Value of 3.0T MRI T2 mapping combined with SWI for the assessment of early lesions in hemophilic arthropathy

Figures & data

Table 1. MR parameters.

Pulse	Repetition	Echo time	Section thickness	Gap	Matrix	Field of view	No. of signals acquired
Sequence	time (ms)	(ms)	(mm)	(mm)	(-)	(cm)	(time)
T1WI	310	11	4	0.6	384 × 268	18 × 18	1
PDWI	4200	36	4	0.6	320 × 224	18 × 18	1
3D-DESS	14.1	5	1.2	0.12	256 × 256	16 × 16	1
T2 mapping	1950	13.8 with eight echoes	4	0.8	320 × 192	16 × 16	1
SWI	28	5	1	0.2	256 × 192	16 × 16	1

Figure 1. Healthy volunteer male 10 years old. (A) 3D-DESS image shows intact articular cartilage morphology of the medial femoral condyle of the left knee with a smooth surface and no obvious signal abnormality. (B) The T2 mapping pseudo-color image shows uniform distribution of cartilage color scale and intact articular surface distribution. (C) MRI SWI image shows intact articular cartilage morphology with a smooth surface and no magnetic sensitive low signal shadow in the joint space.

Figure 3. Hemophilic arthropathy Experimental group A Male 9 years old. (A) The 3D-DESS image showed intact articular cartilage morphology of the medial femoral condyle of the right knee joint with no obvious signal abnormalities. (B) T2 mapping pseudo-color image showing an uneven distribution of cartilage color scale, uneven color scale in the weight-bearing area of articular cartilage with a small amount of red-yellow scale, and significantly elevated cartilage T2 value. (C) MRI SWI showing a small amount of hemosiderin on the anterior-posterior border of the articular suprapatellar capsule and femoral cartilage. The MRI SWI shows a small amount of iron-containing hematoxylin in the suprapatellar capsule and the anterior-posterior border of the femoral cartilage.

Figure 4. Patient with hemophilic arthropathy Experimental group B Male 11 years old. SWI showing a large amount of iron deposition with hemosiderin at the anterior-posterior border of the suprapatellar capsule and femoral cartilage.

Figure 2. A bar graph showing T2 values for the different regions of interest (ROIs) in the knee. Groups HC (control), A (International Cartilage Repair Society [ICRS] level 0 and I), and B (ICRS levels II and III) were compared for each ROI. * means statistically significant (P < 0.05).

Table 2. Comparative results of articular cartilage T2 values in the control group, experimental group A, and experimental group B (x¯±s, ms).

Cartilage zoning	Control group	Experimental group A	Experimental group B	F		P
					Control vs. Group A	Control vs. Group B	Group A vs. Group B
Patella	39.30 ± 4.00	43.49 ± 5.44	40.76 ± 3.79	6.95	0.002	0.400	0.070
Lateral Femoral Condyles	48.12 ± 4.45	51.16 ± 5.96	49.01 ± 4.69	2.30	0.020	0.025	0.012
Medial femoral condyle	47.36 ± 6.60	52.06 ± 8.26	46.96 ± 6.03	4.43	0.010	0.007	0.030
Lateral tibial condyle	38.40 ± 5.60	42.39 ± 6.68	40.77 ± 5.60	4.14	0.005	0.040	0.041
Medial tibial condyle	40.30 ± 5.02	43.60 ± 6.93	38.57 ± 4.45	4.68	0.023	0.036	0.010