INTRODUCTION: The fixation strength of transpedicular screw system in the vertebral hody relied on bone quality and anatomical characteristics of vertebral pedicle, designs of screw and types of connection(rod or plate) with screw. The purpose of this study is to verify the biomechanical nature of the transpedicular fixation in spine under various conditions with porcine vertebrae. MATERIAL AND METHOD: Fresh porcine vertebrae and the custom-made screws were used in this experiment. To reduce the errors caused by vertebral bodies of different size and quality, vertebral bodies having regular range of pedicular width(10.0 to 11.5mm) and hone density(more than 1.0 gm/cm2) were used. The pedicle screws were inserted in the same procedure and axial pull out test was performed with using the Material Testing System(lntron8511, Canton, USA). The experiments were performed in four types to assess the difference of strength accroding to designs of the screw hy using two group of screws. The first group of screw was designed according to the outer and inner diameter and the second group was designed according to the shape, pitch, and thread profile of screw. Experiment I was perfomed to evaluate the effect of screw diameters on the biomechanical pull-out strength hy using the first group of custom-made pedicle screw which fixed all other factors except the diameter of screw. Experiment I was to verify the effect of screw shape, experiment III to verify the effect of pitch and experiment IV to verify the effect of thread profile. RESULTS: The results of experiments were summarized as follows: Experiment I showed that the screw of larger outer diameter had greater holding strength. Experiment II showed that the holding strength of cylindrical shaped screw is superior to that of conical shaped screw. Experiment III showed that there is no statistical significance between different modes of pitch. Experiment IV showed that the holding strength of buttress shape of thread profile is superior to that of V-shape. CONCLUSION: It seemed that the fixation strength of the screw was more powerful with 1 mm increment of outer diameter in 4-7mm of outer diameter, 3mm of pitch and buttress shape of thread of the screw with the same operation technique.
Spine

OBJECTIVE: This study is to investigate whether Positron Emission Tomography (PET) is useful for determining pathologic complete response in patients with ovarian carcinoma who had a clinical complete response after primary treatment. METHODS: FDG-PET scans were performed in 10 patients with advanced ovarian cancer (4 patients with stage IIC, 6 patients with IIIC), who showed complete response with cytoreductive surgery and 6 cycles of post-operative adjuvant Cisplatin-based combination chemotherapy. FDG-PET scan was obtained with GE Advance Scanner, beginning at 50 minutes after injection of 370-555 MBq (10-15 mCi) of 18F FDG. Uptakes exceeding 3.5 SUV (Standardized Uptake Value) or larger than surrounding tissue were determined as a positive findings. Second-look laparotomy was undertaken within median 4 days after FDG-PET scanning. RESULTS: The mean age of the patients was 45 years and serous cystadenocarcinoma was most common histologic type. None showed active lesion in pelvis or abdomen with FDG-PET scan (SUV: >3.5 kg/ml), however, 5 patients (50%) showed residual tumors on multiple biopsy during second look operation. One patient showed positive lesion in lung on FDG-PET scan, which was confirmed to have metastatic lesion. CONCLUSION: FDG-PET scan is not useful for detection of small ovarian cancer lesions in pelvis and abdomen and cannot substitute for second-look operation to determine pathologic complete response.
Abdomen ; Biopsy ; Cystadenocarcinoma, Serous ; Drug Therapy, Combination ; Humans ; Laparotomy ; Lung ; Neoplasm, Residual ; Ovarian Neoplasms* ; Pelvis ; Positron-Emission Tomography

The authors analyzed 11 cases of pineal region tumor in young male patients who had been treated at the Capital Armed General Hospital. So, the following results were obtained. 1) Due to the army distinctiveness, all cases were young male patients. 2) An unusual large proportion of pineal region tumor(26.2%) was noted. 3) Headache and vomiting were main presenting symptoms and the duration of symptoms was short. 4) The tumors were mainly presented as a round well-enchancing masses with calcification. Also, nearly all were associated with hydrocephalus. 5) MRI was very useful for the demonstration of tumor extent. 6) Based on the classification of pineal tumor, the tumors of germ cell origin were predominant(81.9%). 7) The extrapineal metastasis was frequent. 8) The tumor marker(alpha-FP and HCG) was postive in 4 cases(36.4%). 9) Germinoma showed excellent prognosis for the irradiation following a drainage procedure.
Arm ; Classification ; Drainage ; Germ Cells ; Germinoma ; Headache ; Hospitals, General ; Humans ; Hydrocephalus ; Magnetic Resonance Imaging ; Male ; Neoplasm Metastasis ; Pinealoma ; Prognosis ; Radiotherapy ; Vomiting