To assess the effect of field strength on magnetic resonance (MR) images, the same healthy subject was imaged at three field strengths: 0.5, 1.0, and 1.5 T. Imaging was performed with three similarly equipped MR imagers of the same generation and from the same manufacturer. The same imaging sequences were used with identical parameters and without repetition time correction for field strength. Imaging was performed in four anatomic locations: the brain, lumbar spine, knee, and abdomen. Quantitative image analysis involved calculation of signal-to-noise ratio, contrast-to-noise ratio, and relative contrast; qualitative image analysis was performed by four readers blinded to field strength. The results of all of the examinations were considered to be of diagnostic value. In general, signal-to-noise ratio and contrast-to-noise ratio were lowest at 0.5 T and highest at 1.5 T; relative contrast was not related to field strength. At qualitative analysis, images obtained at 1.0 and 1.5 T were superior to images obtained at 0.5 T; qualitative differences were less important in locations where there is motion or high magnetic susceptibility differences between tissues (e.g., the spine and abdomen). However, excellent image quality was obtained with all three field strengths.

Use of selective salpingography and fallopian tube recanalization has revolutionized the diagnosis and treatment of infertility. Selective salpingography, a diagnostic procedure in which the fallopian tube is directly opacified through a catheter placed in the tubal ostium, has been used since the late 1980s to differentiate spasm from true obstruction and to clarify discrepant findings from other tests. In fallopian tube recanalization, a catheter and guide wire system is used to clear proximal tubal obstructions. The recanalization procedure is simple for interventional radiologists to perform and is successfully completed in most patients (71%-92%). Pregnancy rates after the procedure have been variable, with an average rate of 30%. The combination of selective salpingography with fallopian tube recanalization has improved the overall management of infertility caused by tubal obstruction. The same catheterization technique used in fallopian tube recanalization is currently being explored for use in tubal sterilization.

Magnetic resonance imaging is a novel noninvasive imaging modality for the assessment of pelvic floor dysfunction. It relies on static sequences with a high spatial resolution to study muscle morphology (levator ani) and fast imaging dynamic sequences during contraction, rest, and straining. Prolapse of the various pelvic compartments is detected with respect to organ position relative to the pubococcygeal line during dynamic phases. Compared with clinical examination, its input appears to be especially invaluable in the posterior compartments (peritoneal and digestive) and to assess complex prolapses involving more than one pelvic compartment. It is also useful for understanding postsurgical recurrences.

We report a case of traumatic urethral tear associated with a rupture of the corpus cavernosum, demonstrated on MRI. We discuss the potential role of a non-invasive preoperative assessment by MRI.

A percutaneous puncture of the upper pole of the kidney above the 11th rib increases the risk of visceral damage. Preoperative evaluation, with the aid of CT scan or MRI, of the risk of pulmonary, splenic, or hepatic injury could be carried out in these cases.