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The aim of our study was to test the possibility of using image subtraction in detecting enhancing lesions in brain MR scans with and without magnetization transfer (MT) in multiple sclerosis (MS). Ten MS patients underwent 1.5-T MR imaging of the brain with spin-echo T1-weighted sequences with and without MT, repeated after 0.1 mmol/kg of an usual two-compartment paramagnetic contrast agent (Gadoteridol, Gd-HP-DO3A). Precontrast images were subtracted from postcontrast. Enhancing lesions were counted on the postcontrast images only (post-Gd), comparing pre- and postcontrast images by direct visual control (pre/post-Gd), and on the subtracted images (SI) only. Without MT, 36 enhancing lesions were counted on post-Gd, 36 on pre/post-Gd, and 59 on SI; using MT, 69, 52, and 50, respectively. Significant differences were found for pre/post-Gd without MT vs SI without MT ( p=0.028) and vs pre/post-Gd with MT ( p=0.012) as well as for pre/post-Gd with MT vs post-Gd with MT ( p=0.028). With pre/post-Gd, MT allowed the detection of 1.6 enhancing lesions per patient more than without MT. Whereas the SI without MT allow the detection of an increased number of enhancing lesions, SI with MT do not. An off-site final assessment allowed calculation of sensitivity and positive predictive value as follows: without MT were 63 and 94% (post-Gd), 67 and 100% (pre/post-Gd), 96 and 88% (SI); and with MT were 93 and 73% (post-Gd), 96 and 100% (pre/post-Gd), 91 and 98% (SI), respectively. Thus, SI seem to increase the sensitivity without MT; moreover, they could be used to correct the pseudoenhancement that impair post-Gd images with MT. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the value of the early phase of MR enhancement of breast lesions., Method: To study 63 breast lesions (size 5-45 mm in diameter) in 56 patients, whole-breast and lesion-targeted precontrast T1 -weighted gradient-echo 2D sequences were acquired. After intravenous injection of Gd-DTPA (0.1 mmol/Kg), four targeted scans, each every 15 seconds during the first minute (1-m), and seven whole-breast scans, each every minute up to 8 minutes (8-m), were performed. The subtraction technique was used, and percent enhancement curves were obtained. The final diagnosis was obtained by histology for 36 lesions, including 28 malignancies, and by fine-needle aspiration cytology and at least 1-year negative follow-up for the remaining 27 benign lesions., Results: Significant differences in enhancement between malignant and benign lesions were found using both techniques (p<0.0001). However the ratio between the median enhancement of malignant lesions and that of benign lesions was 6.7 (15 s), 4.8 (30 s), 4.6 (45 s), and 3.8 (60 s), descending from 4.3 to 2.5 from the second to the eighth minute. The overlap between the malignant and benign curves was 9% of the malignant range with the 1-m technique, and 50% with the 8-m technique. Three blinded observers obtained a 100% sensitivity with both techniques and a specificity of 94-97% with the 1-m technique and 83-89% with the 8-m technique., Conclusion: The first minute of Gd-enhancement allows a more prominent differentiation between malignant and benign breast lesions than the following times.

We reevaluated the magnetic resonance (MR) examinations of 38 healthy volunteers (control group, CG) and of 124 patients with RV arrhythmia with left bundle branch block (LBBB) morphology: 45 with episodes of RV sustained tachycardia and of polymorphic RV premature beats (RVST-PPB group); 36 with only RV outflow tract sustained or not sustained tachycardia (RVOTT group); 43 with RV monomorphic premature beats (RVMPB group). All the examinations were reevaluated in a blinded fashion for detecting myocardial adipose replacement (AR) and wall bulges or aneurysms. In RVST-PPB patients, no AR was observed in 9%; 1 RV region involvement, 0%; 2 regions, 4%; > or = 3 regions, 87%; left ventricle (LV), 15%. RVOTT patients: 28%, 53%, 14%, 5%, and 0% [corrected], respectively. RVMPB patients: 33%, 46%, 19%, 2%, and 0% [corrected], respectively. In CG, AR was observed in 11% (in RV outflow tract), RV bulges were detected in 75% [corrected] of RVST-PPB, 39% of RVOTT, and 14% of RVMPB patients, none of the CG; RV aneurysms in 33% of RVST-PPB patients, none of RVOTT patients, RVMBP patients, and CG. A significant difference among groups for RV and LV AR as well as RV bulges and aneurysms was found (p < 0.0001). In the direct comparisons, significant differences were found for: disease duration (RVST-PPB vs. RVMPB, p = 0.0396); RV AR (all the patients groups vs. CG, RVST-PPB vs. RVOTT or RVMPB, p < 0.0001); RV aneurysms (RVST-PPB vs. CG, RVST-PPB vs. RVOTT or RVMPB, p < 0.0002); bulges (all comparisons, p < 0.0174). AR is confirmed as a structural substrate in RV arrhythmias. Number and extension of MR abnormalities are correlated to different degrees of RV arrhythmias.

Purpose: To evaluate lesion contrast enhancement in brain magnetic resonance (MR) images with and without magnetization transfer pulse (MT) in patients affected with multiple sclerosis (MS)., Material and Methods: Ten patients affected with relapsing-remitting MS underwent a 1.5-T (Magnetom Vision, Siemens) MR examination with T1-weighted spin-echo sequences without MT (TR/TE = 630/14 ms) and with MT (840/14 ms) using the following common parameters: 21 para-axial slices (thickness 5 mm, 10% gap); matrix 256 x 256; field of view 25 cm (rectangular 5/8); 2 excitations. The postcontrast sequences with and without MT were acquired in a randomized order, starting 5 minutes after the intravenous injection of 0.1 mmol/kg Gadoteridol (ProHance, Bracco). The images were blindly evaluated in four separate sessions: only the postcontrast images with MT (post-Gd with MT); only the postcontrast images without MT (post-Gd without MT); comparing the pre- and postcontrast images with MT (pre/post-Gd with MT); comparing the pre- and postcontrast images without MT (pre/post-Gd without MT). The number of hyperintense areas referred to contrast enhancement and the evaluation time were measured for each session. The Wilcoxon test was used for statistical analysis., Results: The number of areas referred to lesion contrast enhancement per patient were as follows: post-Gd with MT, 6.9 +/- 6.8 (mean +/- standard deviation) (range 1-24); post-Gd without MT, 3.6 +/- 4.3 (0-14); pre/post-Gd with MT, 5.2 +/- 6.1 (1-21); pre/post-Gd without MT, 3.6 +/- 4.9 (0-16). A nonsignificant difference was found for the comparison between post-Gd without MT and pre/post-Gd without MT while significant differences were found between post-Gd with MT and pre/post-Gd with MT (p = .028), pre/post-Gd without MT and pre/post-Gd with MT (p = .012), as well as between post-Gd without and post-Gd with MT (p = .008). The mean evaluation time for the different sessions was always less than a minute, ranging from 33 seconds for pre/post-Gd without MT to 51 seconds for post-Gd with MT., Conclusions: The postcontrast sequence obtained with the MT pulse detects more active lesions than the postcontrast sequence without MT. However, the comparison with the plain images with the MT pulse is mandatory to exclude pseudoenhancement foci, i.e. hyperintense areas already present in the precontrast images with the MT pulse, without disruption of the blood-brain barrier. The post-Gd without MT sequence needs not be compared with the precontrast images without MT. Differences in evaluation time are practically negligible.

Aim: Poor mucosal coating, due to excess of fluid in the colon lumen, is a problem when the oral lavage method (4 litres of an iso-osmotic saline solution containing polyethylene glycol) is used as a preparation for double-contrast barium enema. Our aim was to assess the value of prior administration of sennosides to obtain a clean colon with a reduced volume of polyethylene glycol (PEG)-saline solution, but maintaining good mucosal coating., Materials and Methods: After a 2-day low-residue diet, three different oral preparations were compared: (i) 4 litres of a PEG-saline solution (SELG) and 15 mg of bisacodyl (116 patients, SELG-4 group); (ii) 156 mg of sennosides, 15 g of magnesium sulphate, and 2 litres of water (116 patients, SennMg group); (iii) 156mg of sennosides and 2 litres of SELG (116 patients, SennSELG group). Compliance, complaints, cleansing, mucosal coating, and fluid retention were evaluated., Results: Compliance was > 94% in every group. A higher percentage of mild nausea was observed in SELG-4 group, of mild abdominal cramping in SennMg group, of substantial abdominal cramping in SennSELG group (P < 0.02). Cleansing was better in SennSELG than in both the SELG-4 (P = 0.0003) and SennMg (P = 0.0353) group. Mucosal coating was better in SennMg than both SELG-4 (P = 0.0034) and SennSELG (P < 0.0001) group. There was more residual fluid in the SennSELG group than both in SELG-4 (P = 0.0029) and SennMg (P = 0.0059) group., Conclusion: For colon cleansing, the combination of sennosides and PEG-saline solution was better than either the 4 litre PEG protocol or the combination of sennosides and magnesium sulphate. For mucosal coating, the protocol combining sennosides and magnesium sulphate was more effective than either protocols using the PEG-saline solution. This may be due to the interaction of residual magnesium ions in the colon lumen with the barium suspension.

Purpose: The purpose of this work was to compare Gd-enhanced breath-hold fast imaging with steady-state precession (Gd-FISP) with unenhanced time-of-flight (TOF) sequences in evaluating internal carotid arteries (ICAs)., Method: Thirty patients underwent three unenhanced TOF sequences [2D traveling saturation (Travelsat); 3D tilted optimized nonsaturated excitation (TONE); TOF 3D Multislab] and two breath-hold 3D Gd-FISP sequences with automated intravenous contrast agent injection (axial and coronal). ICAs were classified as normal (no stenosis); with mild (<30%), moderate (30-70%), or severe stenosis; or occluded (100%). Digital subtraction angiography (DSA) with aortic arch injection was used as a reference technique., Results: DSA revealed 20 normal ICAs; 11 mild, 9 moderate, and 14 severe stenoses; and 2 occlusions. DSA and all MR angiography (MRA) sequences diagnosed the occlusion of four common carotid arteries. The TOF 2D overestimated 10 stenoses, TOF 3D TONE 9, and TOF 3D Multislab 5; Gd-FISP 3D overestimated only 2 of them, reaching the highest sensitivity and specificity for severe stenoses. Significant differences were found between the overestimation of Gd-FISP and each of the three unenhanced sequences (0.0020 < p < 0.0313, Wilcoxon and McNemar tests). Severe artifacts were observed with TOF techniques only., Conclusion: Gd-FISP is an interesting, largely artifact-free improvement for MRA of ICAs.

Magnetic resonance (MR) imaging was used to evaluate the effect of ultrasound-guided percutaneous ethanol injection (PEI) of autonomous thyroid nodules (ATNs). Nine patients affected with ATN (3.7-32.2 mL volume) underwent PEI (4-19 mL ethanol, subdivided in 3-6 weekly procedures). MR imaging (1.5 T) was performed before each alcoholization and 1 month after the last PEI procedure with the following parameters: T1- (550/12) and T2-weighted (2200/160) spin-echo images; 4-mm slices, 10% gap; coronal planes. A further seven patients with normal thyroid function, who had undergone PEI 6-18 months before, underwent an MR examination with the same parameters. The signal-to-noise ratio (S/N) of ATN and extranodular gland, as well as ATN volume, were evaluated on the T2-weighted images. On T1-weighted images, ATNs appeared mostly hypointense before treatment, with hyperintense areas during treatment, and were lightly hyperintense 6-18 months after treatment. S/N on T2-weighted images: extranodular gland 3.5-9.2; ATNs, before treatment 13.2-19.7, before the last procedure 7.7-11.6, 1 month after the last procedure 5.6-10.9; previously treated ATNs, 4.3-8.2. No significant volume reduction was observed with MR 1 month after the last procedure. The MR examination time was about 15 minutes. In conclusion, the effect of PEI on ATNs can be evaluated with an MR examination that is not very time consuming.

Purpose: We compared volumetric helical and conventional CT in the study of meniscal injuries., Material and Methods: Thirty-three patients with suspected meniscal tear underwent helical and conventional CT. Common parameters were 512 x 512 matrix, 14-15 cm FOV, 120 kV and 175 mA; helical CT was performed with 2 mm beam thickness, 1.5 mm/s table feed, 1 mm reconstruction index and conventional CT with 2 s scan time, 1 mm slice thickness and 1 mm table feed. All scans were photographed with a Laser printer using the same window (180/100). All patients also underwent sagittal and coronal T2* GE MRI at .5-T; slice thickness was 5 mm and interslice gap 1 mm. Nonparametric scales were used to study the menisci, as follows: for CT we had A = no visible injury; B = diffuse hypodensity (degenerative condition); C = questionable meniscal tear; D = unquestionable meniscal tear. For MRI, we had A = no visible injury; B = grade 1 or 2 injury; C = grade 3 injury; D = grade 4 injury. We used the 1-4 MR grading by Lotysch et al. and by Crues et al. MRI was used as the gold standard. The agreement between helical CT, conventional CT and MRI was calculated with kappa statistics., Results: Helical and conventional CT found 23 and 15 patterns A, 6 and 10 B, 3 and 1 C and 1 and 7 D, respectively. MRI found 15 A, 8 B, 3 C and 7 D. There was no agreement between helical CT and MRI and between helical CT and conventional CT because of the meniscal tears underestimated by the former. Agreement was very high between conventional CT and MRI (p < .001)., Discussion and Conclusions: The main result of our experience is that helical CT appears less sensitive than conventional CT in detecting meniscal tears. The helical CT section profile (more roundish than that of conventional CT) and the lower radiation dose used by helical CT (with increased quantum noise) may have played a key role in its underestimation of meniscal tears.

Introduction: Magnetic resonance (MR) imaging showed high reliability in detecting spine metastases with spin-echo (SE) sequences, T1-weighted sequences being generally more sensitive than T/-weighted ones. We investigated the value of T2*-weighted gradient-echo (GE) sequences in studying spine metastases., Materials and Methods: Twenty patients with established diagnosis of primary carcinoma and clinically suspected thoracic and/or lumbosacral spine metastases underwent .5-T MR imaging and 99mTc-HDP bone scan. The disagreement of GET2*- versus SET2-weighted images as well as versus bone scan and the disagreement of total MR results versus bone scan results were evaluated by McNemar test. The agreement of GET2*- versus SET1-weighted images was evaluated by Cohen's kappa., Results: Of a total of 111 MR signal abnormalities consistent with metastasis, 109 (98.2%) were T2*-hyperintense, whereas only 50 (45.1%) were T2-hyperintense (p < .0001) and 51 (45.9%) were detected with bone scan (p < .0001). Of a total of 121 MR and/or bone scan findings consistent with metastasis, 111 (91.7%) were MR positive, with high disagreement with 61 (50.4%) positive at bone scan (p < .00001). T2*-hyperintensity associated with T1-hypointensity (with or without T2-hyperintensity) was the most frequent pattern (104/111), 93.7%)., Conclusions: T2*-weighted GE sequences seem to be more effective than T2-weighted SE sequences and as effective as T1-weighted SE sequences. MR imaging confirms its ability in detecting abnormalities consistent with spine metastases.

Twenty patients with clinically suspected breast cancer recurrence underwent MRI before and after paramagnetic contrast agent administration (MR mammography, MRM), after negative (4/20), questionable (11/20) or positive (5/20) X-ray mammography (XM). Spin-echo T1-weighted images before and after the i.v. administration of Gd-DTPA (0.15 mmol/kg) were acquired at 1, 3, 5, 7 and 10 minutes. Tissue behavior was studied directly on the images (qualitative analysis) and with dynamic curves of the signal-to-noise ratio and of enhancement rate (quantitative analysis). The histologic examination was performed in all cases--18 of them by surgical excision and in two by needle biopsy only. Seven of seven recurrences exhibited early (at 1 and 3 minutes) and focal qualitative enhancement, exceeding 100% at the quantitative analysis. Twelve of thirteen non-recurrences exhibited no significant qualitative enhancement, less than 40% at the quantitative analysis, while the extant lesion exhibited multifocal delayed (at 5-10 minutes) qualitative enhancement, about 60% at the quantitative analysis, and slight bilateral diffuse enhancement (proliferative dysplasia). MRM had 100% sensitivity, 92.3% specificity, 87.5% positive predictive value and 100% negative predictive value. XM had 100%, 30.8%, 43.7% and 100%, respectively (if we consider as positive all the questionable XM cases). To conclude, MRM is confirmed as a useful imaging technique in suspected breast cancer recurrences, especially after questionable XM exams.

Objective: We compared MRI with two-dimensional echocardiography (2dE) and Doppler echocardiography to determine the diagnostic role of MRI in hypertrophic cardiomyopathy (HCM)., Materials and Methods: Twenty-three patients with 2dE diagnosis of HCM were examined with MRI; 12 of 23 patients were also studied by color (cDE) and continuous wave (cwDE) Doppler echocardiography. Morphologic information and diastolic heart wall thickness were obtained by SE sequences; functional study was performed by gradient echo sequences (cine MR)., Results: The correlation between MR, SE sequences and 2dE was better for septal (r = 0.930, p < 0.01) than for posterolateral (r = 0.739, p < 0.01) wall thickness. The assessment of the distribution of the hypertrophy was changed by MR in five cases. Cine MR functional study showed a systolic subaortic signal void (dynamic obstruction) in 12 of 22 patients and a systolic left atrial signal void (mitral regurgitation) in 17 of 22. Systolic wall thickening was studied by cine MR and 2dE in 11 patients: A good correlation was found for septum (0.01 < p < 0.05) and a poor one for posterolateral wall (p > 0.05). The cine MR and cDE turbulence duration in the left ventricle and atrium showed excellent correlation (p < 0.01). Good agreement was found between the duration of subaortic turbulence (cine MR or cDE) and the pressure gradient (cwDE) (p < 0.01 and 0.01 < p < 0.05, respectively) and between cine MR and cDE semiquantitative estimate of the mitral regurgitation (p < 0.01). In all patients with subaortic MR signal void studied with cwDE, a pressure gradient was present., Conclusion: Magnetic resonance imaging can play an important role in the diagnosis of HCM after 2dE-DE.