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1.
Korean Journal of Radiology ; : 333-342, 2022.
Article in English | WPRIM | ID: wpr-926762

ABSTRACT

Objective@#Intracranial atherosclerotic stroke occurs through various mechanisms, mainly by artery-to-artery embolism (AA) or branch occlusive disease (BOD). This study evaluated the spatial relationship between middle cerebral artery (MCA) plaques and perforating arteries among different MCA territory infarction types using vessel wall magnetic resonance imaging (VW-MRI). @*Materials and Methods@#We retrospectively enrolled patients with acute MCA infarction who underwent VW-MRI. Thirty-four patients were divided into three groups according to infarction pattern: 1) BOD, 2) both BOD and AA (BOD-AA), and 3) AA.To determine the factors related to BOD, the BOD and BOD-AA groups were combined into one group (with striatocapsular infarction [BOD+]) and compared with the AA group. To determine the factors related to AA, the BOD-AA and AA groups were combined into another group (with cortical infarction [AA+]) and compared with the BOD group. Plaque morphology and the spatial relationship between the perforating artery orifice and plaque were evaluated both quantitatively and qualitatively. @*Results@#The plaque margin in the BOD+ group was closer to the perforating artery orifice than that in the AA group (p = 0.011), with less enhancing plaque (p = 0.030). In the BOD group, plaques were mainly located on the dorsal (41.2%) and superior (41.2%) sides where the perforating arteries mainly arose. No patient in the AA group had overlapping plaques with perforating arteries at the cross-section where the perforator arose. Perforating arteries associated with culprit plaques were most frequently located in the middle two-thirds of the M1 segment (41.4%). The AA+ group had more stenosis (%) than the BOD group (39.73 ± 24.52 vs. 14.42 ± 20.96; p,/i> = 0.003). @*Conclusion@#The spatial relationship between the perforating artery orifice and plaque varied among different types of MCA territory infarctions. In patients with BOD, the plaque margin was closer and blocked the perforating artery orifice, and stenosis degree and enhancement were less than those in patients with AA.

2.
Yonsei Medical Journal ; : 1052-1061, 2021.
Article in English | WPRIM | ID: wpr-904271

ABSTRACT

Purpose@#This study aimed to investigate whether a deep learning model for automated detection of unruptured intracranial aneurysms on time-of-flight (TOF) magnetic resonance angiography (MRA) can achieve a target diagnostic performance comparable to that of human radiologists for approval from the Korean Ministry of Food and Drug Safety as an artificial intelligence-applied software. @*Materials and Methods@#In this single-center, retrospective, confirmatory clinical trial, the diagnostic performance of the model was evaluated in a predetermined test set. After sample size estimation, the test set consisted of 135 aneurysm-containing examinations with 168 intracranial aneurysms and 197 aneurysm-free examinations. The target sensitivity and specificity were set as 87% and 92%, respectively. The patient-wise sensitivity and specificity of the model were analyzed. Moreover, the lesion-wise sensitivity and false-positive detection rate per case were also investigated. @*Results@#The sensitivity and specificity of the model were 91.11% [95% confidence interval (CI): 84.99, 95.32] and 93.91% (95% CI:89.60, 96.81), respectively, which met the target performance values. The lesion-wise sensitivity was 92.26%. The overall falsepositive detection rate per case was 0.123. Of the 168 aneurysms, 13 aneurysms from 12 examinations were missed by the model. @*Conclusion@#The present deep learning model for automated detection of unruptured intracranial aneurysms on TOF MRA achieved the target diagnostic performance comparable to that of human radiologists. With high standalone performance, this model may be useful for accurate and efficient diagnosis of intracranial aneurysm.

3.
The Korean Journal of Helicobacter and Upper Gastrointestinal Research ; : 220-225, 2021.
Article in Korean | WPRIM | ID: wpr-903650

ABSTRACT

Background/Aims@#Studies in healthy humans have reported that the addition of mosapride to acid suppressants resulted in higher intragastric pH than acid suppressant administration alone. We investigated the effect of the addition of mosapride to famotidine on the intragastric pH and gastric emptying rate (GER) in rats. @*Materials and Methods@#Sixty male Wistar rats were used in this study. Experimental groups were divided into control, famotidine-only, mosapride-only, and famotidine with mosapride (combination). The first experiment was performed in non-stressed rats. Mosapride was administered by oral gavage 1 hour before the meal, and famotidine was administered just before the meal. The rats were provided with food for 30 minutes. The intragastric pH was measured under isoflurane anesthesia, and the GER was measured after harvesting the stomach. In the stress experiment, rats were exposed to 1-hour restraint stress immediately after mosapride administration and subjected to the same process as in the experiment with the non-stressed rats. @*Results@#The famotidine-only and combination groups showed significantly higher gastric pH levels than the control group in non-stressed (P<0.01 and P<0.001, respectively) and stressed (P<0.001 and P<0.001, respectively) rats. The combination group also showed significantly higher intragastric pH levels than the famotidine-only group in non-stressed (P<0.01) and stressed (P<0.05) rats. Additionally, combination groups showed a significantly higher GER than the famotidine-only group in non-stressed (P<0.001) and stressed (P<0.01) rats. @*Conclusions@#The combination of mosapride with famotidine significantly increased intragastric pH compared to famotidine alone in the non-stressed and stressed rats.

4.
Yonsei Medical Journal ; : 1052-1061, 2021.
Article in English | WPRIM | ID: wpr-896567

ABSTRACT

Purpose@#This study aimed to investigate whether a deep learning model for automated detection of unruptured intracranial aneurysms on time-of-flight (TOF) magnetic resonance angiography (MRA) can achieve a target diagnostic performance comparable to that of human radiologists for approval from the Korean Ministry of Food and Drug Safety as an artificial intelligence-applied software. @*Materials and Methods@#In this single-center, retrospective, confirmatory clinical trial, the diagnostic performance of the model was evaluated in a predetermined test set. After sample size estimation, the test set consisted of 135 aneurysm-containing examinations with 168 intracranial aneurysms and 197 aneurysm-free examinations. The target sensitivity and specificity were set as 87% and 92%, respectively. The patient-wise sensitivity and specificity of the model were analyzed. Moreover, the lesion-wise sensitivity and false-positive detection rate per case were also investigated. @*Results@#The sensitivity and specificity of the model were 91.11% [95% confidence interval (CI): 84.99, 95.32] and 93.91% (95% CI:89.60, 96.81), respectively, which met the target performance values. The lesion-wise sensitivity was 92.26%. The overall falsepositive detection rate per case was 0.123. Of the 168 aneurysms, 13 aneurysms from 12 examinations were missed by the model. @*Conclusion@#The present deep learning model for automated detection of unruptured intracranial aneurysms on TOF MRA achieved the target diagnostic performance comparable to that of human radiologists. With high standalone performance, this model may be useful for accurate and efficient diagnosis of intracranial aneurysm.

5.
The Korean Journal of Helicobacter and Upper Gastrointestinal Research ; : 220-225, 2021.
Article in Korean | WPRIM | ID: wpr-895946

ABSTRACT

Background/Aims@#Studies in healthy humans have reported that the addition of mosapride to acid suppressants resulted in higher intragastric pH than acid suppressant administration alone. We investigated the effect of the addition of mosapride to famotidine on the intragastric pH and gastric emptying rate (GER) in rats. @*Materials and Methods@#Sixty male Wistar rats were used in this study. Experimental groups were divided into control, famotidine-only, mosapride-only, and famotidine with mosapride (combination). The first experiment was performed in non-stressed rats. Mosapride was administered by oral gavage 1 hour before the meal, and famotidine was administered just before the meal. The rats were provided with food for 30 minutes. The intragastric pH was measured under isoflurane anesthesia, and the GER was measured after harvesting the stomach. In the stress experiment, rats were exposed to 1-hour restraint stress immediately after mosapride administration and subjected to the same process as in the experiment with the non-stressed rats. @*Results@#The famotidine-only and combination groups showed significantly higher gastric pH levels than the control group in non-stressed (P<0.01 and P<0.001, respectively) and stressed (P<0.001 and P<0.001, respectively) rats. The combination group also showed significantly higher intragastric pH levels than the famotidine-only group in non-stressed (P<0.01) and stressed (P<0.05) rats. Additionally, combination groups showed a significantly higher GER than the famotidine-only group in non-stressed (P<0.001) and stressed (P<0.01) rats. @*Conclusions@#The combination of mosapride with famotidine significantly increased intragastric pH compared to famotidine alone in the non-stressed and stressed rats.

6.
Yonsei Medical Journal ; : 1125-1135, 2021.
Article in English | WPRIM | ID: wpr-919589

ABSTRACT

Purpose@#This study aimed to propose an effective end-to-end process in medical imaging using an independent task learning (ITL) algorithm and to evaluate its performance in maxillary sinusitis applications. @*Materials and Methods@#For the internal dataset, 2122 Waters’ view X-ray images, which included 1376 normal and 746 sinusitis images, were divided into training (n=1824) and test (n=298) datasets. For external validation, 700 images, including 379 normal and 321 sinusitis images, from three different institutions were evaluated. To develop the automatic diagnosis system algorithm, four processing steps were performed: 1) preprocessing for ITL, 2) facial patch detection, 3) maxillary sinusitis detection, and 4) a localization report with the sinusitis detector. @*Results@#The accuracy of facial patch detection, which was the first step in the end-to-end algorithm, was 100%, 100%, 99.5%, and 97.5% for the internal set and external validation sets #1, #2, and #3, respectively. The accuracy and area under the receiver operating characteristic curve (AUC) of maxillary sinusitis detection were 88.93% (0.89), 91.67% (0.90), 90.45% (0.86), and 85.13% (0.85) for the internal set and external validation sets #1, #2, and #3, respectively. The accuracy and AUC of the fully automatic sinusitis diagnosis system, including site localization, were 79.87% (0.80), 84.67% (0.82), 83.92% (0.82), and 73.85% (0.74) for the internal set and external validation sets #1, #2, and #3, respectively. @*Conclusion@#ITL application for maxillary sinusitis showed reasonable performance in internal and external validation tests, compared with applications used in previous studies.

7.
Annals of Dermatology ; : 155-158, 2020.
Article in English | WPRIM | ID: wpr-811081

ABSTRACT

Solitary fibrous tumors (SFT) are uncommon mesenchymal tumors. SFT have several synonyms including localized fibrous tumor, benign mesothelioma, localized fibrous mesothelioma, and submesothelial fibroma. SFT usually occur in the pleura or other serosal surfaces, but SFT can also develop in extrapleural areas including the nasal cavity, orbit, retroperitoneum, and pelvis. Cutaneous SFT is extremely rare, and more likely to occur in the head and neck region. Histologically, this tumor can mimic a variety of benign and malignant tumors such as dermatofibroma, dermatofibrosarcoma protuberans, spindle cell lipoma or other mesenchymal tumors. Most cases of SFT show non-aggressive clinical courses, with low recurrence rates. Herein, we describe a case of primary cutaneous SFT which presented with huge mass on the back.


Subject(s)
Dermatofibrosarcoma , Head , Histiocytoma, Benign Fibrous , Lipoma , Mesothelioma , Nasal Cavity , Neck , Orbit , Pelvis , Pleura , Recurrence , Skin , Solitary Fibrous Tumor, Pleural , Solitary Fibrous Tumors
8.
Korean Journal of Radiology ; : 1339-1349, 2020.
Article in English | WPRIM | ID: wpr-902391

ABSTRACT

Objective@#Compressed sensing (CS) has gained wide interest since it accelerates MRI acquisition. We aimed to compare the 3D post-contrast T1-weighted volumetric isotropic turbo spin echo acquisition (VISTA) with CS (VISTA-CS) and without CS (VISTA-nonCS) in intracranial vessel wall MRIs (VW-MRI). @*Materials and Methods@#From April 2017 to July 2018, 72 patients who underwent VW-MRI, including both VISTA-CS and VISTAnonCS, were retrospectively enrolled. Wall and lumen volumes, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured from normal and lesion sites. Two neuroradiologists independently evaluated overall image quality and degree of normal and lesion wall delineation with a four-point scale (scores ≥ 3 defined as acceptable). @*Results@#Scan coverage was increased in VISTA-CS to cover both anterior and posterior circulations with a slightly shorter scan time compared to VISTA-nonCS (approximately 7 minutes vs. 8 minutes). Wall and lumen volumes were not significantly different with VISTA-CS or VISTA-nonCS (interclass correlation coefficient = 0.964–0.997). SNR was or trended towards significantly higher values in VISTA-CS than in VISTA-nonCS. At normal sites, CNR was not significantly different between two sequences (p = 0.907), whereas VISTA-CS provided lower CNR in lesion sites compared with VISTA-nonCS (p = 0.003). Subjective wall delineation was superior with VISTA-nonCS than with VISTA-CS (p = 0.019), although overall image quality did not differ (p = 0.297). The proportions of images with acceptable quality were not significantly different between VISTA-CS (83.3–97.8%) and VISTA-nonCS (75–100%). @*Conclusion@#CS may be useful for intracranial VW-MRI as it allows for larger scan coverage with slightly shorter scan time without compromising image quality.

9.
Korean Journal of Radiology ; : 1339-1349, 2020.
Article in English | WPRIM | ID: wpr-894687

ABSTRACT

Objective@#Compressed sensing (CS) has gained wide interest since it accelerates MRI acquisition. We aimed to compare the 3D post-contrast T1-weighted volumetric isotropic turbo spin echo acquisition (VISTA) with CS (VISTA-CS) and without CS (VISTA-nonCS) in intracranial vessel wall MRIs (VW-MRI). @*Materials and Methods@#From April 2017 to July 2018, 72 patients who underwent VW-MRI, including both VISTA-CS and VISTAnonCS, were retrospectively enrolled. Wall and lumen volumes, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured from normal and lesion sites. Two neuroradiologists independently evaluated overall image quality and degree of normal and lesion wall delineation with a four-point scale (scores ≥ 3 defined as acceptable). @*Results@#Scan coverage was increased in VISTA-CS to cover both anterior and posterior circulations with a slightly shorter scan time compared to VISTA-nonCS (approximately 7 minutes vs. 8 minutes). Wall and lumen volumes were not significantly different with VISTA-CS or VISTA-nonCS (interclass correlation coefficient = 0.964–0.997). SNR was or trended towards significantly higher values in VISTA-CS than in VISTA-nonCS. At normal sites, CNR was not significantly different between two sequences (p = 0.907), whereas VISTA-CS provided lower CNR in lesion sites compared with VISTA-nonCS (p = 0.003). Subjective wall delineation was superior with VISTA-nonCS than with VISTA-CS (p = 0.019), although overall image quality did not differ (p = 0.297). The proportions of images with acceptable quality were not significantly different between VISTA-CS (83.3–97.8%) and VISTA-nonCS (75–100%). @*Conclusion@#CS may be useful for intracranial VW-MRI as it allows for larger scan coverage with slightly shorter scan time without compromising image quality.

10.
Korean Journal of Radiology ; : 171-179, 2019.
Article in English | WPRIM | ID: wpr-719586

ABSTRACT

OBJECTIVE: For localization of the motor cortex, seed-based resting-state functional MRI (rsfMRI) uses the contralateral motor cortex as a seed. However, research has shown that the location of the motor cortex could differ according to anatomical variations. The purpose of this study was to compare the results of rsfMRI using two seeds: a template seed (the anatomically expected location of the contralateral motor cortex) and a functional seed (the actual location of the contralateral motor cortex determined by task-based functional MRI [tbfMRI]). MATERIALS AND METHODS: Eight patients (4 with glioma, 3 with meningioma, and 1 with arteriovenous malformation) and 9 healthy volunteers participated. For the patients, tbfMRI was performed unilaterally to activate the healthy contralateral motor cortex. The affected ipsilateral motor cortices were mapped with rsfMRI using seed-based and independent component analysis (ICA). In the healthy volunteer group, both motor cortices were mapped with both-hands tbfMRI and rsfMRI. We compared the results between template and functional seeds, and between the seed-based analysis and ICA with visual and quantitative analysis. RESULTS: For the visual analysis, the functional seed showed significantly higher scores compared to the template seed in both the patients (p = 0.002) and healthy volunteers (p < 0.001). Although no significant difference was observed between the functional seed and ICA, the ICA results showed significantly higher scores than the template seed in both the patients (p = 0.01) and healthy volunteers (p = 0.005). In the quantitative analysis, the functional seed exhibited greater similarity to tbfMRI than the template seed and ICA. CONCLUSION: Using the contralateral motor cortex determined by tbfMRI as a seed could enhance visual delineation of the motor cortex in seed-based rsfMRI.


Subject(s)
Humans , Brain Mapping , Brain Neoplasms , Glioma , Healthy Volunteers , Magnetic Resonance Imaging , Meningioma , Motor Cortex
11.
Korean Journal of Radiology ; : 662-670, 2019.
Article in English | WPRIM | ID: wpr-741434

ABSTRACT

OBJECTIVE: A developmental venous anomaly (DVA) is a vascular malformation of ambiguous clinical significance. We aimed to quantify the susceptibility of draining veins (χvein) in DVA and determine its significance with respect to oxygen metabolism using quantitative susceptibility mapping (QSM). MATERIALS AND METHODS: Brain magnetic resonance imaging of 27 consecutive patients with incidentally detected DVAs were retrospectively reviewed. Based on the presence of abnormal hyperintensity on T2-weighted images (T2WI) in the brain parenchyma adjacent to DVA, the patients were grouped into edema (E+, n = 9) and non-edema (E−, n = 18) groups. A 3T MR scanner was used to obtain fully flow-compensated gradient echo images for susceptibility-weighted imaging with source images used for QSM processing. The χvein was measured semi-automatically using QSM. The normalized χvein was also estimated. Clinical and MR measurements were compared between the E+ and E− groups using Student's t-test or Mann-Whitney U test. Correlations between the χvein and area of hyperintensity on T2WI and between χvein and diameter of the collecting veins were assessed. The correlation coefficient was also calculated using normalized veins. RESULTS: The DVAs of the E+ group had significantly higher χvein (196.5 ± 27.9 vs. 167.7 ± 33.6, p = 0.036) and larger diameter of the draining veins (p = 0.006), and patients were older (p = 0.006) than those in the E− group. The χvein was also linearly correlated with the hyperintense area on T2WI (r = 0.633, 95% confidence interval 0.333–0.817, p < 0.001). CONCLUSION: DVAs with abnormal hyperintensity on T2WI have higher susceptibility values for draining veins, indicating an increased oxygen extraction fraction that might be associated with venous congestion.


Subject(s)
Humans , Brain , Edema , Hyperemia , Magnetic Resonance Imaging , Metabolism , Oxygen , Retrospective Studies , Vascular Malformations , Veins
12.
Korean Journal of Radiology ; : 1138-1145, 2019.
Article in English | WPRIM | ID: wpr-760287

ABSTRACT

OBJECTIVE: To compare apparent diffusion coefficients (ADCs) of brain segments by using two diffusion-weighted imaging acquisition modes, single-shot echo-planar imaging (ss-EPI) and read-out-segmented echo-planar imaging (rs-EPI), and to assess their correlation and agreement in healthy controls. MATERIALS AND METHODS: T2-weighted (T2W) images, rs-EPI, and ss-EPI of 30 healthy subjects were acquired using a 3T magnetic resonance scanner. The T2W images were co-registered to the rs-EPI and ss-EPI, which were then segmented into the gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) to generate masking templates. ADC maps of rs-EPI and ss-EPI were also segmented into the GM, WM, and CSF by using the generated templates. ADCs of rs-EPI and ss-EPI were compared using Student's t tests and correlated using Pearson's correlation coefficients. Bland-Altman plots were used to assess the agreement between acquisitions.


Subject(s)
Brain , Cerebrospinal Fluid , Diffusion , Echo-Planar Imaging , Gray Matter , Healthy Volunteers , Magnetic Resonance Imaging , Masks , White Matter
13.
Investigative Magnetic Resonance Imaging ; : 150-157, 2018.
Article in English | WPRIM | ID: wpr-740145

ABSTRACT

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.


Subject(s)
Humans , Male , Angiography , Arteries , Atherosclerosis , Constriction, Pathologic , Dilatation , Hypertension , Magnetic Resonance Imaging , Medical Records , Multivariate Analysis , Risk Factors , Stroke
14.
Journal of the Korean Radiological Society ; : 249-258, 2018.
Article in English | WPRIM | ID: wpr-916603

ABSTRACT

PURPOSE@#To assess the added prognostic value of the morphologic characteristics of intracranial arteries in the risk modeling of a future non-cardioembolic stroke.@*MATERIALS AND METHODS@#This retrospective study included 86 patients without acute ischemic stroke who first underwent magnetic resonance imaging (MRI) including the time-of-flight magnetic resonance angiography (TOF-MRA) at 3T. Diffusion-weighted imaging (DWI) was performed for the follow-up imaging of these patients > 120 days after the initial MRI. The TOF-MRA result was used to analyze three morphological characteristics: dilatation, stenosis, and tortuosity. The presence of acute ischemic stroke was assessed using the follow-up DWI data. We built two prognostic models: model 1 includes the conventional stroke-risk factors, while model 2 includes the conventional risk factors and the morphologic characteristics of the intracranial arteries. We used the likelihood-ratio test to compare these two models. The models' performances were evaluated using Harrell's concordance index.@*RESULTS@#Fourteen patients suffered non-cardioembolic strokes. The performances of the two models differed significantly regarding the future-risk modeling of the non-cardioembolic stroke (p = 0.031). The Harrell's concordance index of model 2 (0.78 ± 0.05) exceeded that of model 1 (0.72 ± 0.07).@*CONCLUSION@#In addition to the conventional stroke-risk factors, the morphologic characteristics of the intracranial arteries were useful in the modeling of the future risk of the non-cardioembolic ischemic stroke.

15.
Investigative Magnetic Resonance Imaging ; : 171-176, 2017.
Article in English | WPRIM | ID: wpr-107502

ABSTRACT

PURPOSE: To compare different MR sequences for quantification of gadolinium concentration. MATERIALS AND METHODS: Gadolinium contrast agents were diluted into 36 different concentrations. They were scanned using gradient echo (GRE) and ultrashort echo time (UTE) and R1, R2* and phase values were estimated from collected data. For analysis, ROI masks were made for each concentration and then ROI value was measured by mean and standard deviation from the estimated quantitative maps. Correlation analysis was performed and correlation coefficient was calculated. RESULTS: Using GRE sequence, R1 showed a strong linear correlation at concentrations of 10 mM or less, and R2* showed a strong linear correlation between 10 to 100 mM. The phase of GRE generally exhibited a negative linear relationship for concentrations of 100 mM or less. In the case of UTE, the phase had a strong negative linear relationship at concentrations 100 mM or above. CONCLUSION: R1, which was calculated by conventional GRE, showed a high performance of quantification for lower concentrations, with a correlation coefficient of 0.966 (10 mM or less). R2* showed stronger potential for higher concentrations with a correlation coefficient of 0.984 (10 to 100 mM), and UTE phase showed potential for even higher concentrations with a correlation coefficient of 0.992 (100 mM or above).


Subject(s)
Contrast Media , Gadolinium , Masks
16.
Korean Journal of Dermatology ; : 394-400, 2017.
Article in Korean | WPRIM | ID: wpr-107250

ABSTRACT

BACKGROUND: Condyloma acuminatum is a sexually transmitted disease (STD) associated with the human papillomavirus (HPV). Although it is a relatively common disease, there has been no epidemiological and clinical study of condyloma acuminatum performed in Korea since 1978. OBJECTIVE: We aimed to evaluate the clinical features of condyloma acuminatum in Korean patients, to identify the genotypes of HPV, as well as determine factors associated with recurrence of condyloma acuminatum. METHODS: We studied 80 patients (60 men and 20 women) diagnosed with condyloma acuminatum. We analyzed age, sex, duration of the disease, number and locations of lesions, underlying diseases and co-infection with STDs, treatment modalities, and number of relapses. Additionally, 26 patients were analyzed for HPV subtypes. We also evaluated factors affecting recurrence of condyloma. RESULTS: Mean age at the time of diagnosis was 36.9±17.7 years and mean duration of disease was 7.2±16.5 months. The most common sites of involvement were found to be the penile shaft in men and the labia majora in women. We observed that 28 patients showed relapse with a mean duration of 1.5±4.5 months. HPV genotyping revealed that type 6, 11, and 44 genotypes that are associated with a low risk of malignancy were detected in 76.9% of cases, and type 16, 18, 51, 52, and 66 genotypes associated with a high risk of malignancy were detected in 15.3% cases. A significant relationship was observed between the recurrence rates of condyloma acuminatum and the rates of co-infection with STDs and the number of lesions. CONCLUSION: We report a recent epidemiological and clinical review analyzing genotypes of HPV in Korean patients presenting with condyloma acuminatum.


Subject(s)
Female , Humans , Male , Clinical Study , Coinfection , Diagnosis , Genotype , Korea , Recurrence , Sexually Transmitted Diseases
17.
Korean Journal of Dermatology ; : 449-453, 2017.
Article in Korean | WPRIM | ID: wpr-107242

ABSTRACT

Candida famata previously called Torulopsis famata or Debaryomyces hansenii, is usually found in natural substrates. It was earlier considered nonpathogenic in humans; however, a number of clinical cases of human infection have been reported showing isolation of this yeast. Dermatologic literature contains only a few reports regarding cutaneous infection caused by Candida famata. An 18-year old woman presented with a 4-month history of a 4.0×3.0 cm sized erythematous erosive patch on her left sole. A skin biopsy revealed numerous spores and hyphae in the epidermis. Histopathological specimens showed positive findings using the Periodic acid-Schiff and Gomori methenamine silver stains but negative findings using acid-fast bacilli stain. Cultures from skin scrapings yielded numerous colonies. Identification of the fungus was processed up to species level using VITEK 2 (bioMérieux, Inc. Hazelwood, MO, USA), and Candida famata was isolated. She was administered itraconazole at a dose of 200 mg once daily, and following 5 weeks of therapy, the erosive lesion was noted to have completely healed with postinflammatory hyperpigmentation.


Subject(s)
Female , Humans , Biopsy , Candida , Candidiasis, Cutaneous , Coloring Agents , Epidermis , Fungi , Hyperpigmentation , Hyphae , Itraconazole , Methenamine , Skin , Spores , Yeasts
18.
Korean Journal of Radiology ; : 383-391, 2017.
Article in English | WPRIM | ID: wpr-36759

ABSTRACT

OBJECTIVE: The purpose of this study was to compare the histogram analysis and visual scores in 3T MRI assessment of middle cerebral arterial wall enhancement in patients with acute stroke, for the differentiation of parent artery disease (PAD) from small artery disease (SAD). MATERIALS AND METHODS: Among the 82 consecutive patients in a tertiary hospital for one year, 25 patients with acute infarcts in middle cerebral artery (MCA) territory were included in this study including 15 patients with PAD and 10 patients with SAD. Three-dimensional contrast-enhanced T1-weighted turbo spin echo MR images with black-blood preparation at 3T were analyzed both qualitatively and quantitatively. The degree of MCA stenosis, and visual and histogram assessments on MCA wall enhancement were evaluated. A statistical analysis was performed to compare diagnostic accuracy between qualitative and quantitative metrics. RESULTS: The degree of stenosis, visual enhancement score, geometric mean (GM), and the 90th percentile (90P) value from the histogram analysis were significantly higher in PAD than in SAD (p = 0.006 for stenosis, < 0.001 for others). The receiver operating characteristic curve area of GM and 90P were 1 (95% confidence interval [CI], 0.86–1.00). CONCLUSION: A histogram analysis of a relevant arterial wall enhancement allows differentiation between PAD and SAD in patients with acute stroke within the MCA territory.


Subject(s)
Humans , Arteries , Constriction, Pathologic , Magnetic Resonance Imaging , Middle Cerebral Artery , Parents , ROC Curve , Stroke , Tertiary Care Centers
19.
Korean Journal of Dermatology ; : 65-67, 2017.
Article in English | WPRIM | ID: wpr-27290

ABSTRACT

Granuloma annulare is a relatively common benign dermatosis of unknown etiology. It is typically characterized by skin-colored to violaceous annular or arcuate lesions. The localized form of the disease usually resolves spontaneously, but treatment may be required in cases of intractable symptoms such as pruritus, or for cosmetic purposes. Herein, we report the case of a 65-year-old man diagnosed with a localized form of granuloma annulare that was refractory to various treatments but showed clinical improvement with a combined regimen of excimer laser and topical tacrolimus.


Subject(s)
Aged , Humans , Granuloma Annulare , Granuloma , Lasers, Excimer , Pruritus , Skin Diseases , Tacrolimus
20.
Journal of Audiology & Otology ; : 103-106, 2017.
Article in English | WPRIM | ID: wpr-121282

ABSTRACT

BACKGROUND AND OBJECTIVES: A free-beam-type CO₂ laser, which use a micromanipulator mounted on a microscope as the delivery system, has the merit of not being affected by hand tremor at the time of shooting. However, this delivery system has several disadvantages, including a restricted operation range and a risk of incorrect focusing. A fiber-type CO₂ laser uses a hand-held delivery system and has the opposite merits and demerits. We compared the results of stapes surgery with free-beam and fiber type delivery systems. SUBJECTS AND METHODS: The study enrolled 36 patients who underwent stapedotomy with free-beam- (n=26) or fiber- (n=10) type CO₂ lasers. The air-bone (AB) gap closure, bone conduction (BC) change, and operating time were evaluated. The AB gap closure was calculated by subtracting the preoperative BC thresholds from the postoperative air conduction thresholds. The BC change was calculated by subtracting the postoperative BC thresholds from the preoperative BC thresholds. RESULTS: The mean operating time was significantly (p=0.035) shorter in the fiber-type group (72.5±8.2 min) than in the free-beam-type group (80.5±11.4 min). The mean AB gap closure did not differ significantly (p=0.297) between the free-beamand fiber-type groups (5.8±10.1 and 1.4±6.8 dB, respectively). The mean BC change did not differ significantly (p=0.873) between the free-beam- and fiber-type groups (2.4±6.9 and 2.8±5.3 dB, respectively). The hearing outcomes did not differ significantly between the two groups. CONCLUSIONS: Operating times were significantly shorter using the fiber-type CO₂ laser, while hearing outcomes did not differ significantly between the two groups.


Subject(s)
Humans , Bone Conduction , Hand , Hearing , Otosclerosis , Stapes Surgery , Stapes , Tremor
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