Related Experiment Video
Updated: Jan 31, 2026

Tissue Collection and RNA Extraction from the Human Osteoarthritic Knee Joint
Published on: July 22, 2021
Biexponential T1ρ relaxation mapping of human knee menisci
Rahman Baboli1, Azadeh Sharafi1, Gregory Chang1
1From the Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York, USA.
Background:
Measuring T1ρ in the knee menisci can potentially be used as noninvasive biomarkers in detecting early-stage osteoarthritis (OA).
Purpose:
To demonstrate the feasibility of biexponential T1ρ relaxation mapping of human knee menisci.
Study Type:
Prospective.
Population:
Eight healthy volunteers with no known inflammation, trauma, or pain in the knee and three symptomatic subjects with early knee OA.
Field Strength/Sequence:
Customized Turbo-FLASH sequence to acquire 3D-T1ρ -weighted images on a 3 T MRI scanner.
Assessment:
T1ρ relaxation values were assessed in 11 meniscal regions of interest (ROIs) using monoexponential and biexponential models.
Statistical Tests:
Nonparametric rank-sum tests, Kruskal-Wallis test, and coefficient of variation.
Results:
The mean monoexponential T1ρ relaxation in the lateral menisci were 28.05 ± 4.2 msec and 37.06 ± 10.64 msec for healthy subjects and early knee OA patients, respectively, while the short and long components were 8.07 ± 0.5 msec and 72.35 ± 3.2 msec for healthy subjects and 2.63 ± 2.99 msec and 55.27 ± 24.76 msec for early knee OA patients, respectively. The mean monoexponential T1ρ relaxation in the medial menisci were 34.30 ± 3.8 msec and 37.26 ± 11.38 msec for healthy and OA patients, respectively, while the short and long components were 7.76 ± 0.7 msec and 72.19 ± 4.2 msec for healthy subjects and 3.06 ± 3.24 msec and 55.27 ± 24.59 msec for OA patients, respectively. Statistically significant (P ≤ 0.05) differences were observed in the monoexponential relaxation between some of the ROIs. The T1ρ,short was significantly lower (P = 0.02) in the patients than controls. The rmsCV% ranges were 1.51-16.6%, 3.59-14.3%, and 4.91-15.6% for T1ρ -mono, T1ρ -short, and T1ρ -long, respectively.
Data Conclusion:
Our results showed that in all ROIs, T1ρ relaxation times of outer zones (red zones) were less than inner zones (white zones). Monoexponential T1ρ was increased in medial, lateral, and body menisci of early OA while the biexponential numbers were decreased in early OA patients.
Level Of Evidence:
2 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019. J. Magn. Reson. Imaging 2019;50:824-835.
Related Concept Videos
Knee Joint
A total of seven ligaments support the knee joint. The patellar ligament, which is also attached to the quadriceps femoris...
Relaxation of Skeletal Muscles
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open....
Classification of Skeletal Muscle Relaxants
Peripherally acting skeletal muscle relaxants interfere with the neurotransmission at the neuromuscular end plate to induce paralysis during...
Skeletal Muscle Relaxants: Therapeutic Uses
Skeletal Muscle Relaxants: Adverse Effects
Unlike...
Centrally Acting Muscle Relaxants: Therapeutic Uses
Centrally acting drugs are classified into spasmolytic and antispasmodic drugs. Spasmolytic drugs such as baclofen, diazepam, and tizanidine inhibit spinal motor neurons and decrease muscle tone. Spasmolytic drugs are administered for severe and chronic spasms due to multiple sclerosis, cerebral palsy, stroke, and spinal cord and muscle injuries. However,...

