COMMUNICATING HYDROCEPHALUS IN DOGS WITH CONGENITAL CILIARY DYSFUNCTION

Magnetic resonance imaging (MRI) and radionuclide ventriculography wer e performed in 5 dogs with congenital ciliary dysfunction (CCD) and 3 normal dogs. Ventricular and brain dimensions and volumes, and CSF flo w rates were measured or calculated from the MR images and radionuclid e clearance. All CCD dogs had hydrocephalus based on previously publis hed criteria of a percent vertical brain dimension (PVBD) greater than 14%. The PVBD was significantly larger (p=0.001) in the dogs with CCD (mean+/-SD) 33.00+/-5.42% than in normal dogs 11.07+/-0.61%. The vent ricular volume was significantly larger (p=0.021) in CCD dogs 10,841+/ -4,127 mm(3) compared to the volume measured in normal dogs 3,069+/-1, 167 mm(3). The CSF flow rate was not significantly different (p=0.876) between CCD dogs (253.00+/-147.25 mm(3)/h) and normal dogs (267.667+/ -47.61 mm(3)/h). This suggests that the ventricular dilation in CCD do gs is not due to impedance of CSF flow from the ventricular system by dysfunctional ependymal cilia.