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1.
Esther E. Bron Jasper van Tiel Henk Smit Dirk H. J. Poot Wiro J. Niessen Gabriel P. Krestin Harrie Weinans Edwin H. G. Oei Gyula Kotek Stefan Klein 《European radiology》2013,23(1):246-252
Objectives
To evaluate the effect of automated registration in delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) of the knee on the occurrence of movement artefacts on the T1 map and the reproducibility of region-of-interest (ROI)-based measurements.Methods
Eleven patients with early-stage knee osteoarthritis and ten healthy controls underwent dGEMRIC twice at 3?T. Controls underwent unenhanced imaging. ROIs were manually drawn on the femoral and tibial cartilage. T1 calculation was performed with and without registration of the T1-weighted images. Automated three-dimensional rigid registration was performed on the femur and tibia cartilage separately. Registration quality was evaluated using the square root Cramér–Rao lower bound (CRLBσ). Additionally, the reproducibility of dGEMRIC was assessed by comparing automated registration with manual slice-matching.Results
Automated registration of the T1-weighted images improved the T1 maps as the 90% percentile of the CRLBσ was significantly (P?<?0.05) reduced with a median reduction of 55.8 ms (patients) and 112.9 ms (controls). Manual matching and automated registration of the re-imaged T1 map gave comparable intraclass correlation coefficients of respectively 0.89/0.90 (patients) and 0.85/0.85 (controls).Conclusions
Registration in dGEMRIC reduces movement artefacts on T1 maps and provides a good alternative to manual slice-matching in longitudinal studies.Key Points
? Quantitative MRI is increasingly used for biomedical assessment of knee articular cartilage ? Image registration leads to more accurate quantification of cartilage quality and damage ? Movement artefacts in delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) are reduced ? Automated image registration successfully aligns baseline and follow-up dGEMRIC examinations ? Reproducibility of dGEMRIC with registration is similar to that using manual slice-matching 相似文献2.
Andrea Lazik Jens M. Theysohn Christina Geis Sören Johst Mark E. Ladd Harald H. Quick Oliver Kraff 《European radiology》2016,26(5):1245-1253
Objectives
To evaluate the technical feasibility and applicability of quantitative MR techniques (delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), T2 mapping, T2* mapping) at 7 T MRI for assessing hip cartilage.Methods
Hips of 11 healthy volunteers were examined at 7 T MRI with an 8-channel radiofrequency transmit/receive body coil using multi-echo sequences for T2 and T2* mapping and a dual flip angle gradient-echo sequence before (T10) and after intravenous contrast agent administration (T1Gd; 0.2 mmol/kg Gd-DTPA2? followed by 0.5 h of walking and 0.5 h of rest) for dGEMRIC. Relaxation times of cartilage were measured manually in 10 regions of interest. Pearson’s correlations between R1delta?=?1/T1Gd???1/T10 and T1Gd and between T2 and T2* were calculated. Image quality and the delineation of acetabular and femoral cartilage in the relaxation time maps were evaluated using discrete rating scales.Results
High correlations were found between R1delta and T1Gd and between T2 and T2* relaxation times (all p?<?0.01). All techniques delivered diagnostic image quality, with best delineation of femoral and acetabular cartilage in the T2* maps (mean 3.2 out of a maximum of 4 points).Conclusions
T1, T2 and T2* mapping of hip cartilage with diagnostic image quality is feasible at 7 T. To perform dGEMRIC at 7 T, pre-contrast T1 mapping can be omitted.Key Points
? dGEMRIC of hip cartilage with diagnostic image quality is feasible at 7 T. ? To perform dGEMRIC at 7 T, pre-contrast T1 mapping can be omitted. ? T2(*) mapping of hip cartilage with diagnostic image quality is feasible at 7 T. ? T2 and T2* relaxation times of cartilage were highly correlated at 7 T. ? Best delineation of femoral and acetabular cartilage was found in T2* maps.3.
Bernd Bittersohl MD Harish S. Hosalkar MD MBMS FCPS DNB Tanja Haamberg MD Young‐Jo Kim MD Stefan Werlen MD Klaus A. Siebenrock MD Tallal C. Mamisch MD 《Journal of magnetic resonance imaging : JMRI》2009,30(1):224-228
Purpose
To investigate the reproducibility of dGEMRIC in the assessment of cartilage health of the adult asymptomatic hip joint.Materials and Methods
Fifteen asymptomatic volunteers (mean age, 26.3 years ± 3.0) were preliminarily studied. Any volunteer that was incidentally diagnosed with damaged cartilage on MRI (n = 5) was excluded. Ten patients that had no evidence of prior cartilage damage (mean age, 26.2 years ± 3.4) were evaluated further in this study. The reproducibility of dGEMRIC was assessed with two T1Gd exams performed 4 weeks apart in these volunteers. The protocol involved an initial standard MRI to confirm healthy cartilage, which was then followed by dGEMRIC. The second scan included only the repeat dGEMRIC. Region of interest (ROI) analyses for T1Gd‐measurement was performed in seven radial reformats. Statistical analysis included the student's t‐test and intra‐class correlation (ICC) measurement to assess reproducibility.Results
Overall 70 ROIs were studied. Mean cartilage T1Gd values at various loci ranged from 560.9 ms to 684.4 ms at the first set of readings and 551.5 ms to 662.2 ms in the second one. The mean difference per region of interest between the two T1Gd‐measurements ranged from 21.4 ms (3.7%) to 45.0 ms (6.8%), which was not found to be statistically significant (P = 0.153). There was a high reproducibility detected (ICC range, 0.667–0.915). Intra‐ and Inter‐observer analyses proved a high agreement for T1Gd assessment (0.973 and 0.932).Conclusion
We found dGEMRIC to be a reliable tool in the assessment of cartilage health status in adult hip joints. J. Magn. Reson. Imaging 2009;30:224–228. © 2009 Wiley‐Liss, Inc. 相似文献4.
Buchbender C Scherer A Kröpil P Körbl B Quentin M Reichelt DCh Lanzman RS Mathys C Blondin D Bittersohl B Zilkens C Hofer M Wittsack HJ Schneider M Antoch G Ostendorf B Miese F 《Skeletal radiology》2012,41(6):685-692
Purpose
To prospectively evaluate four non-invasive markers of cartilage quality—T2* mapping, native T1 mapping, dGEMRIC and ΔR1—in healthy volunteers and rheumatoid arthritis (RA) patients.Materials and methods
Cartilage of metacarpophalangeal (MCP) joints II were imaged in 28 consecutive subjects: 12 healthy volunteers [9 women, mean (SD) age 52.67 (9.75) years, range 30–66] and 16 RA patients with MCP II involvement [12 women, mean (SD) age 58.06 (12.88) years, range 35–76]. Sagittal T2* mapping was performed with a multi-echo gradient-echo on a 3?T MRI scanner. For T1 mapping the dual flip angle method was applied prior to native T1 mapping and 40?min after gadolinium application (delayed gadolinium-enhanced MRI of cartilage, dGEMRIC, T1Gd). The difference in the longitudinal relaxation rate induced by gadolinium (ΔR1) was calculated. The area under the receiver operating characteristic curve (AROC) was used to test for differentiation of RA patients from healthy volunteers.Results
dGEMRIC (AUC 0.81) and ΔR1 (AUC 0.75) significantly differentiated RA patients from controls. T2* mapping (AUC 0.66) and native T1 mapping (AUC 0.66) were not significantly different in RA patients compared to controls.Conclusions
The data support the use of dGEMRIC for the assessment of MCP joint cartilage quality in RA. T2* and native T1 mapping are of low diagnostic value. Pre-contrast T1 mapping for the calculation of ΔR1 does not increase the diagnostic value of dGEMRIC. 相似文献5.
Zilkens C Miese F Kim YJ Hosalkar H Antoch G Krauspe R Bittersohl B 《European journal of radiology》2012,81(11):3420-3425
Purpose
To assess acetabular and femoral hip joint cartilage with three-dimensional (3D) delayed gadolinium-enhanced magnetic resonance imaging (dGEMRIC) in patients with degeneration of hip joint cartilage and asymptomatic controls with morphologically normal appearing cartilage.Methods and materials
A total of 40 symptomatic patients (18 males, 22 females; mean age: 32.8 ± 10.2 years, range: 18–57 years) with different hip joint deformities including femoroacetabular impingement (n = 35), residual hip dysplasia (n = 3) and coxa magna due to Legg–Calve–Perthes disease in childhood (n = 2) underwent high-resolution 3D dGEMRIC for the evaluation of acetabular and femoral hip joint cartilage. Thirty-one asymptomatic healthy volunteers (12 males, 19 females; mean age: 24.5 ± 1.8 years, range: 21–29 years) without underlying hip deformities were included as control. MRI was performed at 3 T using a body matrix phased array coil. Region of interest (ROI) analyses for T1Gd assessment was performed in seven regions in the hip joint, including anterior to superior and posterior regions.Results
T1Gd mapping demonstrated the typical pattern of acetabular cartilage consistent with a higher glycosaminoglycan (GAG) content in the main weight-bearing area. T1Gd values were significantly higher in the control group than in the patient group whereas significant differences in T1Gd values corresponding to the amount of cartilage damage were noted both in the patient group and in the control group.Conclusions
Our study demonstrates the potential of high-resolution 3D dGEMRIC at 3 T for separate acetabular and femoral hip joint cartilage assessment in various forms of hip joint deformities. 相似文献6.
Bernd Bittersohl Falk R. Miese Christin Dekkers Hüseyin Senyurt Jörn Kircher Hans-Jörg Wittsack Gerald Antoch Rüdiger Krauspe Christoph Zilkens 《European radiology》2013,23(5):1367-1374
Objectives
To establish baseline T2* and T1Gd values of glenohumeral cartilage at 3 T.Methods
Forty asymptomatic volunteers (mean age: 24.8?±?2.2 years) without shoulder abnormalities were included. The MRI protocol comprised a double-echo steady-state (DESS) sequence for morphological cartilage evaluation, a gradient-echo multiecho sequence for T2* assessment, and a gradient-echo dual-flip-angle sequence for T1Gd mapping. Statistical assessment involved a one-way analysis of variance (ANOVA) to identify the differences between various regions of the glenohumeral joint and intraclass correlation (ICC) analysis comparing repetitive T2* and T1Gd measures to assess intra- and interobserver reliability.Results
Both techniques revealed significant differences between superior and inferior glenohumeral cartilage demonstrating higher T2* (26.2 ms vs. 23.2 ms, P value?<?0.001) and T1Gd (750.1 ms vs. 720.2 ms, P value?=?0.014) values in the superior regions. No trend was observed in the anterior-posterior measurement (P value range: 0.279–1.000). High intra- and interobserver agreement (ICC value range: 0.895–0.983) was noted for both T2* and T1Gd mapping.Conclusions
T2* and T1Gd mapping are reliable in the assessment of glenohumeral cartilage. The values from this study can be used for comparison to identify cartilage degeneration in patients suffering from shoulder joint abnormalities.Key Points
? T2* mapping and dGEMRIC are sensitive to collagen degeneration and proteoglycan depletion. ? This study aimed to establish baseline T2*/dGEMRIC values of glenohumeral cartilage. ? Both techniques revealed significant differences between superior and inferior glenohumeral cartilage. ? High intra-/interreader agreement was noted for both T2* mapping and dGEMRIC. ? These baseline normal values should be useful when identifying potential degeneration. 相似文献7.
Christoph Zilkens Falk Miese Monika Herten Sabine Kurzidem Marcus Jäger Dietmar König Gerald Antoch Rüdiger Krauspe Bernd Bittersohl 《European journal of radiology》2013
Objective
To validate gradient-echo three-dimensional (3D) delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) by means of histological analyses in the assessment of hip joint cartilage.Materials and methods
Twenty-one femoral head specimens collected from 21 patients (7 males, 14 females, mean age: 60.9 ± 9.6 years; range: 37.6–77.3 years), who underwent total hip replacement for symptomatic hip joint osteoarthritis, underwent MRI and histological assessment. A region of 2 cm2 at the weight-bearing area was marked with four pins to enable multi-planar MRI reformatting to be matched with histological sections. MRI was performed at 3 T with a 3D double-echo steady-state (DESS) sequence for morphological cartilage assessment and 3D Volumetric Interpolated Breathhold Examination (VIBE) for T1Gd mapping. Histological sections were evaluated according to the Mankin score system. Total Mankin score, grade of toluidine staining (sensitive for glycosaminoglycan content) and a modified Mankin score classification system with four sub-groups of cartilage damage were correlated with MRI data.Results
Spearman's rho correlation analyses revealed a statistically significant correlation between T1Gd mapping and histological analyses in all categories including total Mankin score (r = −0.658, p-value ≤ 0.001), toluidine staining (r = −0.802, p-value < 0.001) and modified Mankin score (r = −0.716, p-value < 0.001). The correlation between morphological MRI and histological cartilage assessment was statistically significant but inferior to the biochemical cartilage MRI (r-values ranging from −0.411 to 0.525, p-values < 0.001).Conclusions
Gradient-echo dGEMRIC is reliable while offering the unique features of high image resolution and 3D biochemically sensitive MRI for the assessment of early cartilage degeneration. 相似文献8.
Christoph Zilkens Falk MieseBernd Bittersohl Marcus JägerJohannes Schultz Arne HolsteinYoung-jo Kim Michael B. MillisTallal C. Mamisch Rüdiger Krauspe 《European journal of radiology》2011,79(3):400-406
Objective
The aim of this study was to assess the glycosaminoglycan (GAG) content in hip joint cartilage in mature hips with a history of slipped capital femoral epiphysis (SCFE) using delayed gadolinium-enhanced MRI of cartilage (dGEMRIC).Methods
28 young-adult subjects (32 hips) with a mean age of 23.8 ± 4.0 years (range: 18.1-30.5 years) who were treated for mild or moderate SCFE in adolescence were included into the study. Hip function and clinical symptoms were evaluated with the Harris hip score (HHS) system at the time of MRI. Plain radiographic evaluation included Tonnis grading, measurement of the minimal joint space width (JSW) and alpha-angle measurement. The alpha-angle values were used to classify three sub-groups: group 1 = subjects with normal femoral head-neck offset (alpha-angle <50°), group 2 = subjects with mild offset decrease (alpha-angle 50°-60°), and group 3 = subjects with severe offset decrease (alpha-angle >60°).Results
There was statistically significant difference noted for the T1Gd values, lateral and central, between group 1 and group 3 (p-values = 0.038 and 0.041). The T1Gd values measured within the lateral portion were slightly lower compared with the T1Gd values measured within the central portion that was at a statistically significance level (p-value <0.001). HHS, Tonnis grades and JSW revealed no statistically significant difference.Conclusion
By using dGEMRIC in the mid-term follow-up of SCFE we were able to reveal degenerative changes even in the absence of joint space narrowing that seem to be related to the degree of offset pathology. The dGEMRIC technique may be a potential diagnostic modality in the follow-up evaluation of SCFE. 相似文献9.
Agnes G. d’Entremont Shannon H. Kolind Burkhard Mädler David R. Wilson Alexander L. MacKay 《Skeletal radiology》2014,43(3):331-344
Objective
To evaluate the effect of metal artifact reduction techniques on dGEMRIC T1 calculation with surgical hardware present.Materials and methods
We examined the effect of stainless-steel and titanium hardware on dGEMRIC T1 maps. We tested two strategies to reduce metal artifact in dGEMRIC: (1) saturation recovery (SR) instead of inversion recovery (IR) and (2) applying the metal artifact reduction sequence (MARS), in a gadolinium-doped agarose gel phantom and in vivo with titanium hardware. T1 maps were obtained using custom curve-fitting software and phantom ROIs were defined to compare conditions (metal, MARS, IR, SR).Results
A large area of artifact appeared in phantom IR images with metal when TI?≤?700 ms. IR maps with metal had additional artifact both in vivo and in the phantom (shifted null points, increased mean T1 (+151 % IR ROIartifact) and decreased mean inversion efficiency (f; 0.45 ROIartifact, versus 2 for perfect inversion)) compared to the SR maps (ROIartifact: +13 % T1 SR, 0.95 versus 1 for perfect excitation), however, SR produced noisier T1 maps than IR (phantom SNR: 118 SR, 212 IR). MARS subtly reduced the extent of artifact in the phantom (IR and SR).Conclusions
dGEMRIC measurement in the presence of surgical hardware at 3T is possible with appropriately applied strategies. Measurements may work best in the presence of titanium and are severely limited with stainless steel. For regions near hardware where IR produces large artifacts making dGEMRIC analysis impossible, SR-MARS may allow dGEMRIC measurements. The position and size of the IR artifact is variable, and must be assessed for each implant/imaging set-up. 相似文献10.
Jasper van Tiel Gyula Kotek Max Reijman Pieter K. Bos Esther E. Bron Stefan Klein Jan A. N. Verhaar Gabriel P. Krestin Harrie Weinans Edwin H. G. Oei 《European radiology》2014,24(9):2261-2270
Objectives
To assess (1) whether normal and degenerated menisci exhibit different T1GD on delayed gadolinium-enhanced MRI of the meniscus (dGEMRIM), (2) the reproducibility of dGEMRIM and (3) the correlation between meniscus and cartilage T1GD in knee osteoarthritis (OA) patients.Methods
In 17 OA patients who underwent dGEMRIM twice within 7 days, meniscus and cartilage T1GD was calculated. Meniscus pathology was evaluated on conventional MRI. T1GD in normal and degenerated menisci were compared using a Student’s t-test. Reproducibility was assessed using ICCs. Pearson’s correlation was calculated between meniscus and cartilage T1GD.Results
A trend towards lower T1GD in degenerated menisci (mean: 402 ms; 95 % CI: 359–444 ms) compared to normal menisci (mean: 448 ms; 95 % CI: 423–473 ms) was observed (p?=?0.05). Meniscus T1GD ICCs were 0.85–0.90. The correlation between meniscus and cartilage T1GD was moderate in the lateral (r?=?0.52–0.75) and strong in the medial compartment (r?=?0.78–0.94).Conclusions
Our results show that degenerated menisci have a clear trend towards lower T1GD compared to normal menisci. Since these results are highly reproducible, meniscus degeneration may be assessed within one delayed gadolinium-enhanced MRI simultaneously with cartilage. The strong correlation between meniscus and cartilage T1GD suggests concomitant degeneration in both tissues in OA, but also suggests that dGEMRIC may not be regarded entirely as sulphated glycosaminoglycan specific.Key Points
? dGEMRIM T1 GD can possibly be used to assess meniscal degeneration; ? dGEMRIM yields highly reproducible meniscal T1 GD in early stage osteoarthritic patients; ? Concomitant degeneration of cartilage and meniscus tissue occurs in early stage osteoarthritis; ? dGEMRIC cannot be regarded as entirely sulphated glycosaminoglycan specific. 相似文献11.
Taehee Kim Byoung-Hyun Min Seung-Hyun Yoon Hakil Kim Sunghoon Park Hyun Young Lee Kyu-Sung Kwack 《Skeletal radiology》2014,43(7):947-954
Objective
The aim of this study was to evaluate the correlations between T2 value, T2* value, and histological grades of degenerated human articular cartilage.Materials and methods
T2 mapping and T2* mapping of nine tibial osteochondral specimens were obtained using a 3-T MRI after total knee arthroplasty. A total of 94 ROIs were analyzed. Histological grades were assessed using the David–Vaudey scale. Spearman’s rho correlation analysis and Pearson’s correlation analysis were performed.Results
The mean relaxation values in T2 map with different histological grades (0, 1, 2) of the cartilage were 51.9?±?9.2 ms, 55.8?±?12.8 ms, and 59.6?±?10.2 ms, respectively. The mean relaxation values in T2* map with different histological grades (0, 1, 2) of the cartilage were 20.3?±?10.3 ms, 21.1?±?12.4 ms, and 15.4?±?8.5 ms, respectively. Spearman’s rho correlation analysis confirmed a positive correlation between T2 value and histological grade (ρ?=?0.313, p?<?0.05). Pearson’s correlation analysis revealed a significant negative correlation between T2 and T2* (r?=??0.322, p?<?0.05). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, this correlation was not statistically significant in this study (ρ?=??0.192, p?=?0.129).Conclusions
T2 mapping was correlated with histological degeneration, and it may be a good biomarker for osteoarthritis in human articular cartilage. However, the strength of the correlation was weak (ρ?=?0.313). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, the correlation was not statistically significant. Therefore, T2 mapping may be more appropriate for the initial diagnosis of articular cartilage degeneration in the knee joint. Further studies on T2* mapping are needed to confirm its reliability and mechanism in cartilage degeneration. 相似文献12.
M. Sauerschnig J. S. Bauer L. Kohn S. Hinterwimmer S. Landwehr K. Woertler P. M. Jungmann W. Koestler P. Niemeyer A. B. Imhoff G. M. Salzmann 《Knee surgery, sports traumatology, arthroscopy》2014,22(6):1396-1403
Purpose
To investigate whether the static knee alignment affects articular cartilage ultrastructures when measured using T2 relaxation among asymptomatic subjects.Methods
Both knee joints (n = 96) of 48 asymptomatic volunteers (26 females, 22 males; 25.4 ± 1.7 years; no history of major knee trauma or surgery) were evaluated clinically (Lysholm, Tegner) and by MRI (hip–knee–ankle angle, standard knee protocol, T2 mapping). Group (n = 4) division was as follows: neutral (<1° varus/valgus), mild varus (2°–4° varus), severe varus (>4° varus) and valgus (2°–4° valgus) deformity with n = 12 subjects/group; n = 24 knees/group. Regions of interest (ROI) for T2 assessment were placed within full-thickness cartilage across the whole joint surface and were divided respecting compartmental as well as functional joint anatomy.Results
Leg alignment was 0.7° ± 0.5° varus among neutral, 3.0° ± 0.6° varus among mild varus, 5.0° ± 1.1° varus among severe varus and 2.5° ± 0.7° valgus among valgus group subjects and thus significantly different. No differences between the groups emerged from clinical measures. No morphological pathology was detected in any knee joint. Global T2 values (42.3 ± 2.3; 37.7–47.9 ms) of ROIs placed within every knee joint per subject were not different between alignment groups or between genders, respectively.Conclusion
Static frontal plane leg malalignment does not affect cartilage ultrastructure among young, asymptomatic individuals as measured by T2 quantitative imaging.Level of evidence
Cross-sectional study, Level II-III. 相似文献13.
Rachel K. Surowiec Erin P. Lucas Charles P. Ho 《Knee surgery, sports traumatology, arthroscopy》2014,22(6):1385-1395
Purpose
Early diagnosis of cartilage degeneration and longitudinal tracking of cartilage health including repair following surgical intervention would benefit from the ability to detect and monitor changes of the articular cartilage non-invasively and before gross morphological alterations appear.Methods
Quantitative MR imaging has shown promising results with various imaging biomarkers such as T2 mapping, T1 rho and dGEMRIC demonstrating sensitivity in the detection of biochemical alterations within tissues of interest. However, acquiring accurate and clinically valuable quantitative data has proven challenging, and the reproducibility of the quantitative mapping technique and its values are essential. Although T2 mapping has been the focus in this discussion, all quantitative mapping techniques are subject to the same issues including variability in the imaging protocol, unloading and exercise, analysis, scanner and coil, calculation methods, and segmentation and registration concerns.Results
The causes for variability between time points longitudinally in a patient, among patients, and among centres need to be understood further and the issues addressed.Conclusions
The potential clinical applications of quantitative mapping are vast, but, before the clinical community can take full advantage of this tool, it must be automated, standardized, validated, and have proven reproducibility prior to its implementation into the standard clinical care routine. 相似文献14.
Andrea Lazik-Palm Oliver Kraff Christina Geis Sören Johst Juliane Goebel Mark E. Ladd Harald H. Quick Jens M. Theysohn 《European radiology》2016,26(11):3923-3931
Objectives
To investigate the influence of intravenous gadolinium on cartilage T2 and T2* relaxation times and on morphological image quality at 7-T hip MRI.Methods
Hips of 11 healthy volunteers were examined at 7 T. Multi-echo sequences for T2 and T2* mapping, 3D T1 volumetric interpolated breath-hold examination (VIBE) and double-echo steady-state (DESS) sequences were acquired before and after intravenous application of gadolinium according to a delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) protocol. Cartilage relaxation times were measured in both scans. Morphological sequences were assessed quantitatively using contrast ratios and qualitatively using a 4-point Likert scale. Student’s t-test, Pearson’s correlation (ρ) and Wilcoxon sign-rank test were used for statistical comparisons.Results
Pre- and post-contrast T2 and T2* values were highly correlated (T2: acetabular: ρ?=?0.76, femoral: ρ?=?0.77; T2*: acetabular: ρ?=?0.80, femoral: ρ?=?0.72). Gadolinium enhanced contrasts between cartilage and joint fluid in DESS and T1 VIBE according to the qualitative (p?=?0.01) and quantitative (p?<?0.001) analysis. The delineation of acetabular and femoral cartilage and the labrum predominantly improved with gadolinium.Conclusions
Gadolinium showed no relevant influence on T2 or T2* relaxation times and improved morphological image quality at 7 T. Therefore, morphological and quantitative sequences including dGEMRIC can be conducted in a one-stop-shop examination.Key Points
? Hip cartilage T2 values correlate highly before and after gadolinium at 7 T ? Hip cartilage T2* values correlate highly before and after enhancement at 7 T ? Morphological hip cartilage imaging benefits from intravenous gadolinium at 7 T ? The delineation of acetabular and femoral cartilage can be improved by gadolinium ? Morphological and quantitative sequences including dGEMRIC can be combined as a one-stop-shop examination15.
Stephan E. Domayer Siegfried Trattnig MD David Stelzeneder MD Clemens Hirschfeld Sebastian Quirbach MD Ronald Dorotka MD Stefan Nehrer MD Katja Pinker MD Jenny Chan BS Tallal Charles Mamisch MD Martin Dominkus MD Götz H. Welsch MD 《Journal of magnetic resonance imaging : JMRI》2010,31(3):732-739
Purpose:
To demonstrate the feasibility of delayed gadolinium‐enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) in the ankle at 3 T and to obtain preliminary data on matrix associated autologous chondrocyte (MACI) repair tissue.Materials and Methods:
A 3D dual flip angle sequence was used with an eight‐channel multipurpose coil at 3 T to obtain T1 maps both pre‐ and postintravenous contrast agent (Magnevist, 0.2 mM/kg). Postcontrast T1 over time was evaluated in three volunteers; a modified dGEMRIC protocol was then used to assess 10 cases after MACI in the ankle.Results:
Forty‐five minutes were found sufficient for maximum T1 decrease. MACI cases had a precontrast mean T1 of 1050 ± 148.4 msec in reference cartilage (RC) and 1080 ± 165.6 msec in repair tissue (RT). Postcontrast T1 decreased to 590 ± 134.0 msec in RC and 554 ± 133.0 msec in RT. There was no significant difference between the delta relaxation rates in RT (9.44 × 10?4 s?1) and RC (8.04 × 10?4 s?1, P = 0.487). The mean relative delta relaxation rate was 1.34 ± 0.83.Conclusion:
It is feasible to assess the thin cartilage layers of the ankle with dGEMRIC at 3 T; MACI can yield RT with properties similar to articular cartilage. J. Magn. Reson. Imaging 2010;31:732–739. © 2010 Wiley‐Liss, Inc.16.
Wei Li MD Hongyan Du MS Rachel Scheidegger BA Ying Wu MD Pottumarti V. Prasad PhD 《Journal of magnetic resonance imaging : JMRI》2009,29(2):494-497
Purpose
To evaluate if the difference between pre‐ and post‐Gd‐DTPA2‐ relaxation rate (ΔR1) provides better differentiation of osteoarthritic patients (OA) from healthy subjects (HS) with dGEMRIC, as compared to post‐Gd‐DTPA2‐ spin‐lattice relaxation time (T1Gd).Materials and Methods
Seventeen OA and 14 HS underwent pre‐ and 90 minutes postcontrast (Gd‐DTPA2‐) magnetic resonance imaging (MRI) of the knee, using inversion recovery fast spin‐echo and/or Lock–Locker sequences for T1 mapping. Effect sizes for T1pre, T1Gd, and ΔR1 were calculated, and receiver operating characteristic (ROC) curve and regression analysis were also performed to assess the effectiveness of each parameter in the separation of OA and HS.Results
T1Gd and ΔR1 were almost identical in terms of areas under ROC curves (0.903 and 0.914, respectively), and effect sizes (1.34 and 1.31, respectively). These were significantly higher than T1pre. In addition, a high inverse correlation was observed between ΔR1 vs. T1Gd (R = 0.96).Conclusion
Either T1Gd or ΔR1 could be used as an index in the evaluation of native cartilage. However, considering the practical logistical cost involved in terms of time and effort to acquire precontrast T1 measurements, our data further support the continued use of T1Gd as the dGEMRIC index in the evaluation of native cartilage. J. Magn. Reson. Imaging 2009;29:494–497. © 2009 Wiley‐Liss, Inc. 相似文献17.
Objectives
We compare the T1 and T2 relaxation times and magnetization transfer ratios (MTRs) of normal subjects and patients with osteoarthritis (OA) to evaluate the ability of these techniques to aid in the early diagnosis and treatment of OA.Materials and methods
The knee joints in 11 normal volunteers and 40 patients with OA were prospectively evaluated using T1 relaxation times as measured using delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), T2 relaxation times (multiple spin-echo sequence, T2 mapping), and MTRs. The OA patients were further categorized into mild, moderate, and severe OA.Results
The mean T1 relaxation times of the four groups (normal, mild OA, moderate OA, and severe OA) were: 487.3?±?27.7, 458.0?±?55.9, 405.9?±?57.3, and 357.9?±?36.7 respectively (p?<0.001). The mean T2 relaxation times of the four groups were: 37.8?±?3.3, 44.0?±?8.5, 50.9?±?9.5, and 57.4?±?4.8 respectively (p?<?0.001). T1 relaxation time decreased and T2 relaxation time increased with worsening degeneration of patellar cartilage. The result of the covariance analysis showed that the covariate age had a significant influence on T2 relaxation time (p?<?0.001). No significant differences between the normal and OA groups using MTR were noted.Conclusion
T1 and T2 relaxation times are relatively sensitive to early degenerative changes in the patellar cartilage, whereas the MTR may have some limitations with regard to early detection of OA. In addition, The T1 and T2 relaxation times negatively correlate with each other, which is a novel finding. 相似文献18.
Marius E. Mayerhoefer Goetz H. Welsch Tallal C. Mamisch Franz Kainberger Michael Weber Stefan Nemec Klaus M. Friedrich Albert Dirisamer Siegfried Trattnig 《European radiology》2010,20(2):443-449
Purpose
The purpose was to investigate the in vivo effects of unloading and compression on T1-Gd relaxation times in healthy articular knee cartilage.Materials and methods
Ten volunteers were enrolled, and dGEMRIC images of their right knee joints were obtained using 3.0-T MR at three timepoints: directly following exercise (“baseline”), approximately 15 min after unloading (“unloading”) and during application of a compressive force (50% of the body weight) generated by a loading device via a footplate (“compression”).Results
Our analysis of variance of pooled data from all cartilage zones demonstrated a significant mean T1-Gd decrease of 56.6 ms between baseline and compression (p?<?0.001), and a significant mean decrease of 42.1 ms between unloading and compression (p?<?0.001). No significant difference was found between baseline and unloading. Higher mean T1-Gd values were observed in the cartilage contact zone (central femoral and tibial zones; 698.3?±?162.2 ms) than in the non-contact zone (anterior and posterior femoral and tibial zones, and dorsal femoral zone; 662.9?±?149.3 ms; p?<?0.01).Conclusion
T1-Gd times appear to be sensitive to mechanical cartilage stress, and thus, further studies are warranted that investigate the relationship between the biochemical load response and the biomechanical properties of articular cartilage. 相似文献19.
Pieter Van Dyck Christoph Kenis Filip M. Vanhoenacker Valérie Lambrecht Kristien Wouters Jan L. Gielen Lieven Dossche Paul M. Parizel 《Knee surgery, sports traumatology, arthroscopy》2014,22(6):1376-1384
Purpose
The aim of this prospective study was to compare routine MRI scans of the knee at 1.5 and 3 T obtained in the same individuals in terms of their performance in the diagnosis of cartilage lesions.Methods
One hundred patients underwent MRI of the knee at 1.5 and 3 T and subsequent knee arthroscopy. All MR examinations consisted of multiplanar 2D turbo spin-echo sequences. Three radiologists independently graded all articular surfaces of the knee joint seen at MRI. With arthroscopy as the reference standard, the sensitivity, specificity, and accuracy of 1.5- and 3-T MRI for detecting cartilage lesions and the proportion of correctly graded cartilage lesions within the knee joint were determined and compared using resampling statistics.Results
For all readers and surfaces combined, the respective sensitivity, specificity, and accuracy for detecting all grades of cartilage lesions in the knee joint using MRI were 60, 96, and 87 % at 1.5 T and 69, 96, and 90 % at 3 T. There was a statistically significant improvement in sensitivity (p < 0.05), but not specificity or accuracy (n.s.) for the detection of cartilage lesions at 3 T. There was also a statistically significant (p < 0.05) improvement in the proportion of correctly graded cartilage lesions at 3 T as compared to 1.5 T.Conclusion
A 3-T MR protocol significantly improves diagnostic performance for the purpose of detecting cartilage lesions within the knee joint, when compared with a similar protocol performed at 1.5 T.Level of evidence
III. 相似文献20.
Bernd Vollnberg Torsten Koehlitz Tobias Jung Sven Scheffler Arnd Hoburg Dilruba Khandker Bernd Hamm Edzard Wiener Gerd Diederichs 《European radiology》2012,22(11):2347-2356