Table 2.
Main characteristics of representative studies investigating novel MRI techniques for knee osteoarthritis.
| Authors | Country | Aim/Rationale | Patients | MRI | Sequence | Main conclusion |
|---|---|---|---|---|---|---|
| H. Nishioka et al. [36] | Kumamoto, Japan | To perform qualitative evaluations of reparative tissue on articular surface of medial compartment after HCO with MRI T1ρ and T2 mapping | 20 | 3 T scanner (Philips Healthcare, Best, The Netherlands) | T1ρ-WI T2-WI |
T1ρ and T2 mapping revealed that the repaired tissue was fibrocartilage |
| Robert Stahl et al. [29] | San Francisco, USA | To evaluate the diagnostic value of T2 and T1ρ in identifying focal cartlage lesions in asymptomatic physically active subjects | 37 | 3 T scanner (Signa, GE Medical Systems, Waukesha, WI) | T1ρ-WI T2-WI |
T1ρ and T2 imaging demonstrated a different cartilage composition in active subjects with and without focal cartilage abnormalities |
| Hajimu Goto et al. [38] | Kobe, Japan | To investigate effect of aging and weight-bearing on T1ρ values in cartilage | 32 | 3 T scanner (Philips Healthcare, Best, The Netherlands) | T1ρ-WI | The degree of weight-bearing and, in particular aging, correlate with changes in cartilage T1rho values |
| Timothy C. Dunn et al. [21] | San Francisco, USA | To determine differences in T2 values in femoral and tibial cartilage in patients with varying degrees of OA | 55 | 1.5 T scanner (GE Medical Systems, Milwaukee, Wis) | T2-WI | T2 values of femoral and medial tibial cartilage increase with the severity of OA |
| M. F. Koff et al. [18] | Rochester, USA | To study T2 values of patellar cartilage grouped by radiographic stage of patello-femoral OA and by BMI | 113 | 1.5 T scanner (Signa, GE Medical Systems, Waukesha, WI) | T2-WI | T2 values are not sensitive to changes in radiographic stages of OA and BMI could be considered a factor for a potential increase of T2 values |
| Ping Zhang et al. [41] | Shijiazhuang, China | To study effects of long-distance running on knee cartilage with T2*-WI | 12 | 3 T scanner (Magnetom; Siemens Healthcare, Erlangen, Germany) | T2*-WI | An increase in T2* values of knee cartilage happened right after long distance running with a following reduction in the 2 months later |
| Ashley A. Williams et al. [42] | California, USA | To evaluate with UTE-T2* relationship between cartilage chenges, knee function, pain and gait metrics, 2 years after ACLR | 60 | 3 T scanner (Signa, GE Medical Systems, Waukesha, WI) | UTE-T2* | Patellofemoral deep cartilage matrix disruption, as assessed by MRI UTE-T2*, was associated with reduced sports and recreational function and with gait metrics reflective of altered patellofemoral loading |
| Taku Ukai et al. [43] | Kanagawa, Japan | To measure damaged areas of cartilage with ADC, T2 values and FA | 41 | 3 T scanner (Achieva 3 Tesla, Philips Healthcare, Best, The Netherlands) | ADC FA T2-WI |
T2 mapping is useful for detecting moderate or severe cartilage damage. ADC can be used to detect early stage cartilage damage, FA can also distinguish normal from damaged cartilage |
| S. T. Soellner et al. [48] | Erlangen, Germany | To compare gagCEST of knee cartilage with intraoperative results for the assessment of early OA and to define gagCEST values for the differentiation between healthy and degenerated cartilage | 21 | 3 T scanner (Signa, GE Medical Systems, Waukesha, WI) | gagCEST | gagCEST might provide a diagnostic tool for the detection of early knee-joint cartilage damage and grading |
| Stine Hangaard et al. [49] | Copenhagen, Denmark | To evaluate changes in quality of cartilage after weight loss | 19 | 1.5 T scanner (Philips Healthcare, Best, The Netherlands) | dGEMRIC | Improvement of cartilage quality, assessed with dGEMRIC, after weight loss might be possible only in early stage of KOA |
| Guillaume Madelin et al. [46] | New York, USA | To evaluate the potential of sodium MRI to detect changes over time of apparent sodium concentration (ASC) in articular cartilage in patients with KOA | 12 | 7 T scanner (Siemens Healthcare, Erlangen, Germany) | 23Na+-MRI | Quantitative sodium MRI has the potential to detect a decrease of ASC over time in articular cartilage of patients with KOA |
23Na-MRI, sodium magnetic resonance imaging; ADC, apparent diffusion coefficient; DTI, diffusion tensor imaging; BMI, body mass index; dGEMRIC, delayed gadolinium-enhanced MRI of cartilage; DWI, diffusion-weighted imaging; FA, fractional anisotropy; GAG, glycosaminoglycan; GagCEST, GAG chemical exchange saturation transfer; HCO, hemicallotasis osteotomy; KOA, knee osteoarthritis; MRS, magnetic resonance spectroscopy; MTR, magnetization ratio; OA, osteoarthritis; TE, time to echo; UTE, ultrashort echo time; WI, weighted imaging.