Intracranial calcification (ICC) can be either physiological or pathological. Physiological ICC is not an expected neuroimaging finding in the neonatal period but can be seen as children grow older in the pineal gland, habenula, choroid plexus, and occasionally in the dura mater. Pathological ICC can be broadly divided into six groups: infectious, toxic, neurodegenerative, neoplastic, vascular, and syndromic. The first two groups are typically composed of diseases that more commonly result in static encephalopathies, whereas the last four groups are composed of diseases that tend to cause progressive encephalopathy. Various neuroimaging modalities have distinct utilities and sensitivities in the depiction of ICC. Age at presentation, ICC location, and additional neuroimaging findings are useful information that may be useful to narrow down the differential diagnosis of ICC. Bilateral ICC is commonly due to congenital infections or due to neurodegenerative or infectious diseases. ICC involving the basal ganglia and thalami are commonly seen in neurodegenerative diseases. ICC can be seen in isolation or be associated with other neuroimaging features. TORCH infections are the most common neonatal causes of ICC. ICC in congenital infections can be associated with clastic changes, hydrocephalus, chorioretinitis, white matter abnormalities, skull changes, and cortical development malformations. Specific non-infectious causes of ICC that mimic TORCH infections are known as pseudo-TORCH. Neurodegenerative diseases causing ICC are mainly due to parathyroid and thyroid hormone dysfunction and inborn errors of metabolism, such as MELAS, Kearns Sayre and Cockayne syndrome, interferonopathies syndrome, and Krabbe disease. Tumoral ICCs are more commonly seen in low-grade tumors. Arteriovenous malformations, arteriovenous fistulas, chronic venous hypertension, and cavernomas are also known causes of ICC. Other vascular causes of ICC include atherosclerosis, healed hematoma, radiotherapy treatment, old infarct, and disorders of the microvasculature such as COL4A1- and COL4A2-related diseases. Down syndrome and phakomatosis are also known causes of ICC. Clinical information such as age at presentation; maternal exposure to teratogens, such as virus; in addition to the association with chromosomal abnormalities; genetic mutations and postnatal infections, facilitate in the differential diagnosis of the multiple causes of ICC.
SPR 2020 Annual Meeting & Postgraduate Course
Alves Cesar Augusto,