CT Measurement of Diameter and Dimension of the Trachea in Normal Korean Adults (흥부 전산화단층촬영을 이용한 한국성인의 기관내경과 단면적의 측정)
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- Journal of Chest Surgery
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- v.34 no.7
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- pp.534-538
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- 2001
Background: Knowledge of size and morphology of the normal trachea is important for airway management and tracheal reconstruction. Conventional radiography is a simple method used to measure the tracheal diameter, but it is not accurate because of the artifacts related to image magnification and overlapping by the shoulder. The purpose of this study was to provide the normal values of the tracheal size and anatomy in Korean adults using Computerized Topography. Material and Method: There were 43 men and 34 women included in this study. They were divided into three age groups(group 1, 20-39 years ; group 2, 40-59 yeas , groups 3,
Positional accuracy of the on-board imager (OBI) isocenter with gantry rotation was presented in this paper. Three different type of automatic evaluation methods of discrepancies between therapeutic and OBI isocenter using digital image processing techniques as well as a procedure stated in the customer acceptance procedure (CAP) were applied to check OBI isocenter migration trends. Two kinds of kV x-ray image set obtained at OBI source angle of
IAEA's guidance levels have been provided for western people to the end. Guidance levels lower than the IAEA'S will be necessary in view of Korean people's proportions. Therefore, we need to develope the standard doses for Korean people. And we conducted a nationwide survey of patient dose from x-ray examinations in Korea. In this study, the 278 institutions were selected from Members Book of Korean Hospital Association. The valid response rate was approximately 57.9%. Doses were calculated from the questionnaires by NDD method. We obtained the results were as follows; 1) General radiographic equipments were distributed for 42.0%, fluoroscopic equipments 29.4%, dental equipments 13.2%, CT units 8.1 % and mamographic units 7.2%. 2) According to classification by rectification, three-phase equipments were 29.9%, inverter-type generators 29.5%, single-phase equipments 25.5%, constant voltage units 9.0% and unknown units 6.0%. 3) According to classification by receptor system, film-screen types were 46.8%, CR types 26.8%, DR types 17.7% and unknown types 8.9%. 4) The number of examinations were chest 49.2%, spine 16.8% and abdomen 12.7%. 5) Patient doses were head AP 3.44 mGy, abdomen AP 4.25 mGy and chest PA 0.39 mGy.
Purpose: The purpose of this study is that through production of phantom for respiration gated radiotherapy, assessing appropriacy of exposure dose for the therapy using RPM (Real-time Position Management). Materials and Methods: We located measurement object on the phantom for respiration gated radiotherapy made of 2 linear actuator, acrylic panel, stanchion, iron plate ets. to drive (up, down, front, back). Using 4D CT scan, we analyzed patient's respiration and reproduced the movement by computer. On the phantom, we located a 2D-Array (PTW) and an White water phantom (4.5 cm) and used DMLC (interval 2 cm) in the field size
It is well known that Tc-99m HMPAO brain SPECT can reflect the functional lesions better than X-ray computerized tomography(CT) and magnetic resonance imaging(MRI) in the cerebral disorders. In order to evaluate the clinical utilities of Tc-99m HMPAO brain SPECT in patients with post-traumatic chronic organic mental disorder(OMD), we included 28 patients diagnosed as OMD in department of psychiatry after traumatic head injury. And we compared the results of Tc-99m HMPAO SPECT with those of MRI, EEG and MINI mental status ex amination(MMSE). The results were as follows 1) All patients diagnosed as OMD showed diffuse or focal decreased cerebral perfusion on Tc-99m HMPAO SPECT. 2) Most frequent lesion on brain Tc-99m HMPAO SPECT was decreased perfusion on both frontal lobe. And most frequent lesion on brain Tc-99m HMPAO SPECT showing normal brain MRI result was also decreased both frontal perfusion. 3) Eight of 28 patients showed focal brain MRI lesions(4 small frontal hygroma, 3 small cerebral infarction and 1 cerebellar encephalomalacia) which were not detected in brain Tc-99m HMPAO SPECT. 4) The patients showing less than 20 points on MMSE disclosed abnormal results of EEG more frequently than those disclosing more than 20 points. In conclusion, we think that Tc-99m HMPAO brain SPECT is sensitive method to detect functional lesions of the brains in patients with chronic post-traumatic organic mental disorder.
Background : Differentiation of malignity and benignity is crucial for management of solitary pulmonary nodule(SPN). Clinical parameters such as patient's age, nodule size, smoking history, doubling time, typical calcification in X-ray and CT findings have been reported as helpful in this purpose. However, in most cases, these parameters are not conclusive. Glucose metabolism is increased in cancer tissues including lung cancer tissues. After uptake of 2-[F-18]-fluoro-2-deoxy-D-glucose(FDG), the glucose analogue, by cancer cell, FDG is trapped in the cell without further metabolism after phosphorylation. Thus, hypermetabolic focus in FDG-positron emission tomography (PET) imaging suggest malignancy. We evaluated the diagnostic efficacy of FDG-PET imaging in distinguishing malignant and benign SPN. Methods : We evaluated 28 patients with SPN from Jan. 1995 to Jan. 1997. CT scan of chest and whole-body FDG-PET imaging were performed in all patients. Histologic diagnosis was confirmed by transthoracic fine needle aspiration and biopsy, bronchoscopic biopsy and open thoracotomy. Results : Of the 28 SPN's, 22 nodules were malignant and 6 nodules were benign. FDG-PET imaging diagnosed all malignant nodules correctly as positive, and diagnosed 4 of 6 benign nodules correctly as negative. One tuberculous granuloma and one aspergilloma showed hypennetabolic focus and were diagnosed falsely positve with FDG-PET imaging. In the diagnosis of SPN with FDG-PET, sensitivity and specificity were 100% and 66.7%, positive predictive value and negative predictive value were 92% and 100%. Conclusion : FDG-PET imaging is highly useful noninvasive diagnostic tool in distinguishing between malignant SPN and benign SPN.
Background : Pulmonary thromboembolism is relatively frequent and potentially fatal. However, it is commonly misdiagnosed. The incidence of pulmonary thromboembolism is not decreasing despite advances in diagnosis and effective prophylatic measures. Its potential for significant sequela necessitates a prompt diagnosis and treatment. Unfortunately, there are many difficulties and problems regarding accurate diagnosis. There is a low prevalence of deep vein thrombosis and pulmonary thromboembolism in Korea and only few reports on this subject are available. Method : The clinical features of 36 patients, who were diagnosed with pulmonary thromboembolism at the Korea University medical center, were reviewed. Results : 1) There was no significant difference in prevalence between men an women, and the mean age was 50.9 years in men 59.2 years in women. 2) The frequent causes of pulmonary thromboembolism were malignancies (22.2%), surgery (22.2%), and heart disease(8.2%). Specific causes were not identified in 33.3%. 3) The most common symptom was dyspnea(72.2%), and the most common sign was tachypnea(61.1%). 4) The EKG findings were normal in 28.6%, an S1Q3T3 pulmonale pattern in 25.7%, ST or QRS changes in others. 5) The chest X-ray findings indicated pulmonary infiltration in 37.5%, cardiomegaly in 15.6%, pleural effusion in 12.5%, and normal in 27.8%. The perfusion lung scan showed a high probability in 66.7%, and intermediate or low probability in 33.3%. 6) The pulmonary arterial pressure(PAP) in the high probability groups was 57.9mmHg with a higher mortality rate(35%). Conclusion : Pulmonary thromboembolism is not uncommon in Korea and its clinical features do not differ greatly from thase reported in the literature. When pulmonary thromboemblism of unknown causes are diagnosed, a search for an occult malignancy is recommended. Rapid diagnosis and treatment are achieved when thromboemblism is suspected.
Backgrounds/Aims: Pancreatoduodenectomy (PD) is recommended in fit patients with a carcinoma (PDAC) of the pancreatic head, and a delayed resection may affect survival. This study aimed to correlate the time from staging to PD with long-term survival, and study the impact of preoperative investigations (if any) on the timing of surgery. Methods: Data were extracted from the Recurrence After Whipple's (RAW) study, a multicentre retrospective study of PD outcomes. Only PDAC patients who underwent an upfront resection were included. Patients who received neoadjuvant chemo-/radiotherapy were excluded. Group A (PD within 28 days of most recent preoperative computed tomography [CT]) was compared to group B (> 28 days). Results: A total of 595 patents were included. Compared to group A (median CT-PD time: 12.5 days, interquartile range: 6-21), group B (49 days, 39-64.5) had similar one-year survival (73% vs. 75%, p = 0.6), five-year survival (23% vs. 21%, p = 0.6) and median time-to-death (17 vs. 18 months, p = 0.8). Staging laparoscopy (43 vs. 29.5 days, p = 0.009) and preoperative biliary stenting (39 vs. 20 days, p < 0.001) were associated with a delay to PD, but magnetic resonance imaging (32 vs. 32 days, p = 0.5), positron emission tomography (40 vs. 31 days, p > 0.99) and endoscopic ultrasonography (28 vs. 32 days, p > 0.99) were not. Conclusions: Although a treatment delay may give rise to patient anxiety, our findings would suggest this does not correlate with worse survival. A delay may be necessary to obtain further information and minimize the number of PD patients diagnosed with early disease recurrence.
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70