Publikationsserver der RWTH Aachen University
Hochauflösende Darstellung des Innenohrs unter Anwendung zweier unterschiedlicher MRT-Sequenzen : Morphologie und pathologische Veränderungen
Abstract
dc:descriptionThe applicability of imaging procedures for the depiction of the inner ear is comprehensive. All age-groups offer enough clinical reason to carry out an exact diagnosis. Children, on account of a possible congenitally defect of the inner ear with the consequences of psycho-social restriction, young to middle-aged adults and old people with acute hearing loss, attacks of dizziness, tinnitus, tumorous and traumatic of the inner ear, all require a very good and precise diagnosis. In summary we can say that HRCT and MRI are not competing but are rather complementary and supplementary diagnostic methods. Important for the diagnostic reliability is the usage of thin slices (max 1 mm for the CT or in the case of MRI, under a millimetre) and high resolution algorithms. The MRI gradient echo and spin echo techniques are suitable diagnostics for the temporal bone area. We compared two sequences, True-FISP and the heavily T2 weighted Turbo Spin Echo sequence, in terms of depiction of anatomic structures and pathological changes of the inner ear. Small structures like modiolus, osseous spiral lamina, superior and inferior vestibular nerve and cochlear nerve are depicted significantly better (p <0.001) by the use of True FISP than by use of TSE, while larger structures like cochlea vestibule and the semicircular canals were detectable similarly well by both sequences. The True FISP sequence showed a higher spectrum on the signal intensity difference between solid structures. Thus pathologic alterations such as acoustic neurinoma and defects of the semicircular canals could be better detected using the True FISP sequence. The susceptibility artifacts in the semicircular canals were visible on the True FISP radiograph however. They were not present on the TSE radiograph. The True FISP as a high resolution examination is suited for the temporal bone imaging, but by the occurrence of field inhomogeneity artifacts we recommend supplementing the examination with a TSE or with a corresponding sequence. The launching of the new CT and MRI imaging techniques have brought an enormous progress for the detailed anatomic rendering of the inner ear as well as for the therapeutic strategy. The above-mentioned imaging methods are an indispensable help for special HNO check-ups. For this the coordination of interdisciplinary cooperation between primary diagnostic specialized disciplines, radiologists and surgeons is essential. The clinical afflictions are not necessarily accompanied with pathological findings on the MRI. In total 48.3% of the tested patient depicted radiologic alteration. The diagnostic optimization brings in any case an advancement in therapeutic possibilities and contributes in this way to progress in medicine.
Degree
thesis:*- Grantor dc:publisher
- Publikationsserver der RWTH Aachen University
- Year dc:date
- 2009
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Pani, Liri
- Contributors dc:contributor
-
- Krombach, Gabriele
Subjects
dc:subject × 7Rights
dc:rights- Statement dc:rights
-
- info:eu-repo/semantics/openAccess
- Language dc:language
- ger