[Groin pain in athletes: role of magnetic resonance]. / La pubalgia negli atleti: ruolo della Risonanza Magnetica.

INTRODUCTION: Aim of our work was to evaluate the diagnostic role and potentials of Magnetic Resonance Imaging (MRI) in the study of groin pain in athletes and in the differential diagnosis among the pathological conditions that cause this syndrome. MATERIAL AND METHODS: MRI examinations were performed with a 1.5 T superconductive magnet, and a 0.2 T permanent magnet. Spin-Echo (SE) T1-w, PD, SE T2-w, Gradient-Echo (GE) T2-w and fat saturation sequences were used, on axial, sagittal and coronal scan planes. We performed MRI on twenty-five athletes (22 men and 3 women; age range 17 to 32 years) with chronic groin pain of questionable origin who had been complaining of it for at least 6 months. In 22 cases, radiographs were available; Computed Tomography (CT) had been performed in 3 cases and Ultrasound (US) in 7 cases. Nine patients were submitted to MRI after the symptoms had disappeared. RESULTS: In all patients, MRI provided an accurate depiction of pubic bone alterations and of adjacent myotendinous structures. In 14 cases, osteitis pubis was diagnosed, which was bilateral in 2 cases only (muscular asymmetry of the rectus abdominis was found in 4 of these patients); 4 patients had myotendinous posttraumatic changes (1 hematoma of the psoas muscle and 3 injuries of the abductor muscles of the thigh); 4 patients presented isolated dysmetria of rectus abdominis muscles, with unilateral involvement of the sacroiliac joint in 1 patient; 3 patients had inguinal hernia, surgically confirmed in all cases. DISCUSSION: Osteitis pubis, intended as reactive intraspongiuos edema of the pubic bones, is the most frequent cause of groin pain in athletes. In the early diagnostic phases, both plain films and CT may be negative or not specific. On the other hand, MRI has always proved to be a valuable diagnostic technique in detecting the osteitic change as an area of low signal intensity on T1-w images and of high and homogeneous signal intensity on T2-w scans without fat suppression. Dysmetria of the straight muscles of the abdomen, which may be associated, is always well depicted by MRI on axial planes. Both posttraumatic and dysmetric changes of the muscular structures adjacent to the pubis are well documented by US and MRI. The latter, however, thanks to its multiplanar capabilities, allows better spatial assessment of the alteration, especially if located at peri-insertional level. Possible associated diseases such as the involvement of the sacroiliac joints are also well shown by MRI. Inguinal hernias are easily demonstrated by MRI, which allows the direct visualization of the hernial sac within the inguinal canal. CONCLUSIONS: In our experience, only MRI can permit an accurate and early diagnosis of the different sport-related pubic conditions. MRI is also a valuable tool in monitoring the alterations with reference to their response to treatment, which may also help bring the athletes back to their activities.

[Magnetic resonance imaging of hepatic focal lesions: dynamic contrastographic evaluation with gadolinium versus reticulo-endothelial hepato-specific contrast media]. / Risonanza Magnetica delle lesioni focali epatiche: valutazione contrastografica dinamica con gadolinio vs mezzo di contrasto epatospecifico reticolo-endoteliale.

PURPOSE: To compare the potentials of AMI-25 (Endoren) to those of Gadolinium with the dynamic contrast-enhanced technique in the differential diagnosis of focal liver lesions. MATERIAL AND METHODS: Forty patients with at least one focal liver lesion diagnosed at US underwent MRI. We used a 1.5 T unit and employed single-shot half-Fourier T2-weighted FSE and spoiled gradient-echo T1-weighted sequences before and after Gadolinium injection. Multiple acquisitions were obtained during the arterial, portal and delayed phases. Twenty-four to 48 hours later T2*-weighted GRE and SPGR/90 degrees sequences were obtained after AMI-25 administration. In the characterization of solid lesions the gold standard was biopsy performed with a shearing needle; for the diagnosis of angiomas and of 11 metastatic lesions we considered follow-up and clinical data as important diagnostic elements. RESULTS: We found 12 hepatocarcinomas, 14 metastases, 4 cases of focal nodular hyperplasia (FNH), 4 adenomas and 6 angiomas. The diagnosis was correct and confirmed by the conventional examination in all cases but 2 adenomatous lesions and 2 angiomas. Precontrast studies showed slight hyperintensity in 2 of 4 cases of FNH, while the other 2 lesions appeared isointense and were therefore detected only on postcontrast images, where there was contrast agent uptake during the arterial phase and rapid washout. We found only one central scar hyperintense on T2- and hypointense on T1-weighted images. After AMI-25 administration all lesions appeared isointense to surrounding parenchyma on T2* GRE sequences. Adenomas were isointense in the precontrast phase and postcontrast 3 of them showed strong Gadolinium uptake and rapid washout. After AMI-25 two of the 4 lesions were hyperintense while the other two were isointense to the parenchyma. Four of 6 angiomas exhibited a typical pattern characterized by signal hyperintensity on T2-weighted sequences and on AMI-25-enhanced T1- and T2-weighted sequences. Two angiomas were supposed to be of malignant nature but histology showed the presence of a strong fibrotic component. Hepatocarcinomas could be detected on precontrast images. After Gadolinium administration 10 lesions appeared hyperintense in the arterial phase and 2 were hypointense. After AMI-25 all lesions exhibited homogeneous signal hyperintensity and appeared slightly bigger than on Gadolinium-enhanced images. The metastases were only partly demonstrated by MRI. Postgadolinium studies showed 13 lesions with hyperintense signal in the portal phase. AMI-25 administration detected 14 lesions that appeared slightly bigger than on Gadolinium-enhanced images. CONCLUSIONS: AMI-25 can help also in characterizing primary lesions with an atypical signal pattern after contrast agent administration thanks to its intrinsic capability of accumulating in benign lesions. However it remains difficult to characterize well differentiated hepatocarcinomas and adenomas. Finally, AMI-25 improves MR capabilities in detecting secondary lesions and possible satellite nodules.