Factors affecting functional outcome in patients with nontraumatic spinal cord lesions after inpatient rehabilitation

OBJECTIVE

Patients with nontraumatic spinal cord lesions account for between one fourth and one half of all spinal cord injuries. In the management of this group of patients, an understanding of factors influencing functional improvement is essential to help define the most appropriate rehabilitation programme. Although it is possible to predict accurately the functional outcome for an individual patient with a complete traumatic spinal cord injury, few studies have looked at prognostic factors in patients with nontraumatic spinal cord disease. The aim of this study was to determine which, and how well, factors assessed on admission to a rehabilitation unit relate to functional improvement in this group.

METHODS

The study sample consists of 100 patients with an incomplete nontraumatic spinal cord lesion who underwent inpatient neurorehabilitation. Possible prognostic factors were sought by identifying those variables with a significant difference in the Functional Independence Measure (FIM) motor change score above and below the median. A step-wise multiple regression analysis was then performed to determine which variables influenced functional outcome.

RESULTS

Patients with larger functional gains had significantly lower disability scores on admission, a shorter time between symptom onset and rehabilitation, and a longer length of stay. They were more likely to have a cervical lesion and evidence of neurologic recovery. Multiple regression analysis demonstrated that the FIM motor score on admission and the time between symptom onset and rehabilitation predicted 54% of the variance of the FIM motor score gain.

CONCLUSIONS

This finding suggests that early rehabilitation is an important factor in securing a good outcome.

Gap junction proteins in inhibitory neurons of the adult barrel neocortex

Recent studies indicate that electrical coupling among cortical neurons may persist throughout development; electrophysiological recordings made in cortical slices from young rats reveal that numerous GABAergic neurons are electrically coupled. To determine whether these in vitro findings reflect an inhibitory neural circuit that could be functionally relevant in vivo in adult rodents, we sought to identify whether inhibitory, parvalbumin-containing neurons of the mature cortex express gap junction proteins. Immunohistochemistry was used to examine the laminar distribution of the gap junction-forming proteins connexin 32 (Cx32), connexin 36 (Cx36) and connexin 43 (Cx43) in the somatosensory cortex of the adult mouse. Double labeling immunofluorescence identified Cx32, Cx36 and Cx43 in cortical neurons that were immunoreactive (-ir) for the neuronal markers neurofilament 145 kDa and neuronal nuclei (NeuN). Parvalbumin-ir neurons throughout the cortical laminae were labeled with Cx32-ir, Cx36-ir and Cx43-ir. Stereological methods were used to quantify the extent of parvalbumin colocalization with connexins. Analysis indicated that approximately 40% of parvalbumin-ir neurons were double labeled with either Cx32-ir or Cx43-ir, and approximately 50% of parvalbumin-ir neurons were double labeled with Cx36. These findings establish an anatomical substrate for widespread electrical coupling of neurons in somatosensory cortex and suggest that gap junctions among inhibitory interneurons may persist into adulthood, providing an important mechanism for neuronal communication.

Integrated care pathways: outcome from inpatient rehabilitation following nontraumatic spinal cord lesion

BACKGROUND

Integrated care pathways (ICPs) map the predicted course of an episode of patient care. They detail the expected interventions during the episode and document departures from the expected pathway (variance). This study describes the use of an ICP to audit the rehabilitation of patients with nontraumatic spinal cord injury admitted between 1997 and 1999.

METHODS

The ICPs and outcomes of 85 patients with nontraumatic spinal cord injury admitted to the Neurorehabilitation Unit at the National Hospital for Neurology and Neurosurgery, Queen Square, London were analysed. Data extracted included diagnosis, level of the lesion and duration of stay. The numbers and categories of goals and the rates of goal achievement were extracted and the variance patterns analysed.

RESULTS

An average of 28 patients were admitted each year. The level of disability on admission and the duration of stay decreased over the three-year period, while the average patient age increased from 48 to 54 years. None of these changes were statistically significant. On average each patient had three new goals set each week. Ninety per cent of all goals were achieved; this was not dependent on the category of goal. Sixteen patients (19%) accounted for 58% of all nonachieved goals. These patients tended to have acute-onset disability. The number of variances fell from 15 to 7 over the three-year period.

CONCLUSIONS

The pathway enables monitoring of the rehabilitation process. As the Unit becomes more experienced there is a trend to shorter, more focused admissions with fewer variances. Specific groups of patients with particular needs can be identified. Future patients benefit from closure of the 'audit loop' and the implementation of clinical change based on information obtained from the ICP.

T1 histograms of normal-appearing brain tissue are abnormal in early relapsing-remitting multiple sclerosis

OBJECTIVE

To use both whole-brain and normal-appearing brain tissue (NABT) T1 relaxation time histograms to investigate abnormalities in early relapsing-remitting (RR) multiple sclerosis (MS).

BACKGROUND

In patients with established MS, both lesions and NABT exhibit an increase in T1 relaxation time. By using T1 histogram analysis, it is hoped that such changes in early disease can be detected.

METHOD

Twenty-seven patients and 14 age- and sex-matched controls underwent magnetic resonance imaging (MRI) of the brain, which included the following sequences: 1) proton density (PD)- and T2-weighted fast spin echo (FSE) to measure T2 lesion load, 2) PD- and T1-weighted gradient echos from which T1 relaxation was calculated, and 3) T1-weighted SE imaging pre- and post-triple dose (0.3 mmol/kg) gadolinium (Gd-DTPA) to measure T1 hypointense and gadolinium-enhancing lesion loads, respectively. All patients had RR MS with disease duration <3 years (median 1.7 years). Statistical parametric mapping (SPM) 99 was used to segment brain from cerebrospinal fluid (CSF), and lesions were segmented using a local thresholding technique.

RESULTS

Both whole-brain and NABT histograms were abnormal for all six T1 histogram parameters that were measured. For NABT, the mean T1 was 1,027 (+/- 74) ms in patients and 969 (+/- 41) ms in controls (p=0.003). There was little difference between the global and NABT histograms, which indicates that most of the whole-brain histogram abnormality derives from normal-appearing tissues. There was a correlation between the Nine-Hole Peg Test and NABT T1 measures.

CONCLUSION

There are widespread abnormalities of NABT in early RR MS, which were sensitively detected by T1 relaxation time histogram analysis. As such, T1 histogram analysis appears promising for studying the natural history of early RR MS, and in the monitoring of response to treatment

Quantitative 1H MRS imaging 14 years after presenting with a clinically isolated syndrome suggestive of multiple sclerosis

clinically isolated syndromes (CIS) are events suggestive for emerging multiple sclerosis (MS). A majority of patients develop MS within months or years whilst others remain clinically isolated. The goal of this study was to investigate whether biochemical metabolites detectable by 'H magnetic resonance spectroscopy (MRS) may serve to distinguish between these two groups. We investigated 41 patients 14 years after presentation with a CIS and 21 controls with combined quantitative short echo 'H MRS and magnetic resonance imaging (MRI) and assessed disability according to the Expanded Disability Status Scale (EDSS). At follow-up, 32 had developed MS, and 9 still had CIS. Compared with controls, MS patients demonstrated significantly higher concentrations of myo-inositol (Ins) in normal appearing white matter (NAWM) and lesions. Lesions also demonstrated a reduced N-acetyl-aspartate (NAA) level and an increase in choline-containing compounds (Cho). The NAWM Ins concentration was correlated with EDSS (r = 0.48, p = 0.005). MS normal appearing cortical grey matter (CGM) exhibited a decreased NAA. Patients who remained CIS did not differ significantly from controls in any MRS measure. Metabolite changes in normal appearing white and grey matter in MS indicate diffuse involvement of the entire MS brain, which was not seen in the persisting CIS patients. Elevated Ins in MS NAWM appeared functionally relevant It may indicate glial cell proliferation or gliosis.

Two-year follow-up study of primary and transitional progressive multiple sclerosis

This study documents changes in clinical and magnetic resonance imaging (MRI) characteristics in a large cohort of patients with primary and transitional progressive multiple sclerosis (PP and TPMS) over 2 years. Patients with PPMS and TPMS were recruited from six European centres and underwent clinical and MRI examination at three time points: baseline, year one and year two. Of the 190 patients recruited clinical data were available on 125 patients (66%, five centres) and MRI data were available on 113 patients (59%, four centres) at 2 years. Significant increases were seen in T2 load and T1 hypointensity, while brain and cord volume decreased. In PPMS significantly higher lesion loads were found in those who presented with non-cord syndromes when compared to cord presentation and there was a trend to greater brain atrophy in those who deteriorated clinically over the course of the study compared to those who remained stable. Significant cord atrophy was only seen in those with a cord presentation. Measurable changes in MRI parameters can be detected in PPMS patients over a relatively short period of time. MRI quantification is likely to be useful in elucidating disease mechanisms in PPMS and in the execution of clinical trials.

Brain atrophy in clinically early relapsing-remitting multiple sclerosis

Brain atrophy measured by MRI is a potentially useful tool for monitoring disease progression in multiple sclerosis. The location, extent and mechanisms of brain atrophy in early disease are not well documented. Using quantitative MRI, this study investigated whole brain, grey and white matter atrophy in clinically early relapsing-remitting multiple sclerosis and its relationship to lesion measures. Data came from 27 normal control subjects (14 females and 13 males, mean age 36.1 years) and 26 subjects with clinically definite multiple sclerosis (18 females and eight males, mean age 35.1 years, mean delay from first symptom to scan 1.8 years, median Expanded Disability Status Scale score 1.0). All had three-dimensional fast spoiled gradient recall (3D FSPGR), T(1)-weighted pre- and post-gadolinium-enhanced and T(2)-weighted scans. The 3D FSPGR images were automatically segmented into grey and white matter and cerebrospinal fluid using SPM99. 3D FSPGR hypo-intense, T(2) hyper-intense, T(1) hypo-intense and T(1) post-gadolinium-enhancing lesion volumes were determined by semi-automatic lesion segmentation. The SPM99 output was combined with the 3D FSPGR lesion segmentations to quantify tissue volumes as fractions of total intracranial volumes, producing values for the brain parenchymal fraction (BPF), white matter fraction (WMF) and grey matter fraction (GMF). Comparing multiple sclerosis with control subjects, BPF, GMF and WMF were significantly reduced (P < 0.001 for all tissue fractions). Using Pearson correlations, T(2) hyper-intense and T(1) hypo-intense lesion volumes were inversely related to BPF (T(2) r = -0.78, P < 0.001; T(1) r = -0.59, P = 0.002) and GMF (T(2) r = -0.73, P < 0.001; T(1) r = -0.53, P = 0.006), but not WMF (T(2) r = -0.30, P = 0.134; T(1) r = -0.26, P = 0.199). T(1) post-gadolinium-enhancing lesion volumes were not correlated with any fractional volumes. These results indicate that significant brain atrophy, affecting both grey and white matter, occurs early in the clinical course of multiple sclerosis. The lack of correlation between lesion load measures and WMF suggests that pathological changes in white matter may occur by mechanisms which are at least partly independent from overt lesion genesis in early multiple sclerosis.

Clinical-MRI correlations in a European trial of interferon beta-1b in secondary progressive MS

BACKGROUND

The recently completed placebo-controlled multicenter randomized trial of interferon beta-1b (Betaferon) in 718 patients with secondary progressive MS shows significant delay of disease progression and reduction of relapse rate. This study provides an opportunity to assess the level of relationship between clinical and MRI outcomes in this cohort of patients with secondary progressive MS.

METHODS

Brain T2-weighted lesion volume was measured annually in all available patients, with visual analysis to identify any new or enlarging (active) T2 lesions at each annual time point. A subgroup of 125 patients had monthly gadolinium-enhanced, T1-weighted imaging at months 0 to 6 and 18 to 24. Relapses were documented and expanded disability status scale (EDSS) was measured every 3 months.

RESULTS

For the annual MRI outcomes, a significant but modest correlation was identified between the change in T2 lesion volume from baseline to the final scan and the corresponding change from baseline in EDSS (r = 0.17, p < 0.0001). There were significant correlations between the cumulative number of active T2 lesions and 1) change in EDSS (r = 0.18, p < 0.0001) and 2) relapse rate (r = 0.24, p < 0.0001). In the subgroup of 125 patients undergoing monthly imaging, MRI lesion activity was correlated with relapse rate over months 0 to 24 (r = 0.24, p = 0.006) but not with change in EDSS.

CONCLUSIONS

These results confirm that the clinical-MRI relationships previously identified in relapsing-remitting MS still are apparent in the secondary progressive phase of the disease and support the use of MRI as a relevant outcome measure. In view of the relatively modest nature of the correlations, it seems unwise to rely on such MRI measures alone as primary efficacy variables in secondary progressive MS trials.

The effect of IFNbeta-1b on the evolution of enhancing lesions in secondary progressive MS

BACKGROUND

After the resolution of contrast enhancement, the majority of new MS lesions become isointense with surrounding white matter on T1-weighted MRI. Less commonly, a hypointense T1 lesion develops, representing the development of more severe focal tissue damage. Interferon beta (IFNbeta) reduces both the number of new enhancing lesions and the duration of contrast enhancement.

OBJECTIVE

To determine if IFNbeta affects the degree of tissue damage within new lesions and if its effects are related to lesion size.

METHODS

One hundred twenty-five patients with secondary progressive MS from seven European sites were randomized to receive either IFNbeta-1b or placebo. Monthly, contrast-enhanced T1-weighted MR images were acquired at baseline, at months 1 to 6, and at months 19 to 24. The size of all new enhancing lesions developing between months 1 and 6 was recorded and their appearance at follow-up documented.

RESULTS

In the first 6 months, fewer new enhancing lesions occurred in the IFNbeta-1b arm. This difference was greater for small (70% decrease) than for large (46% decrease) lesions. Hypointense T1 lesions were more likely to form from large (25%) than from small (9%) enhancing lesions in both treatment arms. Patients taking IFNbeta-1b developed fewer hypointense T1 lesions; however, the proportion of enhancing lesions developing into hypointense T1 lesions was similar in both arms.

CONCLUSION

IFNbeta-1b reduced the number of new enhancing lesions, with a greater effect on small lesions. However, when a new enhancing lesion did become established, treatment with IFNbeta-1b did not alter its subsequent course.

Interferon-beta1b in the treatment of secondary progressive MS: impact on quality of life

BACKGROUND

The recent randomized, controlled trial of interferon-beta1b (IFN-beta1b) in 718 patients with secondary progressive MS (SP-MS) demonstrated a significant effect on the development of disability as evaluated by the physician. Its effect on patient-reported health-related quality of life (HrQoL) is reported herein.

METHODS

In this multicenter, double-blind, randomized, placebo-controlled trial, outpatients with SP-MS scoring between 3.0 and 6.5 on the Expanded Disability Status Scale received either 8 x 10(6) IU of IFN-beta1b or placebo for up to 3 years. A range of outcomes was measured, including HrQoL, which was assessed using the Sickness Impact Profile (SIP), a self-report questionnaire validated for use in MS. Measurements were undertaken at baseline and at 6-monthly intervals thereafter for 36 months.

RESULTS

A slight positive effect on the HrQoL of the IFN group in comparison with the placebo group was found, which reached significance in the physical scale of the SIP at 6 and 12 months and at last visit. There was moderate correlation between physician-assessed evaluation of change and patient-reported change.

CONCLUSIONS

IFN-beta1b may delay sustained deterioration in patient-reported HrQoL in SP-MS. Methods of interpreting change in HrQoL are currently insufficiently developed to determine how clinically important these changes are for this population.

A modified protocol to improve the detection of enhancing brain and spinal cord lesions in multiple sclerosis

By detecting focal blood-brain barrier (BBB) breakdown, gadolinium (Gd-DTPA) contrast-enhanced T1-weighted magnetic resonance imaging (MRI) allows assessment of inflammatory activity in multiple sclerosis (MS) and provides a sensitive means of monitoring immunomodulatory therapies in exploratory trials. Serial monthly studies were performed in eight relapsing-remitting and eight secondary progressive patients to assess new and more sensitive techniques for enhanced MRI. Brain and spine imaging was carried out at 1.5-T on two occasions 24-72 h apart using a conventional imaging protocol with T1-weighted MRI at single-dose (0.1 mmol/kg) Gd-DTPA and a potentially more sensitive "modified" protocol with T1-weighted MRI at triple-dose (0.3 mmol/kg) Gd-DTPA (with addition of delay and magnetisation transfer presaturation for brain imaging). For each MRI protocol the total numbers of enhancing lesions (97 paired studies) and new enhancing lesions (81 paired studies) were assessed. The total number of enhancing lesions seen was 347/75 on conventional brain/cord MRI respectively, and 754/123 on modified brain/cord MRI. The respective numbers of new enhancing lesions were 168/40 on conventional and 276/71 on modified scans. Smaller increases were seen in the proportion of active scans using the modified protocol. Sample size calculations showed no reduction in sample sizes required for a parallel group study but a reduced sample size for crossover studies using the modified protocol; the addition of cord to brain imaging did not improve power for either trial design. A combined modified brain and cord imaging protocol markedly improves the detection of areas of focal BBB leakage in MS and may be useful in selected natural history studies. The modified brain protocol reduces sample size requirements for crossover studies but not necessarily for parallel design trials.

The clinical and laboratory features of chronic sensory ataxic neuropathy with anti-disialosyl IgM antibodies

The clinical and laboratory phenotype of a paraproteinaemic neuropathy syndrome termed chronic sensory ataxic neuropathy with anti-disialosyl IgM antibodies is described in a series of 18 cases. Previous single case reports have outlined some features of this syndrome. All 18 cases were defined by the presence of serum IgM antibodies which react principally with NeuAc (alpha2-8)NeuAc(alpha2-3)Gal-configured disialosyl epitopes common to many gangliosides including GDlb, GD3, GTlb and GQlb. In 17 out of 18 cases, the serum contained benign IgM paraproteins, and in four of these cases at least two IgM paraproteins were present. The IgM antibodies were also cold agglutinins in 50% of cases. The clinical picture comprised a chronic neuropathy with marked sensory ataxia and areflexia, and with relatively preserved motor function in the limbs. In addition, 16 out of 18 cases had motor weakness affecting oculomotor and bulbar muscles as fixed or as relapsing-remitting features. When present in their entirety, these clinical features have been described previously under the acronym CANOMAD: chronic ataxic neuropathy, ophthalmoplegia, IgM paraprotein, cold agglutinins and disialosyl antibodies. This distribution of clinical features is reminiscent of Miller Fisher syndrome, in which acute-phase anti-disialylated ganglioside IgG antibodies are found. Clinical electrophysiology and nerve biopsy show both demyelinating and axonal features. A partial response to intravenous immunoglobulin and other treatments is reported in some cases.

Asymmetrical activation of human visual cortex demonstrated by functional MRI with monocular stimulation

We have demonstrated asymmetric activation patterns in the visual cortices of normal humans who have undergone functional MRI with monocular photic stimulation. The contralateral hemisphere is activated more strongly and to a greater spatial extent than the ipsilateral hemisphere when either eye is stimulated. This asymmetry can be explained by nasotemporal asymmetries which have been described in anatomical studies of the visual system in primates and humans. In part, the representation of the monocular crescent of the temporal hemifield of either eye, which exists only in the crossed projection, may explain this. In addition, within the binocular field, there is a biased crossed projection of nasal retinal ganglion cells which drive the contralateral ocular dominance columns in V1. Finally, the blind spot representation in the ipsilateral visual cortex may also contribute to the observed asymmetries. Our study may in effect provide a functional correlate of the anatomical asymmetries that have been observed in humans and animals.

Fatigue is not associated with raised inflammatory markers in multiple sclerosis

BACKGROUND

The pathogenesis of fatigue in patients with MS is poorly understood.

OBJECTIVE

To test the hypothesis that fatigue in MS is related to inflammatory disease activity as measured by systemic markers of inflammation.

METHODS

Fatigue as assessed by the Fatigue Questionnaire Scale (FQS) and Krupp's Fatigue Severity Scale (KFSS) was correlated with several inflammatory markers in 38 patients with MS (16 relapsing-remitting [RR; 7 of whom had benign MS), 9 secondary progressive [SP], 13 primary progressive [PP]). The markers included daily urinary neopterin excretion, a marker of interferon-gamma-activated macrophage activity, and serum C-reactive protein (CRP) and soluble intercellular adhesion molecule-1 (sICAM-1) levels. Urinary neopterin excretion was measured daily for 2 weeks.

RESULTS

No correlation was found between urinary neopterin excretion, CRP, or sICAM-1 and the fatigue scores. However, patients with a raised serum CRP level had higher KFSS, but not FQS, scores than patients with normal CRP levels (KFSS, 50 +/- 8 vs 41 +/- 14, p = 0.05; FQS, 13 +/- 4 vs 11 +/- 5, p = NS). When assessed using the FQS, patients with RR and SP MS were more fatigued than patients with PP MS (RR = 12.5 [4 to 23] vs SP = 13 [8 to 18] vs PP = 9 [7 to 14], p = 0.02). The patients with benign MS were as fatigued as patients with nonbenign disease.

CONCLUSION

The pathogenesis of fatigue in MS is complex and does not appear to be directly related to systemic markers of inflammatory disease activity. Interestingly, patients with PP MS were less fatigued than patients with RR disease.

Evidence-based measurement: which disability scale for neurologic rehabilitation?

OBJECTIVE

To compare the 10-item Barthel Index (BI), 18-item Functional Independence Measure (FIM), and 30-item Functional Independence Measure + Functional Assessment Measure (FIM+FAM) as measures of disability outcomes for neurologic rehabilitation.

METHODS

A total of 149 inpatients from two rehabilitation units in South England specializing in neurologic disorders were studied. Traditional psychometric methods were used to evaluate and compare acceptability (score distributions), reliability (internal consistency, intrarater reproducibility), validity (concurrent, convergent and discriminant construct), and responsiveness (standardized response mean).

RESULTS

All three rating scales satisfied recommended criteria for reliable and valid measurement of disability, and are acceptable and responsive in this study sample. The FIM and FIM+FAM total scales are psychometrically similar measures of global disability. The BI, FIM, and FIM+FAM motor scales are psychometrically similar measures of physical disability. The FIM and FIM+FAM cognitive scales are psychometrically similar measures of physical disability.

CONCLUSIONS

In the sample studied, the BI, FIM, FIM+FAM have similar measurement properties, when examined using traditional psychometric analyses. Although instruments with more items and item response categories generate more qualitative information about an outcome, they may not improve its measurement. Results highlight the importance of using recognized techniques of scale construction to develop health outcome measures.

A new test of memory for multiple sclerosis I: format development and stimuli design

Memory tests were often developed for healthy populations. The accuracy of these measures is reduced when administered to patients with neurological diseases, who may experience physical and/or cognitive symptoms. Also, methodological factors, for example, spanning the ability spectrum, and content/format artefacts, may contribute to a decline in test precision. The aim of this study was to develop a new test of memory, which addresses these issues. The new memory test comprises assessments of recall, paired association, and recognition, at a Task Familiarisation stage and two difficulty levels, for both the verbal and spatial modalities. It was administered to 85 healthy individuals and 100 patients with multiple sclerosis (MS). All patients were able to attempt each task of the new assessment and there was no influence of visual integrity or manual dexterity on memory test performance, supporting the applicability of the tasks to patients with multiple sclerosis. Both the standardisation and validation samples demonstrated a wide range of scores on each section of the new test suggesting that the measure spanned an acceptably broad range of abilities. It seems probable, therefore, that the new assessment offers a more exact measure of verbal and spatial recall, paired association, and recognition memory.

The five item Barthel index

OBJECTIVES

Routine data collection is now considered mandatory. Therefore, staff rated clinical scales that consist of multiple items should have the minimum number of items necessary for rigorous measurement. This study explores the possibility of developing a short form Barthel index, suitable for use in clinical trials, epidemiological studies, and audit, that satisfies criteria for rigorous measurement and is psychometrically equivalent to the 10 item instrument.

METHODS

Data were analysed from 844 consecutive admissions to a neurological rehabilitation unit in London. Random half samples were generated. Short forms were developed in one sample (n=419), by selecting items with the best measurement properties, and tested in the other (n=418). For each of the 10 items of the BI, item total correlations and effect sizes were computed and rank ordered. The best items were defined as those with the lowest cross product of these rank orderings. The acceptability, reliability, validity, and responsiveness of three short form BIs (five, four, and three item) were determined and compared with the 10 item BI. Agreement between scores generated by short forms and 10 item BI was determined using intraclass correlation coefficients and the method of Bland and Altman.

RESULTS

The five best items in this sample were transfers, bathing, toilet use, stairs, and mobility. Of the three short forms examined, the five item BI had the best measurement properties and was psychometrically equivalent to the 10 item BI. Agreement between scores generated by the two measures for individual patients was excellent (ICC=0.90) but not identical (limits of agreement=1.84+/-3.84).

CONCLUSIONS

The five item short form BI may be a suitable outcome measure for group comparison studies in comparable samples. Further evaluations are needed. Results demonstrate a fundamental difference between assessment and measurement and the importance of incorporating psychometric methods in the development and evaluation of health measures.

Does adding MS-specific items to a generic measure (the SF-36) improve measurement?

OBJECTIVE

The 36-item Short Form Health Survey Questionnaire (SF-36) is a widely used generic health status measure. Recently it has been adapted to produce a disease-specific measure for MS-the 54-item Multiple Sclerosis Quality of Life Scale (MSQOL-54)-composed of five unchanged SF-36 scales; three altered SF-36 scales (one item added to each scale); and five new scales incorporating 15 additional items. This study evaluates the impact of these additions by comparing the measurement properties of the MSQOL-54 with the SF-36.

METHODS

A total of 150 patients with MS, representing a broad spectrum of disease severity, completed a range of questionnaires, which included the MSQOL-54 (from which the SF-36 score was computed). Of these, 44 people completed the measures before and after inpatient rehabilitation to evaluate responsiveness. Standard psychometric methods were used to evaluate the measurement properties.

RESULTS

The measurement properties of the unchanged scales, inevitably, remain identical. Those of the three altered scales are virtually identical. Of the five new scales, the validity of the two sexual scales is questioned because of the high percentage of missing data, and the validity of the overall quality-of-life scale is limited as demonstrated by the low to moderate correlations with other related and unrelated measures. Responsiveness of the new scales also appears limited.

CONCLUSION

Modifying existing measures by simply adding clinically chosen items may not be as useful as anticipated in improving the measurement properties of an instrument.

T(1) hypointense lesions in secondary progressive multiple sclerosis: effect of interferon beta-1b treatment

Recently, the clinical efficacy of interferon beta-1b (IFNbeta-1b) was demonstrated for secondary progressive (SP) multiple sclerosis in a European multicentre study. We evaluated the effect of IFNbeta-1b treatment on the rate of development of hypointense T(1) MRI lesions, a putative marker of axonal damage. Unenhanced T(1)-weighted images were obtained in a subgroup of 95 multiple sclerosis patients from five centres at 6-month intervals; this subgroup was similar to the total study population for all demographic, clinical and MRI parameters. An experienced observer blinded to the clinical data and treatment allocation measured volumes. The median baseline lesion load for hypointense T(1) lesions was 5.1 cm(3) for placebo-treated and 4.9 cm(3) for IFNbeta-1b-treated patients (P = 0.56). Placebo-treated patients showed an increase in T(1) lesion load by a median of 14% per year (P = 0.0002 compared with baseline); this was reduced to 7.7% per year in the IFNbeta-1b-treated patients (P = 0.003 versus placebo). In the IFNbeta-1b arm there was a statistically significant correlation between absolute change in Expanded Disability Status Scale scores and T(1) lesion load by month 36 (r = 0.38, P = 0.0015). In patients with SP multiple sclerosis, IFNbeta-1b treatment reduces the development of hypointense T(1) lesions, suggesting that reduced axonal damage in lesions may play a part in the beneficial effect that is observed clinically.

T1 hypointensity of the spinal cord in multiple sclerosis

It has recently been shown in multiple sclerosis (MS) that the volume of T1 hypointense lesions in the brain explains more of the variance in disability amongst patients than T2 lesion volume. T1 hypointense lesions may therefore represent areas of underlying pathology likely to be of functional significance, such as axonal loss. The spinal cord is a common area of involvement in MS and its dysfunction is likely to be responsible for much of the motor disability seen. Hence it serves as a useful model by which to examine the functional relevance of differing imaging sequences. We have therefore examined the relationship between T1 signal intensity in the spinal cord and disability in 60 patients with MS. We have also examined the relationship between T1 signal intensity and atrophy of the cord, as the latter is another potential marker of axonal loss. Sixty patients with MS underwent spinal cord imaging with a T1 weighted sequence to acquire axial sections of the cord at the C2 level. These sections were histogram matched to allow comparison of image intensity and a manual outlining technique was applied from which the mean cord intensity was calculated. Within the patient group there was a significant relationship between T1 signal intensity and disability as measured with the EDSS (r = -0.4, p < 0.005) and also between T1 signal intensity and atrophy (r = 0.36, p < 0.005). This study demonstrates that disability and atrophy are associated with a generalised reduction in cord signal on T1 weighted images. A lower T1 signal intensity in the spinal cord may be more pathologically specific than T2 hyperintensity and may represent underlying axonal loss, although gliosis and predominant white matter atrophy are alternative possibilities.

Serum inflammatory markers and clinical/MRI markers of disease progression in multiple sclerosis

The aim of this study was to assess whether mean serum levels of inflammatory markers when measured serially correlate with disease progression or putative MRI markers of axonal loss in a cohort of well-characterised multiple sclerosis (MS) patients. Serial serum levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1), nitric oxide metabolites nitrate and nitrite (NOx), C-reactive protein (CRP), neopterin and tumour necrosis factor alpha (TNF-alpha) were measured in 29 MS patients, 13 with a relapsing remitting (RR) and 16 with a secondary progressive (SP) course, who were participating in a phase II clinical trial of anti-CD4 therapy. Short-term whole blood stimulated TNF-alpha production was also measured. Patients were studied 12 times over an 18-month period. MRI variables included the number and volume of Gd-enhancing lesions and the change in T2-hyperintense, T1-hypointense lesions and cerebral volume between the baseline and exit studies. Disease progression required a sustained change in the EDSS. There was no correlation between mean levels of inflammatory markers over the study period and disease progression or changes in any of the MRI measures. However, mean sICAM-1 levels from the first 6 months of the study were higher in patients who progressed during the study than in those that did not (443 (SD439) vs. 235 (SD162) ng/mL, p=0.05). Mean levels of NOx were significantly higher in patients with RR MS than in patients with SP disease (59.1 micromol/L (SD 12.8) vs. 48.7 micromol/L (SD 11.9), p=0.02). Patients with either a single relapse or no relapse had significantly higher NOx levels than to patients with multiple relapses during the 18 month follow-up (59.0 micromol/L (SD 12.3) vs. 47.9 micromol/L (SD 12.0), p=0.02). The mean levels of the other inflammatory markers did not correlate with disease course or relapse-rate. Serum levels of many inflammatory markers do not correlate with short-term disease progression. Some of the data suggest that the effects of inflammation on disease progression are delayed. In addition raised levels of serum nitric oxide metabolites are associated with a lower number of clinical relapses and a non-progressive disease course. These findings, although preliminary, pose interesting questions on the role of nitric oxide in the pathogenesis of MS. Inducible NO production in the early stages of the disease may be beneficial.

Altered middle lamella homogalacturonan and disrupted deposition of (1-->5)-alpha-L-arabinan in the pericarp of Cnr, a ripening mutant of tomato

Cnr (colorless non-ripening) is a pleiotropic tomato (Lycopersicon esculentum) fruit ripening mutant with altered tissue properties including weaker cell-to-cell contacts in the pericarp (A.J. Thompson, M. Tor, C.S. Barry, J. Vrebalov, C. Orfila, M.C. Jarvis, J.J. Giovannoni, D. Grierson, G.B. Seymour [1999] Plant Physiol 120: 383-390). Whereas the genetic basis of the Cnr mutation is being identified by molecular analyses, here we report the identification of cell biological factors underlying the Cnr texture phenotype. In comparison with wild type, ripe-stage Cnr fruits have stronger, non-swollen cell walls (CW) throughout the pericarp and extensive intercellular space in the inner pericarp. Using electron energy loss spectroscopy imaging of calcium-binding capacity and anti-homogalacturonan (HG) antibody probes (PAM1 and JIM5) we demonstrate that maturation processes involving middle lamella HG are altered in Cnr fruit, resulting in the absence or a low level of HG-/calcium-based cell adhesion. We also demonstrate that the deposition of (1-->5)-alpha-L-arabinan is disrupted in Cnr pericarp CW and that this disruption occurs prior to fruit ripening. The relationship between the disruption of (1-->5)-alpha-L-arabinan deposition in pericarp CW and the Cnr phenotype is discussed.

Acute asthma exacerbations and air pollutants in children living in Belfast, Northern Ireland

The incidence of childhood asthma, a common condition, is on the rise worldwide. Despite reductions in the emission of urban smoke, traffic pollution is now a major worldwide problem. Belfast, Northern Ireland, is an old industrial city with major pollution problems. In this study, the authors investigated the rates of acute asthma admissions to Belfast's major children's emergency department. The admissions were studied, relative to day-to-day fluctuations in thoracic particulate matter, sulfur dioxide, nitrogen dioxide, nitric oxide, oxides of nitrogen, ozone, carbon monoxide, benzene, temperature, and rainfall. Daily admissions for acute asthma at the emergency department of the Royal Belfast Hospital and average daily pollution were recorded for the 3-yr period between January 1, 1993, and December 31, 1995. The authors used Poisson regression to assess independent association(s). Individually, small associations were seen for thoracic particulate matter (relative risk = 1.10), sulfur dioxide (relative risk = 1.09), nitrogen dioxide (relative risk = 1.11), nitric oxide (relative risk = 1.07), oxides of nitrogen (relative risk = 1.10), carbon monoxide (relative risk = 1.07), and benzene (1.14); no associations were noted between meteorological factors (temperature and rainfall) or ozone and asthma emergency-department admissions. The authors adjusted for the aforementioned parameters, and benzene level was the only variable associated independently with asthma emergency-department admissions in children. Benzene may be a more reliable method of measuring exposure to vehicle exhaust emissions than measurements of other pollutants.

Magnetization transfer imaging in patients with clinically isolated syndromes suggestive of multiple sclerosis

BACKGROUND AND PURPOSE

In patients with multiple sclerosis (MS), reduced magnetization transfer ratios (MTRs) have been reported in white matter that appears normal on studies obtained with conventional imaging techniques. The stage in the disease when this first becomes detectable is unclear. The purpose of this study was to measure the MTR of normal-appearing white matter (NAWM) and lesions in patients with clinically isolated syndromes (CIS), many of whom are at the earliest stages of MS, and to determine the prognostic value of any observed changes.

METHODS

Twenty-seven CIS patients and 13 matched control subjects were studied. The mean MTR was measured from 10 regions of NAWM and, when present, from lesions. The patients were followed-up clinically for a median of 12 months.

RESULTS

There was no significant difference in the mean MTR between NAWM in control subjects (38.5% units) and that in CIS patients (38.4% units). After 12 months' follow-up, MS developed in 26% of the patients. The MTR of NAWM in these patients did not differ from that of the other patients or the control subjects.

CONCLUSION

The reduced MTR in NAWM, described in established MS, was not detectable in patients with CIS. MTR did not provide prognostic information for this short period of follow-up.

Investigation of MS normal-appearing brain using diffusion tensor MRI with clinical correlations

OBJECTIVE

To quantitatively investigate water diffusion changes in normal-appearing white matter (NAWM) and gray matter in patients with MS, and to evaluate whether these changes are correlated with clinical disability and disease duration.

BACKGROUND

Diffusion tensor imaging provides quantitative information about the magnitude and directionality (anisotropy) of water diffusion in vivo and detects pathologic changes in MS brain tissue.

METHODS

Diffusion tensor imaging was performed in 39 patients with MS and in 21 age-matched control subjects. Quantitative indices, including fractional anisotropy, volume ratio, and mean diffusivity, were obtained in 30 regions of interest located in normal-appearing basal ganglia, cerebellar gray matter, and supratentorial and infratentorial NAWM.

RESULTS

Patients with MS showed significantly reduced anisotropy and a trend toward increased diffusivity in the infratentorial and supratentorial NAWM, and significantly increased anisotropy in the basal ganglia. In all patients with MS, both fractional anisotropy and mean diffusivity in the cerebral peduncles were inversely correlated with the Expanded Disability Status Scale and pyramidal functional scores. In patients with relapsing-remitting MS, there was a strong correlation between Expanded Disability Status Scale score and fractional anisotropy in both supratentorial and infratentorial NAWM. In primary and secondary progressive MS, disease duration correlated strongly with mean diffusivity in infratentorial NAWM and fractional anisotropy in the cerebral peduncles, respectively.

CONCLUSION

The most striking finding of decreased fractional anisotropy in supratentorial and infratentorial NAWM and increased fractional anisotropy in basal ganglia may result from axonal degeneration due to fiber transection in remote focal lesions. Diffusion tensor imaging indices, in particular fractional anisotropy, appear sensitive to structural damage in NAWM that is associated with disability and progression in MS.

Water diffusion is elevated in widespread regions of normal-appearing white matter in multiple sclerosis and correlates with diffusion in focal lesions

Pathological changes in the normal-appearing white matter in multiple sclerosis are well recognised, but their relationship to pathology in focal lesions is not well understood. Magnetic resonance diffusion imaging is sensitive to abnormalities in the integrity, size and geometry of water spaces in brain tissue. This study investigated the anatomical distribution of normal-appearing white matter diffusion abnormalities and their relationship to diffusion in focal lesions in multiple sclerosis (MS). The average apparent diffusion coefficient (ADCav) was measured by three-axis echoplanar diffusion imaging in normal-appearing white matter regions and lesions throughout the brain in 40 patients, and in white matter in 14 matched controls. The correlation between the ADCav in normal-appearing white matter and lesions was determined. In controls and patients, diffusion was highest in the corpus callosum. Patients had a higher mean ADCav than controls in widespread regions including the corpus callosum, cerebellar, temporal and occipital normal-appearing white matter. Mean normal-appearing white matter ADCav correlated strongly with mean lesion ADCav (r = 0.67, P < 0.001). This study demonstrates that water diffusion is elevated in widespread areas of normal-appearing white matter in MS, and is correlated with diffusion in lesions. These findings suggest that the pathogenetic mechanisms causing tissue damage in lesions and normal-appearing white matter are at least partly linked.

Measurement of spinal cord area in clinically isolated syndromes suggestive of multiple sclerosis

Atrophy of the spinal cord is known to occur in multiple sclerosis but the cause and the timing of its onset are not clear. Recent evidence suggests that atrophy may start to occur early in the disease. The aim was to determine whether atrophy of the spinal cord could be detected in vivo using MRI techniques, in patients presenting with a clinically isolated syndrome, which in many cases is the earliest clinical stage of multiple sclerosis. The cross sectional area of the spinal cord was measured in 43 patients presenting with a clinically isolated syndrome and 15 matched controls. T2 weighted imaging of the brain was also performed to determine the number and volume of high signal lesions consistent with disseminated demyelination. Both patients and controls were restudied after 1 year. The spinal cord area was significantly smaller in the 74% of patients with an abnormal brain MRI at presentation than in controls (mean areas 73.9 mm(2) and 78.1 mm(2) respectively, p=0.03). No significant difference was found in the spinal cord area between controls and patients with normal baseline brain imaging. The annual rate of change in patients did not differ significantly from controls. In conclusion, the finding of a smaller cord area in the subgroup of patients with clinically isolated syndrome with the highest risk of developing multiple sclerosis-that is, with an abnormal brain MRI, suggests that atrophy has developed in some patients with multiple sclerosis even before their first clinical symptoms. However, the lack of a detectable change in cord area over 1 year of follow up contrasts strikingly with the results of an earlier study of patients with relapsing-remitting multiple sclerosis, suggesting that the rate of atrophy increases as the disease becomes more established.

Quantitative contrast-enhanced magnetic resonance imaging to evaluate blood-brain barrier integrity in multiple sclerosis: a preliminary study

Gadolinium enhanced magnetic resonance imaging detects focal blood-brain barrier breakdown in new inflammatory multiple sclerosis lesions, but such lesions do not correlate with disease progression. To explore whether the latter might relate to subtle but widespread blood-brain barrier (BBB) breakdown with low grade inflammation mediating tissue damage, quantitative techniques were used to detect subtle gadolinium enhancement within otherwise normal-appearing white matter and within lesions not showing visible enhancement. T1-weighted imaging was performed prior to and at 5, 20 and 40 min following injection of 0.3 mmol/kg gadopentate dimeglumine in 33 patients with multiple sclerosis and five healthy control subjects. In healthy controls, a significant increase in white matter signal 5 min following contrast injection was observed (1.8%, P < 0.0005); the signal returned to baseline values by 20 min. In multiple sclerosis patients, a non-significant trend was noted for signal to remain elevated in normal-appearing white matter at the 20 and 40 min post-contrast time points; this was most apparent in primary progressive multiple sclerosis. Significant increases in signal intensity were noted at all time points post contrast in apparent non-enhancing lesions. The transient post contrast signal increase in controls is likely due to intravascular gadopentate dimeglumine. The persistent increases in signal intensity in non-enhancing lesions suggest more widespread abnormalities in BBB than is visually apparent, but substantiation of BBB leakage in normal appearing white matter will require further study using more sensitive methods.

Magnetisation transfer ratio histogram analysis of primary progressive and other multiple sclerosis subgroups

INTRODUCTION

Global magnetisation transfer ration (MTR) histogram analysis in the brain offers a method for evaluating pathological change both as a result of lesions and microscopic changes in normal appearing tissues.

METHODS

39 controls and 83 MS patients (46 primary progressive, 11 benign, 10 relapsing-remitting, 16 secondary progressive) were studied to explore the relationship of six conventional MTR histogram parameters with MS clinical subgroups and disability. Principal component (PC) analysis, which makes use of all the histogram data, was also used to examine the relationship between the MTR histogram and disability.

RESULTS

When primary progressive patients were compared to controls, there were abnormalities of average MTR, and MTR at the 25th, 50th and 75th percentile. Disabled relapsing onset patients exhibited abnormalities in the same four parameters. Benign and nondisabled relapsing onset patients exhibited no significant abnormalities. Modest correlations were observed between disability and individual MTR parameters in relapse onset but not primary progressive patients--PC analysis revealed stronger and significant associations with disability in both subgroups. (r=0.40 for primary progressive and r=0.51 for relapsing onset).

CONCLUSION

A number of MTR parameters are abnormal in primary progressive MS. MTR abnormalities are seen in disabled patients, whether of relapsing or primary progressive onset. The improved correlation with disability obtained by PC analysis suggests a useful role of this method for following clinically relevant pathological changes depicted in the MTR histogram.

Assessing the risk of early multiple sclerosis in patients with clinically isolated syndromes: the role of a follow up MRI

OBJECTIVES

With increasing evidence that permanent tissue damage occurs early in the course of multiple sclerosis, it is important that treatment trials include patients in the earliest stages of the disease. For many patients with multiple sclerosis the first presentation is a clinically isolated syndrome. Not all patients with a clinically isolated syndrome develop multiple sclerosis, however, and treatment of all such patients would be unwarranted. A single abnormal brain MRI identifies patients at a higher risk for the early development of multiple sclerosis, but current criteria are limited by either poor specificity (T2 lesions) or sensitivity (contrast enhancing lesions). The aim of the study was to assess the positive predictive value, sensitivity, and specificity of MRI indices for the development of multiple sclerosis after 1 year from two MRI examinations obtained 3 months apart.

METHODS

MRI examinations were performed in 68 patients with a clinically isolated syndrome, with a clinical assessment after 1 year.

RESULTS

Contrast enhancing lesions at both time points were the most predictive indices for developing multiple sclerosis (positive predictive value 70%) but had low sensitivity (39%). The combination of T2 lesions at baseline with new T2 lesions at follow up had the best overall positive predictive value (53%), sensitivity (83%), and specificity (76%). In patients with T2 lesions at baseline, the presence or absence of new T2 lesions at follow up significantly altered the risk of multiple sclerosis within 1 year (55% and 5% respectively, p<0.001). Multiple sclerosis also developed in 10% of patients with a normal baseline MRI.

CONCLUSIONS

Serial imaging in patients with clinically isolated syndromes improved the positive predictive value, sensitivity, and specificity of MRI for the development of early multiple sclerosis and also identified patients at a lower risk of early multiple sclerosis than would have been expected from their abnormal baseline MRI. Selection of patients with clinically isolated syndromes for therapeutic intervention or clinical trials may benefit from serial MRI, to target those at greatest risk of early development of multiple sclerosis.

Preliminary evidence for neuronal damage in cortical grey matter and normal appearing white matter in short duration relapsing-remitting multiple sclerosis: a quantitative MR spectroscopic imaging study

Neuronal damage and loss is likely to underlie irreversible disability in multiple sclerosis (MS). The time of onset, location and extent of neuronal damage in early disease are all uncertain. To explore this issue 16 patients with short duration, mild relapsing-remitting disease (mean disease duration 1.8 years, median EDSS 1) were studied using short echo time proton magnetic resonance spectroscopic imaging (1H-MRSI) to quantify the concentration of the neuronal marker N-acetyl-aspartate (NAA). The data were compared with those from 12 age-matched controls. 1H-MRSI was obtained from a 1.5-cm-thick slice just above the lateral ventricles. The Linear Combination (LC) Model combined with locally developed software allowed automated measurement of absolute metabolite concentrations from lesions, normal-appearing white matter (NAWM) and cortical grey matter (CGM). MS CGM exhibited significantly lower NAA (P = 0.01) and myo-inositol (P = 0.04) than control CGM. MS NAWM exhibited a lower concentration of NAA (P = 0.01) and increased myo-inositol (P = 0.03) than control white matter. More marked reductions in NAA and increases in myo-inositol were seen in lesions. The reduced NAA in MS CGM and NAWM suggest that mild but widespread neuronal dysfunction or loss occurs early in the course of relapsing-remitting MS. This preliminary finding should be confirmed in a larger cohort, and follow-up studies are also needed to determine the prognostic and pathophysiological significance of these early changes.

The predictive value of gadolinium enhancement for long term disability in relapsing-remitting multiple sclerosis--preliminary results

As short-term MRI studies are increasingly being used to monitor disease activity in multiple sclerosis (MS) it is vital to establish if short-term MRI activity is predictive of long term clinical outcome. We followed up after 5 years a group of 10 benign (relapsing-remitting MS with a disease duration > 10 years and EDSS < or = 3) and 10 early relapsing-remitting patients who previously had monthly serial MRI scans for 6 months. In the early relapsing-remitting group median EDSS at entry to the initial serial study was three and in the benign group 2.5. At 5-year follow up, five of these 20 patients had developed a definite deterioration in EDSS. The median number of new enhancing lesions detected originally in the group that had deteriorated was 11 (7-17) compared to 0 (0-5) new enhancing lesions, for those who had not deteriorated (P < 0.05). There was a trend towards a higher baseline T2 lesion load in the group with a definite change in EDSS but this was not significant This study suggests that short-term measurement of the number of gadolinium enhancing lesions may predict long term outcome in relapsing-remitting MS.

The Val-210-Ile pathogenic Creutzfeldt-Jakob disease mutation increases both the helical and aggregation propensities of a sequence corresponding to helix-3 of PrP(C)

A peptide corresponding to the third helical region within the PrP(C) protein, from residues 198 to 218 (helix-3), was synthesised with and without the familial 210-Val to Ile Creutzfeldt-Jakob disease mutation. The NMR structure of PrP(C) predicts no global variation in stability for this mutation, indicating that local sequence rather than global structural factors are involved in the pathological effects of this mutation. 1H NMR analysis of peptides with and without this mutation indicated that it had no significant effect on local helical structure. Temperature denaturation studies monitored by CD showed that the mutation increased the helical content within this region (helical propensity), but did not stabilise the helix toward denaturation (helical stability). Aggregation data indicated that, in addition to increasing helical propensity, this mutation increased the aggregation propensity of this sequence. CD and NMR data indicate that helical interactions, stabilised by the Val-210-Ile mutation, may precede the formation of beta-sheet aggregates in this peptide sequence. Therefore, this pathological mutation probably does not facilitate PrP(C) to PrP(Sc) conversion by directly destabilising the helical structure of PrP(C), but may preferentially stabilise PrP(Sc) by facilitating beta-sheet formation within this sequence region of PrP. In addition, helical interactions between helix-3 in two or more PrP(C) molecules may promote conversion to PrP(Sc).

T1 lesion load and cerebral atrophy as a marker for clinical progression in patients with multiple sclerosis. A prospective 18 months follow-up study

We investigated the relationship between local tissue destruction, diffuse cerebral atrophy and clinical progression in patients with established multiple sclerosis (MS). Twenty-nine patients with MS (13 patients with relapsing--remitting and 16 with secondary progressive disease) were included in a prospective serial study. Cerebral volumes, T1 hypointense lesion volumes, T2 hyperintense lesion volumes at baseline and at 18 months follow-up, and the volume of monthly enhancing lesions from month 0 to month 9 were assessed on magnetic resonance imaging (MRI) brain scans using highly reproducible semi-automated quantitative techniques. The main outcome measures were the MRI parameters and disability on Kurtzkes' Expanded Disability Status Scale. There was a significant correlation between the change (increase) in T1 lesion volume and progressive cerebral atrophy, whereas no correlation between the T2 lesion volume and atrophy was seen over the same follow-up period. The change in T1 lesion volume correlated more strongly than did T2 lesion volume change with the change in disability. We conclude that hypointense abnormalities detected in T1-weighted brain scans and cerebral atrophy may be directly linked. Although one should bear in mind some potential for reversibility due to inflammatory, oedematous lesions, these MR measures are a useful marker of progressive tissue damage and clinical progression in established MS.

Community services in multiple sclerosis: still a matter of chance

OBJECTIVES

People with multiple sclerosis often have multiple complex needs that require input from a wide range of services. Many complain that services are inadequate and poorly coordinated. Few studies have been undertaken to support this contention and objective data are scarce. The level of services and home modifications received by people with multiple sclerosis across a broad range of disease severity has been investigated.

METHODS

As part of a quality of life study, 150 adults with clinically definite multiple sclerosis were interviewed, using a structured questionnaire, to determine their current use of outpatient and community services and the home modifications in place. Disability, handicap, and emotional status were also measured.

RESULTS

Forty five per cent of people did not receive any community services other than contact with their general practitioner. Thirty nine per cent of people with moderate and 12% with severe disability failed to receive community services. For the services received: 17% had contact with a community nurse; 33% with a care attendant or home help; 23% with a physiotherapist, 21% with an occupational therapist, and 10% with a social worker. Fifty eight per cent of people had modifications to their home as a direct result of multiple sclerosis. The relation between level of disability and number of services and adaptations received was moderate (r=0.58 and 0.54 respectively) and the relation between level of services and age (r=0.12), living alone (r=0.16), and emotional status (r=0.10) was negligible.

CONCLUSIONS

Despite a shift of emphasis from hospital to community care, and the establishment of standards of care for multiple sclerosis, many people with moderate or severe disability fail to receive assistance. These results provide evidence to support the dissatisfaction felt by people with multiple sclerosis in relation to the services they receive. It raises questions about equitable allocation of resources and highlights the urgent need for a review of community services.

The effect of interferon beta-1b treatment on MRI measures of cerebral atrophy in secondary progressive multiple sclerosis. European Study Group on Interferon beta-1b in secondary progressive multiple sclerosis

The recently completed European trial of interferon beta-1b (IFNbeta-1b) in patients with secondary progressive multiple sclerosis (SP multiple sclerosis) has given an opportunity to assess the impact of treatment on cerebral atrophy using serial MRI. Unenhanced T(1)-weighted brain imaging was acquired in a subgroup of 95 patients from five of the European centres; imaging was performed at 6-month intervals from month 0 to month 36. A blinded observer measured cerebral volume on four contiguous 5 mm cerebral hemisphere slices at each time point, using an algorithm with a high level of reproducibility and automation. There was a significant and progressive reduction in cerebral volume in both placebo and treated groups, with a mean reduction of 3.9 and 2.9%, respectively, by month 36 (P = 0.34 between groups). Exploratory subgroup analyses indicated that patients without gadolinium (Gd) enhancement at the baseline had a greater reduction of cerebral volume in the placebo group (mean reduction at month 36: placebo 5.1%, IFNbeta-1b 1.8%, P < 0.05) whereas those with Gd-enhancing lesions showed a trend to greater reduction of cerebral volume if the patient was on IFNbeta-1b (placebo 2.6%, IFNbeta-1b 3.7%; P > 0.05). These results are consistent with ongoing tissue loss in both arms of this study of secondary progressive multiple sclerosis. This finding is concordant with previous observations that disease progression, although delayed, is not halted by IFNbeta. The different pattern seen in patients with and without baseline gadolinium enhancement suggests that part of the cerebral volume reduction observed in IFNbeta-treated patients may be due to the anti-inflammatory/antioedematous effect of the drug. Longer periods of observation and larger groups of patients may be needed to detect the effects of treatment on cerebral atrophy in this population of patients with advanced disease.

Congenital lobar emphysema occurring in twins

Twins born with congenital lobar emphysema are reported. This has not previously been described. Diagnosis, surgical management and subsequent course is high-lighted. These twins may well be the smallest to have operative treatment.

MTR and T1 provide complementary information in MS NAWM, but not in lesions

MTR and T1 relaxation times are abnormal in MS lesions and NAWM, and may reflect tissue damage such as demyelination and axonal loss. Their relationship and potential to provide complementary information in tissue characterisation is explored. The aim of this study was to document the relationship between magnetisation transfer ratio (MTR) and T1 relaxation time in Multiple Sclerosis (MS) lesions and normal appearing white matter (NAWM) in order to determine whether the combination provides a more comprehensive tissue characterisation than either parameter in isolation. Ten patients with relapsing remitting MS and 10 age matched healthy controls underwent imaging using a protocol which included the measurement of both MTR and T1 relaxation times. The MTR and T1 values were compared statistically using a commonly adopted correlation approach and a mixed-model regression approach. There was a strong correlation between MTR and T1 in MS lesions (r=0.74). The correlation was seen equally in T1 hypointense and isointense lesions. The relationship was much weaker in MS NAWM (r=0.24) and no correlation was found in control white matter (r=0.06). Mixed-model regression analysis confirmed that the relationship between T1 and MTR is strongly dependent upon tissue type (MS lesion, MS NAWM, or control white matter). The relationship between MTR and T1 relaxation time measurements varies markedly between pathological and normal tissue types. In MS, the complementary information obtained from MTR and T1 is most apparent in NAWM. The results emphasise the potential for combinations of MR parameters to improve tissue characterisation, which in turn should improve understanding of disease pathology and treatment monitoring. Multiple Sclerosis (2000) 6 327 - 331

Functional differences between splice variants of the murine 5-HT(3A) receptor: possible role for phosphorylation

The murine 5-HT(3A) receptor subunit is expressed as either of two splice variants which are differentially regulated in vivo. The difference resides in a six-amino acid sequence within the cytoplasmic loop between transmembrane regions 3 and 4, which is present in the long form but not the short form. No physiological roles have yet been ascribed to the two splice variants. Whole cell patch clamp recording from transfected HEK 293 cells stably expressing either long or short form receptors showed very similar responses under control conditions. However, inclusion of 1 mM cAMP (activator of protein kinase A) in the patch pipette caused an initial increase in the desensitization rate of the long form, but a decrease in the short form. With the addition of 100 nM phorbol 12-myristate 13-acetate (PMA; activator of protein kinase C) to the pipette solution, responses elicited with 1 microM 5-HT revealed an increase in the current amplitude in the long but not the short form of the receptor. Over a longer time period, inclusion of PMA in the patch-pipette caused a faster run down of peak current amplitude in response to 30 microM 5-HT in the long form but did not affect the short form; there was no observed long-term effects of cAMP. We conclude that the long and short forms of the 5-HT(3) receptor are differentially modulated by agents that activate PKA and PKC. These different patterns of modulation could have markedly divergent consequences on receptor function.

Variations in T1 and T2 relaxation times of normal appearing white matter and lesions in multiple sclerosis

OBJECTIVE

To investigate the variation in T1 and T2 relaxation times of normal appearing white matter (NAWM) and lesions in multiple sclerosis (MS) throughout the brain.

BACKGROUND

The magnetic resonance imaging (MRI) sequence fast FLAIR (fluid attenuated inversion recovery) has demonstrated overall increased lesion detection when compared to conventional or fast spin echo (FSE) but fewer lesions in the posterior fossa and spinal cord. The reasons for this are unknown, but may be due to variations in the T1 and T2 relaxation times within NAWM and MS lesions.

METHOD

Ten patients and 10 controls underwent MRI of the brain which involved FSE, fast FLAIR and the measurement of T1 and T2 relaxation times.

RESULTS

Of 151 lesions analysed (22 infra-tentorial, 129 supra-tentorial), eight were missed by the fast FLAIR sequence. T1 and T2 relaxation times in normal controls were longer in the infra-tentorial, than supra-tentorial, region. Patient NAWM relaxation times were prolonged compared with control values in both regions. Lesions demonstrated longer relaxation times than either control white matter or patient NAWM in both regions, however this difference was less marked infra-tentorially. The eight posterior fossa lesions not visible on the fast FLAIR sequence were characterised by short T1 and T2 relaxation times which overlapped with the patient NAWM for both T1 and T2 and with control values for T2 relaxation times.

CONCLUSION

Both lesion and NAWM relaxation time characteristics vary throughout the brain. The T1 and T2 relaxation times of infra-tentorial lesions are closer to the relaxation times of local NAWM than supra-tentorial lesions, resulting in reduced contrast between posterior fossa lesions and the background NAWM. Consequently the characteristics of some lesions overlap with those of NAWM resulting in reduced conspicuity. By utilising this information, it may be possible to optimise fast FLAIR sequences to improve infra-tentorial lesion detection.

Relationship between feeding practices and weanling diarrhoea in northeast Thailand

Diarrhoea is a major public health problem in Thailand. During November 1998-January 1999, a cross-sectional survey and a nested qualitative study were conducted to understand the relationship between feeding practices and weanling diarrhoea, and to describe the related local beliefs and practices in a subdistrict of northeast Thailand. A cluster-sampling method was used for selecting 156 weanlings aged 3-24 months. A structured interview was conducted with the main caregivers of these weanlings. The questionnaire used for the interview included items about feeding practices and diarrhoea-history of the weanlings in 2 months prior to the interview. Seven focus-group discussions with an opportunistic sample of the caregivers were held in the villages. A series of vignettes and unstructured questions were used for eliciting the local beliefs about weanling diarrhoea and its causes. Thirty-six (23%) of the 156 weanlings had diarrhoea in 2 months prior to the interview. The factors that were significantly related to reported weanling diarrhoea included consumption of unboiled water by weanlings (OR = 10, p = 0.03), not covering perishable foods (OR = 3, p = 0.02), and washing feeding utensils of weanlings without dishwashing detergent (OR = 3.1, p = 0.02), 'Su' and 'tongsia'--two common local terms--were used for describing different types of weanling diarrhoea. Many caregivers considered 'su' a natural occurrence in a child's development. The results suggest that some poor feeding practices may contribute to the higher risk of weanling diarrhoea in northeast Thailand. Some local beliefs about weanling diarrhoea may mask the true causes, and mislead messages about its prevention.