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1.
Ten dogs with primary (n = 8) and metastatic (n = 2) brain tumours were studied in an attempt to evaluate the diagnostic sensitivity of computed tomography (CT) or magnetic resonance imaging (MRI). Of the clinical signs noticed, seizures (seven of 10), behavioural abnormalities and cognition dysfunction (seven of 10), compulsive walking and circling (six of 10), sensorimotor (five of 10) and neuro-opthalmological (two of 10) dysfunction were the most common. In all 10 animals that finally died of the disease or were killed, the histopathological diagnosis that followed necropsy was taken as a golden standard in the CT or MRI prediction of the histological type of brain neoplasms. In every instance, tumour detection, morphology and histological differentiation were possible with the aid of either CT (seven of 10) or MRI (three of 10) imaging especially after contrast enhancement. Only one CT-evaluated dog, diagnosed as meningioma, was found to be astrocytoma on histopathology. Interestingly, a rare case of cerebellar medulloblastoma was correctly identified in MRI scans.  相似文献   

2.
The recent application of neuroimaging techniques in veterinary neurology has led to the accurate localization of many types of intracranial lesions but has also created a clinical need, particularly with brain tumors, for a specific intraoperative diagnosis. For human brain tumors, a smear technique has been used successfully for many years to provide an extremely rapid, highly accurate intraoperative diagnosis. In similar smear preparations of intracranial lesions, obtained either by computed tomography (CT)-guided stereobiopsy or from a craniotomy, we have described distinguishing cytologic features of some primary spontaneous nervous system tumors in 80 dogs and 13 cats. A final diagnosis was confirmed by evaluation of paraffin-embedded sections from the same sample and, when appropriate, by immunocytochemical staining. Preliminary findings indicate that, in dogs and cats, this procedure is useful for rapid, accurate intraoperative diagnosis of many primary nervous system tumors. The distinguishing features of the canine and feline tumors bear a remarkably close resemblance to their human counterparts.  相似文献   

3.
OBJECTIVE: To validate mutual information criterion as a ready-to-use technique for automated alignment (ie, registration) of 3-dimensional (3-D) multimodal image data of the head of cats and dogs. SAMPLE POPULATION: Corresponding 3-D magnetic resonance imaging (MRI) and computed tomography (CT) brain scans of a 6-month-old Doberman Pinscher with a brain cyst; CT images of the head of a European shorthair cat with a meningioma before and immediately, 3, and 6 months after surgical resection; and CT and corresponding stacked anatomic cryosection images of the entire head of a 2-year-old sexually intact female Beagle. PROCEDURE: All images were matched retrospectively by use of an in-house computer program developed on the basis of a mutual information image registration algorithm. Accuracy of the resulting registrations was evaluated by visual inspection. RESULTS: All registrations were judged to be highly accurate. Additional manual corrections were not necessary. CONCLUSIONS AND CLINICAL RELEVANCE: Mutual information registration criterion can by applied to 3-D multimodal head images of cats and dogs for full automatic rigid-body image registration. The combination of such aligned images would considerably facilitate efforts of veterinary clinicians as indicated by its widespread use in brain surgery and radiation therapy of humans.  相似文献   

4.
THE DURAL TAIL SIGN IN THE DIAGNOSIS OF MENINGIOMAS   总被引：3，自引：0，他引：3  
John P.  Graham  MVB  MSc  Susan M.  Newell  DVM  MS  Andra K.  Voges  DVM  Gregory D.  Roberts  DVM  MS  Jay M.  Harrison  MS 《Veterinary radiology & ultrasound》1998,39(4):297-302
In humans the dural tail is a sign seen on contrast enhanced T1 weighted magnetic resonance images. This finding is considered specific for meningioma. The purpose of this study was to determine how often the dural tail occurs in cats and dogs and whether it is a specific sign for meningiomas in these species. MR examinations for eighteen dogs and four cats with proven diagnoses were reviewed. Diagnoses included ten meningiomas (seven dogs and three cats), three gliomas, two pituitary tumors, single examples of two other tumor types and five patients with mass lesions due to inflammatory disease. Contrast enhanced T1 weighted images were evaluated independently by three of the authors for the presence of a dural tail, without knowledge of the diagnoses. The results were compared to the diagnosis for each patient and the performance of individual reviewers compared. When their results were averaged, the reviewers reported the presence of a dural tail in 6 of 10 (60%) meningiomas, although detection varied between observers from 40% to 80%. Each reviewer had one false positive result, two reported a dural tail with a chromophobe adenocarcinoma and one with a toxoplasma meningoencephalitis. When a dural tail is seen an associated mass is most likely a meningioma. It is uncertain whether the dural tail represents neoplastic infiltration beyond the margins of the meningioma. This should be considered when planning treatment.  相似文献   

5.
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6.
Objective To describe the ophthalmologic, neurologic, and magnetic resonance imaging (MRI) findings of seven animals with acute postretinal blindness as sole neurologic deficit. Methods Medical records were reviewed to identify dogs and cats with postretinal blindness of acute presentation, that had a cranial MRI performed as part of the diagnostic workup. Only animals lacking other neurologic signs at presentation were included. Complete physical, ophthalmic, and neurologic examinations, routine laboratory evaluations, thoracic radiographs, abdominal ultrasound, electroretinography, and brain MRI were performed in all animals. Cerebrospinal fluid analysis and postmortem histopathologic results were recorded when available. Results Four dogs and three cats met the inclusion criteria. Lesions affecting the visual pathways were observed on magnetic resonance (MR) images in six cases. Location, extension, and MRI features were described. Neuroanatomic localization included: olfactory region with involvement of the optic chiasm (n = 4), pituitary fossa with involvement of the optic chiasm and optic tracts (n = 1), and optic nerves (n = 1). Of all lesions detected, five were consistent with intracranial tumors (two meningiomas, one pituitary tumor, two nasal tumors with intracranial extension), and one with bilateral optic neuritis that was confirmed by cerebrospinal fluid analysis. Histologic diagnosis was obtained in four cases and included one meningioma, one pituitary carcinoma, one nasal osteosarcoma, and one nasal carcinoma. Conclusions Central nervous system (CNS) disease should be considered in dogs and cats with acute blindness, even when other neurologic deficits are absent. This study emphasizes the relevance of MRI as a diagnostic tool for detection and characterization of CNS lesions affecting the visual pathways.  相似文献   

7.
Objective— To compare the diagnostic yield of conventional radiographs and computed tomography (CT) images of the skulls of dogs and cats with maxillofacial trauma (MFT).
Study Design— Prospective study.
Animals— Dogs (n=9) and 15 cats with MFT.
Methods— CT-scans and skull radiographs (4 standard projections) for each animal were evaluated using a semi-quantitative scoring system for the ability to identify 26 predefined, clinically relevant anatomic features (Part 1), and 27 predetermined potential traumatic injuries (Part 2). For Part 1, mean scores for each anatomic feature were recorded for every view and imaging modality. For Part 2, studies were evaluated for the frequency of cases where each predetermined traumatic injury was identified.
Results— Part 1: On radiographs it was easy to identify 17 of 26 anatomic features whereas 6 features were very difficult or impossible to identify on any view. All structures were considered easy or very easy to identify on CT. Scores for CT were lower than radiographs for evaluating dental occlusion and the integrity of the mandibular body. Part 2: CT scans demonstrated 1.6 times more maxillofacial injuries for dogs and 2.0 times more for cats than conventional radiographs. The average number of MFT injuries per animal by radiographs and CT-scan was 4.8 and 7.6 in dogs, and 3.8 and 7.7 in cats, respectively.
Conclusion— CT is superior to conventional skull radiography for identification of anatomic structures and traumatic injuries in dogs and cats. Skull radiography is useful for visualizing the mandibular body and dental occlusion.
Clinical Relevance— CT allows for accurate assessment, diagnosis and treatment planning of MFT in dogs and cats.  相似文献   

8.
Computed tomography (CT) of the thorax was performed in 28 dogs and five cats and findings were compared with previous thoracic radiographs. The sample population included all animals that had thoracic radiographs and a CT study within 5 days of each other, where the complete imaging studies were available for review. Thoracic radiographs were considered indeterminate in 31 patients and CT examinations were done to acquire additional information. The presence of additional information from CT relating to presence of pathology, location of pathology, extent of pathology, and involvement of mediastinal structures was recorded. Whether there was a change in diagnosis based on the CT findings was also recorded. In only 4/33 animals (all dogs) did CT fail to provide any new information for the parameters evaluated when compared with survey thoracic radiographs. Additional information about the pathology that was present was gained by CT in 5/5 cats and 21/ 28 dogs. New information on compartmental location of pathology was seen in 4/5 cats and 19/28 dogs. New information on pathology extent was noted in 5/5 cats and 20/28 dogs. Additional information regarding involvement of mediastinal structures was obtained in 2/5 cats and 10/28 dogs. A change in diagnosis was made in 3/5 cats and 13/28 dogs. In conclusion, CT is a valuable tool for evaluating intrathoracic disease. CT provides additional cross-sectional anatomic information that can aid in anatomic localization and evaluation of the extent of the pathology in question.  相似文献   

9.
This study investigates the clinical and pathologic findings associated with 173 primary brain tumors in our hospital population of dogs that presented between the years 1986 and 2002. Of the 173 primary brain tumors, 78 (45%) were meningiomas, 29 (17%) were astrocytomas, 25 (14%) were oligodendrogliomas, 12 (7%) were choroid plexus tumors, and 7 (4%) were primary central nervous system lymphomas. Smaller numbers of glioblastomas (n = 5), primitive neuroectodermal tumors (n = 5), histiocytic sarcomas (n = 5), vascular hamartomas (n = 4), and unclassified gliomas (n = 3) were identified. One dog had both a meningioma and an astrocytoma. Most tumors were located within the telencephalon, and seizures were the most common clinical presenting complaint. Of 168 tumors for which a location in the brain was recorded at postmortem examination, 79 were found to involve more than 1 brain division. Other neoplasms unrelated to the primary brain tumor were identified on postmortem examination in 39 dogs (23%). Intrathoracic and intraabdominal neoplasms were present at necropsy in 13 and 24 cases, respectively. Based on the results of this study, thoracic radiographs and abdominal ultrasonography may be indicated to look for extracranial neoplasia prior to advanced imaging of the brain or intracranial surgery.  相似文献   

10.
Primary and secondary bone tumours in the cat   总被引：2，自引：0，他引：2  
Both primary and secondary bone tumours are rare in cats. Of the twenty-four cases of primary bone tumour, benign or malignant, in the cats of our study, the most common tumour was osteosarcoma (fifteen cats). The osteosarcomas tended to occur in aged female domestic short-hair cats; nine of the fifteen originated in the long bones of the extremities and three involved the skull. Four juxtacortical osteosarcomas, three chondro-sarcomas, and one example each of oesteoma and osteoid osteoma were found. The four juxtacortical osteosarcomas developed in relation to cranial bones, a location not recorded previously in cats.
Of the five tumour-like lesions of bone simulating primary tumours, three were aneurysmal bone cysts and two were fibrous dysplasias.
Of the twenty-nine cats with soft tissue tumours or tumour-like lesions involving bone, eleven had fibrosarcoma, eight had squamous cell carcinoma, three had lymphosarcoma, two had rhabdomyosarcoma, and one example of each was malignant melanoma, haemangiosarcoma, reticulum-cell sarcoma, meningioma and myositis ossificans.
Osteoid osteoma, fibrous dysplasia and myositis ossificans were not previously recorded in the cat.  相似文献   

11.
Background: The benefits of endoscopic assistance to remove intracranial tumors in small animals are not described.
Objective: To evaluate the effectiveness of endoscopic-assisted intracranial tumor removal in dogs and cats.
Animals: Thirty-three dogs and 6 cats with intracranial tumors.
Methods: Retrospective study. CBC, serum chemistry profile, coagulation testing, blood typing, and systemic tumor staging, which included 3-view thoracic radiographs and abdominal ultrasound examination, were performed to detect other significant underlying disease in preparation of the animal for surgery. Magnetic resonance imaging was used in 37/39 cases to image the brain tumor. Surgical approach was dictated by the location of the tumor. Histopathologic examination of the tumor tissue was performed in all cases. Animals were followed throughout their postoperative course for complications and survival times. Statistical analysis (Kaplan-Meier curves) was performed to obtain median survival times in dogs with meningiomas.
Results: Use of an endoscope resulted in visualization of residual tumor and potentially more complete removal of the brain tumors. There were no clinically important complications associated with the use of the endoscope. Median survival time was 2,104 days for dogs with forebrain meningiomas surgically removed with endoscopic assistance and 702 days for dogs with caudal brain meningiomas.
Conclusions and Clinical Importance: These results demonstrate that the use of an endoscope to assist in brain tumor removal is apparently safe and might result in improved survival times.  相似文献   

12.
Meningioma is the most common primary brain tumor in cats, although there are few reports about their pathological features. To investigate the histopathological subtypes and immunohistochemical features including expression of cytokeratin and cell adhesion molecules, 45 cases of feline meningioma were examined. The mean age was 12.5 years (range 6–21 years). No statistically significant sex predilection was observed. Regarding the anatomical location of meningioma, tumors mostly developed in the cerebrum, followed by spinal cord and cerebellum, and multiple meningioma was observed in one cat. Microscopically, linear or focal mineralization was observed in 40 cases and cholesterol cleft was observed in 14 cases. Based on histopathological subtypes, there were 15 fibrous, 22 transitional, 2 meningothelial, 5 atypical, and 1 anaplastic meningiomas. These subtypes are classified into grade 1 (39 cases), grade 2 (5 cases), and grade 3 (1 case). There was no significant difference in the Ki-67 index among histological subtypes or grades. Immunohistochemically, the tumor cells were positive for cytokeratin in 5 cases (12.8%), vimentin in 17 cases (43.6%), E-cadherin in 36 cases (92.3%), β-catenin in 21 cases (53.8%), and N-cadherin in 1 case (2.6%), demonstrating the utility of E-cadherin-immunohistochemistry for the diagnosis of feline meningiomas.  相似文献   

13.
There are no evidence-based guidelines as to whether computed tomography (CT) or endoscopy should be selected as the first-line procedure when a nasal tumor is suspected in a dog or a cat and only one examination can be performed. Computed tomography and rhinoscopic features of 17 dogs and 5 cats with a histopathologically or cytologically confirmed nasal tumor were retrospectively reviewed. The level of suspicion for nasal neoplasia after CT and/or rhinoscopy was compared to the definitive diagnosis. Twelve animals underwent CT, 14 underwent rhinoscopy, and 4 both examinations. Of the 12 CT examinations performed, 11 (92%) resulted in the conclusion that a nasal tumor was the most likely diagnosis compared with 9/14 (64%) for rhinoscopies. Computed tomography appeared to be more reliable than rhinoscopy for detecting nasal tumors and should therefore be considered as the first-line procedure.  相似文献   

14.
Muscular metastatic neoplasia has been reported to be rare in domestic animals, however previous studies were based primarily on necropsy findings. The purpose of this retrospective study was to describe whole body computed tomography (CT) characteristics of confirmed muscular metastases in a cohort of dogs and cats presented for oncology evaluation. Medical records of 1201 oncology patients were reviewed. Included animals underwent pre and postcontrast whole body CT, and CT‐guided tru‐cut biopsy or fine needle aspiration of one or more metastatic lesions. Twenty‐one dogs and six cats met inclusion criteria, representing 2.08% of all canine oncology patients and 3.1% of all feline oncology patients. Mean age was 9.6 years. Postcontrast CT characteristics included well‐demarcated, oval‐to‐round lesions with varying enhancement patterns: ring enhancing (n = 16), heterogeneously enhancing (n = 8), or homogeneously enhancing (n = 5). Five animals showed concurrent and varying nodular patterns. In seven cases (five dogs and two cats), one single muscular nodule was observed. In 20 cases, two or more lesions were observed. In two cases, cardiac hypodense nodules were observed in the postcontrast CT, while appearing isodense in the precontrast study. Necropsy confirmed neoplasia in both of them. Locations of muscular metastases included epaxial/paraspinal muscles of the cervical, thoracic, and lumbar spine (n = 18), superficial muscles of the thoracic wall (n = 13), scapular/shoulder region (n = 3), hind limb (n = 3), and abdominal wall muscles (n = 1). Findings supported the use of pre and postcontrast whole body CT for oncologic staging in dogs and cats, especially for primary tumors characterized by a high metastatic rate.  相似文献   

15.
Evaluation of craniotomy in dogs and cats   总被引：4，自引：0，他引：4  
Over a reporting period of 5 years, craniotomy was performed in 26 dogs and 5 cats with various intracranial lesions. X-ray computed tomography was performed in all animals prior to surgery. Twenty dogs and all cats had intracranial neoplasms; of these, 14 were meningioma, and 11 represented a wide variety of brain tumors and skeletal tumors. Three dogs were treated surgically for traumatic, open-skull fractures with cerebral damage, and 3 underwent biopsy to evaluate chronic inflammatory brain disease. The overall medium survival time was 212 days, the 1-year survival rate was 39%, and the 2-year survival rate was 20%. Dogs and cats with meningioma survived a mean 198 and 485 days, respectively, with 1-year survival rates of 30% for dogs and 50% for cats. The overall median survival time for animals with tumors other than meningeal intracranial neoplasms was 414 days, with a 1-year survival rate of 40%. The death of 19% of all animals could be related to the combination of advanced brain disease and surgery. Because fatality seldom occurred as a direct result of surgery, morbidity and mortality associated with craniotomy in pet animals can be seen as acceptably low. In 29 of 34 craniotomies, dura mater defects were left unsutured and no adverse effects were seen.  相似文献   

16.
Precise and accurate patient positioning is necessary when doing stereotactic radiosurgery (SRS) to ensure adequate dosing to the tumor and sparing of normal tissues. This prospective cross‐sectional study aimed to assess feasibility of a commercially available modified frameless SRS positioning system for use in veterinary radiotherapy patients with brain tumors. Fifty‐one dogs and 12 cats were enrolled. Baseline and verification CT images were acquired. The verification CT images from 32 dogs and five cats had sufficient images for fusion to baseline CT images. A rigid box‐based fusion was performed to determine interfraction motion. Forty‐eight dogs and 11 cats were assessed for intrafraction motion by cine CT. Seventy percent of dogs and 60% of cats had interfraction 3D vector translational shifts >1 mm, with mean values of 1.9 mm in dogs, and 1.8 mm in cats. In dogs muscle wasting was weakly correlated with translational shifts. The maximum angular interfraction motion observed was 6.3° (roll), 3.5° (pitch), and 3.3° (yaw). There was no correlation between angular interfraction motion and weight, brachycephaly, or muscle wasting. Fifty‐seven percent of dogs and 50% of cats had respiration‐related intrafraction motion. Of these, 4.5% of dogs and 10% of cats had intrafraction motion >1 mm. This study demonstrates the modified Brainlab system is feasible for SRS in dogs and cats. The smaller cranial size and difference in anatomy increases setup uncertainty in some animals beyond limits usually accepted in SRS. Image‐guided positioning is recommended to achieve clinically acceptable setup accuracy (<1 mm) for SRS.  相似文献   

17.
The diagnosis and treatment of nasal foreign bodies usually includes a combination of rhinoscopy and imaging techniques, such as CT. The purpose of this retrospective, multicenter study was to describe the CT characteristics of nasal foreign bodies in dogs and cats and to determine if different nasal CT features exist between acute and chronic cases. Twenty dogs and six cats met the inclusion criteria. Eleven nasal foreign bodies (42%) were detected confidently with CT. The foreign body had a linear shape in 81% of cases and displayed a “tubular‐like appearance” in 54% of cases. In five cases (19%), a foreign body was suspected but not clearly visible. Additional CT changes were present in the nasal passages in 96% of the cases. The presence of turbinate destruction (P = .021) and mucosal thickening (P = .014) on CT were associated with the presence of a chronic nasal foreign body. In this sample, the nature of the foreign body did not influence its visibility and was not associated with specific CT characteristics. Computed tomography may be useful in the investigation of nasal foreign bodies, however, a negative CT examination does not exclude their presence.  相似文献   

18.
Published information regarding canine vertebral column mast cell tumors (MCTs) is limited. The objectives of this study were to report clinical and advanced imaging findings for a group of dogs with confirmed spinal MCT. Inclusion criteria for this retrospective case series were dogs with spinal magnetic resonance imaging (MRI) or computed tomography (CT) scans and a histological diagnosis of spinal MCT. Clinical, imaging, treatment, and outcome data were recorded. Four dogs met inclusion criteria. One dog had primary spinal MCT and three dogs had metastatic spinal MCT. All four dogs presented for paraspinal hyperesthesia and subacute progressive or acute myelopathy. All CT and MRI lesions were extradural. Two cases exhibited distinct masses in the epidural space. In one case, an epidural tumor invaded from the paravertebral musculature. One case exhibited polyostotic lesions indistinguishable from multiple myeloma by MRI. One dog with a primary epidural low‐grade MCT remains clinically normal 4 years postoperatively, following adjunctive lomustine. An epidural high‐grade MCT, metastatic from a cutaneous tumor, recurred within 2 months of surgery despite adjunctive vinblastine. Two high‐grade cases with concurrent visceral involvement were euthanized immediately after imaging. In dogs, MCT should be considered as a differential diagnosis for a progressive painful myelopathy and CT or MRI evidence of an extradural spinal lesion (epidural, paravertebral, or polyostotic). While more often associated with cutaneous or disseminated disease, MCT may also occur as a primary tumor of the epidural space in dogs.  相似文献   

19.
For canine and feline patients with head tumors, simultaneous irradiation of the primary tumor and mandibular and retropharyngeal lymph nodes (LNs) is often indicated. The purpose of this study was to assess the repeatability of a planning target volume (PTV) expansion protocol for these LNs. Two CT image sets from 44 dogs and 37 cats that underwent radiation therapy for head tumors were compared to determine LN repositioning accuracy and precision; planning‐CT (for radiation therapy planning) and cone‐beam CT (at the time of actual treatment sessions). Eleven percent of dogs and 65% of cats received treatment to their LNs. In dogs, the mandibular LNs were positioned more caudally (P = 0.0002) and the right mandibular and right retropharyngeal LNs were positioned more to the left side of the patient (P = 0.00015 and P = 0.003, respectively). In cats, left mandibular LN was positioned higher (toward roof) than the planning‐CT (P = 0.028). In conclusion, when the patient immobilization devices and bony anatomy matching are used to align the primary head target and these LNs are treated simultaneously, an asymmetrical PTV expansion that ranges 4–9 mm (dogs) and 2–4 mm (cats), depending on the directions of couch movement, should be used to include the LNs within the PTV at least 95% of the time.  相似文献   

20.
Feline acromegaly is predominantly caused by an adenoma of the pituitary gland, resulting in excessive growth hormone and insulin-like growth factor (IGF-1) secretion. In advanced cases, cats will display prominent facial features and upper airway congestion secondary to bony and soft tissue proliferation. The purpose of this study was to describe CT and MRI characteristics of soft tissues and skull bones in six cats with presumed acromegaly and to compare findings with those observed in 12 unaffected cats. In the five acromegalic cats with CT or MRI evidence of a pituitary tumor, frontal bone thickness was greater than age-matched controls with and without a history of upper airway disease. These five cats also had evidence of soft tissue accumulation in the nasal cavity, sinuses, and pharynx. One cat with insulin-resistant diabetes mellitus, elevated IGF-1, and a normal pituitary size did not have evidence of frontal bone thickening or upper airway congestion.  相似文献   

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