Table 3 MRI characteristics/abnormalities and location of melanocytosis

Group 1: General CMN group

Ruiz-Maldonado et al. [17]

13/13

7/13 (45%) No CNS melanocytosis

Not applicable

Not applicable

Ventricular system asymmetry (n = 4)

Calcifications (n = 2)

Large cisterna magna (n = 2)

Cortical atrophy, loss of cortico subcortical volume (n = 1)

Right frontotemporal subgaleal collection (n = 1)

Foster et al. [9]

42/46

14/42 (33%) (10 CNS melanocytosis)

2/10 (20%)

10/10 (100%)

Middle cranial fossa arachnoid cyst (n = 1)

Chiari type 1 malformation (n = 1)

Tethered spinal cord secondary to a filum terminale fibrolipoma (n = 1)

Transient crescentic enhancement over the right parietal convexity

(that was not evident on repeated examination seven months later) (n = 1)

Bett et al. [48]

Unreported

Unreported

Unreported

Unreported

Dandy-Walker complex (n = 5)

Right hemimegalencephaly (n = 1)

Cerebral cortical dysplasia (n = 1)

Cerebral matrix haemorrhage (n = 1)

Chiari malformation (n = 1)

Choroid plexus tumour (n = 1) Encephalocraniocutaneous lipomatosis (n = 1) Tethered cord (n = 1)

Unknown tumour (n = 1)

Chan et al. [25]

7/39

Head (n = 5)

Spine (n = 2)

0/0 (0%)

Not applicable

Not applicable

Not applicable

Lovett et al. [20]

27/61 (and 1 CT and 1 myelogram)

7/27 (26%) (and 1 CT abnormality)

Unreported

Unreported

CT scan: 2 hyperdense foci (n = 1)

Spinal cord MRI: Mega cisterna magna, increased amount of fluid in post fossa with hydromyelia from C4-T6 (n = 1)

Brain MRI: arachnoid cyst (n = 1)

Ventriculomegaly with haemorrhagic changes, VP shunt, diffuse enhancement of meninges, intraparenchymal hematoma (n = 1)

Bekiesińska-Figatowska et al. [47]

24/24

8/24 (33%)

(CNS melanocytosis)

4/7 (57%)

7/7 (100%)

Neurofibromatosis type 1 (multiple multilevel roots neurofibromas on MRI) (n = 1)

Waelchli et al. [7]

271/271

46/271 (17%)

(36 (13%) CNS melanocytosis)

3/36 (8%)

35/36 (97%)

Dandy-Walker malformation with hydrocephalus (n = 2)

Lack of white matter bulk (n = 2)

Larger ventricles (n = 2)

Benign intradural tumour (n = 1)

Choroid plexus papilloma (n = 1)

Cortical thinning (n = 1)

Extramedullary dural stranding (n = 1)

Filum terminal lipoma (n = 1)

Left frontal lobe meningioma (n = 1)

Leptomeningeal disease (n = 1)

Low volume inferior vermis (n = 1)

Midline posterior fossa arachnoid cyst (n = 1)

Right cerebellar astrocytoma (n = 1)

Small right cerebellar hemisphere (n = 1)

Spinal cord compression (n = 1)

Venous angioma left cerebellar hemisphere (n = 1)

Viana et al. [56]

11/57

Unreported

Unreported

Unreported

Unreported

Wramp et al. [24]

36/83

4/36 (11%) (2 CNS melanocytosis)

Unreported

Unreported

Unreported

Jakchairoongruang et al. [18]

80/80

35/80 (41%) (33 CNS melanocytosis)

5/33 (15%)

33/33 (100%)

Periventricular grey matter heterotopia (n = 3)

Dysmorphic cerebellar hemispheres (n = 2)

Small left-side ventral pons (n = 2)

Small pons and cerebellum (n = 2)

Corpus callosum hypogenesis (n = 1)

Inferior vermian hypoplasia (n = 1)

Small right cerebellar hemisphere (n = 1)

Right temporal lobe polymicrogyria (n = 1)

Vermian hypoplasia (n = 1)

Group 2: Only reporting on neurological signs and symptoms in patients with MRI abnormalities

Bittencourt et al. [23]

38/194

13/38 (34%) (CNS melanocytosis)

Unreported

Unreported

Dandy-Walker syndrome (n = 1)

Ramaswamy et al. [19]

14/14

14/14 (100%)

7/14 (54%) Diffuse leptomeningeal deposits

8/14 (62%)

Lower cervical benign spindle cell tumor (n = 1)

Holocord arachnoid cyst (n = 1)

Cervical/thoracic cyst (n = 1)

Dorsal thoracic cyst (n = 1)

Price et al. [55]

Unreported

12 (CNS melanocytosis)

Unreported

Unreported

Unreported

Qian et al. [21]

13/13

13/13 (100%) (CNS melanocytosis)

13/13 (100%) Diffuse leptomeningeal deposits

Unreported

Leptomeningeal thickening (n = 13)