The Value of Magnetic Resonance Diffusion-Weighted Imaging and Dynamic Contrast Enhancement in the Diagnosis and Prognosis of Treatment Response in Patients with Epithelial Serous Ovarian Cancer.

Background. The aim of our study was to describe the selected parameters of diffusion-weighted imaging (DWI) and perfusion dynamic contrast enhancement (DCE) MRI in primary tumors in patients with serous epithelial ovarian cancer (EOC), as well as in disease course prognosis and treatment response, including bevacizumab maintenance therapy. Materials and Methods. In total, 55 patients with primary serous EOC were enrolled in the study. All patients underwent MR imaging using a 1.5 T clinical whole-body MR system in preoperative DWI and DCE MRI selected parameters: apparent diffusion coefficients (ADC), time to peek (TTP) and perfusion maximum enhancement (Perf. Max. En.) were measured. The data were compared with histopathological and immunochemistry results (with Ki67 and VEGF expression) and clinical outcomes. Results. Higher mean ADC values were found in low-grade EOC compared to high-grade EOC: 1151.27 vs. 894,918 (p < 0.0001). A negative correlation was found between ADC and Ki67 expression (p = 0.027), and between ADC and VEGF expression (p = 0.042). There was a negative correlation between TTP and PFS (p = 0.0019) and Perf. Max. En. and PSF (p = 0.003). In the Kaplan−Meier analysis (log rank), a longer PFS was found in patients with ADC values greater than the median; p = 0.046. The Kaplan−Meier analysis showed a longer PFS (p = 0.0126) in a group with TTP below the mean value for this parameter in patients who received maintenance treatment with bevacizumab. Conclusions. The described relationships between PFS and DCE and DWI allow us to hope to include these parameters in the group of EOC prognostic factors. This aspect seems to be of particular interest in the case of the association of PFS with DCE values in the group of patients treated with bevacizumab.

Radiographic Measurement of Gastric Remnant Volume After Laparoscopic Sleeve Gastrectomy: Assessment of Reproducibility and Correlation with Weight Loss.

BACKGROUND: As a restrictive procedure, laparoscopic sleeve gastrectomy (LSG) relies primarily on the reduction of gastric volume. It has been suggested that an immediate postoperative gastric remnant volume (GRV) may influence long-term results of LSG; however, there are no consensus in this matter. The aim of this study was to assess the reproducibility of different radiographic methods of GRV calculation and evaluate their correlation with the weight loss (WL) after surgery. METHODS: This retrospective study evaluated 174 patients who underwent LSG in the period from 2014 to 2017. Using UGI, GRV was measured with 3 different mathematical methods by 2 radiologists. Intraobserver and interobserver calculations were made. Correlation between GRV and WL were estimated with calculations percentage of total weight loss (%TWL) and percentage of excess weight loss (%EWL) after 1, 3, 6, 12, 18, and 24 months postoperatively. RESULTS: During analysis of intraobserver similarities, the results of ICC calculation showed that reproducibility was good to excellent for all GRV calculation methods. The intraobserver reproducibility for Reader I was highest for cylinder and truncated cone formula and for Reader II for ellipsoid formula. The interobserver reproducibility was highest for ellipsoid formula. Regarding correlation between GRV and WL, significant negative correlation has been shown on the 12th month after LSG in %TWL and %EWL for every method of GRV calculation, most important for ellipsoid formula (%TWL - r(X,Y) = -0.335, p < 0.001 and %EWL - r(X,Y) = -0.373, p < 0.001). CONCLUSION: Radiographic methods of GRV calculation are characterized by good reproducibility and correlate with the postoperative WL.

Role of Diffusion Tensor Imaging Parameters in the Characterization and Differentiation of Infiltrating and Non-Infiltrating Spinal Cord Tumors : Preliminary Study.

BACKGROUND AND PURPOSE: Recent attempts to utilize diffusion tensor imaging (DTI) to identify the extent of microinfiltration of a tumor in the brain have been successful. It was therefore speculated that this technique could also be useful in the spinal cord. The aim of this study was to differentiate between infiltrating and noninfiltrating intramedullary spinal tumors using DTI-derived metrics. MATERIAL AND METHODS: The study group consisted of 6 patients with infiltrating and 12 with noninfiltrating spinal cord tumors. Conventional magnetic resonance imaging (MRI) with gadolinium administration was performed followed by DTI. Fractional anisotropy (FA), diffusivity (TRACE) and apparent diffusion coefficient (ADC) were measured in the enhancing tumor mass, peritumoral margins, peritumoral edema and normal appearing spinal cord. The results were compared using non-parametric Mann-Whitney U test with statistical significance p < 0.05. RESULTS: In peritumoral margins the FA values were significantly higher in the noninfiltrating compared to the infiltrating tumors (p < 0.007), whereas TRACE values were significantly lower (p < 0.017). The results were similar in peritumoral edema. The FA values in the tumor mass showed no significant differences between the two groups while TRACE showed a statistically significant difference (p < 0.003). There was no statistical difference in any parameters in normal appearing spinal cord. CONCLUSION: Quantitative analysis of DTI parameters of spinal cord tissue surroundings spinal masses can be useful for differentiation between infiltrating and non-infiltrating intramedullary spinal tumors.

Magnetic resonance diffusion-weighted imaging in diagnostics of primary fallopian tube carcinoma - is it useful?

PURPOSE: Primary fallopian tube carcinoma (PFTC) is the rarest form of female genital malignancy. The imaging applied for suspected adnexal masses includes transvaginal ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI), but the vast majority of PFTC is recognised intraoperatively. MATERIAL AND METHODS: The study group consisted of seven women with postoperatively histopathological diagnosis of PFTC. To recognise characteristic findings for PFTC, retrospective analysis of preoperative MRI was performed. All patients underwent MRI of the pelvis and abdomen using a 1.5T MR system. Based on the results of the above imaging, suspected adnexal masses were recognised. MRI protocol contained T2-weighted images, fat-suppressed T2-weighted, T2-TIRM, DW EPI, pre- and postcontrast dynamic 3D T1 GRE in transverse orientation, with diffusion weightings of 0, 50, 100, 150, 200, 400, 800, and 1200 s/mm2. Regions of interest were outlined by a radiologist, who documented the character of adnexal masses on diffusion-weighted (DW) images and apparent diffusion coefficient (ADC) maps. RESULTS: In all seven patients with PFTC unilateral tumour was found. On all DW images (with ß values of 0, 50, 100, 150, 200, 400, 800, and 1200 s/mm2) the mean signal intensities of solid parts of tumour were significantly higher than the mean signal intensities of normal ovarian tissue (p = 0.0001). There were no statistically significant differences between eight ß values applied for ADC calculations. CONCLUSIONS: Preoperative diagnostics of PFTC is difficult and mainly based on morphological features. Previous research did not show characteristics of PFTC in post-contrast dynamic imaging. In our material a clear increasing of signal intensity in DW imaging occurred independently of the ß value.

Diffusion-Weighted Imaging of Small Peritoneal Implants in "Potentially" Early-Stage Ovarian Cancer.

INTRODUCTION: MRI is established modality for the diagnosis of ovarian malignancies. Advances in MRI technology, including DW imaging, could lead to the further increase in the sensitivity of MRI for the detection of peritoneal metastases. The aim of this study was to assess the accuracy of DW imaging for detection of peritoneal metastatic disease in patients suspected of having potentially early ovarian cancer and secondly to evaluate ADC values of peritoneal implants. MATERIALS AND METHODS: The prospective study group consisted of 26 women with sonographic or/and CT diagnosis of suspected ovarian tumor. Based on the results of the above imaging, in none of them was extraovarian spread of disease or ascites recognized. All patients underwent MRI with DW imaging. RESULTS: Overall, 18 extraovarian peritoneal lesions were found on DW images in 10 from 26 examined patients. All implants had diameter ≤10 mm. The presence of all lesions diagnosed by MRI was confirmed intraoperatively. Histopathologic findings in 17 proofs confirmed ovarian cancer. PPV was 94%. On all DW images (with b values of 0, 50, 100, 150, 200, 400, 800, and 1200 s/mm(2)) the mean signal intensities of peritoneal lesions were significantly higher than the mean signal intensities of normal adjacent tissue (p = 0.000001).

Gd-EOB-DTPA-Enhanced MR Imaging of the Liver: The Effect on T2 Relaxation Times and Apparent Diffusion Coefficient (ADC).

BACKGROUND: To investigate the effect of gadoxetic acid disodium (Gd-EOB-DTPA) on T2 relaxation times and apparent diffusion coefficient (ADC) values of the liver and focal liver lesions on a 1.5-T system. MATERIAL/METHODS: Magnetic resonance (MR) studies of 50 patients with 35 liver lesions were retrospectively analyzed. All examinations were performed at 1.5T and included T2-weighted turbo spin-echo (TSE) and diffusion-weighted (DW) images acquired before and after intravenous administration of Gd-EOB-DTPA. To assess the effect of this hepatobiliary contrast agent on T2-weighted TSE images and DW images T2 relaxation times and ADC values of the liver and FLLs were calculated and compared pre- and post-injection. RESULTS: The mean T2 relaxation times of the liver and focal hepatic lesions were lower on enhanced than on unenhanced T2-weighted TSE images (decrease of 2.7% and 3.6% respectively), although these differences were not statistically significant. The mean ADC values of the liver showed statistically significant decrease (of 4.6%) on contrast-enhanced DW images, compared to unenhanced images (P>0.05). The mean ADC value of liver lesions was lower on enhanced than on unenhanced DW images, but this difference (of 2.9%) did not reach statistical significance. CONCLUSIONS: The mean T2 relaxation times of the liver and focal liver lesions as well as the mean ADC values of liver lesions were not significantly different before and after administration of Gd-EOB-DTPA. Therefore, acquisition of T2-weighted and DW images between the dynamic contrast-enhanced examination and hepatobiliary phase is feasible and time-saving.

Characterization of focal liver lesions using quantitative techniques: comparison of apparent diffusion coefficient values and T2 relaxation times.

OBJECTIVES: To compare the efficacy of two quantitative methods for discrimination between benign and malignant focal liver lesions (FLLs): apparent diffusion coefficient (ADC) values and T2 relaxation times. METHODS: Seventy-three patients with 215 confirmed FLLs (115 benign, 100 malignant) underwent 1.5-T MRI with respiratory-triggered single-shot SE DWI (b = 50, 400, 800) and dual-echo T2TSE (TR = 3,000 ms; TE1 = 84 ms; TE2 = 228 ms). ADC values and T2 relaxation times of FLLs were calculated. Sensitivity, specificity and accuracy of both techniques in diagnosing malignancy were assessed. RESULTS: The mean ADC value of malignant tumours (1.07 × 10(-3) mm(2)/s) was significantly lower (P < 0.05) than that of benign lesions (1.86 × 10(-3) mm(2)/s ); however, with the use of the optimal cut-off value of 1.25 × 10(-3) mm(2)/s, 20 false positive (FP) and 20 false negative (FN) diagnoses of malignancy were noted, generating 79 % sensitivity, 82.6 % specificity and 80.9 % accuracy. The mean T2 relaxation time of malignant tumours (64.4 ms) was significantly lower (P < 0.05) than that of benign lesions (476.1 ms). At the threshold of 107 ms 22 FP and 1 FN diagnoses were noted; the sensitivity was 99 %, specificity 80.9 % and accuracy 89.3 %. CONCLUSIONS: Quantitative analysis of T2 relaxation times yielded significantly higher sensitivity and accuracy in diagnosing malignant liver tumour than ADC values. KEY POINTS: • Diffusion-weighted magnetic resonance imaging is increasingly used for liver lesions. • But ADC values demonstrated only moderate accuracy for differentiation of liver lesions. • T2 relaxation times yielded higher accuracy in diagnosing malignant liver tumours. • Both ADC and T2 values overlapped between focal nodular hyperplasia and malignant lesions. • Nevertheless T2 liver mapping could be valuable for evaluating focal liver lesions.

Sex hormone patterns in women with multiple sclerosis as related to disease activity--a pilot study.

BACKGROUND AND PURPOSE: The influence of sex hormones on immune system activity in multiple sclerosis (MS) has been suggested by clinical evidence. The aim of the study was to ana-lyse the pattern of sex hormones in MS women and to correlate the hormone pattern abnormalities to the disease course as well as to the magnetic resonance imaging (MRI) results. MATERIAL AND METHODS: We studied the serum level of the progesterone, ß-oestradiol and prolactin in 46 women with clinical definite MS aged from 19 to 65; mean disease duration was 11.80 ± 9.86 years. The evaluation of the intensity of hormonal changes was done using a scoring system (0-3). On the brain MRI, the presence of brain atrophy, of hypothalamic demyelination as well as demyelination intensity (or degree) were analysed. The evaluation of the degree of demyelination and brain atrophy was done using a scoring system (0-4). RESULTS: The main hormonal abnormalities consisted of decreased progesterone level, increased oestradiol level or both. The sex hormone pattern was abnormal in 56% of patients. Hypothalamic lesions were found on MRI in 53% of cases. The abnormal hormonal pattern correlated with intensity of MR changes (p < 0.05, Fisher's exact test), but neither with presence of hypothalamic changes nor with disease parameters (Expanded Disability Status Scale, relapse rate, disease duration). CONCLUSIONS: It is important to check the hormonal pattern in MS women because according to our results it may be related to the disease activity and probably affects the type of therapeutic intervention. This pilot study will be extended in a larger population.

Spectral changes in postoperative MRS in high-grade gliomas and their effect on patient prognosis.

The aim of the study was to find differences in magnetic resonance spectroscopy (MRS) which might facilitate differential diagnosis between tumour regrowth and a remnant tumour with present postradiation changes or postradiation necrosis in the vicinity of the postoperative bed, based on the assessment of the dynamics between two MRS, i.e. preoperative and postoperative scanning, performed at 6 months after surgery. Therefore, in 9 patients with high-grade gliomas, MRS spectra were obtained. Subsequently, a partial tumour resection was done in 5 patients, and 4 subjects underwent a gross total resection. On the second MRS the voxel was placed on an observed contrast enhancement area. The tumour regrowth onset was established by comparing the results of control MRI with postoperative CT scans, and also on the basis of changes in clinical condition as well as a further follow-up, including MRI studies. In patients with tumour regrowth Cho/NAA and Lac/Cr ratios increased and the NAA/Cr ratio decreased between the two MRS studies; in the patients without regrowth, the ratio changes were inverse. In both groups, a decrease in Cho/Cr ratio was observed. In a univariate analysis the presence of tumour regrowth and an increase in Cho/NAA ratio between the two MRS were correlated with a shorter further survival time; a tendency to shorter further survival time was noted with decrease in NAA/Cr ratio. In conclusion, MRS is a diagnostic tool which, on the basis of direction of changes in the value of metabolite ratios, helps additionally confirm the diagnosis of glioma regrowth. In the case of a visible contrast enhancement area on the postoperative MRI with observed concomitant increase in Cho/NAA ratio and decrease in NAA/Cr ratio between pre- and postoperative MRS examinations, preliminary suspicion should be that of glioma regrowth rather than of remnant tumour after surgery or postradiation lesions.

Discrimination of benign from malignant hepatic lesions based on their T2-relaxation times calculated from moderately T2-weighted turbo SE sequence.

The differentiation of hemangioma from other hepatic neoplasms using MRI usually relies on the evaluation of heavily T2-weighted images. The aim of this study was to assess the value of T2-relaxation times calculated from moderately T2-weighted turbo spin-echo (TSE) sequence in characterization of focal hepatic lesions, including hepatic malignancies, focal nodular hyperplasia (FNH), hemangioma, and cyst. Fifty-two patients with 114 proven lesions (61 malignant masses, 6 focal nodular hyperplasias, 28 hemangiomas, 19 cystic lesions) were examined on 1.5-T system using a double-echo TSE sequence (TR=1800 ms; TE(eff) 1=40 ms; TE(eff) 2=120 ms). Signal intensities (SI) of the liver as well as SI of all lesions were measured, and then the T2-relaxation times were calculated. The mean T2 time for the liver was 54 ms (+/-8 ms), for FNH 66 ms (+/-7 ms), for malignant hepatic lesions 85 ms (+/-17 ms), for hemangiomas 155 ms (+/-35 ms), and for cystic lesions 583 ms (+/-369) ms. Most malignant hepatic lesions were best differentiated between the thresholds of 67 and 116 ms, generating a sensitivity of 90% and a specificity of 94%. There were six false-negative diagnoses of malignant tumor and three false-positive cases (two hemangiomas and one FNH). Calculation of the T2-relaxation times obtained from the double-echo TSE sequence with moderate T2-weighting allowed differentiation between malignant and benign hepatic lesions with high sensitivity and specificity.