Are there differences between macrocyclic gadolinium contrast agents for brain tumor imaging? Results of a multicenter intraindividual crossover comparison of gadobutrol with gadoteridol (the TRUTH study)

BACKGROUND AND PURPOSE

Gadobutrol (Gadavist) and gadoteridol (ProHance) have similar macrocyclic molecular structures, but gadobutrol is formulated at a 2-fold higher (1 mol/L versus 0.5 mol/L) concentration. We sought to determine whether this difference impacts morphologic contrast-enhanced MR imaging.

MATERIALS AND METHODS

Two hundred twenty-nine adult patients with suspected or known brain tumors underwent two 1.5T MR imaging examinations with gadoteridol or gadobutrol administered in randomized order at a dose of 0.1 mmol/kg of body weight. Imaging sequences and T1 postinjection timing were identical for both examinations. Three blinded readers evaluated images qualitatively and quantitatively for lesion detection and for accuracy in characterization of histologically confirmed brain tumors. Data were analyzed by using the Wilcoxon signed rank test, the McNemar test, and a mixed model.

RESULTS

Two hundred nine patients successfully completed both examinations. No reader noted a significant qualitative or quantitative difference in lesion enhancement, extent, delineation, or internal morphology (P values = .69-1.00). One hundred thirty-nine patients had at least 1 histologically confirmed brain lesion. Two readers found no difference in the detection of patients with lesions (133/139 versus 135/139, P = .317; 137/139 versus 136/139, P = .564), while 1 reader found minimal differences in favor of gadoteridol (136/139 versus 132/139, P = .046). Similar findings were noted for the number of lesions detected and characterization of tumors (malignant/benign). Three-reader agreement for characterization was similar for gadobutrol (66.4% [κ = 0.43]) versus gadoteridol (70.3% [κ = 0.45]). There were no significant differences in the incidence of adverse events (P = .199).

CONCLUSIONS

Gadoteridol and gadobutrol at 0.1 mmol/kg of body weight provide similar information for visualization and diagnosis of brain lesions. The 2-fold higher gadolinium concentration of gadobutrol provides no benefit for routine morphologic imaging.

Clinico-Radiologic Profile of Spinal Cord Multiple Sclerosis in Adults

MRI is extremely useful for the assessment of initial disease burden and to identify the dissemination of the multiple sclerosis (MS) in time and space. Though MRI of the spinal cord is not used to establish the diagnosis of MS, spinal cord is frequently involved in this disease and there has been increasing emphasis of the spinal imaging in making clinical decision in the management of MS. We undertook a retrospective study of patients with diagnosed MS: 1) to identify radiologic pattern of spinal cord involvement in MS and 2) to correlate radiologic findings with clinical presentation. We reviewed radiologic records from 2004 to 2009 of patients with abnormal T2 signal intensity of the spinal cord with radiologic concern of demyelinating disease. Patients in this cohort who met the Revised McDonald MS Diagnostic Criteria were included in this study. 166 patients were included in the study. There was preference for cervical spinal cord particularly posterior aspect of the spinal cord. Enhancement of the lesions was rare (4.1%). Mean lesion length was 18.2 mm. The average number of lesions per patient was 2.04. Sensory symptoms were predominating and most of the patients had relapsing-remitting course. Patients with sensory symptoms, bladder and bowel involvement and motor symptoms had almost equally distributed lesions among anterior, posterior and central spinal cord. However, all of the patients presented with posterior column signs and gait abnormality had involvement of the posterior spinal cord. Radiologic manifestation of spinal cord MS is extremely variable and can involve the entire length of the spinal cord. Clinical symptoms may or may not be associated with radiologic presentation of the lesions.

JC virus infection of the brain

Since its initial description, there have been significant changes in the epidemiology, pathogenesis, and clinical and imaging manifestations of JCV infection of brain. The most common clinical manifestation is PML. Other recently described CNS manifestations are JCE, JCVGCN, and JCM. Although AIDS is the most common predisposing factor for JCV reactivation, there is increasing incidence of brain manifestations of JCV reactivation in non-HIV settings, including different rheumatologic, hematologic, and oncologic conditions; monoclonal antibody therapy; transplant recipients; primary immunodeficiency syndromes; and even in patients without any recognizable immune deficiency. IRIS may develop secondary to restoration of immunity in HIV-positive patients with PML receiving antiretroviral therapy. This is of profound clinical significance and needs to be diagnosed promptly. Imaging plays a crucial role in the diagnosis of the disease, monitoring of treatment response, identifying disease progression, and predicting prognosis. In this article, current understanding of the epidemiology, pathogenesis, clinical presentations, and all aspects of imaging of JCV infection of the brain have been comprehensively reviewed.

Imaging manifestations of progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease caused by reactivation of JC virus in immunosuppressed patients. The diagnosis is usually suggested on imaging and confirmed by cerebrospinal fluid polymerase chain reaction (PCR) for JC virus DNA. In this article, we review the imaging manifestations of PML on computed tomography (CT), magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), MR spectroscopy, single photon-emission computed tomography (SPECT) and positron-emission tomography (PET), and outline the role of imaging in follow-up and prognostication.

Diffusion tensor imaging in hypertrophic olivary degeneration

SUMMARY

We report DTI and fiber tractography findings in a case of hypertrophic olivary degeneration. A 51-year-old man presented with an abnormal gait and visual difficulties. MR imaging showed enlargement of the right medullary olive and a vascular lesion in the right pontine tegmentum. Fiber tractography showed decreased volume of the right central tegmental tract, supporting a diagnosis of HOD.

Carotid intima media thickness: an independent marker for assessment of macrovascular risk in diabetic patients

In view of the global epidemic of diabetes with India being the hottest reservoir of the disease, it was tried to identify carotid intima media thickness as a surrogate marker for atherosclerosis in diabetic subjects. The study becomes more relevant because diabetes is now considered a disease of the endothelium and a risk equivalent of coronary atherosclerosis (paradigm shift). The study incorporated 41 normotensive patients of diabetes and 31 age and sex matched controls. Plasma glucose and lipid profiles were assessed in all and the carotid intima media thickness was measured. Results were statistically analysed for significance and correlation coefficient between values of plasma glucose and carotid intima media thickness. Results clearly showed that carotid intima media thickness abnormality can pick up atherosclerosis even if the lipid parameters are nearly normal. So it crystallises from this small study that, as a non-invasive test carotid intima media thickness is a better and early predictor of atherosclerosis in diabetic subjects. It also revealed the linear relationship between both fasting and postprandial blood sugar with carotid intima media thickness.