Neuro-osteology.

Neuro-osteology stresses the biological connection during development between nerve and hard tissues. It is a perspective that has developed since associations were first described between pre-natal peripheral nerve tissue and initial osseous bone formation in the craniofacial skeleton (Kjaer, 1990a). In this review, the normal connection between the central nervous system and the axial skeleton and between the peripheral nervous system and jaw formation are first discussed. The early central nervous system (the neural tube) and the axial skeleton from the lumbosacral region to the sella turcica forms a unit, since both types of tissue are developmentally dependent upon the notochord. In different neurological disorders, the axial skeleton, including the pituitary gland, is malformed in different ways along the original course of the notochord. Anterior to the pituitary gland/sella turcica region, the craniofacial skeleton develops from prechordal cartilage, invading mesoderm and neural crest cells. Also, abnormal development in the craniofacial region, such as tooth agenesis, is analyzed neuro-osteologically. Results from pre-natal investigations provide information on the post-natal diagnosis of children with congenital developmental disorders in the central nervous system. Examples of these are myelomeningocele and holoprosencephaly. Three steps are important in clinical neuro-osteology: (1) clinical definition of the region of an osseous or dental malformation, (2) embryological determination of the origin of that region and recollection of which neurological structure has developed from the same region, and (3) clinical diagnosis of this neurological structure. If neurological malformation is the first symptom, step 2 results in the determination of the osseous region involved, which in step 3 is analyzed clinically. The relevance of future neuro-osteological diagnostics is emphasized.

Clinical, radiographic, and pathological features of symptomatic Rathke's cleft cysts.

The clinical, radiographic, and pathological findings in 155 patients with symptomatic Rathke's cleft cysts are discussed. Eight patients were treated by the authors and 147 were collected in a review of the literature. This lesion occurred more often in female than male patients by a 2:1 margin, and the mean age at presentation was 38 years. The average patient had been symptomatic for nearly 3 years at the time of treatment, with the most common symptoms and signs being pituitary dysfunction, visual disturbances, and headaches. Affected children generally were pituitary dwarfs. The sella was enlarged in 80% of cases, and the cyst was situated in both an intrasellar and a suprasellar location in 71%. Computerized tomography revealed a low-density cystic mass with capsular enhancement in one-half of the cases. A variable appearance was seen with magnetic resonance imaging. Partial excision and drainage of the cyst by the transsphenoidal approach is the recommended treatment, as the recurrence rate is low. Most symptoms and signs improved or resolved following surgery with the exception of hypopituitarism and diabetes insipidus. The cyst lining was usually composed of ciliated cuboidal or columnar epithelium. Theories as to the origin of Rathke's cleft cysts are also discussed.