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What is Which of the following describes the Westermark sign in Pulmonary Thromboembolism? and explain in detail?
Sign in Pulmonary Thromboembolism: * Fleischner sign: enlarged pulmonary aery * Hampton hump:peripheral wedge of airspace opacity and implies lung infarction * Westermark sign:regional oligemia and highest positive predictive value. * Palla sign: enlarged right descending pulmonary aery * Chang sign: dilated right descending pulmonary aery with sudden cut-of