The diagnostic ability of an additional midline peripheral zone biopsy in transrectal ultrasonography-guided 12-core prostate biopsy to detect midline prostate cancer

황인평,김상윤,조정연,이명석,김승협 대한초음파의학회 2016 ULTRASONOGRAPHY Vol.35 No.1

Purpose: The goal of this study was to evaluate the diagnostic effect of adding a midline peripheral zone (PZ) biopsy to the 12-core biopsy protocol used to diagnose prostate cancer (PC), and to assess the clinical and pathologic characteristics of midline-positive PC in order to identify a potential subgroup of patients who would require midline PZ biopsy. Methods: This study included 741 consecutive patients who underwent a transrectal ultrasonography-guided, 12-core prostate biopsy with an additional midline core biopsy between October 2012 and December 2013. We grouped patients by the presence or absence of PC and subdivided patients with PC based on the involvement of the midline core. The clinical characteristics of these groups were compared, including serum prostate-specific antigen (PSA) concentrations, PSA density, and pathological features in the biopsy specimens. Results: PC was detected in 289 patients (39.0%). Among the PC patients, 66 patients (22.8%) had midline PC. No patients were diagnosed with PC based only on a midline core. The Gleason scores, number of positive cores, tumor core length, serum PSA concentrations, and PSA density were significantly higher in patients with midline-positive PC (P<0.001). Furthermore, significant cancer was more frequent in the midline-positive group (98.5% vs. 78.0%). Conclusion: Patients showing a positive result for PC in a midline PZ biopsy were more likely to have multiple tumors or large-volume PC with a high tumor burden. However, our data indicated that an additional midline core biopsy is unlikely to be helpful in detecting occult midline PC.

Cerebrovascular Reservoir and Arterial Transit Time Changes Assessed by Acetazolamide-Challenged Multi-Phase Arterial Spin Labeling Perfusion MRI in Chronic Cerebrovascular Steno-Occlusive Disease

황인평,손철호,정근화,연응구,이지예,유노을,강경미,윤태진,최승홍,김지훈 대한영상의학회 2021 대한영상의학회지 Vol.82 No.3

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 patients 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.

Portable high-intensity focused ultrasound system with 3D electronic steering, real-time cavitation monitoring, and 3D image reconstruction algorithms: a preclinical study in pigs

최진우,이재영,황의진,황인평,우성민,이창주,박은주,최병인 대한초음파의학회 2014 ULTRASONOGRAPHY Vol.33 No.3

Purpose: The aim of this study was to evaluate the safety and accuracy of a new portableultrasonography-guided high-intensity focused ultrasound (USg-HIFU) system with a3-dimensional (3D) electronic steering transducer, a simultaneous ablation and imaging module,real-time cavitation monitoring, and 3D image reconstruction algorithms. Methods: To address the accuracy of the transducer, hydrophones in a water chamber wereused to assess the generation of sonic fields. An animal study was also performed in five pigsby ablating in vivo thighs by single-point sonication (n=10) or volume sonication (n=10) andex vivo kidneys by single-point sonication (n=10). Histological and statistical analyses wereperformed. Results: In the hydrophone study, peak voltages were detected within 1.0 mm from the targetson the y- and z-axes and within 2.0-mm intervals along the x-axis (z-axis, direction of ultrasoundpropagation; y- and x-axes, perpendicular to the direction of ultrasound propagation). Twentynineof 30 HIFU sessions successfully created ablations at the target. The in vivo porcine thighstudy showed only a small discrepancy (width, 0.5-1.1 mm; length, 3.0 mm) between theplanning ultrasonograms and the pathological specimens. Inordinate thermal damage wasnot observed in the adjacent tissues or sonic pathways in the in vivo thigh and ex vivo kidneystudies. Conclusion: Our study suggests that this new USg-HIFU system may be a safe and accuratetechnique for ablating soft tissues and encapsulated organs.

Monopolar Radiofrequency Ablation Using a Dual-Switching System and a Separable Clustered Electrode: Evaluation of the In Vivo Efficiency

윤정희,이정민,황의진,황인평,백지현,한준구,최병인 대한영상의학회 2014 Korean Journal of Radiology Vol.15 No.2

Objective: To determine the in vivo efficiency of monopolar radiofrequency ablation (RFA) using a dual-switching (DS) system and a separable clustered (SC) electrode to create coagulation in swine liver. Materials and Methods: Thirty-three ablation zones were created in nine pigs using a DS system and an SC electrode in the switching monopolar mode. The pigs were divided into two groups for two experiments: 1) preliminary experiments (n = 3) to identify the optimal inter-electrode distances (IEDs) for dual-switching monopolar (DSM)-RFA, and 2) main experiments (n = 6) to compare the in vivo efficiency of DSM-RFA with that of a single-switching monopolar (SSM)-RFA. RF energy was alternatively applied to one of the three electrodes (SSM-RFA) or concurrently applied to a pair of electrodes (DSM-RFA) for 12 minutes in in vivo porcine livers. The delivered RFA energy and the shapes and dimensions of the coagulation areas were compared between the two groups. Results: No pig died during RFA. The ideal IEDs for creating round or oval coagulation area using the DSM-RFA were 2.0 and 2.5 cm. DSM-RFA allowed more efficient RF energy delivery than SSM-RFA at the given time (23.0 ± 4.0 kcal vs. 16.92 ± 2.0 kcal, respectively; p = 0.0005). DSM-RFA created a significantly larger coagulation volume than SSM-RFA (40.4 ± 16.4 cm3 vs. 20.8 ± 10.7 cm3; p < 0.001). Both groups showed similar circularity of the ablation zones (p = 0.29). Conclusion: Dual-switching monopolar-radiofrequency ablation using an SC electrode is feasible and can create larger ablation zones than SSM-RFA as it allows more RF energy delivery at a given time.

군용 궤도차량 엔진 제어 요소

송치권(Chikwon Song),황인평(Inpyoung Hwang) 한국자동차공학회 2010 한국자동차공학회 학술대회 및 전시회 Vol.2010 No.11

The engine for military tracked vehicle needs precision control technology to satisfy the engine performance and it mounted restricted space of engine room. Under abnormal condition it need to emergency start, immediate start, severe environment of cold start, 60% gradient mobility, submerge of maneuvering special task to raise the combat capacity. This paper look over control factor of engine for military tracked vehicle and draw out.

Ultrasonographic Indeterminate Lymph Nodes in Preoperative Thyroid Cancer Patients: Malignancy Risk and Ultrasonographic Findings Predictive of Malignancy

Roh-Eul Yoo,김지훈,배정모,황인평,강경미,윤태진,최승홍,손철호,Jung Hyo Rhim,Sun-Won Park 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.5

Objective: Proper management of lymph nodes (LNs) with ultrasonographic (US) indeterminate features in thyroid cancer patients remains elusive. We aimed to evaluate the malignancy risk and US findings predictive of malignancy for US indeterminate LNs in preoperative thyroid cancer patients through node-by-node correlation. Materials and Methods: A total of 348 LNs in 284 thyroid cancer patients, who underwent fine-needle aspiration or coreneedle biopsy between December 2006 and June 2015, were included. We determined the malignancy risks for US probably benign, indeterminate, and suspicious categories. For US indeterminate LNs, which had neither echogenic hilum nor hilar vascularity in the absence of any suspicious finding, US findings were compared between benign and metastatic LNs using Mann-Whitney U test and Fisher’s exact test. Results: US imaging diagnoses were probably benign in 20.7% (n = 72) cases, indeterminate in 23.6% (n = 82), and suspicious in 55.7% (n = 194). Malignancy risk of US indeterminate LNs (19.5% [16/82]) differed from those of the US probably benign (2.8% [2/72]) (p = 0.002) and US suspicious LNs (78.4% [152/194]) (p < 0.001). Among US indeterminate LNs, there were no significant differences in short, long, and long-to-short diameter (L/S) ratios between benign and metastatic LNs (3.9 vs. 3.8 mm, p = 0.619; 7.3 vs. 7.3 mm, p = 0.590; 1.9 vs. 1.9, p = 0.652). Conclusion: US indeterminate LNs were frequently encountered during preoperative evaluation and had intermediate malignancy risk. Given the lack of discriminative power of size criteria and L/S ratio, clinical factors such as surgical strategy and node size should be considered for proper triage of US indeterminate LNs in thyroid cancer.

경동맥 3D TOF 자기공명 혈관조영 영상을 활용한 딥러닝 전인학습 기반 뇌백질변성 부피 예측

장혜정(Hei-Jeung Jang),최규성(Kyu Sung Choi),최승홍(Seung-hong Choi),황인평(Inpyeong Hwang),신태훈(Taehoon Shin) 대한전자공학회 2023 대한전자공학회 학술대회 Vol.2023 No.6

It has been suggested that the association between white matter hyperintensity (WMH) and carotid arterial features includes carotid plaques and carotid intima-media thickness, arterial stiffness, or remodeling. Under the hypothesis that white, matter abnormalities correlate with the configuration of the feeding carotid arteries, we use deep learning to estimate WMH volumes based solely on time-of-flight (TOF) carotid MRA images. To improve performance, we use transfer learning from a pre-trained V-Net for carotid artery segmentation. We evaluate the WMH volume prediction performance by applying Grad-CAM and confirm that our proposed transfer learning model estimates the WMH volume derived from carotid arterial features.

Low-Tube-Voltage CT Urography Using Low-Concentration-Iodine Contrast Media and Iterative Reconstruction: A Multi-Institutional Randomized Controlled Trial for Comparison with Conventional CT Urography

김상윤,Jeong Yeon Cho,이중엽,황성일,문민환,이은주,홍성숙,김찬교,김경아,박성빈,성득제,김용수,You Me Kim,정성일,나성은,김동원,이현,심영섭,황인평,우성민,최혁재 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.6

Objective: To compare the image quality of low-tube-voltage and low-iodine-concentration-contrast-medium (LVLC) computed tomography urography (CTU) with iterative reconstruction (IR) with that of conventional CTU. Materials and Methods: This prospective, multi-institutional, randomized controlled trial was performed at 16 hospitals using CT scanners from various vendors. Patients were randomly assigned to the following groups: 1) the LVLC-CTU (80 kVp and 240 mgI/mL) with IR group and 2) the conventional CTU (120 kVp and 350 mgI/mL) with filtered-back projection group. The overall diagnostic acceptability, sharpness, and noise were assessed. Additionally, the mean attenuation, signalto- noise ratio (SNR), contrast-to-noise ratio (CNR), and figure of merit (FOM) in the urinary tract were evaluated. Results: The study included 299 patients (LVLC-CTU group: 150 patients; conventional CTU group: 149 patients). The LVLCCTU group had a significantly lower effective radiation dose (5.73 ± 4.04 vs. 8.43 ± 4.38 mSv) compared to the conventional CTU group. LVLC-CTU showed at least standard diagnostic acceptability (score ≥ 3), but it was non-inferior when compared to conventional CTU. The mean attenuation value, mean SNR, CNR, and FOM in all pre-defined segments of the urinary tract were significantly higher in the LVLC-CTU group than in the conventional CTU group. Conclusion: The diagnostic acceptability and quantitative image quality of LVLC-CTU with IR are not inferior to those of conventional CTU. Additionally, LVLC-CTU with IR is beneficial because both radiation exposure and total iodine load are reduced.