title: Quantitative evaluation of cervical cord compression by computed tomographic myelography in Thoroughbred foals.
abstract: Five Thoroughbred foals (age, 8-33 weeks; median age, 31 weeks; weight, 122-270 kg; median weight, 249 kg) exhibiting ataxia with suspected cervical myelopathy (n=4) and limb malformation (n=1) were subjected to computed tomographic (CT) myelography. The areas of the subarachnoid space and cervical cord were measured on transverse CT images. The area of the cervical cord was divided by the area of subarachnoid space, and stenosis ratios were quantitatively evaluated and compared on the basis of histopathological examination. The sites with a ratio above 52.8% could have been primary lesion sites in the histopathological examination, although one site with a ratio of 54.1% was not a primary lesion site. Therefore, in this study, a ratio between 52.8-54.1% was suggested to be borderline for physical compression that damages the cervical cord. All the cervical vertebrae could not be scanned in three of the five cases. Therefore, CT myelography is not a suitable method for locating the site of compression, but it should be used for quantitative evaluation of cervical stenosis diagnosed by conventional myelography. In conclusion, the stenosis ratios determined using CT myelography could be applicable for detecting primary lesion sites in the cervical cord.
authors.affiliation: Obihiro University of Agriculture and Veterinary Medicine, Hokkaido 080-8555, Japan; Present affiliation: Azabu University, Kanagawa 252-5201, Japan.
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Yamada
authors.affiliation: Hidaka Training and Research Center, Japan Racing Association, Hokkaido 057-0171, Japan.
authors.forename: Fumio
authors.initials: F
authors.lastname: Sato
authors.affiliation: Hidaka Training and Research Center, Japan Racing Association, Hokkaido 057-0171, Japan.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Hada
authors.affiliation: Obihiro University of Agriculture and Veterinary Medicine, Hokkaido 080-8555, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Horiuchi
authors.affiliation: Hidaka Horse Breeders Association, Hokkaido 056-0002, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ikeda
authors.affiliation: Obihiro University of Agriculture and Veterinary Medicine, Hokkaido 080-8555, Japan.
authors.forename: Kahori
authors.initials: K
authors.lastname: Nishihara
authors.affiliation: Obihiro University of Agriculture and Veterinary Medicine, Hokkaido 080-8555, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Sasaki
authors.affiliation: Obihiro University of Agriculture and Veterinary Medicine, Hokkaido 080-8555, Japan.
authors.forename: Yoshiyasu
authors.initials: Y
authors.lastname: Kobayashi
authors.affiliation: Obihiro University of Agriculture and Veterinary Medicine, Hokkaido 080-8555, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Nambo
keywords: Thoroughbred; cervical vertebral compressive myelopathy; computed tomographic myelography; contrast agent; quantitative evaluation