tailieunhanh - Vascular Surgery - part 5

Từ điều tra mô học của 76 trường hợp khám nghiệm tử thi thu thập trong vòng 16 năm qua, Nasu (1977) phân loại tổn thương này histopathologically thành ba loại: loại viêm u hạt, loại viêm lan tỏa sản xuất, và loại xơ. Loại u hạt Viêm (28%) u hạt, | 478 Part VI Chronic Arterial Occlusions of the Lower Extremities is considered to be approximately 3000 and the annual increase of new cases is estimated to be about 100. Pathology From the histologic investigation of 76 autopsy cases collected over the last 16 years Nasu 1977 classified this lesion histopathologically into three types granulomatous inflammation type diffuse productive inflammation type and fibrosis type. Granulomatous Inflammation Type 28 Granulomas often accompanied by Langerhans giant cells and foreign body giant cells are formed with or without the presence of small necrotic foci and microabscesses. Diffuse Productive Inflammation Type 14 Diffuse infiltration of lymphocytes and plasma cells along with proliferation of connective tissue and new growth of blood vessels is seen in the media. A few solitary giant cells are found scattered in rare cases. Fibrosis Type 58 This type was observed in a large majority of cases and was thought to be the sequela of the inflammatory changes. The severe fibrosis occurred chiefly in the media because of scar formation after granulomatous and productive inflammation. Fibrosis of the adventitia is thought to be a protective reaction against passive distention due to diminished elasticity of the weakened media. Secondary fibrosis was also detected in the intima and its severity depended mostly on the duration of the disease process. In the autopsy cases pulmonary artery involvement was detected in 45 . Pathophysiology Clinical pictures of Takayasu s arteritis are extremely variable because of the distribution of the arterial lesions. There has not yet been a definite classification of the disease however we have classified it into three types according to hemodynamic characteristics Fig. . Typel A classic pulseless disease that manifests hypotension of the head and upper extremities. Dizziness syncope impaired vision and claudication of the upper extremity are the commonly noted chief complaints. Type 2 .