes and passes through the perforations of the cribriform plate to supply the ethmoid labyrinth. A minor arterial supply to the ventral portion of the ethmoid labyrinth sterns from a small caudal nasal branch of the sphenopalatine artery. Multiple parallel venules drain the ethmoid labyrinth rostrally to its apex then join the venous drainage from the surrounding sinuses.  相似文献   

10.
Computed tomographic arthrography (CTA) of four cadaveric canine stifles was performed before and after partial cranial cruciate ligament rupture in order to verify the usefulness of CTA examination for the diagnosis of partial cranial cruciate ligament rupture. To obtain the sequential true transverse image of a cranial cruciate ligament, the computed tomography gantry was angled such that the scanning plane was parallel to the fibula. True transverse images of cranial cruciate ligaments were identified on every sequential image, beginning just proximal to the origin of the cranial cruciate ligament distal to the tibial attachment, after the administration of iodinated contrast medium. A significant decrease in the area of the cranial cruciate ligament was identified on CTA imaging after partial surgical rupture of the cranial cruciate ligament. This finding implies that CTA can be used for assessing partial cranial cruciate ligament ruptures in dogs.  相似文献   

11.
The purpose of this study was to provide a detailed computed tomographic (CT) anatomic reference for the equine tarsus. CT examinations of the tarsal regions from four clinically and radiographically normal adult horses, which were euthanized for reasons not related to musculoskeletal disease, were included in the study. Limbs were removed at the level of midtibia, and 3-mm contiguous transverse CT images were obtained, starting at a level proximal to the tuber calcanei and continuing distally into the proximal metatarsus. Soft tissue and bone windows were used to image different anatomic features, including bones, joints, and various soft tissue components of the tarsus. Each transverse slice was compared with bone models and dissected specimens to assist in the accurate identification of specific structures. The results of the study consist of nine CT images of the equine tarsus. Each image incorporates labeled soft tissue and bone-window images, a directional compass indicating cranial (Cr) or dorsal (D) and lateral (L), and a reconstructed scout image indicating the level through which the transverse slice was made.  相似文献   

12.
Fungal infections affecting the central nervous system are rare. The purpose of this study was to describe clinical and imaging findings in dogs with intracranial blastomycosis (Blastomyces dermatiditis). The radiology database was searched retrospectively for patients with a diagnosis of intracranial blastomycosis which had computed tomography performed as part of their diagnostic work-up. Medical records and imaging studies were reviewed. Five dogs met the inclusion criteria. Major presenting complaints were stertor/nasal discharge (n=2), exophthalmos (n=1), and seizures (n=2). Clinical and laboratory findings were variable. Computed tomographic examination revealed a single contrast-enhancing intra-axial mass (n=1), a nasal mass disrupting the cribriform plate (n=3), and an intracranial mass extending into the orbit and nasal cavity (n=1). Findings in intracranial blastomycosis in dogs are variable, and the disease may mimic other inflammatory disorders or neoplasia.  相似文献   

13.
An 11‐year‐old Warmblood gelding with chronic bilateral epistaxis was diagnosed with an adenocarcinoma of the right ethmoid, based on transendoscopic biopsy. On computed tomography images, the cribriform plate was considered intact and the tumour was minimally invasive in surrounding tissue. The palliative treatment included a combination of surgical exploration and laser ablation. Following recurrence of the clinical signs one month later, intralesional formalin injection was performed. In the immediate post injection period, the horse developed severe neurological signs. Because of the overall poor prognosis, the horse was subjected to euthanasia. On post mortem examination, changes were seen in the frontal lobe consistent with diffusion of formalin through the cribriform plate. Care is needed when treating horses with intralesional formalin because macroscopic appearance of the cribriform plate may not relate to its functionality.  相似文献   

14.
This study uses computed tomography and computer aided design software (I-DEAS(tm)) for the development of a three-dimensional electronic solids model of the lower limb of the horse. Data from two millimeter transverse contiguous slices of the distal forelimb of a yearling horse were acquired from a computed tomographic scanner and then transferred to a computer system via magnetic tape. Outline of the bony tissue for each scan slice was first obtained with a feature extraction algorithm. A solids model for each skeletal segment of the specimen was then reconstructed with I-DEAS(tm) and subsequently displayed with various graphics options. The reconstructed electronic solids model would be useful for the study of 3D joint mechanics and finite element analysis of the bony structures, as well as for diagnostic purposes providing CT images could be obtained antemortem.  相似文献   

15.
An anatomic study of the equine digit using magnetic resonance imaging (MRI) was performed. Seventeen isolated forelimbs and one hindleg of nine warmblood horses were imaged in transverse, sagittal, and dorsal planes with a 1.5 Tesla magnet using T1-, T2- proton density-weighted spin echo sequences as well as T2 gradient echo sequences. One scan plane in each horse was compared with corresponding anatomic and histologic sections. The best imaging planes to visualize various anatomic structures were determined. Fibrocartilage was visualized in the insertion of the deep digital flexor tendon and the suspensory ligament as well as in the distal sesamoidean ligaments. The correlation of MRI images with anatomic and histologic sections confirmed that all of the anatomic structures in the equine digit could be evaluated in PD and T2 studies.  相似文献   

16.
17.
The aim of this study was to develop an anatomical model of the feline hip joint for low‐field magnetic resonance imaging (LF‐MRI) based on high‐field magnetic resonance imaging (HF‐MRI). The study was performed on six adult clinically healthy European shorthair cats, aged 1–3 years, with body weight of 2.8–4.4 kg. The animals were examined with the use of the Vet‐MRI Grande Esaote LF (0.25 T) scanner and high‐field Siemens Magnetom TRIO (3 T) MRI scanner. In the LF‐MRI, most satisfactory results in T1‐weighted images were obtained when TE was 26 ms in all three planes and when TR was 350–950 ms in the transverse plane, 950–1150 ms in the sagittal plane and 520–750 ms in the dorsal plane. In T2‐weighted images, TE was 90 ms in the transverse and dorsal plane and 120 ms in the sagittal plane. The results were presented as images acquired with LF‐MRI scanners in three planes. The slice thickness was 3 mm for each plane. In LF‐MRI, muscles in the hip joint region and round ligament were well visualized. Unlike in LF‐MRI, the cross section of the femoral nerve was identified in HF‐MRI scans. In examinations of the feline hip joint, the main limitations of LF‐MRI were a lack of reliable contrast between articular cartilage and synovial fluid as well as longer scan time. Despite the above, LF‐MRI images were characterized by good contrast between bones and the surrounding soft tissues.  相似文献   

18.
The elbow     
Computed tomography (CT) and magnetic resonance imaging (MRI) are noninvasive methods of imaging the canine cubital joint. CT images are typically acquired using contiguous 1-mm slices, a bone reconstruction algorithm, and a field of view large enough to scan both elbows simultaneously. CT provides a detailed assessment of the medial coronoid process (MCP), radial incisure, anconeal process, and trochlear notch of the ulna; the humeral condyle; joint congruity; and osteoarthrosis. With MRI, use of a surface coil and 3D Fourier transformation gradient echo fast imaging sequences allow contiguous thin slices to be obtained. Both imaging techniques appear to be highly effective in the evaluation of elbow dysplasia, particularly for the detection of MCP fragmentation, although MRI is superior to CT for identifying nonmineralized cartilaginous fragments.  相似文献   

19.
Computed tomography (CT) uses x‐ray beams and reconstructive computer technology to create tomographic slices (sections) of the area being imaged. Computed tomography has higher contrast resolution than conventional radiography allowing for more accurate differentiation of soft tissues and fluids. This form of 3D imaging removes problems caused by superimposition of multiple anatomical structures, which is a major impediment when viewing radiographs of the equine head. Once the images are acquired, multi‐planar and 3D reconstructions can be performed to view different teeth or associated structures in an optimal way. Anatomical and pathological changes in the dental tissues, periodontal tissues, alveolar bone and adjacent sinuses can then be assessed. Scintigraphy with 99m technetium methyl‐diphosphate (methylene‐diphosphonate) can detect changes in bone that precede radiographic changes, and this makes it a very useful imaging modality for diagnosis of early periapical infection of the equine cheek teeth. Additionally, it is invaluable for imaging suspected infections of supernumerary or dysplastic teeth where the results of radiography or even CT may be equivocal. Periapical infections of the cheek teeth typically result in focal and intense increased radionuclide uptake located over the apical region of the affected tooth.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号