Reproducibility of brain MRI lesion volume measurements in multiple sclerosis using a local thresholding technique: effects of formal operator training.

The assessment of lesion load (LL) on brain magnetic resonance imaging (MRI) scans from patients with multiple sclerosis (MS) is widely used to monitor disease evolution, natural or modified by treatments. In this study, we evaluated the effect of formal operator training on the intra- and inter-observer reproducibility of LL measurements obtained by several operators in a setting similar to that of clinical trials. Proton-density (PD)-weighted, unenhanced and enhanced T1-weighted brain MRI scans were obtained from 10 MS patients.

Central nervous system sarcoidosis--diagnosis and management.

A series of 68 patients with neurosarcoidosis is reported, with particular emphasis on clinical aspects, diagnosis and treatment. A classification system based on clinical diagnostic probability is proposed, consisting of probable and definite disease, the latter being dependent on finding sarcoid granulomas on nervous system histology, which was obtained in 12 patients (18%). The role of investigations, including magnetic resonance imaging (MRI), chest radiography, Kveim skin test, Gallium 67 isotope scanning and cerebrospinal fluid (CSF) studies, is considered.

Correlation between MRI and short-term clinical activity in multiple sclerosis: comparison between standard- and triple-dose Gd-enhanced MRI.

We assessed the relative sensitivities of standard (SD)- and triple-dose (TD) gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) for detecting enhancing lesions in different phases of multiple sclerosis (MS) disease activity. Ten MS patients were studied with monthly brain MRI scans for a 3-month follow-up (i.e.

A longitudinal study comparing the sensitivity of CSE and RARE sequences in detecting new multiple sclerosis lesions.

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 comparison of the sensitivity of monthly unenhanced and enhanced MRI techniques in detecting new multiple sclerosis lesions.

In this longitudinal study, the sensitivities of three magnetic resonance imaging techniques for detecting the appearance of new lesions in multiple sclerosis (MS) were evaluated and compared. Dual-echo conventional spin-echo (CSE), fast fluid-attenuated inversion recovery (fast-FLAIR) and post-contrast T1-weighted scans were obtained on four occasions, each separated by 28 days, from 18 patients with relapsing-remitting MS using a 1.5-T machine.

Primary and transitional progressive MS: a clinical and MRI cross-sectional study.

Background: Ten percent of patients with MS have a progressive course from onset with no history of relapses or remissions. A smaller subgroup follow a similar progressive course but have a single relapse at some point (transitional progressive [TP] MS). To date these patients have been excluded from receiving licensed treatments for MS and from most therapeutic trials.

Sensitivity of enhanced MR in multiple sclerosis: effects of contrast dose and magnetization transfer contrast.

Background And Purposes: New strategies have been developed to improve the sensitivity of contrast-enhanced MR imaging in quantifying disease activity in patients with multiple sclerosis (MS). The goal of the present study was to evaluate the sensitivity of T1-weighted images after injection of a triple dose of contrast material and application of a magnetization transfer (MT) pulse in the detection of enhancing lesions as compared with the conventional approach.

Methods: Monthly MR images were obtained in 13 patients with relapsing-remitting MS for a period of 3 months.

Brain MRI lesion volume measurement reproducibility is not dependent on the disease burden in patients with multiple sclerosis.

We evaluated the potential effect of the lesion burden on the reproducibility of repeated lesion volume (LV) measurements from brain magnetic resonance imaging (MRI) scans of patients with multiple sclerosis (MS). Dual-echo, conventional spin echo brain MRI scans were obtained from 107 patients with MS. On proton density-weighted images, LV was assessed three times by the same raters, using a semi-automated, local thresholding technique for lesion segmentation.

How does brain MRI lesion volume change on serial scans in patients with multiple sclerosis?

Although lesion load changes on conventional T2-weighted brain magnetic resonance imaging (MRI) scans from patients with multiple sclerosis (MS) are used to monitor the effect of treatment, there is no clear definition of how lesion load changes over years according to the lesion load present at a baseline evaluation. In the present study, we evaluated the relationship between lesion load changes over time and lesion load at a baseline evaluation in a group of untreated patients with MS. We scanned nineteen patients on two separate occasions with a mean interval 16.

A multi-centre longitudinal study comparing the sensitivity of monthly MRI after standard and triple dose gadolinium-DTPA for monitoring disease activity in multiple sclerosis. Implications for phase II clinical trials.

In this study we assessed the safety, efficacy and cost-effectiveness of the use of triple dose gadolinium-DTPA (Gd) in serial monthly brain MRI of patients with multiple sclerosis, such as could be selected for clinical trials. The number of enhancing lesions, the number of new enhancing lesions and the number of active scans were used to evaluate the sensitivity of the contrast-enhanced MRI to disease activity. The dose of Gd, and the effect of introducing a delay between the contrast injection and the scan were both appraised.

Detecting new lesion formation in multiple sclerosis: the relative contributions of monthly dual-echo and T1-weighted scans after triple-dose gadolinium.

In this study, we evaluated the frequency of formation of new lesions on brain magnetic resonance imaging (MRI) from patients with relapsing-remitting multiple sclerosis (MS) and defined the relative contributions of unenhanced and enhanced MRI. Every 4 weeks for 3 months, dual-echo and postcontrast T1-weighted (5 min after the injection of 0.3 mmol/kg gadolinium-DTPA) scans were obtained from 28 patients with relapsing-remitting MS.

MRI evolution of new MS lesions enhancing after different doses of gadolinium.

Objective: To investigate the evolution of multiple sclerosis (MS) lesions enhancing after single dose (SD) or triple dose (TD) of gadolinium-DTPA (Gd).

Material And Methods: For 3 months, 30 relapsing-remitting MS patients underwent 2 monthly MRI sessions, consisting of Gd-enhanced T1-weighted scans, after SD (i.e.

A longitudinal brain MRI study comparing the sensitivities of the conventional and a newer approach for detecting active lesions in multiple sclerosis.

Monthly dual-echo spin-echo (SE) and enhanced magnetic resonance imaging (MRI) after the injection of a standard dose (SD) of gadolinium (Gd) is the conventional approach to monitor short-term disease activity in multiple sclerosis (MS). In this study, the sensitivity of this approach in detecting active lesions in MS was compared with that of monthly fast fluid attenuated inversion recovery (FLAIR) scans associated with enhanced MRI after the injection of a triple dose (TD) of Gd. Thirteen patients with relapsing-remitting MS entered the study.

A comparison between the sensitivities of 3-mm and 5-mm thick serial brain MRI for detecting lesion volume changes in patients with multiple sclerosis.

In this longitudinal study the authors evaluated the sensitivity of 3-mm and 5-mm magnetic resonance imaging (MRI) of the brain in the detection of lesion load changes over time in multiple sclerosis (MS). The authors also correlated the changes detected with these two techniques with the changes in disability. Eighteen patients with MS underwent two MRI examinations of the brain--one at entrance into the study and one follow-up examination.

The role of techniques characterised by faster acquisition times in the evaluation of multiple sclerosis.

Magnetic resonance imaging (MRI) methods with shorter acquisition times are considered. Fast spin echo sequences allow faster scanning with images comparable with conventional spin echo. Fast fluid attenuated inversion recovery (fast FLAIR) may provide a more complete picture of multiple sclerosis evolution, but more validation studies are still needed.

Clinical, neurophysiological, and magnetic resonance imaging correlations in multiple sclerosis.

Magnetic resonance imaging (MRI) has a pivotal role in diagnosis of multiple sclerosis and is being increasingly used as a paraclinical measure to assess treatment efficacy in clinical trials. However, the correlations between clinical and MRI findings in patients with multiple sclerosis are weak and, therefore, newer MR techniques are being developed to increase both MRI sensitivity for detecting disease activity and its pathological specificity for better assessing disease evolution. Evoked potentials (EPs) can be used to confirm the diagnosis of multiple sclerosis and their abnormalities are correlated with symptoms and signs referable to involvement of the corresponding nervous pathways.

Relation between MR abnormalities and patterns of cognitive impairment in multiple sclerosis.

Objective: This study correlated the extent of abnormalities detected by different magnetic resonance imaging (MRI) techniques [proton density (PD)-weighted, T1-weighted, and magnetization transfer imaging (MTI)] with the overall cognitive, frontal lobe, and memory impairments in patients with MS.

Patients: There were 30 clinically definite MS patients, with different disease courses.

Exclusion Criteria: psychoactive/steroid treatments, mood disorders, acute relapse phase.

The effect of repositioning on brain MRI lesion load assessment in multiple sclerosis: reliability of subjective quality criteria.

The aim of this study was to assess the variability of lesion load measurements for repeated brain magnetic resonance imaging (MRI) scans judged to have either poor or good repositioning quality on the basis of subjective criteria used for clinical trials in multiple sclerosis (MS). Scan-rescan variability was also compared with the intra-observer variability assessed from three repeated volume measurements of the same scan. Nine patients with MS were studied; each of them underwent the scan-rescan procedure on the same day.

Magnetization transfer ratios in multiple sclerosis lesions enhancing after different doses of gadolinium.

We performed serial monthly magnetization transfer (MT) imaging to evaluate whether MS lesions that enhance only after the injection of a triple dose (TD) of gadolinium-DTPA (Gd) have different pathologic characteristics and evolution than those that enhance after the injection of a standard dose (SD). Every 4 weeks for 3 months and in two separate sessions, we obtained T1-weighted scans from 10 patients with relapsing-remitting MS, 5 minutes after SD (0.1 mmol/kg) or TD (0.

Intraobserver and interobserver variability in measuring changes in lesion volume on serial brain MR images in multiple sclerosis.

Purpose: We evaluated the intraobserver and interobserver variability in measuring long-term changes in the volume of brain lesions on 5- and 3-mm-thick MR sections in patients with multiple sclerosis.

Methods: Eighteen 18 patients were scanned on two separate occasions with a mean interval of 16.4 months between the two examinations.

A preliminary study comparing the sensitivity of serial monthly enhanced MRI after standard and triple dose gadolinium-DTPA for monitoring disease activity in primary progressive multiple sclerosis.

We performed this study to evaluate and compare the numbers of total and new enhancing lesions detected on serial monthly brain magnetic resonance imaging (MRI) after the injection of a standard dose (SD) and a triple dose (TD) of gadolinium-DTPA (Gd) in patients with primary progressive multiple sclerosis (PPMS). Every 4 weeks for 3 months and in two separate sessions, MRI scans were obtained from 5 patients with PPMS, 5 (early) and 20 minutes (delayed) after SD (0.1 mmol/kg) or TD (0.

Intraobserver and interobserver variability in schemes for estimating volume of brain lesions on MR images in multiple sclerosis.

Purpose: Our goal was to evaluate the intraobserver and interobserver reproducibility of measurements of brain lesion load in multiple sclerosis (MS) by using two proposed acquisition schemes.

Methods: Three-millimeter-thick conventional spin-echo (CSE) and fast fluid-attenuated inversion-recovery (FLAIR) sequences were obtained and the lesions segmented using a semiautomated technique based on local thresholding to calculate intraobserver and interobserver reproducibility. These were compared with images obtained from two separate MR units in which 5-mm CSE sequences were obtained and segmented by using the local thresholding technique and also by manual outlining.

Increased spatial resolution using a three-dimensional T1-weighted gradient-echo MR sequence results in greater hypointense lesion volumes in multiple sclerosis.

Purpose: Our goal was to evaluate whether improved spatial resolution of MR images results in the detection of higher volumes of hypointense lesions in patients with multiple sclerosis (MS).

Methods: A magnetization-prepared rapid acquisition gradient-echo (MP-RAGE) sequence with subsequent reconstruction of axial sections with 5-, 3-, and 1-mm thickness and a dual-echo sequence were obtained in 16 patients with relapsing-remitting or secondary-progressive MS. The volumes of MR imaging abnormalities present on each of these studies were measured using a semiautomated segmentation technique based on local thresholding.

The influence of slice orientation on brain MRI lesion load measurement in multiple sclerosis.

This study aimed at evaluating the influence of a different slice orientation on brain magnetic resonance imaging (MRI) lesion load in multiple sclerosis (MS). Fifteen MS patients were scanned obtaining both axial and sagittal conventional spin echo (24 slices; TR 2400, TE 30/80) brain MRI. The total lesion load (TLL) was assessed twice for each scan, using a semi-automated local thresholding technique and the same marked hardcopies.

Improving interobserver variation in reporting gadolinium-enhanced MRI lesions in multiple sclerosis.

Gadolinium-enhanced MRI is a sensitive and objective means to monitor disease activity in multiple sclerosis (MS). We evaluated the interobserver agreement and the value of observer training in reporting enhancing lesions from serial MRI. Scans of 16 MS patients were evaluated by five inexperienced and five experienced observers before and after consensus formation and training.