Prognostic value of magnetic resonance imaging in dogs with paraplegia caused by thoracolumbar intervertebral disk extrusion: 77 cases (2000-2003).
OBJECTIVE
To determine whether magnetic resonance imaging findings in dogs with paraplegia caused by thoracolumbar intervertebral disk extrusion were predictive of clinical outcome.


METHODS
Retrospective case series.


METHODS
77 dogs.


METHODS
Medical records and magnetic resonance images were reviewed; clinical outcome was classified as successful (regained ability to walk with no more than mild neurologic deficits) or unsuccessful (severe neurologic deficits persisted). The prognostic value of magnetic resonance imaging was compared with prognostic value of deep pain perception, duration of clinical signs, and rate of onset of clinical signs.


RESULTS
33 (43%) dogs had areas of hyperintensity of the spinal cord greater than or equal to the length of the L2 vertebral body on T2-weighted magnetic resonance images. All 44 dogs without areas of hyperintensity on T2-weighted images had a successful outcome, but only 18 of the 33 (55%) dogs with an area of hyperintensity did. Only 5 of 16 dogs with an area of hyperintensity that had also lost deep pain perception had a successful outcome. The odds ratio for an unsuccessful outcome for a dog with an area of hyperintensity (29.87) was higher than the odds ratio for a dog that had lost deep pain perception (5.24). Duration and rate of onset of clinical signs were not associated with clinical outcome.


CONCLUSIONS
Findings suggest that results of magnetic resonance imaging can be used to predict clinical outcome in dogs with paraplegia caused by intervertebral disk extrusion.
Ito
Daisuke
D
Laboratories of Veterinary Emergency Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Matsunaga
Satoru
S
Jeffery
Nick D
ND
Sasaki
Nobuo
N
Nishimura
Ryohei
R
Mochizuki
Manabu
M
Kasahara
Mihoko
M
Fujiwara
Reina
R
Ogawa
Hiroyuki
H
D000818:Animals; D001416:Back Pain / Q000175:diagnosis / Q000209:etiology / Q000473:pathology / Q000662:veterinary; D004283:Dog Diseases / Q000175:diagnosis* / Q000473:pathology; D004285:Dogs; D005260:Female; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000662:veterinary*; D008297:Male; D016017:Odds Ratio; D010264:Paraplegia / Q000175:diagnosis / Q000209:etiology / Q000473:pathology / Q000662:veterinary*; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D013117:Spinal Cord Compression / Q000175:diagnosis / Q000209:etiology / Q000473:pathology / Q000662:veterinary; D016896:Treatment Outcome