Effects of partial volume and phase shift between fat and water in gradient-echo magnetic resonance-mammography |
| |
Authors: | Michael Peller Michael K. Stehling Harald Sittek Mareike Kessler Maximilian Reiser |
| |
Affiliation: | (1) Department of Diagnostic Radiology, Ludwig Maximilian University, Klinikum Grosshadern, Marchioninistr. 15, 81377 Munchen, Germany |
| |
Abstract: | The signal modulations caused by partial volume effect and phase shift between fat and water signal in gradient-echo magnetic resonance mammography (GRE MR-mammography) have been calculated. Based on this, the theoretical sensitivity and specificity of GRE MR-mammography has been investigated considering different evaluation methods for the gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA)-based signal enhancement. The results show that both in- and out-of-phase sequences suffer from partial volume effects in voxels that contain both fat and water. This can decrease sensitivity to Gd-DTPA uptake in small, fat-embedded lesions or in pathology that contains fat interspersed histologically. Additionally, out-of-phase sequences can suffer from phase cancellation effects that can further decrease their sensitivity to Gd-DTPA uptake. In the worst case signal can actually decrease during Gd-DTPA influx. Determination of enhancement relative to the baseline value can decrease the specificity of GRE MR-mammography in the out-of-phase condition and decrease the sensitivity in the in-phase condition. These effects are less pronounced when enhancement is calculated relative to fat. These effects need to be understood since Gd-DTPA uptake is the prime indicator of malignancy in MR-mammography. |
| |
Keywords: | gradient-echo magnetic resonance-mammography partial volume phase shift |
本文献已被 SpringerLink 等数据库收录! |