Chiara Zuiani

Primary Motor and Sensory Cortex Activation during Motor Performance and Motor Imagery: A Functional Magnetic Resonance Imaging Study

The intensity and spatial distribution of functional activation in the left precentral and postcentral gyri during actual motor performance (MP) and mental representation [motor imagery (MI)] of self-paced finger-to-thumb opposition movements of the dominant hand were investigated in fourteen right-handed volunteers by functional magnetic resonance imaging (fMRI) techniques. Significant increases in mean normalized fMRI signal intensities over values obtained during the control (visual imagery) tasks were found in a region including the anterior bank and crown of the central sulcus, the presumed site of the primary motor cortex, during both MP (mean percentage increase, 2.1%) and MI (0.8%). In the anterior portion of the precentral gyrus and the postcentral gyrus, mean functional activity levels were also increased during both conditions (MP, 1.7 and 1.2%; MI, 0.6 and 0.4%, respectively). To locate activated foci during MI, MP, or both conditions, the time course of the signal intensities of pixels lying in the precentral or postcentral gyrus was plotted against single-step or double-step waveforms, where the steps of the waveform corresponded to different tasks. Pixels significantly (r > 0.7) activated during both MP and MI were identified in each region in the majority of subjects; percentage increases in signal intensity during MI were on average 30% as great as increases during MP. The pixels activated during both MP and MI appear to represent a large fraction of the whole population activated during MP. These results support the hypothesis that MI and MP involve overlapping neural networks in perirolandic cortical areas.

Multicenter surveillance of women at high genetic breast cancer risk using mammography, ultrasonography, and contrast-enhanced magnetic resonance imaging (the high breast cancer risk italian 1 study): final results.

Objectives:To prospectively compare clinical breast examination, mammography, ultrasonography, and contrast-enhanced magnetic resonance imaging (MRI) in a multicenter surveillance of high-risk women. Materials and Methods:We enrolled asymptomatic women aged ≥25: BRCA mutation carriers; first-degree relatives of BRCA mutation carriers, and women with strong family history of breast/ovarian cancer, including those with previous personal breast cancer. Results:A total of 18 centers enrolled 501 women and performed 1592 rounds (3.2 rounds/woman). Forty-nine screen-detected and 3 interval cancers were diagnosed: 44 invasive, 8 ductal carcinoma in situ; only 4 pT2 stage; 32 G3 grade. Of 39 patients explored for nodal status, 28 (72%) were negative. Incidence per year-woman resulted 3.3% overall, 2.1% <50, and 5.4% ≥50 years (P < 0.001), 4.3% in women with previous personal breast cancer and 2.5% in those without (P = 0.045). MRI was more sensitive (91%) than clinical breast examination (18%), mammography (50%), ultrasonography (52%), or mammography plus ultrasonography (63%) (P < 0.001). Specificity ranged 96% to 99%, positive predictive value 53% to 71%, positive likelihood ratio 24 to 52 (P not significant). MRI showed significantly better negative predictive value (99.6) and negative likelihood ratio (0.09) than those of the other modalities. At receiver operating characteristic analysis, the area under the curve of MRI (0.97) was significantly higher than that of mammography (0.83) or ultrasonography (0.82) and not significantly increased when MRI was combined with mammography and/or ultrasonography. Of 52 cancers, 16 (31%) were diagnosed only by MRI, 8 of 21 (38%) in women <50, and 8 of 31 (26%) in women ≥50 years of age. Conclusion:MRI largely outperformed mammography, ultrasonography, and their combination for screening high-risk women below and over 50.

Locally advanced breast cancer: comparison of mammography, sonography and MR imaging in evaluation of residual disease in women receiving neoadjuvant chemotherapy

The accuracy of mammography, sonography and magnetic resonance imaging (MRI) in identifying residual disease after neoadjuvant chemotherapy is evaluated and imaging findings are correlated with pathologic findings. Fifteen patients enrolled in an experimental protocol of preoperative neoadjuvant chemotherapy underwent clinical examination, mammography, sonography and dynamic MRI, performed in this order, before and respectively after 2 and 4 cycles of neoadjuvant chemotherapy. Four radiologists, two for mammography, one for sonography and one for MR, examined the images, blinded to the results of the other examinations. All patients underwent radical or conservative surgery, and imaging findings were compared with pathologic findings. MRI identified 2/15 (13.3.%) clinically complete response (CR), 9/15 (60%) partial response (PR), 3/15 (20%) stable disease (SD) and 1/15 (6.7%) progressive disease. Mammography identified 1/15 (6.7%) clinically CR, 8/15 (53.3%) PR and 4/15 (27%) SD, and was not able to evaluate the disease in 2/15 (13%) cases. Sonography presented the same results as MRI. Therefore, MRI and sonography compared to mammography correctly identified residual disease in 100 vs. 86%. MRI resulted in two false-negative results because of the presence of microfoci of in situ ductal carcinoma (DCIS) and invasive lobular carcinoma (LCI). MRI was superior to mammography in cases of multifocal or multicentric disease (83 vs. 33%). Sonography performed after MRI improves the accuracy in evaluation of uncertain foci of multifocal disease seen on MR images with an increase of diagnostic accuracy from 73 to 84.5%. MRI assesses response to neoadjuvant chemotherapy better than traditional methods of physical examination and mammography.

Contrast-Enhanced Breast MRI in Patients with Suspicious Microcalcifications on Mammography: Results of a Multicenter Trial

OBJECTIVE The objective of our study was to test dynamic MRI in evaluating mammographically detected suspicious microcalcifications. MATERIALS AND METHODS One hundred twelve patients with mammographically detected microcalcifications with BI-RADS category 5 (n = 78) or 4 (n = 34) lesions were studied at 17 centers a using 3D gradient-echo dynamic coronal technique (< or = 3 mm thickness) and 0.1 mmol/kg of gadoteridol. A pathologic sample was obtained in all cases. Agreement between the major diameter measured on mammography, MRI, or both and the major diameter measured at pathologic examination was calculated in 62 cases. RESULTS Of the 112 lesions, pathologic examination revealed 37 benign lesions, 33 ductal carcinoma in situ (DCIS), and 42 invasive carcinomas. The specificity of MRI for benign lesions was 68%. Considering the subgroups of calcifications alone and calcifications associated with masses, the specificity values became 79% and 33%, respectively. The sensitivity of MRI for DCIS was 79%. Analysis of the two subgroups showed sensitivity values of 68% for calcifications alone and of 1% for calcifications associated with masses. The sensitivity for invasive carcinomas was 93%. Analysis of the two subgroups showed sensitivity values to be 92% for calcifications alone and 94% for calcifications associated with masses. Considering the overall results, the sensitivity of MRI was 87%; specificity, 68%; positive predictive value, 84%; negative predictive value, 71%; and accuracy, 80%. Considering the subgroups of calcifications alone and calcifications associated with masses, the sensitivity values became 80% and 97%; the positive predictive values, 86% and 82%; the negative predictive values, 71% and 75% (95% confidence interval [CI], 0.19-0.99); and the accuracy values, 80% and 82% (95% CI, 0.66-0.92), respectively. An odds ratio (OR) of 13.54 (95% CI, 5.20-35.28) showed a raised risk of malignant breast tumor in subjects with positive MR examination of mammographically detected suspicious clusters of microcalcifications. The statistical analysis on each subgroup showed an OR of 15.07 (95% CI, 4.73-48.08) for calcifications alone and an OR of 14.00 (95% CI, 1.23-158.84) for calcifications associated with masses. Any significant improvement in the predictive ability of dynamic MRI depending on the extent of calcifications on mammography was not proved. Considering the 62 cases of proved malignancy with measured maximal diameter at pathologic examination, both mammography and MR examination seem to overestimate tumor extent. CONCLUSION The not-perfect sensitivity of MRI (87%), when applying our interpretation criteria and imaging sequences, is a crucial point that prevents us from clinical use of MRI in the diagnosis of mammographically detected microcalcifications.

Relevance of b‐values in evaluating liver fibrosis: A study in healthy and cirrhotic subjects using two single‐shot spin‐echo echo‐planar diffusion‐weighted sequences

To investigate the relevance of increasing b‐values in evaluating liver fibrosis through the agreement of two diffusion‐weighted (DW) sequences.

Diffusion-weighted MRI in evaluating liver fibrosis: a feasibility study in cirrhotic patients.

AbstractPurpose.This study was designed to establish whether the measurement of apparent diffusion coefficients (ADCs) is clinically accurate in diagnosing liver fibrosis in a selected series of cirrhotic patients.Materials and methods.Twenty-eight cirrhotic patients (mean age 58.1 years) with histologically proven liver fibrosis and 29 healthy controls (mean age 43.8 yeas) underwent liver diffusion-weighted magnetic resonance (MR) using a 1.5-Tesla (T) magnet equipped with a phased-array coil. Diffusion studies with parallel imaging [generalized autocalibrating partially parallel acquisitions (GRAPPA)] were performed within a single breath-hold using a single-shot spin-echo echo-planar sequence (TE 74 ms) using four b values: b=0, 150, 250 and 400 s/mm2. A unidirectional diffusion gradient was applied. ADCs were measured on ADC maps.Results.Mean ADC was significantly lower in cirrhotic livers than in controls (1.11±0.16 vs. 1.54±0.12.10-3mm2/s) (p<0.0001). Receiver operating characteristic (ROC) analysis showed an area under the curve (AUC) of 0.96 [confidence interval (CI) 95%:(0.87; 0.94)], demonstrating higher sensitivity and specificity (92.9% and 100%, respectively) for an ADC cutoff of 1.31.10-3mm2/s. Positive predictive value (PPV), negative predictive value (NPV) and overall accuracy were 100%, 99.9% and 96.4%, respectively.Conclusions.Diffusion-weighted MRI is an accurate tool in evaluating advanced liver fibrosis if an optimised single-shot spinecho echo-planar sequence with maximum intermediate b value is used. The ADC threshold for liver fibrosis was 1.31.10-3mm2/s.

Role of Mammography, Ultrasound and Large Core Biopsy in the Diagnostic Evaluation of Papillary Breast Lesions

Background: It is well recognized that distinguishing benign from malignant papillary lesions of the breast may pose challenging diagnostic problems. To prospectively evaluate the potential role of mammography, ultrasound and image-guided core biopsy in the diagnosis of papillary lesions of the breast. Methods: 1,442 women consecutively underwent 14-gauge core biopsy and in 51 cases (3.5%) a diagnosis of papillary lesion was formulated. Both radiologists and pathologists independently expressed their degree of suspicion of malignancy (not suspicious, low, moderate, high) on the basis of radiological and core biopsy findings, respectively. Surgical excision of the lesion was used as gold standard and diagnostic agreement was assessed by the kappa statistic. Results: At surgery, 19 of the 49 (38.7%) resected cases had a diagnosis of malignancy. A poor agreement was found between mammography and core biopsy results in the categorization of suspicion of malignancy (k = 0.03). Similar data were obtained between ultrasound and core biopsy (k = 0.07). A poor agreement was also observed between radiological and surgical results (k < 0.20). In contrast, a good agreement was found between core biopsy and surgical samples (k > 0.70). However, 5 (26%) out of the 19 malignant cases at surgery were judged as benign or probably benign on core biopsy. Depending on how the categories of suspicion on core biopsy were set up, the range of sensitivity was 74–89%, whereas specificity ranged from 91 to 97%. Conclusions: Image-guided large core biopsy allows for a correct diagnosis in the majority of papillary lesions. However, its sensitivity is not good enough for surgical excision to be avoided.

MRI scoring system including dynamic motility evaluation in assessing the activity of Crohn's disease of the terminal ileum

RATIONALE AND OBJECTIVES We sought to investigate the value of a MRI scoring system including dynamic motility evaluation in the assessment of small bowel Crohns disease activity. MATERIALS AND METHODS From March 2005 to December 2006, 52 patients with suspected Crohns disease onset or relapse underwent MRI on a 1.5-T magnet. Bowel distention was achieved orally assuming a mean of 1.6 L of a polyethyleneglycol (PEG) preparation. Per-patient assessment of disease activity was based on a scoring system including evaluation of morphology and motility of the small bowel and perivisceral structures (true-FISP, cine-true-FISP, and HASTE T2W sequences) and dynamic assessment of parietal contrast enhancement (FLASH T1W sequence). Patients were included in three categories, using endoscopic biopsy as the standard reference: no activity/quiescent disease, mild activity, or moderate-to-severe activity. Patients without terminal ileum involvement were excluded from data analysis. RESULTS MRI allowed a detailed and panoramic evaluation of the small bowel in all subjects examined. MRI properly assessed 14 of 16 (87.5%) cases of no activity/quiescent disease, 12 of 14 (85.7%) cases of mild activity, and 15 of 15 (100%) cases of severe activity. Overall, activity score led to a per-patient misdiagnosis of disease activity in a nonsignificant proportion of subjects (4 of 45; 8.8%) (P > .05), determining two false-positive and two false-negative results of mild disease activity. Sensitivity, specificity, PPV, NPV, and overall accuracy in assessing disease activity were 93.1%, 87.5%, 93.1%, 87.5%, and 91.1%, respectively. CONCLUSION Accurate assessment of Crohns disease activity is achieved by using an activity score providing an overall interpretation of MRI findings.

Incidental pancreatic cysts on 3D turbo spin echo magnetic resonance cholangiopancreatography: prevalence and relation with clinical and imaging features

PurposeTo estimate the prevalence of incidental pancreatic cysts (IPCs) in asymptomatic patients addressed to magnetic resonance cholangiopancreatography (MRCP), and to correlate it with clinical and imaging features.Materials and methodsMagnetic resonance cholangiopancreatography performed over 26-months on 152 patients with unsuspected/unknown pancreatic disease were reviewed to assess IPCs’ features of presentation. Multivariate analysis was performed to evaluate the correlation of IPCs with clinical information and type of pancreaticobiliary findings at MRCP.ResultsPrevalence of IPCs was 44.7%. Cysts sized 3–24 mm (mean, 6.08 mm), and were ≤4 in number in 83.8% of patients. Based on number, dimensions and relation with the main pancreatic duct, IPCs presented with intraductal-papillary-mucinous neoplasm (IPMN)-like or indeterminate patterns in 31.7% and 13.1% of patients, respectively. At follow-up on 24 patients, no evolution was found, except in one patient with proven IPMN showing increase in cysts number and dimensions (evolution rate of 4.1%). Features correlating with IPCs were age ≥60 years old, and history of autoimmune hepatobiliary disease, showing odds ratios of 5.95 (95% CI 2.77–12.79) and 0.13 (95% CI 0.04–0.44), respectively.ConclusionsIncidental pancreatic cysts represent a frequent finding at MRCP, correlating positively with increasing age, and negatively with biliary autoimmune disease. Cysts more frequently present with IPMN-like pattern.

Large core biopsy for diagnostic and prognostic evaluation of invasive breast carcinomas

Large core biopsy is a recently introduced method for pre-operative evaluation of breast lumps. The aim of this study was to evaluate the usefulness of this technique in providing pre-operative diagnostic and prognostic information that can lead to a correct line of treatment. We compared 41 cases of breast carcinomas diagnosed both by core biopsies and surgically removed samples. A high (93%) diagnostic agreement was obtained. Moreover, we found a significant correlation for mitotic count (r = 0.76), oestrogen receptor (r = 0.78), progesterone receptor (r = 0.80), p53 (r = 0.86) and c-erbB-2 (r = 0.90) analysis between core biopsy and definitive surgical pathology. An agreement for histological grading evaluation between the two techniques was obtained in 32 out of 40 cases (k = 0.65) whereas in the other cases, a lower grade was assigned by evaluating core biopsies. These findings suggest that percutaneous core breast biopsy is a valid tool for pre-operative management of breast lesions, but this should be confirmed in larger, prospective studies.