Objective To summarize the clinical efficacy of digital contouring cranioplasty in 26 patients with large cranial defects. Methods We retrospectively analyzed 26 cases of large cranial defects and performed CT ultrathin scanning and three-dimensional reconstruction before digital cranioplasty, and sent the data to the titanium plate manufacturers through the Internet, according to which the two-dimensional titanium plates were processed and produced, and the digitally shaped two-dimensional titanium plate cranioplasty materials could be obtained in about 2 days and implanted in the surgery. The results of all cases of digital molding cranioplasty after molding are very satisfactory, postoperative complications include: subcutaneous blood accumulation in 2 cases (7.6), after conservative treatment hematoma absorption. Subcutaneous effusion was found in 3 cases (11.5), which were cured by puncture aspiration and pressure dressing. There were no other complications. In the follow-up of cranioplasty more than 6 months to 1 year after the operation, there was no infection, rejection, exsanguination, displacement or collapse in 26 cases. Conclusion For patients with large cranial defects using titanium mesh as a repair material, digital shaping technology should be used. 1, Data and Methods 1.1 General data There were 26 patients with cranial defects in this group, 17 male and 9 female. Age 16-56 years old, average 38 years old. The duration of cranial defects was more than 3 months, with an average of 5.6 months. The sites of cranial defects were all frontotemporal top, including 15 cases on the left side and 11 cases on the right side. The minimum area of skull defect was 130 cm2, the maximum area was 192 cm2 (bilateral), and the average area was 162 cm2. The causes of skull defects were as follows: 18 cases after traumatic intracranial hematoma removal and debridement, 7 cases after non-traumatic intracranial hematoma removal and debridement, and 1 case of meningioma and brain hernia with debridement. 1.2 The steps of digital shaping cranioplasty are as follows: 1.2.1 All the patients used the two-dimensional titanium alloy plate which had won the bidding in our hospital, and the hardness and ductility of the plate had been certified by the relevant national certificates. 1.2.2 Inspection methods: CT scanning technology: the United States Medical Systems Hispeed Nx/i double-screw CT scanner was used, applying 3DHead 3mm/HQ scanning, with the conditions of: 150KV,120MA, 1.0s, layer thickness of 3mm, layer spacing of 3mm, pitch of 1.0, matrix of 512×512, window width of 2500, using the Bone window (osteo) 150, scanning with the patient supine on the examination bed, scanning range according to the requirements, post reconstruction layer spacing 1mm, matrix 1024×1024, reconstruction using SSD (surface technology). 1.2.3 The patient is admitted to the hospital that is head CT reconstruction graphic data, the data will be sent to the titanium plate network manufacturers through the Internet, according to the data of the two-dimensional titanium plate processing, production, about 2 days that can be digitally shaped two-dimensional titanium plate cranioplasty material. 1.2.4 Implantation of digitally shaped titanium mesh. 2, the results of all cases of digital shaping cranioplasty after shaping are very satisfactory, postoperative complications include: subcutaneous hematoma in 2 cases (7.6), hematoma absorption after conservative treatment. Subcutaneous effusion was found in 3 cases (11.5), which were cured by puncture aspiration and pressure dressing. There were no other complications. For the follow-up of more than 6 months~1 year after cranioplasty, there was no infection, rejection, exsanguination, displacement or collapse in 26 cases. 3, Discussion Cranioplasty, as a common surgery, is currently recognized as the indications for surgery: (1) cranial defects with a diameter greater than 3M; (2) defects that are aesthetically displeasing: (3) cause long-term dizziness, headache and other symptoms that are difficult to alleviate; (4) meningeal-cerebral scar formation associated with epilepsy (need to be performed at the same time as the epileptic foci of the resection); (5) a serious mental burden affecting the work and life [1]. Cranial defects with a diameter of more than 3 cm can lead to a series of clinical symptoms of craniosynostosis syndrome, affecting aesthetics and increasing the patient’s psychological burden, and in severe cases, serious mental illnesses can occur due to aesthetic disorders, so the purpose of cranioplasty is not only to protect the brain tissue, but to repair the appearance at the same time [2]. Currently, the artificial materials used in cranioplasty are: plexiglass, silicone rubber, hydroxyapatite, titanium mesh [3] and so on. Among them, titanium mesh has good biocompatibility, the protection strength meets the requirements, there is no aging problem, and because the ray can be transmitted, does not contain iron atoms, and can accept CT or MR examination, it is becoming more and more widely used in foreign countries [4]. The titanium mesh used for cranioplasty includes two-dimensional titanium mesh and three-dimensional titanium mesh. Three-dimensional titanium mesh is softer, weaker, and can be shaped intraoperatively (but the shaping effect is poor), which is suitable for small cranial defects, while two-dimensional titanium mesh is stiffer, stronger, and basically can not be shaped intraoperatively, which is suitable for large cranial defects. For cranioplasty of large cranial defects, two-dimensional titanium mesh should be used, and digital contouring can avoid the shortcomings of two-dimensional titanium mesh and make the postoperative craniofacial shape as close to normal as possible, reducing the psychological burden on the patient.In 2008, the department of our 26 cases of large cranial defects in cranioplasty, digital contouring cranioplasty, the temporalis muscle is placed in the outer side of the titanium mesh, cranioplasty surgery, most of the scholars advocate not placing drainage surfaces. Most scholars advocate not placing the drainage tube [1] [5], but the author believes that most scholars advocate not placing the drainage tube is intended to reduce the chance of infection, but due to the injection of water, the separation of traumatic injury, even if the trauma of hemostasis is good, the dura mater or pseudo-dura mater is not divided into breaks, if you don’t place the drainage tube, the dressings in the postoperative period of 1-2 days basically are wet and stained, but also to make subcutaneous easy to accumulate blood and fluid, but increased the chance of infection, now the author advocates that it is best to place a drainage tube, but it is better to place a drainage tube. The author advocates that it is better to place a drainage tube. The cranial shape was beautiful after digital cranioplasty, and the treatment effect was satisfactory. Digital contouring cranioplasty has the following advantages: (1) less trauma, good therapeutic effect, less pain and fewer complications for patients; (2) perfect contouring, better reduction of patients’ mental burden, and better integration into the society; and (3) fewer titanium nails used in the operation. Conventional titanium mesh cranioplasty is safe and effective, digital cranioplasty is based on conventional titanium mesh cranioplasty with digital cranioplasty technology, which can shorten the duration of each operation, shape more accurately without adding any new damage, and is safer, more effective and more perfect for each conventional titanium mesh cranioplasty. For patients with large cranial defects using titanium mesh as a repair material, digital contouring should be used.