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1.
Article in English | WPRIM | ID: wpr-918229

ABSTRACT

Objective@#This study aimed to explore the myelin volume change in patients with mild traumatic brain injury (mTBI) with post-concussion syndrome (PCS) using a multidynamic multiecho (MDME) sequence and automatic whole-brain segmentation. @*Materials and Methods@#Forty-one consecutive mTBI patients with PCS and 29 controls, who had undergone MRI including the MDME sequence between October 2016 and April 2018, were included. Myelin volume fraction (MVF) maps were derived from the MDME sequence. After three dimensional T1-based brain segmentation, the average MVF was analyzed at the bilateral cerebral white matter (WM), bilateral cerebral gray matter (GM), corpus callosum, and brainstem. The Mann–Whitney U-test was performed to compare MVF and myelin volume between patients with mTBI and controls. Myelin volume was correlated with neuropsychological test scores using the Spearman rank correlation test. @*Results@#The average MVF at the bilateral cerebral WM was lower in mTBI patients with PCS (median [interquartile range], 25.2% [22.6%–26.4%]) than that in controls (26.8% [25.6%–27.8%]) (p = 0.004). The region-of-interest myelin volume was lower in mTBI patients with PCS than that in controls at the corpus callosum (1.87 cm3 [1.70–2.05 cm3 ] vs. 2.21 cm3 [1.86– 3.46 cm3 ]; p = 0.003) and brainstem (9.98 cm3 [9.45–11.00 cm3 ] vs. 11.05 cm3 [10.10–11.53 cm3 ]; p = 0.015). The total myelin volume was lower in mTBI patients with PCS than that in controls at the corpus callosum (0.45 cm3 [0.39–0.48 cm3 ] vs. 0.48 cm3 [0.45–0.54 cm3 ]; p = 0.004) and brainstem (1.45 cm3 [1.28–1.59 cm3 ] vs. 1.54 cm3 [1.42–1.67 cm3 ]; p = 0.042). No significant correlation was observed between myelin volume parameters and neuropsychological test scores, except for the total myelin volume at the bilateral cerebral WM and verbal learning test (delayed recall) (r = 0.425; p = 0.048). @*Conclusion@#MVF quantified from the MDME sequence was decreased at the bilateral cerebral WM in mTBI patients with PCS. The total myelin volumes at the corpus callosum and brainstem were decreased in mTBI patients with PCS due to atrophic changes.

2.
Article in English | WPRIM | ID: wpr-918219

ABSTRACT

Objective@#To compare core needle biopsy (CNB) and repeat fine-needle aspiration (rFNA) to reduce the rate of diagnostic surgery and prevent unnecessary surgery in nodules initially diagnosed as atypia/follicular lesions of undetermined significance (AUS/FLUS). @*Materials and Methods@#This study included 231 consecutive patients (150 female and 81 male; mean age ± standard deviation, 51.9 ± 11.7 years) with 235 thyroid nodules (≥ 1 cm) initially diagnosed as AUS/FLUS, who later underwent both rFNA and CNB. The nodules that required diagnostic surgery after the biopsy were defined using three different scenarios according to the rFNA and CNB results: criterion 1, surgery for low-risk indeterminate (categories I and III); criterion 2, surgery for high-risk indeterminate (categories IV and V); and criterion 3, surgery for all indeterminate nodules (categories I, III, IV, and V). We compared the expected rates of diagnostic surgery between CNB and rFNA in all 235 nodules using the three surgical criteria. In addition, the expected rates of unnecessary surgery (i.e., surgery for benign pathology) were compared in a subgroup of 182 nodules with available final diagnoses. @*Results@#CNB showed significantly lower rates of nondiagnostic, AUS/FLUS, and suspicious for malignancy diagnoses (p ≤ 0.016) and higher rates of follicular neoplasm or suspicious for a follicular neoplasm (p < 0.001) and malignant diagnoses (p = 0.031). CNB showed a significantly lower expected rate of diagnostic surgery than rFNA for criterion 1 (29.8% vs. 48.1%, p < 0.001) and criterion 3 (46.4% vs. 55.3%, p = 0.029), and a significantly higher rate for criterion 2 (16.6% vs. 7.2%, p = 0.001). CNB showed a significantly lower expected rate of unnecessary surgery than rFNA for criterion 1 (18.7% vs. 29.7%, p = 0.024). @*Conclusion@#CNB was superior to rFNA in reducing the rates of potential diagnostic surgery and unnecessary surgery for nodules initially diagnosed as AUS/FLUS in a scenario where nodules with low-risk indeterminate results (categories I and III) would undergo surgery.

3.
Korean Journal of Radiology ; : 2094-2123, 2021.
Article in English | WPRIM | ID: wpr-918179

ABSTRACT

Incidental thyroid nodules are commonly detected on ultrasonography (US). This has contributed to the rapidly rising incidence of low-risk papillary thyroid carcinoma over the last 20 years. The appropriate diagnosis and management of these patients is based on the risk factors related to the patients as well as the thyroid nodules. The Korean Society of Thyroid Radiology (KSThR) published consensus recommendations for US-based management of thyroid nodules in 2011 and revised them in 2016. These guidelines have been used as the standard guidelines in Korea. However, recent advances in the diagnosis and management of thyroid nodules have necessitated the revision of the original recommendations. The task force of the KSThR has revised the Korean Thyroid Imaging Reporting and Data System and recommendations for US lexicon, biopsy criteria, US criteria of extrathyroidal extension, optimal thyroid computed tomography protocol, and US follow-up of thyroid nodules before and after biopsy. The biopsy criteria were revised to reduce unnecessary biopsies for benign nodules while maintaining an appropriate sensitivity for the detection of malignant tumors in small (1–2 cm) thyroid nodules. The goal of these recommendations is to provide the optimal scientific evidence and expert opinion consensus regarding US-based diagnosis and management of thyroid nodules.

4.
Article in Korean | WPRIM | ID: wpr-917690

ABSTRACT

Liposarcoma is a very rare malignant tumor affecting the head and neck area. Since it is an invasive and life-threatening disease, active treatments is necessary. However, differential it from lipoma, its corresponding benign counterpart, may be difficult. Herein, we report a rare case of posterior neck myxoid liposarcoma in a 72-year-old man who was initially misdiagnosed with lipoma, including a literature review of differential diagnosis between lipoma and liposarcoma.

5.
Article in English | WPRIM | ID: wpr-915323

ABSTRACT

Purpose@#Frostbite is a hazard to people exposed to cold environments. With the progression of modern industrial development and change of leisure behavior encountering cold environments, frequent accidental exposure to frostbite injury during work and human behavior is increasing, and the predisposing factors of frostbite were greatly changed than before. The purpose of this study was to make epidemiological analysis, and to review the treatment outcomes of frostbite. @*Methods@#From March 2010 to February 2021, this study has included 27 patients with second- to third-degree frostbite injuries in Advanced Burn Reconstruction Center, Bundang Jesaeng Hosptial. A retrospective study was made about the distribution of age, gender, predisposing factors, prevalent area, type of managements, and the length of treatment period. @*Results@#In our institution, acute management of frostbite patients has included rewarming, anticoagulation therapy (acetylsalicylic acid), and agents to improve vascular perfusion (lipo-prostaglandin E1 [Eglandin Ⓡ ]). The 25 frostbite patients with second-degree frostbite (92.6%) were successfully managed by the conservative treatment alone with a mean of 20.3 days healing time. Two patients with third-degree frostbite (7.4%) also showed good outcomes after surgical reconstruction with a mean of 59 days healing time. In our clinical experiences of third-degree frostbite, definitive surgical reconstruction should be recommended to wait for more than 4∼6 weeks for identification of clear demarcation of necrotic tissue caused by frostbite. In this study, 43 frostbite injuries site in 27 frostbite patients occurred. Among them, 15 patients (55.6%) had multiple-site frostbite injury. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments (40.8%), misapplying ice pack for treatment purposes (7.4%), barefoot walking on the cold ground (3.7%), and loss of consciousness in cold grounds (3.7%). The most prevalent sites of frostbite injuries revealed as the hand (58.1%), followed by the foot (32.6%), face (7.0%), and abdomen (2.3%). And in the winter season from the November to March, the incidence rate of frostbite injuries was high at 74.1%. @*Conclusion@#This study included 27 frostbite patients with 43 frostbite sites since last decade in a single institution at the com -munity hospital. The frostbite patients with second-degree frostbite (92.6%) were successfully healed by the conservative treatment alone with a mean of 20.3 days healing time. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments, etc. The most prevalent site of frostbite injuries was the hand (58.1%). And the most prevalent seasonal incidence of frostbite was from November to March (74.1%).

6.
Article in Korean | WPRIM | ID: wpr-903071

ABSTRACT

Purpose@#We aimed to identify the factors associated with the repeated febrile seizures (RFS), defined as recurrent seizures during the same febrile illness. @*Methods@#We reviewed the medical records of children with febrile seizure who visited 4 academic emergency departments from October 2016 through September 2018. Differences were identified in variables regarding clinical and laboratory characteristics between the children with and without RFS. The RFS was the primary outcome. Logistic regression was conducted to identify factors associated with the occurrence of RFS. @*Results@#Among 1,551 children, 922 were included in the study, of whom, 198 (21.5%) underwent RFS. Of the children with RFS, 188 (94.9%) underwent the recurrences within the initial 24 hours. Logistic regression showed focal seizure (adjusted odds ratio, 6.67; 95% confidence interval, 2.37-18.82), venous pH 30 minutes (1.90; 1.30-2.78) as the factors for RFS. @*Conclusion@#In children with febrile seizure, focal seizure, acidosis, and prolonged postictal state may be independent risk factors for RFS. These findings may be informed to healthcare professionals and parents caring for children with febrile seizure.

7.
Article in English | WPRIM | ID: wpr-914752

ABSTRACT

Cranial-nerve disorders can be caused by a wide spectrum of diseases, including congenital, inflammatory, and tumorous diseases, and are often encountered in practice. However, the imaging of cranial-nerve disorders is challenging, and understanding the anatomical differences of each region is essential for conducting the best protocols and for detecting subtle changes in cranial nerves during magnetic resonance imaging (MRI) examinations. In this review we discuss which MRI techniques are best for observing normal and pathologic appearance, according to the different regions of the cranial nerves.

8.
Gut and Liver ; : 895-903, 2021.
Article in English | WPRIM | ID: wpr-914355

ABSTRACT

Background/Aims@#Glecaprevir/pibrentasvir (G/P) is the first pan-genotypic direct-acting antiviral combination therapy approved in Korea. An integrated analysis of five phase II and III trials was conducted to evaluate the efficacy and safety of G/P in Korean patients with chronic hepatitis C virus (HCV) infection. @*Methods@#The study analyzed pooled data on Korean patients with HCV infection enrolled in the ENDURANCE 1 and 2, SURVEYOR II part 4 and VOYAGE I and II trials, which evaluated the efficacy and safety of 8 or 12 weeks of G/P treatment. The patients were either treatment-naïve or had received sofosbuvir or interferon-based treatment. Efficacy was evaluated by assessing the rate of sustained virologic response at 12 weeks posttreatment (SVR12). Safety was evaluated by monitoring adverse events (AEs) and laboratory assessments. @*Results@#The analysis included 265 patients; 179 (67.5%) were HCV treatment-naïve, and most patients were either subgenotype 1B (48.7%) or 2A (44.5%). In the intention-to-treat population, 262 patients (98.9%) achieved SVR12. Three patients did not achieve SVR12: one had virologic failure and two had non-virologic failures. Most AEs were grade 1/2; eight patients (3.0%) expe-rienced at least one grade ≥3 AE. No serious AEs related to G/P treatment were reported, and grade ≥3 hepatic laboratory abnormalities were rare (0.8%). @*Conclusions@#G/P therapy was highly efficacious and well tolerated in Korean patients with HCV infection, with most patients achieving SVR12. The safety profile was comparable to that observed in a pooled analysis of a global pan-genotypic population of patients with HCV infection who received G/P.

9.
Cancer Research and Treatment ; : 1004-1014, 2021.
Article in English | WPRIM | ID: wpr-913806

ABSTRACT

Purpose@#The incidence of human papillomavirus (HPV)-related oropharyngeal cancer (OPC) has increased, and staging and optimal therapeutic approaches are challenging. A questionnaire survey was conducted to investigate the controversial treatment policy of stage T2 OPC according to the N category and determine the opinions of multidisciplinary experts in Korea. @*Materials and Methods@#Five OPC scenarios were developed by the Subcommittee on Oropharyngeal Treatment Guidelines of the Korean Society for Head and Neck Oncology and distributed to experts of multidisciplinary treatment hospitals. @*Results@#Sixty-five experts from 45 institutions responded. For the HPV-positive T2N0M0 scenario, 67.7% of respondents selected surgery followed by definitive concurrent chemoradiotherapy (CCRT) or radiotherapy alone. For the T2N1M0 HPV-positive scenario, there was a notable difference in the selection of primary treatment by expert specialty; 53.9% of respondents selected surgery and 39.8% selected definitive CCRT as the primary treatment. For the T2N3M0 advanced HPV-positive scenario, 50.0% of respondents selected CCRT and 33.3% considered induction chemotherapy (IC) as the primary treatment. CCRT and IC were significantly more frequently selected for the HPV-related OPC cases (p=0.010). The interdepartmental variability showed that the head and neck surgeons and medical oncologists favored surgery, whereas the radiation oncologists preferably selected definitive CCRT (p < 0.001). @*Conclusion@#In this study, surgery was preferred for lymph node-negative OPC, and as lymph node metastasis progressed, CCRT tended to be preferred, and IC was administered. Clinical practice patterns by stage and HPV status showed differences according to expert specialty. Multidisciplinary consensus guidelines will be essential in the future.

10.
Article in English | WPRIM | ID: wpr-913514

ABSTRACT

Purpose@#Splenic flexure colon cancer (SFCC) is a rare disease that accounts for 2%–8% of colorectal cancers, and the extent of surgery and resection is still debatable. There have also been few studies on the safety and feasibility of laparoscopic surgery for SFCC. The purpose of this study is to evaluate outcomes and prognoses of surgery for SFCC. @*Methods@#We included patients with stage 1 to 3 who had undergone laparoscopic surgery for distal transverse-to-sigmoid colon cancer at 2 hospitals from March 2004 to December 2016 and collected data by retrospective design. We defined SFCC as being cancer between distal transverse and proximal descending colon. The short- and long-term outcomes of the anterior resection (AR) group (those patients who had undergone laparoscopic AR for mid and distal descending to sigmoid colon cancer) and the left colon resection (LR) group (those who had undergone laparoscopic segmental left colectomy for SFCC) were compared using propensity score matching. @*Results@#The median follow-up period was 60 months. The numbers of subjects in the AR and the LR groups were 948 and 118. After 2:1 propensity score matching, 236 vs. 118 patients were selected. There was no significant difference in 5-year disease-free survival (80.7% vs. 78.6%, P = 0.607), and both the 5-year overall survival (89.2% vs. 88.2%, P = 0.563) as well as short-term outcomes showed no statistical difference in most of the variables. @*Conclusion@#Laparoscopic segmental left colectomy can be one option among the standard procedures for SFCC.

11.
Korean Journal of Radiology ; : 1579-1586, 2021.
Article in English | WPRIM | ID: wpr-902504

ABSTRACT

Objective@#To evaluate the diagnostic performance of the modified Korean Thyroid Imaging Reporting and Data System (K-TIRADS), and compare it with the 2016 version of K-TIRADS using the Thyroid Imaging Network of Korea. @*Materials and Methods@#Between June and September 2015, 5708 thyroid nodules (≥ 1.0 cm) from 5081 consecutive patients who had undergone thyroid ultrasonography at 26 institutions were retrospectively evaluated. We used a biopsy size threshold of 2 cm for K-TIRADS 3 and 1 cm for K-TIRADS 4 (modified K-TIRADS 1) or 1.5 cm for K-TIRADS 4 (modified K-TIRADS 3). The modified K-TIRADS 2 subcategorized the K-TIRADS 4 into 4A and 4B, and the cutoff sizes for the biopsies were defined as 1 cm for K-TIRADS 4B and 1.5 cm for K-TIRADS 4A. The diagnostic performance and the rate of unnecessary biopsies of the modified K-TIRADS for detecting malignancy were compared with those of the 2016 K-TIRAD, which were stratified by nodule size (with a threshold of 2 cm). @*Results@#A total of 1111 malignant nodules and 4597 benign nodules were included. The sensitivity, specificity, and unnecessary biopsy rate of the benign nodules were 94.9%, 24.4%, and 60.9% for the 2016 K-TIRADS; 91.0%, 39.7%, and 48.6% for the modified K-TIRADS 1; 84.9%, 45.9%, and 43.5% for the modified K-TIRADS 2; and 76.1%, 50.2%, and 40.1% for the modified K-TIRADS 3. For small nodules (1–2 cm), the diagnostic sensitivity of the modified K-TIRADS decreased by 5.2–25.6% and the rate of unnecessary biopsies reduced by 19.2–32.8% compared with those of the 2016 K-TIRADS (p 2 cm), the modified K-TIRADSs maintained a very high sensitivity for detecting malignancy (98%). @*Conclusion@#The modified K-TIRADSs significantly reduced the rate of unnecessary biopsies for small (1–2 cm) nodules while maintaining a very high sensitivity for malignancy for large (> 2 cm) nodules.

12.
Korean Journal of Radiology ; : 1514-1524, 2021.
Article in English | WPRIM | ID: wpr-902499

ABSTRACT

Objective@#To develop a radiomics risk score based on dynamic contrast-enhanced (DCE) MRI for prognosis prediction in patients with glioblastoma. @*Materials and Methods@#One hundred and fifty patients (92 male [61.3%]; mean age ± standard deviation, 60.5 ± 13.5 years) with glioblastoma who underwent preoperative MRI were enrolled in the study. Six hundred and forty-two radiomic features were extracted from volume transfer constant (Ktrans), fractional volume of vascular plasma space (Vp), and fractional volume of extravascular extracellular space (Ve) maps of DCE MRI, wherein the regions of interest were based on both T1-weighted contrast-enhancing areas and non-enhancing T2 hyperintense areas. Using feature selection algorithms, salient radiomic features were selected from the 642 features. Next, a radiomics risk score was developed using a weighted combination of the selected features in the discovery set (n = 105); the risk score was validated in the validation set (n = 45) by investigating the difference in prognosis between the “radiomics risk score” groups. Finally, multivariable Cox regression analysis for progression-free survival was performed using the radiomics risk score and clinical variables as covariates. @*Results@#16 radiomic features obtained from non-enhancing T2 hyperintense areas were selected among the 642 features identified. The radiomics risk score was used to stratify high- and low-risk groups in both the discovery and validation sets (both p < 0.001 by the log-rank test). The radiomics risk score and presence of isocitrate dehydrogenase (IDH) mutation showed independent associations with progression-free survival in opposite directions (hazard ratio, 3.56; p = 0.004 and hazard ratio, 0.34; p = 0.022, respectively). @*Conclusion@#We developed and validated the “radiomics risk score” from the features of DCE MRI based on non-enhancing T2 hyperintense areas for risk stratification of patients with glioblastoma. It was associated with progression-free survival independently of IDH mutation status.

13.
Article in English | WPRIM | ID: wpr-902467

ABSTRACT

Imaging plays a key role in the diagnosis and characterization of thyroid diseases, and the information provided by imaging studies is essential for management planning. A referral guideline for imaging studies may help physicians make reasonable decisions and minimize the number of unnecessary examinations. The Korean Society of Thyroid Radiology (KSThR) developed imaging guidelines for thyroid nodules and differentiated thyroid cancer using an adaptation process through a collaboration between the National Evidence-based Healthcare Collaborating Agency and the working group of KSThR, which is composed of radiologists specializing in thyroid imaging. When evidence is either insufficient or equivocal, expert opinion may supplement the available evidence for recommending imaging. Therefore, we suggest rating the appropriateness of imaging for specific clinical situations in this guideline.

14.
Korean Journal of Radiology ; : 1352-1368, 2021.
Article in English | WPRIM | ID: wpr-902424

ABSTRACT

Objective@#For an accurate dynamic contrast-enhanced (DCE) MRI analysis, exact baseline T1 mapping is critical. The purpose of this study was to compare the pharmacokinetic parameters of DCE MRI using synthetic MRI with those using fixed baseline T1 values. @*Materials and Methods@#This retrospective study included 102 patients who underwent both DCE and synthetic brain MRI. Two methods were set for the baseline T1: one using the fixed value and the other using the T1 map from synthetic MRI. The volume transfer constant (Ktrans ), volume of the vascular plasma space (vp), and the volume of the extravascular extracellular space (ve) were compared between the two methods. The interclass correlation coefficients and the Bland-Altman method were used to assess the reliability. @*Results@#In normal-appearing frontal white matter (WM), the mean values of Ktrans , ve, and vp were significantly higher in the fixed value method than in the T1 map method. In the normal-appearing occipital WM, the mean values of ve and vp were significantly higher in the fixed value method. In the putamen and head of the caudate nucleus, the mean values of Ktrans , ve, and vp were significantly lower in the fixed value method. In addition, the T1 map method showed comparable interobserver agreements with the fixed baseline T1 value method. @*Conclusion@#The T1 map method using synthetic MRI may be useful for reflecting individual differences and reliable measurements in clinical applications of DCE MRI.

15.
Korean Journal of Radiology ; : 1369-1378, 2021.
Article in English | WPRIM | ID: wpr-902423

ABSTRACT

Objective@#Few attempts have been made to investigate the prognostic value of dynamic contrast-enhanced (DCE) MRI or dynamic susceptibility contrast (DSC) MRI of non-enhancing, T2-high-signal-intensity (T2-HSI) lesions of glioblastoma multiforme (GBM) in newly diagnosed patients. This study aimed to investigate the prognostic values of DCE MRI and DSC MRI parameters from non-enhancing, T2-HSI lesions of GBM. @*Materials and Methods@#A total of 76 patients with GBM who underwent preoperative DCE MRI and DSC MRI and standard treatment were retrospectively included. Six months after surgery, the patients were categorized into early progression (n = 15) and non-early progression (n = 61) groups. We extracted and analyzed the permeability and perfusion parameters of both modalities for the non-enhancing, T2-HSI lesions of the tumors. The optimal percentiles of the respective parameters obtained from cumulative histograms were determined using receiver operating characteristic (ROC) curve and univariable Cox regression analyses. The results were compared using multivariable Cox proportional hazards regression analysis of progression-free survival. @*Results@#The 95th percentile value (PV) of Ktrans, mean Ktrans, and median Ve were significant predictors of early progression as identified by the ROC curve analysis (area under the ROC curve [AUC] = 0.704, p = 0.005; AUC = 0.684, p = 0.021; and AUC = 0.670, p = 0.0325, respectively). Univariable Cox regression analysis of the above three parametric values showed that the 95th PV of Ktrans and the mean Ktrans were significant predictors of early progression (hazard ratio [HR] = 1.06, p = 0.009; HR = 1.25, p = 0.017, respectively). Multivariable Cox regression analysis, which also incorporated clinical parameters, revealed that the 95th PV of Ktrans was the sole significant independent predictor of early progression (HR = 1.062, p < 0.009). @*Conclusion@#The 95th PV of Ktrans from the non-enhancing, T2-HSI lesions of GBM is a potential prognostic marker for disease progression.

16.
Korean Journal of Radiology ; : 1323-1331, 2021.
Article in English | WPRIM | ID: wpr-902418

ABSTRACT

Objective@#To identify the association between renal tumor complexity and pathologic renal sinus invasion (RSI) and evaluate the usefulness of computed tomography tumor features for predicting RSI in patients with renal cell carcinoma (RCC). @*Materials and Methods@#This retrospective study included 276 consecutive patients who underwent radical nephrectomy for RCC with a size of ≤ 7 cm between January 2014 and October 2017. Tumor complexity and anatomical renal sinus involvement were evaluated using two standardized scoring systems: the radius (R), exophytic or endophytic (E), nearness to collecting system or sinus (N), anterior or posterior (A), and location relative to polar lines (RENAL) nephrometry and preoperative aspects and dimensions used for anatomical classification (PADUA) system. CT-based tumor features, including shape, enhancement pattern, margin at the interface of the renal sinus (smooth vs. non-smooth), and finger-like projection of the mass, were also assessed by two independent radiologists. Univariable and multivariable logistic regression analyses were performed to identify significant predictors of RSI. The positive predictive value, negative predictive value (NPV), accuracy of anatomical renal sinus involvement, and tumor features were evaluated. @*Results@#Eighty-one of 276 patients (29.3%) demonstrated RSI. Among highly complex tumors (RENAL or PADUA score ≥ 10), the frequencies of RSI were 42.4% (39/92) and 38.0% (71/187) using RENAL and PADUA scores, respectively. Multivariable analysis showed that a non-smooth margin and the presence of a finger-like projection were significant predictors of RSI.Anatomical renal sinus involvement showed high NPVs (91.7% and 95.2%) but low accuracy (40.2% and 43.1%) for RSI, whereas the presence of a non-smooth margin or finger-like projection demonstrated comparably high NPVs (90.0% and 91.3% for both readers) and improved accuracy (67.0% and 73.9%, respectively). @*Conclusion@#A non-smooth margin or the presence of a finger-like projection can be used as a preoperative CT-based tumor feature for predicting RSI in patients with RCC.

17.
Article in English | WPRIM | ID: wpr-901613

ABSTRACT

Background and Objectives@#Cavotricuspid isthmus (CTI) block is easily achieved, and prophylactic ablation can be performed during atrial fibrillation (AF) ablation. However, the previous study was too small and short-term to clarify the efficacy of this block. @*Methods@#Patients who underwent catheter ablation for paroxysmal AF were enrolled, and patients who had previous or induced atrial flutter (AFL) were excluded. We randomly assigned 366 patients to pulmonary vein isolation (PVI) only and prophylactic CTI ablation (PVI vs. PVI+CTI). @*Results@#There was no significant difference in procedure time between the two groups because most CTI blocks were performed during the waiting time after the PVI (176.8±72.6 minutes in PVI vs. 174.2±76.5 minutes in PVI+CTI, p=0.75). All patients were followed up for at least 18 months, and the median follow-up was 3.4 years. The recurrence rate of AF or AFL was not different in the 2 groups (25.7% in PVI vs. 25.7% in PVI+CTI, p=0.92). The recurrence rate of any AFL was not significantly different in the 2 groups (3.3% in PVI vs. 1.6% in PVI+CTI, p=0.31). The recurrence rate of typical AFL also was not different (0.5% in PVI vs. 0.5% in PVI+CTI, p=0.99). @*Conclusions@#In this large and long-term follow-up study, prophylactic CTI ablation had no benefit in patients with paroxysmal AF without typical AFL.

18.
Article in English | WPRIM | ID: wpr-901366

ABSTRACT

Purpose@#To explore cerebrovascular reservoir (CVR) and arterial transit time (ATT) changes using acetazolamide-challenged multi-phase arterial spin labeling (MP-ASL) perfusion-weighted MRI in chronic cerebrovascular steno-occlusive disease. @*Materials and Methods@#This retrospective study enrolled patients with chronic steno-occlusion who underwent acetazolamide-challenged MP-ASL between June 2019 and October 2020.Cerebral blood flow, CVR, basal ATT, and ATT changes associated with severe stenosis, total occlusion, and chronic infarction lesions were compared. @*Results@#There were 32 patients (5 with bilateral steno-occlusion) in our study sample. The CVR was significantly reduced during total occlusion compared with severe stenosis (26.2% ± 28.8% vs. 41.4% ± 34.1%, respectively, p = 0.004). The ATT changes were not significantly different (p = 0.717). The CVR was marginally lower in patients with chronic infarction (29.6% ± 39.1% vs. 38.9% ± 28.7%, respectively, p = 0.076). However, the ATT was less shortened in pa-tients with chronic infarction (-54 ± 135 vs. -117 ± 128 ms, respectively, p = 0.013). @*Conclusion@#Acetazolamide-challenged MP-ASL provides an MRI-based CVR evaluation tool for chronic steno-occlusive disease.

19.
Article in English | WPRIM | ID: wpr-900344

ABSTRACT

Purpose@#The prognostic factors in obstructive colon cancer have not been clearly identified. We aimed to identify the prognostic factor to establish optimal treatment strategy in obstructive colon cancer. @*Methods@#Patients who underwent surgery for primary colon cancer in stages II and III with symptomatic obstruction from 2004 to 2010 in six hospitals were retrospectively collected. Clinicopathological and surgical outcomes were compared between stent insertion and emergent surgery group. Multiple regression analysis and survival curve analysis were used to identif y the prognostic factors in symptomatic obstructive colon cancer. @*Results@#Among 210 patients, 168 patients (80.0%) underwent stent insertion followed by surgery and 42 patients (20.0%) underwent emergent surgery. Laparoscopic approach (55.4% vs. 23.8%, p< 0.001) and adequate lymph node (LN) harvest (≥12) (93.5% vs. 69.0%, p < 0.001) were significantly higher in stent insertion group. In multiple regression analysis, emergent surgery (hazard ratio [HR], 2.153; 95% confidence interval [CI], 1.031–4.495), vascular invasion (HR, 6.257; 95% CI, 2.784–14.061), and omitting adjuvant chemotherapy (HR, 3.107; 95% CI, 1.394–6.925) were independent poor prognostic factors in 5-year overall survival, and N stage (N1: HR, 3.095; 95% CI, 1.316–7.284; N2: HR, 4.156; 95% CI, 1.671–10.333) was the only poor prognostic factor in 5-year disease-free survival. @*Conclusion@#In symptomatic obstructive colon cancer, emergent surgery, N stage, vascular invasion, and omission of adjuvant chemotherapy were independent poor prognostic factors. Stent insertion is suggested as the initial treatment for symptomatic obstructive colon cancer, and adjuvant chemotherapy is recommended, especially when vascular invasion or LN metastasis is confirmed.

20.
Article in English | WPRIM | ID: wpr-898858

ABSTRACT

Purpose@#Mild cognitive impairment (MCI) is a prodromal stage of Alzheimer's disease (AD). Brain atrophy in this disease spectrum begins in the medial temporal lobe structure, which can be recognized by magnetic resonance imaging. To overcome the unsatisfactory inter-observer reliability of visual evaluation, quantitative brain volumetry has been developed and widely investigated for the diagnosis of MCI and AD. The aim of this study was to assess the prediction accuracy of quantitative brain volumetry using a fully automated segmentation software package, NeuroQuant®, for the diagnosis of MCI. @*Materials and Methods@#A total of 418 subjects from the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer’s Disease cohort were included in our study. Each participant was allocated to either a cognitively normal old group (n = 285) or an MCI group (n = 133). Brain volumetric data were obtained from T1-weighted images using the NeuroQuant software package. Logistic regression and receiver operating characteristic (ROC) curve analyses were performed to investigate relevant brain regions and their prediction accuracies. @*Results@#Multivariate logistic regression analysis revealed that normative percentiles of the hippocampus (P < 0.001), amygdala (P = 0.003), frontal lobe (P = 0.049), medial parietal lobe (P = 0.023), and third ventricle (P = 0.012) were independent predictive factors for MCI. In ROC analysis, normative percentiles of the hippocampus and amygdala showed fair accuracies in the diagnosis of MCI (area under the curve: 0.739 and 0.727, respectively). @*Conclusion@#Normative percentiles of the hippocampus and amygdala provided by the fully automated segmentation software could be used for screening MCI with a reasonable post-processing time. This information might help us interpret structural MRI in patients with cognitive impairment.

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