The Spatial Relationship between Apparent Diffusion Coefficient and Standardized Uptake Value of ¹⁸F-Fluorodeoxyglucose Has a Crucial Influence on the Numeric Correlation of Both Parameters in PET/MRI of Lung Tumors

Table 1

Average standardized uptake values and intratumoral ADC values of the groups analyzed with sequential PET/MRI (mean ± SD). Values are given separately for both readers: maximum standardized uptake value (), mean standardized uptake value (), minimum apparent diffusion coefficient (ADC), and mean apparent diffusion coefficient ().

Reader 1	All tumors; ()	Spatial mismatch; (all diameters > 3 cm, )	Spatial match; (all, )	Spatial match; (diameter < 3 cm, )	Spatial match; (diameter > 3 cm, )
	11.2 ± 5.9	13.4 ± 6.3	10.2 ± 5.6	8.0 ± 4.8	13.5 ± 5.3
	6.8 ± 3.3	7.7 ± 3.3	6.1 ± 3.3	4.8 ± 2.8	8.0 ± 3.2
(10^−6 mm^2/s)	555 ± 244	492 ± 172	585 ± 271	647 ± 245	497 ± 300
(10^−6 mm^2/s)	1340 ± 252	1239 ± 162	1387 ± 276	1398 ± 279	1372 ± 293
Mean distance; and (mm)	12.7 ± 8.7	22.4 ± 9.0	8.2 ± 3.1	7.5 ± 3.0	9.0 ± 3.4
Mean tumor diameter (mm)	51.4 ± 31.5	77.1 ± 34.6	39.3 ± 22.0	25.8 ± 2.2	58.7 ± 23.2
Reader 3	All tumors ()	Spatial mismatch; ()	Spatial match; (all, )	Spatial match; (diameter < 3 cm, )	Spatial match; (diameter > 3 cm, )
	11.2 ± 5.9	13.1 ± 5.6	10.0 ± 6.0	6.9 ± 3.5	14.8 ± 5.9
	6.6 ± 3.3	7.6 ± 3.0	6.2 ± 3.4	4.2 ± 2.1	8.7 ± 3.5
(10^−6 mm^2/s)	494 ± 268	325 ± 140	607 ± 277	679 ± 240	498 ± 315
(10^−6 mm^2/s)	1378 ± 345	1225 ± 129	1480 ± 406	1433 ± 312	1550 ± 544
Mean distance; and (mm)	15.2 ± 10.5	25.5 ± 9.2	8.3 ± 3.0	7.6 ± 3.0	9.3 ± 2.9
Mean tumor diameter (mm)	51.4 ± 31.5	66.0 ± 35.0	41.7 ± 25.8	25.8 ± 2.3	65.6 ± 26.8