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Purpose To evaluate safety and diagnostic accuracy of gadoteridol vs. other macrocyclic gadolinium-based contrast agents (GBCAs) in a large cohort of consecutive and non-selected patients referred for CE-MRI of the CNS. Material and methods Between November 2017 and March 2018, we prospectively enrolled a consecutive cohort of patients referred for neuroradiological CE-MRI (1.5 T MRI). Image quality and adverse events were assessed. Diagnostic performance was determined for a subgroup of patients with truth standard findings available. Comparison was made between patients receiving gadoteridol and patients receiving other macrocyclic GBCAs. Inter-reader agreement (kappa) between two expert neuroradiologists was calculated for the diagnosis of malignancy. Results Overall, 460 patients (220 M/240F; mean age 54 ± 16 years) were enrolled of which 230 received gadoteridol (Group 1) and 230 either gadoteric acid or gadobutrol [n = 83 (36.1%) and n = 147 (63.9%), respectively; Group 2]. Image quality was rated as good or excellent in both groups. The sensitivity, specificity and diagnostic accuracy for determination of malignancy was 88.2%, 96.5% and 95.4%, respectively, for Group 1 and 93.7%, 97.4% and 96.9%, respectively, for Group 2, with no significant differences between groups (P > 0.75) for any determination. Inter-reader agreement for the identification of malignancy was excellent [K = 0.877 (95%CI: 0.758–0.995) and K = 0.818 (95%CI: 0.663–0.972) for groups 1 and 2, respectively; P = 0.0913]. Adverse events occurred in 5 of 460 (1.09%) patients overall, with no significant difference (P = 0.972) between groups. Conclusion Gadoteridol was safe and guaranteed good image quality without significant differences when compared to gadobutrol and gadoteric acid in a wide range of CNS pathologies.

Quantitative evaluation of lesion load in multiple sclerosis (MS) from magnetic resonance imaging (MRI) scans is becoming important in understanding and monitoring the progression of the disease. Methods of MS lesion segmentation based on intensity thresholding offer one of the most robust and easily-implemented means of computing the total lesion volume. This study evaluated the effects of slight changes in the choice of intensity threshold on computed lesion volumes in 20 patients with MS using such a technique. After judging the optimum choice of threshold value, the threshold value was increased and decreased by 3% in 1% steps around this value; we observed a mean change of 15% in computed lesion volumes for 1% changes of threshold value. Larger changes in lesion volume were found when the threshold was changed by larger amounts. On the other hand, the amount of time required for manual review decreased, and the confidence with which manual review could be performed increased when using lower thresholds. This study shows that the choice of threshold is a crucial factor in measuring lesion volumes in MS when using intensity-based techniques. It also suggests that in multicenter and/or longitudinal studies, criteria for choosing the threshold should be developed whereby the threshold level should be set such that all MR visible lesions are above it, in order to minimise the human interaction and, consequently, the reproducibility of the results.

Fast fluid-attenuated inversion recovery (fast-FLAIR) sequences are very sensitive for detecting lesions of patients with multiple sclerosis (MS). Echo planar imaging allows to obtain FLAIR images (EPI-FLAIR) with significantly shorter scanning times. EPI-FLAIR images obtained with 10 measurements are as sensitive as fast-FLAIR for the detection of large MS lesions. Aim of this study was to compare the numbers of MS lesions seen on EPI-FLAIR images with fewer measurements (and, as a consequence, very short scanning times) with those seen on EPI-FLAIR images with 10 measurements. EPI-FLAIR scans with 2 (EPI-2), 4 (EPI-4), 6 (EPI-6), 8 (EPI-8) and 10 (EPI-10) measurements were obtained from 29 MS patients. Lesions seen using each of the five approaches were counted by agreement by two observers. EPI-10 images were used as the "gold standard" for pairwise comparisons. EPI-FLAIR scans with fewer measurements (EPI-2, -4, -6, -8) were all significantly less sensitive than EPI-10 for the detection of small, intermediate and large MS lesions. All the EPI-FLAIR scans, however, fulfilled MR diagnostic criteria for definite MS. When rapid MR scanning of uncooperative MS patients is needed, EPI-FLAIR images covering the entire brain in less than one minute may be considered.

We performed serial monthly magnetization transfer (MT) imaging to evaluate the prevalence and evolution of structural changes in individual enhancing lesions from patients with multiple sclerosis (MS). Every 4 weeks for 3 months, we obtained dual echo, magnetization transfer (MT) imaging and, 5 min after SD (0.1 mmol/kg) gadolinium-DTPA injection, T1-weighted scans from 10 patients with early relapsing-remitting MS. We measured the MT ratio (MTR) of enhancing lesions seen on the entry scans on co-registered quantitative MTR images at entry and during the follow up. Fourty-two enhancing lesions were identified on the entry scans. According to the “maximal random fluctuation” detected for the normal-appearing white matter MTR values, 16 (38%) lesions were classified as “increasing MTR” lesions, 21 (50%) as “stable MTR” lesions, and 5 (12%) as “decreasing MTR” lesions. The classification of the lesions after the first month of follow up strongly predicted the classification at the end of the follow up (chi squared = 20.35, p = 0.0004). These results indicate that the enhancing lesion population in MS is heterogeneous, and that reparative mechanisms occurring after blood-brain barrier opening are not efficient in only a minority of the enhancing lesions from patients with early relapsing-remitting MS.

In this longitudinal study, we evaluated the sensitivities of dual-echo, conventional spin-echo (CSE), and rapid-acquisition relaxation-enhanced (RARE) scans for detecting the appearance of new lesions in multiple sclerosis (MS). Dual echo, CSE, and RARE scans were obtained on four occasions each separated by 28 days from five patients with relapsing-remitting MS using a 1.5-Tesla machine. A total of 44 new lesions were detected by the two sequences. Thirty-five lesions were seen on both sequences, three only on CSE and six only on FSE. This study indicates that CSE may be substituted by RARE when monitoring short-term disease activity in MS.

We compared the volumes of the brain as a whole and of different cerebral structures from patients with multiple sclerosis (MS) and normal subjects. In the patients, we also correlated brain volumes with T2 and T1 lesion loads and disability. A magnetization-prepared rapid acquisition gradient echo (MP RAGE) sequence with subsequent reconstruction of axial 1-mm thick slices and a dual-echo sequence were obtained in 15 patients with relapsing-remitting or secondary progressive MS and 15 sex-, age-, height- and weight-matched normal subjects. The brains and the different cerebral structures studied (cerebral hemispheres, cerebellum and brainstem) were segmented manually by a single observer on the 1-mm MP RAGE scans. The hyperintense lesion volumes seen on dual-echo scans and the hypointense lesion volumes seen on the 1-mm MP RAGE scans were measured using a semi-automated segmentation technique based on local thresholding. Compared to the normal volunteers, patients had significantly lower cerebral ( P =0.008), hemispheric ( P =0.01) and brainstem ( P =0.03) volumes. Cerebral atrophy was detected in seven (47%) MS patients. Patients with brainstem signs had significantly lower mean brainstem volume than the others ( P =0.04). No significant correlations were found between the cerebral volumes and the EDSS scores, the hyperintense lesion volumes and the hypointense lesion volumes. We conclude that cerebral atrophy is a relatively frequent finding in MS, but its relationship with physical disability is modest.

This study was performed to evaluate the correlation between changes of cross-sectional cord area and disability in multiple sclerosis. Axial magnetic resonance images at the C-5 spinal level were obtained at entry and 12 months later for 29 patients with clinically definite multiple sclerosis. The degree of disability was inversely correlated at entry and follow-up with the cross-sectional area and the transverse diameter of the spinal cord. In addition, changes in disability correlated inversely with changes in cross-sectional area (r = -0.4, p = 0.04). These findings suggest that cross-sectional cord area at C-5 might be a useful marker of disease evolution.

PURPOSE To compare the rates of enhancement and changes in lesion burden in patients with multiple sclerosis (MS) and varying levels of disability. METHODS Monthly enhanced MR images of the brain were obtained for 6 months from seven patients with mildly disabling relapsing-remitting MS and from seven patients with secondary progressive MS and severe disability. At entry and 1 year later, two unenhanced T2-weighted images of the brain were also obtained. RESULTS Despite the fact that both groups had clinically active disease and had similar increases in unenhanced MR lesion load, the total number of enhancing lesions was 239 in patients with relapsing-remitting MS (42 on the baseline images, 151 new and 46 persistent during follow-up) (average number of lesions per patient per year was 68) and 21 in those with secondary progressive MS (five on the baseline images, 13 new, and three persistent during follow-up) (average number of lesions per patients per year was seven). CONCLUSION Our data indicate that the rate of enhancement significantly decreases in the more advanced phases of MS. This is important when planning clinical trials, and suggests that mechanisms underlying lesion formation might be dissimilar in different MS patient groups.

This study was performed to achieve a better definition of the nature of the disability in multiple sclerosis (MS). Axial spinal cord magnetic resonance imaging (MRI) at C5 was obtained in 15 patients with benign MS, 17 patients with secondary progressive MS and 10 healthy controls. Patients with secondary progressive MS had smaller spinal cord cross-sectional area (P = 0.01) and transverse diameter (P = 0.006) than patients with benign MS. The degree of disability was inversely correlated with both the cross-sectional area (r = -0.6, P = 0.0018) and transverse diameter (r = -0.5, P = 0.0032) of the cord. Spinal cord atrophy was found in 7 (41%) patients with secondary progressive MS and in 2 (13%) with benign MS. These findings suggest that destructive pathology within MS lesions might play a relevant role in the development of disability in MS.

In this study, we investigated the relationship between multiple sclerosis lesion volumes measured from magnetic resonance imaging scans and image-slice thickness. The lesion volume was computed using a semiautomated thresholding technique from axial scans of the brain of varying slice thickness. Ten patients were studied, and in all cases the computed lesion volume increased with decreasing slice thickness (p = 0.01). Linear extrapolation from our data allowed the lesion volume at very small slice thickness to be estimated; this was found to be on average 20% greater than that obtained using a slice thickness of 5 mm. Furthermore, there were considerable differences in the percentage of change in lesion volume from patient to patient, and it would appear that there is a larger variation with slice thickness for patients with smaller lesions and higher lesion loads.

Transitional progressive multiple sclerosis (MS) is quite an unusual form of presentation and course of the disease. A case with this progressive form is presented and brain MRI and MTI findings are discussed in relation to the possible insight they may provide for understanding the mechanisms that determine progressive disability in MS.

We measured and compared lesion numbers and volumes present on brain magnetic resonance imaging (MRI) scans of patients with multiple sclerosis (MS) acquired with contiguous (scheme A) and interleaved (scheme B) slice acquisition, to evaluate whether there was a gain in sensitivity using the second pattern of acquisition and whether this counterbalanced the doubled acquisition time. Conventional spin-echo (CSE) sequences were performed for eight patient and turbo spin-echo (TSE) sequences for ten. Acquisition scheme B detected 3.8% more lesions than acquisition scheme A (the increase was 3. 1% for CSE and 4.5% for TSE). These differences were not statistically significant. No significant difference in lesion numbers was found when different lesion locations were also considered. Lesion volumes were significantly higher when scheme B was used (P= 0.024). This was due to higher lesion volumes on TSE images (P= 0.006), especially on even-numbered slices (P= 0.008). Inter-slice cross-talk has a negligible effect on lesion numbers and volume estimates in MS for CSE sequence, whilst it cannot be neglected when TSE sequences are used to measure MS lesion volume.