Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027066 (myoclonus)
 4,275 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied a 24-year-old man who had reading epilepsy after removal of a left frontal arteriovenous malformation. Lesion analysis by means of a neuroanatomic template placed a 2-cm region of encephalomalacia anterior to the left central sulcus in premotor cortex (Brodmann's area 6). Lexical and nonlexical reading activation tests demonstrated seizures during reading and increased discharge rates when the patient was reading aloud or silently articulating. Seizures (perceived or actual jaw clicking) were electrographically characterized by brief left frontocentral epileptiform transients. Grapheme to phoneme transformation, not linguistic complexity, appears to be the critical stimulus in some reading epilepsies. The case adds anatomic relevance to the phonologic component of reading and supports the putative role of dominant premotor cortex in activation of precise sequences of motor linguistic output in reading and writing. Reading epilepsy may be a reflex or action myoclonus syndrome localized to Brodmann's area 6 (Exner's area).
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PMID:The role of dominant premotor cortex and grapheme to phoneme transformation in reading epilepsy. A neuroanatomic, neurophysiologic, and neuropsychological study. 152 84

Pseudoxanthoma elasticum is a rare hereditary disorder of elastic tissue with central nervous system manifestations due to occlusive vascular disease and aneurysm formation. Here we report the first recorded case of an intracranial arteriovenous malformation (AVM) in a patient with pseudoxanthoma elasticum. The AVM, which was located in the pons, also had an unusual manifestation, namely palatal myoclonus.
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PMID:An intracranial arteriovenous malformation and palatal myoclonus related to pseudoxanthoma elasticum. 276 15

We describe a patient with a longstanding paraplegia who developed spinal myoclonus on 3 different occasions spanning one year, once after an enhanced CT scan and twice after excretory urographies, one of which was also followed by a generalized tonic-clonic seizure. To our knowledge only one case of spinal myoclonus secondary to the administration of intravenous contrast material in a patient with a spinal arteriovenous malformation has yet been reported. Taken together, the findings in these cases suggest that spinal myoclonus following intravenous iodine administration is indicative of an underlying spinal cord lesion.
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PMID:[Spinal myoclonus secondary to the intravenous administration of iodine contrast media]. 747 10

An 81-year-old man was admitted with a 3-month history of progressive dementia. Neurological examination revealed marked dementia, parkinsonism and myoclonus in his extremities. His cerebrospinal fluid examination was normal. An electroencephalogram showed a mildly slowed background. Computed tomography (CT) disclosed diffuse low-density areas in bilateral cerebral white matter. Contrast-enhanced CT demonstrated vermiform enhancement of engorged cortical veins, suggesting increased pressure of the venous system. Magnetic resonance imaging (MRI) disclosed diffuse high-intensity areas in bilateral cerebral white manner on T2-weighted images, and abnormal flow-voids presenting venous congestion on proton-density images. Cerebral angiography revealed arteriovenous malformation (AVM) fed by four branches of the right external carotid artery with retrograde drainage into the right transverse sinus, superior sagittal sinus, and dilated cortical veins. The ipsilateral sigmoid sinus was not visualized. After transarterial embolization, transvenous embolization of the right transverse sinus was performed. These treatments resulted in a marked clinical improvement. We emphasize the role of AVM as a cause of progressive dementia.
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PMID:[A case of dural arteriovenous malformation associated with progressive dementia showing marked improvement with endovascular treatment]. 961 72

Myoclonus of the middle ear is a rare condition characterized by abnormal repetitive muscle contractions of the tympanic cavity. In this paper we describe what we believe is the first reported case of continuous high-frequency objective tinnitus caused by middle ear myoclonus. During exploratory tympanomastoidectomy it was hypothesized that a small dural arteriovenous malformation not identified on previous tests was the cause of the tinnitus. However, complete disappearance of the tinnitus during administration of curare for anesthesia led us to believe that the tinnitus might have been caused by myoclonus of the middle ear. Sectioning of the stapedius and tensor tympani tendons rendered the patient asymptomatic and confirmed the diagnosis of middle ear myoclonus. At follow-up of one year, the patient's quality of life had improved substantially; the tinnitus did not recur and she no longer had vertigo.
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PMID:Continuous, high-frequency objective tinnitus caused by middle ear myoclonus. 981 32

We report a 56-year-old woman with progressive gait disturbance. Her mother had Parkinson's disease with onset at age 70. She died at age 74 and the post-mortem examination confirmed the diagnosis of Lewy body positive Parkinson's disease. The patient was well until the age of 50(1995) when she noted an onset of resting tremor and difficulty of gait. She also developed delusional ideation and was admitted to a psychiatric service of another hospital, where a major tranquilizer was given. The delusion disappeared but she developed marked rigidity. The major tranquilizer was discontinued and an anticholinergic and amantadine HCl were given. She showed marked improvement to Hoehn and Yahr stage II and was discharged. In 1995, when she was 52 years of the age, she developed delusion again and a major tranquilizer was given. She developed marked parkinsonism again and became Hoehn and Yahr stage V. The major tranquilizer was discontinued and she was treated with levodopa/carbidopa, trihexyphenidyl, bromocriptine, and dops. She improved remarkably to stage II. She was admitted to our service on October 8, 1996 for drug adjustment. She was alert and not demented. She was anxious but delusion or hallucination was noted. Higher cerebral functions were intact. Cranial nerve functions were also intact except for masked face and small voice. Her posture was stooped and steps were small. She showed retropulsion and moderate bradykinesia. Resting tremor was noted in her left hand. Rigidity was noted in both legs. No cerebellar ataxia or weakness was noted. Deep tendon reflexes were within normal range and sensation was intact. Her cranial MRI revealed some atrophic changes in the putamen, in which a T 2-high signal linear lesion was seen along the lateral border of the putamen bilaterally. In addition, posterior part of the putamen showed T 2-low signal intensity change. She was treated with 1.6 mg of talipexole, 6 mg of trihexyphenidyl, and 100 mg of L-dops. She was in stage III of Hoehn and Yahr. She developed neurogenic bladder with a large amount of residual urine for which she required catheterization. She was transferred to another hospital. Despite drug adjustment, she lost response to levodopa and her parkinsonism deteriorated gradually. She also developed syncope orthostatic hypotension. In April of 1998, she developed intracerebral hemorrhage and was admitted again on April 19, 1998. She was unable to stand and showed marked akinesia and rigidity. She was in stage V of Hoehn and Yahr. Her cranial CT scan revealed bilateral high-density lesions in the posterior parietal lobes. She developed dysphagia for which she required gastrostomy. She was transferred to another hospital but her clinical condition deteriorated further. On December 22, 1999, she developed fever and dyspnea and was admitted to our service again. She developed cardial arrest at the emergency room from hypoxia. She was resuscitated; however, she was comatose with loss of brain stem reflexes. Later on she developed generalized myoclonus. She developed cardiac arrest and pronounced dead on December 28, 1999. The patient was discussed in a neurological CPC. The chief discussant arrived at the conclusion that the patient had striatonigral degeneration because of poor response to levodopa in the later course, autonomic failures, and MRI changes. Some other participants thought that the patient had a form of familial Parkinson's disease. Opinions were divided into these two possibilities. Post-mortem examination revealed that the substantia nigra showed intense neuronal loss and gliosis, however, no Lewy bodies were seen. In addition, intracytoplasmic inclusions were seen in oligodendrocytes. The putamen was markedly atrophic in its posterior part with marked gliosis and neuronal loss. The ventromedial part of the pontine nucleus also showed neuronal loss and intracytoplasmic glial inclusions. Pathologic diagnosis was multiple system atrophy. In the parietal lobe, an arteriovenous malformation with bleeding was noted. This is very unique case. Although her mother had Lewy body-positive Parkinson's disease, the patient had Lewy body-negative multiple system atrophy with a-synuclein-positive glial inclusions. Whether this is just a coincidental occurrence or the presence of a genetic load for Parkinson's disease might triggered her multiple system atrophy is an interesting question to be answered in future.
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PMID:[A-56-year-old woman with parkinsonism, whose mother had Parkinson's disease]. 1142 77

Orthostatic tremor (OT) is not an uncommon symptom in various neurodegenerative diseases. However, the nature and pathophysiology of OT involve a complex network of tremors and dopaminergic pathways. We assessed patients who complained of prominent leg tremors described as "shaky leg." We analyzed their characteristics and evaluated them with neuroimaging and electrophysiological tools. A total of 23 patients who experienced an uncomfortable symptom of leg tremor were retrospectively enrolled from April 2014 to October 2019. Previous medical history, brain MRI, and surface electromyography (EMG) data were analyzed. The [18F]-FP-CIT brain positron emission tomography (PET) and the Unified Parkinson's Disease Rating Scale (UPDRS) were assessed for patients who showed parkinsonism. The causes of OT varied: parkinsonism (n = 5), idiopathic causes (n = 4), secondary causes (n = 3, trauma, brain lesion, arteriovenous malformation), drug reactions (n = 3, valproate, perphenazine, haloperidol), other neurological disorders (n = 5, essential tremor, dystonia, restless leg syndrome, REM sleep behavior disorder, dementia), alcohol withdrawal (n = 1), functional movement disorder (n = 1), and an unknown cause (n = 1). The frequency range varied (2.6-15 Hz) and according to the new consensus statement on the classification of OT, 4 patients had primary OT, 2 had "primary OT plus," 12 had slow OT, and 5 had orthostatic myoclonus. The prognosis associated with the use of medication was generally poor; however, clonazepam and levodopa were the most effective drugs. In conclusion, we found that different types of OT and orthostatic myoclonus were diagnosed by electrophysiological evaluation and neuroimaging tools even if they showed the same symptoms as "shaky leg." In addition, it is possible to roughly estimate the response to medication according to the type of OT and the cause. To clarify the pathophysiology of OT, a large number of longitudinal cohort studies and detailed neuroimaging and electrophysiological evaluations are needed.
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PMID:What Shall We Do for the Patients with Shaky Leg Syndrome? A Review of 23 Patients. 3291 73