RESUMO
Chronic daily headaches (CDH) consist of episodes of head pain occurring daily; more than 15 days each month; often associated with a history of migraine, with or without aura; or with a history of tension-type headaches occurring alone or both occurring together. Chronic daily headaches are frequently associated with rebound headaches after ergotamine, barbiturate, caffeine, and analgesic abuse. We previously reported that migraineurs with typical intermittent headaches exhibited excessive cerebral cortical vasodilation after oral acetazolamide which usually precipitated and reproduced their typical headaches. In the present study, cerebral vasodilator responses were tested by measuring changes in local cerebral blood flow (Delta LCBF) utilizing xenon-contrasted CT scanning, before and after oral administration of 14.3 mg/kg of acetazolamide, in 11 patients with CDH. The results were compared with 12 age-matched typical migraineurs, with and without aura, who had a history of migraine attacks occurring at intervals of 1 month or longer. Global and subcortical gray and white matter Delta LCBFs were quantitated and compared between both groups. After acetazolamide, Delta LCBF increased in cortical gray matter by 11.8% among patients with CDH and by 16.7% among migraineurs, with no significant differences between groups. Typical migraine attacks were provoked by acetazolamide in 9 patients (82%) with CDH and in 11 (92%) migraineurs with intermittent headaches. These observations are taken as evidence that at least 82% of patients with CDH have transformed migraine as judged by the provocation by acetazolamide of typical migraine attacks associated with excessive Delta LCBF increases. Serotonin agonists should be considered in the treatment of CDH to avoid ergotamine, caffeine, barbiturate, and analgesic abuse.
Assuntos
Transtornos da Cefaleia/etiologia , Transtornos da Cefaleia/fisiopatologia , Enxaqueca com Aura/complicações , Enxaqueca sem Aura/complicações , Acetazolamida/farmacologia , Adulto , Idoso , Inibidores da Anidrase Carbônica/farmacologia , Cerebelo/irrigação sanguínea , Feminino , Cefaleia/diagnóstico , Cefaleia/etiologia , Cefaleia/fisiopatologia , Transtornos da Cefaleia/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Enxaqueca com Aura/diagnóstico , Enxaqueca com Aura/fisiopatologia , Enxaqueca sem Aura/diagnóstico , Enxaqueca sem Aura/fisiopatologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasodilatação/efeitos dos fármacosRESUMO
Migraine headaches usually decrease in frequency and severity and often cease during advancing age. Occasionally, migraineurs report late-life migrainous accompaniments, i.e., auras without headache, particularly when typical migraine attacks terminate or diminish following major or minor strokes, at which time the auras may become atypical. Clinical observations such as these suggest that degenerative cerebrovascular changes accompanying aging may modify the course of migraine headaches particularly those with aura. To test this hypothesis, we quantitated age-related changes in cerebral vasodilator capacitance by measuring local cerebral blood flow utilizing xenon contrast computed tomography (CT) scanning before and after oral administration of the pharmacological cerebral vasodilator, acetazolamide (Diamox). Measurements were compared among 27 normal volunteers without headache (aged 24-94 years; mean age 61.1 +/- 17.6) and 37 carefully categorized groups of migraine patients (aged 27-83 years; mean age 59.4 +/- 12.4). The normals comprised Group A. Migraineurs were divided into two subgroups: Group B consisted of 27 migraineurs with and without aura who continued to suffer from incapacitating and frequent headaches and Group C consisted of 10 migraineurs who no longer suffered from severe and frequent headaches, two of whom still complained of atypical auras of the "late-life migrainous accompaniments" type. Cerebral vasodilator capacitance significantly declined with advancing age among normals and the two groups of migraineurs, confirming the development of age-related cerebrovascular diseases. Global CBF increases after Diamox in Group B (with persistent and severe migraine), were significantly greater compared with normals without headache, and with Group C consisting of migraineurs whose headaches had decreased, subsided, or become replaced by late-life migrainous accompaniments (Group C). Results establish that cerebrovasodilator capacitance declines with advancing age, probably due to progressive cerebral atherosclerosis, since these declines were accentuated by risk factors for stroke, particularly TIAs or documented lacunar infarcts by CT. Progressive impairments of cerebral vasodilator capacitance among migraineurs were associated with: (i) reductions in frequency and severity of migrainous cephalalgia and (ii) appearance of late-life migrainous accompaniments.
Assuntos
Transtornos Cerebrovasculares/fisiopatologia , Transtornos de Enxaqueca/fisiopatologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/irrigação sanguínea , Infarto Cerebral/diagnóstico , Infarto Cerebral/fisiopatologia , Transtornos Cerebrovasculares/diagnóstico , Feminino , Humanos , Arteriosclerose Intracraniana/diagnóstico , Arteriosclerose Intracraniana/fisiopatologia , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/diagnóstico , Medição da Dor , Tomografia Computadorizada por Raios X , Vasodilatação/fisiologiaRESUMO
It is concluded that the most important determinants for cerebral neurodegenerative changes and cognitive decline during aging are neuronal shrinkage and/or loss, which are accelerated by certain risk factors: e.g. TIAs, hypertension, heart disease, hyperlipidemia, smoking, heavy alcohol consumption, male gender, low educational status, family history of cerebrovascular disease and absence of estrogen replacement therapy among women. Some of these risk factors are remediable by therapeutic interventions, including prevention of TIAs and medications that control hypertension, heart disease, hyperlipidemia and estrogen replacement in postmenopausal women, as well as abstention from abuse of tobacco and alcohol. Cerebral neurodegenerative changes measured by neuroimaging appear to be premorbid markers for depleted neuronal and synaptic reserves which predispose to the onset of dementias of both VAD and DAT types. Normal subjects at risk for cognitive decline include those with TIAs, hypertension and heart disease since these risk factors measurably accelerate cerebral atrophy, ventricular enlargement, leukoaraiosis, and decline in cortical perfusion.
Assuntos
Atrofia/patologia , Encéfalo/patologia , Demência/patologia , Degeneração Neural/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Estudos de Casos e Controles , Circulação Cerebrovascular/fisiologia , Transtornos Cognitivos/diagnóstico , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVES: Thirty seven vascular dementia (VAD) patients were categorized into eight subtypes based on clinical, radiological, and pathogenetic features. Cerebral vasodilator responses to acetazolamide were then compared with age-matched normal controls and stroke patients without dementia. METHODS: VAD results were compared with 42 normals and 19 cognitively intact stroke patients. Regional cerebral vasodilator responses were quantitated utilizing xenon contrasted computed tomography measures of local cerebral blood flow (LCBF) before and after oral administration of acetazolamide. LCBF changes (DeltaLCBF) before and after acetazolamide were calculated within cortical and subcortical, gray and white matter. Clinical VAD subtypes were: type 1, multi-infarct dementia (MID); type 2, strategically placed infarcts; type 3, subcortical lacunar infarcts; type 4, Binswanger's subcortical arteriosclerotic leukoencephalopathy; type 5, subcortical infarctions due to cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), inflammatory angitis, or antiphospholipid antibodies; type 6, admixtures of above types; type 7, cerebral hemorrhagic lesions; and type 8, VAD combined with Alzheimer's disease (DAT). The group with subcortical VAD comprised types 3-5. The group with cortical VAD comprised the remainder (types 1, 2, and 6-8). Cerebral vasodilator responses were also compared between these two main groups. RESULTS: Cerebral vasodilator responses identified differences between the two main groups of VAD patients, those with cortical and those with subcortical dementia. Leukoaraiosis was measurably greater in subcortical VAD compared with cortical VAD. Among subcortical VAD patients, cortical LCBF increases after administration of acetazolamide were greater compared with cortical VAD and with normal controls. CONCLUSIONS: Cognitive impairments in subcortical VAD are attributable to cortical disconnection syndromes. This concept is supported by reduced perfusion in deactivated cortex. In patients with subcortical VAD, deactivated cortical LCBF becomes promptly activated by acetazolamide resulting in marked cortical LCBF increases. Leukoaraiosis is greater among VAD patients and leukoaraiosis contributes to cortical disconnections, confirmed by excessive cortical vasodilator responses to acetazolamide.
RESUMO
Vascular dementia (VAD) is considered to be the second most common cause of dementia in Europe and the US. In Asia and many developing countries, it is more common than dementia of the Alzheimer's type (DAT). VAD is the most preventable form of dementia associated with later life. The pathogenesis of VAD is multifactorial, and it represents a heterogeneous, not a homogeneous, clinical entity. Classification of VAD by pathogenesis is important for its prevention and treatment. Control of the risk factors for VAD reduces its incidence and stabilises or improves cognitive performance following stroke. Proper diagnostic evaluation of VAD requires: (i) a well defined quantitative assessment of the cognitive deficits present; (ii) assessment of risk factors for stroke; (iii) identification of cerebral vascular lesions by history, neurological examination and neuroimaging; (iv) exclusion of other causes of dementia; (v) establishment of a positive diagnosis of possible, probable or definite VAD versus DAT or mixed VAD/DAT; and (vi) identification of the temporal relationship between cognitive deficits and cerebral vascular lesions. VAD can be subdivided into 8 major types, as follows: (i) multi-infarct dementia secondary to large cerebral emboli [type 1]; (ii) strategically placed infarctions causing dementia [type 2]; (iii) multiple subcortical lacunar lesions secondary to atherosclerosis or degenerative arteriolar changes [type 3]; (iv) Binswanger's disease (arteriosclerotic subcortical leukoencephalopathy) [type 4]; (v) mixtures of types 1, 2 and 3 [type 5]; (vi) haemorrhagic lesions causing dementia [type 6]; (vii) subcortical dementia secondary to hereditary factors (type 7); and (viii) mixtures of DAT and VAD (type 8). Treatment is dictated by the pathogenetic subtype of VAD that is present.
Assuntos
Demência Vascular , Demência Vascular/classificação , Demência Vascular/diagnóstico , Demência Vascular/etiologia , Demência Vascular/terapia , Humanos , Fatores de RiscoAssuntos
Bloqueadores dos Canais de Cálcio/uso terapêutico , Transtornos Cerebrovasculares/tratamento farmacológico , Nimodipina/uso terapêutico , Hemorragia Subaracnóidea/tratamento farmacológico , Vasodilatadores/uso terapêutico , Adulto , Bloqueadores dos Canais de Cálcio/farmacologia , Transtornos Cerebrovasculares/cirurgia , Terapia Combinada , Humanos , Nimodipina/farmacologia , Hemorragia Subaracnóidea/cirurgia , Vasodilatadores/farmacologiaRESUMO
Sport-latent somatosensory evoked potentials (SLSEP) were used to objectivize the time course of clinical changes after surgery for meningomyeloradiculosis in the late period of spinal traumatic injury. New evidence was obtained for the correlation between the changes in SLSEP with displacement from the lower thoracic and lumbar regions of the spine and these in the clinical picture of the disease (both neurological and urological) following spinal injury.