• Progress in Medical Physics
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• v.13 no.4
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• pp.218-223
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• 2002

Stereotactic radiosurgery for intracranial lesion is well established since the Lars Leksell first introduced radiosurgery concept in 1951 Its use in the treatment of spinal lesion has been limited by the availability of effective immobilization devices. The first clinical experience of the spinal stereotactic radiosurgery technique was reported by Hamilton AJ. in 1995. Recently, Optic-guided patient positioning technique for extracranial stereotactic radiosurgery was developed and reported. This study is for assess the target positioning accuracy of the optic guided patient positioning system Exactrac (BrainLab., Inc, Germany). We have designed phantom for assess the accuracy of spinal stereotactic radiosurgery The infrared reflective body markers attached to the relatively immobile part of the body and a series of 2 mm CT images was taken. The image sets were transferred to the planning computer. During the radiosurgery treatment, we measure the real-time display showing the positioning values from Exactrac computer. And we compare the isocenter deviation from irradiated center point of the film which was mounted on the lesion site of the phantom and pin hole site of that film. The accuracy of the ExacTrac system in positioning a target point shows enough for the clinical applications.

• Progress in Medical Physics
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• v.24 no.4
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• pp.290-294
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• 2013

Stereotactic Radiosurgery require high accuracy and precision of patient positioning and target localization. We evaluate the real time positioning accuracy of isocenter using optic guided patient positioning system, ExacTrac (BrainLab, Germany), during spinal radiosurgery procedure. The system is based on real time detect multiple body markers attached on the selected patient skin landmarks. And a custom designed patient positioning verification tool (PPVT) was used to check the patient alignment and correct the patient repositioning before radiosurgery. In this study, We investigate the selected 8 metastatic spinal tumor cases. All type of tumors commonly closed to thoracic spinal code. To evaluate the isocenter positioning, real time patient alignment and positioning monitoring was carried out for comparing the current 3-dimensional position of markers with those of an initial reference positions. For a selected patient case, we have check the isocenter positioning per every 20 millisecond for 45 seconds during spinal radiosurgery. In this study, real time average isocenter positioning translation were $0.07{\pm}0.17$ mm, $0.11{\pm}0.18$ mm, $0.13{\pm}0.26$ mm, and $0.20{\pm}0.37$ mm in the x (lateral), y (longitudinal), z (vertical) directions and mean spatial error, respectively. And body rotations were $0.14{\pm}0.07^{\circ}$, $0.11{\pm}0.07^{\circ}$, $0.03{\pm}0.04^{\circ}$ in longitudinal, lateral, table directions and mean body rotation $0.20{\pm}0.11^{\circ}$, respectively. In this study, the maximum mean deviation of real time isocenter positioning translation during spinal radiosurgery was acceptable accuracy clinically.

• Radiation Oncology Journal
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• v.18 no.4
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• pp.309-313
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• 2000

The metastasis of uterine leiornyosarcorna to the neck node has not been reported previously and the radiotherapy has been rarely used for the metastatic lesion of the other sites. We report a case of neck metastasis from a uterine leiornyosarcorna, which developed 10 months after surgery and postoperative pelvic radiotherapy. It also involved the parapharyngeal space, adjacent spine, and spinal canal. The metastatic neck mass was inoperable, and was treated by neck radiotherapy (6,000 cGy) and chemotherapy including taxol and carboplatin. The mass has regressed progressively to a nearly impalpable state. She has never developed spinal cord compression syndrome, and has maintained good swallowing for eight months since the neck radiotherapy and chemotherapy. Since the extensive metastatic neck mass showed good local response to high dose radiotherapy and chemotherapy, both treatments may be considered for an unresectable metastatic leiornyosarcorna.

• Journal of the Korean Orthopaedic Association
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• v.56 no.5
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• pp.419-426
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• 2021

Purpose: In the surgical treatment of pyogenic lumbar spondylodiscitis, screw insertion at the affected vertebra has been avoided because of biofilm formation, and the risk of infection recurrence. The authors analyzed the success rate of infection treatment while minimizing the number of instrumented segments by inserting pedicle screws into the affected vertebrae. Therefore, this study examined the usefulness of this technique. Materials and Methods: From January 2000 to June 2018, among patients with pyogenic lumbar spondylodiscitis treated surgically, group A consisted of patients with pedicle screws inserted directly at the affected vertebrae (28 cases), and group B underwent fusion by inserting screws at the adjacent normal vertebrae due to bone destruction of the affected vertebral pedicle (20 cases). The classified clinical results were analyzed retrospectively. All patients were treated via the posterior-only approach, so the affected disc and sequestrum were removed. Posterior interbody fusion was performed with an autogenous strut bone graft, and the segments were then stabilized with pedicle screw systems. The hospitalization period, operation time, amount of blood loss, EQ-5D index, duration of intravenous antibiotics, and the clinical and radiological results were analyzed. Results: In group A, the number of instrumented segments, operation time, blood loss, and EQ-5D index at one month postoperatively showed significant improvement compared to group B. There were no significant differences in the duration of antibiotic use, hospitalization, radiological bone union time, sagittal angle correction rate, and recurrence rate. Conclusion: Minimal segmental fixation, in which pedicle screws were inserted directly into the affected vertebrae through the posterior approach, reduced the surgery time and blood loss, preserved the lumbar motion by minimizing fixed segments and showed rapid recovery without spreading or recurrence of infection. Therefore, this procedure recommended for the surgical treatment of lumbar pyogenic spondyodiscitis.

• Journal of radiological science and technology
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• v.46 no.6
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• pp.527-533
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• 2023

The purpose of this study is to evaluate the clinical risk of spinal radiosurgery by calculating the dose difference due to dose calculation algorithm and multi-leaf collimator positioning error. The images acquired by the CT simulator were recalculated by correcting the multi-leaf collimator position in the dose verification program created using MATLAB and applying stoichiometric calibration and Monte Carlo algorithm. With multi-leaf collimator positioning error, the clinical target volume (CTV) showed a dose difference of up to 13% in the dose delivered to the 95% volume, while the gross tumor volume (GTV) showed a dose difference of 9%. The average dose delivered to the total volume showed dose variation from -8.9% to 9% and -10.1% to 10.2% for GTV and CTV, respectively. The maximum dose delivered to the total volume of the spinal cord showed a dose difference from -14.2% to 19.6%, and the dose delivered to the 0.35 ㎤ volume showed a dose difference from -15.5% to 19.4%. In future research, automating the linkage between treatment planning systems and dose verification programs would be useful for spinal radiosurgery.

• Journal of radiological science and technology
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• v.34 no.4
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• pp.263-269
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• 2011

Since the spine radiography were explained differently at every several hospitals and textbooks. the technique has not been accurately defined and interfered each other. We would like to define the most appropriate positioning for clinical cases, and reference books, by comparing scoliotic angle and lordotic angle. From Mar 2009 to Sep 2011, 85 patient cases were studied, who had not been undergone surgical treatment among spondylopathy patients. Scoliotic angle and lordotic angle were measured, using Cobb's method. We analyzed statistically using t-test(SPSS 18), and evaluated spine general radiography position. Moreover, we researched on the actual condition at 10 university hospitals in Seoul. The results of scoliotic angle measurement, the value at erect position showed 20.98% higher than supine position, and it has statistical significance (p<.01). In lordotic angle measurement, the value at neutral holding position represented 29.3% higher than supine position, and it also has statistical significance(p<.01). The results of clinical survey, supine posine(70.0%) took much higher possession than erect position(30.0%). In conclusion, compare to supine position, erect position shows increased scoliotic and lordotic angle. It was agreed with the importance of clinical erect position radiography, which gravity affects. So clinical radiologist must recognize the difference, and conduct an accurate study.

• The Journal of the Korean bone and joint tumor society
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• v.6 no.1
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• pp.1-9
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• 2000

Purpose : Spine is one of the most common sites of the metastatic bone tumors. Conservative management such as chemotherapy or radiotherapy has been preferred in most cases. However, the neurologic deficit has not been usually improved, and the quality of life was poor. The purpose of this study was to show the efficacy of the surgical treatments for metastatic spinal tumors in terms of postoperative improvements of neurologic deficit and survival time. Materials and Methods : Authors have reviewed the literatures and analyzed 14 patients of metastatic spinal tumors who were received operative treatments between August 1991 and June 1999 at the our department of orthopaedic surgery. Results : The most frequent primary tumor was breast cancer in women and lung cancer in men. The thoracic region was the most common site. There was a preponderance of females over males, and the age ranged between 4th and 8th decade. The indications of surgical treatment comprised instability, progressive neurologic findings, resistance to radiotherapy, pathological fracture, long life expectancy( >6weeks), isolated metastasis and need for pathological diagnosis. The degree of preoperative neurological deficit might influence on the improvement of clinical symptoms after surgery. Conclusion : The surgical treatment reduced the neurological deficit and pain regardless of the operative methods. In the early stage of neurological deficit, the surgical treatment was important for better prognosis. Recently early active operative treatment was performed for metastatic spinal tumor to minimize the intractable pain and to prevent the progression of the neurologic deficit. Early intervention can improve the quality of life and long term survival.

• Journal of the Korean Society of Radiology
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• v.17 no.7
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• pp.1123-1131
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• 2023

This study aimed to present a method to effectively suppress metal artifacts caused by spinal fusion surgery during spinal MRI study. For this purpose, a phantom made of spinal surgery screws was created to reproduce the metal artifact. Then, images were acquired with 1.5T and 3.0T MRI to evaluate changes in metal artifacts according to magnetic field strength. In addition, metal artifacts were evaluated by increasing the receive bandwidth to 200, 400 and 800 Hz/PX. As a result, metal artifacts occurring in images obtained from the 1.5T MRI decreased by approximately 52.2% compared to images obtained from the 3.0T MRI, showing a significant difference (p<0.05). In particular, the signal loss and signal pile up areas were reduced by approximately 52.81% and 42.71%, respectively, showing a significant effect in suppressing metal artifacts. On the other hand, when images were acquired while increasing the receive bandwidth from 200 to 800 Hz/PX, there was no significant effect, with a decrease of up to 8.93% for the 1.5T MRI and up to 10.98% for the 3.0T MRI (p>0.05). As a result of this study, increasing the receive bandwidth reduced signal loss and reduced some metal artifacts, but did not have a significant effect because it did not suppress signal pile up. However, when the magnetic field strength was reduced from 3.0T to 1.5T, signal loss and signal pile up were greatly reduced, effectively improving the metal artifact. Therefore, in order to suppress metal artifacts caused by spinal fusion surgery, study using a low magnetic field MRI can be said to be the most effective method.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.2
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• pp.171-175
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• 2006

The involvement in the spine of eosinophilic granuloma is not common. Especially, involvement of cervical spine and posterior neural arch is quite rare. In addition, radiographic findings including magnetic resonance images of eosinophilic granuloma are manifested as vertebral body collapse, loss of pedicle and paravertebral soft mass formation; it must be differentiated with other conditions, such as malignant bone tumor, metastatic cancer or tuberculous spondylitis. We experienced three cases of eosinophilic granuloma involving posterior neural arch of C4, C7, and body of C4 respectively, which were performed surgical treatment and achieved complete healing. We report these cases with review of literatures.

• The Journal of the Korean bone and joint tumor society
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• v.13 no.1
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• pp.37-42
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• 2007

Purpose: Because of the anatomical characteristics, it is difficult to perform radical operation in spinal tumor. Numerous operations on primary and metastatic spinal tumor have been performed and among those total en bloc spondylectomy has produced decent clinical result. Clinical and radiological results have been analyzed based on five total en bloc spondylectomy on primary and metastatic spinal tumor. Materials and Methods: Patients included in this study were one with primary and four with metastatic spinal tumors, from June 1997 to January 2006. Two of the four were originated form kidney. One was from breast and the other one was not identified. McAfee's 4 point scale, VAS and Frankel's classification have been used as clinical assessment of pain and neurological symptoms. Clinical assessment have been conducted for every 3 months after operation including local recurrence, bone union and complications. Results: Assessment of pain decreased from average of 3 before operation to 1.6 after operation in McAfee's scale and VAS decreased from average of 9.2 to 1.6. Neurological deficit after operation improved from C to D in Frankel's category. Local recurrence has been detected on metastatic adenocarcinoma of L4 during follow up. Conclusion: Total en bloc spondylectomy is evidently useful operational method for primary and metastatic spinal tumor since it completely decompresses spinal nerves, decreases axial pain immediately and improves the quality of remaining life.