Dynamic contrast-enhanced and diffusion-weighted MR imaging in the characterisation of small, non-palpable solid testicular tumours.

OBJECTIVES: To explore the role of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI), using semiquantitative and quantitative parameters, and diffusion-weighted (DW) MRI in differentiating benign from malignant small, non-palpable solid testicular tumours. METHODS: We calculated the following DCE-MRI parameters of 47 small, non-palpable solid testicular tumours: peak enhancement (PE), time to peak (TTP), percentage of peak enhancement (Epeak), wash-in-rate (WIR), signal enhancement ratio (SER), volume transfer constant (Ktrans), rate constant (Kep), extravascular extracellular space volume fraction (Ve) and initial area under the curve (iAUC). DWI signal intensity and apparent diffusion coefficient (ADC) values were evaluated. RESULTS: Epeak, WIR, Ktrans , Kep and iAUC were higher and TTP shorter in benign compared to malignant lesions (p < 0.05). All tumours had similar ADC values (p > 0.07). Subgroup analysis limited to the most frequent histologies - Leydig cell tumours (LCTs) and seminomas - replicated the findings of the entire set. Best diagnostic cutoff value for identification of seminomas: Ktrans ≤0.135 min-1, Kep ≤0.45 min-1, iAUC ≤10.96, WIR ≤1.11, Epeak ≤96.72, TTP >99 s. CONCLUSIONS: DCE-MRI parameters are valuable in differentiating between benign and malignant small, non-palpable testicular tumours, especially when characterising LCTs and seminomas. KEY POINTS: • DCE-MRI may be used to differentiate benign from malignant non-palpable testicular tumours. • Seminomas show lower Ktrans, Kep and iAUC values. • ADC values are not valuable in differentiating seminomas from LCTs. • Semiquantitative DCE-MRI may be used to characterise small, solid testicular tumours.

MRI, US or real-time virtual sonography in the evaluation of adenomyosis?

PURPOSE: Real-time virtual sonography (RVS) allows displaying and synchronizing real-time US and multiplanar reconstruction of MRI images. The purpose of this study was to evaluate the feasibility and ability of RVS to assess adenomyosis since literature shows US itself has a reduced diagnostic accuracy compared to MRI. MATERIALS AND METHODS: This study was conducted over a 4-month period (March-June 2015). We enrolled in the study 52 women with clinical symptoms of dysmenorrhea, methrorragia and infertility. Every patient underwent an endovaginal US examination, followed by a 3T MRI exam and a RVS exam (Hitachi HI Vision Ascendus). The MRI image dataset acquired at the time of the examination was loaded into the fusion system and displayed together with the US images. Both sets of images were then manually synchronized and images were registered using multiple plane MR imaging. Radiologist was asked to report all three examinations separately. RESULTS: On a total of 52 patients, on standard endovaginal US, adenomyosis was detected in 27 cases: of these, 21 presented diffuse adenomyosis, and 6 cases focal form of adenomyosis. MRI detected adenomyosis in 30 cases: 22 of these appeared as diffuse form and 8 as focal form, such as adenomyoma and adenomyotic cyst, thus resulting in 3 misdiagnosed cases on US. RVS confirmed all 22 cases of diffuse adenomyosis and all 8 cases of focal adenomyosis. CONCLUSIONS: Thanks to information from both US and MRI, fusion imaging allows better identification of adenomyosis and could improve the performance of ultrasound operator thus to implement the contribution of TVUS in daily practice.

Burkitt's Lymphoma Presented as Advanced Ovarian Cancer without Evidence of Lymphadenopathy: CT and MRI Findings.

Burkitt's lymphoma is a rare non-Hodgkin's lymphoma which can occasionally involve the ovary and may cause confusion for the clinician since its presentation might mimic other much more frequent tumors. We present a case of a 23-year-old woman with sporadic Burkitt's lymphoma presented as advanced ovarian cancer with bilateral ovarian masses, peritoneal carcinomatosis, ascites, and marked elevation of CA-125. Liver involvement and atypical bone lesions, such as the cranial vault and the iliac wing, were also detected without evidence of lymphadenopathy. We describe the MRI and CT findings of simultaneous ovarian and bone lesions, which have never been reported in literature in a patient with Burkitt's lymphoma, before and after one cycle of chemotherapy. In evaluating any ovarian neoplasm in a young woman, Burkitt's lymphoma should be considered as a possibility, particularly if associated with bone lesions. MRI is the most useful tool to characterize the ovarian lesions and suggest the diagnosis before the histopathological results.

MRI and DWI: feasibility of DWI and ADC maps in the evaluation of placental changes during gestation.

OBJECTIVE: To establish if a correlation exists between apparent diffusion coefficient (ADC) values, obtained by diffusion-weighted imaging (DWI), and placental aging. METHOD: The study is divided into a retrospective phase and a prospective one.In the first phase, 145 pregnant women underwent fetal magnetic resonance imaging (MRI) for suspected disorders in several organs. We performed DWI (b value 0, 200 and 700 s/mm(2)) in all the fetuses, evaluating the patients in whom the whole placenta was visible.In the prospective phase, 50 women (52 fetuses) underwent MRI. We performed, in the same patient, two echo-planar sequences with b values of 0, 200 and 700, and 50, 200 and 700 s/mm(2), including the whole placenta.The ADC maps were calculated for all fetuses, divided into three groups based on gestational age (GA): group I: 20-26 weeks' gestation, II: 27-33, III: 34-40. RESULTS: In the retrospective phase, ADC values had a range from 1 to 2.4 mm(2)/s, showing a significant correlation between ADC values and GA.ADC values obtained by DWI with b value 0, 200 and 700 s/mm(2) had a range from 0.8 to 2.5 mm(2)/s, with an inverse correlation between ADC values and GA, whereas the ADC values with b value 50, 200 and 700 s/mm(2) did not show any statistical correlation (range: 1.5-1.7 mm(2)/s). CONCLUSION: DWI with ADC maps can not be considered markers for placental aging because they are affected by perfusional and circulatory motion.