• 대한치과의사협회지
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• 제52권3호
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• pp.132-138
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• 2014

The emergence of Cone Beam Computed Tomography(CBCT) in the late 1990s represented an innovative advancement in the field of dental and maxillofacial radiology because it greatly reduced the radiation exposure to patients and offered 3D images easily. The 3D information generated by this technique brings the potential of improved diagnosis and treatment planning for a wide range of clinical applications in dentistry. The use of CBCT includes diagnosis and surgical assessment of the orofacial hard tissue lesions, dental implant treatment planning and postoperative evaluation, TMJ assessment, diagnosis of craniofacial fracture, orthodontics, endodontics, and so on. All CBCT examinations should be justified on an individualized needs. The clinical benefits to the patient for each CBCT scan must outweigh the potential risks associated with exposure to ionizing radiation. CBCT scans should be taken with initially obtained medical and dental histories of patients and a close clinical examination. CBCT should be considered as an imaging alternative of other conventional radiography in cases where the anatomical structures of interest may not be seen. The smallest possible field of view(FOV) and the lowest setting of tube current and scan time should be chosen, and the entire images scanned should be interpreted by a qualified expert.

• Imaging Science in Dentistry
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• 제44권2호
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• pp.129-135
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• 2014

Purpose: The objective of this study was to assess the trabecular bone changes that occurred around functional endosseous dental implants by means of radiographic image analysis techniques. Materials and Methods: Immediate preoperative and postoperative periapical radiographs of de-identified implant patients at the University Dental Hospital of Manchester were retrieved, screened for specific inclusion criteria, digitized, and quantified for structural elements of the trabecular bone around the endosseous implants, by using image analysis techniques. Data were analyzed using SPSS version 11.5. P values of less than 0.05 were considered statistically significant. Results: A total of 12 implants from 11 patients were selected for the study, and 26 regions of interest were obtained. There was a significant increase in the bone area in terms of the mean distance between nodes (p=0.006) and a significant decrease in the marrow area in terms of the bone area (p=0.006) and the length of marrow spaces (p=0.032). Conclusion: It appeared that the bone around the implant underwent remodeling that resulted in a net increase in bone after implant placement.

• International journal of advanced smart convergence
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• 제9권1호
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• pp.37-46
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• 2020

Cerebral vascular surgery can damage patients' motor and sensory nerves; therefore, neuromonitoring is performed intraoperatively. Patients with diabetes often have peripheral neuropathy and may be prone to nerve damage during surgery. This study aimed to identify factors that should be considered when diabetic patients undergo intraoperative neuromonitoring during brain vascular surgery and to present new criteria. Methods: In patients with and without diabetes who underwent cerebrovascular surgery (n = 30/group), we compared the intraoperative stimulation intensity, postoperative motor power and sensory, glycated hemoglobin (HbA1c) and glucose levels, and imaging findings. Results: Fasting glucose, blood glucose, and HbA1c levels were 10%, 12.1%, and 9.7%, respectively; they were higher in patients with than in patients without diabetes. Two patients with diabetes had weakness, and 10 required increased Somato sensory evoked potential (SSEP) stimulation, while in 16, motor power recovered over time rather than immediately. The non-diabetic group had no weakness after surgery, but 10 patients required more increased SSEP stimulation. The diabetic group showed significantly more abnormal test results than the non-diabetic group. Conclusion: For patients with diabetes undergoing surgery with intraoperative neuromonitoring, whether diabetic peripheral neuropathy is present, their blood glucose level and the anesthetic used should be considered.

• Journal of Korean Neurosurgical Society
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• 제30권10호
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• pp.1220-1223
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• 2001

Authors experienced a unique case of craniopharyngioma which had evolved rapidly after 4 years of total resection for supratentorial meningioma. A 58-year-old woman presented with headache and visual deterioration. Previously, she had undertaken surgical removal of frontal convexity meningioma 4 years ago and had been well without any postoperative sequelae thereafter. Brain magnetic resonance imaging demonstrated a newly developed suprasellar mass. Pertinent operative procedure was performed and histological verification was made as an adamantinomatous craniopharyngioma. She has been showing unremarkable clinical course up to date. Possible pathogenic mechanisms of de novo development of craniopharyngioma are disscussed with review of case.

• Journal of Korean Neurosurgical Society
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• 제46권2호
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• pp.161-164
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• 2009

Plasma cell granuloma is a tumor-like disease characterized by non-neoplastic polyclonal proliferation of plasma cells and other mononuclear cells. This disease occurs most frequently in the lung and upper respiratory tract, while the involvement of the central nervous system is very rare. A 44-year-old female patient presented with nausea and progressive visual disturbance. Brain magnetic resonance imaging (MRI) revealed the mass along the right tentorium with low signal intensity in the T2 weighted image (T2WI) and fluid-attenuated inversion recovery (FLAIR) sequence, and an isosignal intensity in T1 weighted image (T1WI), the latter of which was enhanced after administration of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA). The thickest portion of the tentorium was partially excised via the combined suboccipital and infratentorial approach. The histopathological examination indicated a diagnosis of plasma cell granuloma. Postoperative steroid therapy was administered for remnant tumor control. Although a follow up MRI scan taken 20 months after the operation showed a slight decrease in tumor size, the lesion had extended to the falx and left frontal convexity along with parenchymal edema at 32 months after the operation and the clinical status was aggravated. The mass was removed from the left frontal convexity. Radiation therapy was given, together with steroid administration.

• Journal of Korean Neurosurgical Society
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• 제54권4호
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• pp.350-354
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• 2013

To present a rare case of a cystic giant schwannoma of the sacrum mimicking aneurysmal bone cyst (ABC). A 54-year-old man visited our institute complaining left leg weakness and sensory change for several years. Magnetic resonance imaging revealed a large multilocular cystic mass with canal invasion and bone erosion confined to left S1 body. The lesion showed multiple septal enhancement without definite solid component. Initially the tumor was considered as ABC. The patient underwent grossly-total tumor resection with lumbosacral reconstruction via posterior approach. The tumor was proved to be a cystic schwannoma. The postoperative course was uneventful and the patient was relieved from preoperative symptoms. We present a rare case of pure cystic giant schwannoma confined to sacrum mimicking ABC. The surgical treatment is challenging due to the complex anatomy of the sacrum. Schwannoma should be considered in the differential diagnosis of osteolytic sacral cysts.

• Journal of Korean Neurosurgical Society
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• 제50권5호
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• pp.468-471
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• 2011

Mesenchymal chondrosarcomas are rare malignant tumors of the bone and soft tissue. Spinal mesenchymal chondrosarcomas are even rarer and, to the best of our knowledge those that are concomitantly located in the intradural and extradural regions, have never been reported. We report a case of a 25-year-old man with back pain and bilateral progressive weakness of the lower extremities. Magnetic resonance imaging revealed a markedly enhanced dumbbell-shaped mass at the T7 level. The lesion was intradurally located at the left side of the spinal cord, and extended extradurally to the extraforminal space through the T7-8 intervertebral foramen. The tumor was completely excised through a posterior approach. Microscopic examination and immunohistochemical studies confirmed mesenchymal chondrosarcoma. Postoperative radiation therapy and chemotherapy were also performed to prevent local recurrence and metastasis. The patient has been symptom-free for two years after surgery. Herein, we reviewed and discussed the clinical characteristics, treatments, and outcomes of primary intraspinal mesenchymal chondrosarcomas in the literature.

• Journal of Korean Neurosurgical Society
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• 제56권1호
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• pp.16-20
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• 2014

Objective : Two-dimensional fluoroscopy-based computerized navigation for the placement of pedicle screws offers the advantage of using stored patient-specific imaging data in providing real-time guidance during screw placement. The study aimed to describe the accuracy and reliability of a fluoroscopy-based navigation system for pedicle screw insertion. Methods : A total of 477 pedicle screws were inserted in the lower back of 96 consecutive patients between October 2007 and June 2012 using fluoroscopy-based computer-assisted surgery. The accuracy of screw placement was evaluated using a sophisticated computed tomography protocol. Results : Of the 477 pedicle screws, 461 (96.7%) were judged to be inserted correctly. Frank screw misplacement [16 screws (3.3%)] was observed in 15 patients. Of these, 8 were classified as minimally misplaced (${\leq}2mm$); 3, as moderately misplaced (2.1-4 mm); and 5, as severely misplaced (>4 mm). No complications, including nerve root injury, cerebrospinal fluid leakage, or internal organ injury, were observed in any of the patients. Conclusion : The accuracy of pedicle screw placement using a fluoroscopy-based computer navigation system was observed to be superior to that obtained with conventional techniques.

• 대한두경부종양학회지
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• 제19권2호
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• pp.179-183
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• 2003

Osteosarcoma is one of the most frequently occurring malignant bone tumor except for multiple myeloma. However, osteosarcoma of the mandible is rare and aggressive malignancy constituting about 5% to 13% of all cases of skeletal osteosarcoma. The authors experienced a case of osteosarcoma of the mandible in a 31-years old male patient. He visited our outpatient clinic with painless mass of the cheek. On the basis of the clinical and imaging findings, the differential diagnosis included giant cell tumor, histiocytosis and malignant bone tumor. In the first operation, the mass of the mandible was excised. Intraoperative microscopic examination of a frozen section did not yield a diagnosis: however, the final definitive histologic examination revealed osteoblastic osteosarcoma. After 15days, wide excision with hemimandibulectomy was completed followed by postoperative radiotherapy and chemotherapy. With our experience, we report the progression of diagnosis and management for mandibular osteosrcoma.

• Clinics in Shoulder and Elbow
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• 제19권2호
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• pp.84-89
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• 2016

Background: The purpose of this study was to assess the results of arthroscopic bridging repair using a human dermis allograft in the treatment of massive irreparable rotator cuff tears. Methods: From November 2009 to April 2011, 12 patients underwent arthroscopic bridging repair using a human dermis allograft in the treatment of massive irreparable rotator cuff tears. Patients were followed for an average of 33.9 months. Clinical outcome was evaluated preoperatively and postoperatively using the mean University of California, Los Angeles (UCLA) score and the Korean Shoulder Scoring System (KSS). Magnetic resonance imaging (MRI) was performed postoperatively at an average of 6.5 months. Results: At a mean follow-up of 33.9 months (range, 25 to 42 months), 11 out of 12 patients were satisfied with their procedure. Patients showed significant improvement in their mean modified UCLA score from 15.9 preoperatively to 29.4 postoperatively (p=0.001). The mean KSS score improved from 45.6 preoperatively to 80.5 postoperatively (p=0.002). In MRI studies, 9 out of 12 patients had full incorporation of the graft into the native rotator cuff remnant. To date, there has been no intraoperative or postoperative complication from the graft procedure, such as infection or allograft rejection, in any patient. Conclusions: Arthroscopic bridging repair using a human dermis allograft can be considered as an option in treatment of select cases of massive irreparable rotator cuff tears, resulting in high patient satisfaction.