Forty-eight patients with oncologic prosthetic devices (modular rotatory shoulder, Kotz, custom made) and metallic means of fixation (Sherman's plates, Ender's rods, etc.) underwent MRI in order to: 1) assess possible physical changes in the magnetic field or the alloys under examination; 2) detect the presence and type of artifacts, and 3) verify the onset of eventual noxious effects of the alloy on the patient. The diagnostic investigation was preceded by an experimental phase which was characterized by: A) a study of the temperature fluctuations of the alloys when submitted to the magnetic field and to radiofrequency; B) the identification and characterization of the artifacts, as well as C) their physical interpretation. During examination, there was no evidence of any mobilization of the means of fixation, sensation of endogenous heat, or other subjective complaints on the part of the patient. The authors observed that, even in the presence of artifacts, MRI provided good evaluation of the soft tissues around the devices by identifying tumor recurrences in the presence of an oncological prosthesis. MRI was also capable of showing trophic changes in the tissues surrounding the means of fixation. Thus, the method exhibits no contraindications in the study of these patients but, on the other hand, does not allow the evaluation of the integrity or mobilization of the prosthetic devices.
"Problemi Inerenti l'Impiego della Risonanza Magnetica nei Pazienti Portatori di Metalli Correntemente Usati nelle Pratiche Ortopediche" “Inherent problems of the use of magnetic resonance in patients with metallic implants currently used in orthopedic practice”
CAPANNA, RODOLFO;
1992-01-01
Abstract
Forty-eight patients with oncologic prosthetic devices (modular rotatory shoulder, Kotz, custom made) and metallic means of fixation (Sherman's plates, Ender's rods, etc.) underwent MRI in order to: 1) assess possible physical changes in the magnetic field or the alloys under examination; 2) detect the presence and type of artifacts, and 3) verify the onset of eventual noxious effects of the alloy on the patient. The diagnostic investigation was preceded by an experimental phase which was characterized by: A) a study of the temperature fluctuations of the alloys when submitted to the magnetic field and to radiofrequency; B) the identification and characterization of the artifacts, as well as C) their physical interpretation. During examination, there was no evidence of any mobilization of the means of fixation, sensation of endogenous heat, or other subjective complaints on the part of the patient. The authors observed that, even in the presence of artifacts, MRI provided good evaluation of the soft tissues around the devices by identifying tumor recurrences in the presence of an oncological prosthesis. MRI was also capable of showing trophic changes in the tissues surrounding the means of fixation. Thus, the method exhibits no contraindications in the study of these patients but, on the other hand, does not allow the evaluation of the integrity or mobilization of the prosthetic devices.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
