Use of herbal remedies by multiple sclerosis patients: a nation-wide survey in Italy.

Though recent progress in multiple sclerosis (MS) treatment is remarkable, numerous unmet needs remain to be addressed often inducing patients to look for complementary and alternative medicines (CAM), especially herbal remedies (HR). HR use, scarcely investigated in MS, may cause adverse reactions (AR) and interfere with conventional treatment. We performed a survey aimed at evaluating use and attitudes towards HR and factor associated to HR use. Other CAM use and attitudes have been investigated as well. Multiple-choice questionnaires were distributed to MS out patients attending 14 Italian referral Centers. Multivariable logistic regression was used to identify HR use determinants. Present/past HR use for either MS or other diseases was reported in 35.6 % of 2419 cases (95 % CI 36.0-40.0 %). CAM use was reported in 42.5 % of cases. Independent predictors of HR use were represented by higher education, geographic area, dissatisfaction with conventional treatment of diseases other than MS and benefit perception from CAM use. Both HR and CAM use were not always disclosed to the healthcare professional. In conclusion, HR and other CAM appear to be popular among MS patients. The involvement of the healthcare professionals appears to be scarce with potential risk of AR or interference with conventional treatments.

Newly produced T and B lymphocytes and T-cell receptor repertoire diversity are reduced in peripheral blood of fingolimod-treated multiple sclerosis patients.

BACKGROUND: Fingolimod inhibits lymphocyte egress from lymphoid tissues, thus altering the composition of the peripheral lymphocyte pool of multiple sclerosis patients. OBJECTIVE: The objective of this paper is to evaluate whether fingolimod determines a decrease of newly produced T- and B-lymphocytes in the blood and a reduction in the T-cell receptor repertoire diversity that may affect immune surveillance. METHODS: Blood samples were obtained from multiple sclerosis patients before fingolimod therapy initiation and then after six and 12 months. Newly produced T and B lymphocytes were measured by quantifying T-cell receptor excision circles and K-deleting recombination excision circles by real-time PCR, while recent thymic emigrants, naive CD8(+) lymphocytes, immature and naive B cells were determined by immune phenotyping. T-cell receptor repertoire was analyzed by complementarity determining region 3 spectratyping. RESULTS: Newly produced T and B lymphocytes were significantly reduced in peripheral blood of fingolimod-treated patients. The decrease was particularly evident in the T-cell compartment. T-cell repertoire restrictions, already present before therapy, significantly increased after 12 months of treatment. CONCLUSIONS: These results do not have direct clinical implications but they may be useful for further understanding the mode of action of this immunotherapy for multiple sclerosis patients.

Modulation of the central memory and Tr1-like regulatory T cells in multiple sclerosis patients responsive to interferon-beta therapy.

BACKGROUND: Interferon-beta is used to reduce disease activity in multiple sclerosis, but its action is incompletely understood, individual treatment response varies among patients, and biological markers predicting clinical benefits have yet to be identified. Since it is known that multiple sclerosis patients have a deficit of the regulatory T-cell subsets, we investigated whether interferon-beta therapy induced modifications of the two main categories of regulatory T cells (Tregs), natural and IL-10-secreting inducible Tr1 subset, in patients who are biologically responsive to the therapy. METHODS: T-cell phenotype was determined by flow cytometry, while real-time PCR was used to evaluate interferon-beta bioactivity through MxA determination, and to measure the RNA for IL-10 and CD46 molecule in peripheral blood mononuclear cells stimulated with anti-CD46 and anti-CD3 monoclonal antibodies, which are known to expand a Tr1-like population. RESULTS: Interferon-beta induced a redistribution of natural Treg subsets with a shift of naive Tregs towards the 'central memory-like' Treg population that expresses the CCR7 molecule required for the in vivo suppressive activity. Furthermore, in a subgroup of treated patients, the CD46/CD3 co-stimulation, probably through the Tr1-like subset modulation, increased the production of RNA for IL-10 and CD46. The same group showed a lower median EDSS score after two years of therapy. CONCLUSIONS: The selective increase of 'central memory-like' subset and the involvement of the Tr1-like population may be two of the mechanisms by which interferon-beta achieves its beneficial effects. The quantification of RNA for IL-10 and CD46 could be used to identify patients with a different response to interferon-beta therapy.

The effect of natalizumab on cognitive function in patients with relapsing-remitting multiple sclerosis: preliminary results of a 1-year follow-up study.

The objective of the study was to assess the natalizumab effect on the course of cognitive impairment in patients with relapsing-remitting multiple sclerosis (MS). Patients with active relapsing-remitting MS (n = 17) were treated with natalizumab for 1 year. The quasi control group included patients (n = 7) with clinically stable MS. Assessment of disease course [expanded disability status scale (EDSS); number of relapses] and neuropsychological impairment [Wisconsin card sorting test (WCST); controlled oral word associations; verbal/non-verbal memory tests; paced auditory serial addition test] was conducted at baseline and after 1 year. Natalizumab-treated patients experienced significantly fewer relapses compared with the previous year (P < 0.05). At 1-year follow-up, EDSS score was unchanged and neuropsychological assessments of memory/executive functions showed a significant improvement in natalizumab-treated patients (all P < 0.05). No changes were observed in the quasi control group. This preliminary study suggests that natalizumab could be effective in ameliorating cognitive functions in patients with active relapsing-remitting MS, over 1-year follow-up.

Natalizumab efficacy on cognitive impairment in MS.

We report follow-up data on the efficacy of natalizumab therapy on neuropsychological impairment on an italian MS group of 39 patients at 1 year and of 11 patients at 2 years. Results show a significant reduction in relapse rate, in the number of impaired neuropsychological tests as well as in several single executive function and reasoning tests scores at 1 year. Improvement persisted at 2 years, including also memory and speed processing tasks. These data support the efficacy of natalizumab therapy in all the clinical domains, including cognitive deterioration, in multiple sclerosis patients.

Natalizumab therapy of multiple sclerosis: recommendations of the Multiple Sclerosis Study Group--Italian Neurological Society.

Three years after the introduction of natalizumab (NA) therapy for the second line treatment of relapsing-remitting multiple sclerosis (MS), Italian MS centers critically reviewed the scientific literature and their own clinical experience. Natalizumab was shown to be highly efficacious in the treatment of MS. However, the risk of progressive multifocal leukoencephalopathy was confirmed and defined better. This article summarizes the MS-SIN Study Group recommendations on the use of NA in MS, with particular reference to the appropriate selection and monitoring of patients as well as to the management of adverse events.

[Clinical usefulness of the reticulocyte hemoglobin equivalent in chronic hemodialysis patients]. / Utilidad clínica de la hemoglobina reticulocitaria equivalente en pacientes en hemodialisis crónica.

BACKGROUND: Iron deficiency is the main cause of failure to respond to erythropoietin (EPO) in haemodialysis patients. Several laboratory tests to detect the deficiency, ferritin and transferrin saturation (TSat) are the most commonly used but its limitations in this patient population are necessary to find other parameters to improve the identification of iron-deficient state. OBJECTIVE: To evaluate the ability of Reticulocyte Hemoglobin Equivalent (RET-He) to predict iron deficiency, taking as a reference standard to the increase of hemoglobin in response to iron intake. MATERIALS AND METHODS: 44 patients on chronic hemodialysis and fixed-dose EPO received 400 mg of intravenous iron. Were measured Hb, Ret-He, IRF, and ferritin prior to iron administration. After 20 to 30 days of completion of loading the patients were classified as responders if hemoglobin increased by at least 0.8 g / L and non-responders if this increase did not occur. RESULT: 25 patients were responders, the ROC curves analysis showed the Ret-He with the largest AUC of 0.862 similar to the AUC of 0.833 that showed the IST, but the first is more sensitive (72% CI 95%: 51-88% vs 52% 95% CI 31-72%) and similar specificity (94.7% CI 95%: 74-100% vs 100% 95% CI 82-100%). Ferritin AUC was 0.772 and finally the IRF AUC was 0.7. The Ret-He, to a cutoff of 29.5 pg was the best combination of sensitivity and specificity (72 and 94.7 respectively), and the sensitivity of the combination Ret-He/IST rose to 80% specificity 94.7%. CONCLUSIONS: According to these results it could consider to Ret-He and the Ret-He/IST combination of clinical utility for the identification of the iron deficit in patients in chronic haemodialysis.

Progranulin gene variability increases the risk for primary progressive multiple sclerosis in males.

Progranulin (GRN) gene variability has been analyzed in a sample of 354 patients with multiple sclerosis (MS) compared with 343 controls. No significant differences were observed, but by stratifying according to MS subtypes, a significant increased frequency of the rs2879096 TT genotype was found in primary progressive MS (PPMS) patients versus controls (16.0 vs 3.5%, P=0.023, odds ratio (OR) 5.2, 95% confidence interval (CI) 1.2-21.4). In addition, in PPMS, an association with the C allele of rs4792938 was observed (55.3 vs 33.5%, P=0.011, OR 2.4, 95% CI 1.2-4.7). An independent population was studied as replication, failing to confirm results previously obtained. Stratifying according to gender, an association with rs4792938 C allele was found in male PPMS patients compared with controls (40.7 vs 26.9%, P=0.002, OR 1.87, 95% CI 1.2-2.8). An association with the rs2879096T allele was observed (29.2 in patients compared with 18.9% in controls, P=0.012, OR 1.77, 95% CI 1.1-2.8). Haplotype analysis showed that TC haplotype frequency is increased in PPMS male patients compared with male controls (25.7 vs 16.6%; P=0.02, OR 1.69, 95% CI 1.1-2.7), whereas the respective GC haplotype seems to exert a protective effect, as its frequency is decreased in patients compared with controls (55.8% vs 70.9%; P=0.001, OR 0.52, 95% CI 0.4-0.8). Therefore, GRN haplotypes likely influence the risk of developing PPMS in males.

A diffusion tensor MRI study of cervical cord damage in benign and secondary progressive multiple sclerosis patients.

BACKGROUND: Diffusion tensor (DT) MRI enables quantification of the severity of brain and cervical cord pathology in multiple sclerosis (MS). OBJECTIVE: To investigate DT MRI patterns of cervical cord damage in patients with benign MS (BMS) and secondary progressive MS (SPMS), in order to achieve a better understanding of the mechanisms underlying the development of irreversible disability in MS. METHODS: Conventional and DT MRI scans of the cervical cord and brain were acquired from 40 BMS patients, 28 SPMS patients and 18 healthy individuals. Cervical cord and brain mean diffusivity (MD) and fractional anisotropy (FA) maps were created and average MD and FA were calculated. Cross sectional cord area (CSA) was also computed. RESULTS: 37 (92%) BMS patients and all (100%) SPMS patients had macroscopic cervical cord lesions. Compared with healthy individuals, BMS patients had higher average cord MD while SPMS patients had higher average cord MD, lower average cord FA and lower average CSA. Compared with BMS patients, SPMS patients had lower cord average FA and lower average CSA. In MS patients, Expanded Disability Status Scale (EDSS) was correlated with CSA (r = -0.47, p<0.0001), average cord FA (r = -0.37, p = 0.002) and brain T2 lesion volume (LV) (r = 0.34, p = 0.005). A multivariate regression model identified CSA, average cord FA and brain T2 LV as variables independently influencing the EDSS score (r = 0.58, p<0.0001). CONCLUSIONS: Cervical cord damage outside focal macroscopic lesions is limited in patients with BMS. The assessment of cord and brain pathology provides complementary information to improve the understanding of disability accumulation in MS.

Renewal of the T-cell compartment in multiple sclerosis patients treated with glatiramer acetate.

The immunomodulating activity of glatiramer acetate on T-cells of multiple sclerosis patients has only been partially clarified. The objective of this work was to investigate whether glatiramer acetate modifies thymic release of newly produced T-cells and the peripheral composition of the T-cell repertoire. T-cell receptor excision circles, (thymic) naive (CD4(+)CD45RA(+)CCR7(+)CD31(+)) T helper cells, and central (CD4(+)CD45RA(-)CCR7(+)) and effector (CD4(+)CD45RA(-)CCR7(-)) memory T-cells were evaluated in 89 untreated patients, 84 patients treated for at least 1 year, and 31 patients beginning treatment at the time of inclusion in the study and then followed-up for 12 months; controls were 81 healthy donors. The T-cell repertoire was analysed in selected samples. The percentage of (thymic)naive T helper cells was diminished in untreated patients, but rose to control values in treated subjects; a decrease in central memory T-cells was also observed in treated patients. Follow-up patients could be divided into two subgroups, one showing unmodified (thymic)naive T helper cells and T-cell diversity, the other in which the increased release of new T-cells was accompanied by modifications of the T-cell repertoire. Glatiramer acetate modifies the peripheral T-cell pool by activating a thymopoietic pathway of T-cell release that leads to a different setting of T-cell diversity and, likely, to a dilution of autoreactive T-cells.

Lack of replication of KIF1B gene in an Italian primary progressive multiple sclerosis cohort.

BACKGROUND: KIF1B gene represents the first non-inflammatory gene with a putative role on axonal loss and neurodegeneration found to be associated with multiple sclerosis (MS). The objective of this study is to test the association of the rs10492972 C allelic variant of KIF1B gene in a large Italian cohort of patients with primary progressive and progressive relapsing MS (PPMS and PRMS), which represents a subtype of MS mainly driven by neurodegenerative phenomena. METHODS: rs10492972 has been genotyped in an outbred sample of 222 primary PPMS and PRMS and 221 healthy controls of unique northern Italian origin using the TaqMan assay. RESULTS: A non-significant age- and sex-adjusted odds ratio of 0.96 [95% confidence interval (CI) 0.71-1.31] has been found in C carriers, and a non-significant risk of 0.99 [95% CI 0.77-1.63] in C carriers according to a dominant model. Stratification by sex, age at onset younger than 35 years and symptoms at the onset of the disease did not reveal any significant findings. No influence on disability progression, measured with the multiple sclerosis severity score, was found in C carriers. CONCLUSIONS: These results suggest that there is no effect in carrying the rs10492972 C variant on the risk of disease as well as on the rate of disability progression in a cohort of Italian patients with PPMS and patients with PRMS. These data need to be confirmed in an independent sample of patients with progressive MS.

Comparison of GEANT4 very low energy cross section models with experimental data in water.

PURPOSE: The GEANT4 general-purpose Monte Carlo simulation toolkit is able to simulate physical interaction processes of electrons, hydrogen and helium atoms with charge states (H0, H+) and (He0, He+, He2+), respectively, in liquid water, the main component of biological systems, down to the electron volt regime and the submicrometer scale, providing GEANT4 users with the so-called "GEANT4-DNA" physics models suitable for microdosimetry simulation applications. The corresponding software has been recently re-engineered in order to provide GEANT4 users with a coherent and unique approach to the simulation of electromagnetic interactions within the GEANT4 toolkit framework (since GEANT4 version 9.3 beta). This work presents a quantitative comparison of these physics models with a collection of experimental data in water collected from the literature. METHODS: An evaluation of the closeness between the total and differential cross section models available in the GEANT4 toolkit for microdosimetry and experimental reference data is performed using a dedicated statistical toolkit that includes the Kolmogorov-Smirnov statistical test. The authors used experimental data acquired in water vapor as direct measurements in the liquid phase are not yet available in the literature. Comparisons with several recommendations are also presented. RESULTS: The authors have assessed the compatibility of experimental data with GEANT4 microdosimetry models by means of quantitative methods. The results show that microdosimetric measurements in liquid water are necessary to assess quantitatively the validity of the software implementation for the liquid water phase. Nevertheless, a comparison with existing experimental data in water vapor provides a qualitative appreciation of the plausibility of the simulation models. The existing reference data themselves should undergo a critical interpretation and selection, as some of the series exhibit significant deviations from each other. CONCLUSIONS: The GEANT4-DNA physics models available in the GEANT4 toolkit have been compared in this article to available experimental data in the water vapor phase as well as to several published recommendations on the mass stopping power. These models represent a first step in the extension of the GEANT4 Monte Carlo toolkit to the simulation of biological effects of ionizing radiation.

Neuropsychological rehabilitation in adult multiple sclerosis.

Neuropsychological impairment affects 40-65% of multiple sclerosis patients, mainly involving speed in information processing, attention, executive functions and memory. Deterioration occurs over time independently from disability and seems to correlate particularly with magnetic resonance imaging (MRI) atrophy measures. Studies on therapies effective in controlling cognitive impairment are scanty. We found that intensive and specific training of attention, information processing and executive functions is significantly effective in ameliorating both neuropsychological treated functions and in reducing depression. Preliminary functional MRI data suggest that possible neural correlates of this neuropsychological training could be an exercise-induced activation of prefrontal and cingulate cortices.

Longitudinal serum neurofilament light chain (sNfL) concentration relates to cognitive function in multiple sclerosis patients.

BACKGROUND: Serum neurofilament light chain (sNfL) may be used as a biological marker of disease progression in multiple sclerosis (MS), although longitudinal studies correlating cognitive deficits to sNfL are limited. OBJECTIVE: To longitudinally investigate the relation between cognitive dysfunction, sNfL and MRI brain volume in a relapsing remitting MS patients. METHODS: 18 MS patients (9 males and 9 females, mean age 45 years, mean education 12.6 years) all prescribed with interferon beta 1a (44 mcg 3 times per week), are longitudinally evaluated by means of annual clinical exam with EDSS, neuropsychological evaluation with Brief repeatable battery (BRB) and Delis Kaplan Executive function test (DKEFS), dosage of sNfL (SIMOA) and MRI. RESULTS: Here are reported the results of 1 year follow-up. A significantly higher sNfL in MS compared to healthy controls and higher sNfL in patients with greater cognitive impairment were found. Cognitive Impairment Index, memory, executive function tests correlated with sNfL. Gray matter volume resulted unchanged at 1-year follow-up; a weak correlation between some tests' score and selective cortical brain areas was found. CONCLUSION: Our longitudinal pilot study confirms that sNfL are related to cognitive abilities, confirming data of other authors from retrospective studies.

MR imaging assessment of brain and cervical cord damage in patients with neuroborreliosis.

BACKGROUND AND PURPOSE: Neuroborreliosis is frequently indistinguishable from multiple sclerosis (MS) on both clinical and radiologic grounds. By using MR imaging, we assessed "occult" brain white matter (WM), brain gray matter (GM), and cervical cord damage in patients with neuroborreliosis in an attempt to achieve a more accurate picture of tissue damage in these patients, which might contribute to the diagnostic work-up. METHODS: We studied 20 patients with neuroborreliosis and 11 sex- and age-matched control subjects. In all subjects, we acquired dual echo, T1-weighted, diffusion tensor (DT) and magnetization transfer (MT) MR imaging scans of the brain and fast short-tau inversion recovery and MT MR imaging scans of the cervical cord. T2-visible lesion load was measured by using a local thresholding segmentation technique. Mean diffusivity and fractional anisotropy histograms of the brain and cervical cord MT ratio histograms were produced. Normalized brain volumes (NBV) were measured by using SIENAx. RESULTS: Brain T2-visible lesions were detected in 12 patients, whereas no occult damage in the normal-appearing WM and GM was disclosed by using MT and DT MR imaging. No macroscopic lesions were found in the cervical cord, which was also spared by occult pathology. NBV did not differ between patients with neuroborreliosis and control subjects. CONCLUSION: This study shows that, contrary to what happens in MS, occult brain tissue damage and cervical cord pathology are not frequent findings in patients with neuroborreliosis. These observations might be useful in the diagnostic work-up of patients with neuroborreliosis and T2 brain lesions undistinguishable from those of MS.

Mitoxantrone for multiple sclerosis.

BACKGROUND: Mitoxantrone (MX) has been shown to be moderately effective in reducing the clinical outcome measures of disease activity in multiple sclerosis (MS) patients. OBJECTIVES: The objective was to assess the efficacy and safety of MX in relapsing-remitting MS (RRMS), progressive relapsing MS (PRMS) and secondary progressive MS (SPMS). SEARCH STRATEGY: We searched the Cochrane MS Group Trials Register (searched April 2005), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2004), MEDLINE (Pub Med) (January 1966 to April 2005), EMBASE (January 1974 to April 2005), and reference lists of articles. We also undertook hand searching and contacting trialists and pharmaceutical companies. SELECTION CRITERIA: The trials were selected if double-blinded, placebo-controlled, randomised, irrespective of eventual additive therapy (such as steroids). DATA COLLECTION AND ANALYSIS: Three reviewers independently selected articles for inclusion, assessed trials' quality and extracted data. MAIN RESULTS: Four trials involving 270 participants were included. MX was found to reduce the progression of disability at 2 years follow-up (proportion of participants with 6-months confirmed progression of disability: Odds Ratios (OR) 0.3, p = 0.05). Similar figures were found regarding the reduction in annualised relapse rate and the proportion of patients free from relapses at 1 and 2 years, as well as the number of patients with active MRI lesions at 6 months/ 1 year only. Side effects reported in the trials were more frequent in treated patients than in controls. Caution must be exercised in drawing conclusions from such data because of the heterogeneous quality and characteristics of the included trials, which are different in terms of treatment schedule and type of enrolled patients. More than half of the included patients came from a single study. Moreover, from the included trials, it was not possible to estimate the long-term efficacy and safety of MX, which may raise concerns about the risk of cardiotoxicity and therapy-related leukemias, which is increasingly reported in the literature. AUTHORS' CONCLUSIONS: MX is moderately effective in reducing the disease progression and the frequency of relapses in patients affected by RR, PR and SP MS in the short-term follow-up (2 years), even if the results are based on trials heterogeneous in terms of drug dosage and inclusion criteria. No major neoplastic or symptomatic cardiotoxicity related to MX have been reported from the trials. However, longer follow-up studies are highly warranted to better explore the efficacy and safety of the drug, mainly as regards the long-term risk of therapy-related leukemias and cardiotoxicity. As a conclusion, MX has a partial efficacy, but, due to its unclear long-term safety profile, it should be used to treat patients with worsening RR and SP MS with evidence of worsening disability.

Early peripheral nerve abnormalities in impaired glucose tolerance.

Increased prevalence of impaired glucose tolerance (IGT) has been recently detected in patients with painful sensory neuropathy. To determine whether nerve abnormalities are present in IGT we investigated IGT subjects without clinical neuropathy. Nerve conduction studies (NCS) were performed in 12 subjects with IGT without symptoms and signs of neuropathy. The results were compared with those obtained from 12 patients with type 2 diabetes (DM) without clinical neuropathy and 12 healthy controls. Sensory NCS of the sural nerve were performed on different segments, the distal-leg (10 cm proximal to the lateral malleolus) and the proximal-leg segment (10 cm more proximal). The distal conduction velocity of the sural nerve was increased in IGT subjects, compared both to healthy controls and DM patients. No difference was found among the groups with respect to the sensory conduction velocity of the sural nerve fibers in the proximal-leg segment. A reduction of both distal and proximal amplitudes of the sural nerve action potentials was detected in DM patients compared with IGT subjects and controls. The abnormal conduction velocity in the distal segment of the sural nerve, observed in IGT subjects without clinical neuropathy, suggests that the myelin dysfunction of the distal sensory fibers represents the earliest detectable nerve response to the hyperglycemia. The reduced amplitude of the sural nerve action potential in asymptomatic patients with DM arises from the axonal degeneration and represents a more advanced stage of nerve disease.

Gadolinium-pentetic acid magnetic resonance imaging in patients with relapsing remitting multiple sclerosis.

Ten patients with relapsing-remitting multiple sclerosis have been studied by serial gadolinium-pentetic acid magnetic resonance imaging (MRI) every 14 days for 3 months. At the end of the follow-up, seven relapses occurred in six patients; no therapy was administered during the study. Ninety-three enhancing lesions were collected in eight patients. With regard to the duration of the enhancement, 32 lesions were detected in only one MRI scan and 32 were found in more MRI scans (most of the lesions occurring in two serial examinations). Four old lesions increased their size with delayed enhancement. Correlation was found between the relapses and the gadolinium-pentetic acid-enhancing areas only for one brain-stem and two cervical spinal cord lesions. Gadolinium-pentetic acid MRI provides useful information about activity of the disease that cannot be obtained clinically even if the dynamic of the lesions may be undervalued in old plaques.

The effect of imprecise repositioning on lesion volume measurements in patients with multiple sclerosis.

In this study, we evaluated the effect of imprecision in patient repositioning encountered in real life on multiple sclerosis (MS) lesion volumes measured from MRIs. We also evaluated two putative methods for reducing the variability in these lesion volume measurements: first, a reduction of slice thickness (from the conventional 5 mm to 3 mm) and second, the application of a new repositioning technique based on the use of head immobilization shells. We evaluated the errors in lesion volume by scanning 10 patients a total of four times using the two slice thicknesses and two repositioning methods (conventional and using a head immobilization shell). The mean absolute percentage difference between two corresponding scans was 6.8% (range, 1.24 to 11%) using conventional slice thickness and repositioning, 4.1% (range, 0.7 to 5.56%) using conventional slice thickness and head immobilization shells, 2.6% (range, 0.8 to 6.66%) using the conventional repositioning technique and 3-mm slice thickness, and 1.4% (range, 0.2 to 6.14%) using slice thickness of 3 mm and head immobilization shells. These mean absolute differences were significantly different (p = 0.0008). Our results indicate that the effect of repositioning errors of the order of those that can be encountered in the daily life situation of clinical trials affects significantly lesion load measurements in MS and that the combined use of thinner slices and more accurate repositioning techniques can markedly improve the reproducibility of such measurements.