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Kayser-Fleischer Rings
Kayser-Fleischer rings are deposits of copper, seen as a brownish dis- coloration, in Descemet’s membrane. Although often visible to the naked eye (difficult in people with a brown iris), they are best seen with slit-lamp examination. Since they are a highly reliable sign of intra- cerebral copper deposition in Wilson’s disease (hepatolenticular degen- eration), any patient suspected of this diagnosis (i.e., with parkinsonism or dystonia presenting before age 50 years) should have a slit-lamp examination (as well as blood copper and ceruloplasmin, and urinary copper, measurements). Very occasionally cases of neuro- logical Wilson’s disease without Kayser-Fleischer rings have been reported.
References
Finelli PF. Kayser-Fleischer ring: Hepatolenticular degeneration (Wilson’s disease). Neurology 1995; 45: 1261-1262
Cross References Dystonia; Parkinsonism Kernig’s Sign
Kernig’s sign is pain in the lower back (and also sometimes the neck) and resistance to movement with passive extension of the knee on the flexed thigh in a recumbent patient. It is indicative of meningeal mechanosensitivity due to inflammation, either infective (meningitis) or chemical (subarachnoid hemorrhage), in which case it may coexist with nuchal rigidity and Brudzinski’s (neck) sign. If unilateral it may indicate irritation of the lumbosacral nerve roots from a ruptured intervertebral disc (in which case Lasègue’s sign may also be present).
References
Pearce JMS. Kernig and Brudzinski. In: Pearce JMS. Fragments of neurological history. London: Imperial College Press, 2003: 365-366 Cross References
Brudzinski’s (neck) sign; Lasègue’s sign; Nuchal rigidity Kernohan’s Notch Syndrome
Raised intracranial pressure as a result of an expanding supratentorial lesion (e.g., tumor, subdural hematoma) may cause herniation of brain tissue through the tentorium into the subtentorial space, putting pres- sure on the midbrain. If the midbrain is shifted against the contralateral margin (free edge) of the tentorium, the cerebral peduncle on that side may be compressed, resulting in a hemiparesis which is ipsilateral to the supratentorial lesion (and hence may be considered “false-localizing”).
There may also be an oculomotor nerve palsy ipsilateral to the lesion, which may be partial (unilateral pupil dilatation).
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References
Cohen AR, Wilson J. Magnetic resonance imaging of Kernohan’s notch. Neurosurgery 1990; 27: 205-207
Kernohan JW, Woltman HW. Incisura of the crus due to contralateral brain tumor. Arch Neurol Psychiatry 1929; 21: 274-287
Kole MK, Hysell SE. MRI correlate of Kernohan’s notch. Neurology 2000; 55: 1751
Cross References
“False-localizing signs”; Hemiparesis; Hutchinson’s pupil Kinesis Paradoxica
Kinesis paradoxica is the brief but remarkably rapid and effective movement sometimes observed in patients with Parkinson’s disease or post-encephalitic parkinsonism, despite the poverty and slowness of spontaneous movement (akinesia, hypokinesia; bradykinesia) seen in these conditions. It often occurs in response to alarm, excitement or emotion (e.g., in response to a genuinely funny joke).
Cross References
Akinesia; Bradykinesia; Hypokinesia; Parkinsonism Klazomania
Klazomania was the term applied to the motor and vocal tics seen as a sequel to encephalitis lethargica (von Economo’s disease), along with parkinsonism and oculogyric crises. This observation helped to pro- mote the idea that tics were due to neurological disease rather than being psychogenic, for example in Gilles de la Tourette syndrome.
References
Wohlfart G, Ingvar DH, Hellberg AM. Compulsory shouting (Benedek’s “klazomania”) associated with oculogyric spasm in chronic epidemic encephalitis. Acta Psychiatrica Scandinavica 1961;
36: 369-377 Cross References
Coprolalia; Echolalia; Parakinesia, Parakinesis; Tic Kleptomania
Kleptomania, a morbid impulse to steal, has been related to the obses- sive-compulsive spectrum of behaviors in patients with frontal lobe dysfunction.
References
Kozian R, Otto FG. Treatment of a patient with kleptomania and frontal lobe dysfunction. Journal of Neurology, Neurosurgery and Psychiatry2001; 70: 279 (abstract)
Cross References Frontal lobe syndromes Klüver-Bucy Syndrome
The Klüver-Bucy syndrome consists of a variety of neurobehavioral changes, originally observed following bilateral temporal lobectomy (especially anterior tip) in monkeys, but subsequently described K.qxd 9/28/05 10:31 PM Page 179
in man. The characteristic features, some or all of which may be present, are:
Visual agnosia (e.g., misrecognition of others) Hyperorality
Hyperphagia, binge eating Hypermetamorphosis Hypersexuality
Emotional changes: apathy; loss of fear, rage reactions Clinical causes of the Klüver-Bucy syndrome include:
Sequel of bilateral temporal lobectomy
Post-ictal phenomenon in a patient with a previous unilateral temporal lobectomy
Sequel to minor head trauma; subdural hematoma Tumor
Meningoencephalitis Pick’s disease
Alzheimer’s disease: especially hyperorality and hyperphagia, but it is rare to have all features
References
Anson JA, Kuhlman DT. Post-ictal Klüver-Bucy syndrome after tem- poral lobectomy. Journal of Neurology, Neurosurgery and Psychiatry 1993; 56: 311-313
Klüver H, Bucy P. Preliminary analysis of functions of the temporal lobes in monkeys. Archives of Neurology and Psychiatry 1939; 42: 979-1000.
Cross References
Apathy; Hypermetamorphosis; Hyperorality; Hyperphagia; Hyper- sexuality; Visual agnosia
Knee Tremor
A characteristic tremor of the patellae, sometimes known as knee bob- bing, juddering, or quivering, may be seen in primary orthostatic tremor (POT; “shaky legs syndrome”). It is due to rapid rhythmic con- tractions of the leg muscles on standing, which dampen or subside on walking, leaning against a wall, or being lifted off the ground, with dis- appearance of the knee tremor; hence this is a task-specific tremor.
Auscultation with the diaphragm of a stethoscope over the lower limb muscles reveals a regular thumping sound, likened to the sound of a distant helicopter. EMG studies show pathognomonic synchronous activity in the leg muscles with a frequency of 14-18Hz, thought to be generated by a central oscillator (peripheral loading does not alter tremor frequency).
A number of drugs may be helpful in POT, including phenobarbi- tone, primidone, clonazepam, and levodopa, but not propranolol (cf. essential tremor).
References
Heilman KM. Orthostatic tremor. Archives of Neurology 1984; 41:
880-881
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Brown P. New clinical sign for orthostatic tremor. Lancet 1995; 346:
306-307 Cross References Tremor
Körber-Salus-Elschnig Syndrome - see NYSTAGMUS
Kyphoscoliosis
Kyphoscoliosis is twisting of the spinal column in both the anteropos- terior (kyphosis) and lateral (scoliosis) planes. Although such defor- mity is often primary or idiopathic, thus falling within the orthopedic field of expertise, it may also be a consequence of neurological disease which causes weakness of paraspinal muscles.
Recognized neurological associations of kyphoscoliosis and scol- iosis include:
Chiari I malformation, syringomyelia
Myelopathy (cause or effect? Skeletal disease, such as achon- droplasia, is more likely to be associated with myelopathy than idiopathic scoliosis)
Cerebral palsy Friedreich’s ataxia Neurofibromatosis
Hereditary motor and sensory neuropathies Spinal muscular atrophies
Myopathies, e.g., Duchenne muscular dystrophy
Stiff person syndrome may produce a characteristic hyperlordotic spine. Some degree of scoliosis occurs in virtually all patients suffering from paralytic poliomyelitis before the pubertal growth spurt.
Cross References Camptocormia; Stiffness
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