Phase-sensitive Inversion Recovery Research Articles

Phase-Sensitive Inversion-Recovery MRI Improves Longitudinal Cortical Lesion Detection in Progressive MS.

Previous studies comparing phase sensitive inversion recovery (PSIR) to double inversion recovery (DIR) have demonstrated that use of PSIR improves cross-sectional in vivo detection of cortical lesions (CL) in multiple sclerosis. We studied the utility of PSIR in detection/characterization of accrual of CL over time in a 1-year longitudinal study in primary progressive multiple sclerosis (PPMS) compared to DIR. PSIR and DIR images were acquired with 3T magnetic resonance imaging (MRI) in 25 patients with PPMS and 19 healthy controls at baseline, and after 1 year in 20 patients with PPMS. CL were classified as intracortical, leucocortical or juxtacortical. Lesion counts and volumes were calculated for both time points from both sequences and compared. Correlations with measures of physical and cognitive disability were determined as well as new CL counts and volumes. Compared to DIR, PSIR led to detection of a higher number of CL involving a larger proportion of patients with PPMS both cross-sectionally (p = 0.006, 88%) and longitudinally (p = 0.007, 95%), and led to the reclassification of a third of CL seen on DIR at each time point. Interestingly, PSIR was more sensitive to new CL accumulation over time compared to DIR. PSIR is a promising technique to monitor cortical damage and disease progression in patients with PPMS over a short-term follow-up.

Whole heart free breathing phase sensitive inversion recovery MRI integrated with iterative self navigation for 100% scan efficiency; a first patient study

Background Phase Sensitive Inversion Recovery (PSIR) [1] allows for the visualization of myocardial scars using late gadolinium enhancement (LGE), ensuring robustness with respect to sequence timing. 3D whole-heart PSIR has been integrated with diaphragmatic navigator-gating (NAV) [2] to compensate for respiratory motion. However, both NAV and the need for two different datasets to be acquired (IR and reference) lead to a prohibitively long scanning time. Thus, integrating 1D respiratory Self-Navigation (SN) [3] with 3D-PSIR to obtain 100% scan efficiency is desirable. Unfortunately, signal and contrast variations between the IR and the reference dataset pose a major challenge. Here, we hypothesized that a recently introduced contrast independent iterative approach to 1D SN (IT-SN) [4] effectively suppresses respiratory motion in 3D-PSIR acquisitions.

An Examination for Uterine Dynamic Study with Phase-sensitive Inversion-recovery

The depth of myometrial invasion in patients with endometrial carcinoma is recognized as an important factor that closely correlates with prognosis. Preoperative assessment of myometrial invasion is essential for planning surgery. To enhance the contrast between myometrium and endometrium including myometrial invasion with endometrial carcinoma, we optimized the sequence parameter with phase-sensitive inversion-recovery (PSIR) in gadolinium dynamic study of uterine corpus. On a 1.5-T magnetic resonance imaging (MRI), images were acquired by three-dimensional (3D) T1 -turbo field echo (TFE) with PSIR sequence and gadolinium-diethylenetriamine pentaacetic acid( Gd-DTPA) diluted phantom (0-5 mmol/L) and myometrium model (manganese chloride tetrahydrate+agar). We calculated the null point and the contrast-to-noise ratio (CNR) at multiple TFE inversion delay times, 200 ms-maximum in each combination; flip angles (FAs), 5-35 degrees; TFE factor, 20-40; and shot interval (SI), 500-1000 ms. We assumed that dynamic scanning time was 30 seconds when the sensitivity encoding factor was 2, namely, in this study, the scanning time was 1 minute with no sensitivity encoding. In addition, we compared CNR between optimized PSIR sequence ande-Thrive. We recognized a successful CNR of the 3D PSIR parameter was TFE inversion delay times, 335 ms; FA, 25 degrees; TFE factor, 20; and SI, 500 ms. In each gadolinium-DTPA diluted phantom, the average CNR of the optimized PSIR sequence was approximately 1.7 times (maximum: 3 times) higher than e-Thrive. Optimizing sequence parameter of PSIR is applicable in gadolinium dynamic study of uterine corpus.

New automatic algorithm for segmentation of myocardial scar in both inversion recovery and phase sensitive inversion recovery late gadolinium enhancement: validation against TTC and in multi-center, multi-vendor patient data

New automatic algorithm for segmentation of myocardial scar in both inversion recovery and phase sensitive inversion recovery late gadolinium enhancement: validation against TTC and in multi-center, multi-vendor patient data Jane Tufvesson, Robert Jablonowski, Henrik Engblom, Marcus Carlsson, Anthony H Aletras, Pavel Hoffmann, Alexis Jacquier, Frank Kober, Bernhard Metzler, David Erlinge, Dan Atar, Hakan Arheden, Einar Heiberg

A novel calibration technique to obtain high resolution 3D T1 Maps for Infarct characterization

Background Myocardial T1 mapping enables quantification of extracellular volume fraction (ECV), which correlates with myocardial fibrosis and is predictive of adverse cardiac events. Quantitative T1 mapping is highly useful in detecting scar tissue in patients with prior myocardial infarctions or those with other cardiomyopathies. The Modified Look-Locker inversion recovery (MOLLI) sequence is a clinical standard for T1 mapping, however it is limited by low spatial resolution which prevents it from being used for infarct characterization. In this study, a novel technique to convert high resolution 3D phase sensitive inversion recovery (3D-PSIR) images into high resolution T1 maps by calibration with lowresolution MOLLI T1 maps. Methods From a phantom study using 11 agarose vials doped with different concentrations of Ni, an exponential relationship was derived between signal intensity and T1 using a 3D-PSIR segmented Turbo FLASH and MOLLI acquisition, respectively. 9 canines with chronic infarcts (ranging from 12-14 weeks) were scanned on a 1.5 T Siemens Avanto scanner. A 3D-PSIR (covering the entire left ventricle) and a single long axis MOLLI were collected prior to contrast injection and 15-20 minutes after contrast injection (Gd-DTPA). The MOLLI and 3D-PSIR images had resolutions of approximately isotropic in-plane 1.3-1.4 mm × 8.0 mm and 1.4 × 1.4 × 1.4 mm, respectively. Six regions of interest (3 in the myocardium, 2 in the blood pool, and 1 in the liver) were drawn in the MOLLI image

A clinical combined gadobutrol bolus and slow infusion protocol enabling angiography, inversion recovery whole heart, and late gadolinium enhancement imaging in a single study.

BackgroundThe use of gadolinium contrast agents in cardiovascular magnetic resonance is well-established and serves to improve both vascular imaging as well as enable late gadolinium enhancement (LGE) imaging for tissue characterization. Currently, gadofosveset trisodium, an intravascular contrast agent, combined with a three-dimensional inversion recovery balanced steady state free precession (3D IR bSSFP) sequence, is commonly used in pediatric cardiac imaging and yields excellent vascular imaging, but cannot be used for late gadolinium enhancement. Gadofosveset use remains limited in clinical practice, and manufacture was recently halted, thus an alternative is needed to allow 3D IR bSSFP and LGE in the same study.MethodsHere we propose a protocol to give a bolus of 0.1 mL/kg = 0.1 mmol/kg gadobutrol (GADAVIST/GADOVIST) for time-resolved magnetic resonance angiography (MRA). Subsequently, 0.1 mmol/kg is diluted up to 5 or 7.5 mL with saline and then loaded into intravenous tubing connected to the patient. A 0.5 mL short bolus is infused, then a slow infusion is given at 0.02 or 0.03 mL/s. Image navigated (iNAV) 3D IR bSSFP imaging is initiated 45–60 s after the initiation of the infusion, with a total image acquisition time of ~5 min. If necessary, LGE imaging using phase sensitive inversion recovery reconstruction (PSIR) is performed at 10 min after the infusion is initiated.ResultsWe have successfully performed the above protocol with good image quality on 10 patients with both time-resolved MRA and 3D IR bSSFP iNAV imaging. Our initial attempts to use pencil beam respiratory navigation failed due to signal labeling in the liver by the navigator. We have also performed 2D PSIR LGE successfully, with both LGE positive and LGE negative results.ConclusionA bolus of gadobutrol, followed later by a slow infusion, allows time-resolved MRA, 3D IR bSSFP using the iNAV navigation technique, and LGE imaging, all in a single study with a single contrast agent.

Dark blood late enhancement imaging

BackgroundBright blood late gadolinium enhancement (LGE) imaging typically achieves excellent contrast between infarcted and normal myocardium. However, the contrast between the myocardial infarction (MI) and the blood pool is frequently suboptimal. A large fraction of infarctions caused by coronary artery disease are sub-endocardial and thus adjacent to the blood pool. It is not infrequent that sub-endocardial MIs are difficult to detect or clearly delineate.MethodsIn this present work, an inversion recovery (IR) T2 preparation was combined with single shot steady state free precession imaging and respiratory motion corrected averaging to achieve dark blood LGE images with good signal to noise ratio while maintaining the desired spatial and temporal resolution. In this manner, imaging was conducted free-breathing, which has benefits for image quality, patient comfort, and clinical workflow in both adults and children. Furthermore, by using a phase sensitive inversion recovery reconstruction the blood signal may be made darker than the myocardium (i.e., negative signal values) thereby providing contrast between the blood and both the MI and remote myocardium. In the proposed approach, a single T1-map scout was used to measure the myocardial and blood T1 using a MOdified Look-Locker Inversion recovery (MOLLI) protocol and all protocol parameters were automatically calculated from these values within the sequence thereby simplifying the user interface.ResultsThe contrast to noise ratio (CNR) between MI and remote myocardium was measured in n = 30 subjects with subendocardial MI using both bright blood and dark blood protocols. The CNR for the dark blood protocol had a 13 % loss compared to the bright blood protocol. The CNR between the MI and blood pool was positive for all dark blood cases, and was negative in 63 % of the bright blood cases. The conspicuity of subendocardial fibrosis and MI was greatly improved by dark blood (DB) PSIR as well as the delineation of the subendocardial border.ConclusionsFree-breathing, dark blood PSIR LGE imaging was demonstrated to improve the visualization of subendocardial MI and fibrosis in cases with low contrast with adjacent blood pool. The proposed method also improves visualization of thin walled fibrous structures such as atrial walls and valves, as well as papillary muscles.

Revised Recommendations of the Consortium of MS Centers Task Force for a Standardized MRI Protocol and Clinical Guidelines for the Diagnosis and Follow-Up of Multiple Sclerosis.

An international group of neurologists and radiologists developed revised guidelines for standardized brain and spinal cord MR imaging for the diagnosis and follow-up of MS. A brain MR imaging with gadolinium is recommended for the diagnosis of MS. A spinal cord MR imaging is recommended if the brain MR imaging is nondiagnostic or if the presenting symptoms are at the level of the spinal cord. A follow-up brain MR imaging with gadolinium is recommended to demonstrate dissemination in time and ongoing clinically silent disease activity while on treatment, to evaluate unexpected clinical worsening, to re-assess the original diagnosis, and as a new baseline before starting or modifying therapy. A routine brain MR imaging should be considered every 6 months to 2 years for all patients with relapsing MS. The brain MR imaging protocol includes 3D T1-weighted, 3D T2-FLAIR, 3D T2-weighted, post-single-dose gadolinium-enhanced T1-weighted sequences, and a DWI sequence. The progressive multifocal leukoencephalopathy surveillance protocol includes FLAIR and DWI sequences only. The spinal cord MR imaging protocol includes sagittal T1-weighted and proton attenuation, STIR or phase-sensitive inversion recovery, axial T2- or T2*-weighted imaging through suspicious lesions, and, in some cases, postcontrast gadolinium-enhanced T1-weighted imaging. The clinical question being addressed should be provided in the requisition for the MR imaging. The radiology report should be descriptive, with results referenced to previous studies. MR imaging studies should be permanently retained and available. The current revision incorporates new clinical information and imaging techniques that have become more available.

Abstract 11574: Ventricular Arrhythmia Ablation Lesions in Children and Adolescents: Acute Magnetic Resonance Imaging With Outcome Correlation

Introduction: Catheter ablation for arrhythmias is not always 100% effective when using current techniques. Failure of ablation may be secondary to inadequate lesion development. Peri-procedural visualization of ablation lesions may identify inadequate lesions or gaps to guide further ablation and reduce risk of arrhythmia recurrence. Methods: This pilot feasibility study assessed acute post-procedure ablation lesions by MRI, and correlated these findings with clinical outcomes. Six patients who underwent ventricular tachycardia ablation were transferred immediately post-ablation to a 1.5T MRI scanner for imaging. Late gadolinium enhancement (LGE) imaging was performed using a novel motion-corrected, phase sensitive inversion recovery sequence while free breathing. Immediate and short term arrhythmia recurrences were assessed. Results: Patient characteristics include median age 14.5 yrs (11 - 17 yrs), median weight 59 kg (43 - 81kg), normal cardiac anatomy (n = 4), anomalous coronary artery post repair (n = 1), and cardiac rhabdomyomas (n = 1). All patients underwent radiofrequency catheter ablation of ventricular arrhythmia with acute procedural success. LGE was identified at the reported ablation site in 5/6 patients, and not seen in 1 patient. The 5 patients with identifiable lesions were arrhythmia- and symptom-free at follow-up, ranging 1-6 months. The 1 patient in whom a lesion could not be identified had recurrence of frequent premature ventricular contractions within 2 hours post-procedure, confirmed on Holter monitoring 1 month later. Conclusions: Ventricular ablation lesion visibility by MRI in the acute post-procedure setting is feasible, and lesions identifiable with MRI may correlate with clinical outcomes. MRI identification of gaps or inadequate lesions may provide the unique temporal opportunity for additional ablation therapy to decrease arrhythmia recurrence.

Imaging cardiac ATTR amyloid

The heart is the principal site of involvement in non-hereditary ATTR amyloidosis and a major driver of treatment options and prognosis in hereditary forms of the disease. The goals of cardiac imaging in amyloidosis are to aid diagnosis, provide prognostic information, track disease progression and evaluate response to therapy. Echocardiography has long been the mainstay of cardiac evaluation in amyloidosis, particularly that of diastolic dysfunction, but its precision is limited and both inter and intra-observer variability constrain its capacity to detect changes. The recent refinement of myocardial strain imaging provides more reproducible and more sensitive evaluation of systolic impairment, which may be overlooked in amyloidosis, and the longitudinal strain pattern of relative apical sparing strongly supports diagnosis of amyloidosis. Two investigations that are transforming our understanding of cardiac amyloidosis are bone scintigraphy and cardiovascular magnetic resonance (CMR). CMR with gadolinium contrast has proved to be invaluable for identification of cardiac amyloid, showing characteristic patterns of global subendocardial and transmural late gadolinium enhancement associated with abnormal myocardial and blood pool kinetics. The recent refinement of phase-sensitive inversion recovery sequence is highly sensitive and specific, producing findings that are virtually pathognomonic for amyloid. CMR is inferior to echocardiography for evaluating diastolic function but can assess the heart's structure and systolic function with greater accuracy and precision. A key advantage of CMR is its unique ability to give insight about tissue composition through myocardial tissue characterization. T1 mapping studies can quantify the massive expansion of the extracellular space caused by amyloid deposition as well as evaluating the myocyte response to it, i.e. associated hypertrophy or cell loss. The ability to independently track changes in amyloid load and myocardial cell mass will be invaluable in assessing new therapies. One significant limitation of CMR is its incompatibility with most implanted pacemakers and ICDs, an issue that may be addressed by the development of dynamic equilibrium CT, in which gated five minute contrast-enhanced scans have shown excellent potential for diagnosis and quantification of cardiac amyloid. It has been known for decades that bone scintigraphy tracers can localize to cardiac amyloid deposits, but the enormous potential of this tool has only been fully realized in recent years. Studies have confirmed that 99mTc-3, 3-diphosphono-1, 2-propanodicarboxylic acid (DPD) localizes to the heart in patients with cardiac ATTR amyloidosis with incredible sensitivity and high specificity. The mechanism remains unknown, but virtually all patients with clinically significant cardiac ATTR amyloidosis show Grade 2 or greater localization to the heart using the simple Perugini Grade 1-3 scoring system. Indeed, scans in apparently healthy individuals who have undergone predictive genetic testing for hereditary ATTR amyloidosis have shown that Grade 1 DPD uptake occurs before symptoms or abnormalities on echo or CMR have developed, reflecting the earliest evidence of cardiac ATTR amyloid. DPD scintigraphy is not completely specific for ATTR amyloid in that positive scans occur in a small proportion of patients with (usually very advanced) cardiac AL amyloidosis and some other very rare types, but Grade 2 or 3 cardiac uptake in the presence of a consistent echo and/or CMR and in the absence of a monoclonal gammopathy is in practice sufficient to make a non-invasive diagnosis of cardiac ATTR amyloidosis.

Circulation : Clinical Summaries

<i>Circulation</i> : Clinical Summaries

Prognostic Value of Late Gadolinium Enhancement Cardiovascular Magnetic Resonance in Cardiac Amyloidosis.

The prognosis and treatment of the 2 main types of cardiac amyloidosis, immunoglobulin light chain (AL) and transthyretin (ATTR) amyloidosis, are substantially influenced by cardiac involvement. Cardiovascular magnetic resonance with late gadolinium enhancement (LGE) is a reference standard for the diagnosis of cardiac amyloidosis, but its potential for stratifying risk is unknown. Two hundred fifty prospectively recruited subjects, 122 patients with ATTR amyloid, 9 asymptomatic mutation carriers, and 119 patients with AL amyloidosis, underwent LGE cardiovascular magnetic resonance. Subjects were followed up for a mean of 24±13 months. LGE was performed with phase-sensitive inversion recovery (PSIR) and without (magnitude only). These were compared with extracellular volume measured with T1 mapping. PSIR was superior to magnitude-only inversion recovery LGE because PSIR always nulled the tissue (blood or myocardium) with the longest T1 (least gadolinium). LGE was classified into 3 patterns: none, subendocardial, and transmural, which were associated with increasing amyloid burden as defined by extracellular volume (P<0.0001), with transitions from none to subendocardial LGE at an extracellular volume of 0.40 to 0.43 (AL) and 0.39 to 0.40 (ATTR) and to transmural at 0.48 to 0.55 (AL) and 0.47 to 0.59 (ATTR). Sixty-seven patients (27%) died. Transmural LGE predicted death (hazard ratio, 5.4; 95% confidence interval, 2.1-13.7; P<0.0001) and remained independent after adjustment for N-terminal pro-brain natriuretic peptide, ejection fraction, stroke volume index, E/E', and left ventricular mass index (hazard ratio, 4.1; 95% confidence interval, 1.3-13.1; P<0.05). There is a continuum of cardiac involvement in systemic AL and ATTR amyloidosis. Transmural LGE is determined reliably by PSIR and represents advanced cardiac amyloidosis. The PSIR technique provides incremental information on outcome even after adjustment for known prognostic factors.

Late gadolinium enhancement cardiac imaging on a 3T scanner with parallel RF transmission technique: prospective comparison of 3D-PSIR and 3D-IR

To qualitatively and quantitatively compare different late gadolinium enhancement (LGE) sequences acquired at 3T with a parallel RF transmission technique. One hundred and sixty participants prospectively enrolled underwent a 3T cardiac MRI with 3 different LGE sequences: 3D Phase-Sensitive Inversion-Recovery (3D-PSIR) acquired 5minutes after injection, 3D Inversion-Recovery (3D-IR) at 9minutes and 3D-PSIR at 13minutes. All LGE-positive patients were qualitatively evaluated both independently and blindly by two radiologists using a 4-level scale, and quantitatively assessed with measurement of contrast-to-noise ratio and LGE maximal surface. Statistical analyses were calculated under a Bayesian paradigm using MCMC methods. Fifty patients (70% men, 56yo ± 19) exhibited LGE (62% were post-ischemic, 30% related to cardiomyopathy and 8% post-myocarditis). Early and late 3D-PSIR were superior to 3D-IR sequences (global quality, estimated coefficient IR > early-PSIR : -2.37 CI = [-3.46 ; -1.38], prob(coef > 0) = 0% and late-PSIR > IR : 3.12 CI = [0.62 ; 4.41], prob(coef > 0) = 100%), LGE surface estimated coefficient IR > early-PSIR: -0.09 CI = [-1.11; -0.74], prob(coef > 0) = 0% and late-PSIR > IR : 0.96 CI = [0.77; 1.15], prob(coef > 0) = 100%). Probabilities for late PSIR being superior to early PSIR concerning global quality and CNR were over 90%, regardless of the aetiological subgroup. In 3T cardiac MRI acquired with parallel RF transmission technique, 3D-PSIR is qualitatively and quantitatively superior to 3D-IR. • Late gadolinium enhancement is an essential part of a cardiac MRI examination • PSIR and IR sequences are the two possible options for LGE imaging • At 3T with parallel RF transmission, PSIR sequences are significantly better • One LGE sequence is sufficient, allowing an optimization of the acquisition time.

A longitudinal study of cortical grey matter lesion subtypes in relapse-onset multiple sclerosis

BackgroundCortical grey matter (GM) lesions are common in multiple sclerosis (MS), but little is known about their temporal evolution. We investigated this in people with relapsing–remitting (RR) and secondary progressive...

Myocardial Late Gadolinium Enhancement: Accuracy of T1 Mapping-based Synthetic Inversion-Recovery Imaging.

To compare the accuracy of detection and quantification of myocardial late gadolinium enhancement (LGE) with a synthetic inversion-recovery (IR) approach with that of conventional IR techniques. This prospective study was approved by the institutional review board and compliant with HIPAA. All patients gave written informed consent. Between June and November 2014, 43 patients (25 men; mean age, 54 years ± 16) suspected of having previous myocardial infarction underwent magnetic resonance (MR) imaging, including contrast material-enhanced LGE imaging and T1 mapping. Synthetic magnitude and phase-sensitive IR images were generated on the basis of T1 maps. Images were assessed by two readers. Differences in the per-patient and per-segment LGE detection rates between the synthetic and conventional techniques were analyzed with the McNemar test, and the accuracy of LGE quantification was calculated with the paired t test and Bland-Altman statistics. Interreader agreement for the detection and quantification of LGE was analyzed with κ and Bland-Altman statistics, respectively. Seventeen of the 43 patients (39%) had LGE patterns consistent with myocardial infarction. The sensitivity and specificity of synthetic magnitude and phase-sensitive IR techniques in the detection of LGE were 90% and 95%, respectively, with patient-based analysis and 94% and 99%, respectively, with segment-based analysis. The area of LGE measured with synthetic IR techniques showed excellent agreement with that of conventional techniques (4.35 cm(2) ± 1.88 and 4.14 cm(2)± 1.62 for synthetic magnitude and phase-sensitive IR, respectively, compared with 4.25 cm(2) ± 1.92 and 4.22 cm(2) ± 1.86 for conventional magnitude and phase-sensitive IR, respectively; P > .05). Interreader agreement was excellent for the detection (κ > 0.81) and quantification (bias range, -0.34 to 0.40; P > .05) of LGE. The accuracy of the T1 map-based synthetic IR approach in the detection and quantification of myocardial LGE in patients with previous myocardial infarction was similar to that of conventional IR techniques. The use of T1 mapping to derive synthetic LGE images may reduce imaging times and operator dependence in future T1 mapping protocols with full left ventricular coverage.

MRI-detectable cortical lesions in the cerebellum and their clinical relevance in multiple sclerosis

Background: The demonstration of cortical lesions (CL) in the cerebellum by magnetic resonance imaging (MRI) is hampered by technical and anatomical constraints. Objective: To investigate the occurrence of cerebellar CL and their correlation with cerebellar-related disability by combining Double Inversion Recovery (DIR) and Phase Sensitive Inversion Recovery (PSIR) MRI images in multiple sclerosis (MS) patients. Material and methods: 40 MS patients (10 CIS/eRRMS, 24 RRMS, 6 SPMS), having a wide range of disability and disease duration, were enrolled. DIR and PSIR images were obtained with a 3T-MRI. Results: Cerebellar white matter lesions (WML) and/or CL were observed in 33/40 patients (82.5%) among which 14/40 had only CL. CL were demonstrated in 26/40 patients by DIR and in 31/40 by PSIR, and their number increased from CIS/eRRMS to SPMS. PSIR disclosed a significantly higher number of CL compared to DIR (RRMS: p=0.0008; SPMS: p=0.002). CL number correlates with the cerebellar Expanded Disability Status Score (EDSS) score (r=0.72, p<0.0001). No correlation was observed between supra-tentorial and cerebellar CL. Conclusions: CL are detected by PSIR in the cerebellum of the majority of MS patients, are more than WML, increase with disease progression and strongly correlate with the cerebellar EDSS. Thus, the observation of CL in the cerebellum of MS at clinical onset might be useful for prognostic and therapeutic aims.

The Parallel Analysis of Phase Sensitive Inversion Recovery (PSIR) and Double Inversion Recovery (DIR) Images Significantly Improves the Detection of Cortical Lesions in Multiple Sclerosis (MS) since Clinical Onset.

BackgroundDouble inversion recovery (DIR) detects only a minority (<20%) of cortical lesions (CL) in multiple sclerosis (MS). Phase-sensitive inversion recovery (PSIR) was suggested to be substantially superior to DIR in the detection of cortical lesions (CL). These two sequences might be complementary.ObjectivesTo analyze CL frequency and type in MS patients having different disease duration and disability, including patients at clinical onset, and to discern more correctly the artifacts, by combining DIR and PSIR images.Patients and Methods40 patients were enrolled in the study: 10 clinically isolated syndrome/early relapsing remitting MS (CIS/eRRMS), 24 relapsing remitting MS (RRMS), 6 secondary progressive MS (SPMS). DIR and PSIR images were jointly used to classify lesions as purely intracortical (IC), leukocortical (LC) and juxtacortical (JC).ResultsPSIR disclosed CL in 100% of the patients and was capable of identifying more than four times lesions (455.5%, p<0.00001), especially IC (mean numbers: 36.5 in CIS/eRRMS, 45.0 in RRMS and 52.3 in SPMS) and LC (mean numbers: 10.9 in CIS/eRRMS, 20.1 in RRMS and 25.3 in SPMS), compared to DIR (p<0.00001). CL number was significantly higher in SPMS compared to RRMS (p<0.0001). Artifacts were more accurately identified by comparing the two sequences.ConclusionsOur study confirms the higher ability of PSIR in disclosing and classifying CL. The presence of CL in all CIS patients further points out the relevance of cortical pathology in MS. Whether the parallel analysis of DIR and PSIR images may be useful for diagnostic purposes, especially when a diagnosis of MS is suspected but not confirmed by routine MRI, needs to be evaluated in larger patient series. The analysis of the cortex by DIR and PSIR may also allow a better stratification of the patients for prognostic and counseling purposes, as well as for their inclusion in clinical studies.

Characteristics of lesional and extra-lesional cortical grey matter in relapsing–remitting and secondary progressive multiple sclerosis: A magnetisation transfer and diffusion tensor imaging study

Background: In multiple sclerosis (MS), diffusion tensor and magnetisation transfer imaging are both abnormal in lesional and extra-lesional cortical grey matter, but differences between clinical subtypes and associations with clinical outcomes have only been partly assessed. Objective: To compare mean diffusivity, fractional anisotropy and magnetisation transfer ratio (MTR) in cortical grey matter lesions (detected using phase-sensitive inversion recovery (PSIR) imaging) and extra-lesional cortical grey matter, and assess associations with disability in relapse-onset MS. Methods: Seventy-two people with MS (46 relapsing–remitting (RR), 26 secondary progressive (SP)) and 36 healthy controls were included in this study. MTR, mean diffusivity and fractional anisotropy were measured in lesional and extra-lesional cortical grey matter. Results: Mean fractional anisotropy was higher and MTR lower in lesional compared with extra-lesional cortical grey matter. In extra-lesional cortical grey matter mean fractional anisotropy and MTR were lower, and mean diffusivity was higher in the MS group compared with controls. Mean MTR was lower and mean diffusivity was higher in lesional and extra-lesional cortical grey matter in SPMS when compared with RRMS. These differences were independent of disease duration. In multivariate analyses, MTR in extra-lesional more so than lesional cortical grey matter was associated with disability. Conclusion: Magnetic resonance abnormalities in lesional and extra-lesional cortical grey matter are greater in SPMS than RRMS. Changes in extra-lesional compared with lesional cortical grey matter are more consistently associated with disability.

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)

Age, Gender and Normalization Covariates for Spinal Cord Gray Matter and Total Cross-Sectional Areas at Cervical and Thoracic Levels: A 2D Phase Sensitive Inversion Recovery Imaging Study

The source of inter-subject variability and the influence of age and gender on morphometric characteristics of the spinal cord, such as the total cross-sectional area (TCA), the gray matter (GM) and white matter (WM) areas, currently remain under investigation. Understanding the effect of covariates such as age, gender, brain volumes, and skull- and vertebra-derived metrics on cervical and thoracic spinal cord TCA and GM areas in healthy subjects would be fundamental for exploring compartment specific changes in neurological diseases affecting the spinal cord. Using Magnetic Resonance Imaging at 3T we investigated 32 healthy subjects using a 2D phase sensitive inversion recovery sequence and we measured TCA, GM and WM areas at 4 cervical and thoracic levels of the spinal cord. We assessed age and gender relationships of cord measures and explored associations between cord measures and a) brain volumes and b) skull- and vertebra-derived metrics. Age and gender had a significant effect on TCA, WM and GM areas (with women and elderly having smaller values than men and younger people respectively), but not on the GM area/TCA ratio. The total intracranial volume and C3 vertebra dimensions showed the highest correlations with cord measures. When used in multi-regression models, they reduced cord areas group variability by approximately a third. Age and gender influences on cord measures and normalization strategies here presented might be of use in the study of compartment specific changes in various neurological diseases affecting the spinal cord.