Lacunar Infarction in Type 2 Diabetes Is Associated with an Elevated Intracranial Arterial Pulsatility Index

PURPOSE: The arterial pulsatility index (PI) is measured by transcranial Doppler ultrasonography (TCD) and is postulated to reflect the vascular resistance distal to the artery being examined. An increased PI of the intracranial artery is often reported with diabetes mellitus (DM), old age, hypertension, intracranial hypertension, vascular dementia, and small artery disease. Microvascular complication of DM, which may contribute to cerebral infarction, involves the small perforating artery and may influence the PI of the proximal artery. MATERIALS AND METHODS: We performed a TCD examination in patients with type 2 DM with acute lacunar infarction (DML, n=35), type 2 DM without cerebral infarction (DMO, n=69), and in control cases with no DM or cerebral infarction (control group, n=41). We then compared the TCD findings among these groups. RESULTS: The PI was significantly higher in the DML and DMO groups than in the control group (1.05, 0.93, 0.73. respectively, for the right middle cerebral artery; 1.04, 0.90, 0.73, respectively, for the left middle cerebral artery; 0.97, 0.89, 0.70, respectively, for the basilar artery). The PI was also significantly higher in the DML group than in the DMO group for both middle cerebral arteries. The flow velocity was comparable among the three groups. CONCLUSION: The elevated PI of the intracranial arteries may reflect diabetic cerebral microvascular complications. The PI measurement using TCD may be a useful predictor of lacunar infarction in type 2 DM patients.

Changes of blood flow velocity indicating mechanical compression of the vertebral arteries during rotation of the head in the normal human measured with transcranial doppler sonography

Estudos anatômicos, angiografias em voluntários normais e relatos clínicos de pacientes com sintomas atestam o fato de que o fluxo sanguíneo através das artérias vertebrais (VA's) é parcialmente obstruido ao nível da articulaçäo atlanto-axial (C1-C2) durante a rotaçäo da cabeça. Variaçöes anatômicas as artérias cerebrais basais, trauma e outros processos patológicos têm sido relacionados à compressäo mecânica fisiológica das VA's na patogenia de insuficiência vertebrobasilar. No presente estudo, as alteraçöes dinâmicas da velocidade do fluxo sanguíneo (BFV) nas artérias do sistema vertebrobasilar, provocadas por rotaçäo da cabeça em voluntários adultos normais, säo medidas com Doppler trnscraniano (TCD) das VA's (segmento intracraniano V4) e artéria basilar (BA). Em 8 indivíduos o estudo foi repetido com um instrumento de TCD de dois canais, permitindo o estudo simultâneo das VA's (grupo 2). A artéria basilar foi examinada com a técnica transforaminal e as VA's com o método transoccipital. Resultados: A BFV na BA e VA's diminuiu de modo significante durante rotaçäo da cabeça no grupo I, idenpendentemente do lado da rotaçäo (p ó 0.001). A mais acentuada diminuiçäo do BFV ocorreu na VA do lado direito durante rotaçäo episilateral (-18 por cento)...