Table 1 Applied definitions and magnetic resonance imaging parameters in studies of silent cerebral infarcts in sickle cell disease patients

Abboud et al. 2011 [19]

–

5.0

T1: ax | FLAIR: ax, cor

Evidence of cerebral infarction on MRI

No history of overt stroke

Arkuszewski et al. 2014 [20]

3.0 T

–

FLAIR

Area of abnormal hyperintensity, ≥ 3 mm on FLAIR, visible on at least two perpendicular planes

–

Asbeutah et al. 2014 [21]

1.5 T

5.0

T1: ax, sag | T2: ax, sag | FLAIR

–

–

Baldeweg et al. 2006 [22]

1.5 T

–

T1: sag, cor | T2: ax | FLAIR: cor

Area of abnormal hyperintensity on T2

No history of a focal neurological deficit lasting > 24 h

Bernaudin et al. 2011 [23]

1.0 or 1.5 T

–

T1 | T2 | FLAIR

Signal abnormality, ≥ 3 mm in one dimension, visible on two views on T2

No history of overt stroke and normal neurologic examination

De Blank et al. 2010 [24]

–

–

–

Evidence of cerebral infarction on MRI

No overt neurological symptoms

Brousse et al. 2017 [25]

–

–

–

–

–

Brown et al. 2000 [26]

–

–

–

Evidence of cerebral infarction on MRI

No history of overt stroke and normal neurological examination

Calvet et al. 2017 [27]

3.0 T

–

T2 | FLAIR

White matter lesions, i.e. poorly defined hyperintensities, ≥ 5 mm on T2 or FLAIR

No history of overt stroke or overt neurological symptoms

Coloigner et al. 2017 [28]

3.0 T

1.0 or 1.3 or 5.0

3D T1 | 3D T2 |

≥ 3 mm lesions on 3D T2 observed in two orthogonal planes

No history of overt stroke

Dowling et al. 2012 [29]

1.5 or 3.0 T

–

FLAIR: ax

Area of abnormal hyperintensity intensity in multiple T2

No history or physical findings of a focal neurological deficit lasting > 24 h

Ford et al. 2017 [30]

–

–

T1 |FLAIR

Area of abnormal hyperintensity on FLAIR > 3 mm and cerebrospinal fluid-like hypointensity on T1

–

Ford et al. 2018 [31]

–

–

T1 |FLAIR

Signal abnormality, ≥ 3 mm in one dimension, visible on two planes on FLAIR T2

Normal neurological examination or absence of neurological symptoms that correlate with lesion location

Gold et al. 2008 [32]

–

–

–

–

–

Guilliams et al. 2015 [33]

1.5 or 3.0 T

5.0

T1: sag | T2: ax |FLAIR: ax, cor

Signal abnormality, ≥ 3 mm in one dimension, visible on two planes on T2 or FLAIR

Absence of neurological symptoms that correlate with lesion location

Gyang et al. 2011 [34]

–

–

–

Abnormal MRI changes

No neurological symptoms

Issar et al. 2018 [35]

1.5 T

–

T1: ax | T1 FLAIR: sag | T2: ax |FLAIR: ax

Areas of abnormal hyperintensity on FLAIR T2

Absence of overt clinical neurological symptoms

Kassim et al. 2016 [36]

–

–

T2

≥ 3 mm on T2 in two imaging planes

No history of neurological deficits and normal neurological examination

Kawadler et al. 2018 [37]

1.5 T

–

T2: ax

–

–

Kwiatkowski et al. 2009 [6]

1.5 T

–

FLAIR

Area of abnormal hyperintensity on T2 and FLAIR

No history of overt stroke or motor deficits that can be attributed to the lesion

Melek et al. 2006 [38]

1.5 T

5.0

T1: sag, ax | T2: sag, ax | PD: ax

Abnormal MRI

No history or physical findings of a focal neurological deficit lasting > 24 h

Mercuri et al. 1995 [39]

1.0 T

6.0

T2

–

–

Oguz et al. 2003 [40]

1.5 T

5.0

T1: sag | T2: ax | FLAIR

–

–

Onofri et al. 2012 [41]

1.5 T

5.0

FLAIR: ax

–

–

Pegelow et al. 2001 [42]

–

5.0

T1: ax | PD T2: ax, cor

–

–

Pegelow et al. 2002 [10]

–

–

–

Abnormal MRI

No neurological deficit

Quinn et al. 2013 [43]

–

–

FLAIR

Signal abnormality ≥ 3 mm in one dimension, visible on at least two views of T2 FLAIR

Normal neurological examination or absence of neurological symptoms that correlate with lesion location

Schatz et al. 2006 [44]

1.5 T

5.0

T1: sag | T2: ax

Area of abnormal hyperintensity, ≥ 3 mm on T2

Normal neurological history

Seibert et al. 1993 [45]

1.5 T

–

T1 | T2 | PD: ax

–

–

Silva et al. 2009 [46]

1.5 T

5.0

T1: sag, ax | T2 | FLAIR: ax

Evidence of ischaemia, including lacunar infarction, encephalomalacia, atrophy or leukoencephalopathy

–

Solomou et al. 2013 [47]

1.0 T

5.0

T2: ax, cor | FLAIR: ax, cor

Focal (< 1 cm) or multiple (> 1 cm) high-intensity lesions on T2 or FLAIR

Absence of physical findings of overt stroke

Steen et al. 2003 [48]

1.5 T

5.0 or 3.0

T1: ax | T2: ax |FLAIR: ax

Evidence of ischaemia, including lacunar infarction, encephalomalacia, atrophy or leukoencephalopathy

Absence of a clinical history of stroke

Tewari et al. 2018 [49]

–

–

FLAIR

Area of abnormal hyperintensity ≥ 3 mm in diameter and visible in at least two planes of T2 (ax and cor)

No history or physical findings of a focal neurological deficit in a corresponding localizing vascular distribution

Václavů et al. 2019 [50]

3.0 T

–

3D FLAIR

Multiple (> 1) hyperintensities ≥ 5 mm

–

Van der Land et al. 2015 [51]

3.0 and 7.0 T

–

T1 |FLAIR: ax

Areas of abnormal hyperintensity

No history or physical findings of a focal neurological deficit

Van der Land et al. 2016 [52]

3.0 T

5.0

T2 |FLAIR

Hyperintensity of variable size in the white matter on FLAIR, without cavitation

No history or physical findings of a focal neurological deficit

Vichinsky et al. 2010 [53]

1.5 T

–

T1 | T2 | PD

Area of abnormal hyperintensity at least 5 mm on T2 and PD, with corresponding hypointensity on T1

–

Wang et al. 1998 [54]

1.5 T

5.0

T1: ax | T2: ax

Area of abnormal hyperintensity on T2

No history of neurological symptoms compatible with overt stroke

Wang et al. 2008 [55]

1.5 T

5.0

T1: ax |FLAIR: ax, cor

Area of abnormal hyperintensity on T2, consistent with an ischaemic lesion in white matter

–

Watkins et al. 1998 [56]

1.5 T

5.0

T2: ax

–

–

Zafeiriou et al. 2004 [57]

1.5 T

T1: ax

Area of abnormal hyperintensity on T2

–