Visual evoked responses and immunoglobulin abnormalities in the diagnosis of multiple sclerosis

Evoked potentials and CSF-immunoglobulins in MS: relationship to disease duration, disability, and functional status

In 100 MS patients, BAEP and tibial SEP abnormality rates increased significantly with disease duration and clinical disability. VEP correlated non-linearly with disease duration, and median nerve SEP correlated with disability. In multifactorial analysis, however, BAEP correlated significantly only with clinical brainstem and cerebellar signs. These results suggest that evoked potentials correlate more strongly with neurological status of the functional subsystems than either overall disability or disease duration. These findings indirectly suggest that evoked potentials may be useful monitors during large therapeutical trials in MS patients.

Contrast sensitivity in multiple sclerosis measured by Cambridge Low Contrast Gratings: a useful clinical test?

The Cambridge Low Contrast Gratings (CLCG) were used to assess contrast sensitivity (CS) in 39 patients with clinically definite multiple sclerosis and 60 control subjects. CS was determined in both horizontal and vertical orientations and compared with visual evoked responses (VERs) in the same populations. Only 33% of patients had abnormal CS whereas 82% had abnormal VERs. There was no correlation between the degree of abnormalities in CS and VERs. There was no significant difference between CS determined in the vertical and horizontal orientation; however, examination in the vertical orientation increased the number of abnormalities detected by 2 (5%). We conclude that although CS, using the CLCG, is abnormal in a proportion of multiple sclerosis patients its detection is not clinically useful and is insensitive as a measure of subclinical optic neuropathy in multiple sclerosis.

Multiple sclerosis: diagnostic value of computerized tomography with delayed scanning after a double-dose of contrast medium in comparison with other diagnostic tests

In 63 cases of clinical definite or suspected MS we compared the results of CSF analysis, VEP, BAEP, CT scanning without and after double dose contrast, in 17 cases also those of MRT. We found that CSF analysis had the highest rate of abnormal findings, followed by MRT. VEP and CT with double dose contrast showed similar sensitivity, while BAEP and CT without contrast had disappointing results. We think that CT with delayed scanning after double dose contrast can be a very useful investigation in early and doubtful cases of MS, until MRT will become a more widespread and less expensive investigation.

Evoked potentials in suspected multiple sclerosis: diagnostic value and prediction of clinical course

Pattern visual, somatosensory and brainstem auditory evoked potentials (EPs) of 14 patients with definite multiple sclerosis, 222 patients suspected of having multiple sclerosis, 26 patients with isolated optic neuritis and 40 patients with a chronic not diagnosed neurologic disorder, were compared with their clinical diagnoses on 2 1/2-year follow-up. In the MS suspects, an EP abnormality demonstrating a clinically silent lesion in any modality (65 patients) was associated with a 71% chance of clinical deterioration (48% chance of definite MS within the follow-up period). Normal EPs (121 patients) were associated with a 16% chance of deterioration (4% chance of definite MS). EPs in patients in whom the only abnormalities confirmed known lesions (36 patients) did not predict follow-up status. Visual EPs demonstrated clinically silent lesions more frequently than somatosensory and auditory EPs (22%, 12% and 5% of patients). Only one of the patients with optic neuritis and 3 of the chronic not diagnosed group had EPs demonstrating clinically silent lesions. CSF and NMR studies also correlated with follow-up in subseries of the patients.

Clinical neurophysiology in the assessment of neurological symptoms in systemic lupus erythematosus

Neurophysiological studies were performed on 22 randomly selected patients with systemic lupus erythematosus in order to determine whether this form of assessment might be of value in the diagnosis and management of neurological lupus. Sixteen patients described neurological lupus. In eight, neurological symptoms were present at the time of neurophysiological testing. All eight had neurophysiological abnormalities. In six the abnormality was of central origin manifesting as a disorder of either visual evoked response (VER) or brain-stem auditory evoked response (BAER). In the remaining two, an isolated disorder of peripheral nerve conduction (PNC) was present. In the eight patients with previous neurological symptoms five (63%) had neurophysiological abnormalities, but a central disorder was observed in only one and abnormal PNC was present in all. Of the six patients with no neurological symptoms, three (50%) had central neurophysiological disorders. No correlation between individual neurophysiological disorders and specific neurological symptoms was observed. However, all four patients with active vasculitis and all seven with lymphopenia had a neurophysiological disorder. If these observations are extended and confirmed, neurophysiological studies may provide a useful test to the clinician in the evaluation and management of neurological lupus.

An evaluation of laboratory investigations in patients with multiple sclerosis

The contribution of VEP, CT and oligoclonal bands (OB) to the diagnosis of MS was studied in a group of 213 hospitalized patients. Whereas the diagnostic values of VEP and OB were both in the same range, the combination of both methods increased the proportion of cases with "definite MS" from 58 to 75%, whereas CT did not contribute significantly to diagnostic ascertainment. Vitamin B12 absorption was less than 10% in 27% of cases. A slight tendency towards increased serum IgG and IgM levels was found, and the rheumatoid factor was demonstrated in 6% of cases.

Suspected and clinically definite multiple sclerosis: the relationship between CSF immunoglobulins and clinical course

CSF immunoglobulins were examined in 103 patients with clinically definite multiple sclerosis, 106 patients with either suspected or progressive possible multiple sclerosis and 72 patients with other neurological diseases. Raised CSF IgG index and oligoclonal banding were found in 71% and 75% of clinically definite multiple sclerosis patients respectively and both tests were abnormal in 11% of patients with other neurological diseases. The CSF IgG index and the presence of oligoclonal IgG did not relate to the severity or duration of established disease in these patients. In patients with suspected and progressive possible multiple sclerosis, both a raised IgG index and the presence of oligoclonal banding were found significantly more frequently than in the OND group. Abnormalities of these parameters were significantly correlated with the presence of an abnormal evoked response in these patients (chi 2 = 10.16 p less than 0.01). When 47 patients with suspected multiple sclerosis were studied prospectively the presence of oligoclonal banding at presentation was associated with development of further disease activity.

Multiple sclerosis: incorporation of results of laboratory techniques in the diagnosis

In a retrospective study of 100 multiple sclerosis patients we compared the diagnostic classification according to the Schumacher/Rose criteria and the newest criteria, proposed by Poser et al. It is clear that by incorporating the results of laboratory investigations in the diagnostic criteria a firm diagnosis of multiple sclerosis can be reached more often and at an earlier stage of the disease. Evaluating abnormal laboratory findings, we found that it was possible to detect more than 90% of diagnostically important findings, i.e. findings effecting a change in diagnostic classification (from possible multiple sclerosis to probable or definite, from probable to definite), using only two of the laboratory tests: cerebrospinal fluid analysis and visual evoked response. Because the results of laboratory tests contributing to diagnostic classification are not specific for multiple sclerosis, the importance of evaluating the complete differential diagnosis of diseases that can be confused with multiple sclerosis is stressed.

Clinical correlates of abnormal brain-stem auditory evoked responses in multiple sclerosis

Brain-stem auditory evoked responses (BAERs) were examined in 178 patients with multiple sclerosis (MS) and compared to the frequency of abnormalities in visually evoked responses (VERs) and in CSF electrophoresis. In clinically definite MS, BAERs were abnormal in 61% and a significant relationship was noted between disability due to MS and the frequency and severity of BAER abnormalities. In suspected MS, BAERs showed evidence of a second lesion in 14% whereas VERs indicated a second lesion in 24%. Abnormal BAERs in patients with suspected MS with brain-stem signs were significantly associated with the presence of truncal and limb ataxia. In progressive possible MS, abnormal BAERs were found in 49% but indicated a second lesion in 35% of patients and were significantly related to the duration of illness. In progressive possible MS, abnormal VERs but not abnormal BAERs, were significantly associated with the presence of CSF oligoclonal IgG banding. Normal BAERs in association with clinical brain-stem abnormalities were found in 24% of patients with clinically definite MS, 50% with suspected MS and 33% with progressive possible MS.