• Journal of Biomedical Engineering Research
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• v.39 no.2
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• pp.80-86
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• 2018

The aim of this study were to establish the clinical references and guidelines for the maximum standardized uptake ($SUV_{max}$) value of pancreatic cancer, pancreatitis, and normal pancreas in $^{18}F-FDG$ PET-CT examinations for pancreatic disease. For this purpose, we performed the statistical analysis on the descriptive statistics, percentiles and inter quartiles range (IQR), normal distribution, and using the probability density function for pancreatic cancer, pancreatitis, and normal pancreas. As a result, the clinical reference of $SUV_{max}$ for the pancreatic cancer, pancreatitis, and normal pancreas was more than 3.45, 1.91 to 2.62, and less than 1.91, respectively. Also, optimal cut-off value for applying the dual time point PET-CT examination was determined to be 2.62. The results of this study are summarized as follows: first, we suggests the clinical reference and guideline for the pancreatic cancer, pancreatitis, and normal pancreas, and second, suggests a scientific approach to improve diagnostic accuracy of pancreatic disease by deviating from an approximate experience approach.

• IEMEK Journal of Embedded Systems and Applications
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• v.17 no.5
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• pp.265-272
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• 2022

As the risk of lung cancer has increased, early-stage detection and treatment of cancers have received a lot of attention. Among various medical imaging approaches, computer tomography (CT) has been widely utilized to examine the size and growth rate of lung nodules. However, the process of manual examination is a time-consuming task, and it causes physical and mental fatigue for medical professionals. Recently, many computer-aided diagnostic methods have been proposed to reduce the workload of medical professionals. In recent studies, encoder-decoder architectures have shown reliable performances in medical image segmentation, and it is adopted to predict lesion candidates. However, localizing nodules in lung CT images is a challenging problem due to the extremely small sizes and unstructured shapes of nodules. To solve these problems, we utilize atrous spatial pyramid pooling (ASPP) to minimize the loss of information for a general U-Net baseline model to extract rich representations from various receptive fields. Moreover, we propose mixed-up attention mechanism of reverse, boundary and convolutional block attention module (CBAM) to improve the accuracy of segmentation small scale of various shapes. The performance of the proposed model is compared with several previous attention mechanisms on the LIDC-IDRI dataset, and experimental results demonstrate that reverse, boundary, and CBAM (RB-CBAM) are effective in the segmentation of small nodules.

• Journal of Veterinary Clinics
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• v.40 no.2
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• pp.139-146
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• 2023

Three dogs were referred with epistaxis and facial deformity. Computed tomography (CT) scan identified masses in the bilateral nasal cavity with soft tissue attenuation and contrast enhancement. These masses had caused adjacent bones lysis, especially lysis of cribriform plate that extended to the intracranial region. Base on histopathology and CT imaging results, tumors were diagnosed as nasal carcinomas at stage 4. Three dogs were treated with stereotactic radiation therapy (SRT). These dogs received 30-35 Gy from 3-5 daily treatments (7-10 Gy per treatment). The sizes of tumors decreased the most on follow-up CT images at one month after treatment. Recurrence was confirmed between 3 and 5 months after completing SRT. The survival time of dogs treated with SRT were 110, 190, and 210 days, respectively. This study confirmed that SRT could treat canine nasal carcinomas with cribriform plate lysis without causing serious radiation toxicities. Follow-up CT examination is considered at 1 month and 3 to 6 months after SRT to accurately evaluate the prognosis and the timing of recurrence.

• Archives of Plastic Surgery
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• v.33 no.2
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• pp.175-180
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• 2006

Preoperative angiography is frequently used in the planning of microsurgical reconstruction for identification of vascular abnormality that influence the planning of operation. But, recently 3D CT angiography is considered as new technique that can provide detailed information about vascular anatomy as well as soft and bony tissue without the risks of invasive angiography. 3D CT angiograms were performed in 19 patients before microsurgical reconstruction for the lower extremity and hand between May of 2003 and Oct of 2004. Sixteen of the studies were of the donor site and all of 19 studies were of the recipient site. No complications were found from the 3D CT angiograms. In one case of the bone exposed open wound, the injury of anterior tibial artery was identified and the zone of injury was adequately demonstrated. With the improvement in quality of CT imaging, 3D CT angiograms may provide a favorable alternative to invasive angiography. It is capable of providing high-resolution, three dimensional vascular imaging without the need for arterial puncture and prolonged post-procedure observation. The relation among blood vessels, bones, and soft tissue is well demonstrated in 3D CT angiogram. Also The acquisition time and examination cost were considerably lower in comparison with invasive angiography. In conclusion, this study demonstrates that 3D CT angiography may provide accurate, safe, and cost-effective preoperative imaging. The 3D CT angiography with relatively low morbidity, low cost, ease of image acquisition can have an broader role in microsurgical reconstructive surgery.

• Journal of the Korean Society of Radiology
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• v.10 no.4
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• pp.255-261
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• 2016

In this study, among various factors having influence on SUV, we intended to compare and analyze the change of SUV using CT(4 type) and MRI(3 type) contrast agents which are commercialized now. We used Discovery 690 PET/CT(GE) and NEMA NU2 - 1994 PET phantom as experimental equipment. We have conducted a study as follows; first, we filled distilled water to phantom about two-thirds and injected radioisotope(18F-FDG 37 MBq), contrast agent. Second, we mixed CT contrast agent with distilled water and MRI contrast agent with that water separately. And then, we stirred the fluid and filled distilled water fully not to make air bubble. In emission scan, we had 15minutes scanning time after 40 minutes mixing contrast agent with distilled water. In transmission scan, we used CT scanning and its measurement conditions were tube voltage 120 kVp, tube current 40 mA, rotation time 0.5 sec, slice thickness 3.27 mm, DFOV 30 cm. Analyzing results, we set up some ROIs in 10th, 15th, 20th, 25th, 30th slice and measured SUVmean, SUVmax. Consequently, all images mixed 3 types of MRI contrast agent with distilled water have high SUVmean as compared with pure FDG image but there was no statistical significance. In SUVmax, they have high score and there was statistical significance. And other 4 images mixed 4 types of CT contrast agent with distilled water have significance in both SUVmean and SUVmax. Attenuation correction in PET/CT has been executed through various methods to make high quality image. But we figured out that using CT and MRI contrast agents before PET/CT scanning could make distortion of image and decrease diagnostic value. In that reason, we have to sort out the priority of examination in hospital not to disturb other examination's results. Through this process, we will be able to give superior medical service to our customers.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1649-1654
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• 2013

Objective: This work aimed to evaluate the safety and clinical efficacy of transcatheter arterial chemoembolization (TACE) combined with c-arm cone-beam CT guided synchronous radiofrequency ablation (RFA) in treatment of large hepatocellular carcinoma (HCC). Methods: 21 patients with large HCC were studied from January 2010 to March 2012. TACE combined with synchronous C-arm cone-beam CT guided RFA were performed on a total of 25 lesions. Conventional imaging examination (CEUS, enhanced CT or MRI) and AFP detection were regularly conducted to evaluate the technical success rate of combined treatment, complications, treatment response, time without disease recurrence and survival rate. Results: The technical success rate of combined treatment was 100%, without any significant complication. After 1 month, there were 19 cases with complete response and 2 cases with partial response, with an complete response rate of 90.4% (19/21) and a clinical effective rate of 100% (21/21). The complete response rates of single nodular lesions (100%, 17/17) was significantly higher than that of multiple nodular lesions (50%, 2/4) (P<0. 05). During 2 to 28 months of follow-up, in 19 cases with complete response, the average time without disease recurrence was $10.8{\pm}6$ months. The total survival rates of 6, 12 and 18 months in 21 patients were 100%, respectively. Conclusion: TACE combined with synchronous C-arm CT guided RFA is safe and effective for treatment of large HCC. The treatment efficacy for single nodular lesion is better than that for multiple nodular lesions.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.2
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• pp.68-72
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• 2014

Purpose The nuclear medicine examination, there is a difficulty to carry out the inspection of both on the day of residual isotope due to the half-life. In this study, by studying the mutual influence and $^{18}F$-FDG of $^{99m}TcO_4{^-}$, I would like to explain the matters to be considered in the case of performing the same day. Materials and Methods With the NEMA-1994 Phantom, and experiments were performed 3 times. Create a 1: 4 Background ratio HOT and the $^{99m}TcO_4{^-}$ The first experiment: After underwent SPECT in INFINIA (GE Healthcare, MI, USA), and were injected with $^{18}F$-FDG 37 MBq in the Background area, 13 once for 60 minutes under the same conditions was time Scan. Create a 1: 4 Background ratio HOT and the $^{18}F$-FDG second is: The Scan in PET/CT Discovery 600 (GE Healthcare, MI, USA), and 148 MBq after injection $^{99m}TcO_4{^-}$ the Background area, once for 60 minutes, 6 under the same conditions was time Scan. Create a 1: 4 Background ratio HOT and the $^{18}F$-FDG experiments las, increments of 296 MBq and 148 MBq the 1 Bed Scan after $^{99m}TcO_4{^-}$, was 1 Bed Scan under the same conditions. Non BKG area and HOT, I was measured comparing the Total Counts and SNR or CNR. Results Showed a significant difference in the ratio CNR of enforcement during SPECT $^{18}F$-FDG is, (p>0.05). The $^{99m}TcO_4{^-}$ was no significant difference between the SNR ratio of PET / CT at the time of the effective date (p<0.05). I got the results $^{99m}TcO_4{^-}$ that reduce the Total Counts of PET / CT scan. Conclusion If you make a PET / CT scan, may affect the test using the $^{99m}TcO_4{^-}$ up to 12 hours, when it is performed before the $^{99m}TcO_4{^-}$, does not affect the SNR and SUV, PET / CT scan I reduced the detection efficiency. The inspection of day, we'd like to recommend a way to complement the detection efficiency to increase the inspection time of PET / CT in move forward the inspection using the $^{99m}TcO_4{^-}$.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7193-7196
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• 2013

Ovarian cancer patients need a surveillance program for the detection of tumor progression after completion of treatment. The methods generally consist of history taking, physical examination, tumor marker monitoring and imaging. However, the details of recurrence detection with each method are not well defined. To clarify this issue, ovarian cancer patients who achieved complete or partial responses and developed tumor progression at the follow up time between January 2004 and December 2010 in University Hospital Chiang Mai, Thailand, were reviewed. Clinical data, CA 125 level and imaging results at the tumor progression time were recorded and analyzed. There were 144 ovarian cancer patients meeting the inclusion criteria with the mean age of 51 years and 62.5% of them were in an advanced stage. Complete response was achieved in 89 patients (61.8%) after primary treatment. The median progression free survival and overall survival were 15.5 months and 37.5 months, respectively. Abnormal symptoms presented in 49.3% of the studied patients and 59.7% developed physical examination abnormalities. In addition, CA 125 was elevated in 89.6% while in 74.3% of tumor progression was identified by CT-scan. Short treatment time period and a high level of CA 125 were significant independent prognostic factors in these patients. In conclusion, careful history taking, physical examination and monitoring of CA 125 levels are important methods for tumor progression detection in a surveillance program for epithelial ovarian cancer patients.

• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.1
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• pp.27-32
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• 2008

Purpose: The evaluation of SUV (Standardized Uptake Values) for quantitative analysis in PET exam is the most significant. In PET exam, we make attenuation correction images by using $^{68}Ge$, $^{137}Cs$ or CT data. At this time, a distorted attenuation map affects quantitative analysis. After the exam using barium-sulfate and high density of barium contrast make attenuation map distorted. And then it brings bed influences on SUV. The aim of this study is to verify the relationship between high density barium-sulfate and SUV in PET exam. Materials and Methods By using $^{18}F$-FDG, we made barium-sulfate powder, density of 0, 1.5, 3, 5, 10 and 15% respectively and acquired PET and PET/CT images per each density. And we examined SUV variations from PET and PET/CT images according to differences of barium's density. Moreover, we finally calculated SUV causing variations in HU (Hounsfield Units) values to justify whether the differences of barium density bring any changes in PET/CT exam. Results: From PET images acquired from transmission scan with $^{68}Ge$, we got SUV figures from 6.46 to 6.8 in barium density between 0 to 15 percent. On the other hand, In PET images acquired from Tx scan that using CT, SUV was 6.77 to 23.73, derived from the same barium density. And CT HU values range from 29 to 2004. Conclusion: PET images from Tx data using $^{68}Ge$ weren't affected by barium density and had no differences in SUV. But in the PET/CT images using CT Tx data, there's considerable variations in HU and SUV values according to a difference of barium density in HU values. To perform a precise examination, barium sulfate should be removed from a human body before performing a PET exam.

• The Korean Journal of Emergency Medical Services
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• v.24 no.2
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• pp.99-109
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• 2020

Purpose: Alcohol intoxication is frequently observed in patients with brain hemorrhage. The purpose of this study was to determine whether intoxication affects the Korean Triage and Acuity Stage (KTAS) level and the emergency medical process in emergency departments. Methods: This study was a retrospective observational study enrolled 253 brain hemorrhage patients (47 of those intoxicated) who visited the emergency medical center on public EMS ambulance from January. 1, 2017 to April, 30, 2019. Data were collected through the electronic medical record (EMR). KTAS level and time to computerized tomography (CT) were compared to evaluate whether inebriation affects care and examination processes. All data were analyzed using SPSS program. Results: Of the 47 patients intoxicated patients, 85.1% were male, and 74.5% accompanied by trauma. Initial KTAS level showed significant differences (77.2%; p=.000) when the level 3,4 was not drunk. The average time taken from triage to CT scans showed a significant difference of 24.81±23.72 (min) when the drunken state was not 58.38±56.54 (min)(p=.000). Conclusion: In patients with brain hemorrhage admitted to ED from public EMS, undertriage and delay after initial assessment were detected in inebriated patients. Careful initial evaluation and prompt medical response should be considered for patients transported by EMS.