optic nerve injury decompression

The causes of optic nerve damage in closed craniocerebral injury are: 1 due to optic nerve turbulence or traction injury; 2 due to fractures of the optic canal, anterior crest or dome directly damage the optic nerve; 3 optic canal hematoma The pressure of effusion is also a common cause of damage; 4 after the injury, the blood supply to the optic nerve is affected, and the occurrence of blood supply or infarction can also cause optic nerve function disorder. Treating diseases: optic nerve diseases Indication 1. CT and/or MRI suggest that the anterior cranial fossa fracture involves the optic canal, causing the optic nerve to be compressed due to fracture or bleeding, or swollen deformation. 2, the injured eye still has a light sensation, GCS score > 12 points, younger age, non-surgical treatment is not effective. 3, visual impairment after injury, is a progressive development. 4, the large area of the upper wall collapsed caused by visual impairment. 5, although the eye is completely blind after the injury, but after treatment with hormones and vasodilators, there is a recovery of light. 6, the brain injury is heavier, and there is optic nerve damage, in the forehead craniotomy for the treatment of brain injury or removal of hematoma, while under the premise of not affecting the treatment of brain injury, the decompression of the nerve canal. The timing of the operation should be as early as possible, preferably within 1 week after the injury, and no more than 2 to 3 weeks at the latest. Contraindications 1. Immediately after the injury, blindness is confirmed by pupillary reaction and VEP examination, and it is confirmed that the patient is completely blind and the non-surgical therapy is invalid. 2, in addition to optic nerve damage, brain injury is heavier, GCS is less than 12 points, should first save lives, and then consider whether to open the optic canal decompression. 3, elderly patients, although not completely blind, but it is estimated that postoperative visual acuity can not restore hope, or have other serious chronic diseases. Preoperative preparation 1. Prepare the skin. Wash the head with soap and water 1 day before the operation. Shave the hair on the morning of the operation. 2. Fasting in the morning of surgery. It can be enema in the evening before surgery, but when the intracranial pressure is increased, the enema should be removed to avoid sudden deterioration of the condition. 3, can give phenobarbital 0.1g orally before surgery to ensure a quiet rest. One hour before the operation, 0.1 g of phenobarbital, 0.4 mg of atropine or 0.3 mg of scopolamine were intramuscularly injected. Surgical procedure 1, scalp incision Most of the forehead hairline internal coronal incision is used, and the frontal unilateral incision can also be used. The flap is turned over to the upper edge of the iliac crest. 2, bone flap formation Make a bone flap on the unilateral (affected side) forehead. The lower edge of the bone flap is close to the eyebrow arch, which is convenient for lifting the frontal lobe, but to avoid opening the frontal sinus; if the frontal sinus is accidentally opened, it should be routinely treated to avoid cerebrospinal fluid leakage after surgery. 3, cut the dura mater The dura mater is parallel to the upper edge of the iliac crest. The medial and lateral ends of the incision are cut into two auxiliary incisions in the up-down direction to form an "H"-shaped dura mater. The dura mater below the incision is sutured on the periosteum. 4, revealing the anterior cranial fossa Use the brain pressure plate to gently lift the underside of the frontal lobe, tear the arachnoid membrane on the lateral fissure surface on the outside, suck out the cerebrospinal fluid, and gradually deepen. Do not rush too fast, wait for the cerebrospinal fluid to be sucked out to make the brain automatically retract, until the optic nerve and anterior bed of the surgical side are exposed. Sudden. In this process, try to protect the olfactory nerve. If it is not enough to hinder the operation or the exposure is insufficient, the olfactory nerve can be cut off. The frontal lobe is protected with a cotton pad and fixed with a serpentine retractor to fully expose the underside of the cranial anterior fossa to the field. 5, remove the upper wall of the optic canal The dura mater on the upper wall of the optic canal is cut along the direction of the optic nerve, and an auxiliary transverse incision is made on the upper end of the optic canal to peel the dura mater left and right to expose the bone on the upper wall of the optic canal. The upper wall of the tube fully exposes the optic nerve sheath. 6, open the optic nerve sheath According to the condition of the optic nerve injury, only the dura mater at the inner end of the neural tube may be cut and decompressed. If the decompression is insufficient, the optic nerve sheath may be cut and decompressed. 7, the skull After flushing the field with saline, carefully observe, after the hemostasis is complete, the dura mater is tightly sutured, the bone flap is restored, and the scalp is sutured. complication 1, when the upper frontal lobe reveals the anterior cranial fossa, such as the frontal lobe contusion and heavier, postoperative hematoma in the brain, requiring secondary surgery to remove. 2, due to the opening of the paranasal sinus during surgery, not well treated, postoperative cerebrospinal fluid rhinorrhea. Others are the same as the common complications after general craniotomy.