Doença cerebrovascular em adultos com anemia falciforme: avaliação pelo doppler transcranianos e ressonância magnética
Arquivos
Data
2005
Autores
Silva, Gisele Sampaio 
Orientadores
Massaro, Ayrton Roberto
Tipo
Tese de doutorado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Objetivos
: Apesar das crianças serem as
principais acometidas pela doença
cerebrovascular na doença falciforme, adulto
s falcêmicos também apresentam risco
elevado quando comparados à população geral. O
Doppler transcraniano é o principal
exame para determinação do risco de eventos
cerebrovasculares em crianças com
anemia falciforme. Alterações na ressonânc
ia magnética de encéfalo também foram
descritas em até 44% das crianças com anem
ia falciforme em estudos recentes. Os
objetivos do presente estudo foram: det
erminar o papel do Doppler transcraniano na
identificação da doença cerebrovascular de pac
ientes adultos com anemia falciforme;
estudar a freqüência de alterações na
ressonância magnética de encéfalo e na
angiorressonância das artérias intracranianas
desses pacientes; verificar a existência
de correlação entre as alterações obs
ervadas na ressonância magnética e as
velocidades de fluxo sangüíneo obtidas no Doppler transcraniano.
Métodos:
Todos os
pacientes com idade superior a 16 anos ac
ompanhados no ambulatório de hematologia
da UNIFESP-EPM com o diagnóstico de hem
oglobinopatia SS e o mesmo número de
voluntários saudáveis pareados por sexo e i
dade foram avaliados. Os pacientes foram
submetidos ao Doppler transcr
aniano, à entrevista e exame
clínico, à coleta de um
hemograma e à ressonância de encéfalo
e angiorressonância das artérias
intracranianas, que foram avaliadas por doi
s neurorradiologistas que desconheciam os
resultados do Doppler transcraniano. Os vo
luntários saudáveis foram avaliados com
Doppler transcraniano, entrevista e exame cl
ínico e coleta de um hemograma. As
lesões na ressonância de encéfalo foram classi
ficadas em leucoencefalopatia, atrofia,
encefalomalácia e infartos lacunares.
Critérios de anormalidade na angiorressonância
incluíram estenoses ou oclusões
arteriais e tortuosidade vascular.
Resultados: Cinqüenta e seis pacientes e o mesmo
número de voluntários saudáveis foram
submetidos ao Doppler transcraniano. As
velocidades de fluxo sangüíneo em ambos os
grupos se correlacionaram inversamente com
o hematócrito. As velocidades de fluxo
encontradas em pacientes com anemia falcifo
rme foram significativamente maiores do
que em voluntários saudáveis. Cinqüenta paci
entes realizaram re
ssonância de encéfalo
e angiorressonância das artérias intracr
anianas. A freqüência global de alterações
observadas na ressonância de encéfalo ati
ngiu 60%. Leucoencefalopatia foi o achado
mais comum (48%). A angiorressonância das ar
térias intracranianas foi anormal em
72% dos pacientes e estenoses intrac
ranianas foram encontradas em 16% dos
exames. Pacientes com estenoses intr
acranianas e aqueles com lacunas na
ressonância de encéfalo apresentaram veloci
dades de fluxo significativamente maiores
(p=0,01 e p=0,03 respectivamente).
Conclusões:
As velocidades de fluxo sangüíneo
no Doppler transcraniano de adultos com anemia
falciforme são significativamente
maiores do que as observadas em adultos
saudáveis e menores
do que as descritas
em crianças falcêmicas. Alterações
na ressonância de encéfalo e angiorressonância
das artérias intracranianas em adultos com
anemia falciforme são mais freqüentes do
que as descritas em crianças, confirm
ando uma tendência de aumento das lesões
silenciosas em função da idade identificada em
estudos mais recentes. As velocidades
associadas a estenoses em adultos falcêmic
os são menores do que as descritas na
população pediátrica. O Doppler transcr
aniano e a ressonância de encéfalo são
métodos importantes e complementares
na avaliação da doença cerebrovascular do
paciente com anemia falciforme e apresent
am freqüências de alterações e padrões de
anormalidades distintos entre adultos e crianças falcêmicas.
Background : Stroke occurs in 11% of child ren with hemoglobin SS before the age of twenty years and it is also a major cause of morbidity in adults, with an incidence that is at least ten times greater than for Afric an Americans without sickle cell disease (SCD). Transcranial Doppler (TCD) is the key test in determining the need for prophylactic blood transfusion to prevent stroke in ch ildren with sickle cell disease (SCD). Brain imaging abnormalities were reported in up to 44% of children with sickle cell disease (SCD). Objectives : Our objective was to investigate the pattern of TCD velocities, the frequency of brain MRI abnormalities and its co rrelation with TCD velocities in adult patients with SCD. Patients and method : All patients with hemoglobin SS di sease, 16 years of age or older followed in the hematol ogy outpatient clinic of our university hospital were evaluated. TCD exams, a clin ical interview and a complete blood count were performed at the same day. Brain magnetic res onance imaging (MRI) and magnetic resonance angiography (MRA) were evaluated by two neuroradiologist s who were unaware of the TCD results. Lesions were broadly defined to include lacunar infarction, encephalomalacia, leucoencephalopathy or atr ophy. Criteria of abnormality by using MRA included stenosis or apparent occlusion of any vessel and arterial tortuosity. Results : TCD was performed in 56 patients and 56 controls. Velocities in SCD adults were higher t han in controls and negatively correlated to hematocrit in both groups. The overa ll frequency of lacunar infarction, encephalomalacia, leucoencephalopathy or atrophy was 60%. Leukoencephalopathy was the most common finding (48%). MRA was abnormal in 36 patients (72%) and intracranial stenoses were observed in 16% . Patients with MCA or ICA intracranial 98 stenosis and those with lacunar infarctions had significantly higher maxFV (p=0.01 and p=0.03 respectively). Conclusions: The pattern of TCD velocities in adul ts with SCD is different from that described in children. Brain imaging abno rmalities in SCD adult patients are more frequent in adults than in t he pediatric population. MRI and MRA findings correlated with TCD changes, but velocities associated to intr acranial stenosis in adults are lower than in children. TCD and MRI are important met hods in the evaluation of SCD patients and present different patterns and frequency of abnormalities in children and adul
Background : Stroke occurs in 11% of child ren with hemoglobin SS before the age of twenty years and it is also a major cause of morbidity in adults, with an incidence that is at least ten times greater than for Afric an Americans without sickle cell disease (SCD). Transcranial Doppler (TCD) is the key test in determining the need for prophylactic blood transfusion to prevent stroke in ch ildren with sickle cell disease (SCD). Brain imaging abnormalities were reported in up to 44% of children with sickle cell disease (SCD). Objectives : Our objective was to investigate the pattern of TCD velocities, the frequency of brain MRI abnormalities and its co rrelation with TCD velocities in adult patients with SCD. Patients and method : All patients with hemoglobin SS di sease, 16 years of age or older followed in the hematol ogy outpatient clinic of our university hospital were evaluated. TCD exams, a clin ical interview and a complete blood count were performed at the same day. Brain magnetic res onance imaging (MRI) and magnetic resonance angiography (MRA) were evaluated by two neuroradiologist s who were unaware of the TCD results. Lesions were broadly defined to include lacunar infarction, encephalomalacia, leucoencephalopathy or atr ophy. Criteria of abnormality by using MRA included stenosis or apparent occlusion of any vessel and arterial tortuosity. Results : TCD was performed in 56 patients and 56 controls. Velocities in SCD adults were higher t han in controls and negatively correlated to hematocrit in both groups. The overa ll frequency of lacunar infarction, encephalomalacia, leucoencephalopathy or atrophy was 60%. Leukoencephalopathy was the most common finding (48%). MRA was abnormal in 36 patients (72%) and intracranial stenoses were observed in 16% . Patients with MCA or ICA intracranial 98 stenosis and those with lacunar infarctions had significantly higher maxFV (p=0.01 and p=0.03 respectively). Conclusions: The pattern of TCD velocities in adul ts with SCD is different from that described in children. Brain imaging abno rmalities in SCD adult patients are more frequent in adults than in t he pediatric population. MRI and MRA findings correlated with TCD changes, but velocities associated to intr acranial stenosis in adults are lower than in children. TCD and MRI are important met hods in the evaluation of SCD patients and present different patterns and frequency of abnormalities in children and adul
Descrição
Citação
SILVA, Gisele Sampaio. Doença cerebrovascular em adultos com anemia falciforme: avaliação pelo Doppler transcraniano e ressonância magnética. 2005. 120 f. Tese (Doutorado) - Escola Paulista de Medicina, Universidade Federal de São Paulo. São Paulo, 2005.