Gadodiamide injection at 0.1 and 0.3 mmol/kg body weight: a phase III double-blind,parallel, randomised clinical investigation of known or suspected cenctral nervous system lesions at 1.5 T

We studied 78 patients with clinically suspected central nervous system abnormalities (66 intracranial, 12 spinal) by MRI before and after adminis-tration of the nonionic contrast medium gadodiamide injection. A parallel, double-blind, randomised design was followed. Two dosages were used: 38 patients underwent studies with 0.1 mmol/kg body weight (b.w.) and 40 with 0.3 mmol/kg b. w. MRI showed abnormalities in 36 of the 38 patients receiving the lower dose and 39 of the 40 patients receiving the higher dose. In 3 patients from each group more lesions were seen following injection than before. The contrast medium improved the delineation of abnormal structures and assessment of tumour size and increased their signal intensity indices in both groups, but especially at the higher dose. Adminis-tration of gadodiamide injection provided more diagnostic information in about 75% of the patients, independently of the dose. There were no reports of discomfort, but 7 patients reported adverse events considered unrelated to the gadodiamide injection. The two doses were found to be equally safe and efficient for diagnosis.     

Comparison of the safety of the standard dose and a higher dose of gadodiamide injection for MR imaging of the central nervous system

This study compared the safety and tolerability of gadodiamide injection at the standard dose (0.1 mmol/kg) and at a higher dose (0.3 mmol/kg) in 289 patients participating in a parallel group multiple independent trial program. All patients had a known or suspected central nervous system lesion necessitating investigation with contrast mediumenhanced magnetic resonance imaging. Safety assessments were made before and after injection of the contrast medium, and 1 day later. No adverse events were judged to be related to gadodiamide injection, and only 3.5% of the patients in each dose group reported adverse events that had an uncertain relationship to the contrast medium; both doses were therefore well tolerated. Headache was the most frequently reported event (2%). There were no significant injection-related changes in neurologic status, laboratory test results, or vital signs. The data obtained indicate that the higher dose of gadodiamide injection is as safe and well tolerated as the standard dose.     

Contrast-enhanced MR imaging of the liver: Comparison between Gd-BOPTA and mangafodipir

The purpose of the study was to evaluate the MR contrast agents gadolinium benzyloxypropionictetro-acetate (Gd-BOPTA) and Mangafodipir for liver enhancement and the lesion-liver contrast on T1W spin-echo (SE) and gradient-recalled-echo (GRE) images. Fifty-one patients (three groups of 17 patients each) with known or suspected liver lesions were evaluated with T1W SE (300/12) and GRE (77-80/2.3-2.5/80°) images before and after intravenous (IV) Gd-BOPTA (0.1 or 0.05 mmol/kg) or Mangafodipir (5 μmol/kg) in phase II to III clinical trials. Quantitative analysis by calculating liver signal-to-noise ratio (SNR), lesion-liver contrast-to-noise ratio (CNR), and spleen-liver CNR was performed. Liver SNR and spleen-liver CNR were always significantly increased postcontrast. SNR was highest after application of 0.1 mmol/kg Gd-BOPTA (51.3 ± 3.6, P < .05). CNR was highest after Mangafodipir (?22.6 ± 2.7), but this was not significantly different from others (P = .07). Overall, GRE images were superior to SE images for SNR and CNR. Mangafodipir and Gd-BOPTA (0.1 mmol/kg) provide equal liver enhancement and lesion conspicuity postcontrast. By all criteria, contrast-enhanced T1-weighted GRE were comparable to SE images.     

Gadodiamide injection as a contrast medium for MRI of the central nervous system: a comparison with gadolinium-DOTA

The tolerance and diagnostic efficacy of a new nonionic, intravenous MRI contrast medium, gadodiamide injection (Omniscan^®) are reported and compared with those of gadolinium-DOTA after completion of a double-blind, randomized, parallel study in 60 patients using a dose of 0.1 mmol/kg. Two patients were excluded from the statistical analysis after trial entrance since no contrast medium was injected. The indications for the MRI examination were known or suspected CNS lesions. Vital signs, chemical and haematological parameters were monitored. No significant abnormalities were observed, confirming the excellent tolerance of both contrast media. The usefulness of gadolinium-containing contrast media was again documented, since in 8.6% (5/58) of the patients the lesion(s) could be seen only after injection. Contrast enhancement was seen in 87.8% (43/49) of the patients with abnormal findings, and provided additional diagnostic information in 24.5% (12/49). Lack of contrast enhancement in 12.2% (6/49) of patients with abnormal findings was a significant negative finding.     

MRI of spondylodiscities: contribution of gadolinium-DTPA and fat suppression sequence

Twenty-six patients with a clinical diagnosis of spondylodiscitis were examined with non-contrast and contrast-enhanced MRI in order to define the contribution of gadolinium-DTPA (Gd-DTPA) and different pulse sequences, including a fat suppression sequence (SPIR). Spin echo (SE) T1-weighted images before and after Gd-DTPA injection and SE T2-weighted images were obtained in all patients. Twelve patients were also examined using the SPIR sequence following Gd-DTPA injection. Signal intensity and morphological features of the disc and vertebral lesions were then evaluated. The SE T1-weighted sequence with Gd-DTPA was very effective in showing the pathological changes at the level of the disc as an area of low signal intensity surrounded by a peripheral rim of enhancement in 24 of 26 cases (92%). This feature was not visible on non-enhanced images. As regards contiguous vertebral lesions this sequence was less informative, since in 8 of 26 cases (31%) the vertebral lesions became isointense and therefore not detectable. In 12 cases there was extension into the surrounding structures (spinal canal and/or paravertebral tissues). An enhanced SE T1-weighted sequence provided good anatomical definition of the extension of the infection in the spinal canal in all cases with this type of involvement (7 of 12). Regarding the 7 cases with paravertebral extension, no extension was visible in 1 case due to the reduced contrast with the surrounding fat following Gd-DTPA injection. The enhanced SPIR sequence was very effective, particularly in detecting the lesions in the vertebral bodies, avoiding the limitation of the enhanced SE T1-weighted sequence. The SPIR sequence was also effective in showing the extension within the spinal canal and the paravertebral fat. On the basis of our results the combination of a SE T1-weighted sequence without contrast and SPIR sequence with Gd-DTPA seems to be the best approach in cases of spondylodiscitis. Correspondence to : M. A. Cova     

Synovial cysts of the lumbar spine: CT and MRI correlations

Intraspinal synovial cysts were diagnosed in six patients during a 5-year period and retrospectively studied. Plain films of the lumbar spine showed degenerative changes in all patients. Lumbar myelography showed a posterior and lateral defect caused by extradural compression. Using CT without constrast enhancement established the diagnosis in five of the six-patients. in four cases MRI was performed, three before and after injection of gadolinium diethyline-triamine penta-acetic acid )Gd-DTPA). Including the patient with a false negative CT, MRI was positive in all patients.     

Fetal MRI of the central nervous system: State-of-the-art

Prenatal ultrasonographic (US) examination is considered as the first tool in the assessment of fetal abnormalities. However, several large-scale studies point out that some malformations, in particular central nervous system (CNS) anomalies, are not well characterized through US. Therefore, the actual malformation severity is not always related to prenatal ultrasound (US) findings.Over the past 20 years, ultrafast Magnetic Resonance Imaging (MRI) has progressively increased as a prenatal 3rd level diagnostic technique with a good sensitivity, particularly for the study of fetal CNS malformations. In fact, CNS anomalies are the most common clinical indications for fetal MRI, representing about 80% of the total examinations.This review covers the recent literature on fetal brain MRI, with emphasis on techniques, safety and indications.     

Fetal magnetic resonance imaging of the central nervous system: a pictorial essay

Prenatal ultrasonography is the primary screening modality for the evaluation of fetal pathology. Ultrafast fetal MRI is a recent development that examines the fetus in utero. The short acquisition times (as short as 400 ms/slice) allow to picture freeze the fetus without the need for fetal sedation. The high spatial resolution, good contrast-to-noise ratio, and the multiplanar capabilities are especially advantageous in pathologies of the fetal central nervous system (CNS). Fetal MRI currently serves as a second-line imaging tool for complex fetal cerebral malformations and pathologies. Fetal ventriculomegaly, lesions within the posterior fossa, and abnormalities in cerebral myelination, migration, and sulcation are particularly well identified.     

A double-blind,comparative study of gadodiamide injection and gadopentetate dimeglumine in MRI of the central nervous system

Summary Seventy-nine patients with known or suspected central nervous system lesions were studied with MRI in a phase III double-blind study. Forty were given gadopentetate dimeglumine (Gd-DTPA) and 39 gadodiamide injection (Gd-DTPA BMA), a new low-osmolar nonionic contrast enhancing medium. The dosage was 0.1 mmol/kg body weight, corresponding to 0.2 ml/kg. Spin-echo sequences were performed before and immediately after injection. The safety and efficacy of the two contrast media were assessed. No changes were observed in blood pressure, heart rate or neurological status. Five adverse effects (two episodes of headaches, two of nausea and one of dizziness) were reported by 2 patients who received gadodiamide injection and 1 who received gadopentetate dimeglumine. All events were mild and their relationship to the contrast media was uncertain. For both contrast media statistically significant changes in serum iron were observed 24 h after injection. More than 70% of the patients had abnormal findings on MRI, and in 56% of these contrast enhancement of the abnormal structure or lesion was seen. Contrast enhancement provided the diagnosis in about 50%, changed it in 40% and increased diagnostic confidence in 95%.     

中枢神经系统结核的MRI诊断

目的：分析中枢神经系统结核的MRI表现,探讨MRI的诊断价值。方法：收集我院自2006年9月-2008年5月的中枢神经系统结核121例,其中颅内结核111例、椎管内结核10例。对所有病例均作常规MRI平扫,静脉注射Gd-DTPA增强,并对其MRI表现作回顾性总结。结果：脑膜结核60例、脑实质结核33例、脑膜并脑实质结核18例,脊膜结核4例、结核性脊髓炎4例、脊膜并脊髓结核2例,合并脑梗死24例、脑积水22例,合并室管膜炎3例、硬膜下积液1例、脊髓空洞4例。结论：MRI是检查中枢神经系统结核的重要和可靠方法。     

Safety of gadodiamide injection in two different age groups

A meta-analyses was performed to evaluate the safety of gadodiamide injection (OMNISCAN®) for magnetic resonance imaging in two different age groups (< 65 years; ≥ 65 years). Data on vital signs, clinical laboratory parameters, and subjectively experienced adverse events were reviewed for 734 patients included in 19 European Phase II and III trials with gadodiamide injection (0.1 mmol/kg body weight or 0.3 mmol/kg body weight) used in magnetic resonance imaging. One hundred sixty-four patients were 65 years of age or older. No statistically significant differences were shown between this population and the population younger than 65 years of age with respect to vital signs or clinical laboratory parameters. A total of 48 adverse events, discomfort excluded, were reported, with no significant difference in frequency between the two age groups. Injection-associated discomfort was significantly (P=.0025) more frequent in the younger (9.2%) than in the older group (2.5%). Gadodiamide injection is in conclusion a safe contrast medium in older as well as in younger patients.     

Radiation myelopathy: significance of gadolinium-DTPA enhancement in the diagnosis

Summary We described two cases of chronic progressive radiation myelopathy (CPRM), in which magnetic resonance imaging (MRI) was of great value for the diagnosis. Gadolinium-DTPA (Gd-DTPA) enhancement delineated precise lesions responsible for Brown-Séquard syndrome caused by CPRM in both cases. This safe, sensitive procedure will be a requisite study in patients who are suspected of CPRM.     

Efficacy of nonionic low-osmolar gadodiamide injection in animals with intracranial mass lesions.

Gadodiamide injection is a nonionic, low-osmolar formulation of a paramagnetic metal chelate complex consisting of gadodiamide and caldiamide sodium. The efficacy of gadodiamide injection as a magnetic resonance (MR) imaging enhancement medium was evaluated by imaging intracranial 9L-glioma lesions induced in rats and naturally occurring lesions in dogs. T1- and T2-weighted spin-echo images were obtained before and after administration of gadodiamide injection at doses of 0.1 and 0.2 mmol/kg. On the precontrast T1-weighted images, the intracranial lesions were not well seen, appearing isointense to normal brain parenchyma. Although the presence of disease was shown unequivocally on the T2-weighted images, the margins of the masses could not be delineated. Postcontrast T1-weighted images were characterized by marked enhancement of the tumor, with no change in signal intensity in the surrounding edematous brain tissue. Gadodiamide injection was efficacious in identifying areas of blood-brain barrier breakdown associated with intracranial masses.     

Invasive central nervous system aspergillosis in bone marrow transplantation recipients: an overview

Invasive central nervous system aspergillosis is being seen with an increased frequency, particularly due to the increased number of immunosuppressed patients. The major cause of invasive central nervous system aspergillosis is bone marrow transplantation. In most cases, aspergillosis develops in the paranasal sinuses and in the lungs, and secondarily spreads to the brain. Imaging of cerebral aspergillosis may present different patterns depending on the lesion's age and the immunologic status of the patient. Lesions of the spinal cord are far less common but has been encountered in our series. In this article we review the clinical and radiologic features of aspergillosis affecting the central nervous system in patients who underwent bone marrow transplantation. Different CT and MR patterns are presented, including pertinent clinical and pathologic material. Significant morbidity and mortality can be associated with this fungal infection, and it is therefore incumbent upon the radiologist to identify intracranial aspergillosis as early as possible so that appropriate therapy can be administered. Electronic Publication     

Contrast-enhanced magnetic resonance angiography of the lower extremities: standard-dose vs. high-dose gadodiamide injection

PURPOSE: To compare the efficacy and safety of two different doses (0.1 and 0.3 mmol/kg of body weight [BW]) of gadodiamide for contrast-enhanced magnetic resonance angiography (ce-MRA) of the lower extremities with intraarterial digital subtraction angiography (IA-DSA). MATERIALS AND METHODS: A total of 30 patients with peripheral arterial occlusive disease underwent IA-DSA and ce-MRA from the aortic bifurcation down to the ankle. Patients were randomized to receive a total dose of 0.1 or 0.3 mmol/kg of BW gadodiamide (Omniscan, Amersham Buchler), administered intravenously as a series of three automatic bolus injections. Ce-MRA was performed with a 1.5-T system using a body phased-array coil, centered stepwise over the calf, thigh, and pelvic region. A fast T1-weighted, three-dimensional gradient-echo sequence was obtained before and after injection of the allocated dose. IA-DSA was performed using the Seldinger technique and a femoral approach. The vessels under investigation were divided into 31 segments, and ce-MRA and IA-DSA image sets were evaluated in a double-blind fashion for the presence of stenosis, presence of collateral vessels, vessel delineation, and overall image quality. Both dose groups were compared with regard to contrast index (CI) and signal- and contrast-to-noise ratios (SNR, CNR). The occurrence of adverse events or side effects was also documented. Sensitivity, specificity, and accuracy were calculated in relation to the results of stenosis grading. RESULTS: A total of 26 patients were entered in the efficacy evaluation, while all 30 patients were included in the safety assessment. The sensitivity, specificity, and accuracy for the 0.1 and 0.3 mmol/kg dose groups were 78.8%/93.0%/88.9% vs. 60.2.%/91.5%/83.2%, respectively. The detection of collaterals was similar to IA-DSA for the 0.3 mmol/kg dose group (30.2% vs. 27.4%), but was lower in the 0.1 mmol/kg dose group (27.3% vs. 12.3%). The high-dose gadodiamide injection proved to be superior to the 0.1 mmol/kg dose group with regard to vessel delineation and overall image quality (P = 0.007 and P = 0.002, respectively). The difference between the two dose groups regarding CI, SNR, and CNR was significant (P = 0.0001), in favor of the 0.3 mmol/kg dose group. No adverse events were observed in any of the patients. CONCLUSION: Ce-MRA with gadodiamide is safe and efficacious. Comparison of two different doses with IA-DSA as the standard of reference showed that the 0.3 mmol/kg dose is superior to the standard 0.1 mmol/kg dose with respect to contrast enhancement, vessel delineation, image quality, and detection of collaterals. However, the 0.1 mmol/kg dose was superior to the high dose in the grading of stenosis.     

Preliminary clinical trial of gadodiamide injection: a new nonionic gadolinium contrast agent for MR imaging.

The safety and efficacy of a newly developed intravenous formulation of the nonionic contrast agent gadolinium diethylenetriaminepentaacetic acid-bis(methylamide), formulated as gadodiamide injection, was investigated. In 30 patients who underwent spin-echo magnetic resonance (MR) imaging before and after contrast agent enhancement, the enhanced images had characteristics judged similar to those of images enhanced by means of available gadolinium compounds. In 15 patients, contrast agent administration was of major diagnostic help, either revealing lesions not apparent without enhancement or providing important lesion characterization. In 12 patients, the lack of abnormal enhancement patterns was important in excluding the presence of disease. In three patients, the contrast agent did not provide information additional to that obtained with the unenhanced T1- and T2-weighted images. No clinically significant changes were observed in vital signs, neurologic status, or laboratory results. The authors conclude that, in this limited series, gadodiamide injection proved to be a safe and useful MR imaging contrast agent for evaluation of the central nervous system and surrounding structures.     

Contrast-enhanced ultra-high-field liver MRI: A feasibility trial

The aim of this study was to investigate the feasibility of dynamic contrast-enhanced 7 T MRI of the liver using an eight-channel radiofrequency (RF) transmit/receive body-coil. 16 healthy subjects were examined on a 7 T MR system utilizing a custom-built eight-channel RF body-coil suitable for RF-shimming. The following data were acquired: (1) steady state free precession imaging, (2) T2w turbo spin echo imaging, (3) T1w in and opposed-phase imaging, (4) T1w 3D FLASH images pre-contrast and in arterial, portal-venous and venous phase and (5) a fat-saturated pre- and post-contrast 2D FLASH sequence. Visual evaluation of (1) the delineation of liver vasculature, (2) the overall image quality, and (3) artifact presence and consequent image impairment was performed. SNR of the liver parenchyma was measured for the contrast-enhanced 2D and 3D FLASH sequences. For statistical analysis, a Wilcoxon-Rank Test was used. Best delineation of non-enhanced liver vasculature and overall image quality was found for 2D FLASH MRI, with only slight improvement in vessel conspicuity after the application of contrast media. T2-weighted TSE imaging remained strongly impaired, falling short of diagnostic relevance and precluding a clinical application. Our results demonstrate the feasibility and diagnostic potential of dedicated contrast-enhanced 7 T liver MRI as well as the potential for non-contrast-enhanced angiographic application.     

MRI在胎儿中枢神经系统中的临床应用

目的探讨MRI在胎儿中枢神经系统发育异常中的应用价值。方法24例孕妇，年龄25～34岁，平均28岁；孕龄20～39周，平均30周。产前例行超声检查后24h内行MR检查，T2WI采用半傅立叶单激励快速自旋回波(HASTE)快速扫描序列，T1WI采用二维快速小角度激励(FLASH)序列。将超声、MRI结果与出生后或引产后随访结果对照。结果24例孕妇共检出胎儿24个。MR T2WI可清楚、直观地显示出大脑实质、脑回、脑沟裂、胼胝体、丘脑、小脑、脑干及脊髓等解剖结构，T1WI质量差于T2WI。超声共显示病灶27个，MRI显示31个。MRI证实超声怀疑的诊断2例，进一步完善诊断10例，与超声诊断一致12例。结论MRI对胎儿中枢神经系统解剖结构的显示优于超声，而且不受孕妇体型、羊水量多少、胎儿颅骨及母体骨盆骨骼影响。在超声检查基础上进行胎儿MR检查，有助于弥补超声的不足，甚至更正超声诊断，可作为产前胎儿检查的辅助措施。     

中枢神经系统肠源性囊肿的MR诊断与鉴别诊断

目的探讨中枢神经系统肠源性囊肿的MRI表现及其鉴别诊断。方法回顾性分析7例经手术和病理证实的肠源性囊肿的临床和MRI资料。结果 7例肠源性囊肿,桥前池1例,椎管内髓外硬膜下6例,3例病变位于颈段,2例位于上段胸段,1例位于腰段。6例椎管内肠源性囊肿,5例囊肿位于脊髓腹侧,均可见"脊髓嵌入征"。多数囊肿T1Wl呈等或稍高于脑脊液信号,T2WI等或稍低于脑脊液信号。6例行MR增强扫描,5例囊壁及囊液均未见强化,1例囊壁轻度强化。结论 MRI对肠源性囊肿的诊断及鉴别诊断有重要价值。     

原发性中枢神经系统淋巴瘤的磁共振成像表现

目的探讨原发性中枢神经系统淋巴瘤（PCNSL）的磁共振成像（MRI）特征及鉴别诊断。方法回顾性分析15例经手术病理证实的PCNSL的MRI表现。结果病理检查均为B细胞来源的弥漫性大B细胞性淋巴瘤。15例PCNSL19个病灶,单发13例（87％）,多发2例（13％）共6个病灶。病灶常位于脑表浅部位和近中线部位,T1wI呈等或稍低信号,T2WI及液体衰减反转恢复序列（FLAIR）呈等或稍高信号,弥散加权成像（DWI）呈高信号。所有病灶均明显强化,增强后病灶大多呈均匀实质团块状或结节状强化,典型的可出现“尖角征”、“握拳征”,3例可见小囊变,呈“硬环征”。结论PCNSL的MRI表现具有一定的特征性,术前MRI检查有助于诊断及鉴别诊断,结合患者影像学及临床资料,术前可作出明确诊断。