"Electromagnetc Fields In- Duced In a Solid Cylindrical Volume Conductor Due to Switching of Mri Z Gradient Field: Application to Peripheral Nerve Stimulation"
| dc.contributor.advisor | Kidane, Tesfaye (PhD) | |
| dc.contributor.author | Debela, Getachew | |
| dc.date.accessioned | 2019-08-12T14:37:55Z | |
| dc.date.accessioned | 2023-11-18T12:44:30Z | |
| dc.date.available | 2019-08-12T14:37:55Z | |
| dc.date.available | 2023-11-18T12:44:30Z | |
| dc.date.issued | 2018-06-18 | |
| dc.description.abstract | The rapid switching frequency of MRI gradient _elds has a direct relationship to the resolution and hence to the quality of the image. Hence, there is a tendency in the research area to increase the frequency of switching even more. However, the rapid switching frequency can create unwanted peripheral nerve stimulation on the patient's body due to the eddy current induction. In this report a model of the induction of the magnetic and electric _elds as well as the eddy current in a solid cylindrical volume conductor (human body model) due to the switching of the Z gradient coils have been explored analytically. The coils are assumed to carry time harmonic variable current at low frequency. For the analysis, Maxwell's Equations are approximated for this quasi-static situation. Starting from the vector potential expression and taking the _rst order asymptotic approximations of the modi_ed Bessel functions, the solutions for the _eld vectors and the eddy current expression in the cylinder have been found. The application of the problem to peripheral nerve stimulation and the mechanism of PNS in the aspect of its useful application has been discussed. The plot of the eddy current density against the radial distance in the cylinder has shown that the peripheral nerve stimulation is con_ned to the peripheral surface of the patient's body. The solutions have important implication in the design of MRI gradient coils to avoid PNS during scanning and ensure patient safety and comfort. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/12345678/18765 | |
| dc.language.iso | en | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Solid Cylindrical | en_US |
| dc.subject | Peripheral Nerve Stimulation | en_US |
| dc.subject | Electromagnetc Fields | en_US |
| dc.title | "Electromagnetc Fields In- Duced In a Solid Cylindrical Volume Conductor Due to Switching of Mri Z Gradient Field: Application to Peripheral Nerve Stimulation" | en_US |
| dc.type | Thesis | en_US |