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What is Which of the following statement is true about external haemorrhoids? and explain in detail?
It presents as a suddenonset, olive-shaped, painful blue subcutaneous swelling at the anal margin and is usually consequent upon straining at stool, coughing or lifting a heavy weight .The thrombosis is usually situated in a lateral region of the anal margin. If the patient presents within the first 48 hours the clot may be evacuated under local anaesthesia. Ref: Bailey & Love&;s Sho Practice of Surgery,E25,Page-1259