Table 1.

Comparisons between MRI and US

No. of Infants	Inclusion Criteria in weeks	Gestational Age in weeks	Timing of Imaging	HUS Finding Outcome	Study
32	30, CUS and MRI on the same day.	27 (23–30)	Between birth and term	CUS accurately predicted the presence of GMH, IVH, and hemorrhagic parenchymal infarction on MRI. However, its ability to predict the presence of DEHSI and small petechial hemorrhages in the WM on T2 weighted images is not as good, but improves on scans performed at >/=7 days after birth. In addition, normal WM echogenicity on CUS is not a good predictor of normal WM signal intensity on MR	Maalouf et al. (8)
40	>32, US and MRI on the same day.	28.6 (25.1–31.9)	33.2 weeks (27.3–45.1)	WM changes on sequential CUS were predictive of WM changes on MRI. Severely abnormal WM on CUS/MRI was predictive of adverse outcome, and normal-mildly abnormal WM of favorable outcome. Moderately abnormal WM on CUS/MRI was associated with variable outcome.	Leijser et al. (35)
72	>27	25 (23–27)	Term equivalent age.	CUS is highly effective in detecting severe lesions of the white matter in preterm infants, but MRI seems to be necessary for the diagnosis of less severe damage. MRI performed at about the third week of life is highly predictive of the final diagnosis at term.	Horsch et al. (36)
51	>34	29.3 + 2.2	Term equivalent age.	Parenchymal lesions in MRI, excluding subependymal haemorrhages, predicted CP with a sensitivity of 82% and a specificity of 97%, the corresponding figures for CUS being 58% and 100%, respectively.	Valkama et al. (110)
61	Preterm NICU admission.	29.6–32.6 weeks	Early, 32, and late MRI, 40.	Early MRI was superior to cranial US in detecting cysts earlier, especially in preterm infants with c-PVL.	Roelants-van Rijn et al. (114)
167	≥30 or less	27+ 2	Term equivalent age.	Any WM abnormality on MRI and any abnormality on CUS to predict any neurodevelopmental impairement. MRI: sensitivity (84%) and specificity (34%). CUS sensitivity (11%) and specificity (95%).	Woodward et al. (109)

Abbr: GA: gestational age, CUS, cranial ultrasound; MRI, magnetic resonance imaging; GMH, germinal matrix hemorrhage; IVH, intraventricular hemorrhage; WM, white matter; DEHSI, diffuse excessive high signal intensity.