AbstractsMedical & Health Science

High resolution MRI in patients with stroke or Cushing’s disease

by A.A.J. de Rotte




Institution: Universiteit Utrecht
Department:
Year: 2015
Keywords: Magnetic Resonance Imaging; Carotid artery stenosis; Cerebral infarcts; Pituitary microadenoma; Cushing's disease
Record ID: 1250821
Full text PDF: http://dspace.library.uu.nl:8080/handle/1874/310942


Abstract

With 3.0 T MRI it is possible to obtain high-detailed images of carotid plaque components. Consequently, in the last decade literature had demonstrated that visualization of plaque components enables to differ groups of symptomatic patients with a difference in future stroke risk but similar degrees of carotid artery stenosis. However, these results cannot be translated to higher field strength MRI of 7.0 T until we are able to obtain dedicated plaque component images with a certain level of quality. Our results demonstrate that the challenges of 7.0 T MRI field strength in the neck region. These challenges hamper the consistency and accuracy of 7.0 T MRI of carotid plaques. It is feasible to visualize macroinfarcts at low field strength MRI of 1.5 T. For CMIs, however, 7.0 T or 3.0 T MRI with dedicated (3D) protocols is needed. CMIs are seen more frequently in patients with cognitive impairment compared to patients without cognitive impairment. Furthermore, we demonstrate that CMIs, depicted with 7.0 T MRI, occur with the same pattern as macroinfarcts. Since all patients with CMIs have macroinfarcts as well, the diagnosis of CMIs has limited added diagnostic value for the clinical setting. However, the burden of CMIs in patients with macroinfarcts may be related to (future) cognitive impairment. Therefore, a large-scale evaluation of CMI prevalence in stroke patients, including clinical and cognitive follow-up, is needed to evaluate the clinical value of CMIs in this specific group of patients. The visualization of microadenomas is important for establishing the diagnosis of a pituitary origin of Cushing’s syndrome as well as for the visualization of the actual location of the microadenoma in the pituitary gland, which in turn is crucial for surgical planning. In a retrospectively multicenter study the 7.0 T images enabled the confirmation of some uncertain pituitary lesions obtained with 1.5 T. Furthermore, some lesions which were not visible with 1.5 T were indeed visualized with 7.0 T. These results suggest that 7.0 T MRI of the pituitary gland in patients with Cushing’s disease and with inconclusive results on standard 1.5 T MRI, is the first clinically relevant application of high resolution 7.0 T MRI. However, a prospective study is needed to evaluate whether there are more patients with Cushing’s disease who might benefit from 7.0 T MRI. Besides, to answer the question if 7.0 T MRI is clinically relevant, we first need to evaluate whether 3.0 T MRI performs as good as 7.0 T MRI and whether consensus reading of the 1.5 T MR images is as good as high field strength MRI. If one of these options would be qualitatively equal to the 7.0 T MRI, this would naturally be a far better applicable, more available and cheaper option in clinical medicine.