Table 2

Patients with abnormal neurology and/or abnormal imaging

Patient CMN site and size Neurology Age of onset of abnormal
MRI result Notes
1Whole spine, >10 cm, satellites++Left hemiparesis, progressive scoliosis4 monthsICM Progressive disabling kyphoscoliosis requiring corrective surgery. Left   hemiparesis progressing to spastic paresis of all 4 limbs, but left more affected than right. ?Due to cervical meningeal involvement by melanosis
2Whole spine, >10 cm, few satellitesNormalN/AIncreased signal peritrigonal white matter ?immature myelination
3Right scalp, >10 cm, few satellitesGeneralised seizures, head banging4 monthsRight lateral ventricle choroid plexus papilloma, hydrocephalusBenign choroid plexus papilloma removed age 2 years. Hydrocephalus   presented 4 months postsurgery, and required a ventriculoperitoneal shunt insertion. Generalised seizures and head banging both present before surgery
4Occipital scalp, 5–10 cm, few satellitesHead banging, delayed motor/verbal development17 monthsRight cerebellar astrocytomaDelay of approximately 6 months in gross motor and expressive language at 19   months, but development then normalised
5Spine, >10 cm, scalp, satellites++Left focal seizures + generalisation, global delay18 monthsICM—left temporal lobe, thalamus, left cerebellum, ventral ponsRegression of language skills aged 3–4 years, accompanied by moderate delay in all areas
6Left scalp, >10 cm, satellites++Right focal seizures, right hemiparesis + right homonymous hemianopia6 monthsICM— right thalamus and left pons
7Left knee, 5–10 cm, spine, scalp, satellites+Upper limb spasticity1 monthMidline posterior fossa arachnoid cyst, hydrocephalusCommunicating hydrocephalus presented with sunsetting eyes and enlarging   head, age 1 month. No cause found—not related to posterior fossa arachnoid cyst. Ventriculoperitoneal shunt inserted age 1 month
8Left face, >10 cm, few satellitesLeft squint, delayed speechSquint from birth, speech delay from 18 monthsNormalLeft convergent squint with normal ophthalmological examination. Speech delay of approximately 6 months, age 2 years
9Mid–lower spine, >10 cm, scalp, satellites++Spastic quadriplegia, global delay6 monthsNormalDelay of approximately 6 months in all areas at age 16 months
10Whole spine, >10 cm, satellites++Generalised seizures, later resolved<1 yearNormal