Biomedical subjects
Publications and source records attributed to M Vandevelde.
The concept that a degenerative neurologic disease in German Shepherd Dogs (designated "German Shepherd Dog myelopathy") represents a dying-back disease process was not substantiated by morphologic and morphometric data derived from central and peripheral nervous system evaluation in 23 dogs. The occurrence of this identifiable disease complex in German Shepherd Dogs suggested a role by genetic determinants.
The distribution of canine distemper virus in the central nervous system was examined in 11 dogs with demyelinating encephalitis by the direct fluorescent antibody technique on paraffin sections of brain and spinal cord. In the grey matter there was a good correlation between the presence and severity of lesions and presence and amount of viral antigen. Large concentrations of virus were found in neurons and their processes. In most demyelinating lesions only small amounts of viral antigen were found, mostly located in astrocytes. The potential importance of the role of the astrocyte in demyelination in canine distemper virus infection is stressed.
One of 8 highly inbred Dalmatian pups was born with generalized body tremors, which interfered with the pup's ability to suckle, walk, and maintain sternal recumbency. The pup's head, neck, and limbs oscillated rhythmically when it attempted to perform any motor function. The pup was euthanatized at 8 weeks of age, after it became apparent that the disorder was likely to be permanent. The histologic diagnosis was cerebrospinal hypomyelinogenesis.
Various forms of 2 techniques for maximal decompression of the thoracolumbar spinal cord in dogs were evaluated clinically and histologically. Based on the results of this study, the veterinary surgeon could consider the following spinal decompression procedures: (1) deep dorsal laminectomy over 1 vertebra; (2) bilateral hemilaminectomy on 1 vertebra, with removal of articular processes and dorsal spinal plating; and (3) bilateral hemilaminectomy on 2 vertebrae, with the articular processes left intact. Of these 3, the 1st and 3rd techniques would probably be considered for use more often than the 2nd. Deep dorsal laminectomy over 2 vertebrae should be considered with reservation. Bilateral hemilaminectomy on 2 vertebrae, with rigid dorsal spinal plating and without articular processes at the ends of the defect, should not be used. Before using one of the techniques, the surgeon should consider the indications, advantages, and disadvantages for that technique.
Two young zebra siblings from consecutive pregnancies suffered from neurological disease, characterized by ventral deviation of the neck and tetraparesis which progressed to tetraplegia within a few weeks. On histological examination widespread neuronal degeneration was observed in the ventral horns of the spinal cord and in the lower brain stem. Ultrastructurally the neuronal degeneration was characterized by accumulation of neurofibrillary material resembling neurofilaments. The findings are compared to other diseases with neurofibrillary accumulation in man and animals.
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Six dogs that had a sudden onset and rapid progression of neurological signs with enlargement of the cranial vault at 6--8 weeks old were believed to have congenital hydrocephalus. There were severe inflammatory and necrotizing lesions in periventricular sites in the brain. A bacterial infection may have been the cause of this process.
Two dogs each had a fibrous tumor of the central nervous system. One tumor involved the spinal cord and ventral nerve root, and the other involved the midbrain and posterior brain stem. Both tumors had spindle-shaped cells arranged in rhythmic patterns. There was perivascular tumor cell infiltration in the adjacent parenchyma. The tumor cells strongly resembled fibroblasts and seemed to produce collagen. Because both tumors were near nerve roots and because their histological appearances were characteristic of nerve sheath tumors they were classified as central neurofibromas.
A horse that suddenly became recumbent had a focal ischemic infarct of the spinal cord between C6 and C7. The infarct was attributed to multiple fibrocartilaginous emboli. Adherence of fibrocartilaginous debris to the outer surface of the dura was interpreted as evidence that intervertebral disc degeneration and displacement of the nucleus pulposus had occurred and that the emboli arose from the disc.
Samples of cerebrospinal fluid (CSF) of 93 dogs with neurologic diseases were examined by cytomorphologic technique, and the changes in the CSF were correlated with histopathologic examinations of the central nervous system (CNS). It was concluded that CSF examination is a significant aid in obtaining a neurologic diagnosis and that good correlation exists between the CSF changes and the pathologic changes in the CNS. The CSF examination allows making a diagnosis of encephalitis and differentiation between viral and other causes (although in mycotic infection the cell membrane preparation can be used to identify the cause directly), could allow making differentiation between congenital malformations and congenital degenerative disease, and helps in identifying physical spinal cord damage, differentiating it from muscular, neurogenic, or functional disorders clinically presented as spinal ataxia. The CSF cytologic examination can indicate the presence of hemorrhage in the CNS. There is not enough experience available in the diagnosis of brain tumors by means of CSF examination; however, in dogs with lymphosarcoma in the CNS, CSF cytologic changes can be diagnostic.
Lissencephaly, a congenital absence of cerebrocortical convolutions, was discovered in 2 Lhasa Apso dogs by clinical and pathologic evaluation. Neurologic abnormalities, which became evident within the 1st year of life, included behavioral, visual, and convulsive disorders. The neurologic abnormalities were mild or delayed in onset after birth, indicating the dog is less dependent on the cerebral cortex for sensorimotor function than is man.
Clinicopathological findings of three different neoplastic conditions involving the spinal cord and nerve roots in three dogs are described. One sarcomatous intra-medullary tumor closely associated with the vasculature was classified as a reticulum cell sarcoma of the spinal cord. The second case had massive and widespread neoplastic proliferation of reticulohistiocytic cells around the perineurinal vessels of many spinal nerve roots. The process was classified as a primary neoplastic reticulosis of the spinal roots. Multiple highly malignant tumors, infiltrating the spinal cord were found in one thoracic and several lumbosacral spinal nerve roots in the third case. These were considered to be anaplastic neurofibrosarcomas because of high collagen content, intact nerve fibers, whorl formation, and the tendency to palisade in some areas.
A young cat had signs of tetraparesis that progressed to tetraplegia within a few weeks. Clinically, there was lower motor neuron disease with areflexia and muscle atrophy in all limbs. Degeneration of the motor neurons in the spinal cord was seen on histological examination. Ultrastructurally, the degeneration of nerve cells was characterized by abnormal proliferation of neurofilaments. These findings were compared to other motor neuron diseases and neurofibrillary accumulations in man and animals.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.