Handbook of clinical neurology
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The embryologic development of the cerebellum extends over a long time period, thus making it vulnerable to a broad spectrum of malformations and disruptions. Knowledge of the main steps of fetal posterior fossa development; the normal imaging patterns at different stages of embryogenesis; the large spectrum of cerebellar malformations; and their clinical presentations enables diagnosis and precise counseling of parents. Sonography is the most important imaging method for the screening of cerebellar malformations since it is noninvasive, widely available, and safe for both mother and child. ⋯ Good-quality images have been obtained thanks to the implementation of fast and ultrafast MRI sequences. Fetal MRI has higher-contrast resolution than prenatal sonography and may contribute to the differentiation of normal from abnormal tissue. Both prenatal neurosonography and fetal MRI enable accurate prenatal diagnosis of most posterior fossa anomalies.
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Sporadic adult-onset ataxia (SAOA) is a nongenetic neurodegenerative disorder of the cerebellum of unknown cause which manifests with progressive ataxia. It is distinguished from hereditary ataxias and from acquired ataxias. SAOA also needs to be differentiated from multiple system atrophy of cerebellar type (MSA-C). ⋯ Brain imaging typically shows isolated cerebellar atrophy. Nerve conduction studies provide evidence for polyneuropathy in about one-third of SAOA patients. As the etiology and pathogenesis of SAOA are unknown, there is no specific treatment approach to this condition.
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Chronic traumatic encephalopathy (CTE) is a neurodegenerative tauopathy associated with repetitive head trauma, including concussion and subconcussion. CTE was first recognized in boxers nearly a century ago as "dementia pugilistica" or "punch drunk," but has been recently identified in contact sports athletes (including American football, ice hockey, soccer, baseball, rugby, boxing, and wrestling) and military veterans exposed to blast. Similar to many other neurodegenerative diseases, CTE is diagnosed conclusively only by neuropathologic examination of brain tissue. ⋯ A preliminary study showed that inflammatory cytokines were elevated in the brain tissue and cerebrospinal fluid of individuals with pathologically confirmed CTE compared to controls and individuals with Alzheimer disease, which may some day be useful in diagnosis of CTE during life. Although many fundamental questions remain to be answered regarding CTE, postmortem analysis of tissue from brain donors and tissue-based research have accelerated and expanded our current understanding of CTE and its pathogenesis. Guided by the neuropathologic findings, current research efforts are underway to develop biomarkers to diagnose CTE and effective ways to treat the disorder during life.
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Accidental hypothermia causes profound changes to the body's physiology. After an initial burst of agitation (e.g., 36-37°C), vital functions will slow down with further cooling, until they vanish (e.g. <20-25°C). Thus, a deeply hypothermic person may appear dead, but may still be able to be resuscitated if treated correctly. ⋯ Intermittent CPR may be appropriate in hypothermic arrest when continuous CPR is impossible. Modern postresuscitation care should be implemented following hypothermic arrest. Structured protocols should be in place to optimize prehospital triage, transport, and treatment as well as in-hospital management, including detailed criteria and protocols for the use of ECLS and postresuscitation care.
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Genetics of migraine has recently undergone a major shift, moving in the space of a few years from having only a few known genes for rare Mendelian forms to 47 known common variant loci affecting the susceptibility of the common forms of migraine. This has largely been achieved by rapidly increasing sample sizes for genomewide association studies (GWAS), soon to be followed by the first wave of large-scale exome-sequencing studies. ⋯ Heritability-based analyses are demonstrating strong links between migraine and other neuropsychiatric disorders and brain phenotypes, highlighting genetic links between migraine and major depressive disorder and attention-deficit hyperactivity disorder, among others. These recent successes in migraine genetics are starting to be mature enough to provide robust evidence of specific quantifiable genetic factors in common migraine.