Reduction in head size in patients with aspartylglucosaminuria.

To show that the head may shrink in adult patients with aspartylglucosaminuria (AGU), a neurodegenerative disease. The head circumference (HC) of 40 adult patients (age at baseline 15 to 47) was measured twice with an interval of 10 years. Of these 40, 21 aged 15-47 and 19 young patients aged 5-14 as well as 40 healthy controls underwent lateral cephalometric radiography. During 10 years' follow-up, the HC of 26 (65%) had decreased by 1 to 4.5 cm (mean 1.7, P < 0.001). Evaluation of lateral skull radiographs revealed that patients aged 15 or more had significantly thicker skulls than did younger patients (P = 0.015). Mean intracranial length (glabella-opisthocranium) of the patients aged 15 or more was significantly shorter than in patients aged 14 years or less (P = 0.029). These measurements indicated that brain volume had decreased. Macrocephalia in childhood followed by reduced brain volume in adulthood is evident in patients with AGU and is reflected by a decrease in head size.