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S T Frequin

Publications and source records attributed to S T Frequin.

17 recordsLinked to original sources
PubMed1998

Patterns of brain magnetic resonance abnormalities on T2-weighted spin echo images in clinical subgroups of multiple sclerosis: a large cross-sectional study.

To substantiate differences in magnetic resonance (MR) patterns in clinical subgroups of multiple sclerosis (MS), we analyzed T2-weighted MR images of a large regional population of MS patients (n = 188). The patients had already been classified according to recent consensus definitions regarding the clinical course of MS into relapsing-remitting (RR), secondary progressive (SP) or primary progressive (PP). Significant (p < 0.01; Spearman test) differences were present between RR and SP patients regarding total lesion load, size and location of lesions. RR and PP patients showed similar MR patterns. PP and SP patients differed in total lesion load, small and medium-sized lesions. The degree of atrophy was highest for SP patients. The clinical progression rate [Expanded Disability Status Scale (EDSS)/disease duration] was similar for various subgroups; the MR progression rate (total lesion score/disease duration) was significantly larger for SP than for PP patients. The lesions load disability quotient (total lesion load/EDSS) differed between RR and PP patients and also between SP and PP patients. In SP patients, the total lesion load correlated significantly (Spearman rank correlation coefficient of 0.52) with EDSS. We conclude that PP patients differ in MR abnormalities from SP patients, that PP and RR patients have similar MR abnormalities and that RR and SP patients are at a different end of the same spectrum of the disease. As the dynamics and clinical impact of MS lesions are different in the various clinical subgroups, they should be considered separately in clinical trials.

Adult↗
PubMed1997

Specific power calculations for magnetic resonance imaging (MRI) in monitoring active relapsing-remitting multiple sclerosis (MS): implications for phase II therapeutic trials.

Inhomogeneous patient samples have been used in previous studies to determine the power of magnetic resonance imaging (MRI) for trial monitoring in multiple sclerosis (MS). These power-calculations might not be applicable to the active relapsing-remitting patient who is preferably included in trials. In order to reevaluate the power-calculations for MRI in the monitoring of treatment in strictly relapsing-remitting MS and to compare the power of different trial designs we studied 12 relapsing-remitting MS patients prospectively for a median period of 12 months using monthly clinical assessments and gadolinium-enhanced MRI. A median number of two clinical relapses/patient occurred of which a median of one was treated with steroids. A median of 1.59 new lesions/scan/patient was detected (range 0-8). The total number of new active lesions correlated significantly with study period relapses (SRCC = 0.72, P = 0.023). Computer simulations using the bootstrap technique yielded mostly lower power values for a parallel groups design than in previous studies except for short follow-periods in larger samples. In this-sample the open cross-over design was found to be between 20 and 40% more powerful. Results of power-calculations are clearly sample dependent implying that for treatment trial monitoring using MRI in relapsing-remitting MS conservative sample size estimates are to be used. In an active patient group open cross-over trial designs could be a very powerful alternative to parallel groups design.

Adult↗
PubMed1996

Methylprednisolone treatment in multiple sclerosis: effect of treatment, pharmacokinetics, future.

High dose intravenous methylprednisolone treatment is effective and safe in the treatment of relapses in multiple sclerosis, but the long term effects are unclear. Pharmacokinetics are almost unknown, but may be very important for the understanding of the clinical and paraclinical effects. In view of what is known now, IVMP should have a prominent place in basic and clinical MS research.

Dose-Response Relationship, Drug↗
PubMed1996

Magnetic resonance imaging of epilepsy in multiple sclerosis: a case control study. Implications for treatment trials with 4-aminopyridine.

A case-control study of epilepsy in multiple sclerosis (MS) is presented using magnetic resonance (MR) imaging to semiquantitatively assess cortical-subcortical lesion load. In this sample of 13 pairs of cases with MS and epilepsy and controls with MS without epilepsy we found statistically higher cumulated cortical-subcortical lesion loads in the cases than in the controls (Wilcoxon, P = 0.036). Total lesion loads (cortical-subcortical plus deep white matter loads) did not differ significantly (P > 0.1) between cases and controls. The relative risk for seizures as determined by the odds ratio of a cortical-subcortical lesion load of > or = 20 was 8.8 (chi 2 = 5.23, P 0.025), the odds ratio of a large (> 1 cm) cortico-subcortical lesion was 4.7 (chi 2 = 4.9, P < 0.05), while the 2 MR criteria combined show an odds ratio of 19.2 (chi 2 = 8.0, P < 0.005). We conclude that: first, the presence of cortical-subcortical lesions in part accounts for the occurrence of seizures in MS patients; second, due to the substantial overlap of MR imaging scores between cases and controls the ultimate use of these MR imaging findings in the management of individual patients or in the organizations of trials should depend on the expected benefit of the treatment. If the benefit is only moderate or not known a cautious approach with exclusion of cases showing a substantial cortical-subcortical lesion load on MR imaging seems appropriate in trials with drugs, like 4-aminopyridine, that lower the epileptic threshold.

4-Aminopyridine↗
PubMed1995

Correlating MRI and clinical disease activity in multiple sclerosis: relevance of hypointense lesions on short-TR/short-TE (T1-weighted) spin-echo images.

Magnetic resonance imaging (MRI) is being used as an outcome criterion in therapeutic trials in multiple sclerosis (MS) on the assumption that it, as a sensitive marker of biologic disease activity, could serve as a surrogate marker of disability. We evaluated the relation between MRI findings and disability in a quantitative follow-up study of 48 MS patients. Median duration of follow-up was 24 months (range, 10 to 42 months). Computer-assisted volume measurements employing a seed-growing technique yielded a standard error of measurement of 0.275 cm2. The median total area of the hyperintense lesions on the initial T2-weighted images was 8.4 cm2. The median increase was 0.76 cm2/yr (9%). In a subgroup (n = 19) with short-TR/short-TE spin-echo (SE) images, we measured the hypointense lesion load. The median total area of the lesions at entry was 0.70 cm2, with a median increase of 0.28 cm2/yr (40%). The total area of the hyperintense lesions on the initial T2-weighted images showed a weak correlation with the Expanded Disability Status Scale score at entry (Spearman rank correlation coefficient [SRCC] = 0.30; 0.02 < p < 0.05). The increase in disability showed a positive correlation (SRCC = 0.19) with the increase in hyperintense lesion load on the T2-weighted SE images, but this correlation did not reach statistical significance (p = 0.09), probably because of lack of clinical progression.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Limited duration of the effect of methylprednisolone on changes on MRI in multiple sclerosis.

Treatment with methylprednisolone reduces the duration and severity of clinical relapses in multiple sclerosis (MS), while reducing the number of gadolinium-enhancing lesions on T1-weighted MRI. We performed serial MRI imaging after methylprednisolone treatment to see whether suppression of enhancement persists and whether related abnormalities on T2-weighted images disappear at follow-up. Thirteen patients with definite MS received a total of 31 courses of methylprednisolone over an average period of 50 weeks. Gadolinium-enhanced MRI was obtained before and after treatment, then at monthly intervals, using a standardised repositioning and imaging protocol. Two experienced readers in conference defined the number of active (gadolinium-enhancing and new or enlarging nonenhancing) lesions. We detected 609 active lesions on 195 examinations. Directly after treatment the reduction in the number of enhancing lesions was 78%, indicating restoration of the BBB and suppression of inflammation. It was uncommon for a lesion which stopped enhancing to show enhancement on a subsequent examination. No beneficial effect was observed on the rate of disappearance of related abnormalities on T2-weighted images, indicating persistent change such as oedema, cellular infiltration or demyelination. Moreover, in 89% of cases, an increase in the number of active lesions was observed before new clinical activity, if any, was observed (on average 52% earlier). MRI enabled us to demonstrate that the duration of the effect of methylprednisolone treatment is temporary (on average 9.7 weeks).

Adult↗
PubMed1994

Follow-up study of MS patients treated with high-dose intravenous methylprednisolone.

In a longitudinal prospective study, we followed 56 patients (17 men, 29 women) with definite multiple sclerosis (MS), who were treated with high-dose intravenous methylprednisolone (IVMP), 10 consecutive days with 1000 mg IVMP daily. Mean follow-up period after entry was 2.6 years (range 1.7-3.5 yrs). All patients were treated because of a symptomatic deterioration. Independent of the disease courses (RR-relapsing remitting/CP-chronic progressive/CP+RR- mixed course), 65% of the 46 MS patients (30/46) showed a clinical improvement after the first IVMP course, expressed by a decrease in the EDSS rating (1.0 point or more). During the follow-up period 59 additional IVMP courses (range 0-5 courses per patient) were given; 8 patients were treated with a combination of cyclophosphamide and prednisone, because of strong continuous progression. During the follow-up period 19 patients (41%) showed an increase in the EDSS-rating (1.0 point or more) compared with the EDSS level just after the first IVMP; 22 patients (48%) had no changes in the EDSS-rating, and 5 patients (11%) showed a clinical improvement (decrease of 1.0 point or more). In the relapsing MS patients (RR and CP+RR, n = 38) mean relapse rate/patient/year prior to the first IVMP was 2.6, which significantly (p < 0.0001) decreased to 0.8 during the follow-up period. Statistically no significant difference was found between baseline EDSS and EDSS ratings after the follow-up period in relapsing MS patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Magnetic resonance evaluation of disease activity during pregnancy in multiple sclerosis.

We followed two women with MS during pregnancy by means of serial unenhanced MR imaging. On each follow-up image, we assessed the number of new or enlarging lesions. Both women showed a decrease in MR disease activity during the second half of pregnancy and a return of MR disease activity to prepregnancy levels in the first months postpartum. These findings support the view that pregnancy reduces disease activity in MS.

Adult↗
PubMed1993

Decreased vitamin B12 and folate levels in cerebrospinal fluid and serum of multiple sclerosis patients after high-dose intravenous methylprednisolone.

Twenty-one patients (15 women, 6 men) with definite multiple sclerosis (MS) were treated with 1000 mg intravenous methylprednisolone-succinate (MP) daily for 10 days. Before MP treatment there was a negative correlation (r = 0.59, P = 0.0084) between serum vitamin B12 and progression rate, defined as the ratio of the score on Kurtzke's Expanded Disability Status Scale and disease duration. A significant decrease was demonstrated in the cerebrospinal fluid (CSF) and serum levels of folate and in the CSF level of vitamin B12 after MP treatment. The decrease in serum B12 was not statistically significant. After MP treatment all median levels of vitamin B12 and folate were below the reference medians. We hypothesize that low or reduced vitamin B12/folate levels found in MS patients may be related to previous corticosteroid treatments. Otherwise a more causal relationship between low vitamin B12/folate and MS cannot be excluded. Further studies may be required to clarify the vitamin B12 and folate metabolism in patients with MS.

Adult↗
PubMed1993

T-cell subsets in the cerebrospinal fluid and peripheral blood of multiple sclerosis patients treated with high-dose intravenous methylprednisolone.

To determine the effects of high-dose intravenous methylprednisolone (MP) on lymphocytes and lymphocyte subpopulations in the cerebrospinal fluid (CSF) and peripheral blood (PB) in multiple sclerosis (MS) patients, we studied 67 patients with definite MS treated with MP. They were classified according to the disease course: 32 chronic progressive (CP) patients, 25 relapsing-remitting (RR) patients, and 10 patients with a chronic progressive disease course accompanied by relapses and remissions (CP + RR). MS patients were treated with 1000 mgr intravenous MP daily for 10 consecutive days. Before and after MP treatment we simultaneously studied CSF and PB CD3+, CD4+, CD8+, CD20+, and Ia1+ cell subsets. Kurtzke's Expanded Disability Status Scale (EDSS) was used for clinical evaluation. Progression rate was defined as the ratio of EDSS to disease duration. Thirteen patients with lumbar disk herniation were investigated as controls. Before MP, we found in MS patients, especially in the CP group, significantly lower CD4+ T-cell percentages in the PB with respect to controls (p < 0.05). The percentage of CD4+ T-cells in the CSF of MS patients was significantly higher compared with PB (p = 0.0001), and tended to be higher than in controls (p = 0.072). The CSF mononuclear cell counts were significantly correlated with higher percentages of CSF CD3+ (r = 0.40) and CD4+ (r = 0.47) T-cells and lower CSF CD8+ (r = -0.33) T-cell percentages. B-cell percentages in the CSF were significantly elevated compared with controls for all MS groups. No relation could be obtained between T- or B-cell subsets and EDSS or progression rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Cortex Hormones↗
PubMed1992

The effects of high-dose methylprednisolone on gadolinium-enhanced magnetic resonance imaging and cerebrospinal fluid measurements in multiple sclerosis.

Blood-brain barrier (BBB) disruption is probably the first event in the lesion development in multiple sclerosis (MS). This stage can be visualized by gadolinium-enhanced magnetic resonance (MR) imaging of the brain. Serial MR imaging studies have indicated a continuous spectrum of disease activity with waxing and waning of acute lesions, even in clinically stable MS patients. High-dose intravenous methylprednisolone (MP) has a beneficial clinical effect; reduces gadolinium enhancement, indicating improvement of BBB integrity; and, in MS patients, decreases intrathecal immunoglobulin synthesis with reduction of cerebrospinal fluid (CSF) myelin basic protein (MBP). A correlative triad is noted between gadolinium enhancement, clinical improvement, and decrease of CSF MBP following MP treatment, indicating a relationship between restoration of BBB integrity, clinical improvement and decrease of myelin breakdown. It is not clear whether MP interferes primarily with the process of demyelination or reacts non-specifically with its mediators.

Gadolinium↗
PubMed1992

CSF myelin basic protein, IgG and IgM levels in 101 MS patients before and after treatment with high-dose intravenous methylprednisolone.

A total of 101 patients (62 women; 39 men) with definite MS were treated with 1000 mg methylprednisolone (MP) intravenously for 10 consecutive days. Immediately before and after MP treatment clinical scoring (Kurtzke's Expanded Disability Status Scale) and CSF analysis were performed. Before MP treatment CSF MBP, IgG and IgM immunoglobulin levels (CSF Ig, index and intrathecal synthesis) were significantly elevated. The mean CSF MBP levels were significantly higher in the relapsing-remitting (RR) and chronic progressive MS patients with relapses (CP + RR) than in the CP group without a RR disease course, respectively 2.1, 2.3 and 1.5 micrograms/l. A weak positive correlation was found between CSF MBP level and EDSS in the RR MS group (r = 0.34). CSF MBP was significantly correlated with IgM index (r = 0.36), IgM synthesis (r = 0.26), but not with the IgG levels. Therefore demyelination seems to be related to intrathecal IgM production. After MP treatment mean (median) EDSS decreased from 4.4 (4.0) to 3.3 (3.0). Except for Q albumin and IgM index, all CSF immunoglobulin levels decreased significantly after MP. The mean CSF MBP returned to reference values. In the RR group the decrease in CSF MBP was significantly correlated with the change in EDSS (r = 0.39). CSF MBP seems to be a good parameter for disease activity in relapsing MS. Following treatment CSF MBP was found to be related with the change in IgM index (r = 0.30). MP treatment reduces CSF MBP and intrathecal IgM in a similar way indicating a relation between these 2 parameters.

Adult↗
PubMed1992

A correlative triad of gadolinium-DTPA MRI, EDSS, and CSF-MBP in relapsing multiple sclerosis patients treated with high-dose intravenous methylprednisolone.

In a prospective study, we compared the number of gadolinium-DTPA (Gd-DTPA) enhancing lesions on MRI with the CSF and clinical findings before and after a total of 20 courses of high-dose intravenous methylprednisolone in relapsing multiple sclerosis patients. Before treatment, there was a significant correlation of Gd-DTPA enhancement (seen on 16 of 20 scans) and CSF myelin basic protein (MBP). If enhancement with Gd-DTPA represents inflammation and CSF-MBP indicates myelin breakdown, the amount of inflamed tissue should correlate with the amount of myelin being damaged. Clinical improvement occurred following 15 of 20 courses, and decrease of Gd-DTPA enhancement in 12 of 16 scans; the mean CSF-MBP level was the only CSF variable to return to reference values. There was a significant correlative triad of decrease in CSF-MBP, Gd-DTPA enhancement, and clinical disability. Thus, the clinical effect of methylprednisolone might be accompanied by a reduction of inflammation and myelin breakdown.

Adult↗
PubMed1992

Relapsing-remitting multiple sclerosis: sequential enhanced MR imaging vs clinical findings in determining disease activity.

OBJECTIVE: Sequential MR imaging frequently shows disease activity (clinically silent new brain lesions) in subgroups of patients with multiple sclerosis and therefore is valuable in monitoring the effects of treatment. Monitoring of disease activity in patients being treated for relapsing-remitting multiple sclerosis will increase in importance as new and safe therapies are developed. We studied sequential enhanced MR images of patients with early relapsing-remitting multiple sclerosis to define the MR features that indicate disease activity in this subgroup of patients and to compare MR imaging and clinical findings for this purpose. SUBJECTS AND METHODS: Seven patients with relapsing-remitting definite multiple sclerosis were examined monthly for 4-12 months. For each image, a standard repositioning protocol consisting of three images was used to ensure reproducibility of axial (double oblique) image planes, planned according to internal landmarks. A total of 58 unenhanced T2-weighted and enhanced T1-weighted MR images were obtained. RESULTS: MR images showed new enhancing lesions in six of the seven patients. On 25 (43%) of the 58 enhanced T1-weighted MR images, a total of 50 new enhancing lesions were observed, and on one image a reenhancing lesion was seen. The unenhanced T2-weighted images showed corresponding abnormalities for 92% of the new enhancing lesions. At follow-up, most lesions (86%) were enhanced on only one occasion: 4% were enhanced on more than two consecutive monthly MR examinations. Forty-nine percent of the lesions seen on T2-weighted images "disappeared" (beyond the resolution of the imaging system) after a mean follow-up of 3.5 months, especially lesions that were initially smaller than 5 mm. During the study, only five clinical relapses occurred in three patients (all at times when MR images showed contrast-enhancing lesions), and fixed disability did not increase. On 21 additional occasions, MR images showed new enhancing or reenhancing lesions in patients who were clinically stable at the time (4.2 times more clinically silent disease activity). CONCLUSION: Our results suggest that contrast-enhanced MR imaging is more sensitive than clinical monitoring for detecting new disease activity in patients with relapsing-remitting multiple sclerosis and that MR imaging might be useful in the evaluation of therapeutic regimens.

Adult↗
PubMed1991

Sensory axonopathy in hereditary distal spinal muscular atrophy.

A girl of 14 year is presented with a distal spinal muscular atrophy (SMA) with autosomal recessive inheritance. The technical findings are in agreement with the diagnosis. Light microscopical examination of sural nerve biopsy, including teased fiber studies and morphometry, showed no abnormalities. Electron microscopical investigation however demonstrated axonal pathology. The question arises if distal SMA is a distal axonopathy mainly of motor nerves, but to some extent also of sensory nerves.

Adolescent↗
PubMed1991

Recurrent prolonged coma due to basilar artery migraine. A case report.

A 25 year old patient presented with recurrent prolonged episodes of life-threatening coma varying from 3 to 10 days. The clinical recovery was slow. The history and technical examinations led to the diagnosis of basilar artery migraine (BAM). The etiology of the coma episodes is thought to be related to ischemic dysfunction of the rostral part of the brainstem due to severe spasm of the basilar artery demonstrated by arteriography. Exceptional are the recurrent prolonged coma episodes of sudden onset, the severe spasm of the basilar artery, and the suppression-burst and FIRDA pattern on the EEG examinations during the coma episodes.

Adult↗