1.Dumbbell-shaped Epidural Cavernous Hemangioma: A Case Report.
Jong Myeong LEE ; So Hyun LEE ; Chang Kyu YANG ; Jong Kun KIM ; Hyung Lyul KIM ; Deok Hwa HONG ; Dong Woo KIM
Journal of the Korean Radiological Society 1998;38(2):217-219
It has been reported that cavernous hemangiomas in the spine are generally located in vertebral bodies. Wereport a case of epidural cavernous hemangioma, a very rare condition, at the C7-T2 level. MR images showed adumbbell-shaped mass, with iso and high signal intensity on T1- and T2-weighted images, respectively. The mass wasintensely enhanced following Gd-DTPA injection.
Gadolinium DTPA
;
Hemangioma, Cavernous*
;
Spine
2.The Synthesis and MR Properties of New Macromolecular MR Contrast Agent.
Yongmin CHANG ; Young Hwan CHANG ; Moon Jung HWANG ; Hyun Jung PARK ; Kyungnyeo JEON ; Jongmin LEE ; Kyungsoo BAE ; Bong Seok KANG
Journal of the Korean Society of Magnetic Resonance in Medicine 2002;6(1):35-40
PURPOSE: To evaluate the NMR relaxation properties and imaging characteristics of tissue-specificity for a newly developed macromolecular MR agent. MATERIALS AND METHODS: Phthalocyanine (PC) was chelated with paramagnetic ion, Mn. 2.01g(5.2 mmol) of Phthalocyanine was mixed with 0.37g (1.4 mmol) of Mn chloride at 310 degrees C for 36 hours and then purified by chromatography (CHC13/CH3OH 98/2 v/v, Rf, 0.76) to obtain 1.04g (46%) of MnPC (molecular weight = 2000d), The T1/T2 relaxivity of MnPC was measured in 1.5T(64 MHz) MR using 0.1 mM MnPC. The MR image characteristics of MnPC was evaluated using spin-echo (TR/TE = 500/14 msec) and gradient-echo (FLASH) (TR/TE = 80/4 msec, flip angle = 60) techniques in 1.5T MR scanner. The images of rabbit liver were obtained every 10 minutes up to 4 hours. To study the effect of concentration on image, 20 mM, 50 mM, 100 mM of MnPC were tested. RESULTS: The relaxivities of MnPC at 1.5T (64MHz) were R1 = 7.28 mM-1S-1, R2 = 55.56 mM-1S-1. Compared to the values of Gd-DTPA (R1[= 4.8 mM-1S-1), R2[= 5.2 mM-1S-1]), both T1/T2 relaxivities of MnPC were higher than those of Gd-DTPA. For both of SE and FLASH techniques, the contrast enhancement reached maximum at 10 minutes after bolus injection and the enhancement continued for more than 2 hours. When compared with small molecular weight liver agents such as Gd-EOB-DTPA, Gd-BOPTA and MnDPDP, MnPC was characterized by more prolonged enhancement time. The time course of MR images also revealed biliary excretion of MnPC. CONCLUSION: We developed a new macromolecular MR agent, MnPC. The relaxivities of MnPC were higher than those of small molecular weight Gd-chelate. Hepatic uptake and biliary excretion of MnPC suggests that this agent is a new liver-specific MR agent.
Chromatography
;
Gadolinium DTPA
;
Liver
;
Molecular Weight
;
Relaxation
3.MR Findings of Fibrous Dysplasia.
Won Hee JEE ; Kyu Ho CHOI ; Hyun Seouk JUNG ; Eun Jung LEE ; Jeong Mi PARK ; Ki Tae KIM ; Kyung Sub SHINN ; Youn Soo LEE
Journal of the Korean Radiological Society 1996;34(1):105-110
PURPOSE: To describe the MR findings of fibrous dysplasia. SUBJECTS AND METHODS: MR images of fibrousdysplasia in 13 pathologically proved cases were retrospectively analyzed regarding the signal intensity, hypointense rind, internal septations, cortical disruption, soft tissue extension, and the pattern of contrast enhancement. RESULTS: All cases showed low signal intensity on T1-weighted images. On T2-weighted images, 8cases(62%) were hyperintense and 5 cases(38%) hypointense. Hypointense rind was seen in 10 cases(77%), internal septations in 3 cases(23%), and cystic change in 2 cases(15%). Soft tissue extension was observed in fourcases(31%) including one case with pathologic fracture. After Gd-DTPA infusion, central contrast enhancement wasnoted in 8 cases(73%) and peripheral rim enhancement in 3 cases(23%). Pathologically, hypointensity on T2-weighted images was due to numerous bony trabeculae. CONCLUSION: Hypointensity on T1W1 and hyperintensity(62%) or hypointensity(38%) on T2W1 as well as contrast enhancement in fibrous dysplasia depend on degree of cellularity, collagen, cystic and hemorrhagic changes, and bony trabeculae.
Fractures, Spontaneous
;
Gadolinium DTPA
;
Radiography
;
Retrospective Studies
4.Gadolinium as a CT Contrast Agent: An Experimental Study for the Effects of Injection Parameters in the Rabbit Brain Model.
Hyun Jin KIM ; Hye Young CHOI ; Sun Wha LEE ; Ji Young HWANG
Journal of the Korean Radiological Society 2005;52(1):61-67
PURPOSE: We wanted to investigate the use of gadolinium based contrast agent (Gd-DTPA) for computed tomography (CT), and we also wanted to assess the effects of valuable injection parameters on enhancement in an experimental rabbit brain model. MATERIALS AND METHODS: In vitro, attenuation measurements of serial dilutions of Gd-DTPA and iopromide were compared. In five rabbits, single level dynamic gadolinium-enhanced brain CT studies were obtained using different injection parameters. A comparison CT scan after iopromide administration was performed. The time-attenuation curves of the brain vessel and parenchyma were obtained and the magnitude of enhancement (Hmax) and the time to peak enhancement (Tmax) were analyzed. RESULTS: In vitro, the attenuation coefficient of undiluted Gd-DTPA (2,578 HU) was higher than that of iopromide (1,761 HU) at equimolar concentrations. In 5 rabbits, the time-attenuation curve demonstrated a distinct pattern with peak enhancement only in the brain vessel, but not in the brain parenchyma. There was increasing linear relationship between the injection rate of Gd-DTPA and Hmax, and a declining linear relationship with Tmax. The higher the concentration of Gd-DTPA, the higher Hmax was, but no significant difference was found for the Tmax. Higher volumes of Gd-DTPA revealed a higher Hmax and a delayed Tmax. CONCLUSION: Enhancement of the brain parenchyma on gadolinium-enhanced CT is minimal, while enhancement of the brain vessels is distinctive. The most important factor affecting Hmax of the vessel is the concentration of the contrast medium and the most important factor affecting Tmax of the vessel is volume of the contrast medium. The gadolinium-based contrast agent may be an reasonable alternative contrast agent for brain CT, and especially in cerebral vessels, and it may also be advantageous for brain parenchyma of those patients with BBB dysfunction.
Brain*
;
Gadolinium DTPA
;
Gadolinium*
;
Humans
;
Rabbits
;
Tomography, X-Ray Computed
5.Value of a Bolus-Tagging Method on Contrast-Enhanced Abdominal MR Angiography.
Mi Ra SEO ; Moon Gyu LEE ; Hyuk Jin HONG ; Hyun Kwon HA ; Pyo Nyun KIM ; Yong Ho AUH
Journal of the Korean Radiological Society 1999;41(4):705-711
PURPOSE: To assess the value of the bolus-tagging method for improving the image quality of contrast-enhanced MR abdominal angiography, and to evaluate the relationship between peak arterial enhancement time and patients' age, weight and heart rate. MATERIALS AND METHODS: Contrast-enhanced 3D FISP abdominal MR angiography was performed in 81 patients during a four-month period. The bolus-tagging method was used in a study group comprising 33 patients, and to this end, 1 ml of Gd-DTPA (gadolinium-diethylenetriamine penta-acetic acid) was administered. thirty sequential images (1 image/sec) were then obtained using turbo-FLASH sequencing. After determining peak arterial enhancement time from the time-to-signal intensity curve, optimal scan delay time can be calculated according to the formula used in our patient series. The 48 patients in whom the bolus-tagging method was not used comprised the control group ; in the study group scanning commenced at the optimal scan delay time (and at 10 seconds in the control group) after the administration of 0.2 mM/kg Gd-DTPA using an automatic power injector. Using a three-point scale we evaluated and compared between the two groups the success with which arterial images were obtained. In addition, vascular visibility -an indication of the quality of arteries and veins-was determined using a four-point scale. In the study group, the relationship between peak arterial enhancement time and patients' age, weight heart rate was also assessed. RESULTS: Pure arterial images were successfully obtained in 32 patients (97%) in the study group and in 40 (83%) in the control group. This difference was not statistically significant (p>.05). With regard to vascular visibility, diagnostic arterial images were seen in 30 patients (91%) in the study group and in 33 patients (69%) in the control group; arterial visibility was significantly better in the study group (p=.0197). On the other hand, the diagnostic venous images were seen in 31 patients (94%) in the study group and in 36 (75%) in the control group; there was no significant difference between the two groups (p=.2367). Peak arterial enhancement time increased significantly with age (r=.443, p=.0098); no correlation,however was seen between peak arterial enhancement time and weight (p>.05) or heart rate (p>.05). CONCLUSION: Used with contrast-enhanced 3-D FISP MR abdominal angiography, the bolus-tagging method provides better arterial visibility. Peak arterial enhancement time increased significantly with age.
Angiography*
;
Arteries
;
Gadolinium
;
Gadolinium DTPA
;
Hand
;
Heart Rate
;
Humans
6.Value of a Bolus-Tagging Method on Contrast-Enhanced Abdominal MR Angiography.
Mi Ra SEO ; Moon Gyu LEE ; Hyuk Jin HONG ; Hyun Kwon HA ; Pyo Nyun KIM ; Yong Ho AUH
Journal of the Korean Radiological Society 1999;41(4):705-711
PURPOSE: To assess the value of the bolus-tagging method for improving the image quality of contrast-enhanced MR abdominal angiography, and to evaluate the relationship between peak arterial enhancement time and patients' age, weight and heart rate. MATERIALS AND METHODS: Contrast-enhanced 3D FISP abdominal MR angiography was performed in 81 patients during a four-month period. The bolus-tagging method was used in a study group comprising 33 patients, and to this end, 1 ml of Gd-DTPA (gadolinium-diethylenetriamine penta-acetic acid) was administered. thirty sequential images (1 image/sec) were then obtained using turbo-FLASH sequencing. After determining peak arterial enhancement time from the time-to-signal intensity curve, optimal scan delay time can be calculated according to the formula used in our patient series. The 48 patients in whom the bolus-tagging method was not used comprised the control group ; in the study group scanning commenced at the optimal scan delay time (and at 10 seconds in the control group) after the administration of 0.2 mM/kg Gd-DTPA using an automatic power injector. Using a three-point scale we evaluated and compared between the two groups the success with which arterial images were obtained. In addition, vascular visibility -an indication of the quality of arteries and veins-was determined using a four-point scale. In the study group, the relationship between peak arterial enhancement time and patients' age, weight heart rate was also assessed. RESULTS: Pure arterial images were successfully obtained in 32 patients (97%) in the study group and in 40 (83%) in the control group. This difference was not statistically significant (p>.05). With regard to vascular visibility, diagnostic arterial images were seen in 30 patients (91%) in the study group and in 33 patients (69%) in the control group; arterial visibility was significantly better in the study group (p=.0197). On the other hand, the diagnostic venous images were seen in 31 patients (94%) in the study group and in 36 (75%) in the control group; there was no significant difference between the two groups (p=.2367). Peak arterial enhancement time increased significantly with age (r=.443, p=.0098); no correlation,however was seen between peak arterial enhancement time and weight (p>.05) or heart rate (p>.05). CONCLUSION: Used with contrast-enhanced 3-D FISP MR abdominal angiography, the bolus-tagging method provides better arterial visibility. Peak arterial enhancement time increased significantly with age.
Angiography*
;
Arteries
;
Gadolinium
;
Gadolinium DTPA
;
Hand
;
Heart Rate
;
Humans
7.CT and MRI Findings of Malignant Meningiomas: Comparison with Benign Meningiomas.
Il Kwon YANG ; Kyung Sub SHINN ; Myung Hee CHUNG ; Kyu Ho CHOI ; Han Jin LEE ; Seon Ok JEONG ; Seon Kyo KIM ; Jeong Soo JEON
Journal of the Korean Radiological Society 1995;32(3):375-381
PURPOSE: The purpose is to evaluate the CT or MRI findings to help in the differentiation between benign and malignant meningiomas. MATERIAL AND METHODS: The CT and MRI findings of 8 patients with surgically proven malignant meningioma were reviewed. Four cases of 8 malignant meningiomas and 18 cases of 27 benign lesions were studied with a 1.5T or 0.5T MRI. Radiologic analysis was focused on the heterogeneity of tumor, grade of peritumoral edema, presence of cystic degeneration and calcification, tumoral enhancement pattern, dural enhancement, and tumoral border. RESULT: Histologic types of malignant meningioma were meningotheliomatous (n=4), papillary(n=1), fibroblastic(n=l), angioblastic(n=l), and sarcomatous(n=l). Tumoral Heterogeneity was seen in 8 of 8 malignant lesions(100%) and 8 of 27 benign ones(30%). (p<0.01) Marked peritumoral edema was seen in 8 of 8 malignant lesions(100%) and 2 of 27 benign ones. (7.3%)(p<0.01) Most of malignant lesions(6 of 8 cases, 75%) showed ill defined border. Calcification was not present in malignant lesions in contrast with benign ones (14 of 27 cases, 52%). (p<0.05) No statistical significance was noted in cystic degeneration, dural tail like enhancement or tumoral enhancement pattern between malignant and benign meningiomas. MRI signal intensity of malignant meningiomas was homogeneously or heterogeneously hypointense on T1WI, heterogeneously isointense or hypointense on T2WI and heterogeneous or mixed on Gd-DTPA enhancement study. CONCLUSION: The CT or MRI findings such as heterogeneity, ill defined tumoral border, marked peritumoral edema, and absence of calcification may suggest the possibility of malignancy in meningioma.
Edema
;
Gadolinium DTPA
;
Humans
;
Magnetic Resonance Imaging*
;
Meningioma*
;
Population Characteristics
8.Assessment of Non-permeability of Gd-DTPA for Dynamic Susceptibility Contrast in Human Brain: A Preliminary Study Using Non-linear Curve Fitting.
Seong Ik YOON ; Geon Ho JAHNG ; Hyun Soo KHANG ; Young Joo KIM ; Bo Young CHOE
Journal of the Korean Society of Magnetic Resonance in Medicine 2007;11(2):103-109
To develop an advanced non-linear curve fitting (NLCF) algorithm for performing dynamic susceptibility contrast study of the brain. The first pass effects give rise to spuriously high estimates of Ktrans for the voxels that represent the large vascular components. An explicit threshold value was used to reject voxels. The blood perfusion and volume estimation were accurately evaluated in the T2*-weighted dynamic contrast enhanced (DCE)-MR images. From each of the recalculated parameters, a perfusion weighted image was outlined by using the modified non-linear curve fitting algorithm. The present study demonstrated an improvement of an estimation of the kinetic parameters from the DCE T2*-weighted magnetic resonance imaging data with using contrast agents.
Brain*
;
Contrast Media
;
Gadolinium DTPA*
;
Humans*
;
Magnetic Resonance Imaging
;
Perfusion
9.Dynamic Enhanced MR Imaging is Necessary in the Diagnosis and Staging of Uterine Cervical Cancer?.
Ki Yeol LEE ; Ah Young KIM ; Eun Joo YUN ; Chang Hee LEE ; Mee Ran LEE ; Eun Young KANG ; Cheol Min PARK
Journal of the Korean Radiological Society 1998;38(2):329-333
PURPOSE: To compare the sensitivity and staging accuracy of dynamically enhanced MR imaging(hereafter, DEI)and turbo spin-echo(TSE) T2-weighted imaging(hereafter, T2WI) in cases of cervical carcinoma. MATERIALS AND METHODS: MR images(T2WI and DEI) of 25 cervical carcinoma patients, diagnosed during surgery, were reviewed by tworadiologists. T2WI employed the TSE technique; dynamic MR imaging, the FLASH technique in the axial plane. DEimages were obtained immediately and at 30, 60, 120, and 180 seconds after rapid injection of Gd-DTPA. The degreeof visualization of the tumor, and its invasiveness, were graded as good, fair, or poor. By correlating thehistopathologic results, the accuracy of the two MR imaging techniques was compared. RESULTS: For tumorvisualization, T2WI was good in 13/25 cases (52%), fair in 3/25(12%), and poor in 9/25(36%); DEI was good in5/25(20%), fair in 7/25(28%), and poor in 13/25 cases (52%). CONCLUSION: For the detection and staging of cervicalcarcinoma, T2WI is superior to DEI. For the diagnosis and staging of cervical carcinoma, DEI is thereforeunnecessary.
Diagnosis*
;
Gadolinium DTPA
;
Humans
;
Magnetic Resonance Imaging*
;
Uterine Cervical Neoplasms*
10.MR findings of craniopharyngioma.
Sung Moon LEE ; Young Hoon WOO ; Yang Goo JOO ; Soo Jhi SUH
Journal of the Korean Radiological Society 1992;28(6):805-809
Craniopharyngioma is a benign, slow-growing tumor that constitues 3-9% of all intracranial tumors, and arises from epithelial remnants of the Rathke's pouch. We analized MR (2.0T) findings of ten cases with surgically proved craniopharyngioma retrospectively. CT was avilable in five cases, and Gd-DTPA was used in six cases. Characteristic findings of craniopharyngioma in MRI included multilocularity and variable signal intensities within each loculus that were more prominent in T1WI. Detection rate of calcification in MR was 60%. Six cases with Gd-DTPA enhancement revealed irregular or rim-like enhancement. MRI provides useful informations regarding the location, extent and biochemical characteristics of the oraniopharyngioma as well as its relationship to the neighboring structures which will be valuable in planning surgical resection.
Craniopharyngioma*
;
Gadolinium DTPA
;
Magnetic Resonance Imaging
;
Pheniramine
;
Retrospective Studies