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.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
3.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
4.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
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.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
7.Contrast-Enhanced Three-Dimensional MR Imaging Using a Volumetric Interpolated Breath-hold Examination (VIBE): Clinical Utility in the Evaluation of Renal Tumors.
Young Hwan LEE ; Jeong Min LEE ; Chong Soo KIM
Journal of the Korean Radiological Society 2002;47(6):635-642
PURPOSE: To compare, in terms of technical feasibility, image quality and clinical efficacy, contrast-enhanced three-dimensional (3D) MR imaging using volumetric interpolated breath-hold examination (VIBE) with twodimensional gradient-echo MR imaging for the evaluation of renal masses. MATERIALS AND METHODS: Twenty-three patients with 25 renal masses underwent dynamic MR imaging using a 1.5-T MR system and the 3D VIBE, 2D fast low angle shot (FLASH), and combined fat saturation techniques after the injection of 20 ml of Gd-DTPA. We compared postcontrast 2D FLASH and 3D VIBE images with precontrast 2D FLASH images. For quantitative analysis, the signal-to-noise and lesion to kidney contrast-to-noise ratio of the images were calculated using the three different techniques. For qualitative analysis, two experienced radiologists analyzed the images in terms of artifacts, lesion conspicuity and delineation, and general image quality. Delineation of the anatomy of renal vasculature and pelvocalyceal systems on reconstructed 3D VIBE MIP images was also assessed. RESULTS: Quantitative analysis showed that the SNR of a renal mass was slightly higher at postcontrast 2D FLASH than at 3D VIBE imaging, and the SNR of renal cortex was higher at 3D VIBE than at postcontrast 2D FLASH imaging. The differences were, though, statistically insignificant (p>0.05). The CNR of a renal mass was, however, significantly higher at 3D VIBE than at 2D FLASH imaging (p<0.05). Qualitative analysis showed that general image quality was best at postcontrast 3D VIBE, followed by 2D FLASH and precontrast 2D FLASH imaging, and image artifacts were worst at post-contrast 2D FLASH image (p<0.05). In terms of lesion conspicuity and delineation, 3D VIBE gave the best results and postcontrast images were better than precontrast (p<0.05). Reconstructed angiographic and urographic images using the VIBE technique provided information about the anatomy of the renal vasculature and pelvocalyceal system. CONCLUSION: 3D VIBE MR imaging offers comparable or superior image quality to 2D FLASH, and because it can provide angiograms and urograms may be more useful in the staging work-up of renal malignancies.
Artifacts
;
Gadolinium DTPA
;
Humans
;
Kidney
;
Magnetic Resonance Imaging*
8.Usefulness of Dynamic Magnetic Resonance Imaging in Pituitary Microadenomas.
Chang Soo RHEE ; Eun Young LEE ; Yang Gu JOO ; Hong KIM ; Hee Jung LEE ; Soo Ji SUH
Journal of the Korean Radiological Society 1996;34(3):339-344
PURPOSE: To investigate the usefulness of dynamic MR imaging in the diagnosis of pituitary microadenomas. MATERIALS AND METHODS: Dynamic MR imaging was performed in 31 patients with suspicious pituitary microadenoma. The MR examination was performed on a 2.0T or 1.5T superconductive MR unit using spin echo(SE) technique with arepetition time of 200m sec, echo time of 15 m sec, 128 x 256 matrix and one excitation. Actual sampling time perimage was 26 seconds. The field of view was 25cm and a section thickness of 3mm with 2mm gap was chosen. After arapid hand injection(2-3ml/sec) of Gd-DTPA(0.1 mmol/kg of body weight), dynamic coronal plane MR images were obtained every 20-30 seconds for 3-5 minutes. Between never and ten serial images were usually obtained. After dynamic MR imaging, routine SE T1-weighted images(T1WI) were obtained in the same plane as dynamic images, and detection rates of pituitary microadenoma using dynamic MR imaging and using routine enhanced T1WI, were retrospectively compared. RESULTS: On early dynamic images(30|90 seconds), 23 of 31 adenomas(74.2%) were well visualized, with a clear border ; of particular note is the fact that 11 of the 31 were well visualized at 30-second dynamic image. On late dynamic images(120-180 seconds), six microadeomas(19.4%) were well-visualized and; two(6.5%) were well-visualized throughout on all dynamic images. Meanwhile, 12 of 31 microadenomas(38.7%) were well-visualized on routine Gd-DTPA enhanced T1WI. CONCLUSION: Dynamic MR imaging with Gd-DTPA bolus injection was the most useful technique for the detection of pituitary microadenomas, especially on early-phase dynamic images.
Diagnosis
;
Gadolinium DTPA
;
Hand
;
Humans
;
Magnetic Resonance Imaging*
9.Differentiation of Exudative and Transudative Pleural Effusion: MR Appearances.
Tae Hoon KIM ; Sang Yoon LEE ; Ho Yeong KANG ; Soo Rhan KIM ; Sang Kyu YANG ; So Young SHIN ; Shin Hyung LEE ; Chang Joon LEE
Journal of the Korean Radiological Society 1996;35(5):715-719
PURPOSE: The purpose of this study is to determine whether MR images after intravenous administration of Gd-DTPA can differentiate exudative and transudative pleural effusion. MATERIALS AND METHODS: We studied 18 patients with ten exudative and eignt transudative pleural effusions diagnosed clinically and by thoracentesis. We analysed the relationship between T1 value(normalized to fat) and the ratio of effusion/serum protein of pleuraleffusion. We also assessed the contrast enhancement of exudative and transudative pleural effusion on T1 weighted SE images taken at 15 and 30 minutes after administration of Gd-DTPA. RESULTS: The relationship between the effusion/serum protein ratio and T1 value(normalized to fat) was statistically not significant(r=0.27, P=0.381).On precontrast spin-echo T1W1, mean signal intensity of the transudate was 0.18 (+/-0.04) and that of the exudatewas 0.24(+/-0.07), values which were not significant differences(P>0.05). Postcontrast mean signal intensities of transudates at 15 and 30 were 0.20+/- 0.06 and 0.26+/-0.08, respectively, values which were not significantly higherthan that of precontrast mean signal intensity(P<0.05). Postcontrast mean signal intensity values of exudative pleural effusions at 15 and 30 mimutes(0.32+/-0.06 and 0.39+/-0.06, respectively) were, on the other hand, significantly higher than that of precontrast mean signal intensity(P<0.05). CONCLUSION: Postcontrast T1-weighted SE images at 15 and 30 minutes can be helpful in the differentiation of transudative and exudative pleural effusion.
Administration, Intravenous
;
Exudates and Transudates
;
Gadolinium DTPA
;
Humans
;
Pleural Effusion*
10.Malignant melanoma of the vagina: CT and MR findings.
Woo Kyung MOON ; Seung Hyup KIM ; Hyeong Joon JEON ; Man Chung HAN
Journal of the Korean Radiological Society 1993;29(3):497-500
We report CT and MR findings in tow cases of primary malignant melanoma of the vagina, one arising from cervicovaginal junction mimicking squamous cell carcinoma of the cervix and the other one recurring at vagina after resection. Two cases of malignant melanoma had high-attenuation on CT and high signal intensity on T1-weighted MR images and enhanced well after gadopentetate dimeglumine administration.
Carcinoma, Squamous Cell
;
Cervix Uteri
;
Female
;
Gadolinium DTPA
;
Melanoma*
;
Vagina*