Craniotomy sounds scary, but in fact, craniotomy is very common in neurosurgery, such as the occurrence of serious cranial injury, or patients suffering from certain craniosynostosis, etc., may have to be treated through craniotomy. In addition, if the patient has a rising intracranial pressure during the craniotomy, it is necessary to perform decompression surgery with a large bone flap in a timely manner. The reason for decompression of the large bone flap is that the procedure has the advantage of wide exposure and opening the limited space in the skull, so that the surgeon can decompress and stop the bleeding of the patient’s intracranial tissues under direct visualization, making the patient’s situation less dangerous. Is cranial decompression debridement surgery risky? The procedure of decompression of the large bone flap is very strict. Generally, as long as there is no postoperative infection and no further bleeding, there is not much risk, so the safety is still quite high. However, because decompression of the large bone flap requires opening the skull window, it is inevitable that cranial defects will remain after surgery. Of course, cranial defects should not be ignored, because the cranial bone is equivalent to a protective membrane of the brain, and without the protection of the cranial bone, the operation of all intracranial life activities will be affected. In order to avoid more damage caused by cranial defects, it is recommended that patients should undergo cranial repair surgery about 3 months after decompression of the large bone flap.