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R Kuntz

Publications and source records attributed to R Kuntz.

23 records · Page 2Linked to original sources

Improved clinical echo-planar MRI using spatial-spectral excitation.

Echo-planar imaging (EPI) is markedly susceptible to B0 field distortions and to frequency differences caused by chemical shift, because the phase of the signals is accumulating during the acquisition train. Thus, only water proton signals are usually recorded after frequency-selective suppression of the fat portions of magnetization. Otherwise, a shifted signal frequency from fat results in ghosting artifacts. In this article, a technique is presented working with spatial-spectral excitation for highly selective water or fat EPI. The proposed method allows recording in multislice operation on EPI scanners without irregular gradient or RF pulse shapes. Examples of gradient-echo and spin-echo EPI using spatial-spectral excitation by series of two to eight single slice-selective RF pulses are demonstrated. The method is not sensitive to misadjustments or inhomogeneities of the B1 field, but sufficient homogeneity of the static magnetic field B0 is required. Especially the quality of diffusion-weighted echo-planar images can be markedly improved by the new technique compared to conventional EPI, because artifacts from undesired chemical shift components are completely avoided.

Adult↗

Cerebral vein thrombosis in a case with thromboangiitis obliterans.

Thromboangiitis obliterans is a chronic inflammatory vessel disease that involves predominantly the small and medium-sized arteries and veins of the distal extremities. Appearance and cessation of symptoms are closely related to patterns of tobacco consumption. That cerebral arteries can also be involved is shown by reports of rare cases in which cerebral artery occlusion led to infarction. We report on a 28-year-old man with thromboangiitis obliterans who developed extensive cerebral vein thrombosis after a single episode of cigarette smoking following several years of nonsmoking. Despite extensive evaluation, no other known cause or predisposition of cerebral vein thrombosis could be found. This case suggests that cerebral veins can be involved in thromboangiitis obliterans and patients with thromboangiitis obliterans might be at risk for cerebral vein thrombosis.

Adult↗