• 제목/요약/키워드: Contrast-enhanced magnetic resonance angiography

검색결과 46건 처리시간 0.023초

Contrast Enhanced MR Angiography

  • Lee, M.W.;Kim, S.S.;Kim, I.Y.;Na, K.E.;Yi, Y.;Jung, K.J.
    • 한국자기공명학회:학술대회논문집
    • /
    • 한국자기공명학회 2000년도 제17회 학술발표회
    • /
    • pp.33-37
    • /
    • 2000
  • PDF

An Assessment of the Usefulness of Time of Flight in Magnetic Resonance Angiography Covering the Aortic Arch

  • Yoo, Yeong-Jun;Choi, Sung-Hyun;Dong, Kyung-Rae;Ji, Yun-Sang;Choi, Ji-Won;Ryu, Jae-Kwang
    • 방사선산업학회지
    • /
    • 제12권4호
    • /
    • pp.325-332
    • /
    • 2018
  • Carotid angiography covering the aortic arch includes contrast-enhanced magnetic resonance angiography (CEA), which is applied to a large region and usually employs contrast media. However, the use of contrast media can be dangerous in infants, pregnant women, and patients with chronic renal failure (CRF). Follow-up patients informed of a lesion may also want to avoid constant exposure to contrast media. We aimed to apply time-of-flight (TOF) angiography to a large region and compare its usefulness with that of CEA. Ten patients (mean age, 58 years; range, 45~75 years) who visited our hospital for magnetic resonance angiography (MRA) participated in this study. A 3.0 Tesla Achieva magnetic resonance imaging (MRI) system (Philips, Netherland) and the SENSE NeuroVascular 16-channel coil were employed for both methods. Both methods were applied simultaneously to the same patient. Three TOF stacks were connected to cover the aortic arch through the circle of Willis, and CEA was applied in the same manner. For the quantitative assessment, the acquired images were used to set the regions of interest (ROIs) in the common carotid artery (CCA) bifurcation, internal carotid artery, external carotid artery, middle cerebral artery, and vertebral artery, and to obtain the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR) for the soft tissues. Three radiologists and one radiological resident performed the qualitative assessment on a 5-point scale - 1 point, "very bad"; 2 points, "bad"; 3 points, "average"; 4 points, "good"; and 5 points, "very good" - with regard to 4 items: (1) sharpness, (2) distortion, (3) vein contamination, and (4) expression of peripheral vessels. For the quantitative assessment, we estimated the mean SNR and CNR in each of the 5 ROIs. In general, the mean SNR was higher in TOF angiography (166.1, 205.2, 154.39, 172.23, and 161.95) than in CEA(92.05, 95.43, 84.76, 73.69, and 88.3). Both methods had a similar mean CNR: 67.62, 106.71, 55.9, 73.74, and 63.46 for TOF angiography, and 67.82, 71.19, 60.52, 49.45, and 64.07 for CEA. In all ROIs, the mean SNR was statistically significant (p<0.05), whereas the mean CNR was insignificant (p>0.05). The mean values of TOF angiography and CEA for each item in the qualitative assessment were 4.2 and 4.28, respectively for item 1; 2.93 and 4.55, respectively, for item 2; 4.6 and 3.13, respectively, for item 3; and 2.88 and 4.65, respectively, for item 4. Therefore, TOF angiography had a higher mean for item 3, and CEA had a higher mean for items 2 and 4; there was no significant difference between the two methods for item 1. The results for item 1 were statistically insignificant (p>0.05), whereas the results for items 2~4 were statistically significant (p<0.05). Both methods have advantages and disadvantages and they complement each other. However, CEA is usually applied to a large region covering the aortic arch. Time-of-flight angiography may be useful for people such as infants, pregnant women, CRF patients, and followup patients for whom the use of contrast media can be dangerous or unnecessary, depending on the circumstance.

Differential Subsampling with Cartesian Ordering Contrast-Enhanced Magnetic Resonance Angiography for the Preoperative Assessment of Anterolateral Thigh Flap

  • Yunfeng Shen;Xiucun Li;Chao Zhang;Hai Zhong;Weiqiang Dou
    • Korean Journal of Radiology
    • /
    • 제23권8호
    • /
    • pp.803-810
    • /
    • 2022
  • Objective: To investigate the clinical application of differential subsampling with Cartesian ordering (DISCO) contrast-enhanced (CE) magnetic resonance angiography for anterolateral thigh (ALT) flap transplantation, using operative findings as a reference. Materials and Methods: Thirty patients (21 males and nine females; mean age ± standard deviation, 45.5 ± 15.6 years) who were scheduled to undergo reconstruction with ALT flaps between June 2020 and June 2021 were included in the prospective study. Before ALT flap transplantation, patients were scanned using CE-DISCO imaging. All acquired DISCO images of the 60 lower limbs (both sides from each patient) were analyzed using maximum intensity projection and volume rendering methods. Two experienced radiologists were employed to examine the patterns of the lateral circumflex femoral artery (LCFA), its branches, and perforators and their skin termini, which were compared with the operative findings. Results: Using CE-DISCO, the patterns of the LCFA and its branches were clearly identified in all patients. Four different origins of the LCFA were found among the 60 blood vessels: type I (44/60, 73.3%), type II (6/60, 10.0%), type III (8/60, 13.3%), and type IV (2/60, 3.3%). Owing to a lack of perforators entering the skin, two patients did not undergo ALT flap transplantation. For the remaining 28 patients, the ALT flaps in 26 patients were successfully operated without flap reselection during the operation, while the remaining two patients underwent other surgical procedures due to the thin diameter of the perforator or injury of the perforator during the operation. The success rate of flap transplantation was 92.8% (26/28). All transplanted flaps exhibited good blood supply and achieved primary healing without infection or delayed healing. Conclusion: CE-DISCO imaging can be an effective method for preoperative perforator imaging before ALT flap transplantation.

Acute dural venous sinus thrombosis in a child with idiopathic steroid-dependent nephrotic syndrome: a case report

  • Se Jin Park;Haing-Woon Baik;Myung Hyun Cho;Ju Hyung Kang
    • Childhood Kidney Diseases
    • /
    • 제26권2호
    • /
    • pp.101-106
    • /
    • 2022
  • Nephrotic syndrome (NS) is a hypercoagulable state in which children are at risk of venous thromboembolism. A higher risk has been reported in children with steroid-resistant NS than in those with steroid-sensitive NS. The mortality rate of cerebral venous sinus thrombosis (CVST) is approximately 10% and generally results from cerebral herniation in the acute phase and an underlying disorder in the chronic phase. Our patient initially manifested as a child with massive proteinuria and generalized edema. He was treated with albumin replacement and diuretics, angiotensin-converting enzyme inhibitor, and deflazacort. Non-contrast computed tomography showed areas of hyperattenuation in the superior sagittal sinus when he complained of severe headache and vomiting. Subsequent magnetic resonance imaging revealed empty delta signs in the superior sagittal, lateral transverse, and sigmoid sinuses, suggesting acute CVST. Immediate anticoagulation therapy was started with unfractionated heparin, antithrombin III replacement, and continuous antiproteinuric treatment. The current report describes a life-threatening CVST in a child with steroid-dependent NS, initially diagnosed by contrast non-enhanced computed tomography and subsequently confirmed by contrast-enhanced magnetic resonance imaging, followed by magnetic resonance venography for recanalization, addressing successful treatment.

Diagnosis of Subclavian Steal: Contrast Enhanced 3D MR Angiography vs 2D TOF

  • 이호규;김건언;최중곤;서대철
    • 대한자기공명의과학회:학술대회논문집
    • /
    • 대한자기공명의과학회 2001년도 제6차 학술대회 초록집
    • /
    • pp.136-136
    • /
    • 2001
  • Purpose: Subclavian steal refers to the retrograde flow of blood in a vertebral artery that supplies t ipsilateral shoulder and arm caused by proximal subclavian artery stenosis or occlusion. T purpose of this exhibit is to demonstrate MR findings of subclavian steal on contrast-enhanc 3D (CE 3DMRA) and 2D TOF MR angiography. Method: Four patients(men 3 and women 1, age: 28-78years) with subclavian steal obtained both CE 3DMRA and digital subtraction angiography(DSA) including subclavian arterie Sequential imaging was undertaken during first pass after double dose of Gd-DTPA (0 mM/kg) Injected by a power injector. Coronal source images were obtained with coronal D-fast low angle shot sequence(TR/TE/flip angle=3.8/l.3/35, acquisition time= 10sec/one measurement). Precontrast imaging was subtracted from enhanced images and maximu intensity projection was done. 2D time-of-flight MR angiography(2D TOF) of the carot bifurcation was added in all cases with post-saturation. All studies were review retrospectively.

  • PDF