• The Korean Journal of Nuclear Medicine Technology
• /
• v.20 no.2
• /
• pp.46-48
• /
• 2016

Purpose The liver one of the most common site for distant metastasis for a variety of tumor, especially of gastrointestinal origin. the purpose of this study was to analyze image quality between standard scan and additional liver scan. Materials and Methods From September 2015 to February 2016. 152 patients were examined undergo gastrointestinal cancer. 32 patients confirmed liver metastasis analyzed same liver ROI level and check the SNR, SUV and T/N ratio Results The $SNR_{mean}$ of standard was $17.7{\pm}10.3$; addition was $22.3{\pm}9.7$ (p<0.05). In $SUV_{max}$ of standard was $6.7{\pm}2.8$; addition was $7.6{\pm}3.2$ (P<0.05). and the T/N ratio of standard was $2.1{\pm}0.6$; addition was $2.5{\pm}0.8$ (P<0.05). Conclusion The $SNR_{mean}$, $SUV_{max}$ and T/N ratio were higher than those on the first scan (P<0.05). The SNRmean showed the highest change rate among the parameters. A additional liver scan is more favorable for the detection of gastrointestinal cancer patients.

• The Korean Journal of Nuclear Medicine
• /
• v.26 no.2
• /
• pp.312-317
• /
• 1992

To evaluate the sensitivity and specificity of captopril renal scan for renovascular hypertension, we employed the captopril renal scan in conjunction with renal angiography in 81 patients, 159 kidneys, who were referred to evaluate the cause of hypertension. We defined the renovascular hypertension by the criteria of demonstration of renal artery stenosis by angiography, and improvement or cure of hypertension by revascularization. Visual and quantitative evaluation of $^{99m}Tc-DTPA$ renal scan was peformed pre and post captopril administration. The prevalence rate of renovascular hypertension was 40% in comparing with renal angiography, and 70% in confirmed cases. The causes of renovascular hypertension in 81 patients were Takayasu's arteritis, fibromuscular dysplasia, atherosclerosis, essential hypertension, chronic pyetonephritis etc. The sensitivity and specificity of captopril renal scan in comparing with renal angiography were 80%, 86.5%, respectively and also 84.2%, 72.6% in confirmed cases of renovascular hypertension, respectively. The causes of false negative cases were nonfunctioning kidney due to complete obstruction or long duration of disease in basal scan, segmental branch artery stenosis, unknown causes, and suspicious true negative cases without confirmation. The false positive cases were abdominal aortic stenosis or aneurysm, dehydration, unknown causes, and suspicious true positive cases. We conclude that captopril renal scintigraphy is highly sensitive, reasonably specific diagnostic method and comparable to other techniques very favorably.

• Clinical and Experimental Pediatrics
• /
• v.53 no.3
• /
• pp.408-413
• /
• 2010

Purpose : We aimed to prove the relative limitation of $^{99m}Tc-DMSA$ scintigraphy (DMSA) compared to computed tomography (CT) in diagnosing acute pyelonephritis (APN) in children. Methods : Since September 2006, after a 64-channel CT was imported, 10 DMSA false-negative patients have been identified: these patients underwent a CT scan for acute abdomen or acute febrile symptoms and were diagnosed as having APN; however, their DMSA scans were clear. We focused on these 10 DMSA false-negative patients and analyzed their clinical findings and CT results. We used Philips Brilliance Power 64-channel CT scanner for the CT scan and Siemens Orbitor Nuclear Camera 60 Hz for the DMSA scan. Results : The 10 DMSA false-negative patients were mostly males (80%) and infants (80%). They had fever for a mean of 1.1-day duration before admission and showed increase in acute reactants: leukocyte, erythrocyte sedimentation rate, and C-reactive protein. The CT findings of renal lesions were focal in 6 (60%) cases and diffuse in 4 (40%) cases, and most of the lesions were unilateral in 80% of patients. CT proved that 22 renal lesions were neglected by DMSA. Differential renal function test by DMSA was also of no use in the evaluation of renal lesions. Conclusion : In this study, DMSA scan showed limitation in finding renal cortical lesions of CT-proven APN patients. DMSA false-negative results seem to occur at early-phase disease of infantile age, but more prospective studies are needed to determine the reasons and their prevalence.

• Journal of the Korean Ceramic Society
• /
• v.41 no.5
• /
• pp.364-369
• /
• 2004

The barrier and optical properties of AlO$_{x}$ thin films on polycarbonate deposited by Reactive Ion Beam Sputtering (RIBS) were investigated at different oxygen partial pressure. We measured the deposition rate of AlO$_{x}$ thin films. As the oxygen partial pres-sure increased, the deposition rate increased then decreased. The changes of deposition rate are associated with the properties of deposited films. The properties of deposited AlO$_{x}$ thin films were studied using X-ray Photoelectron Spectroscopy (XPS), Scan-ning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM). Optimum deposition parameters were found for fabricat-ing aluminum oxide thin films with high optical transparency for visible light and low Oxygen Transmission Rate (OTR). The optical transmittance of AlO$_{x}$ thin film deposited on polycarbonate (PC) showed the same value of bare PC.bare PC.

• Journal of Biomedical Engineering Research
• /
• v.10 no.3
• /
• pp.309-316
• /
• 1989

In this paper, the patient monitor consisting of amplifier, scan converter, A/D converter, CRT amplifier, and micro-controller part was developed. This patient monitor measures the patient's 4 states in the hospital such as electro-cardiography, respiration, blood pressure, and temperature. The control and processing methods based on micro-processor employ the flexibility, extensibility and economy over other conventional system. The followings are incorporated in this system. First, record the heart rate trends for 1 and 4 hours respectively. Second, measures the respiration by impedance pneumography. Third, measures the blood pressure with auto-zero balance. Fourth, linesrize the temperatures by bridge method.

• Proceedings of the IEEK Conference
• /
• 2002.06e
• /
• pp.75-78
• /
• 2002

Since power failures in high-speed communication network, especially in HFC(Hybrid Fiber Coaxial cable) network are critical, microcontroller-based UPS(Uninterrupted Power Supply) are commonly used in the network. Hardware and software of UPS management system is designed and implemented to monitor and control UPS status to supply electric power to ONU and TBA in the HFC network. The result of laboratory tests and field tess of this system shows the scan rate to be 1 to 10 minutes to sufficiently monitor the status of UPS in the network.

• 대한핵의학회:학술대회논문집
• /
• 1967.11a
• /
• pp.104.3-104.3
• /
• 1967

• The Korean Journal of Nuclear Medicine
• /
• v.35 no.3
• /
• pp.117-124
• /
• 2001

Serum thyroglobulin measurement and I-131 whole-body scintigraphy (WBS) are well-established methods for the detection of recurrence in the follow-up of patients with thyroid carcinoma. However, inconsistent results are observed frequently, and these two methods are not always able to detect recurrence. In some patients, serum thyroglobulin level is elevated but the WBS is negative, because the recurrent tumor is too small and below the sensitivity of the diagnostic scan, or there is a dissociation between thyroglobulin synthesis and the iodine frapping mechanism. In such cases, various nuclear imaging methods including Tl-201 Tc-99m-sestamibi, and F-18-FDG PET can be used besides anatomical imaging methods. Among them, FDG PET localizes recurrent lesions in WBS-negative thyroid carcinoma with high accuracy. Several studies have suggested that empirical high-dose I-131 therapy resulted in a high rate of visualization in post-therapy scans with evidence of subsequent improvement. An important question is when to operate on patients with recurrent tumor. We believe that surgical removal is the best means of treatment for patients with localized persistent tumor, despite the high-dose I-131 therapy. with tumor in thyroid remnant, and with isolated recurrence in the lymph node, lung or bone. In addition, we recommend palliative resection of locally unresectable mass with subsequent treatment with high-dose I-131 therapy. Before I-131 therapy, the evaluation of sodium-iodide symporter expression in thyroid carcinoma can predict iodine uptake. Retinoic acid is known to induce redifferentiation, and to enhance I-131 uptake in thyroid carcinoma. Retinoic acid therapy may represent an alternative approach before high-dose I-131 therapy.

• Journal of Trauma and Injury
• /
• v.23 no.2
• /
• pp.142-150
• /
• 2010

Purpose: In this study, patients in whom two computed tomography (CT) scans had been obtained within 24 hours of injury were analyzed to determine the incidence, risk factors and clinical significance of a progressive intracerebral hematoma (PIH). Methods: Participants were 182 patients with a traumatic intracerebral hematoma and contusion who underwent a repeat CT scan within 24 hours of injury. Univarite and multivariate statistics were used to define growth (volume increase) and to examine the relationship between the risk factors and hemorrhage expansion. Results: Fifty-four percent of the patients experienced progression in the size of the lesion in the initial 24 hours postinjury. A PIH was independently associated with worsened Glasgow coma scale (GCS) score (2.99, 1.04~8.60), the presence of subarachnoid hemorrhage (6.29, 2.48~16.00), the presence of a subdural hematoma (6.18, 2.13~17.98), the presence of an epidural hematoma (5.73, 1.18~27.76), and the presence of a basal cistern effacement (10.93, 1.19~99.57). Conclusion: For patients undergoing scanning within 2 hours of injury, the rate of PIH approaches 61%. Early repeated CT scanning is indicated in patients with a nonsurgically-treated hemorrhage revealed on the first CT scan. Worsened GCS score, significant hematoma growth and effacement of the basal cisterns on the initial CT scan are powerful predictors of which patients will require surgery. These findings should be important factors in understanding and managing of PIH.

• The Journal of the Korean bone and joint tumor society
• /
• v.18 no.1
• /
• pp.45-49
• /
• 2012

Skip lesion is not uncommon feature in osteosarcoma and considered to be importantly associated with poor prognosis factor, and thus, should be excised with the main mass. The accurate pre-operative evaluation of the intramedullary extent of osteosarcoma is essential, because it determines the level of bone resection. Among the reliable detection methods, bone scan has a drawback of high rate of false negative results and regional MRI has a difficulty to cover the whole involved lesions without clinical suspicion. The authors report a case of osteosarcoma of the distal femur with a proximal skip lesion that was not detected by either regional MR imaging or by bone scan, but which was visualized by FDG-PET/CT.