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After Le Fort I osteotomy was first performed by von Langernbeck in 1859, there has been many improvements since. Research on and development of Le Fort I osteotomy procedure has shown downward movement of the maxilla to exhibit lowest stability and accuracy. However, maxillary downgraft movement is necessary in orthognathic patients with insufficient vertical length of the maxilla, but fixation of the maxilla after elongation is often very inaccurate. In this study, the authors utilized 3D virtual surgery, CAD/CAM-assisted 3D printing technology to overcome such limitations of maxillary total elongation. In addition, accuracy at 7 different landmarks from superimposition of virtual simulation data and postoperative Cone-beam computed tomography (CBCT) data were measured. Although posterior maxilla exhibited bigger range of errors, an error of <1 mm was measured at all 7 landmarks. Operation time was greatly shortened with cutting guides and customized plates. Although this study is a single-case study, this study shows increased accuracy and efficacy from application of 3D virtual surgery, CAD/CAM, and 3D printing technology.

The zygomatic bone is a structure that protrudes symmetrically on both sides of the midface and plays an important role in the overall aesthetic appearance of the face. Unlike Caucasians, the mesocephalic facial shape is predominant in Asians, and therefore, many people have a relatively laterally developed zygomatic bone. In Asians, when the zygomatic bone is excessively developed, it gives a strong and stubborn image, and aesthetically, many people want to reduce the zygomatic bone because they prefer an oval and slim face. To reduce the excessive zygomatic bone, a reduction malarplasty through an intraoral and preauricular approach has been performed. Although reducing the zygomatic bone is not a big problem in most cases of symmetric reduction malarplasty, it is not easy to produce surgical results as intended by the surgeon in asymmetric malar patients or patients requiring a three-dimensional (3D) change of zygoma. In addition, because of the mobility of the zygoma segment, it may be difficult to drill holes and fix plate after osteotomy. Moreover, these factors can increase the possibility of malunion or nonunion. In this study, cutting guides made with the aid of 3D virtual surgery, 3D printing, and customized titanium plates manufactured with the computer-aided design/computer-aided manufacturing technology are used for 8 patients to maximize the recovery of 3D symmetry and minimize complications through accurate fixation after surgery. During the surgical procedures, screw hole drilling and osteotomy were performed using a cutting guide, and then, the malar segment was fixed by matching the premade customized plates with the predrilled holes. As a result of checking the accuracy of the surgery by superimposing the postoperative 3D cone beam computed tomography image and virtual surgery data based on the skull base, the 2 images almost overlapped and no significant differences were observed, so it was confirmed that the operation was performed exactly as planned. When using the 3D technology, it is possible to perform a more accurate surgery in patients with asymmetry due to congenital anomalies or trauma as well as simple asymmetry, so it can be concluded that using the 3D technology can overcome the limitations and disadvantages of the conventional method as in the cases in this study. The accurate prediction of soft tissue is still insufficient, and further research is needed to overcome this limitation

during cleft palate repair and its effects on eustachian tube function.

cellular subtype. Another classification involves cellular morphology. The 2 patterns of cell morphology are Antoni A and Antoni B. In Antoni A, spindle cells are arranged in "interlacing cords, whorls, or palisades," whereas Antoni B is characterized by "stellate cells, with a mucoid stroma." 1 Treatment of orbital schwannomas is mainly surgical. The surgical approach differs depending on the localization of the tumor 1,4 and may occasionally require an interdisciplinary approach between ophthalmology, otorhinolaryngology, and neurosurgery. Surgical excision is considered a definitive treatment, with recurrence rates being very low. 4,7 In our case, we opted for a superior orbitotomy through a lid-split incision. This approach provided us adequate visualization of the schwannoma, which was in the central, anterior orbit. It also allowed an excellent view of the bony defect of orbital roof in the event a reconstruction was needed. Though rare, potential risks unique to this approach are those involving the eyelid margin, including notching, trichiasis, and irregular contour.We believe the patient's acute presentation of symptomatic diplopia is explained by the intralesional hemorrhage seen on MRI, which may have increased the lesion's size abruptly. It is interesting to note the absence of lid retraction in the patient's postoperative period despite having underwent 2 levator palpebrae resections; we hypothesize that the muscle was mechanically stretched by the tumor throughout the years.We believe our case is unique, given the patient's clinical course as well as the surgical approach through vertical lid-split incision technique. The intraoperative view of the defect in the orbital roof was equally special. We hope this report serves as a reminder to retain diagnostic skepticism in the face of recurrent ptosis and to consider vertical lid-split approach for anterior lesions of the orbit.

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versity) from 2005 to 2020. We reviewed the clinical records and evaluated the patient profile data that consisted of age, sex, clinical symptoms, site of the lesion, surgical approach, rate of recurrence, and survival. In all 4 cases, the diagnosis of MPNST could be confirmed. The most common symptom was rapidly enlarging mass with no nerve palsy associated. One of the patients was a 25-year-old male patient was admitted to the hospital in October 2017 due to "swelling and pain in the left submaxillary region with dysphagia for 2 weeks." The patient was operated in the local hospital in February 2017 due to neurofibroma of the left neck. In August 2017, the patient was operated in the local hospital again due to the tumor in the submaxillary area of the left mouth. The postoperative pathological diagnosis was MPNST, but no further treatment was taken. The male had a family history of neurofibroma. The patient's maxillofacial appearance was found to be asymmetric on admission Address correspondence and reprint requests to Su-