Osteopetrosis with Arnold Chiari malformation type I

Abstract

Osteopetrosis is a rare genetic disorder resulting in increased bone density and decreased bone remodelling. Bone expansion results in the crowding of neural foramina causing cranial nerve compression. Here, we describe a female infant in her mid infancy presented with no eye contact since birth, and abdominal distension for 2 months. On CT evaluation, sclerotic bones with bilateral optic canal narrowing were present. A crowded posterior fossa with Arnold Chiari type I malformation was seen on MRI evaluation, suggesting a rare association of osteopetrosis with Arnold Chiari's malformation.

Keywords: congenital disorders; neuroimaging; paediatric prescribing; radiology.

Figure 1

Non-contrast CT (NCCT), MRI and X-ray image showing osteopetrosis with Arnold Chiari malformation. Axial NCCT scan (A, B, D) and coronal CT scan (C) showed the reduced calibre of the optic nerve with optic canal and increased bone density in the bilateral petrous bone. MRI (E) showing hydrocephalus. MRI (F, I) showed tonsillar herniation. MRI (H, G) showed thinned bilateral optic nerves with the optic canal. MRI (J) showed developed cochlea and semicircular canals. Skeletal X-ray image (K, L) showed increased bone density with a lack of corticomedullary differentiation. Fraying and splaying of the metaphyseal ends of visualised long bones with beading at anterior costochondral junctions.