Definition: Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.
Input: Question: Is subcutaneous injection of liquid and foamed polidocanol : extravasation responsible for skin necrosis during reticular and spider vein sclerotherapy?
Answer: This experimental study shows that extravasation of polidocal in usual circumstances of sclerotherapy of spider and reticular veins cannot be a significant cause of cutaneous necrosis rarely observed in this setting. It is particularly true for the foamed polidocanol where 1% strength seems safe if injected extravascularly in volumes up to 0.5 mL.
Output:
no