The features of cerebral permeability and perfusion detected by dynamic contrast-enhanced magnetic resonance imaging with Patlak model in relapsing–remitting multiple sclerosis

Figures & data

Figure 1 The time-concentration curves (left) and schematic diagram of the Patlak model (right).

Abbreviations: K^trans, volume transfer constant; V_p, fractional plasma volume.

Figure 2 The representative images of dynamic contrast-enhanced magnetic resonance imaging with Patlak model.

Notes: A 24-year-old patient with RRMS. (A) Precontrast T1-weighted: round low signal in the left periventricular areas (arrow). (B) Dynamic contrast-enhanced T1-weighted images: the lesion was enhanced in T1-weighted contrast-enhanced sequences (arrow). (C) K^trans map. (D) V_p map. (E) CBF map. (F) CBV map. ROI 1 located in CE lesions (Circle 1), ROI 2 located in the NAWM regions close to the lesions (Circle 2), ROI 3 located in the NAWM regions far from the lesions (Circle 3). For the color maps (C–F), red color represents a high value, blue color represents a low value.
Abbreviations: CBF, cerebral blood flow; CBV, cerebral blood volume; K^trans, volume transfer constant; NAWM, normal-appearing white matter; ROI, region of interest; RRMS, relapsing–remitting multiple sclerosis; V_p, fractional plasma volume.

Table 1 The permeability and perfusion characteristic of MS lesions and NAWM regions

Index	CE	NE	Near NAWM	Far NAWM	χ^2 value	P-value
K^trans	0.2148 (0.0488–0.4525)	0.0326 (0.0195–0.0716)	0.0456 (0.0195–0.0716)	0.0456 (0.0195–0.0781)	26.847	0.000
Vp	0.2448 (0.1758–0.3626)	0.0352 (0.0195–0.0768)	0.0273 (0.0143–0.0468)	0.0299 (0.0143–0.0508)	64.271	0.000
CBF	45.5483 (32.9309–61.3355)	6.8000 (4.3279–11.4639)	6.0588 (4.3205–11.2014)	6.272 (4.4487–10.4447)	69.547	0.000
CBV	39.787 (29.0745–61.6703)	5.8584 (4.0404–10.9631)	5.1239 (4.1287–9.9228)	5.1210 (4.0478–9.4874)	68.930	0.000

Notes: Median (P₂₅–P₇₅) was used to describe the permeability and perfusion characteristic of MS lesions and NAWM regions. Near NAWM: NAWM regions close to lesions. Far NAWM: NAWM regions far from the lesions. K^trans: min⁻¹, V_p: (mL⋅100 g⁻¹), CBF: (mL⋅100 g⁻¹⋅min⁻¹), CBV: (mL⋅100 g⁻¹).

Abbreviations: CBF, cerebral blood flow; CE, contrast-enhancing; CBV, cerebral blood volume; K^trans, volume transfer constant; MS, multiple sclerosis; NAWM, normal-appearing white matter; NE, non-enhancing; V_p, fractional plasma volume.

Table 2 The histogram parameters of MS lesions

	CE	NE	Z value	P-value
K^trans
Skewness	0.6496 (0.0261 – 1.0477)	0.0389 (−0.2269 to 0.4843)	−2.149	0.032
Kurtosis	−0.4065 (−0.8203 to 0.8362)	−0.7569 (−1.1224 to −0.1806)	−1.982	0.048
Vp
Skewness	−0.0338 (−0.2137 to 0.6700)	0.2865 (0.0198 – 0.6297)	−1.122	0.262
Kurtosis	−0.8759 (−1.0820 to 0.1161)	−0.7647 (−1.0969 to −0.1817)	−0.024	0.981
CBF
Skewness	0.1264 (−0.1465 to 0.5258)	0.2588 (−0.1471 to 0.5421)	−0.215	0.830
Kurtosis	−0.9235 (−1.2924 to −0.5948)	−0.7392 (−1.0720 to −0.0897)	−1.408	0.159
CBV
Skewness	0.2741 (−0.0058 to 0.5472)	0.2262 (0.0333 – 0.4631)	−0.382	0.702
Kurtosis	−0.8579 (−1.2466 to −0.4580)	−0.7682 (−1.1318 to −0.1271)	−0.812	0.417

Notes: Median (P₂₅–P₇₅) was used to describe the histogram characteristic of MS lesions. The Mann–Whitney U test in SPSS 21 software was used to compare the differences of these parameters.

Abbreviations: CBF, cerebral blood flow; CE, contrast-enhancing; CBV, cerebral blood volume; K^trans, volume transfer constant; MS, multiple sclerosis; NE, non-enhancing; V_p, fractional plasma volume.

Figure 3 The histogram of K^trans in CE lesions (A) and NE lesions (B).

Note: The skewness of K^trans in CE lesions increased to the right side of histogram, while the histogram of K^trans in NE lesions was more close to normal distribution.
Abbreviations: CE, contrast-enhancing; K^trans, volume transfer constant; NE, non-enhancing.

Figure 4 The skewness and kurtosis of different parameters.

Note: The skewness and kurtosis of K^trans in CE lesions were significantly higher than NE lesions (A), while no significant differences were found in terms of V_p, CBF, and CBV (B–D).
Abbreviations: CBF, cerebral blood flow; CE, contrast-enhancing; CBV, cerebral blood volume; K^trans, volume transfer constant; NE, non-enhancing; V_p, fractional plasma volume.