• Journal of the Korean Society of Radiology
• /
• v.11 no.7
• /
• pp.619-625
• /
• 2017

The sudy was intended to evaluate the optimal equipment selection by quantitatively assessing the SNR(signal to noise ratio) and CNR(contrast to noise ratio) on the abdominal organ. This study performed on 1.5 T and 3.0 T MRI units focusing on HASTE, HASTE(f/s) and FFE(in of phase), FFE(out of phase) without using the contrast medium(Gadolinium). The data analysis was performed by randomly selecting on 1.5 T and 3.0 T abdominal MRI images. As a results, SNR and CNR values of 3.0 T is higher than 1.5 T at liver, kidney and spleen(p<0.05). Stomach, abdominal fat and pancreas was obtained a higher value at 1.5 T(p<0.05). On conclusion, the organs of outer part in the body showed generally a high value at 3.0 T, and the organs of inner part in the body including the gas showed a high value at 3.0 T because of a large difference on magnetic susceptibility.

• Pediatric Infection and Vaccine
• /
• v.23 no.3
• /
• pp.217-222
• /
• 2016

Purpose: This study aimed to identify the differential clinical, laboratory, and imaging characteristics between patients with cervical lymphadenitis as first presentation of Kawasaki disease (CLKD) and those with acute unilateral cervical lymphadenitis (AUCL). Methods: We surveyed 372 patients who visited Pusan National University Children's Hospital because of fever and cervical lymph node enlargement, and underwent neck computed tomography (CT) from January 2010 to December 2014. We compared 28 confirmed cases of Kawasaki disease and 28 cases of AUCL based on a retrospective review of the medical records of the patients. Results: Patients with CLKD and AUCL showed no differential clinical characteristics in terms of the duration of fever, antibiotic use, or the size of lymph nodes. Patients with CLKD had higher white blood cell count, absolute neutrophil count, erythrocyte sedimentation rate, and C-reactive protein levels (P<0.05) than those of patients with AUCL. The presence of retropharyngeal edema on neck CT was similar between the groups (64% vs. 33%, P=0.686). Conclusions: CLKD and AUCL showed no differentiating clinical and radiological characteristics; hence, Kawasaki disease should be the presumptive diagnosis in patients with fever and cervical lymph node enlargements who fail to respond to antibiotic treatment.

• Archives of Craniofacial Surgery
• /
• v.21 no.5
• /
• pp.288-293
• /
• 2020

Background: Pilomatrixoma is a benign tumor that originates from the hair follicle matrix. It usually presents as a hard, slow growing, solitary mass that can be easily misdiagnosed as other skin masses. The aim of this study was to clinically analyze a case series of pilomatrixoma in pediatric patients from Korea. Methods: A total of 165 pediatric patients from 2011 to 2018 with a histological diagnosis of pilomatrixoma were included. A retrospective review was performed using the electronic medical records, including patient demographics, number and location of the mass, clinical and imaging presentation, and postoperative outcomes. Results: There were 61 male and 104 female patients with 152 solitary and 13 multiple pilomatrixomas. Among solitary pilomatrixomas, the lesion commonly occurred in the head and neck (84.2%), followed by upper limbs (11.2%), lower limbs (3.3%), and trunk (1.3%). The pilomatrixoma lesion presented as the following types based on our clinical classification: mass (56.02%), pigmentation (25.31%), mixed (12.65%), ulceration (4.82%), and keloid-like (1.2%). Ultrasonography showed a high positive predictive value (95.56%). There were no specific complications observed except for two cases of recurrence. Conclusion: Pilomatrixoma has various clinical feature presentations and commonly occurs in the head and neck. Ultrasonography is a helpful diagnostic tool. Surgical removal of the lesion is the main treatment method with a low recurrence rate.

• Proceedings of the KIEE Conference
• /
• 2007.04a
• /
• pp.58-60
• /
• 2007

Magnetic Resonance Imaging(MRI) has become a very widely used medical procedur e. Clo.sed and open systems are typically used with static magnetic fields at or below 2 Tesla. BWhole body SAR(specific absorbsion rate) is the value of SAR averaged over the entire body of the patient over any period of 15 minutes. Head SAR is the value of SAR averaged over the head of the patient for any period of 10 minutes. SAR is a measure of the absorption of electromagnetic energy in the body' (typically in watts per kilogram (W/kg)). The normal operating mode comprises values of head SAR not higher than 3 W/kg. The second level controlled operating mode comprises values higher than 3 W/kg. Current FDA guidance limits the SAR in the whole body. including the head to a range of 1.5 to 4.0 W/kg, depending on the patient's clinical condition. SAR, limit restrictions are incorporated in all MRI systems. and domestic' s guidance limits the SAR in a part body. including the head to 3.2w/kg and less. The purpose of this study is to evaluate on change of head SAR in using MRI pulse sequence and to check if exceed 3.2(w/kg) level in domestic a part exposure through measured head SAR. 23 patient's the average head SAR of pulse sequence is that T2WI sagittal is 0.5375. T2WI axial(FSE) is 0.4817, T1WI axial(SE) is, 0.8179. FLAIR axial is 0.4580. GRE axial is 0.0077, Diffusion is 0.0824w/kg. The head SAR exposed per patient was proved 2.3845w/kg less than the international standard. Coefficient of correlation for the relations body weight and SAR or for the relations ETL(echo train length) and SAR is 1 value. Coefficient of correlation for the relations between TR(time to repeat) and SAR is -0.602 value. so SAR increased relative to weight body and ETL. But the relations between TR and SAR is negative definite.

• Investigative Magnetic Resonance Imaging
• /
• v.17 no.1
• /
• pp.26-32
• /
• 2013

Purpose : This study was performed to evaluate the presence and severity of Hill-Sachs (HS) lesions on MR arthrography (MRA) of shoulder in patients with Bankart lesions following anterior dislocation and to investigate their relationship with Bankart lesions and frequency of dislocations. Materials and Methods: 86 MRA of shoulder were evaluated in patients with arthroscopic Bankart repairs following anterior dislocations. The largest surface length of HS lesion on MRA and extent of Bankart lesions on arthroscopy were measured. Relationships between length of HS lesions and extent of Bankart lesions and frequency of dislocations were assessed. Results: HS lesions were identified on MRA in 78 patients. The largest surface length of HS lesion ranged from 9.3 mm to 29.6 mm (mean, 18.8 mm). The extent of Bankart lesion ranged from one to six o'clock extent (mean, 4.25 o'clock extent). Three patients had single dislocation and the other 75 patients had recurrent dislocations (mean 24.5 times). The largest surface length of HS lesions was positively correlated with extent of Bankart lesions (p = 0.001, r = 0.37), but not with frequency of dislocation. Conclusion: HS lesion was very common in patients with Bankart lesion. The severity of HS lesions was correlated with extent of Bankart lesions.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.3
• /
• pp.1065-1068
• /
• 2012

Background: Liver cancer is the most frequent cancer among Thais especially people in northeastern Thailand, but there has as yet been no assessment of trend. The data of all cancers in Khon Kaen can be retrieved from data base of the Khon Kaen Cancer Registry (KKCR) which was established in 1984. Objective: To assess the incidence trend of hepatocellular carcinoma in Khon Kaen, Thailand, between 1990 and 2009. Methods: Population-based cases of liver cancer registered between 1985 and 2009 were retrieved from the KKCR data base and cases with diagnosis of hepatocellular carcinoma (HCC) with the coding C22.0 according to ICD-O were selected. Incidence trends were calculated using the Jointpoint analysis. Results: There were 7,859 cases of HCC during the study period. Males were affected two times more frequently than females. The most common age group of cases was 50 and 69 years (60.3%). Most patients were diagnosed based on radiology imaging (40.6%) while the morphology verification was 7%. The age-standardized rates (ASR) were 13.1 to 49.8 per 100,000 among males and 4.8 to 38.4 per 100,000 among females depending on year of diagnosis since 1985. Remarkably, the ASRs were clearly low during first few years of starting the registration. The overall ASRs of HCC were 30.3 per 100,000 in males (95% CI: 25.9 to 34.6) and 13.1 per 100,000 (95% CI: 10.4 to 15.8) in females. During 1990-2009, the trends in incidences have been decreasing significantly with the annual percent change (APC) of 6.2% per year (95% CI: -7.6 to -4.8) in males and by 6.5% per year in females (95% CI: -8.4 to -4.9). Conclusions: The incidence trends have been decreasing in both sexes. The recent decline in incidence may represent a falling risk.

• Journal of Korean Neurosurgical Society
• /
• v.51 no.4
• /
• pp.215-218
• /
• 2012

Objective: Traumatic epidural hematomas (EDHs) in children are a relatively unusual occurrence. The cause and outcome vary depending on period and reg ion of study. The aims of this analysis were to review the cause and outcome of pediatric EDHs nowadays and to discuss outcome-related variables in a large consecutive series of surgically treated EDH in children. Methods: This is a retrospective review of 29 patients with surgically treated EDHs between Jan 2000 and February 2010. Patients' medical records, computed tomographic (Cl) scans, and, if performed, magnetic resonance imaging (MRI) were reviewed to define variables associated with outcome. Variables included in the analysis were age, associated severe intracranial injury, abnormal pupillary response, hematoma thickness, severity of head injury (Glasgow Coma Scale score), parenchymal brain injury, and diffuse axonal injury. Results: The mean (SO) age of the patients was 109 months (0-185 months). Most of the injuries with EDHs occurred in traffic accident (14 cases, 48.2%) and followed by slip down in 6 cases and falls in 6 cases. There were one birth injury and one unknown cause. EDHs in traffic accidents occurred in pedestrians hit by a motor vehicle, 9 cases; motorbike and car accidents, 5 cases and bicycle accidents, 1 case. The locations of hematoma were almost same in both sides (left side in 15 cases). Temporal lobe is the most common site of hematomas (13 cases, 44%). The mean size of the EDHs was 18 mm (range, 5-40 mm). Heterogeneous hematomas in CT scans were 20 cases (67%). Two patients were referred with unilateral or bilateral dilated pupil(s). There was enlargement of EDH in 5 patients (17%). All of them were heterogeneous hematomas in CT scans. Except for 4 patients, all EDHs were associated with skull fracture(s) (87%). There was no case of patient with major organ injury. CT or MRI revealed brain contusion in 5 patients, and diffuse axonal injury in one patient The mortality was zero, and the outcomes were excellent in 26 and good in 2 patients. None of the tested variables were found to have a prognostic relevance. Conclusion: Regardless of the EDH size, the clinical status of the patients, the abnormal pupillary findings, or the cause of injury, the outcome and prognosis of the patients with EDH were excellent.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.9
• /
• pp.5107-5110
• /
• 2013

Background: Among women with haematuria, defining individuals under high risk for bladder cancer based on reproductive factors prior to cystoscopy would be of great benefit in the management of this condition. The aim of this study was to compare age and reproductive factors such as menopausal status, parity, age at first delivery and age at the last delivery between women who have haematuria with or without bladder cancer. Materials and Methods: A total of 463 patients underwent diagnostic cystoscopy in D$\ddot{u}$zce University Faculty of Medicine between 1 June 2008 and 1 June 2013. Female patients who presented with persistent microscopic or macroscopic haematuria and underwent standard evaluation for haematuria including urinalysis, urine culture, urine cytology, urinary tract imaging with excretory urography or computerized tomography with contrast enhancement and endoscopic evaluation of the urethra and bladder were included in this study. Exclusion criteria were tobacco use and high risk occupations for bladder cancer such as textile, dry cleaning, painting and etc. Forteen women had hematuria due to benign conditions, and 18 due to bladder cancer. Data were retrospectively retrieved from the medical records of Duzce University Hospital. Results: Patients with haematuria due to benign reasons did not significantly differ from patients who were found to have bladder cancer in terms of age (p=0.28), menopausal status (p=0.29), mean parity (p=0.38), being nulliparous (p=0.57), parity ${\geq}3$ (p=0.22), age ${\leq}18$ years at first delivery (p=1.00), age ${\geq}30$ years at last delivery (p=0.26), age ${\geq}35$ years at last delivery (p=0.23) and percentage of the patients with advanced age (${\geq}65$ years) (p=0.18). Conclusions: It is difficult to predict a high risk for developing bladder cancer in women with haematuria based solely on reproductive factors.

• Investigative Magnetic Resonance Imaging
• /
• v.4 no.2
• /
• pp.113-119
• /
• 2000

Purpose : To know the possibility of clinical application of MRI using oxygen inhalation as a perfusion MRI Materials and methods : Two healthy volunteers and three patients of one moyamoya disease, one acute infarction and one meningioma were studied using a 1.5 Tesla MRI unit. Oxygen (15 liters/min) mixed with room air was given using face mask from 8 second to 35 second during the study. Images were acquired 25 times (scan time per study were 1.6 seconds) using susceptibility contrast EPI (echo planar image) sequence. Difference maps were acquired by early (study 12-18), and late (study 19-25) O2 inhalation image groups minus pre-O2 inhalation image group (study 3-9) with a Z-score of 0.7-1.0 using VB31C program of Magneton Vision. The resulting perfusion images were created by superimposition of difference maps on corresponding T1 weighted anatomic images. On moyamoya patient, similar perfusion images were acquired after Gd-DTPA injection, and compared with O2 inhalation perfusion images. Results ; The author can get the perfusion images of the brain by oxygen inhalation with susceptibility contrast EPI sequence at the volunteers, and the patient of moyomoya disease, acute infarction and meningioma. On moyamoya patient, perfusion images with O2 inhalation are similar with perfusion images by Gd-DTPA injection. Conclusion 1 This study has demonstrated that the susceptibility contrast EPI by oxygen inhalation can be used as the clinically useful perfusion MRI technique

• Investigative Magnetic Resonance Imaging
• /
• v.22 no.3
• /
• pp.150-157
• /
• 2018

Purpose: To assess associations between morphological characteristics of intracranial arteries in time-of-flight MR angiography (TOF-MRA) and atherosclerotic risk factors. Materials and Methods: From January 2014 to October 2015, a total of 129 patients (65 men and 64 women) without intracranial arterial stenosis > 50% were included in this study. All MRIs were performed using a 3T machine with 3D TOF-MRA sequences. We evaluated irregularity, tortuosity, and dilatation of intracranial arteries in maximal intensity projection (MIP) of TOF-MRA. Subjects' risk factors for atherosclerosis including history of hypertension and diabetes were collected by reviewing their medical records. Associations between morphological characteristics and each known atherosclerosis risk factor were examined using univariate regression analysis. Multivariate regression models were built to determine combined association between those risk factors and morphologic changes of intracranial arteries. Results: In multivariate analysis, hypertension (coefficient [95% CI]: 0.162 [0.036, 0.289], P = 0.012) and absence of diabetes (coefficient [95% CI]: -0.159 [-0.296, -0.023], P = 0.022) were associated with large diameter of intracranial arteries. Males (coefficient [95% CI]: 0.11 [-0.006, 0.23], P = 0.062) and higher age (coefficient [95% CI]: 0.003 [-0.001, 0.008], P = 0.138) had marginal association with increased diameter. Tortuosity was associated with old age (OR: 1.04 [1.02, 1.07], P < 0.001). Irregular contour of intracranial arteries was significantly associated with old age (OR: 1.05 [1.02, 1.09], P = 0.004), presence of diabetes (OR: 2.88 [1.36, 6.15], P = 0.0058), and previous ischemic stroke (OR: 3.91 [1.41, 11.16], P = 0.0092). Conclusion: Morphological characteristics (irregularity, tortuosity, dilatation) of intracranial arteries seen in TOF-MRA might be associated with atherosclerotic risk factors in subjects with no or mild stenosis.