Endocranial vascular patterns in a familial rabbit model of coronal suturesynostosis

Objective: The present study investigates the potential relationship betwee n craniosynostosis and any changes in endocranial vasculature. The hypothes is that crania from rabbits with familial, nonsyndromic coronal suture syno stosis and crania from rabbits with experimental immobilization of the coro nal suture are associated with altered form of the middle meningeal vessels and dural venous sinuses is tested. Design: Silicone rubber endocasts from 14 adult New Zealand white rabbits ( Oryctolagus cuniculus) with familial nonsyndromic coronal suture synostosis (five with bilateral coronal suture synostosis and nine with unilateral co ronal suture synostosis) were made to assess middle meningeal vessel and du ral venous sinus form. For comparative purposes, endocasts were made from 2 5 rabbits with normal, patent coronal sutures and 10 rabbits with experimen tal immobilization of the coronal suture. Impressions of the dural venous s inuses were assessed for depth and width. The area of the confluens of sinu ses was also assessed. Impressions of the middle meningeal vessels were ass essed for depth, width, and degree of convolution. For width of the dural v enous sinuses and area of the confluens of sinuses, comparisons among group s were made with a one-way analysis of variance (ANOVA). For depth of the d ural venous sinuses and impressions of the middle meningeal vessels, compar isons among groups were made using a Kruskal-Wallis one-way ANOVA. Results: Crania with familial coronal suture synostosis had significantly ( p < .05) reduced posterior dural venous sinus dimensions when compared with both crania from rabbits with experimental immobilization of the coronal s uture and rabbits with normal Corona[ sutures. Crania with both coronal sut ure synostosis and experimental immobilization had significant increases in dimensions of the middle meningeal vessels relative to normal crania. In a ddition, casts from rabbits with unicoronal suture synostosis showed marked asymmetry in the dural venous sinuses. Conclusions: These results support the hypothesis that craniosynostosis is associated with alterations in endocranial vasculature. These changes are m ost likely a secondary response to synostosis rather than a causal factor a nd may reflect increased intracranial pressure, decreased intracranial volu me, and local accumulations and reductions of cerebrospinal fluid in the po sterior region of the skull and immediately deep to the coronal suture.