Diagnosing the cause of intracranial calcification may be difficult and require a high degree of paediatric neurological or paediatric neuroradiological expertise. Workers in Leeds, Manchester and Amsterdam (Developmental Medicine and Child Neurology 2013;55:46–57 see also Commentary, ibid: 7–8) have used a neuroimaging pattern recognition approach and proposed a new classification system. They analysed 244 scans (140 CT, 104 MRI) from 119 patients (mostly children but a few adults). The clinical details and scans of patients were sent to the authors because of their known interests, particularly in Aicardi-Goutières syndrome (AGS) and the series was therefore highly selective. A diagnosis was available for 59 patients, including 33 with AGS. No patient with prenatal viral infection such as cytomegalovirus infection was referred. The most frequent other diagnoses were cerebroretinal microangiopathy with calcification and cysts (10 patients), band-like calcification with simplified gyration and polymicrogyria (BLC-PMG) (6), and COL4A1 mutation related disease (3); others included Degos disease, Krabbe disease, Alexander disease, mitochondrial disease, and tetrasomy 15. Characteristic patterns of calcification were identified for AGS, BLC-PMG and COL4A1 mutation related disease, and for some other groups of cases characteristic neuroimaging phenotypes were delineated, raising the possibility of discovering new genotypes and pathological mechanisms. It is hoped that …