Double Inversion Recovery Sequence Research Articles

Assessment of the diagnostic accuracy of double inversion recovery sequence compared with FLAIR and T2W_TSE in detection of cerebral multiple sclerosis lesions.

BackgroundMultiple sclerosis (MS) is a demyelinating disease of the central nervous system. MRI has an important role in early diagnosis of MS within diagnostic criteria.AimTo determine the diagnostic value of the double inversion recovery (DIR) sequence in detection of brain MS lesions.MethodsIn this cross-sectional study, 55 patients were admitted to the MRI department in Vali-E-Asr Hospital in Qaemshahr, Iran, from May 2016 to February 2016. Imaging was performed on a 1.5T Philips MR system using DIR, fluid attenuated inversion recovery (FLAIR), and T2-weighted turbo spin echo (T2W_TSE) sequences with the same parameters, including field of view (FOV), matrix, slice thickness, voxel size, and number of signal averaging (NSA). The DIR sequence has two different time inversions (TI1=3400, TI2=325ms): suppressing cerebrospinal fluid (CSF) and white matter signal. Data analysis was performed using the SPSS version 20, and p-value was gained from the patient-wise analysis by Wilcoxon analysis and paired samples t-test for matched pairs.ResultsMore lesions in number and size were depicted on the DIR sequence compared with FLAIR (p=0.000 with a relative ratio of 6) and T2W_TSE (p=0.000 with a relative ratio of 10). DIR demonstrated significantly more intracortical lesions compared with FLAIR (p=0.000 with a relative ratio of 2.53) and T2W_TSE (p=0.000 and relative ratio of 8.87). There was significantly higher contrast ratio between the white matter lesions and the normal appearing white matter (NAWM) in all anatomical regions especially in deep white matter (p=0.001).ConclusionAn increasing total number of MS lesions can be detected by DIR sequence; thus, we recommend adding DIR sequence in routine MR protocols for MS patients.

Double inversion recovery imaging of the brain: deriving the most relevant sequence through real images.

We propose a practical method for setting the optimal inversion times (TI) for double inversion recovery (DIR) sequences. Our method used the measurement of signal intensity (SI) from real images to set the optimal TI for white-matter (WM) and gray-matter (GM)-attenuated inversion recovery (WAIR and GAIR, respectively) images.3D-DIR images of healthy volunteers were obtained on 1.5- and 3.0-T magnetic resonance (MR) scanners and the SIs of GM, WM, and cerebrospinal fluid (CSF) were evaluated on real images. We found TI2s at which the SI of WM or GM was null. Then, we found TI1+2 (=TI1+TI2) at which the SI of CSF was null. We defined the two TIs as optimal TIs. We assessed the utility of these TIs with additional volunteers and patients, and similar images were obtained with the determined TIs. Optimal TIs for DIR images could be efficiently determined using this method.

Qualitative analysis of double inversion recovery MRI in drug-resistant epilepsy

PurposeTo determine whether Double Inversion Recovery (DIR) on 3T MRI can enhance detection of epileptogenic lesions Methods: 29 adult patients with DRE were enrolled in a prospective pilot study. Brain MRIs were obtained using a specialized protocol that included: (1) Fast-Spin EchoT2, (2) T2 fluid attenuated inversion recovery (FLAIR), and (3) DIR sequences. Two neuroradiologists blinded to clinical information independently reviewed each sequence in the order listed above for T2-hyperintense lesions. Cortical lesions were determined to be concordant with the epileptic focus based upon available clinical and electrodiagnostic testing. Results: Of 29 studies, 21 had a lesion identified with 13/21 abnormalities being non-specific. Of 8 remaining studies, 3 revealed a lesion only with DIR sequencing. DIR-lesions were concordant with clinical data in 1 subject, non-discordant in 1 subject, and discordant in 1 subject. SignificanceDIR has the potential to be more sensitive in detecting cortically based lesions relative to standard imaging. More data are needed to assess the sensitivity and specificity of DIR, particularly as it pertains to identification of epileptogenic lesions using electrodiagnostic testing and outcome after surgery.

The value of qualitative and quantitative assessment of lesion to cerebral cortex signal ratio on double inversion recovery sequence in the differentiation of demyelinating plaques from non-specific T2 hyperintensities.

To assess the usefulness of the visual assessment and to determine diagnostic value of the lesion-to-cerebral cortex signal ratio (LCSR) measurement in the differentiation of demyelinating plaques and non-specific T2 hyperintensities on double inversion recovery (DIR) sequence. DIR and fluid-attenuated inversion recovery (FLAIR) sequences of 25 clinically diagnosed multiple sclerosis (MS) patients and 25 non-MS patients with non-specific T2-hyperintense lesions were evaluated visually and LCSRs were measured by two observers independently. On DIR sequence, the calculated mean LCSR ± SD for demyelinating plaques and non-specific T2-hyperintense lesions were 1.60 ± 0.26 and 0.75 ± 0.19 for observer1, and 1.61 ± 0.27 and 0.74 ± 0.19 for observer2. LCSRs of demyelinating plaques were significantly higher than other non-specific T2-hyperintense lesions on DIR sequence. By using the visual assessment demyelinating plaques were differentiated from non-specific T2-hyperintensities with 92.8% sensitivity, 97.5% specificity and 95.1% accuracy for observer1 and 92.8% sensitivity, 95% specificity and 93.9% accuracy for observer2. Visual assessment and LCSR measurement on DIR sequence seems to be useful for differentiating demyelinating MS plaques from supratentorial non-specific T2 hyperintensities. This feature can be used for diagnosis of MS particularly in patients with only supratentorial T2-hyperintense lesions who are categorized as radiologically possible MS. • Demyelinating plaques and non-specific T2-hyperintensities have different SI on DIR images. • These differences can be assessed by LCSR measurement or visual assessment. • There is an excellent inter-observer agreement for both methods. • This feature can be used in radiologically possible MS cases.

Detection of Epileptogenic Lesions Using MRI Double Inversion Recovery (DIR) Sequence in Patients with Drug-Resistant Epilepsy (DRE) (P4.183)

Detection of Epileptogenic Lesions Using MRI Double Inversion Recovery (DIR) Sequence in Patients with Drug-Resistant Epilepsy (DRE) (P4.183)

Length of optic nerve double inversion recovery hypersignal is associated with retinal axonal loss

Objectives: To assess the association between optic nerve double inversion recovery (DIR) hypersignal length and retinal axonal loss in neuroinflammatory diseases affecting optic nerves. Methods: We recruited patients previously affected (> 6 months) by a clinical episode of optic neuritis (ON). We had 25 multiple sclerosis (MS) patients, eight neuromyelitis optica spectrum disorder (NMOSD) patients and two patients suffering from idiopathic caused ON undergo brain magnetic resonance imaging (MRI); including a 3-dimensional (3D) DIR sequence, optical coherence tomography (OCT) examination and visual disability evaluation. Evaluation criteria were retinal thickness/volume, optic nerve DIR hypersignal length and high/low contrast vision acuity. Results: In the whole cohort, we found good associations (< 0.0001) between optic nerve DIR hypersignal length, peripapillary retinal nerve fiber layer thickness, inner macular layers volumes, and visual disability. We found subclinical radiological optic nerve involvement in 38.5% of non-ON MS eyes. Conclusions: Optic nerve DIR hypersignal length may be a biomarker for retinal axonal loss, easily applicable in routine and research on new anti-inflammatory or neuroprotective drug evaluation. Detection of subclinical ON with 3D-DIR in a non-negligible proportion of MS patients argues in favor of optic nerve imaging in future OCT MS studies, in order to achieve a better understanding of retinal axonal loss in non-ON eyes.

Contribution of Cortical Lesions to Cognitive Dysfunction in the PPMS Population: Comparison of Double Inversion Recovery (DIR) and Phase Sensitive Inversion Recovery (PSIR) Sequences Using a 3 Tesla MRI. (P6.144)

Contribution of Cortical Lesions to Cognitive Dysfunction in the PPMS Population: Comparison of Double Inversion Recovery (DIR) and Phase Sensitive Inversion Recovery (PSIR) Sequences Using a 3 Tesla MRI. (P6.144)

Cortical Ischemic Lesion Burden Measured by DIR Is Related to Carotid Artery Disease Severity

Background: Over time, exposure to cerebrovascular risk factors and carotid artery disease may cause multiple asymptomatic brain cortical and subcortical microinfarcts, which are commonly found at brain autopsy. So far, lack of convenient neuroimaging tools limited the investigation of grey matter ischemic damage in vivo. We applied the Double Inversion Recovery (DIR) sequence to explore the impact of carotid artery disease on intracortical ischemic lesion load in vivo, taking into account the impact of demographic characteristics and vascular risk factors. Methods: DIR was acquired in 62 patients with common cerebrovascular risk factors stratified in three groups according to carotid artery disease severity. Intracortical lesions scored on DIR (DIRlns) were classified by vascular territory, lobe and hemisphere. White matter hyperintensities (WMHs) volume was also quantified on Fluid Attenuated Inversion Recovery sequence (FLAIR). Results: Among demographic characteristics and cerebrovascular risk variables explored, General Linear Model indicated that age and carotid artery disease were significantly associated to DIRlns. After correcting for age, DIRlns load was found to be significantly dependent on carotid artery stenosis severity (F(2, 58) = 5.56, p = 0.006). A linear positive correlation between DIRlns and WMHs was found after correcting for age (p = 0.003). Conclusions: Carotid disease severity is associated with DIRlns accrual. Microembolism and impaired cerebral hemodynamics may act as physiopathological mechanisms underlying cortical ischemic damage. The role of other factors, such as small vessel disease and the possible interaction with carotid disease, remains to be further explored.

Double inversion recovery MR sequence for the detection of subacute subarachnoid hemorrhage.

The diagnosis of subacute subarachnoid hemorrhage is important because rebleeding may occur with subsequent life-threatening hemorrhage. Our aim was to determine the sensitivity of the 3D double inversion recovery sequence compared with CT, 2D and 3D FLAIR, 2D T2*, and 3D SWI sequences for the detection of subacute SAH. This prospective study included 25 patients with a CT-proved acute SAH. Brain imaging was repeated between days 14 and 16 (mean, 14.75 days) after clinical onset and included MR imaging (2D and 3D FLAIR, 2D T2*, SWI, and 3D double inversion recovery) after CT (median delay, 3 hours; range, 2-5 hours). A control group of 20 healthy volunteers was used for comparison. MR images and CT scans were analyzed independently in a randomized order by 3 blinded readers. For each subject, the presence or absence of hemorrhage was assessed in 4 subarachnoid areas (basal cisterns, Sylvian fissures, interhemispheric fissure, and convexity) and in brain ventricles. The diagnosis of subacute SAH was defined by the presence of at least 1 subarachnoid area with hemorrhage. For the diagnosis of subacute SAH, the double inversion recovery sequence had a higher sensitivity compared with CT (P < .001), 2D FLAIR (P = .005), T2* (P = .02), SWI, and 3D FLAIR (P = .03) sequences. Hemorrhage was present for all patients in the interhemispheric fissure on double inversion recovery images, while no signal abnormality was noted in healthy volunteers. Interobserver agreement was excellent with double inversion recovery. Our study showed that the double inversion recovery sequence has a higher sensitivity for the detection of subacute SAH than CT, 2D or 3D FLAIR, 2D T2*, and SWI.

Double inversion recovery sequence of the cervical spinal cord in multiple sclerosis and related inflammatory diseases.

MR imaging plays an important role in diagnosing MS and other related inflammatory diseases; however, imaging of the spinal cord is still challenging. We hypothesized that a 3D double inversion recovery sequence for cervical spinal cord imaging would be more sensitive in detecting inflammatory lesions than a conventional 2D T2-weighted TSE sequence at 3T. On a 3T MR imaging scanner, we examined 30 patients with suspected or established MS (MS, n = 16; clinically isolated syndrome, n = 12; isolated myelitis, n = 2) and 10 healthy controls. Newly developed 3D double inversion recovery and conventional 2D axial and sagittal T2-weighted TSE images of the cervical spinal cord were acquired. Two blinded neuroradiologists independently assessed the scans in pseudorandomized order for lesion numbers and rated lesion visibility and overall image quality on 5-point scales. A subsequent consensus reading delivered definite lesion counts. Standardized contrast-to-noise ratios were calculated in representative lesions of each patient. Overall, 28% more lesions could be detected with 3D double inversion recovery than with conventional T2WI (119 versus 93, P < .002). On average, the standardized contrast-to-noise ratio was significantly higher (P < .001) in double inversion recovery than in T2WI. Lesion visibility was rated significantly higher (P < .001) in double inversion recovery compared with T2WI despite lower image quality. The novel 3D double inversion recovery sequence allowed better detection of lesions in MS and related inflammatory diseases of the cervical spinal cord, compared with conventional 2D T2WI.

Added value of double inversion recovery magnetic resonance sequence in detection of cortical and white matter brain lesions in multiple sclerosis

ObjectiveThe aim of this study was to evaluate the value of double inversion recovery (DIR) magnetic resonance (MR) sequence in the detection of brain cortical and white matter lesions in multiple sclerosis (MS). Patients and methodsFifteen patients with remitting relapsing MS were included in this study. Imaging was performed on a 1.T MR system using DIR, fluid-attenuated inversion-recovery (FLAIR), and T2-weighted image (T2WI) sequences. The sensitivity of DIR was compared with the corresponding sensitivity of FLAIR and T2WI sequences. The contrast between lesions and normal-appearing gray matter (NAGM), normal-appearing white matter (NAWM), and cerebrospinal fluid (CSF) was determined for all sequences. ResultsDIR showed significantly more MS lesion load overall when compared to T2WI or FLAIR. Significantly higher number of lesions was seen in the supra- and infratentorial locations. DIR detected higher periventricular white matter lesions when compared to FLAIR, but did not detect significantly higher lesions when compared to T2WI. Significantly higher deep white matter, juxtacortical, and intracortical lesions were seen on DIR when compared to both T2WI and FLAIR. The image contrast measurements between the MS lesions and the NAWM in all anatomical locations were significantly higher in DIR sequence compared to both T2WI and FLAIR sequences. However, there was no significant statistical difference between the DIR and both T2WI and FLAIR sequences regarding the contrast of intracortical lesions compared to NAGM. ConclusionDIR sequence is valuable in the imaging workup of MS as it can detect more MS lesions compared to the T2W and FLAIR sequences in all anatomical locations. DIR showed better delineation between the white matter, gray matter, and the MS lesions due to its high image contrast. DIR sequence should be included in the routine MR protocol of MS patients especially to answer the question about intra-cortical and juxta-cortical MS lesions.

MRI characteristics of periaqueductal lesions in multiple sclerosis

BackgroundIn multiple sclerosis (MS), periaqueductal lesions (PAL) have been described histopathologically. ObjectivesWe sought to investigate the frequency and characteristics of PAL on magnetic resonance images (MRIs) in patients with MS or clinically isolated syndrome (CIS). MethodsWe analyzed proton density (PD)-weighted MRIs of 247 MS and 10 CIS patients. PAL were identified based on their abnormal hyperintensity and lesion shape on at least two consecutive slices. Patients with and without PAL were compared for clinical characteristics in a propensity score weighted analysis. ResultsWe identified PAL in 48/257 patients (18.7%), 34 of which had CIS or relapsing-remitting MS and 14 a progressive disease course. The shape of PAL was often circular (65%), or/and wedge-like (42%). Multi-planar image analysis in a subgroup of patients with double inversion recovery sequences revealed that 36% of PAL were periventricular lesions of the third ventricle extending towards the aqueduct. We found an association of PAL and brainstem functional system. ConclusionsAlthough PAL may be underreported in MS, they are relatively frequent and found at all clinical stages and in CIS. They could be considered as a variant of periventricular lesions in the supratentorial midbrain and thus be useful in the diagnosis of MS.

Double inversion recovery MR imaging of the breast: Efficacy in detection of breast cancer

To investigate the efficacy of the double inversion recovery sequence (DIR) in breast cancer detection. Fifty-six patients with biopsy-proven breast cancers underwent preoperative breast MRI, including sagittal DIR and contrast-enhanced T1-weighted images (CE-T1WI). Twenty-four of the 56 patients additionally underwent sagittal T1WI and T2WI. The signal intensities of the lesion (L) and ipsilateral normal breast tissue (N) were measured. The lesion-to-normal ratio (LNR) was defined as LNR = 100(L-N)/N. We compared LNRs among the four sequences, and then assessed the differences of LNRs between CE-T1WI and DIR in each pathologic subgroup (IDC and non-IDC group). Multiple regression analysis was performed to identify predictors of the signal-to-noise ratios (SNR) of the normal tissue or lesion and LNRs. The mean LNR did not differ significantly between DIR (58.65 ± 71.55) and CE-T1WI (59.78 ±31.04), nor did the LNRs between DIR and CE-T1WI in the two subgroups. The LNRs of DIR did not differ significantly between the two subgroups (P = 0.247). The SNR of lesions in DIR was correlated with the intraductal component percentage (r(2) = 0.485, P = 0.037). DIR and CE-T1WI showed similar tumor detection efficacy, and DIR could complement dynamic MRI for detecting breast cancer without a contrast agent.

흑혈류영상 획득 시 신호소실을 활용한 고속스핀에코기법의 유용성

본 연구는 흑혈류영상 획득에서 고속스핀에코기법의 신호소실 현상을 이용하여 검사시간을 최소화시켜 환자의 불편을 줄이고 진단적 가치를 유지하고자 하였다. 연구방법은 흑혈류영상을 획득한 환자 32명을 대상으로, 기존의 이중역전회복기법과 새로운 기법인 고속스핀에코기법을 각각 적용한 후, 기법에 따른 혈류의 신호소거 차이를 알아보기 위해 T1, T2 강조영상에서 내경동맥 내강의 SNR과 CNR을 비교 평가하였다. 연구결과, SNR은 고속스핀에코기법이 이중역전회복기법 보다 T1, T2 강조영상에서 11.49%(4.73), 13.66%(6.03) 낮았으며, CNR은 고속스핀에코기법이 T1 강조영상에서 8.69%(15.04) 높았고, T2 강조영상에서 7.55% (13.17) 낮았으나, 통계적 수준에서 두 기법간의 SNR과 CNR의 차이는 유의하지 않았다. 그러므로 흑혈류영상 획득 시 고속스핀에코기법을 이용한다면 진단적 가치는 유지하면서 검사시간을 최소화하여 환자의 불편을 줄일 수 있다고 판단된다. The purpose of our study is to shorten the scanning time and minimize the inconveniences of the patients in acquisition of the black blood images using the signal void effect in the fast spin echo technique while keeping the diagnostic value of the test. Thirty-two consecutive patients who underwent black blood MR imaging were examed with additional double inversion recovery (DIR) sequence and the conventional fast spin echo (FSE) sequence. Signal to Noise Ratio (SNR) and Contrast to Noise Ratio (CNR) of the internal carotid arteries' lumen were compared in T1 and T2 weighted images to determine whether there are differences between the two techniques for depiction of the signal void effect inside the vessel wall. The FSE images showed lower SNR values than the DIR images in both of the T1 and T2 weighted images (11.49% and 13.66% respectively). While the CNR values were higher in the FSE images than in the DIR images in both of the T1 and T2 weighted images (8.69% and 7.55% respectively).There was no significant difference between the two techniques for either of the SNR or CNR (p>0.05, p>0.05 respectively). The DIR and the FSE images demonstrated almost identical imaging patterns. Therefore, it is anticipated that the use of FSE technique in acquisition of the black blood imaging could reduce the inconveniences of the patients during the scanning and minimize exam time while keeping the diagnostic value of the test.

Pre- and post-contrast three-dimensional double inversion-recovery MRI in human glioblastoma

Fluid attenuated inversion recovery (FLAIR) MRI sequences have become an indispensible tool for defining the malignant boundary in patients with brain tumors by nulling the signal contribution from cerebrospinal fluid allowing both regions of edema and regions of non-enhancing, infiltrating tumor to become hyperintense on resulting images. In the current study we examined the utility of a three-dimensional double inversion recovery (DIR) sequence that additionally nulls the MR signal associated with white matter, implemented either pre-contrast or post-contrast, in order to determine whether this sequence allows for better differentiation between tumor and normal brain tissue. T1- and T2-weighted, FLAIR, dynamic susceptibility contrast (DSC)-MRI estimates of cerebral blood volume (rCBV), contrast-enhanced T1-weighted images (T1+C), and DIR data (pre- or post-contrast) were acquired in 22 patients with glioblastoma. Contrast-to-noise (CNR) and tumor volumes were compared between DIR and FLAIR sequences. Line profiles across regions of tumor were generated to evaluate similarities between image contrasts. Additionally, voxel-wise associations between DIR and other sequences were examined. Results suggested post-contrast DIR images were hyperintense (bright) in regions spatially similar those having FLAIR hyperintensity and hypointense (dark) in regions with contrast-enhancement or elevated rCBV due to the high sensitivity of 3D turbo spin echo sequences to susceptibility differences between different tissues. DIR tumor volumes were statistically smaller than tumor volumes as defined by FLAIR (Paired t test, P = 0.0084), averaging a difference of approximately 14 mL or 24 %. DIR images had approximately 1.5× higher lesion CNR compared with FLAIR images (Paired t test, P = 0.0048). Line profiles across tumor regions and scatter plots of voxel-wise coherence between different contrasts confirmed a positive correlation between DIR and FLAIR signal intensity and a negative correlation between DIR and both post-contrast T1-weighted image signal intensity and rCBV. Additional discrepancies between FLAIR and DIR abnormal regions were also observed, together suggesting DIR may provide additional information beyond that of FLAIR.

Comparison of Double Inversion Recovery and Conventional Magnetic Resonance Brain Imaging in Patients with Multiple Sclerosis and Relations with Disease Disability

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system, predominantly affecting the white matter, but also the grey matter. Aim of this study was to detect MS lesions with double inversion recovery (DIR), fluid-attenuated inversion recovery (FLAIR) and T2-weighted magnetic resonance (MR) techniques and determine the sensitivity of these techniques, and the correlation between the number of lesions and expanded disability state scale (EDSS) scores. Thirty-four patients with MS (20 females and 14 males) were included in this study. DIR and conventional MR (T2-A, FLAIR) sequences were obtained. Lesions were counted and classified as belonging to one of seven anatomical regions: cortical, juxtacortical, deep grey matter, deep white matter, mixed white matter-grey matter, periventricular white matter and infratentorial. The correlation between lesion number and EDSS scores was investigated. DIR images showed more intracortical and mixed white matter-grey matter lesions in comparison with both FLAIR and T2 sequences (p=0, p=0 respectively). There was a significant difference between mean lesion numbers at the juxtacortical region, obtained with DIR and T2-weighted images (p = 0.002). The total number of lesions obtained with all methods was similar. DIR brain imaging had the highest sensitivity in the detection of cortical and mixed white matter - grey matter lesions, compared with FLAIR and T2 sequences. In addition, the lesions obtained with DIR images were more easily visualized.

Contribution of cortical and white matter lesions to cognitive impairment in multiple sclerosis

Background: Cortical lesions (CLs) have been reported to be a better predictor for cognitive impairment than white matter (WM) lesions in relapsing–remitting multiple sclerosis (RRMS). Objectives: The objectives of this article are to investigate the contribution of CLs and WM lesions to cognitive impairment in 91 patients with MS and clinically isolated syndrome, and to test potential associations of CLs and WM lesions with fatigue and depression. Methods: Lesions were scored and segmented on 3D double inversion recovery sequences, according to their location (cortical, WM). Normalised grey matter volume was also determined. Cognitive performance was assessed with the SDMT and PASAT-3, fatigue with the FSMC and depression with the German version of the CES-D. Results: CL volume did not correlate with fatigue or depression, but correlated significantly with both neuropsychological outcome measures: PASAT-3 (r = −0.275, p = 0.009) and SDMT (r = −0.377, p < 0.001). Multiple regression analyses with age, WM lesions, CLs and GM volume as independent variables, however, did not reveal CL volume as a significant predictor of neuropsychological outcomes, whereas WM lesion volume significantly predicted SDMT and by trend PASAT performance. Conclusions: These findings suggest a role of WM lesions in the development of cognitive deficits, especially information-processing speed, which may be higher than previously assumed. Abbreviations: CES-D: Center for Epidemiologic Studies Depression scale (ADS-L: Allgemeine Depressions Skala-L, German version of CES-D), CIS: clinically isolated syndrome, CL: cortical lesion, DIR: double inversion recovery, EDSS: Expanded Disability Status Scale, FSMC: fatigue scale for motor and cognitive functions, GM: grey matter, MRI: magnetic resonance imaging, MS: multiple sclerosis, PASAT-3: paced auditory serial addition test 3s, PPMS: primary progressive multiple sclerosis, RRMS: relapsing–remitting multiple sclerosis, SDMT: symbol digit modalities test, SPM: statistical parametric mapping, SPMS: secondary progressive multiple sclerosis, WM: white matter

No MRI evidence of cortical lesions in neuromyelitis optica

Neuromyelitis optica (NMO) is a severe inflammatory demyelinating disease of the CNS in which a pathogenic role of anti-aquaporin-4 (AQP4) antibodies has been suggested. Although AQP4 is expressed in human cortex, recent histologic studies have failed to find any evidence of cortical demyelination in NMO. To evaluate, in vivo, the occurrence of focal and diffuse cortical pathology in NMO. We studied 30 patients with NMO, 30 patients with relapsing-remitting multiple sclerosis (RRMS), and 30 normal controls (NC). RRMS and NC were age- and gender-matched to NMO. The presence of cortical lesions (CLs) was evaluated on double inversion recovery sequence and cortical thickness (CTh) by the application of Freesurfer on 3 volumetric fast field echo T1-weighted images. No CL was observed in NC or in NMO, while 83 CLs were identified in 20/30 (66.7%) patients with RRMS. Although NMO did not differ from NC in the global CTh, a mild thinning was observed in some cortical areas (postcentral [p = 0.018], precentral [p = 0.009], and calcarine [p = 0.015] gyri) and in the thalamus (p = 0.036). Global and regional cortical thickness was significantly decreased in RRMS compared to both NMO and NC. Our in vivo data further suggest that the immune-mediated pathologic process occurring in NMO spares most of the cortex. NMO differs from multiple sclerosis, where CLs and atrophy are frequently found, even in early disease phases. Thus, MRI analysis of the cortex may be a potential diagnostic tool, especially in ambiguous cases.

Multiple Sclerosis Lesions and Irreversible Brain Tissue Damage

In current clinical practice, T2-weighted magnetic resonance imaging (MRI) is commonly applied to quantify the accumulated multiple sclerosis (MS)lesion load, whereas T1-weighted sequences are used to differentiate edema, blood-brain barrier breakdown by contrast enhancement, and irreversible brain tissue damage(commonly called “black holes” owing to the loss of signal intensity in T1-weighted sequences). Black holes are histopathologically associated with axonal loss and severe tissue destruction. In addition, double inversion recovery techniques were developed to improve the sensitivity to cortical lesions. To demonstrate the potential of ultrahigh-field 3-dimensional T1-weighted imaging using magnetization-prepared rapid acquisition and multiple gradient echoes(MPRAGE) to detect and characterize white and gray matter pathology in MS. Comparative study. The patients with MS were recruited from the outpatient clinics of the Neuro Cure Clinical Research Center and underwent 7-T brain MRI at the Berlin Ultrahigh Field Facility, both of which are in Berlin, Germany. Twenty patients with relapsing-remitting MS and 14 healthy controls underwent 7-T brain MRI, using a 24-channel receive head coil, and a subgroup of 18 patients with relapsing-remitting MS also underwent 1.5-T brain MRI. The imaging protocol included 2-dimensional T2-weighted fast low-angle shot (FLASH) and turbo inversion recovery magnitude (TIRM) sequences. For 3-dimensional T1-weighted imaging, the MPRAGE sequence was used. Each sequence was initially examined independently in separate analyses by an investigator blinded to all other data. In a second study, all detected lesions were retrospectively analyzed in a side-by-side comparison of all sequences. By use of 7-T T2-weighted FLASH imaging, 604 cerebral lesions were detected in the patients with relapsing-remitting MS (mean, 30.2 lesions per patient[range, 2-107 lesions per patient]), but none were detected in healthy controls. Cortical pathology was visible in 10 patients (6 cortical lesions and 37 leukocortical lesions). Within the 7-T acquisitions, each lesion detected at T2-weighted sequences and/or double inversion recovery sequences was also clearly delineated on corresponding MPRAGE sequences in side-by-side analysis.However, at 1.5 T, the MPRAGE images depicted only 452 of 561 lesions visualized in T2-weighted sequences and/or double inversion recovery sequences. In contrast,when analyzing each sequence separately, we found that the 7-T MPRAGE depicted more lesions than the 7-TFLASH (728 lesions vs 584 lesions), and almost twice as many as the 1.5-T MPRAGE (399 lesions). The 7-TMPRAGE also improved the detection of cortical and leukocortical lesions (15 lesions vs 58 lesions). At ultrahigh-field strength, T1-weighted MPRAGE is highly sensitive in detecting MS plaques within the white and the gray brain parenchyma. Our results indicate structural damage beyond demyelination in every lesion depicted, which is in accordance with postmortem histopathological studies. The 7-T MPRAGE clearly delineated every cortical lesion that was visualized by any other MRI sequence at 1.5 or 7 T.

Cerebellar Grey-Matter Lesion Load Is Related to Worse Motor Performance in Multiple Sclerosis Patients (P03.067)

Objective: To evaluate the relationships between cerebellar cortical lesions, motor performance and clinical parameters in multiple sclerosis (MS) patients. Background Grey matter pathology in MS correlates better with clinical measures than do white matter lesion load, but visualization of cortical lesions with conventional MRI remains unsatisfactory. Double inversion recovery (DIR) sequences have allowed a better detection of such lesions, but there is scarce information on the interaction of cerebellar cortical lesions and clinical disability. Design/Methods: We prospectively studied 21 relapsing remitting MS patients. They underwent clinical evaluation comprising EDSS and MSFC, and MRI in a 3T scanner (Philips, Achieva), including FLAIR and DIR sequences. Cerebellar cortical (CL) and mixed white matter-grey matter lesions (ML) were segmented using a semiautomatic thresholding technique on DIR sequences. Results: We included 15 female and 6 male RRMS patients with mean age 30.4 years (21 – 44), 7.5 years of disease duration (0 – 20), and 2.3 of EDSS (1 – 3.5). Mean number of ML was 0.6 (0-4) with mean volume of 47.4 mm3 (0-303.3). Mean number of CL was 0.8 (0-4) with mean volume of 53.8 mm3 (0-198.5). The 9HPT time was related to cerebellar CL number and volume (R=0.52, p=0.01, and R=0.48, p=0.02, respectively). Similarly T25FW was related to CL number and volume (R=0.58, p Conclusions: Cerebellar grey-matter lesion load may significantly contribute to worse arm and leg function in MS patients, and may be increased in female patients. Supported by: Institutional grant from Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) # 2010/00885-4. Disclosure: Dr. Damasceno has nothing to disclose. Dr. Damasceno has nothing to disclose. Dr. Cendes has nothing to disclose.