Paraclinical tests in acute-onset optic neuritis: basal data and results of a short follow-up

The clinical course of multiple sclerosis

Knowledge of the epidemiology and natural history of multiple sclerosis (MS) is essential for practitioners and patients to make informed decisions about their care. This knowledge, in turn, depends upon the findings from reliable studies (i.e., those which adhere to the highest methodological standards). For a clinically variable disease such as MS, these standards include case ascertainment using a population-based design; a large-sized sample of patients, who are followed for a long time-period in order to provide adequate statistical power; a regular assessment of patients that is prospective, frequent, and standardized; and the application of rigorous statistical techniques, taking into account confounding factors such as the use of disease modifying therapy or the age at clinical onset. In this chapter we review the available epidemiologic and natural history data as it relates clinical issues such as the likelihood of incomplete recovery from a first attack; the likelihood and time course of a second attack; the likelihood and time course of disease progression and the accumulation of irreversible disability; the disease prognosis based both upon the clinical nature and presentation of the first episode and upon the initial disease course; and the impact of disease on mortality. In addition, these studies provide insight to the pathophysiologic mechanisms underlying the course and prognosis of MS. Studies of the Lyon cohort have been particularly helpful in this regard and observations from this cohort have led to the hypothesis that, in large part, the accumulation of disability in MS is an age-related process, which is independent of the clinical subtype of MS (i.e., relapsing-remitting, primary progressive, secondary progressive, or relapsing progressive). And finally, we consider briefly the impact of various life events (e.g., pregnancy, infection, vaccination, trauma, and stress) on the clinical course of disease.

Clinical and radiological characteristics of tumefactive demyelinating lesions: follow-up study

BACKGROUND

Demyelinating lesions over 20 mm in size, referred to as tumefactive demyelinating lesions, can be misdiagnosed as being either a tumor or an abscess. Although some radiological characteristics can help make a differential diagnosis easier, a cerebral biopsy may still be necessary.

OBJECTIVE

Our objective was to assess the clinical characteristics of tumefactive lesions, with or without a diagnosis of multiple sclerosis (MS), and present follow-up data for 54 patients with tumefactive lesions.

METHODS

Demographic, clinical, radiological and laboratory data were gathered and treatment responses were evaluated in a total of 54 patients from five medical centers.

RESULT

Twenty-nine patients were diagnosed with tumefactive lesions at the onset, whereas 25 patients were diagnosed with tumefactive lesions after a diagnosis of MS. Median follow-up was 38.12 months. At final examination, 19 of the patients with a tumefactive lesion diagnosis at the onset eventually developed relapsing-remitting MS, while 10 remained with the condition as a clinically isolated syndrome. The tumefactive lesions studied were mostly focal, with closed-ring enhancement. We found that oligoclonal band positivity was less frequent in the patients with tumefactive onset.

CONCLUSION

Although our demographic data were similar to formerly collected Turkish MS data, we found that the distribution of the patients' clinical course differed if there was an absence of primary progressive MS and that there was a lower frequency of secondary progressive MS cases in our group of patients. We believe that less frequent oligoclonal band positivity and the difference we witnessed in the clinical course of disease in our study groups suggest that there is a need for further studies to compare all the biological and immunological differences between MS and tumefactive lesion cases, in order to reveal whether there are different pathogenetic mechanisms involved.

Oligoclonal bands predict multiple sclerosis after optic neuritis: a literature survey

BACKGROUND

Multiple sclerosis (MS) is an autoimmune disease resulting in inflammation and demyelination of neurones in the central nervous system (CNS). The first sign of MS is often monosymptomatic optic neuritis (MON). Cerebrospinal fluid from a patient with MS analysed by electrophoresis often shows a split to form so called oligoclonal bands (OCBs). OCBs consist of proteins from activated lymphocytes and plasma cell clones.

OBJECTIVES

The aim of this study was to review the published literature on OCBs in MON patients and perform a meta-analysis of the studies in order to assess the utility of OCB determination in patients with MON in the prediction of their risk of MS.

METHODS

Review and meta-analysis of the results of 10 published studies.

RESULTS

OCBs as a predictive test had a sensitivity of 73-100% (mean 88.5%), a specificity of 41-90% (mean 57%) and OR-values between 2.75 and 171 (mean 34.2). The areal under the summary receiver operator characteristic (ROC) curve was 0.89 (unweighted) and 0.82 (weighted). The studies showed large heterogeneity in the diagnostic accuracy.

CONCLUSION

This literature-based meta-analysis provides evidence that OCBs may have a high predictive value for the development of MS in patients with MON. Standardization of laboratory methods and diagnostic criteria would help bring out the full clinical potential of the test. To elucidate the predictive value of OCBs versus MRI, we recommend that a similar meta-analysis of studies of MRI in MON be performed.

Current and future disease-modifying therapies in multiple sclerosis

The development of disease-modifying therapies (DMT) in multiple sclerosis (MS) has rapidly evolved over the last few years and continues to do so. Prior to the United States Food and Drug Administration approval of the immunomodulatory agent, interferon-beta1b in 1993, no other drug had been shown to alter the course of the disease in a controlled study of MS. At present, there are five licenced disease-modifying agents in MS - interferon-beta1b, interferon-beta1a, glatiramer acetate, natalizumab and mitoxantrone. All have shown significant therapeutic efficacy in large controlled trials. However, current therapies are only partially effective and are not free from adverse effects. Moreover, available DMTs are overwhelmingly biased in favour of those with relapsing-remitting disease. Effective treatment for progressive MS is severely limited, with only interferon-beta1b and mitoxantrone having licenced use in secondary progressive, but not primary progressive disease. Monoclonal antibodies, such as natalizumab selectively target immune pathways involved in the pathogenic process of MS. Alemtuzumab, daclizumab and rituximab are other notable monoclonal antibodies currently undergoing phase II and III trials in MS. Alemtuzumab has so far shown promising therapeutic benefit in relapsing disease, although immunological adverse effects have been a problem. Oral therapies have the benefit of improved tolerability and patient compliance compared with current parenteral treatments. Cladribine and fingolimod (FTY720) have shown encouraging results in their phase III clinical trials. It is also worth noting the evidence for starting DMT in patients with clinically isolated syndrome, whereby early treatment has shown to delay the onset of clinically definite MS in separate phase III studies.

Cerebrospinal fluid biomarkers in multiple sclerosis

In patients with multiple sclerosis (MS) intensive efforts are directed at identifying biomarkers in bodily fluids related to underlying disease mechanisms, disease activity and progression, and therapeutic response. Besides MR imaging parameters cerebrospinal fluid (CSF) biomarkers provide important and specific information since changes in the CSF composition may reflect disease mechanisms inherent to MS. The different cellular and protein-analytical methods of the CSF and the recommended standard of the diagnostic CSF profile in MS are described. A brief update on possible CSF biomarkers that might reflect key pathological processes of MS such as inflammation, demyelination, neuroaxonal loss, gliosis and regeneration is provided.

The clinical epidemiology of multiple sclerosis

A comprehensive knowledge of the natural course and prognosis of multiple sclerosis is of utmost importance for a physician to make it affordable in simple descriptive terms to a patient when personal and medical decisions are to be taken. It is still topical because the currently acknowledged disease-modifying agents only marginally alter the overall prognosis of the disease. It provides reference for evaluating the efficacy of a therapeutic intervention in clinical trials; clues for public health services, health insurance companies, and pharmaceutical industry in their respective activities; and insights into the pathophysiology and the treatment of multiple sclerosis. Precise, consistent, and reliable data from appropriate cohorts have become available and knowledge is fairly comprehensive.

Multiple sclerosis

Multiple sclerosis is the most common disabling neurologic disease affecting young adults and adolescents in the United States. The first objective of this article is to familiarize nonspecialists with the cardinal features of multiple sclerosis and our current understanding of its etiology, epidemiology, and natural history. The second objective is to explain the approach to diagnosis. The third is to clarify current evidence-based treatment strategies and their roles in disease modification. The overall goal is to facilitate the timely evaluation and confirmation of diagnosis and enhance effective management through collaboration among primary physicians, neurologists, and other care providers who are confronted with these formidably challenging patients.

Clinical and radiographic spectrum of pathologically confirmed tumefactive multiple sclerosis

Atypical imaging features of multiple sclerosis lesions include size >2 cm, mass effect, oedema and/or ring enhancement. This constellation is often referred to as ‘tumefactive multiple sclerosis’. Previous series emphasize their unifocal and clinically isolated nature, however, evolution of these lesions is not well defined. Biopsy may be required for diagnosis. We describe clinical and radiographic features in 168 patients with biopsy confirmed CNS inflammatory demyelinating disease (IDD). Lesions were analysed on pre- and post-biopsy magnetic resonance imaging (MRI) for location, size, mass effect/oedema, enhancement, multifocality and fulfilment of Barkhof criteria. Clinical data were correlated to MRI. Female to male ratio was 1.2 : 1, median age at onset, 37 years, duration between symptom onset and biopsy, 7.1 weeks and total disease duration, 3.9 years. Clinical course prior to biopsy was a first neurological event in 61%, relapsing–remitting in 29% and progressive in 4%. Presentations were typically polysymptomatic, with motor, cognitive and sensory symptoms predominating. Aphasia, agnosia, seizures and visual field defects were observed. At follow-up, 70% developed definite multiple sclerosis, and 14% had an isolated demyelinating syndrome. Median time to second attack was 4.8 years, and median EDSS at follow-up was 3.0. Multiple lesions were present in 70% on pre-biopsy MRI, and in 83% by last MRI, with Barkhof criteria fulfilled in 46% prior to biopsy and 55% by follow-up. Only 17% of cases remained unifocal. Median largest lesion size on T2-weighted images was 4 cm (range 0.5–12), with a discernible size of 2.1 cm (range 0.5–7.5). Biopsied lesions demonstrated mass effect in 45% and oedema in 77%. A strong association was found between lesion size, and presence of mass effect and/or oedema (P< 0.001). Ring enhancement was frequent. Most tumefactive features did not correlate with gender, course or diagnosis. Although lesion size >5 cm was associated with a slightly higher EDSS at last follow-up, long-term prognosis in patients with disease duration >10 years was better (EDSS 1.5) compared with a population-based multiple sclerosis cohort matched for disease duration (EDSS 3.5; P< 0.001). Given the retrospective nature of the study, the precise reason for biopsy could not always be determined. This study underscores the diagnostically challenging nature of CNS IDDs that present with atypical clinical or radiographic features. Most have multifocal disease at onset, and develop RRMS by follow-up. Although increased awareness of this broad spectrum may obviate need for biopsy in many circumstances, an important role for diagnostic brain biopsy may be required in some cases.

Multiple sclerosis

Multiple sclerosis (MS) is the most common disabling neurologic disease of young people affecting between 350 and 450,000 individuals in the United States. Substantial advances have been made in the diagnostic assessment and treatment interventions over the last 10 years such that we are now able effectively to treat both the disease process and the associated symptomatic complaints associated with MS. Most patients consult with their primary care physician at the time when the first clinical manifestations of MS emerge. These physicians play a central role in the early identification and treatment of patients with MS. This article emphasizes the expanding diagnostic and therapeutic capabilities evolving for the MS patient and the crucial role played by primary care physicians in collaboration with neurologists in the coordination of the initial diagnostic and treatment plan.

A new measure of dysconjugacy in INO: the first-pass amplitude

BACKGROUND

The ratios of abducting to adducting eye movements (versional dysconjugacy index, VDI) for saccadic velocity and acceleration have been useful measures by which to objectively characterize internuclear ophthalmoparesis (INO). Amplitude measures of dysconjugacy have been less useful, given that many patients maintain the ability to ultimately reach a centrifugal fixation target and that traditional amplitude measures of VDI have focused on this 'final amplitude' (FA) position.

METHODS

We utilized infrared oculography to define a new amplitude measure of dysconjugacy in 42 multiple sclerosis (MS) patients with INO. The first-pass amplitude (FPA)-VDI is the ratio of abduction/adduction eye movement amplitudes computed at the time when the abducting eye initially achieves the centrifugal horizontal fixation target.

RESULTS

FPA-VDI values were significantly more sensitive and specific than FA-VDI values in demonstrating dysconjugacy in INO, and there was a 14-fold increase in dysconjugacy as measured by FPA-VDI Z-scores when compared to FA-VDI Z-scores.

CONCLUSION

Consideration of velocity (pulse) and amplitude (step) components of dysconjugacy in patients with INO can provide a greater understanding of the dynamic aspects of this syndrome. We propose to characterize the relationship between the pathophysiology of INO and neuroradiologic measures of tissue injury in MS.

Isolated demyelinating syndromes: comparison of CSF oligoclonal bands and different MR imaging criteria to predict conversion to CDMS

AIM OF THE STUDY

To evaluate and compare the capacity of oligoclonal bands (OB) and three sets of MR imaging criteria to predict the conversion of clinically isolated syndromes (CIS) to clinically definite multiple sclerosis (CDMS).

PATIENTS AND METHODS

One hundred and twelve patients with CIS were prospectively studied with MR imaging and determination of OB. Based on the clinical follow-up (conversion or not conversion to CDMS), we calculated the sensitivity, specificity accuracy, positive and negative predictive value of the OB, and MR imaging criteria proposed by Paty et al, Fazekas et al and Barkhof et al.

RESULTS

CDMS developed in 26 (23.2%) patients after a mean follow-up of 31 months (range 12-62). OB were positive in 70 (62.5%) patients and were associated with a higher risk of developing CDMS. OB showed a sensitivity of 81%, specificity of 43%, accuracy of 52%, positive predictive value (PPV) of 30% and negative predictive value (NPV) of 88%. Paty and Fazekas criteria showed the same results with a sensitivity of 77%, specificity of 51%, accuracy of 57%, positive predictive value of 32% and negative predictive value of 88%. Barkhof criteria showed a sensitivity of 65%, specificity of 70%, accuracy of 69%, PPV of 40% and NPV of 87%. The greatest accuracy was achieved when patients with positive OB and three or four Barkhof's criteria were selected.

CONCLUSIONS

We observed a high prevalence of OB in CIS. OB and MR imaging (Paty's and Fazekas' criteria) have high sensitivity. Barkhof's criteria have a higher specificity. Both OB and MR imaging criteria have a high negative predictive value.

Effect of early interferon treatment on conversion to definite multiple sclerosis: a randomised study

BACKGROUND

Interferon beta reduces activity in multiple sclerosis as measured clinically and by magnetic resonance imaging (MRI). We assessed the effect of interferon beta-1a on the occurrence of relapses in patients after first presentation with neurological events, who are at high risk of conversion to clinically definite multiple sclerosis.

METHODS

Eligible patients had had a first episode of neurological dysfunction suggesting multiple sclerosis within the previous 3 months and had strongly suggestive brain MRI findings. Patients were randomly assigned interferon beta-1a 22 microg or placebo subcutaneously once weekly for 2 years. Neurological and clinical assessments were done every 6 months and brain MRI every 12 months. Analyses excluded one patient assigned placebo who received no study injections.

FINDINGS

241 (78%) of 308 randomised patients received study treatment for 2 years; 278 (90%) remained in the study until termination. 57 (85%) of 67 who stopped therapy did so after conversion to clinically definite multiple sclerosis. Fewer patients developed clinically definite multiple sclerosis in the interferon group than in the placebo group (52/154 [34%] vs 69/154 [45%]; p=0.047). The time at which 30% of patients had converted to clinically definite multiple sclerosis was 569 days in the interferon group and 252 in the placebo group (p=0.034). The annual relapse rates were 0.33 and 0.43 (p=0.045). The number of new T2-weighted MRI lesions and the increase in lesion burden were significantly lower with active treatment.

INTERPRETATION

Interferon beta-1a treatment at an early stage of multiple sclerosis had significant positive effects on clinical and MRI outcomes.

Ophthalmology update for primary practitioners. Part I. Update on optic neuritis

Optic neuritis is a common cause of acute visual loss. It is typified by sudden onset of visual impairment and pain with eye movements, followed by spontaneous recovery of vision over several months. Pathologically, optic neuritis is an acute demyelinating event affecting the optic nerve. Objective physical findings are typically few, including an afferent pupillary defect or Marcus-Gunn pupil, whereas subjective psychophysical findings abound (ie, diminished central visual acuity, color vision, decreased contrast sensitivity, and visual field abnormalities). These characteristics have made the diagnosis of optic neuritis based solely on clinical grounds disquieting to practitioner and patient alike. In addition, the fact that optic neuritis is often associated with multiple sclerosis as the first clinical manifestation of disease gives further reason for both patient and physician anxiety. The serious nature of visual loss and the consequences of making the diagnosis of optic neuritis has given rise to extensive testing and expensive treatments. This review is intended to explore our current state of knowledge with regard to (1) clinical presentation, (2) ancillary testing, (3) therapeutic intervention, and (4) associated disease, specifically the risk for multiple sclerosis in the patient who presents with an acute optic neuritis. Finally, a suggestion guide for informing the patient and addressing his or her concerns will be presented.

Progression of optic neuritis to multiple sclerosis: an 8-year follow-up study

OBJECTIVE

The relationship between acute monosymptomatic optic neuritis (AON) and subsequent multiple sclerosis (MS) is still doubtful. We investigated the risk of developing MS in patients from North Bavaria, who were suffering from AON.

PATIENTS/METHODS

Twenty-nine patients with clinical evidence of AON were included in the study. Initial evaluation included brain resonance imaging (MRI) and a clinical neurological examination. Follow-up examinations were performed after 72-108 months (mean: 96 months) in 26 patients (three patients were lost to follow-up) and consisted of a second complete neurological examination. Diagnosis of MS was established according to the criteria of Poser CM, Paty DW, Scheinberg L. New diagnostic criteria for multiple sclerosis: guidelines for research protocols. Ann Neurol 1983:13:227-231.

RESULTS

At follow-up, 14 of 26 patients (54%) had converted to clinically definite MS. Nine patients (64%) had developed MS within 2 years after the onset of AON.

CONCLUSION

We observed the development of MS in 54% of the 26 investigated AON patients. The exceptional feature of the present study was the relatively long follow-up period of 8 years.

Long term MRI follow-up of patients with post infectious encephalomyelitis: evidence for a monophasic disease

Post infectious encephalomyelitis and multiple sclerosis are both inflammatory demyelinating disorders of the central nervous system. Whereas multiple sclerosis is a multi phasic disease with recurrent episodes disseminated in time and place, post infectious encephalomyelitis is usually considered to be a monophasic illness. This study used serial brain MRI to clarify whether the latter hypothesis holds for the long term. Post infectious encephalomyelitis was defined as the development of a central nervous system white matter disorder occurring in close temporal relationship with a viral, bacterial or other infection. There were eleven patients, mean age at presentation 21 years (4-48), and mean period of follow-up of 8 years (3.5-11). T2-weighted brain MRI was abnormal in all 11 cases during the acute stages of the illness. On follow-up 6 patients had made a complete clinical recovery, 4 patients had mild residual deficits and one severe neurological deficits necessitating ventilatory support. No patient experienced an exacerbation during the follow-up period. MRI revealed complete resolution of abnormalities in 3 and partial resolution in 7; new white matter lesions were seen in only one patient. This long term follow-up study suggests that there is a definable group with post infectious encephalomyelitis who exhibit a monophasic clinical and MRI pattern in the long term.

Asymptomatic spinal cord lesions in clinically isolated optic nerve, brain stem, and spinal cord syndromes suggestive of demyelination

OBJECTIVES

Conventional T2 weighted MRI studies have highlighted the fact that the presence of clinically silent brain lesions increases the risk of developing clinically definite multiple sclerosis after an isolated syndrome of the optic nerve, brain stem, or spinal cord. The objectives of the present study are: (1) to show whether or not these patients also have asymptomatic abnormalities of the spinal cord, and (2) to recruit a new cohort of such patients using high resolution MRI of both brain and spinal cord.

METHODS

The brain was imaged in the axial plane with 3 mm thick contiguous slices using a proton density and T2 weighted fast spin echo (FSE) sequence; a T1 weighted sequence after the injection of gadolinium-DTPA; and a fast fluid attenuated inversion recovery (fFLAIR) sequence. The spinal cord was imaged in the sagittal plane with 3 mm thick slices using a T2 weighted FSE and a T1 weighted gadolinium enhanced sequence.

RESULTS

Thirty three patients, mean age 31 (16-46) were recruited. There were 14 men and 19 women. Brain MRI was abnormal in 22 (67%); no patient was seen with abnormalities on only one or other sequence. Six patients (18%) displayed one or more gadolinium enhancing lesions on brain MRI. In the spinal cord, nine (27%) patients displayed one or more clinically silent lesions on FSE. Two patients showed one and two gadolinium enhancing lesions in the spinal cord respectively.

CONCLUSION

This high incidence of spinal cord lesions emphasises that asymptomatic demyelinating lesions may also involve clinically eloquent pathways. Follow up studies are required to determine their prognostic importance.

Cerebrospinal fluid myelin basic protein-like material in acute monosymptomatic optic neuritis

INTRODUCTION

Cerebrospinal fluid (CSF) may provide markers of severity and outcome of optic neuritis.

MATERIAL AND METHODS

We examined the CSF from 29 patients with acute monosymptomatic optic neuritis (AMON) for content of myelin basic protein-like material (MBPLM) and correlated the levels with results of cranial magnetic resonance imaging. The length of the time from onset of AMON to the time of CSF collection did not exceed four weeks.

RESULTS

Only two patients (7%), one of whom developed an acute myelopathy one month after AMON, showed an elevated value of CSF MBPLM. No MBPLM was detected in 6 patients (21%), and other 21 (72%) had detectable levels of MBPLM but below the upper limit of normal of 0.1 ng/ml. The value of MBPLM was not significantly correlated with the interval to CSF sampling from onset of AMON or with severity of decreased visual acuity. The highest values of CSF MBLPM were observed among patients with severely decreased visual acuity and among patients with an abnormal MRI (13 of 27 i.e. 48%).

CONCLUSIONS

CSF MBPLM was rarely abnormal in AMON. However, CSF MBPLM may have potential value in reflecting disease activity, as the highest values were obtained among patients with CSF sampled soon after the maximum visual dysfunction was reached, with severe visual impairment, and with an abnormal MRI.

Isolated optic neuritis and its prognosis for multiple sclerosis: a clinical and paraclinical study with evoked potentials. CSF examination and brain MRI

Our study evaluated the frequency of developing multiple sclerosis (MS) after acute isolated optic neuritis (ON), the possible association with risk factors (gender, age), and the diagnostic and prognosis role of paraclinical tests. We studied 100 ON patients (mean age 28.9 years: SD 8.9): 85 patients were regularly followed up. Sixty-six patients underwent multimodality evoked potential (EP) test, examination and brain MRI within six months of the onset of ON. Over a mean follow-up of 5.2 years, MS occurred in 28/85 cases. The risk of developing MS after four years was 0.35 at life-table analysis, regardless of gender or age at the onset of ON. Visual EPs in unaffected eyes were abnormal in 25.4%, brainstem auditory EPs in 6.5% somatosensory EPs in 8.1%, upper limb motor EPs in 6.8% of the tested patients; intrathecal IgG synthesis was revealed in 51.7% and MRI lesions in 73.8%. Fifty-one of the patients who underwent paraclinical tests were followed up for more than one year, and MS occurred in 13 cases. All of these presented MRI lesions, nine intrathecal IgG synthesis, and two abnormal extraocular EPs. The risk of developing MS after four years was 0.33 in patients with MRI lesions; the simultaneous presence of intrathecal IgG synthesis increased the risk to 0.46.

Guidelines for MRI monitoring of the treatment of multiple sclerosis: recommendations of the US Multiple Sclerosis Society's task force

In relapsing-remitting and secondary progressive multiple sclerosis (MS), MRI activity on monthly brain scans is a sensitive primary outcome measure in short term exploratory treatment trials. Because conventional MRI findings have a limited correlation with disability, the primary outcome in definitive trials should be clinical, although MRI is useful in providing an index of pathological progression. In trials aimed at preventing evolution from a clinically isolated syndrome to MS, MRI findings should be used in the entry criteria. The likely pathological substrates of irreversible disability are demyelination and axonal loss. Putative MR markers for these pathologies appear to relate more closely to disability than conventional MRI findings. Further technical developments should lead to improved quantitation, pathological specificity and clinical correlations.

Serial MRI, VEP, SEP and biotesiometry in acute optic neuritis: value of baseline results to predict the development of new lesions at one year follow up

INTRODUCTION

In an attempt to establish the value of MRI, VEP, SEP, and biotesiometry in monitoring disease evolution we undertook a one year follow up study of 70 untreated patients with acute optic neuritis (ON).

MATERIAL & METHODS

ON was monosymptomatic in 48 patients (bilateral in 10) and part of clinically definite multiple sclerosis (CDMS) in 22 patients, examined as mentioned below.

RESULTS

Results are given at onset and at follow up (in brackets). In monosymptomatic ON, brain MRI was abnormal in 53% (53%), VEP in the eye with acute ON in 79% (71%), VEP in the clinically unaffected eye in 34% (47%), SEP in 25% (23%), and biotesiometry in 29% (17%). In CDMS, brain MRI was abnormal in 95% (95%), VEP in the eye with acute ON in 86% (77%), VEP in the clinically unaffected eye in 50% (64%), SEP in 55% (50%), and biotesiometry in 63% (53%). Only minor changes in test scores were observed after one year except for significant improvement of VEP in eyes with acute ON. Eight of 32 patients, characterized by at least one abnormal paraclinical test at onset of monosymptomatic ON, had developed CDMS versus none of 16 patients with normal paraclinical results (p = 0.03; Fisher).

CONCLUSION

Patients with monosymptomatic ON with paraclinical signs of multifocal involvement at onset had an increased risk of developing CDMS. No single test predicted the evolution of CDMS, perhaps due to the relatively short follow up time.

Guidelines for the use of magnetic resonance techniques in monitoring the treatment of multiple sclerosis. US National MS Society Task Force

Because of the major difficulties in measuring clinical end points in multiple sclerosis (MS) treatment trials, there has been much enthusiasm for using magnetic resonance imaging (MRI) findings as an alternative outcome. To provide international consensus guidelines for the use of MRI in MS clinical trials, a task force of the US National MS Society was convened. The recommendations of the task force are presented in this review. Given the high sensitivity for detecting pathological activity in relapsing-remitting and secondary progressive MS, monthly T2-weighted and gadolinium-enhanced brain MRI is an excellent tool for short-term exploratory trials of new agents where it serves as the primary end point; in particular, failure to demonstrate a reduction in lesion activity avoids the time, cost, and risks of a larger clinical end point study. However, conventional MRI findings have a limited correlation with disability in established MS. The primary end point of a definitive trial should therefore be clinical, although serial MRI at 6- to 12-month intervals is a useful secondary end point in providing an index of pathological progression. In trials of patients presenting with clinically isolated syndromes suggestive of MS, MRI findings can be used in the entry criteria, and as a secondary outcome measure, but conversion to clinically definite MS should be the primary outcome. The pathological substrates of irreversible disability are demyelination and axonal loss. Putative magnetic resonance markers for these processes include decreased N-acetylaspartate on proton magnetic resonance spectroscopy, decreased magnetization transfer ratios, hypointensity on T1-weighted images, and loss of short T2 water fractions, some of which relate more closely to disability than conventional MRI findings. Further technical developments should lead to more accurate quantitation, greater pathological specificity, and stronger clinical correlations.

Acute myelopathy of unknown aetiology: a clinical, neurophysiological and MRI study of short- and long-term prognostic factors

Brain and spinal cord magnetic resonance imaging (MRI), multimodal evoked potentials (EPs) and cerebrospinal fluid (CSF) analysis were performed in 27 patients with acute myelopathy of unknown aetiology (AMUA), to detect the diagnostic and prognostic values of paraclinical tests at presentation. Spinal cord MRI was abnormal in 56% and brain MRI in 33% of the patients. Visual EPs were abnormal in 7%, median somatosensory EPs in 17%, tibial somatosensory EPs in 56% and motor EPs in 35% of the cases examined. Brain-stem acoustic EPs were normal in all the patients. CSF oligoclonal bands (OBs) were detected in 30% of cases. The patients were divided into subgroups according to the short-term clinical outcome (complete, partial or absent recovery). There were no significant differences among the three groups as regards MRI findings. Patients with complete recovery showed a significantly lower frequency of tibial somatosensory EP and motor EP abnormalities. According to the paraclinical findings at onset and on the basis of a long-term clinical follow-up (mean duration 24 months), 6 patients were diagnosed as having clinically definite multiple sclerosis, while 21 did not develop further neurological disturbances. Only the presence of CSF OBs was significantly more frequent in patients with definite multiple sclerosis. Our study indicates that EPs exploring spinal cord function are more powerful than spinal MRI for predicting the short-term outcome of AMUA, while the combined use of brain MRI and CSF OBs has the highest negative predictive value for the subsequent development of clinically definite multiple sclerosis.

The clinical and paraclinical profile of optic neuritis: a prospective study

To define the clinical and paraclinical profile of optic neuritis (ON), patients with a suspicion of ON among a population of 1.5 million were examined over 2.5 years. A diagnosis of monosymptomatic ON was established in 74 patients. Cerebrospinal fluid (CSF) studies in 73 patients revealed oligoclonal IgG bands in 67% and 32 of 60 patients examined (53%) had three or more high signal lesions on magnetic resonance imaging (MRI). A strong correlation was found between oligoclonal bands and abnormal MRI. In 52 patients, two or more CSF examinations revealed strong variations in individual patients for mononuclear cell count and IgG index. In contrast, of 39 patients with oligoclonal bands in the first sample, none showed the disappearance of bands, and of 13 patients initially negative for bands, only one developed bands. There was no correlation between exacerbation or remission and CSF findings. During a short-term follow-up of 6-40 months, 19 patients converted to MS.

Bilateral simultaneous optic neuropathy in adults: clinical, imaging, serological, and genetic studies

To elucidate the cause(s) of acute or subacute bilateral simultaneous optic neuropathy (BSON) in adult life, a follow up study of 23 patients was performed with clinical assessment, brain MRI, HLA typing, and mitochondrial DNA analysis. The results of CSF electrophoresis were available from previous investigations in 11 patients. At follow up, five (22%) had developed clinically definite multiple sclerosis, four (17%) had mitochondrial DNA point mutations indicating a diagnosis of Leber's hereditary optic neuropathy (LHON). The remaining 14 patients (61%) still had clinically isolated BSON a mean of 50 months after the onset of visual symptoms: three of 14 (21%) had multiple MRI white matter lesions compatible with multiple sclerosis, three of 14 (21%) had the multiple sclerosis associated HLA-DR15/DQw6 haplotype, and one of seven tested had CSF oligoclonal IgG bands; in total only five (36%) had one or more of these risk factors. The low frequency of risk factors for the development of multiple sclerosis in these 14 patients suggests that few will develop multiple sclerosis with more prolonged follow up. It is concluded that: (a) about 20% of cases of BSON without affected relatives are due to LHON; (b) multiple sclerosis develops after BSON in at least 20% of cases, but the long term conversion rate is likely to be considerably less than the rate of over 70% seen after an episode of acute unilateral optic neuritis in adult life.

Optic neuritis: findings on MRI, CSF examination and HLA class II typing in 60 patients and results of a short-term follow-up

Optic neuritis (ON) is a common first manifestation of multiple sclerosis (MS), and examination of patients with ON provides opportunities to study the early clinical stages of MS. This prospective study compares results of brain magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) examinations and HLA-Dw2 phenotyping in 60 consecutive patients with ON. At a median of 17 days after the onset of ON, 69% had oligoclonal IgG bands, and at a median on 79 days after onset, 53% had multiple (> or = 3) white matter lesions on MRI. Subgroup analyses revealed that MRI abnormalities and oligoclonal IgG bands were equally common in patients examined early or late after the onset of ON. Strong correlations were found between the presence of MRI abnormalities and oligoclonal IgG bands. The HLA-Dw2 phenotype was significantly increased in ON patients compared with controls, but also significantly different from a group of MS patients from the same geographical area. A significant relation was found between Dw2 phenotype and oligoclonal IgG bands. During a mean follow-up time of about 2 years, the diagnosis in 17 of the patients changed to clinically definite MS. Initially, 16 of them had oligoclonal IgG bands and 12 had three or more MRI lesions. Both MRI and CSF studies are important diagnostic tools in the workup of ON patients.

Sensitivities and predictive values of paraclinical tests for diagnosing multiple sclerosis

The sensitivities and predictive values of visual, somatosensory, and brain auditory evoked potentials (EPs), cerebrospinal fluid oligoclonal banding (CSF-OB) and magnetic resonance imaging (MRI) were evaluated for the early diagnosis of clinically definite multiple sclerosis (CDMS). Paraclinical evidence of asymptomatic lesions allows a diagnosis of CDMS. Eighty-two patients in whom MS was suspected but diagnosis of CDMS was not possible entered the study prospectively. Paraclinical examinations were performed at entry. Patients were examined and underwent EPs every 6 months, and MRI yearly. After a mean follow-up of 2.9 years, 28 patients (34%) had developed CDMS (McDonald-Halliday criteria). The initial MRI was strongly suggestive of MS in 19 of these (68%), while 27 (96%) had at least one MS-like abnormality in the initial MRI. CSF-OB and EPs had lower sensitivities. CDMS developed during follow-up in 19 of the 36 patients (53%) who had an initial MRI strongly suggestive of MS but in only 1 of the 25 who had normal MRI when first studied. These results support previous conclusions that MRI is the most sensitive test for detecting white matter asymptomatic lesions, and the most predictive for the diagnosis of CDMS.

The effect of corticosteroids for acute optic neuritis on the subsequent development of multiple sclerosis. The Optic Neuritis Study Group

BACKGROUND

Optic neuritis is often the first clinical manifestation of multiple sclerosis, but little is known about the effect of corticosteroid treatment for optic neuritis on the subsequent risk of multiple sclerosis.

METHODS

We conducted a multicenter study in which 389 patients with acute optic neuritis (and without known multiple sclerosis) were randomly assigned to receive intravenous methylprednisolone (250 mg every six hours) for 3 days followed by oral prednisone (1 mg per kilogram of body weight) for 11 days, oral prednisone (1 mg per kilogram) alone for 14 days, or placebo for 14 days. Neurologic status was assessed over a period of two to four years. The patients in the first group were hospitalized for three days; the others were treated as outpatients.

RESULTS

Definite multiple sclerosis developed within the first two years in 7.5 percent of the intravenous-methyl-prednisolone group (134 patients), 14.7 percent of the oral-prednisone group (129 patients), and 16.7 percent of the placebo group (126 patients). The adjusted rate ratio for the development of definite multiple sclerosis within two years in the intravenous-methylprednisolone group was 0.34 (95 percent confidence interval, 0.16 to 0.74) as compared with the placebo group and 0.38 (95 percent confidence interval, 0.17 to 0.83) as compared with the oral-prednisone group. The beneficial effect of the intravenous-steroid regimen appeared to lessen after the first two years of follow-up. Signal abnormalities on magnetic resonance imaging (MRI) of the brain were a strong indication of risk for the development of definite multiple sclerosis (adjusted rate ratio in patients with three or more lesions, 5.53; 95 percent confidence interval, 2.41 to 12.66). The beneficial effect of treatment was most apparent in patients with abnormal MRI scans at entry.

CONCLUSIONS

In patients with acute optic neuritis, treatment with a three-day course of high-dose intravenous methylprednisolone (followed by a short course of prednisone) reduces the rate of development of multiple sclerosis over a two-year period.