Cartilage T2 Values Research Articles

Association of cartilage [formula omitted] and [formula omitted] relaxation time measurement with hip osteoarthritis progression: A 5-year longitudinal study using voxel-based relaxometry and Z-score normalization

ObjectiveTo study the longitudinal changes of cartilage T1ρ and T2 relaxation time measurements in hip-OA patients. MethodsA calibration study compared two scanner data, Scanner-1 (GE Discovery MR750 3.0T) with unilateral acquisition protocol and Scanner-2 (GE Signa Premier 3.0T) with bilateral acquisition protocol, using nine subjects(average age ​= ​40.33 ​± ​13.53 years, 5 females), including one hip-OA subject. Quantified parameters from the Scanner-2 were adjusted using voxel-based relaxometry(VBR) and Z-score normalization to reduce the inter-scanner variability. Eighteen hip-OA Subjects (age ​= ​53.11 ​± ​14.96 years, 12 females) were recruited to the longitudinal variability study from 2016, comprising five assessments at 1-year intervals. Baseline to 3rd-year data used unilateral acquisition with Scanner-1, while 4th-year data used bilateral acquisition with Scanner-2. A linear mixed-effects model(LME) assessed trajectory analyses, with acquisition year, age, sex, body mass index(BMI), and Kellgren-Lawrence(KL) score as predictor variables and cartilage mean T1ρ and T2 values as outcomes. ResultsVBR analysis after Z-score normalization showed that only a few of the whole cartilage voxels had significant differences in T1ρ(femur-2.36 ​% and acetabular-3.23 ​%) and T2 (femur-2.30 ​% and acetabular-2.94 ​%) values between the scanners. The LME analysis showed that the BMI predictor variable was significantly correlated with the femur T1ρ (p ​< ​0.0001) and T2 (p ​< ​0.0001) and acetabular T1ρ (p ​< ​0.0001) and T2 (p ​< ​0.0001) cartilage region. ConclusionThe calibration study demonstrated the effectiveness of VBR and Z-score normalization in reducing inter-scanner variability. The longitudinal study revealed a significant correlation between T1ρ and T2 values of the cartilage and BMI; also the T1ρ and T2 values increased over time in some of the cartilage subregions.

Quantitative Evaluation of Knee Cartilage in Professional Martial Arts Athletes Using T2 Mapping: A Comparative Study.

Although the relationship between high-impact sports like football and basketball and the development of knee osteoarthritis is well established, the effect of martial arts on the knee joint remains unclear. To compare the imaging abnormalities of knee joints and T2 relaxation times of cartilage in professional martial arts athletes and healthy controls. Cross-sectional study. Hospital imaging center. Nine asymptomatic professional martial arts athletes and 18 healthy volunteers. We performed 3T magnetic resonance imaging of the knee on both legs of athletes and the dominant leg of controls. The magnetic resonance imaging protocol included conventional sequences used for morphological assessment (cartilage, meniscus, ligaments, joint effusion, and bone marrow edema) and T2 mapping used for quantitatively evaluating the cartilage. Knee cartilage was manually divided into 8 regions, and T2 relaxation times of the corresponding subregions were measured. Fisher exact test and t test were used to compare the frequency of lesions and cartilage T2 values both between groups and between the athletes' limbs. P < .05 was considered significant. Professional martial arts athletes exhibited significantly higher frequencies of cartilage (55.6% vs 11.1%, P = .023) and ligament lesions (66.7% vs 16.7%, P = .026) compared with the control group. Athletes showed higher T2 values in 3 distinct cartilage segments: the central weight-bearing segment of the medial femoral condyle (P = .006), the medial tibial plateau (P = .012), and the trochlea (P = .032), when compared with the controls. Additionally, the dominant leg of athletes showed significantly higher T2 values compared with the nondominant leg. The findings demonstrated the impact of martial arts on the knee joint, characterized by higher prevalence of lesions and elevated cartilage T2 values, particularly in the medial compartment. The dominant legs of martial arts athletes seem to have higher risk of cartilage degeneration due to the observed interlimb differences in T2 values.

Baseline-to-loaded changes in regional tibial cartilage thickness, T1ρ and T2: Utilization of an MRI compatible loading device.

The objective of the study was to evaluate tibial cartilage thickness (TCT), T1ρ and T2 values within both loaded and baseline configurations in a cadaveric knee model using a 3D bone based tibial coordinate system. Ten intact cadaveric knees were mounted into an magnetic resonance imaging (MRI) compatible loading device. Morphologic and quantitative MRI (qMRI) images were acquired with the knee in a baseline configuration and after application of 50% body weight. The morphologic images were evaluated for cartilage degeneration using a modified Noyes scoring system. A 3D bone-based tibial coordinate system was utilized to evaluate regional changes of tibial T1ρ, T2, and cartilage thickness values among regions covered and uncovered by the meniscus. Inter-regional differences in medial and lateral MRI outcomes were found between loaded and baseline configurations. Cartilage regions covered by the meniscus demonstrated disparate qMRI and TCT results as compared to cartilage regions not covered by the meniscus. The regions covered by meniscus experienced a ~3.5%, ~0.5%, and ~5.5% reduction of T1ρ (p < 0.05, medial and lateral compartments), T2 and TCT, respectively, in both compartments while regions not covered by the meniscus experienced larger reductions of ~10%, ~2%, and ~10.5% reduction of T1ρ (p < 0.05, medial and lateral compartments), T2 and TCT (p < 0.05, lateral compartment only), respectively, in both compartments. T1ρ and T2 decreases following application of 50% body weight load were substantially larger in the tibial regions with modified Noyes grade 3 (n = 2) compared to either healthy regions (n = 85, p < 0.0.003) or regions with modified Noyes grade 2 (n = 13, p < 0.004). Interregional differences in MRI outcomes reflect variations in structure and function, and largely followed a pattern in cartilage regions that were covered or not covered by the meniscus. Results of the current study suggest that ΔT1ρ and ΔT2 values may be sensitive to superficial fissuring, more than baseline or loaded T1ρ or T2 values, or TCT alone, however future studies with additional specimens, with greater variability in OA grade distribution, may further emphasize the current findings.

Clinical evaluation of 3D high-resolution isotropic knee MRI using Multi-Interleaved X-prepared TSE with inTUitive RElaxometry (MIXTURE) for simultaneous morphology and T2 mapping

PurposeQuantitative MRI techniques such as T2 mapping are useful in comprehensive evaluation of various pathologies of the knee joint yet require separate scans to conventional morphological measurements and long acquisition times. The recently introduced 3D MIXTURE (Multi-Interleaved X-prepared Turbo-Spin Echo with Intuitive Relaxometry) technique can obtain simultaneous morphologic and quantitative information of the knee joint. To compare MIXTURE with conventional methods and to identify differences in morphological and quantitative information. MethodsPhantom studies were conducted, and in vivo human scans were performed (20 patients) presented with knee arthralgia. MIXTURE is based on 3D TSE without and with T2 preparation modules in an interleaved manner for both morphology with PDW and fat suppressed T2W imaging as well as quantitative T2 mapping within one single scan. Image quality and lesion depiction were visually assessed and compared between MIXTURE and conventional 2D TSE by two experienced radiologists. Contrast-to-noise ratio was used to assess the adjacent tissue contrast in a quantitative way for both obtained PDW and fat suppressed T2W images. Quantitative T2 values were measured in phantom and from in vivo knee cartilage. ResultsThe overall diagnostic confidence and contrast-to-noise ratio were deemed comparable between MIXTURE and 2D TSE. While the chosen T2 preparation modules for MIXTURE rendered consistent T2 values comparing to the current standard, measured cartilage T2 values ranged from 26.1 to 50.7 ms, with significant difference between the lesion and normal areas (p < 0.05). ConclusionsMIXTURE can help to provide high-resolution information for both anatomical and pathological assessment.

Differences in running biomechanics and tibiotalar cartilage T2 relaxation time between runners with and without asymptomatic tibial sesamoid bone marrow edema – clinical case series

ABSTRACT The impact of asymptomatic bone marrow edema (BME) in sesamoids on running biomechanics remains largely unknown, but exploring this relationship could aid early detection of forefoot-related injuries with cost-effective modalities. This study aimed to compare the running biomechanics of runners with asymptomatic BME in the tibial sesamoids with that of healthy controls. Four runners with asymptomatic BME in tibial sesamoids and four healthy runners participated. Lower extremity joint kinetics and kinematics were assessed along with plantar pressure while running at a self-selected speed. The T2 relaxation time of the tibiotalar cartilage was measured using MRI-derived T2 maps. Compared to the non-injured group, the injured group exhibited significantly lower plantar pressure under the hallux (p = 0.001), increased peak ankle rotation angles (p = 0.025), reduced ankle power generation (p = 0.049), and increased knee extension torque (p = 0.015). No significant differences in T2 values of the tibiotalar cartilage were observed. It appears that runners with asymptomatic BME adapted their running strategies by modifying their ankle biomechanics and reducing plantar pressure, even in the absence of pain. While the precise implications of these biomechanical alterations warrant further investigation, this study provides valuable insights into the relationship between asymptomatic BME and running biomechanics.

Evaluation of articular cartilage degeneration in patients with osteonecrosis of the femoral head using T2 mapping magnetic resonance imaging.

To evaluate and characterise articular cartilage degeneration in patients with osteonecrosis of the femoral head (ONFH) using T2 mapping magnetic resonance imaging. We reviewed 35 patients with ONFH (20 males and 15 females, mean age: 45.7 ± 12.9 years) without obvious cartilage abnormalities on plain magnetic resonance imaging (ONFH group) and 25 healthy volunteers (9 males and 16 females, mean age: 42.9 ± 5.8 years) (control group). All patients underwent T2 mapping magnetic resonance imaging after ONFH onset. The region of interest was defined as the weight-bearing portion of the articular cartilage in the femoral head and acetabulum in the coronal view. The T2 values of the articular cartilage of the acetabulum and femoral head, including necrotic and normal regions, were significantly higher in the ONFH group than those in the control group. These T2 values of the acetabulum and femoral head in Stages 3A and 2 were significantly higher in the ONFH group than those in the control group. The articular cartilage of the acetabulum and femoral head can deteriorate after the onset of ONFH, which may affect the natural history of ONFH and ONFH treatment. Our findings suggest the need for early intervention in joint preservation surgery.

Evaluation of Open Versus Arthroscopic Anterior Talofibular Ligament Reconstruction for Chronic Lateral Ankle Instability With Talar and Subtalar Cartilage MRI T2 Mapping: A 3-Year Prospective Study.

Previous studies have examined patients with chronic lateral ankle instability (CLAI) undergoing open and arthroscopic anterior talofibular ligament (ATFL) reconstruction, reporting equivalent clinical results between the 2 procedures. However, data on the magnetic resonance imaging (MRI) outcomes on cartilage health after the 2 procedures are limited. To compare the cartilage MRI T2 values of the talar and subtalar joints between patients with CLAI undergoing open and arthroscopic ATFL reconstruction. Cohort study; Level of evidence, 3. A prospective study was conducted on patients who underwent open or arthroscopic ATFL reconstruction between January 2018 and December 2019, with a mean follow-up duration of 3 years. MRI scans and American Orthopaedic Foot & Ankle Society (AOFAS) and Tegner score estimations were completed by patients ≤1 week before surgery, as a baseline measurement, and at a 3-year follow-up. A total of 21 healthy volunteers were included who underwent MRI at baseline. Cartilage health was evaluated using MRI T2 mapping. The talar and subtalar cartilage regions were segmented into 14 subregions. At baseline, patients with CLAI had substantially higher T2 values in the medial anterior, medial center, medial posterior, and lateral center regions on the talus compared with the healthy controls (P = .009, .003, .001, and .025, respectively). Remarkable increases in T2 values in the lateral posterior region on the talus were observed from baseline to follow-up in the open group (P = .007). Furthermore, T2 values were considerably higher in the medial center, medial posterior, lateral posterior, and lateral posterior calcaneal facets of the posterior subtalar joint at follow-up in the arthroscopic group compared with the baseline values (P = .025, .002, .006, and .044, respectively). No obvious differences in ΔT2 values were noted between the 2 groups at follow-up. The AOFAS and Tegner scores remarkably improved from baseline to follow-up for the 2 groups (open: 3.25 ± 0.58 vs 5.13 ± 0.81, P < .001; arthroscopic: 3.11 ± 0.90 vs 5.11 ± 1.08, P < .001), with no considerable difference between them. The elevated T2 values of cartilage could not be fully recovered after open or arthroscopic ATFL reconstruction. Both arthroscopic and open ATFL reconstruction displayed similar effects on cartilage health concerning ΔT2, but the arthroscopic group demonstrated more degenerative cartilage subregions than the open group.

T2 mapping for quantitative assessment of ankle cartilage of weightlifters

The research into the prevention of sports injuries among the population, particularly juveniles, has become crucial due to the increasing participation in physical exercises like fitness. To assess the difference in T2 values of ankle talar cartilage between weightlifters and healthy volunteers using quantitative magnetic resonance imaging (MRI) technique T2 mapping. Study design: Prospective. Prospective evaluation of T2 values of ankle cartilage of 50 weightlifters (30 adults and 20 juveniles) and 100 healthy volunteers (80 adults and 20 juveniles) using Siemens 3.0 T MRI with PDWI, T1WI, and T2 mapping sequences. Three physicians manually divided the talar cartilage of the ankle joint into six regions of interest. Three physicians utilized the anterior and posterior cut edges of the tibial cartilage as markers to identify the corresponding anterior and posterior cut edges of the talar cartilage on the sagittal MRI images. The medial and lateral sides were defined as half of the talar articular surface on the coronal plane. Differences in T2 values in each cartilage region were compared using independent sample T test or Mann–Whitney U test. The T2 values of talar cartilage were significantly increased in the athlete group relative to the volunteer group (35.11 and 31.99, P < 0.001), with the most significant difference observed in the juvenile athlete group compared to the volunteer group (34.42 and 28.73, P < 0.001). There was a significant difference in the T2 value of ankle talar cartilage between weightlifters and healthy volunteers, and juveniles may be more vulnerable to overuse sports injuries. This study contributes to understanding the cartilage health of juvenile athletes and the prevention of sports injuries.

Difference in quantitative MRI measurements of cartilage between Wiberg type III patella and stable patella based on a 3.0-T synthetic MRI sequence

PurposeThe purpose of this study was to investigate the difference between the quantitative MRI values of Wiberg type III and stable patellar cartilage, and to improve the accuracy of MRI quantification in early patellar cartilage damage. MethodsThe knee joints of 94 healthy volunteers were scanned by a GE Signa Pioneer 3.0-T synthetic MRI machine. According to the Wiberg classification, the patella was divided into types I-III. Types I-II made up the stable patella group, and type III made up the unstable patella group. Two radiologists independently measured patellar cartilage thickness and quantitative synthetic MRI values (T1, T2, PD) in both groups. Interobserver agreement for quantitative variables was assessed using the BlandAltman method. A third radiologist assessed differences in measurements. ResultsThe medial T2 and T1 value of Wiberg III patella did not show a normal distribution (all P > 0.05). Compared with the stable group, the Wiberg type III group had thinner cartilage of the medial surface of the patella (P < 0.05), lower cartilage T2 and PD values (P < 0.05), but a similar cartilage T1 value (P > 0.05). There was no significant difference in the cartilage thickness, T1, T2, or PD value of the lateral patella between the Wiberg type III and the stable group (P > 0.05). ConclusionThere were certain differences in the cartilage thickness of the medial surface of the patella and the quantitative value of synthetic MRI in Wiberg type III patellas. Quantitative studies of patellar cartilage MRI measurements need to consider the influence of patellar morphology.

Assessment of articular cartilage of ankle joint in stable and unstable unilateral weber type-B/SER-type ankle fractures shortly after trauma using T2 relaxation time.

Early detection of post-traumatic cartilage damage in the ankle joint in magnetic resonance images can be difficult due to disturbances to structures usually appearing over time. To study the articular cartilage of unilateral Weber type-B/SER-type ankle fractures shortly post-trauma using T2 relaxation time. Fifty one fractured ankles were gathered from consecutively screened patients, compiled initially for RCT studies, and treated at Oulu University Hospital and classified as stable (n = 28) and unstable fractures (n = 23) based on external-rotation stress test: medial clear space of ≥5mm was interpreted as unstable. A control group of healthy young individuals (n = 19) was also gathered. All ankles were imaged on average 9 (range: 1 to 25) days after injury on a 3.0T MRI unit for T2 relaxation time assessment, and the cartilage was divided into sub-regions for comparison. Control group displayed significantly higher T2 values in tibial cartilage compared to stable (six out of nine regions, p-values = .003-.043) and unstable (six out of nine regions, p-values = .001-.037) ankle fractures. No differences were detected in talar cartilage. Also, no differences were observed between stable and unstable fractures in tibial or talar cartilage. Lower T2 relaxation times of tibial cartilage in fractured ankles suggest intact extra cellular matrix (ECM) of the cartilage. Severity of the ankle fracture, measured by ankle stability, does not seem to increase ECM degradation immediately after trauma.

Improved accuracy and precision of fat-suppressed isotropic 3D T2 mapping MRI of the knee with dictionary fitting and patch-based denoising

PurposeTo develop an isotropic three-dimensional (3D) T2 mapping technique for the quantitative assessment of the composition of knee cartilage with high accuracy and precision.MethodsA T2-prepared water-selective isotropic 3D gradient-echo pulse sequence was used to generate four images at 3 T. These were used for three T2 map reconstructions: standard images with an analytical T2 fit (AnT2Fit); standard images with a dictionary-based T2 fit (DictT2Fit); and patch-based-denoised images with a dictionary-based T2 fit (DenDictT2Fit). The accuracy of the three techniques was first optimized in a phantom study against spin-echo imaging, after which knee cartilage T2 values and coefficients of variation (CoV) were assessed in ten subjects in order to establish accuracy and precision in vivo. Data given as mean ± standard deviation.ResultsAfter optimization in the phantom, whole-knee cartilage T2 values of the healthy volunteers were 26.6 ± 1.6 ms (AnT2Fit), 42.8 ± 1.8 ms (DictT2Fit, p < 0.001 versus AnT2Fit), and 40.4 ± 1.7 ms (DenDictT2Fit, p = 0.009 versus DictT2Fit). The whole-knee T2 CoV reduced from 51.5% ± 5.6% to 30.5 ± 2.4 and finally to 13.1 ± 1.3%, respectively (p < 0.001 between all). The DictT2Fit improved the data reconstruction time: 48.7 ± 11.3 min (AnT2Fit) versus 7.3 ± 0.7 min (DictT2Fit, p < 0.001). Very small focal lesions were observed in maps generated with DenDictT2Fit.ConclusionsImproved accuracy and precision for isotropic 3D T2 mapping of knee cartilage were demonstrated by using patch-based image denoising and dictionary-based reconstruction.Key points• Dictionary T2 fitting improves the accuracy of three-dimensional (3D) knee T2 mapping.• Patch-based denoising results in high precision in 3D knee T2 mapping.• Isotropic 3D knee T2 mapping enables the visualization of small anatomical details.

MRI-based T1rho and T2 cartilage compositional imaging in osteoarthritis: what have we learned and what is needed to apply it clinically and in a trial setting?

Cartilage MRI-based T1rho and T2 compositional measurements have been developed to characterize cartilage matrix quality and diagnose cartilage damage before irreversible defects are found, allowing intervention at an early, potentially reversible disease stage. Over the last 2 decades, this technology was investigated in numerous studies and was validated using specimen studies and arthroscopy; and longitudinal studies documented its ability to predict progression of degenerative disease and radiographic osteoarthritis (OA). While T1rho and T2 measurements have shown promise in early disease stages, several hurdles have been encountered to apply this technology clinically. These include (i) challenges with cartilage segmentation, (ii) long image acquisition times, (iii) a lack of standardization of imaging, and (iv) an absence of reference databases and definitions of abnormal cut-off values. Progress has been made by developing deep-learning based automatic cartilage segmentation and faster imaging methods, enabling the feasibility of T1rho and T2 imaging for clinical and scientific trial applications. Also, the Radiological Society of North America (RSNA) Quantitative Imaging Biomarker Alliance mechanism was used to establish standardized profiles for compositional T1rho and T2 imaging, and multi-center feasibility testing is work in progress. The last hurdles are the development of reference databases and establishing a definition of normal versus abnormal cartilage T1rho and T2 values. Finally, effective treatments for prevention and slowing progression of OA are required in order to establish T1rho and T2 as imaging biomarkers for initiating and monitoring therapies, analogous to the role of dual X-ray absorptiometry (DXA) bone mineral density measurements in the management of osteoporosis. KEY POINTS: • T1rho and T2 cartilage measurements have been validated in characterizing cartilage degenerative change using histology and arthroscopy as a reference. • They have also been shown to predict progression of cartilage degeneration and incidence of radiographic OA. • Advances have been made to facilitate clinical and trial application of T1rho and T2 by improved standardization of imaging and by establishing deep learning-based automatic cartilage segmentation. • Effective treatments with disease-modifying OA specific drugs may establish T1rho and T2 cartilage compositional measurements as biomarkers to initiate and monitor treatment.

Degenerative changes through MR cartilage mapping in anterior cruciate ligament-reconstructed knees

BackgroundAnterior cruciate ligament (ACL) injury increases risk for post traumatic knee osteoarthritis. ACL injury causes lack of knee stability and frequently requires ACL-reconstruction (ACLR) in order to restore functional and anatomical joint stability. Magnetic resonance imaging with T2 mapping sequence is used to quantify the amount of water content in articular cartilage hence; it is considered a better tool and more beneficial than radiographic based assessment in early detection even before being symptomatic. The aim of work is to estimate the incidence of subclinical degenerative changes that happened early in patients who underwent ACL reconstruction and to identify the correlations of T2 mapping values with patients' BMI, meniscal state/operations, ACL graft assessment and presence of ACLR related complications.ResultsThe study was conducted upon 71 patients, divided into 61 anterior cruciate ligament reconstructed knees and 10 control cases using 1.5 T MRI. Assessment of cartilage sub-compartment T2 values and comparison with average normal cartilage T2 values obtained from the control group. Multiple correlations of the grade of articular cartilage degeneration within anterior cruciate ligament reconstructed knees with Body Mass Index (BMI), time of operation as well associated meniscal operations and anterior cruciate ligament graft complications.ConclusionsAdding the T2 cartilage mapping sequence improves the ability to detect subclinical early degenerative articular cartilage changes in patients who underwent anterior cruciate ligament reconstruction, taking into consideration the relation of the patients' BMI, previous meniscal injuries/operation, ACL graft status and related graft complications with the T2 cartilage mapping values.

Clinical evaluation of platelet-rich plasma in the treatment of early and middle stage knee osteoarthritis under 3.0T MRI T2 mapping sequence

Objective: To quantitatively evaluate the clinical effect of platelet-rich plasma(PRP) intra-articular injection for early and middle stage knee osteoarthritis(KOA) treatment by 3.0T MRI T2 mapping sequence. Methods: Clinical data of 26 patients with early or middle stage KOA who received treatment from April to December 2021 at Department of Orthopaedic Surgery,the Second Affiliated Hospital,Zhengzhou University were retrospectively analyzed. In total, 8 patients were male and 18 were female,with age of (66.4±12.0)years(range:51 to 94 years). Four patients were bilateral KOA and 22 patients were unilateral KOA.All patients received PRP intra-articular injection. Patients underwent 3.0T MRI T2 mapping sequence scanning pre-treatment,3-month-after and 6-month-after treatment respectively. Those were used to measure and compare T2 values of medial and lateral femoral articular surface and patellofemoral articular surface. Visual analogue scale(VAS) and Western Ontario and McMaster Osteoarthritis Index (WOMAC) score were recorded and evaluated. The results were analyzed using repeated measure ANOVA followed by Bonferroni multiple comparison test.The correlation between WOMAC scores and T2 values at pre-treatment and 6 months post-treatment was analyzed using Pearson correlation test. Results: After treatment, the patients' International Cartilage Regeneration＆Joint Preservation Society(ICRS) classification were partly improved(one case improved from grade Ⅲ to grade Ⅱ, one case improved from grade Ⅱ to grade Ⅰ),and all patients generally improved after treatment in clinical symptoms. Compared with pre-treatment,VAS and WOMAC scores of grade Ⅰ,Ⅱ,and Ⅲ of 6-month after treatment were declined significantly(all P<0.05).The T2 values of articular cartilage declined to varying degrees(the decrease in T2 values was about 2.06 ms in grade Ⅰ, 2.66 ms in grade Ⅱ, and 3.72 ms in grade Ⅲ).Three-month (VAS:4.8±1.3,WOMAC:21.5±4.0) and 6-month (VAS:4.2±1.4,WOMAC:17.2±2.9) after treatment, the VAS and WOMAC score were significantly higher than those before treatment (VAS:6.0±1.2, WOMAC:29.0±2.3) (F=48.846, F=346.746;both P<0.01). Multiple comparisons showed a statistically significant difference between pre-treatment and post-treatment VAS (P<0.01) and it also was significantly different between 3-month and 6-month post-treatment (P<0.01).At 3- and 6-month after treatment,WOMAC scores were significantly different from before treatment.And it also was significantly different between 3-month and 6-month post-treatment (P<0.01).There was a statistically significant improvement in T2 values of patellofemoral articular surface, medial and lateral femoral articular surface at pre-treatment((44.64±4.02)ms,(44.17±3.64)ms and(43.53±3.91)ms) and 3-month ((43.19±3.91)ms,(43.24±3.34)ms and (42.47±3.80)ms), 6-month ((41.49±3.64)ms,(41.83±3.15)ms and (41.10±3.42)ms) after treatment(F=148.845,F=73.657,F=86.268;all P<0.01).The results of the multiple comparisons showed a statistically significant difference in the T2 values of medial and lateral femoral articular surface and patellofemoral articular surface at each time point(all P<0.01).The Pearson correlation analysis suggested that the WOMAC score at pre-treatment was positively correlated with the medial condyle (r=0.856,P<0.01) and the patellofemoral joint surface T2 values (r=0.840,P<0.01);The WOMAC score at 6-month post-treatment was positively correlated with the medial condyle (r=0.731,P<0.01) and the patellofemoral joint surface T2 values (r=0.691,P<0.01). Conclusions: In the treatment of early and mid-stage KOA,MRI T2 mapping sequences are able to indicate the integrity of cartilage morphology and quantitatively evaluate cartilage repair. PRP has a good therapeutic effect on cartilage repair and reconstruction.

Nonextruded Grafts Result in Better Cartilage Quality After Lateral Meniscal Allograft Transplantation: Quantitative 3-T MRI T2 Mapping

Background: Several studies have reported that graft extrusion after meniscal allograft transplantation (MAT) is associated with deterioration of surgical outcomes. However, no study has investigated the effect of graft extrusion on the articular cartilage using objective quantitative methods. Purpose/Hypothesis: This study aimed to investigate the influence of graft extrusion on the chondroprotective effect of lateral MAT on knee articular cartilage. We hypothesized that MAT without graft extrusion would result in better cartilage quality than MAT with graft extrusion. Study Design: Cohort study; Level of evidence, 3. Methods: Altogether, 105 patients who underwent isolated lateral MAT were divided into the extrusion and nonextrusion groups based on postoperative 3-month magnetic resonance imaging. Quantitative T2 mapping was performed on pre- and postoperative magnetic resonance imaging at midterm follow-up (mean ± SD, 3.2 ± 0.7 years). The weightbearing area of the femoral and tibial plateau articular cartilage was divided into 6 segments (F1, F2, F3, TP1, TP2, and TP3) from the anterior to posterior direction according to the meniscal coverage area. Each segment was further segmented into superficial and deep layers for zonal analysis. Longitudinal change in cartilage T2 value was compared between the groups. Lysholm scores were used to evaluate clinical function. Results: The mean T2 value of the nonextrusion group showed a significant improvement in 14 of 18 segments after lateral MAT, whereas the extrusion group demonstrated no statistically significant change. The biochemical properties of cartilage tissue as judged by quantitative T2 mapping indicated improvement in the nonextrusion group as compared with the extrusion group in the F2, TP2, and TP3 segments overall; the deep layers of the F1, F2, and TP2 segments; and the superficial layer of the TP3 segment (P < .05). Conclusion: This study shows that the nonextruded graft results in better cartilage properties of the knee joint after lateral MAT as compared with the extruded graft at midterm follow-up.

Quantitative MRI evaluation of articular cartilage in patients with meniscus tear.

PurposeThe aim of this study was to assess quantitatively articular cartilage volume, thickness, and T2 value alterations in meniscus tear patients.Materials and methodsThe study included 32 patients with meniscus tears (17 females, 15 males; mean age: 40.16 ± 11.85 years) and 24 healthy controls (12 females; 12 males; mean age: 36 ± 9.14 years). All subjects were examined by 3 T magnetic resonance imaging (MRI) with 3D dual-echo steady-state (DESS) and T2 mapping images. All patients underwent diagnostic arthroscopy and treatment. Cartilage thickness, cartilage volume and T2 values of 21 subregions of knee cartilage were measured using the prototype KneeCaP software (version 2.1; Siemens Healthcare, Erlangen, Germany). Mann-Whitney-U tests were utilized to determine if there were any significant differences among subregional articular cartilage volume, thickness and T2 value between patients with meniscus tear and the control group.ResultsThe articular cartilage T2 values in all subregions of the femur and tibia in the meniscus tear group were significantly higher (p< 0.05) than in the healthy control group. The cartilage thickness of the femoral condyle medial, femur trochlea, femur condyle lateral central, tibia plateau medial anterior and patella facet medial inferior in the meniscus tear group were slightly higher than in the control group (p< 0.05). In the femur trochlea medial, patella facet medial inferior, tibia plateau lateral posterior and tibia plateau lateral central, there were significant differences in relative cartilage volume percentage between the meniscus tear group and the healthy control group (p< 0.05). Nineteen patients had no cartilage abnormalities (Grade 0) in the meniscus tear group, as confirmed by arthroscopic surgery, and their T2 values in most subregions were significantly higher (p< 0.05) than those of the healthy control group.ConclusionThe difference in articular cartilage indexes between patients with meniscus tears and healthy people without such tears can be detected by using quantitative MRI. Quantitative T2 values enable early and sensitive detection of early cartilage lesions.

Paper 01: ACL Reconstructed Knees Had Significantly Higher MR T1ρ and T2 Values in Cartilage but not in Meniscus Compared to Contralateral Knees at 10 Years after ACL Reconstruction

Paper 01: ACL Reconstructed Knees Had Significantly Higher MR T1ρ and T2 Values in Cartilage but not in Meniscus Compared to Contralateral Knees at 10 Years after ACL Reconstruction

Role of MRI and T2 mapping in osteoarthritis of knee joint

Introduction: osteoarthritis is the most common joint disease and the leading cause of long-term disability, placing tremendous financial burdens at the individual and societal levels. Indeed, the onset of biochemical changes leading to irreversible cartilage loss. Objective: to clarify the role of conventional MRI anT2 mapping in patients with osteoarthritis of knee joint. Materials and methods: This prospective study was conducted between June 2019 and July 2021, on 40 cases; 30 patients clinically presented with knee pain and 10 healthy volunteers as a control group. They were referred from outpatient clinics and orthopedic surgery department to Radio-diagnosis and Medical Imaging Department of Tanta university hospitals for assessment by MRI. This study was approved by the ethics committee of Tanta University. Results: The mean and standard deviation for T2 values of cartilage that measured at 4 compartments of the knee joint were elevated in patients clinically suspected to have osteoarthritic changes than healthy volunteers with statistically significant P values (&lt;0.001) at 4 compartments. Conclusions: MRI is a powerful non-invasive tool for both diagnosis and characterization of cartilage degeneration.

Analysis of Knee Joint Injury Caused by Physical Training of Freshmen Students Based on 3T MRI and Automatic Cartilage Segmentation Technology: A Prospective Study.

BackgroundThe differential effects of various exercises on knee joint injury have not been well documented. Improper physical training can cause irreversible damage to the knee joint. MRI is generally used to precisely analyze morphological and biochemical changes in the knee cartilage. We compared the effects of long-walking and regular daily physical training on acute and chronic knee joint injuries as well as cartilage structure in freshmen students.MethodsA total of 23 young male college freshmen were recruited to participate in an 8-day 240 km long distance walk and a one-year daily training. 3D-DESSwe, 2D T2 mapping, DIXON, and T1WI of the right knee joint were performed using the MAGNETOM Spectra 3T MR scanner. The injury of meniscus, bone marrow edema, ligaments and joint effusion is graded. Cartilage volume, thickness and T2 values of 21 sub-regions of the knee cartilage were estimated using automatic cartilage segmentation prototype software. Friedman’s test and Wilcoxon paired rank-sum test were used to compare quantitative indices of knee cartilage in three groups.ResultsThe injury to the medial meniscus and anterior cruciate ligament of the knee joint, joint effusion, and bone marrow edema was significantly higher in the long-walking group compared to the baseline and daily groups. Furthermore, injury to the lateral meniscus was significantly worse in the long-walking group compared to the baseline group but was significantly better in the daily group compared to the baseline group. No significant changes to the posterior cruciate ligament were observed among the three groups. Knee cartilage volume was significantly increased, mainly in the stress surface of the femur, patella, and the lateral area of the tibial plateau. Regular daily training did not significantly change the thickness of the knee cartilage. Conversely, knee cartilage thickness decreased in the long-walking group, especially in the medial and lateral areas of the femur and tibial plateau. Moreover, no significant changes were observed in the knee cartilage volume of the long-walking group. Both long-walking and daily groups showed reduced T2 values of the knee joint compared to the baseline.ConclusionAmong freshmen students and the training of this experimental intensity, our results show that regular daily training does not cause high-level injury to the knee joint, but improve the knee joint function adaptability by increasing cartilage volume. Moreover, knee injury caused by short-term long walking can be reversible.

T2 MAPPING OF THE ARTICULAR CARTILAGE AS A BIOMARKER FOR OA IN A POPULATION BASED COHORT: THE ROTTERDAM STUDY

While quantitative T2 mapping has been well established as a non-invasive tool for assessing (early) OA progression, there have been a limited number of studies investigating this in large population-based cohorts, other than the OAI. The objectives of the current study were to evaluate 1) the relationship between T2 relaxation times and patient characteristics age and BMI, and 2) the relationship between T2 relaxation times and MRI-based OA status, in a population-based study. We included 1327 knees from 665 females (mean age 59.8 years;SD:3.7 and mean BMI 26.9 kg/m2; SD:4.7) from a subcohort of the population based Rotterdam Study. All knees underwent 1.5 Tesla MRI at two different time-points (mean time between scans 5.1 years; SD: 0.4) comprising sagittal dual-echo FSE proton density–weighted, spoiled gradient echo with fat suppression, and fast imaging employing steady-state acquisition (FIESTA) sequences. The second time-point included an additional sagittal T2-weighted FSE sequence with fat suppression (4 echo times (15, 30, 45, 60 ms), repetition time 4100ms, field of view 160 x 160mm; slice thickness 3.2mm; matrix 256 x 256) for the purpose of T2 mapping. T2 relaxation times were calculated in six femoral and tibial regions of interest of full-thickness tibiofemoral cartilage: LF, LT, pLF, MF, MT, and pMF. Differences between groups were calculated using Student's t-tests for continuous data. Associations between T2 relaxation times and MRI Osteoarthritis Knee Score (MOAKS)-based tibiofemoral OA were analyzed using logistic regression with age and BMI adjustments. We defined early OA as OA developed between time-points, and late OA as OA established at the first time-point, prior to T2 mapping sequencing. Statistical analyses were performed using R (version 3.6.3). One hundred thirty-six knees had MRI defined OA at baseline, and 235 knees had OA at follow-up, meaning 99 knees developed OA the follow-up. T2 relaxation times were positively correlated with BMI, which was most pronounced in the lateral compartment (R 2 range: 0.38-0.44, all p-values <0.001). Very weak associations were found between T2 relaxation times and age for both compartments (R 2 range: 0.01-0.08). Knees with OA at follow-up had higher T2 values compared to knees without OA in the LF weight-bearing cartilage (35.7 vs. 35.3 ms, p=0.04), LT weight-bearing cartilage (35.8 vs. 34.8 ms, p<0.001), pLF cartilage (37 vs. 35.6 ms, p<0.001), MT weight-bearing cartilage (35.1 vs. 34.7, p=0.02), and pMF cartilage (37.9 vs. 36.9 ms, p<0.001). At the first time-point the LT (OR:1.11; 95%CI:1.04-1.18), pLF (OR:1.32; 95%CI:1.21-1.45), MF (OR:1.12; 95%CI:1.03-1.22), MT (OR:1.12; 95%CI:1.02-1.22), and pMF (OR:1.18; 95%CI:1.08-1.29) cartilage were significantly associated with OA after adjustments. At follow-up, LT (OR:1.08; 95%CI: 1.02-1.14), pLF (OR:1.27; 95%CI: 1.18-1.37) and pMF (OR:1.17; 95%CI:1.09-1.26) were associated with OA. In knees that developed OA during follow-up, T2 values of the pLF cartilage (OR:1.16; 95%CI:1.04-1.29) were associated with OA development. In this population-based cohort, early OA was associated with T2 values of the pLF, whereas advanced OA was associated with LT, pLF, MF, MT, and pMF cartilage segments. T2 values had very weak correlations with age, whereas weak to moderate correlations were observed between T2 relaxation values and BMI. none none. The authors are grateful to the participants and staff of the Rotterdam Study CORRESPONDENCE ADDRESS: e.oei@erasmusmc.nl