Biomedical subjects

K E Knowles

Publications and source records attributed to K E Knowles.

4 recordsLinked to original sources

PubMed1996

Behavioral changes associated with suspected complex partial seizures in bull terriers.

OBJECTIVES: To identify and treat a range of abnormal behavior, including tail chasing, unprovoked aggression, and extreme irrational fear, in Bull Terriers and to correlate the behavioral signs with electroencephalogram (EEG) or anatomic evidence of abnormal brain geometry or deafness. DESIGN: Prospective clinical study. ANIMALS: 8 affected and 5 unaffected (control) Bull Terriers. PROCEDURE: All dogs were examined neurologically, including use of EEG, brainstem auditory-evoked response, and computed tomography or postmortem examination of the brain. In addition, plasma concentrations of zinc, copper, and iron, and the activity of zinc- and copper-dependent enzymes (alkaline phosphatase and ceruplasmin oxidase) were measured in affected and control dogs. RESULTS: An abnormal EEG was found in 7 of 7 affected dogs and in none of the control dogs subjected to this examination. Seven of 8 affected dogs and 2 of 3 controls had various degrees of hydrocephalus. Metal ion and enzyme concentrations were not different between affected and control dogs. Treatment with phenobarbital was effective in 5 of 7 dogs. CLINICAL IMPLICATIONS: Bull Terriers with compulsive tail chasing and extreme affective disorders should be regarded as neurologically disturbed, with partial seizures perhaps underlying their behavior. Treatment with anti-convulsants is a logical first step in treatment.

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PubMed1993

Prognosis after surgical excision of cerebral meningiomas in cats: 17 cases (1986-1992).

Long-term follow-up information was obtained for 17 cats with cerebral meningiomas treated by surgical excision. Three cats died or were euthanatized in the immediate postoperative period: 2 cats, because of brain herniation and 1 cat, because of acute renal failure. In the remaining 14 cats, most clinical signs resolved within 1 week of surgery. Three cats (21.4%) had confirmed or presumed local tumor recurrence. Two of these cats developed recurrent neurologic signs, and died or were euthanatized at 3 and 9 months, respectively, after surgery. One cat was euthanatized for an unrelated problem 72 months after surgery, and on postmortem examination, had a recurrent meningioma at the surgery site. The remaining 11 cats (78.6%) did not develop evidence of local tumor recurrence within follow-up periods ranging from 18 to 47 months (median, 27 months).

Animals↗

PubMed1988

Auditory-evoked responses of dogs with different hearing abilities.

Sixteen dogs were separated into three groups, based on clinical impressions of their abilities to hear and historical information pertaining to their hearing loss: group I (n = 7) had normal hearing, group II (n = 4) had reduced hearing and group III (n = 5) were deaf. Monaural clicks of alternating polarities were used to elicit brainstem auditory-evoked responses. The responses of the normal group and of the reduced hearing group consistently had four major peaks (I, II, III-IV, V) with latencies similar to those previously reported in dogs with normal hearing. No difference (p greater than or equal to 0.05) was found in mean latencies of the four major waveforms when comparing the normal group with the reduced hearing group. Significant reductions in mean amplitudes of waves I (p less than 0.01) and II (p less than 0.025) were found in the reduced hearing group. No recognizable waves could be recorded from the deaf group, indicating a lack of peripheral auditory function.

Animals↗

PubMedDate not supplied

Laryngeal paralysis-polyneuropathy complex in young Rottweilers.

Five Rottweiler puppies from 3 unrelated litters developed inspiratory stridor at 11-13 weeks of age. Physical examination disclosed tetraparesis in all dogs, and bilateral lenticular cataracts in 4 dogs. Laryngeal examination under light anesthesia showed laryngeal paralysis in all dogs. Electrodiagnostic testing revealed denervation potentials in the distal appendicular muscles of 4 dogs tested and in the intrinsic laryngeal muscles of 2 dogs tested. Motor nerve conduction velocity was slightly low in 1 dog. Neurogenic muscular atrophy was found in distal appendicular muscles (n = 3) and intrinsic laryngeal muscles (n = 2), and degenerative changes were found in peripheral nerves (n = 3) and recurrent laryngeal nerves (n = 2). No abnormalities were detected in the spinal cord, spinal nerve roots, or ganglia of 3 dogs autopsied. The clinical, electrophysiologic, and histopathologic findings support a diagnosis of polyneuropathy and resemble the finding reported in young Dalmatians. Young dogs with laryngeal paralysis should be evaluated neurologically to rule out a more generalized polyneuropathy. The condition is suspected to be hereditary in nature and the prognosis is poor.

Animals↗