Principles for magnetic resonance examination in case of the cervical cancer

Abstract

Magnetic resonance (MR) is the optimal, non-invasive method that allows for precise determination of the degree of cervical cancer progression. It also facilitates the evaluation of tumor volume and structure as well as infiltration of adjacent tissue/organs and enlargement of lymph nodes. Proper qualification and appropriate preparation of patients for the examination is a necessary condition for securing patient's safety and obtaining good quality images. Presently, MR of the lesser pelvis should be performed for most women before any treatment will be initiated. However, an absolute contraindication for the examination is the presence of a pacemaker, cochlear implant, metallic foreign object in the eye ball, metallic surgical clips and lack of verbal contact with the patient, especially deafness. Relative contraindications are pregnancy, especially in the first trimester, claustrophobia, metal foreign objects in soft tissues, metal orthopedic implants, prosthetic heart valve, dental implants, monitoring devices, dosing devices (e.g. insulin pump), permanent make-up or tattoo.

Magnetic resonance imaging and endorectal ultrasound for diagnosis of rectal lesions

“…However, it has to be stressed that unlike for ultrasound, there are a number of absolute and relative contraindications for MRI (Table 2 ). The examination can be performed in pregnant women, but without contrast media administration and using a limited number of sequences [ 29 , 30 ].…”

“…The examination can be performed in pregnant women, but without contrast media administration and using a limited number of sequences [ 29 , 30 ].…”

“…On the other hand, MRI’s usefulness, especially in minute lesions, is limited by various artifacts related to the patient’s condition (e.g., respiratory and cardiac motion, vascular pulsation, nearby located small cysts, liver steatosis and iron accumulation, etc.) as well as artifacts and pitfalls related to the scanner and/or magnetic elements inside of the examined patient (i.e., aliasing, black boundary, chemical shift, entry slice phenomenon, Gibbs energy, magnetic susceptibility, moiré fringes, RF overflow, shading, slice-overlap, susceptibility, zebra stripes, zippers) [ 30 , 61 , 62 ]. This examination technique is also limited because of its cost and insufficient availability in many institutions.…”

“…In a problematic situation, high signal in DWI and low on ADC maps, as well as low ADC values, could also be helpful, since in metastatic infiltration similar features are seen for the tumor and nodes. However, the main limitation of the method is the relatively large size of the ROI (≥1 cm 2 ) and at least three or four different b values used during the acquisition of the DWI sequence [ 30 ]. Attenberger et al [ 38 ] found that ADC measurements and functional parameters were useful in differentiating N stages.…”