scholarly journals MRI T2 Mapping of Knee Articular Cartilage Using Different Acquisition Sequences and Calculation Methods at 1.5 Tesla

2018 ◽  
Vol 27 (5) ◽  
pp. 443-450 ◽  
Author(s):  
Mokhtar Mars ◽  
Mouna Chelli ◽  
Zeineb Tbini ◽  
Fethi Ladeb ◽  
Souha Gharbi
Keyword(s):  
High Resolution ◽  
Spin Echo ◽  
T2 Mapping ◽  
Relaxation Times ◽  
T Test ◽  
Reference Sequence ◽  
Fast Spin Echo ◽  
Calculation Methods ◽  
Scanning Time ◽  
Significant Difference

Objective: This study aims to determine how magnetic resonance imaging (MRI) acquisition techniques and calculation methods affect T2 values of knee cartilage at 1.5 tesla and to identify sequences that can be used for high-resolution T2 mapping in short scanning times. Materials and Methods: This study was performed on phantom and 29 patients who underwent MRI of the knee joint at 1.5 tesla. The protocol includes T2 mapping sequences based on Single-Echo Spin Echo (SESE), Multi-Echo Spin Echo (MESE), Fast Spin Echo (FSE) and Turbo Gradient Spin Echo (TGSE). The T2 relaxation times were quantified and evaluated using three calculation methods (MapIt, Syngo Offline and mono-exponential fit). signal-to-noise ratios (SNR) were measured in all sequences. All statistical analyses were performed using the t-test. Results: The average T2 values in phantom were 41.7 ± 13.8 ms for SESE, 43.2 ± 14.4 ms for MESE, 42.4 ± 14.1 ms for FSE and 44 ± 14.5 ms for TGSE. In the patient study, the mean differences were 6.5 ± 8.2 ms, 7.8 ± 7.6 ms and 8.4 ± 14.2 ms for MESE, FSE and TGSE compared to SESE, respectively; these statistical results were not significantly different (p > 0.05). The comparison between the three calculation methods showed no significant difference (p > 0.05). The t-test showed no significant difference between SNR values for all sequences. Conclusion: T2 values depend not only on the sequence type but also on the calculation method. None of the sequences revealed significant differences compared to the SESE reference sequence. TGSE with its short scanning time can be used for high-resolution T2 mapping.

scholarly journals Myocardial Tissue Characterization By T2 Mapping in Thalassemia Major

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 27-28
Author(s):  
Alessia Pepe ◽  
Nicola Martini ◽  
Rita Borrello ◽  
Vincenzo Positano ◽  
Laura Pistoia ◽  
...  
Keyword(s):  
Tissue Characterization ◽  
Spin Echo ◽  
T2 Mapping ◽  
Relaxation Times ◽  
Thalassemia Major ◽  
Fast Spin Echo ◽  
Myocardial Inflammation ◽  
Healthy Population ◽  
Myocardial Iron ◽  
Magnetic Resonance Imaging Mri

Introduction.The presence of iron deposits results in a significant reduction in all magnetic resonance imaging (MRI) relaxation times (T1, T2 and T2*). In the clinical setting the T2* technique is the method of choice for cardiac iron quantification and it has revolutionized the management of patients with hemoglopinopathies. Purpose.To compare myocardial T2 against T2* in patients with thalassemia major (TM) for myocardial iron characterization. Methods.133 TM patients (79 females, 38.4±11.3 years) enrolled in the Extension Myocardial Iron Overload in Thalassemia (eMIOT) Network were considered. T2 and T2* images were acquired, respectively, with multi-echo fast-spin-echo and gradient-echo sequences. Global heart T2 and T2* values were obtained by averaging the values in all 16 myocardial segments. The normal T2 range was established as mean±2 standard deviations on data acquired on 80 healthy volunteers (males: 48-56 ms and females: 50-57 ms). The lower limit of normal for global heart T2*, established on the same healthy population, was 32 ms. Results.A significant correlation was detected between global heart T2 and T2* values (R=0.577; P<0.0001) (Figure). Out of the 113 (84.9%) patients with a normal global heart T2* value, none had a decreased global heart T2 value, while 58 (51.3%) had an increased T2 value. Out of the 20 patents with a decreased global heart T2* value, only 10 (50%) had also a reduced T2 value. Conversely, 9 (45.0%) had a normal global heart T2 value and one (4.5) showed an increased T2 value. The 59 patients with increased global heart T2 value were significantly older than the remaining patients (40.8±10.5 vs 36.4±11.6 years; P=0.019) Conclusion.All patients with decreased T2 value had also a decreased T2* value and in half of the patients iron load was undetected by T2, suggesting that T2 mapping does not offer any advantage in terms of sensitivity for MIO assessment. However, more than half of TM patients had an increased T2 value, thus may be caused by the presence of myocardial inflammation and/or edema. So, T2 mapping could reveal subclinical myocardial involvement in TM patients. Figure Disclosures Pistoia: Chiesi Farmaceutici S.p.A.:Other: speakers' honoraria.Meloni:Chiesi Farmaceutici S.p.A.:Other: speakers' honoraria.

scholarly journals High resolution MRI of the brain at 4.7 Tesla using fast spin echo imaging

2003 ◽  
Vol 76 (909) ◽  
pp. 631-637 ◽  
Author(s):  
E De Vita ◽  
D L Thomas ◽  
S Roberts ◽  
H G Parkes ◽  
R Turner ◽  
...  
Keyword(s):  
High Resolution ◽  
Spin Echo ◽  
Fast Spin Echo ◽  
High Resolution Mri ◽  
The Brain ◽  
Fast Spin

scholarly journals T2 mapping of the heart with a double-inversion radial fast spin-echo method with indirect echo compensation

2015 ◽  
Vol 17 (1) ◽  
pp. 24 ◽  
Author(s):  
Tomoe Hagio ◽  
Chuan Huang ◽  
Aiden Abidov ◽  
Jaspreet Singh ◽  
Bujji Ainapurapu ◽  
...  
Keyword(s):  
Spin Echo ◽  
T2 Mapping ◽  
Fast Spin Echo ◽  
Fast Spin

Patellar Malalignment Is Associated With Patellofemoral Lesions and Cartilage Relaxation Times After Hamstring Autograft Anterior Cruciate Ligament Reconstruction

2020 ◽  
Vol 48 (9) ◽  
pp. 2242-2251
Author(s):  
Tzu-Chieh Liao ◽  
Alejandro G. Morales Martinez ◽  
Valentina Pedoia ◽  
Benjamin C. Ma ◽  
Xiaojuan Li ◽  
...  
Keyword(s):  
Lateral Displacement ◽  
Spin Echo ◽  
Cruciate Ligament ◽  
Relaxation Times ◽  
Fast Spin Echo ◽  
Healthy Controls ◽  
Resonance Imaging ◽  
Anterior Cruciate ◽  
Fast Spin ◽  
And Cartilage

Background: There is growing evidence suggesting a link between patellofemoral joint (PFJ) osteoarthritis in anterior cruciate ligament (ACL)–reconstructed knees and altered joint alignment. Purpose: To determine whether patellar alignment differs between participants with and without ACL reconstruction (ACLR) and to identify possible associations between patellar alignment and PFJ osteoarthritis features over 3 years. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 37 participants with ACLR (sex, 23 male; mean ± SD age, 28.1 ± 7.4 years) and 20 healthy controls (13 male; 30.4 ± 4.8 years) participated. Patients underwent magnetic resonance imaging: (1) sagittal T2-weighted fat-saturated fast spin echo images to calculate patellar alignment, (2) sagittal 3-dimensional intermediate-weighted fast spin echo Cube sequence for clinical morphological grading (modified Whole-Organ Magnetic Resonance Imaging Score [WORMS]), and (3) sagittal combined T1ρ/T2 mapping sequence for performing voxel-based relaxometry. Patellar alignment of the ACLR knees were assessed at 6 months (baseline). One-way analysis of variance was used to compare patellar alignment among the ACLR (at 6 months), contralateral, and control knees. Within the ACLR group, a logistic regression model was used to identify if patellar alignment measures at baseline were risk factors for worsening of PFJ structural changes over 3 years. Statistical parametric mapping was used to evaluate the longitudinal associations between patellar alignment and cartilage relaxation times at 3 years. Results: When compared with control knees, ACLR knees exhibited a laterally and anteriorly displaced patella ( P = .045 and P = .041), less flexion ( P = .031), and less lateral spin ( P = .012). Furthermore, excessive lateral displacement was a significant predictor of worsening of WORMS ( P = .050). Lateral displacement was positively correlated with increased T1ρ and T2 in the patellar and trochlear cartilage at 3 years. Patellar lateral spin revealed similar negative findings. Conclusion: Participants with ACLR exhibited a laterally and anteriorly displaced patella, less flexion, and less lateral spin when compared with healthy controls. Excessive patellar lateral displacement was the strongest predictor to the development of PFJ osteoarthritis features longitudinally.

Increased accuracy in MR diagnosis of uveal melanoma by carbohydrate loading

1998 ◽  
Vol 39 (3) ◽  
pp. 239-242
Author(s):  
K.-Å. Thuomas ◽  
P. Naeser ◽  
A. Wrigstad
Keyword(s):  
Uveal Melanoma ◽  
Spindle Cell ◽  
Spin Echo ◽  
Tumour Size ◽  
Relaxation Times ◽  
Fast Spin Echo ◽  
Subtraction Technique ◽  
Mixed Cell ◽  
Carbohydrate Loading ◽  
Fast Spin

Purpose: To evaluate patients with clinically diagnosed uveal melanoma Material and Methods: Forty-eight consecutive patients were examined with spin-echo (SE) and fast spin-echo (FSE) MR sequences that utilized glucosefructose enhancement together with a subtraction technique on a 1.5 T unit Results: Twenty-seven patients were enucleated and the eyes histologically examined for tumours (spindle cell, mixed cell, and epitheloid cell). The remaining patients were referred for other treatment. There were no significant differences in T2 although T2 was longer in the amelanotic lesions. Carbohydrate loading in combination with a subtraction technique gave: an increased signal intensity; a prolongation of T2; and an increased tumour size. The FSE sequences were as good as the SE sequences in the visualization of uveal malignant melanoma Conclusion: MR imaging performed with carbohydrate loading registers metabolic changes induced in the tumour. This gives the method great validity in the diagnosis of uveal melanoma. The method is especially useful in amelanotic tumours that have longer relaxation times than melanotic tumours. The SE technique can be replaced with the FSE technique

High-resolution T2-weighted fast spin-echo MRI of the pituitary: Comparison with T1-weighted imaging without and with contrast

1998 ◽  
Vol 5 (10) ◽  
pp. 748
Author(s):  
Leo J. Wolansky ◽  
Jamil Ibrahim ◽  
Huey-Jen Lee ◽  
Satyaveni B. Rao ◽  
Robert Brautigan
Keyword(s):  
High Resolution ◽  
Spin Echo ◽  
Fast Spin Echo ◽  
Fast Spin

Quantitative in vivo T2 mapping using fast spin echo techniques – A linear correction procedure

NeuroImage ◽  
2017 ◽  
Vol 157 ◽  
pp. 476-485 ◽  
Author(s):  
Ulrike Nöth ◽  
Manoj Shrestha ◽  
Jan-Rüdiger Schüre ◽  
Ralf Deichmann
Keyword(s):  
Spin Echo ◽  
T2 Mapping ◽  
Fast Spin Echo ◽  
Correction Procedure ◽  
Linear Correction ◽  
Fast Spin

scholarly journals High-resolution proton density weighted three-dimensional fast spin echo (3D-FSE) of the knee with IDEAL at 1.5 tesla: Comparison with 3D-FSE and 2D-FSE-initial experience

2011 ◽  
Vol 35 (2) ◽  
pp. 361-369 ◽  
Author(s):  
Colm J. McMahon ◽  
Ananth J. Madhuranthakam ◽  
Jim S. Wu ◽  
Corrie M. Yablon ◽  
Jesse L. Wei ◽  
...  
Keyword(s):  
High Resolution ◽  
Spin Echo ◽  
Three Dimensional ◽  
Fast Spin Echo ◽  
Proton Density ◽  
Initial Experience ◽  
Fast Spin
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