Paresis secondary to an extradural hematoma in a Sumatran tiger (Panthera tigris sumatrae).

A 15-yr-old female Sumatran tiger (Panthera tigris sumatrae) was presented to the Boren Veterinary Medical Teaching Hospital at Oklahoma State University with a 3-wk history of progressive hind limb weakness. Neurologic evaluation was limited to review of videotape that demonstrated weakness and ataxia with conscious proprioceptive deficits of the tiger's pelvic limbs. Spinal radiography demonstrated disc space narrowing, and myelography demonstrated a large extradural compressive lesion at the level of L2-3. Computed tomography did not reveal bone involvement. Surgery was performed to decompress the spinal cord and obtain a definitive diagnosis. A right hemilaminectomy was performed after a dorsal approach to the lumbar spine. Histologic examination of the mass revealed a consolidated extradural spinal hematoma, presumed to be secondary to intervertebral disc herniation. Despite incomplete resection of the mass and plastic deformation of the spinal cord, the tiger returned to normal ambulation within 3 wk of surgical decompression.     

Treatment of thoracolumbar spinal cord compression associated with Histoplasma capsulatum infection in a cat

CASE DESCRIPTION: A 7-year-old domestic shorthair cat with a 2-month history of decreased appetite and weight loss was examined because of paraparesis of 1 week's duration that had progressed to paraplegia 3 days earlier. CLINICAL FINDINGS: Neurologic examination revealed normo- to hyperreflexia and absence of deep pain sensation in the hind limbs and thoracolumbar spinal hyperesthesia. Neuro-anatomically, the lesion was located within the T3 through L3 spinal cord segments. Biochemical analysis and cytologic examination of CSF revealed no abnormalities. Radiography revealed narrowing of the T11-12 intervertebral disk space and intervertebral foramen suggestive of intervertebral disk disease. Myelography revealed an extradural mass centered at the T12-13 intervertebral disk space with extension over the dorsal surfaces of T11-13 and L1 vertebral bodies. TREATMENT AND OUTCOME: A right-sided hemilaminectomy was performed over the T11-12, T12-13, and T13-L1 intervertebral disk spaces, and a space-occupying mass was revealed. Aerobic bacterial culture of samples of the mass yielded growth of a yeast organism after a 10-day incubation period; histologically, Histoplasma capsulatum was identified. Treatment with itraconazole was initiated. Nineteen days after surgery, superficial pain sensation and voluntary motor function were evident in both hind limbs. After approximately 3.5 months, the cat was ambulatory with sling assistance and had regained some ability to urinate voluntarily. CLINICAL RELEVANCE: In cats with myelopathies that have no overt evidence of fungal dissemination, differential diagnoses should include CNS histoplasmosis. Although prognosis associated with fungal infections of the CNS is generally guarded, treatment is warranted and may have a positive outcome.     

Spinal meningeal sarcoma in a rottweiler puppy

An 11-week-old rottweiler puppy was presented for evaluation of progressive paraparesis, urinary and faecal incontinence. Radiography and myelography revealed widening of the vertebral canal and remodelling of several lumbar vertebrae associated with an intramedullary spinal mass. Magnetic resonance imaging revealed an extensive, heterogeneous mass involving the lumbosacral spinal cord. Histopathological examination indicated a meningeal sarcoma with very varied cytological architecture.     

Progressive ataxia due to central demyelination in Rottweiler dogs

A clinicopathological study of a neurologic disease in Rottweiler dogs was conducted. Clinical data were available on 16 dogs, 11 of which were examined pathologically. All dogs had a history of progressive gait abnormalities, which had commenced insidiously at an age varying from 1.5 to 3.5 years. In most dogs the fore limbs were affected prior to the hind limbs. At neurologic examination ataxia of all 4 limbs was seen, in some instances accompanied by an apparent paresis. Proprioceptive positioning was delayed whereas spinal reflexes were often hyperactive. Plain and contrast radiographs of the spine did not reveal any compressive lesions in 5 dogs examined. Cerebrospinal fluid analysis in 4 dogs was normal. Electrodiagnostic testing in 3 dogs revealed no abnormalities. At pathologic examination demyelinating lesions were found in the central nervous system. These were largely confined to the cervical spinal cord and brain stem and had a rather characteristic more or less symmetric distribution. Pedigree data suggested that the disease is transmitted genetically.     

HUMPY BACK OF SHEEP. CLINICAL AND PATHOLOGICAL OBSERVATIONS

Humpy back, a disease of Merino sheep in western Queesland, occurs during mustering for shearing. It is usually seen in summer 6-10 weeks after substantial rainfall and is thought to be caused by the ingestion of a toxic plant. The disease is characterised clinically by a short-stepping, stilted gait of the hind limbs, followed by lowering of the head, arching of the back and inability to continue walking. Histopathological examination of 8 cases from 5 properties revealed a Wallerian degeneration of the white matter throughout the length of the spinal cord with the ventral and lateral columns most severely affected. A similar degenerative change was seen in the posterior cerebellar peduncles of 3 of the sheep. A more severe hind limb incoordination with more extensive degeneration of the white matter of the spinal cord, medulla and cerebellum was seen in a case of humpy back of two years duration. Similar, but much milder, spinal cord lesions were found in apparently unaffected sheep from the same group as the sheep affected with humpy back on 2 properties. Severe myodegeneration of hind limb muscle groups was seen in 3 affected sheep. It was thought to be associated with the long rail journey (1500 km) to the laboratory after the sheep were affected in the field.     

马来熊后肢瘫痪成功治疗一例

1只雄性马来熊突发后躯瘫痪,初始表现为精神委顿、行动迟缓,继而发展为双后肢肌肉麻痹、瘫软,并伴随大小便失禁,因四肢无力支撑躯体,行动时后肢须拖拉前行。采集患熊的粪、尿镜检,结果未见异常,结合其发病突然的临床特征,诊断为因外力损伤造成的下运动神经元瘫痪。下运动神经元瘫痪,是脊髓周围神经或脑周围神经的运动纤维受损的结果。针对病情采取了中西医结合的治疗方法,一方面利用冲击疗法肌肉注射泼尼松龙,以抑制神经炎症的蔓延,并增强神经元的兴奋性和突触的传递;另一方面采用穴位注射疗法,将地塞米松、盐酸普鲁卡因、VB1和VB（12）注射液混合均匀后于患熊的＂百会穴＂注入,直接作用于受损神经周围,使其在刺激下加速修复;同时口服大活络丸,舒筋活络、消肿止痛。经过4周左右的积极治疗,该马来熊后肢逐渐恢复,直至站立自如,精神活泼,完全康复。     

IMAGING DIAGNOSIS—SPINAL EPIDURAL HEMANGIOSARCOMA IN A DOG

An 8‐year‐old, male Boxer was examined for an acute onset of ambulatory paraparesis. Neurologic examination was consistent with a T3‐L3 myelopathy. Myelography revealed an extradural spinal cord compression in the region of the T10‐T13 vertebrae. On magnetic resonance (MR) imaging, a well‐defined epidural mass lesion was detected. The mass was mildly hyperintense on T1‐weighted, hyperintense on T2‐weighted and STIR images compared to normal spinal cord and enhanced strongly and homogenously. Postmortem examination confirmed a primary epidural hemangiosarcoma. Findings indicated that the MRI characteristics of spinal epidural hemangiosarcoma may mimic other lesions including meningioma and epidural hemorrhages/hematomas of non‐neoplastic etiology.     

Thoracic vertebral chordoma in a domestic ferret (Mustela putorius furo).

A castrated adult male 1.0-kg domestic ferret (Mustela putorius furo) was referred for evaluation of a mass of >5 mo duration that was associated with the thoracic spine. The ferret had motor dysfunction and no conscious proprioception or pain perception in either hind limb. Segmental reflexes were present. Survey radiography, myelography, and magnetic resonance imaging showed a mass involving the ninth and 10 thoracic vertebrae and compressing the spinal cord. Decompressive surgery was performed, but clinical signs persisted. A diagnosis of chordoma was made using histopathology and immunohistochemistry. This is the first reported case of a chordoma involving the thoracic vertebrae in a domestic ferret.     

Paresis in an Asian small clawed otter (Aonyx cinereus) associated with vertebral and ischial osteolysis caused by a malignant lymphangiosarcoma

A 10-yr-old male intact Asian small clawed otter (Aonyx cinerus) was presumptively diagnosed by histopathology and immunohistochemistry with lymphangiosarcoma after bony destruction of the ischium and spinal column from local tumor invasion had caused progressive signs of hind limb lameness and paresis/paralysis, which led to humane euthanasia. At necropsy, the primary tumor was identified as a flocculent mass present under the caudal lumbar vertebrae. Multiple nerves were seen to run from the spinal cord into the wall of the mass. This mass had locally invaded the surrounding muscle, vertebral column, and spinal cord, which led to the clinical signs noted at presentation. Bony destruction was severe with almost complete obliteration of the right ischium and osteolysis of L6, exposing the spinal cord beneath. The tumor had metastasized to at least two different sites within the spleen. The abdominal tumor was confirmed to be of endothelial origin by the use of immunohistochemical staining for factor VIII-related antigen and was confirmed as lymphatic origin versus vascular origin because of the lack of red blood cells within the vessels. The length of time from initial presentation with hind limb lameness to euthanasia because of hind limb paralysis was 4 mo. This is the first report of lymphangiosarcoma, an uncommon malignant neoplasm of lymphatic origin, in a mustelid and the first report of neoplastic disease in an Asian small clawed otter. In addition, the presentation of hind limb paresis associated with bony lysis because of local tumor invasion has not been previously reported with lymphangiosarcoma in humans, domestic animals, or nondomestic animals.     

Total vertebrectomy for stabilisation of chronic spinal lumbar luxation in a paraplegic dog without nociception

An adult male crossbred dog was referred with a history of a road traffic accident that took place 1 month earlier. Neurological examination revealed paraplegia with absent nociception in the pelvic limbs. On epaxial palpation, significant curvature of the anatomical axis of the spine between the third and fourth lumbar vertebrae was observed, with the presence of a bone end almost piercing the dog's skin. Survey radiographs of the lumbar spine revealed severe dislocation between L3 and L4 vertebrae. During surgery, the spinal cord was not visible between the dislocated segments. Because of difficulties in reducing the lumbar luxation during surgery, vertebrectomy and vertebral shortening were performed. After alignment between vertebrae L3 and L5, eight cortical orthopaedic screws and bone cement were used for fixation. After 30 days, the dog started to use a wheelchair and was considered by its owner to have a good quality of life with no evidence of pain. To the authors’ knowledge, this is the first case of severe luxation treated by total vertebrectomy and spine shortening in a dog. This surgery can be considered as an option in the management of severe spine luxation when the spinal cord is physically transected.     

Congenital kyphosis secondary to lumbar vertebral hypoplasia causing paraparesis in a Friesian foal

A 5‐day‐old Friesian colt was presented with a history of severe bilateral pelvic limb weakness since birth. Clinical examination revealed a painful dorsal deviation of the spinous processes of the lumbar vertebrae, pelvic limb paraparesis and grade 4/5 ataxia. Radiographic examination revealed kyphosis due to hypoplasia and malformation of the 5 lumbar vertebrae present. At myelography performed immediately after euthanasia, dorsal deviation of the myelographic contrast column was demonstrated at the level of T18–L4 with suspected spinal cord compression noticeable at L1. There was no lateral deviation of the spinal cord or scoliosis of the vertebrae visible.     

Congenital syringohydromyelia in a crossbred (Holstein-Friesian × Japanese Black) beef calf

A 5-day-old male crossbred beef calf presented with a well-coordinated bilateral hopping gait of the hind limbs. Postmortem CT showed a poorly defined oval-shaped region at the L3–L4 spinal segments, which had high signal intensity on T2 weighted postmortem MRI images. On pathological examination, we identified a large cystic cavity filled with a large amount of cerebrospinal fluid on the cut surface of the spinal region. Histopathological examination revealed that the spinal cord parenchyma was compressed by the cystic structure, and the cystic cavity was lined with a thin layer of discrete ependymal cells, indicating syringohydromyelia. This is the first reported case of a Holstein-Friesian × Japanese Black crossbred calf with solitary syringohydromyelia. Our findings suggest that myelodysplasia with cystic cavities can be suspected by CT, without the need for MRI.     

Treatment of a prolapsed lumbar intervertebral disc in a ferret

A seven-month-old, male ferret had acute paraplegia and radiographs showed signs of disc prolapse between the second and third lumbar vertebrae (L2/3). Hemilaminectomy was performed to decompress the spinal cord. Histological examination revealed that the extradural material was consistent with annulus fibrosus and the L2/3 articular facets were enlarged as a result of bone remodelling. The ferret became ambulatory one month postoperatively. Five months postoperatively, the ferret had normal posture with mild proprioceptive deficits in the pelvic limbs, and fusion of the L2 and L3 vertebral bodies.     

Metastatic anal sac adenocarcinoma in a dog presenting for acute paralysis

A 4-year old, female spayed terrier was referred for hind end paresis that rapidly progressed to paralysis. Spinal radiographs revealed vertebral collapse and bony lysis. Myelography confirmed spinal cord compression and surgical exploration found an extradural soft tissue mass. Metastatic anal sac adenocarcinoma was diagnosed at postmortem examination.     

Surgical treatment of an intramedullary spinal cord hamartoma in a dog

A 9-year-old spayed female Golden Retriever was examined because of progressive hind limb lameness. Magnetic resonance imaging of the thoracic and lumbar portions of the vertebral column revealed a focal, contrast-enhancing, intramedullary spinal cord mass. The history, signalment, and magnetic resonance findings were suggestive of spinal cord neoplasia. A hemilaminectomy, durotomy, and longitudinal myelotomy were performed, and a 1 X 1-cm mass that contained numerous blood vessels was removed with blunt dissection. Results of histologic examination and immunohistochemical staining of the mass suggested that it was a hamartoma. The dog improved after surgery, with no evidence of a recurrence of clinical signs 14 months after surgery. Vascular malformations of the CNS in dogs include hamartomas, hemangiomas, angiomas, hemangioblastomas, meningocerebral hemangiomatosis, and arteriovenous malformations. A hamartoma is a non-neoplastic overgrowth of cells or an improper proportion of cells that are normally in the involved tissue. Although magnetic resonance imaging may be helpful in determining the extent of the lesion in dogs with vascular malforrmations, it cannot be used to distinguish neoplastic from non-neoplastic formations. Excision may result in a good outcome for dogs with an intramedullary spinal cord hamartoma.     

Ataxia due to lymphosarcoma in a young horse

A 20-month-old, Standard-bred colt was presented with an acute onset of hindlimb ataxia. Clinical and radiographic examination identified a compressive lesion affecting the spinal cord at the level of the 17th to 18th thoracic vertebrae. After euthanasia, post-mortem examination revealed a tumour in the epidural space, diagnosed histologically as a lymphosarcoma. Neoplastic lymphoid cells were also present in the abdominal lymph nodes and brain. Because of the disseminated nature of lymphosarcoma in the horse, involvement of the central nervous system is likely to be more common than is presently recognised.     

Extradural spinal liposarcoma in a dog.

An 8-year-old female Doberman Pinscher was examined because of progressive, asymmetric, ambulatory caudal paraparesis. Myelography revealed extradural left ventrolateral spinal cord compression over the first and second lumbar vertebral bodies. A left hemilaminectomy, extending from the thirteenth thoracic to the second lumbar vertebrae, was done, and an extradural mass was removed. The tumor was identified histologically as myxoid liposarcoma. The dog's neurologic function improved gradually after surgery; however, at 7 months after surgery, hind limb neurologic function deteriorated rapidly over a 5-week period, presumably because of local recurrence of the tumor. The dog was euthanatized; necropsy was not permitted.     

Neurological signs in a horse due to metastases of an intestinal adenocarcinoma

A 22-year-old Dutch Warmblood mare was referred to Utrecht University with progressive left hind limb paresis and hyporeflexia. The preliminary clinical diagnosis was the neurological form of equine herpes virus (EHV-1) infection. Within 1 day of admission, the mare became recumbent and deteriorated rapidly. Postmortem examination revealed an adenocarcinoma of the caecum, with metastases in all regional lymph nodes and extending from the lumbar nodes into the vertebral canal, causing spinal cord compression and destruction of the left 4th and 5th lumbar nerves.     

Vaccine-associated rhabdomyosarcoma with spinal epidural invasion and pulmonary metastasis in a cat

A 7-year-old, female, domestic medium-haired cat had a recurrent deep dermal mass in the interscapular region after initial surgical removal 3 months earlier. The cat had received a killed rabies vaccine and a five-in-one vaccine in the same area about 2 months prior to the first surgery. The relapsed mass was diagnosed as vaccine-associated sarcoma. The cat was euthanized 2 months later because of hind limb paralysis. At necropsy, multiple, poorly demarcated, nodular masses were seen in the muscles around the shoulders, neck, and thoracic vertebrae. Pulmonary metastasis and spinal epidural invasion at T1-T3 with regional cord compression and malacia were observed. Microscopically, the masses consisted of interwoven bundles of spindle cells with prominent multinucleated giant cell formation. The neoplastic cells stained strongly positive for myoglobin, and moderately but variably positive for vimentin, desmin, and alpha- smooth muscle actin. Phosphotungstic acid-hematoxylin staining revealed cytoplasmic striations in scattered tumor cells. The tumor was considered a vaccine-associated rhabdomyosarcoma.     

Acute intraparenchymal spinal cord injury in a cat due to high-rise syndrome

A 9-year-old spayed female Bengal Red cat was evaluated for high-rise syndrome. The cat had paraplegia of the hind limbs, intact reflexes and pain perception, and hyperesthesia in the caudal thoracic area. Mentation, cranial nerve function, forelimb proprioceptive responses, and spinal reflexes were normal. There were no abnormalities on radiographs or computed tomography scan, but magnetic resonance imaging revealed a hyperintense intraparenchymal spinal cord lesion on T2-weighted and T2 fat saturation images.