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Due to an unexpected increase in serious cardiovascular events in MS patients treated with Linomide, a synthetic immunomodulator, two phase-III multinational relapsing remitting (RR) and secondary progressive (SP) MS trials had to be discontinued. MRI results of 413 patients who participated for at least 3 months were analysed. Patients received placebo, 2.5 or 5 mg Linomide. Scans were performed at pre-enrolment, month 3 and termination. The number and volume of enhancing lesions (ELV), and the number of active scans were evaluated. At month 3, the decrease in the number of enhancing lesions in the placebo group was 11%, compared with 15% in the 2.5 mg group (P=0.027) and 23% in the 5 mg group (P=0.057). Using the percentage of active scans as outcome parameter, the odds ratio for improvement between placebo and 2.5 mg group was 1.62 (P=0.14); between placebo and 5 mg Linomide group 3.58 (P=0.003). At termination, a rebound effect was noted in the 2.5 mg group (P=0.01). Analysis of the ELV showed no significant difference between placebo and treatment groups. Although Linomide has unacceptable side effects, it seems to have a modest effect on MS disease activity, as measured by MRI. Multiple Sclerosis (2000) 6, 99 - 104

The authors compare the spinal cord magnetization transfer ratio (MTR) of multiple sclerosis (MS) patients to healthy volunteers, relate MTR to spinal cord atrophy, and relate these and other magnetic resonance (MR) imaging parameters to disability. Sixty-five patients with MS (14 relapsing remitting [RR], 34 secondary progressive [SP], and 17 primary progressive [PP] MS), and 9 healthy volunteers were studied using MR at 1.0 T. Disability of the patients was assessed using the expanded disability status scale (EDSS). Magnetic resonance parameters were upper spinal cord MTR, number of focal spinal lesions, presence of diffuse abnormalities, and spinal cord cross-sectional area (CSA). Correlations were assessed using Spearman's rank correlation coefficient (r). Magnetization transfer ratio was higher in the controls (median, 33%; range, 30%-38%) than in patients with MS (median, 30%; range, 16-36; p < 0.05). In patients with MS EDSS correlated with spinal cord MTR, albeit weakly (r = -0.25, p < 0.05). Correlation between EDSS and spinal cord CSA was better (SRCC = -0.40, p < 0.01). No correlation was found between MTR and CSA (r = 0.1, p = 0.4). Combining MTR with spinal cord CSA improved correlation with EDSS (r = -0.46, p < 0.001), suggesting an independent correlation between disability and these 2 MR parameters. Expanded disability status scale scores were higher in patients who had diffuse spinal cord abnormality regardless of focal lesions (median, 6; range, 1.5-7.5) than in patients without diffuse abnormalities (median, 3.5; range, 0-8; p < 0.01). CSA was lower in patients with diffuse spinal cord abnormality (median, 62; range, 46-89 mm2) than in patients without diffuse abnormalities (median, 73; range, 47-89 mm2; p < 0.01). MTR was slightly lower in patients with diffuse spinal cord abnormalities (median, 29; range, 21%-33%) than in patients without diffuse abnormalities (median, 31; range, 16-36; t-test, p < 0.05).

The current optimal imaging protocol in spinal cord MR imaging in patients with multiple sclerosis includes a long TR conventional spin-echo (CSE) sequence, requiring long acquisition times. Using short tau inversion recovery fast spin-echo (fast STIR) sequences both acquisition time can be shortened and sensitivity in the detection of multiple sclerosis (MS) abnormalities can be increased. This study compares both sequences for the potential to detect both focal and diffuse spinal abnormalities. Spinal cords of 5 volunteers and 20 MS patients were studied at 1.0 T. Magnetic resonance imaging included cardiac-gated sagittal dual-echo CSE and a cardiac-gated fast STIR sequence. Images were scored regarding number, size, and location of focal lesions, diffuse abnormalities and presence/hindrance of artifacts by two experienced radiologists. Examinations were scored as being definitely normal, indeterminate, or definitely abnormal. Interobserver agreement regarding focal lesions was higher for CSE (kappa = 0.67) than for fast STIR (kappa = 0.57) but did not differ significantly. Of all focal lesions scored in consensus, 47% were scored on both sequences, 31% were only detected by fast STIR, and 22% only by dual-echo CSE (n.s.). Interobserver agreement for diffuse abnormalities was lower with fast STIR (kappa = 0.48) than dual-echo CSE (kappa = 0.65; n. s.). After consensus, fast STIR showed in 10 patients diffuse abnormalities and dual-echo CSE in 3. After consensus, in 19 of 20 patients dual-echo CSE scans were considered as definitely abnormal compared with 17 for fast STIR. The fast STIR sequence is a useful adjunct to dual-echo CSE in detecting focal abnormalities and is helpful in detecting diffuse MS abnormalities in the spinal cord. Due to the frequent occurrence of artifacts and the lower observer concordance, fast STIR cannot be used alone.

We examined the value of spinal cord magnetic resonance imaging (MRI) in the diagnostic work-up of multiple sclerosis (MS). Forty patients suspected of having MS were examined within 24 months after the start of symptoms. Disability was assessed, and symptoms were categorized as either brain or spinal cord. Work-up further included cerebrospinal fluid analysis and standard proton-density, T2-, and T1-weighted gadolinium-enhanced brain and spinal cord MRI. Patients were categorized as either clinically definite MS (n = 13), laboratory-supported definite MS (n = 14), or clinically probable MS (n = 4); four patients had clinically probable MS, and in nine MS was suspected. Spinal cord abnormalities were found in 35 of 40 patients (87.5 %), consisting of focal lesions in 31, only diffuse abnormalities in two, and both in two. Asymptomatic spinal cord lesions occurred in six patients. All patients with diffuse spinal cord abnormality had clear spinal cord symptoms and a primary progressive disease course. In clinically definite MS, the inclusion of spinal imaging increased the sensitivity of MRI to 100 %. Seven patients without a definite diagnosis had clinically isolated syndromes involving the spinal cord. Brain MRI was inconclusive, while all had focal spinal cord lesions which explained symptoms and ruled out other causes. Two other patients had atypical brain abnormalities suggesting ischemic/vascular disease. No spinal cord abnormalities were found, and during follow-up MS was ruled out. Spinal cord abnormalities are common in suspected MS, and may occur asymptomatic. Although diagnostic classification is seldom changed, spinal cord imaging increases diagnostic sensitivity of MRI in patients with suspected MS. In addition, patients with primary progressive MS may possibly be earlier diagnosed. Finally, differentiation with atypical lesions may be improved.

Magnetic resonance imaging (MRI) monitoring of disease progression in multiple sclerosis is limited by the lack of correlation of abnormalities seen on T2-weighted imaging, and disability. We studied the histopathology of multiple sclerosis lesions, as depicted by MRI, in a large postmortem sample, focusing on axonal loss. Tissue samples from 17 patients were selected immediately postmortem for histopathological analysis on the basis of T2-weighted imaging, including normal appearing white matter and T1 hypointense lesions. In each region, we measured magnetization transfer ratios (MTR), T1 contrast ratio, myelin, and axonal density. T2 lesions (109 samples) were heterogeneous with regard to MRI appearance on T1 and MTR, whereas axonal density ranged from 0% (no residual axons) to 100% (normal axonal density). Of 64 T2 lesions, 17 were reactive (mild perivascular inflammation only), 21 active, 15 chronically active, and 11 chronically inactive. MTR and T1 contrast ratio correlated strongly with axonal density. Also in normal appearing white matter (24 samples), MTR correlated with axonal density. In conclusion, postmortem tissue sampling by using MRI revealed a range of pathology, illustrating the high sensitivity and low specificity of T2-weighted imaging. T1 hypointensity and MTR were strongly associated with axonal density, emphasizing their role in monitoring progression in multiple sclerosis.

We describe seven Dutch patients from six families with a slowly progressive, mainly spinal cord syndrome that remained for many years the sole expression of cerebrotendinous xanthomatosis (CTX). MRI demonstrated white matter abnormalities in the lateral and dorsal columns of the spinal cord. Post-mortem examination of one of the patients showed extensive myelin loss in these columns. An array of genotypes was found in these patients. We conclude that 'spinal xanthomatosis' is a clinical and radiological separate entity of CTX that should be included in the differential diagnosis of 'chronic myelopathy'.

Objective: To evaluate whether degree of inflammatory activity in multiple sclerosis, expressed by frequency of gadolinium enhancement, has prognostic value for development of hypointense lesions on T1-weighted spin-echo magnetic resonance images, a putative marker of tissue destruction., Design: Cohort design with long-term follow-up. Thirty-eight patients with multiple sclerosis who in the past had been monitored with monthly gadolinium-enhanced magnetic resonance imaging for a median period of 10 months (range, 6-12 months) were reexamined after a median period of 40.5 months (range, 33-80 months)., Setting: Magnetic Resonance Center for Multiple Sclerosis Research, Amsterdam, the Netherlands, referral center., Main Outcome Measures: The new enhancing lesion rate (median number of gadolinium-enhancing lesions per monthly scan) during initial monthly follow-up; hypointense T1 and hyperintense T2 lesion load at first and last visit., Results: The number of enhancing lesions on entry scan correlated with the new enhancing lesions rate (r = 0.64; P<.001, Spearman rank correlation coefficient). The new enhancing lesion rate correlated with yearly increase in T1 (r = 0.42; P<.01, Spearman rank correlation coefficient) and T2 (r = 0.47; P<.01, Spearman rank correlation coefficient) lesion load. Initial T1 lesion load correlated more strongly with yearly increase in T1 lesion load (r = 0.68; P<.01, Spearman rank correlation coefficient)., Conclusions: Degree of inflammatory activity only partially predicted increase in T1 (and T2) lesion load at long-term follow-up. Initial T1 lesion load strongly contributed to subsequent increase in hypointense T1 lesion load, suggesting that there is a subpopulation of patients with multiple sclerosis who are prone to develop destructive lesions.

Although fatigue is a frequent complaint of patients with multiple sclerosis (MS), little is known about the origins of multiple-sclerosis-associated fatigue. Our primary focus was to study if the extent of cerebral abnormalities, as shown on magnetic resonance imaging (MRI), had any relation with the frequency and intensity of fatigue complaints of patients with a definite diagnosis of MS. Fatigue severity was rated by the patients with the use of a 2-week diary and a fatigue questionnaire, while conventional T1- and T2-weighted MRI provided several measures for cerebral abnormalities. In total, 72% of 45 patients reported to be seriously fatigued at least several times a week over the last 3-month period. Fatigue severity was not related to the total extent of cerebral abnormalities, or to MRI-based atrophy measures. Regional lesion load did not differ between fatigued and non-fatigued subjects. Although neurological disability, as measured by the Expanded Disability Status Scale (EDSS) and Neurological Rating Scale (NRS), did correlate significantly with most MRI measures, it showed no relation with fatigue severity. Neurological progression rates and number of exacerbations in the 2-year period prior to assessment were not significantly associated with the fatigue measures. Therefore, our findings suggest that differences in levels of self-reported fatigue in patients with multiple sclerosis cannot merely be explained by the degree of clinical disease activity, neurological disability or the extent of MRI abnormalities. These results are compared to other research findings and the possible role of alternative factors influencing fatigue in multiple sclerosis are discussed.

Purpose: To study whether application of magnetization transfer contrast (MTC) improves visibility and detection of multiple sclerosis (MS) lesions on long repetition time (TR) conventional spin-echo (CSE) or fast spin-echo (FSE) magnetic resonance (MR) imaging., Material and Methods: In 20 patients and 5 controls, MR images were obtained using long repetition time CSE and FSE sequences with and without MTC. Signal-to-noise ratios of normal appearing white matter (NAWM) and selected lesions, and contrast-to-noise ratios between lesions and NAWM, were calculated. Lesions were counted and total lesion volume was measured in a blinded fashion for each sequence., Results: In controls, MT effect in white matter (16.3% vs. 12.2%) was higher for CSE than for FSE (p < 0.01). Application of MTC to either CSE or FSE resulted in a significantly lower decrease in signal intensity of NAWM in patients compared to white matter in controls (p < 0.01). Furthermore, in patients signal intensity of lesions was less decreased than signal intensity of NAWM (p < 0.01). Compared to sequences without MTC, contrast-to-noise ratios were significantly higher on both CSE (10.9%) and FSE (6.3%) when MTC was applied (p < 0.01). Despite better visibility, the number of lesions detected on either sequences did not increase when MTC was applied. For CSE with MTC, we found an almost equal number of lesions and for FSE with MTC, we found even less lesions (p < 0.01). Total lesion volume did not change significantly when MTC was applied., Conclusion: Although contrast between lesions and NAWM improved when magnetization transfer contrast was applied, this did not increase detection of MS lesions on either CSE or FSE MR imaging.

We investigated various magnetic resonance MRI parameters for both brain and spinal cord to see if any improved the clinicoradiological correlation in multiple sclerosis. Ninety-one multiple sclerosis patients (28 relapsing-remitting, 32 secondary progressive and 31 primary progressive) were imaged using conventional T1, proton density- and T2-weighted MRI of the brain and spinal cord. Focal brain and spinal cord lesion load was scored, as were diffuse signal abnormalities, brain ventricular volume and spinal cord cross-sectional area. Clinical measures included the expanded disability status scale (EDSS), the functional systems score and a dedicated urology complaint questionnaire. Secondary progressive patients differed from relapsing-remitting and primary progressive patients by a larger number of hypointense T1 lesions in the brain, ventricular enlargement and spinal cord atrophy. Primary progressive patients more often had diffuse abnormalities in the brain and/or spinal cord than did relapsing-remitting and secondary progressive patients. In the entire study population, EDSS correlated with both brain and spinal cord MRI parameters, which were independent. The urological complaint score correlated only with spinal cord MRI parameters. In relapsing-remitting and secondary progressive multiple sclerosis, the correlation between MRI and clinical parameters was better than in the entire population. In this subgroup EDSS variance could be explained best by T1 brain lesion load, ventricle volume and spinal cord cross-sectional area. In the primary progressive subgroup the clinicoradiological correlation was weak for brain parameters but was present between spinal cord symptoms and spinal cord MRI parameters. In conclusion, the different brain and spinal cord MRI parameters currently available revealed considerable heterogeneity between clinical subtypes of multiple sclerosis. In relapsing-remitting and secondary progressive multiple sclerosis both brain and spinal cord MRI may provide a tool for monitoring patients, while in primary progressive multiple sclerosis the clinicoradiological correlation is weak for brain imaging.

Purpose: We evaluated the appearance of enhancing multiple sclerosis (MS) lesions on unenhanced T1-weighted MR images and the natural course of enhancing MS lesions on serial unenhanced T1-weighted and magnetization transfer (MT) MR images., Methods: One hundred twenty-six enhancing lesions were followed up monthly for 6 to 12 months to determine their signal intensity on unenhanced T1-weighted and MT MR images. At the time of initial enhancement, the size of the lesion and the contrast ratio of enhancement were calculated for each enhancing lesion. During follow-up, the contrast ratio on the corresponding unenhanced T1-weighted image was measured, and an MT ratio (MTR) was calculated., Results: Twenty-five enhancing lesions (20%) appeared isointense and 101 lesions (80%) appeared hypointense relative to normal-appearing white matter on unenhanced T1-weighted images. During 6 months of follow-up, four MR patterns of active lesions were detected: initially isointense lesions remained isointense (15%); initially isointense lesions became hypointense (5%, most of which reenhanced); initially hypointense lesions became isointense (44%); and initially hypointense lesions remained hypointense (36%). MTR was significantly lower for hypointense lesions as compared with isointense lesions at the time of initial enhancement. For lesions that changed from hypointense to isointense, MTR increased significantly during 6 months of follow-up. Multiple regression analysis showed that strongly decreased MTR at the time of initial enhancement and enhancement duration of more than one scan were predictive of a hypointense appearance on unenhanced T1-weighted images at 6 months' follow-up. Ring enhancement was found to be the only (weak) predictor of persistently hypointense signal intensity., Conclusion: Most enhancing lesions appear slightly to significantly hypointense on unenhanced T1-weighted images. Although most hypointensities are reversible, only those lesions that fail to recover on unenhanced T1-weighted and MT images may have considerable irreversible structural changes.

Purpose: We compared conventional spin-echo (CSE) with fast spin-echo (FSE) dual-echo MR images to determine which of these sequences was better able to depict spinal cord abnormalities in patients with multiple sclerosis (MS)., Methods: CSE and FSE dual-echo MR images were obtained in 37 patients with MS and in six healthy control subjects, all of whom were examined on a 1.0-T MR unit with a phased-array coil and cardiac triggering. Two blinded interpreters graded the MR studies, first separately and then by consensus. Images were scored for presence of artifacts, number of focal lesions, and presence of a diffuse increase in signal intensity., Results: No abnormalities were seen in the volunteers. The CSE sequences were significantly less hindered by MR imaging artifacts than were the FSE sequences. Interobserver agreement was slightly higher for the CSE than the FSE sequences. After reaching a consensus, the observers found that both CSE and FSE techniques enabled detection of approximately the same number of focal lesions; however, in three patients, small single lesions seen on the CSE images were missed on the FSE images. Also, depiction of a diffuse increase in signal intensity was better on the CSE images. As a result, more patients had abnormal findings on the CSE sequences than on the FSE sequences (35 versus 31)., Conclusion: Cardiac-triggered dual-echo FSE sequences are almost as good as CSE sequences for depicting spinal MS lesions. Therefore, in cases of established spinal MS, FSE techniques may be as effective as CSE techniques. Because sensitivity for subtle abnormalities is lower with FSE imaging, CSE remains the preferred technique for patients with suspected MS of the spinal cord.

We evaluated the effect of interscanner variation on brain MRI-measured lesion volumes and measurement reproducibility in MS. Twenty clinically definite MS patients were each scanned on two or three scanners (a total of 14 scanners were used). In addition, a formalin-fixed MS brain was studied on eight scanners from different manufacturers and with different field strengths. For the formalin-fixed MS brain, on each machine we obtained two scans with slice thicknesses of 5 and 3 mm. Only 5-mm-thick slices were obtained from patients. The lesion volume present on each scan was evaluated three times by a single observer in random order, using a local thresholding technique. In two groups of eight patients scanned on machines with different field strengths, the mean lesion volumes present on scans obtained at 1.5 T were significantly higher than those measured on scans obtained with machines operating at 0.5 and 1.0 T (p < 0.01). When a single observer repeatedly evaluated the same scan, a median introbserver agreement of 98.7% (95% CI, 97.9 to 99.1) was achieved. However, when the observer evaluated the scans from different MRI scanners, the agreement (an interscanner agreement) fell to 91.1% (CI, 90.2 to 94.1). When only scanners operating at 1.5 T were considered, the median interscanner agreement was 96.7% (CI, 95 to 97.5). Also, for the formalin-fixed MS brain, the intraobserver agreements obtained with both slice thicknesses were significantly higher than the corresponding interscanner agreements. The interscanner agreement, but not the intraobserver agreement, obtained with a slice thickness of 3 mm was higher than that obtained with a slice thickness of 5 mm. Our results indicate that lesion volume measurements in MS are influenced significantly by the use of different MR scanners and that a patient included in a serial study should be always scanned with the same MR machine using 3-mm thick slices.

Purpose: To compare the efficacy of single-dose gadolinium with magnetization transfer contrast (MTC) with that of triple-dose gadolinium in detecting enhancing multiple sclerosis lesions., Methods: Twenty-one patients with multiple sclerosis were examined with MR imaging first with 0.1 mmol/kg gadolinium (single dose) and then, after 24 to 72 hours, with 0.3 mmol/kg gadolinium (triple dose). T2-weighted fast spin-echo and T1-weighted spin-echo MR images with and without MTC were obtained before contrast administration followed by either T1-weighted spin-echo images with MTC (single dose) or conventional T1-weighted spin-echo images (triple dose), starting 5, 17, and 29 minutes after contrast administration. All images were evaluated in a blinded fashion and scored in random order by two readers. Outcome parameters included number of enhancing lesions, number of active MR examinations (those containing at least one enhancing lesion), contrast ratio (signal intensity of enhancing lesion divided by signal intensity of normal-appearing white matter), and size of enhancing lesions., Results: Eighty-one percent more enhancing lesions and 49% more active MR examinations were detected when a triple dose of gadolinium was used as compared with a single dose. The level of agreement between readers as to the number of enhancing lesions was significantly higher for triple-dose than for single-dose gadolinium. With triple-dose gadolinium, contrast ratios and areas of enhancement increased by 10% and 33%, respectively. Delayed imaging increased the size of the lesion by 11% on single-dose MTC images and by 18% on triple-dose images., Conclusion: Triple-dose gadolinium is more effective (higher sensitivity and interobserver agreement) than single-dose gadolinium in combination with MTC in detecting enhancing multiple sclerosis lesions.

Purpose: To determine whether the MR appearance of the spinal cord in patients with multiple sclerosis (MS) differs according to clinical subtype., Methods: The spinal cords of 20 healthy control subjects and 60 patients with MS (22 with relapsing-remitting disease, 22 with secondary-progressive disease, and 16 with primary-progressive disease) were examined with sagittal dual-echo spin-echo MR imaging and with axial T2*-weighted gradient-echo MR imaging. Two interpreters scored the images for focal lesions and for diffuse abnormalities. Cross-sectional areas of the cords were measured at the C-2 level., Results: No abnormalities were found in any of the control subjects nor in two of the patients. Fifty (83%) of 60 patients had focal lesions. Diffuse abnormality and focal lesions were found in 50% of patients with secondary-progressive MS, in 25% of patients with primary-progressive disease, and in 18% of patients with relapsing-remitting disease. Diffuse abnormality without focal lesions was found in seven patients with primary-progressive MS and in one patient with secondary-progressive MS. Patients with diffuse abnormalities had a smaller cross-sectional area of the spinal cord and they suffered from more disability than did patients without diffuse abnormalities., Conclusion: The MR appearance of the spinal cord differs among clinical subgroups of MS. Diffuse abnormality of the spinal cord is associated with a progressive clinical course and greater disability.

Background/aims: The aim was to study the reproducibility of magnetic resonance velocity mapping, when measuring portal vein and superior mesenteric artery blood flow, under fasting and post-prandial conditions. Magnetic resonance flow measurements for the portal vein were compared with echo-Doppler measurements in the right portal vein., Methods: Eight healthy volunteers were studied on two occasions, separated by 1 week. Blood flow in the portal vein and superior mesenteric artery was measured repeatedly under basal fasting conditions. On one occasion measurements were also made after a meal. Every magnetic resonance measurement was followed by an echo-Doppler measurement in the right portal vein. Correlations between flow values were calculated using Pearson's r. Variability components were assessed using ANOVA., Results: Intra-individual variability was approximately 7% for portal vein flow measurements using magnetic resonance velocity mapping. This variability did not increase after 1 h, 1 week and after a meal. Values of flow measured in the portal vein and superior mesenteric artery using magnetic resonance velocity mapping correlated well (r = 0.80, p < 0.001). Fasting portal flow as measured with magnetic resonance velocity mapping was 1.2 l/min (range 0.96-1.6 l/min). Variability in echo-Doppler measurements was comparable to the variability of magnetic resonance velocity mapping, and flow measurements obtained with the two techniques correlated well (r = 0.74; p < 0.001)., Conclusions: Magnetic resonance velocity mapping accurately measures blood flow in the portal vein with low variability and should be preferred when absolute flow values are necessary. Echo-Doppler measurement of the right portal vein has a low variability and can be used to study changes in flow.

The purpose of this study was, first, to evaluate correlations between four potential magnetic resonance (MR) parameters for severe tissue destruction in multiple sclerosis (MS) lesions. Second, to evaluate the effect of incidental magnetization transfer (MT) effect on hypointense lesions in multislice T1 spin echo (SE) imaging. In 49 lesions, from 10 MS patients, MT ratio (MTR), T1 relaxation time, signal intensity (SI) on T1-weighted SE images normalized to normal-appearing white matter (NAWM), and SI normalized to cerebrospinal fluid (CSF) were measured. Differences in contrast of hypointense lesions were measured between single slice and multislice imaging. MTR correlated significantly (p < .001) with longitudinal relaxation rates (1/T1) (r = 0.84), SI normalized to NAWM (r = 0.78), and SI normalized to CSF (r = 0.75). The degree of reduction in contrast, caused by multislice imaging, correlated significantly with MTR of lesions (r = 0.60, p < .001), leading to reduction of hypointense lesion load (p < .01). We conclude that all four MR markers for severe tissue destruction are highly correlated when applied to selected hypointense lesions on T1-weighted SE images. Due to "incidental" off-resonance excitation, contrast and hypointense lesion load will be reduced in multislice T1-weighted SE images.

Purpose: To compare cardiac-triggered dual-echo spin-echo and magnetization transfer-prepared gradient-echo (MT-GE) MR imaging in the detection of multiple sclerosis (MS) lesions in the spinal cord., Methods: The cervical spinal cord in 20 patients with MS and in nine healthy volunteers was examined with spin-echo and MT-GE MR imaging. Sagittal images were scored for number of lesions, certainty about lesions, image quality, and visual hindrance by artifacts in random order by two radiologists separately and in a blinded manner., Results: In one healthy volunteer, a lesion was seen on images obtained with both images. Lesion/cord contrast-to-noise ratio was equal on both the MT-GE and T2-weighted spin-echo images. MT-GE images showed better image quality and fewer artifacts than the spin-echo images did. The readers found approximately the same number of lesions. However, the number of definite lesions was higher for the spin-echo sequence than for the MT-GE sequence. One reader found 45 definite lesions with spin-echo and 34 definite lesions with MT-GE. For the other reader, these numbers were 37 (spin-echo) and 31 (MT-GE). On the spin-echo images, 90% of the patients were considered to have definite lesions; on the MT-GE images, the readers found definite lesions in 65% (reader 1) and in 70% (reader 2) of the patients., Conclusion: Image quality was better with the MT-GE technique than with the spin-echo technique, and lesion/cord contrast-to-noise ratio on the MT-GE images was equal to that of T2-weighted spin-echo images. However, for detecting spinal cord MS lesions in the sagittal plane, the spin-echo images were preferred to the MT-GE images.

Although the superiority of FLAIR over conventional T2-weighted spin-echo (SE) is still unclear, one potential advantage would be its use in quantitative lesion load measurements. We have observed a potential pitfall regarding the use of FLAIR in image quantification. We report a case where a part of the hyperintense lesions on T2 SE, which was hypointense on T1 SE, subsequently was found to be isointense to brain on FLAIR images. Therefore, quantification of lesion load by means of FLAIR might underestimate the "true" lesion load, as seen on T2 SE.