Relevant disease terminology
The first known case of this disease was described by a French doctor by the name of A. Delacour in 1850, i.e. 80 years before the German doctor Karl Theodor Fahr (1877 - 1945) published his case report in 1930 (1, 5). However, based on current knowledge, Fahr's case report now appears to be a secondary manifestation of hypoparathyroidism (6) rather than a primary form of brain calcification.
Eponyms can have a cultural value, but from a clinical perspective, it is more useful for disease names to convey pathophysiological disease mechanisms. In this case, it is also useful that the disease name differentiates the disease from secondary brain calcifications due to infection, metabolic disorders, or normal ageing (7).
Fahr's disease has often been referred to as idiopathic basal ganglia calcification, i.e. calcifications located in the basal ganglia without a known cause. This term is a good description of the anatomical location of the calcifications, but the word 'idiopathic' is no longer adequate as the condition has now been shown to have a genetic cause. Furthermore, the calcifications can also occur in other areas of the brain, such as the subcortical white matter, thalamus and cerebellum (8).
In recent years, the term primary familial brain calcification (in Norwegian, primær familiær hjerneforkalkning) seems to be the most commonly used in international medical literature. One advantage of this term is that it clearly refers to brain calcifications of genetic origin. A disadvantage is that it excludes cases arising from spontaneous mutations. Such cases can be referred to as primary bilateral brain calcification (5).