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31.
Syringomyelia is an important morbidity source in Cavalier King Charles Spaniels. Although abnormal cerebrospinal fluid (CSF) flow secondary to Chiari malformations is thought to cause syringomyelia in humans, this relationship is unknown in dogs. We used phase-contrast magnetic resonance (MR) imaging to evaluate CSF flow in dogs. Fifty-nine Cavalier King Charles Spaniels were assigned a neurologic grade reflecting their neurologic status. Five normal control dogs of other breeding were imaged for comparison. The presence of syringomyelia was noted from sagittal MR images. The pattern and velocity of CSF flow were assessed using phase-contrast cine MRI at the foramen magnum, C2–C3 disc space, and within syrinxes. Flow was measured most easily with the neck flexed to mimic standing. CSF flow velocity in the dorsal aspect of the subarachnoid space at the foramen magnum was significantly higher in control dogs than Cavalier King Charles Spaniels ( P =0.035). Flow was obstructed at the foramen magnum in 41 of 59 Cavalier King Charles Spaniels. Turbulent flow and jets were associated with syringomyelia presence and severity, and CSF flow velocity at C2/3 dorsally was inversely related to the presence of syringomyelia ( P =0.0197). Peak dorsal subarachnoid space CSF flow velocity at the foramen magnum and C2–C3 were together highly predictive of syringomyelia. CSF flow can be assessed in dogs using phase-contrast cine MRI. Obstruction to flow at the foramen magnum is common in Cavalier King Charles Spaniels and CSF flow pattern and velocity are related to the presence of syringomyelia.  相似文献   
32.
A Cavalier King Charles Spaniel was presented with acute onset, life-threatening dysphagia suspected to be secondary to medulla oblongata compression caused by caudal occipital malformation syndrome. The patient required urgent tracheostomy tube placement to remain stable and was subsequently cured of the presenting neurological deficits by foramen magnum decompressive surgery. Neurogenic dysphagia is a relatively common presenting sign in human Chiari malformation syndromes, but has not been described as a major clinical sign in veterinary patients. Caudal occipital malformation syndrome should be included in the differential diagnosis list for susceptible breeds presenting with dysphagia. Early recognition favours expeditious surgical intervention and a positive outcome in human patients, and this may also be the case in veterinary patients.  相似文献   
33.
OBJECTIVE: To report a technique for correction of atresia ani and rectovestibular fistula with fistula preservation, and outcome in 2 dogs. STUDY DESIGN: Case report. ANIMALS: Two intact female puppies. METHODS: The fistula was approached by episiotomy. A vertical median perineal incision was made starting dorsal to the anal region and extended to surround the fistula. The rectum and vagina were separated, and the end of the fistula was sutured to the skin. RESULTS: Early postoperative complications included constipation, fecal incontinence, and perineal soiling, but long-term outcome was good in both dogs. CONCLUSION: With careful dissection, the fistula and internal anal sphincter can be preserved and used in the surgical reconstruction of the anal canal and anus. CLINICAL RELEVANCE: Preservation of the fistula may provide an internal sphincter that contributes to a better functional result during correction of atresia ani. A surgical approach that combines episiotomy and perineal incision for separation of the vagina and rectum, and preserves the fistula may decrease the risk of dehiscence.  相似文献   
34.
A twenty-month-old Chihuahua male dog was presented to us suffering with ataxia. Based on the physical examination, X-ray and magnetic resonance imaging (MRI) examinations, we diagnosed the dog with hydrocephalus, Chiari I malformation and syringomyelia. Treatment consisted of internal medical treatment and the placement of a ventriculoperitoneal (VP) shunt. The ventricular dilatation was relieved and the dog improved neurologically; however, the Chiari I malformation and syringomyelia remained after surgically positioning the VP shunt.  相似文献   
35.
Disproportionate dwarfism is reported in two bovine siblings. Affected animals were similar in appearance and were characterized by shortening of the limbs. Pelvic limbs were noticeably shorter than the pectoral limbs. The axial skeleton was not noticeably affected, but the back sloped because of the shorter pelvic limbs. Sloping of the back was accompanied by thoracic kyphosis and lumbar lordosis.
Comparison of the length of bones from an affected animal with those from a normal animal indicated that major growth retardation occurred in the femur, tibia, and metatarsal bones. Histological examination of the physes indicated a reduction in cartilage cell maturation and matrix calcification. This was associated with a reduction of osteogenesis and the formation of thickened, shortened primary trabeculae surrounded by fibrous and poorly vascularized bone marrow.  相似文献   
36.
OBJECTIVE: To assess radiologically the caudal vertebrae of a male alpaca with an abnormal tail, and nine of his offspring. PROCEDURE: Right lateral and ventrodorsal radiographs were taken of the caudal vertebrae. RESULTS: The caudal vertebral abnormalities in these alpacas included vertebral subluxation, hemivertebrae, wedge hemivertebrae and block vertebrae. CONCLUSION: These malformations in offspring of one sire suggest a hereditary basis for congenital caudal vertebral malformations in the alpaca.  相似文献   
37.
杧果畸形病是国际上为害卡亡果生产的一种严重病害.无有效化学药剂可以控制,也未发现抗病品种。目前.此病在攀枝花市零星种植或失管的卡亡果园发病较为严重.成片的柁果基地也有零星发生.且呈蔓延扩展趋势。国内有关卡亡果畸形病病原鉴定方面的报道较多.但无田间防治研究的报道。本文采取重度回缩修剪、结合其他措施对卡亡果畸形病进行防控研究。结果表明,与修剪处理前相比。处理1第1年发病率降低64.4%.单株产量增加10.28kg:第2年发病率降低60.1%,单株产量增加36.31kg:第3年发病率降低79.2%,单株产量增加28.79kg。处理2第1年发病率降低71.6%.单株产量增加6.89kg:第2年发病率降低62.8%,单株产量增加29.94kg:第3年发病率降低84.5%.单株产量增加25.17kg。  相似文献   
38.
39.
Chiari‐like malformation (CM) and syringomyelia (SM) are common illnesses that can cause debilitating neuropathic pain in Cavalier King Charles spaniels (CKCS). The current imaging modality to screen CKCS for CM/SM is MRI of the brain and cervical spine. Magnetic resonance imaging provides good soft tissue detail and contrast of the cerebellum and cervical spinal cord. Computed tomography (CT) is another cross‐sectional imaging technique that facilitates brain and neck evaluation; however, soft tissue resolution does not match that of MRI. Computed tomography benefits include identification of concurrent craniocervical junction anomalies (atlantooccipital overlap) and shorter imaging/anesthesia times with the ability to use only sedation. The aim of this retrospective, method comparison study is to assess the utility of multidetector CT for screening CM and SM in CKCS as compared to high‐field MRI. Three groups of observers with different levels of experience graded CM and SM based on the British Veterinary Association/Kennel Club CM/SM classification criteria. Thirty CKCS underwent multidetector CT and 3 Tesla MRI studies. Computed tomography and MRI studies were reviewed at different timepoints to minimize bias. Computed tomography has lower Cohen's Kappa agreement for each observer group compared to MRI. The intraclass correlation coefficient averaging CM and SM for all groups was excellent using MRI, while CT was poor for SM and moderate for cerebellar herniation. Greater observer experience resulted in a higher agreement for CT and MRI. Magnetic resonance imaging should remain the standard for screening of CM and SM as CT can result in misclassification and greater disagreement.  相似文献   
40.
芒果畸形病是对芒果生产最具破坏性的病害之一。目前国际上虽对其进行了大量的研究,但对其病原、发病因子、侵染循环等仍未有定论,且尚未找到有效的防治方法。笔者结合国外相关研究资料,介绍了对芒果畸形病的研究概况,以期引起芒果生产者的重视,并供研究者参考。  相似文献   
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