인플루엔자 바이러스에 의한 소아 하기도 감염의 방사선 소견$^1$

송호택,박충기,최요원,전석철,함창곡,Song, Ho-Taek,Park, Chung-Gi,Choe, Yo-Won,Jeon, Seok-Cheol,Ham, Chang-Gok 대한영상의학회 2002 대한영상의학회지 Vol.47 No.2

목적: 인플루엔자 바이러스는 바이러스성 소아 하기도 감염의 원인 중 RS(Respiratory syn-cytial)바이러스 다음으로 많은 빈도를 차지하는 주요 감염원이다. 저자들은 우리나라에서의 인플루엔자 바이러스에 의한 소아 하기도 감염의 방사선학적 소견을 알아보았다. 대상과 방법: 1997년 3월에서 2000년 4월까지 호흡기 감염 증세로 내원하여 비인두 흡입물을 직접 또는 간접면역형광염색법으로 검사하여 인플루엔자 바이러스가 확인된 환아 중 필름고찰이 가능하였던 105명 (남자 76명, 여자 29명, 평균연령 2.4세)의 단순 흉부 촬영사진을폐문주변 기관지주위 침윤, 과통기, 무기폐, 폐경화, 폐문 임파절 비대를 중심으로 후향적으로 결과: 모든 대상환자 (n=105)중 양측성 폐문주변 기관지주위 침윤이 78.1%(n=82), 과통 기가 63.8%(n=67), 무기폐가 3.8%(n=4,분절성 50%, 엽성 50%), 폐경화가 16.2%[ n=17, 분절성 70.6%(n=12), 엽성 29.4%(n=5)] 에서 있었으며 폐문 임파절 비대는 1예에서 있었고 흉막삼출은 보이지 않았다. 특히 croup의 증상으로 경부 촬영을 한 14명중 성문하 기관지의 협착을 보인 예가 12명에서 있었다. 결론: 인플루엔자 바이러스 호흡기 감염의 주요 방사선학적 소견은 양측성 폐문주변 기관지주 위 침윤과 과통기였다. 일부 환자에서 성문하 기관지 협착을 보여 상기도 감염과 동반되는 양 상을 보였다. 무기폐와 흉막삼출 그리고 폐문 임파절 비대는 없거나 드물었다. Purpose: After the RS (respiratory syncytial) virus, the influenza virus is the most common cause of childhood lower respiratory tract infection. We assessed the radiologic findings of childhood lower respiratory tract infection by the influenza virus. Materials and Methods: A total of 105 pediatric patients (76 males and 29 females; mean age, 2.4 years) with symptoms of respiratory tract infection were examined between March 1997 and April 2000. Nasopharyngeal aspirates were obtained and influenza virus infection was confirmed by direct or indirect immunofluorescent assays. Peribronchial infiltration, hyperinflation, atelectasis, pulmonary consolidation, and hilar lymphadenopathy were evaluated retrospectively at simple chest radiography. Results: Bilateral perihilar peribronchial infiltration was noted in 78.1% of patients (n=82), hyperinflation in 63.8% (n=67), atelectasis in 3.8% (n=4; segmental 50%, lobar 50%), and pulmonary consolidation in 16.2% [n=17; segmental 70.6% (n=12), lobar 29.4% (n=5)]. Hilar lymphadenopathy was noted in one patient in whom there was no pleural effusion, and subglottic airway narrowing in 12 of 14 in whom the croup symptom complex was present. Conclusion: The major radiologic findings of influenza virus infection were bilateral perihilar peribronchial infiltration and hyperinflation. In some patients, upper respiratory tract infection was combined with subgolttic airway narrowing. Atelectasis or pleural effusion was rare.

양성 낭성 종괴의 고주파 열치료: 돼지 담낭을 이용한 실험적 예비 연구

송호택,임현철,최정빈,오재천,조온구,고병희,김용수,서홍석,주경빈 대한영상의학회 2001 대한영상의학회지 Vol.44 No.5

목적 : 고주파 열치료(radiofrequency thermal ablation)가 양성 낭성 종괴에 대한 치료법으로서 이용될 수 있는지 실험적 연구를 통해 알아보고자하였다 대상과 방법: 총15개의 적출된 돼지 담낭에 대하여 50와트 고주파 발생기와 15게이지 바늘형 고주파 전극을 사용하여 실험하였다. 증상이 있는 양성 낭종을 가정한 담낭 벽에 최대한의 응고적 괴사를 만든 후 병변주변 장기를 가정한 담낭 주변 간실질의 손상을 최소화하기에 적합한 최적 소작 온도를 알아보기 위해 목표 온도에 따라 A군: 7$0^{\circ}C$ (n= 5) , B군: 37$^{\circ}C$ (n= 5) . 그리고 C군: 7$0^{\circ}C$ (n=5) 의 세 군으로 나누어 실험하였으며. 목표 온도에 도달 시점부터 7분간 소작을 지속하였다. 소작 전후에 담낭의 록. 높이 길이를 측정하였으며 소작후 담낭의 용적 갑 소율을 산출하기 비교하였다. 또한 가온된 담즙에 의하여 담낭벽과 담낭 주변 간 실질의 손상 부를 육안과 현미경으로 조사하였다 결과: 담낭의 용적 감소율은 A. B. 7각 군에서 각각 47.7%. 417% 42.7% 였다 (p〉.05) 총 15예 모든 때에서 7$0^{\circ}C$ 에서 담낭벽의 투명도와 탄력성의 소실을 볼 수 있었으며 . B군과 C 군의 10예 중 9예에서 3$0^{\circ}C$ 에서 담낭 주변 판 피막의 위측이 있었다. B군과 C군에서 담낭주 변 간실질 손상의 펑균 두께는 각각 5.4 mm 와 9.8 mm 였다. A군에서는 오직 한 예에서만 간실질의 미미한 육안적 변화만 관찰되었으나 현미경적 검사에서는 세 군 모두에서 담낭 점막 의 완전한 응고 괴사(coagulation necrosis)를 보였다. 결론: 고주파 열치료는 암성 간 낭종 또는 신장 낭종을 포함한 증상이 있는 낭종의 치료에 활용 될 수 있을 것으로 기대된다. Purpose: To determine whether radiofrequency thermal ablation can be used to treat benign cystic lesions in a porcine gallbladders model. Materials and Methods: This experimental study of radiofrequency thermal ab1ation involved the use of 15 exvivo porcine gallbladders and 15-G expandable needle electrodes. To investigate optimal temperature parameters, three groups of five were designated according to target temperature: Group A: 7$0^{\circ}C$; Group B: 8$0^{\circ}C$; Group C: 9$0^{\circ}C$. After the target temperature was reached, ablation lasted for one minute. Gallbladder width, height and length were measured before and after ablation, and the estimated volume reduction ratios of the three groups were compared. Whether adjacent liver parenchyma around the gallbladder fossa was ablated by heat conducted from hot bile was also determined, and the thickness of the a71ate4 area of the liver was measured. Results: The volume reduction ratio in Group A, B and C was 42.7%, 41.7% and 42.9%, respectively (p〉.05). In all 15 cases, gallbladder walls lost their transparency and elasticity at about 7$0^{\circ}C$. In nine of ten cases in Groups B and C, the hepatic capsule around the gallbladder fossa was retracted at about 8$0^{\circ}C$. The mean thickness of liver parenchymal damage adjacent to the gallbladder was 5.4 mm in Group B and 9.8 mm in Group C. In Group A livers, only one case showed minimal gradual parenchmal change. Microscopically, all three groups showed complete coagulation necrosis of the wall. Conclusion: On the basis of this feasibility study, radiofrequency thermal ablation is potentially suitable fur the ultrasound-guided treatment of symptomatic cystic lesions including benign hepatic or renal cyst.

종양 표적 자기공명 분자영상

송호택,서진석 대한의사협회 2009 대한의사협회지 Vol.52 No.2

Magnetic resonance (MR) imaging has been widely used in the clinic because of the benefit of high spatial and temporal resolution, and the excellent anatomical tissue contrast. Cancer-targeted MR molecular imaging comprises 3 major components: a relevant molecular target which is specifically highly expressed on the membrane of the cancer cell; a target specific imaging probe which is composed of superparamagnetic iron oxide nanoparticle coreconjugated target specific ligand such as antibody, peptide, and molecules; MR imaging hardware and software which are sensitive to the imaging probe. Among the various molecular targets, HER2/neu receptor antibody, folic acid, and arginine-glycine-aspartic acid (RGD) are well known targeting ligands. The sensitivity of the cancer-targeted MR imaging is affected by the magnetic susceptibility of the T2 contrast agent, resolution of the image, targeting efficiency of the imaging probe, and image acquisition pulse sequence. Recently, successful cancer-targeted MR imaging with T1 contrast agent and cancer-specific molecular MR imaging using innate contrast of the cancer cell by chemical exchange phenomenon without using the imaging probe has been introduced. Cancer-targeted MR molecuar imaging is a robust diagnostic method to detect cancer at the cellular stage of the cancer development and it would help improve early detection rate of the cancer.

GS/SG 프로브를 이용한 4-Port Calibration의 Thru 제작

송호택(Hotaek Song),이승환(Seunghwan Lee),김태호(Taeho Kim),송승제(Seungje Song),나완수(Wansoo Nah) 대한전기학회 2014 대한전기학회 학술대회 논문집 Vol.2014 No.7

Quantitative Assessment of Tumor Responses after Radiation Therapy in a DLD-1 Colon Cancer Mouse Model Using Serial Dynamic Contrast-Enhanced Magnetic Resonance Imaging

안성준,송호택,금웅섭,안찬식,임준석,이승구,서진석 연세대학교의과대학 2012 Yonsei medical journal Vol.53 No.6

Purpose: The purpose of this study was to investigate the predictability of pretreatment values including Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) derived parameters (Ktrans, Kep and Ve), early changes in parameters (Ktrans, tumor volume), and heterogeneity (standard deviation of Ktrans) for radiation therapy responses via a human colorectal cancer xenograft model. Materials and Methods: A human colorectal cancer xenograft model with DLD-1 cancer cells was produced in the right hind limbs of five mice. Tumors were irradiated with 3 fractions of 3 Gy each for 3 weeks. Baseline and follow up DCE-MRI were performed. Quantitative parameters (Ktrans, Kep and Ve) were calculated based on the Tofts model. Early changes in Ktrans, standard deviation (SD) of Ktrans, and tumor volume were also calculated. Tumor responses were evaluated based on histology. With a cut-off value of 0.4 for necrotic factor, a comparison between good and poor responses was conducted. Results: The good response group (mice #1 and 2) exhibited higher pretreatment Ktrans than the poor response group (mice #3, 4, and 5). The good response group tended to show lower pretreatment Kep, higher pretreatment Ve, and larger baseline tumor volume than the poor response group. All the mice in the good response group demonstrated marked reductions in Ktrans and SD value after the first radiation. All tumors showed increased volume after the first radiation therapy. Conclusion:The good response after radiation therapy group in the DLD-1 colon cancer xenograft nude mouse model exhibited a higher pretreatment Ktrans and showed an early reduction in Ktrans, demonstrating a more homogenous distribution.

Determination of Optimal Imaging Mode for Ultrasonographic Detection of Subdermal Contraceptive Rods: Comparison of Spatial Compound, Conventional, and Tissue Harmonic Imaging Methods

김성준,서경,송호택,서진석,윤춘식,류정아,박정선,김아현,박아영,김예나 대한영상의학회 2012 Korean Journal of Radiology Vol.13 No.5

Objective: To determine which mode of ultrasonography (US), among the conventional, spatial compound, and tissue-harmonic methods, exhibits the best performance for the detection of Implanon® with respect to generation of posterior acoustic shadowing (PAS). Materials and Methods: A total of 21 patients, referred for localization of impalpable Implanon®, underwent US, using the three modes with default settings (i.e., wide focal zone). Representative transverse images of the rods, according to each mode for all patients, were obtained. The resulting 63 images were reviewed by four observers. The observers provided a confidence score for the presence of PAS, using a five-point scale ranging from 1 (definitely absent) to 5 (definitely present), with scores of 4 or 5 for PAS being considered as detection. The average scores of PAS, obtained from the three different modes for each observer, were compared using one-way repeated measure ANOVA. The detection rates were compared using a weighted least square method. Results: Statistically, the tissue harmonic mode was significantly superior to the other two modes, when comparing the average scores of PAS for all observers (p < 0.00-1). The detection rate was also highest for the tissue harmonic mode (p < 0.001). Conclusion: Tissue harmonic mode in uS appears to be the most suitable in detecting subdermal contraceptive implant rods. Objective: To determine which mode of ultrasonography (US), among the conventional, spatial compound, and tissue-harmonic methods, exhibits the best performance for the detection of Implanon® with respect to generation of posterior acoustic shadowing (PAS). Materials and Methods: A total of 21 patients, referred for localization of impalpable Implanon®, underwent US, using the three modes with default settings (i.e., wide focal zone). Representative transverse images of the rods, according to each mode for all patients, were obtained. The resulting 63 images were reviewed by four observers. The observers provided a confidence score for the presence of PAS, using a five-point scale ranging from 1 (definitely absent) to 5 (definitely present), with scores of 4 or 5 for PAS being considered as detection. The average scores of PAS, obtained from the three different modes for each observer, were compared using one-way repeated measure ANOVA. The detection rates were compared using a weighted least square method. Results: Statistically, the tissue harmonic mode was significantly superior to the other two modes, when comparing the average scores of PAS for all observers (p < 0.00-1). The detection rate was also highest for the tissue harmonic mode (p < 0.001). Conclusion: Tissue harmonic mode in uS appears to be the most suitable in detecting subdermal contraceptive implant rods.

Magnetic Resonance Arthrographic Dissection of Posterolateral Corner of the Knee: Revealing the Meniscofibular Ligament

이영한,이영한,송호택,김성준,김성재,서진석 연세대학교의과대학 2012 Yonsei medical journal Vol.53 No.4

Purpose: To evaluate meniscofibular ligament (MFibL) at the posterolateral corner of the knee joint on the magnetic resonance arthrography (MRA) with 70° knee flexion. Materials and Methods: The MRA of the knee joint was performed at 70° knee flexion. Eighteen patients (19 knee joints) underwent scanning of sagittal,coronal, and axial fat-suppressed T1 weighted images (T1FS), and coronal fat-suppressed T2 weighted images. Sagittal three-dimensional (3D) gradient echo (GRE) images were also obtained. Retrospective review of 19 knee MRA studies was independently performed by two musculoskeletal radiologists. The statistical significance was proved by chi-square test. Results: The MFibL ligament was optimally demonstrated on the far lateral sagittal 3D GRE and T1FS MRA images. The MFibL appeared as a curvilinear or straight hypointense band of variable thickness, extended from the posterolateral meniscus to upper anteromedial aspect of the fibular head. The MFibL was demonstrated with scale 2 (more than a half length of the ligament) by both reviewers in 73.68% (n=14/19) of the knee 3D GRE images and 89.47% (n=17/19) of the knee T1FS images. The visualization on T1FS and that on GRE were not statistically different from each other (p>0.05). The interobserver agreements were significantly good on both 3D GRE and T1FS images in detecting the ligament (kappa values, 0.642 and 0.683, respectively). Conclusion: The MFibL is well visualized on the far lateral sagittal MRA at 70° knee flexion, which could potentially be useful in recognizing structures in the posterolateral corner of the knee, including the MFibL.

말초신경 포획 및 압박 증후군의 자기공명영상 소견

김성준,최진영,송호택,허용민,서진석 대한영상의학회 2005 대한영상의학회지 Vol.52 No.2

Clinical Feasibility of Synthetic Magnetic Resonance Imaging in the Diagnosis of Internal Derangements of the Knee

이지숙,이영한,송호택,서진석 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.2

Objective: To evaluate the feasibility of synthetic magnetic resonance imaging (MRI) compared to conventional MRI for the diagnosis of internal derangements of the knee at 3T. Materials and Methods: Following Institutional Review Board approval, image sets of conventional and synthetic MRI in 39 patients were included. Two musculoskeletal radiologists compared the image sets and qualitatively analyzed the images. Subjective image quality was assessed using a four-grade scale. Interobserver agreement and intersequence agreement between conventional and synthetic images for cartilage lesions, tears of the cruciate ligament, and tears of the meniscus were independently assessed using Kappa statistics. In patients who underwent arthroscopy (n = 8), the sensitivity, specificity, and accuracy for evaluated internal structures were calculated using arthroscopic findings as the gold standard. Results: There was no statistically significant difference in image quality (p = 0.90). Interobserver agreement (κ = 0.649− 0.981) and intersequence agreement (κ = 0.794−0.938) were nearly perfect for all evaluated structures. The sensitivity, specificity, and accuracy for detecting cartilage lesions (sensitivity, 63.6% vs. 54.6−63.6%; specificity, 91.9% vs. 91.9%; accuracy, 83.3−85.4% vs. 83.3−85.4%) and tears of the cruciate ligament (sensitivity, specificity, accuracy, 100% vs. 100%) and meniscus (sensitivity, 50.0–62.5% vs. 62.5%; specificity, 100% vs. 87.5−100%; accuracy, 83.3−85.4% vs. 83.3−85.4%) were similar between the two MRI methods. Conclusion: Conventional and synthetic MRI showed substantial to almost perfect degree of agreement for the assessment of internal derangement of knee joints. Synthetic MRI may be feasible in the diagnosis of internal derangements of the knee.

Quantitative Assessment and Ligament Traceability of Volume Isotropic Turbo Spin Echo Acquisition (VISTA) Ankle Magnetic Resonance Imaging: Fat Suppression versus without Fat Suppression

조경은,윤춘식,송호택,이영한,임대건,서진석,김성준 대한자기공명의과학회 2013 Investigative Magnetic Resonance Imaging Vol.17 No.2

Purpose : To compare the image quality and ligament traceability in ankle images obtained using Volume Isotropic Turbo Spin Echo Acquisition (VISTA) MRI with and without fat suppression. Materials and Methods: The signal-to-noise ratios (SNRs) in images from a phantom and from the ankle of a volunteer were compared. Ten ankles from 10 non-symptomatic volunteers were imaged for comparisons of contrast ratio (CR) and ligament traceability. All examinations were performed using VISTA sequences with and without fat suppression on a 3T MRI scanner. The SNRs were obtained from images with subjects and without subjects (noise-only). Contrast ratios from images of the 10 ankles were acquired between fluid and tendon (F-T), F-cartilage (C), F-ligament (L), fat (f)-T, f-C and f-L. Two musculoskeletal radiologists independently scored the traceability of 7 ligaments, in sagittal, axial and coronal images respectively, based on a 4-point scale (1 as not traceable through 4 as clearly traceable). The Wilcoxon signed-rank test was used to compare the CR. Fisher’s exact test and Pearson’s chi-squared test were used to compare the ligament traceability. Results: The SNRs did not differ significantly between the two sequences except in bone marrow. VISTA SPAIR showed the higher CR only in F-T (p = 0.04), whereas VISTA showed higher CR in f-T (p = 0.005), f-C (p = 0.005) and f-L (p =0.005). The calcaneofibular ligament traceability with VISTA was superior to that obtained with VISTA SPAIR (p < 0.05) in all planes. Conclusion: VISTA showed significant superiority to VISTA SPAIR in tracing CFL due to the superior CR between fat and ligament.