Computed tomographic and histological findings of Hansen type I intervertebral disc herniation in dogs

K. Kuroki; C. L. Vitale; S. C. Essman; P. Pithua; J. R. Coates

doi:10.3415/VCOT-12-08-0105

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 2013; 26(05): 379-384
DOI: 10.3415/VCOT-12-08-0105

Original Research

Schattauer GmbH

Computed tomographic and histological findings of Hansen type I intervertebral disc herniation in dogs

K. Kuroki

¹Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA

,

C. L. Vitale

²Veterinary Medical Teaching Hospital, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA.

,

S. C. Essman

²Veterinary Medical Teaching Hospital, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA.

,

P. Pithua

²Veterinary Medical Teaching Hospital, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA.

,

J. R. Coates

²Veterinary Medical Teaching Hospital, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA.

› Author Affiliations

Abstract

Summary

Objective: To evaluate whether noncontrast-enhanced computed tomography (CT) as a stand-alone imaging modality can be used to define the Hansen type I intervertebral disc herniation (IVDH) lesion and also whether the Hounsfield unit (HU) value of herniated disc is relevant to clinical duration and to histopathological chronicity of extruded disc material.

Methods: Information from a series of CT studies performed on 45 dogs with a presumptive diagnosis of Hansen type I IVDH was used. Clinical duration of IVDH was estimated based on time from onset of signs per owner communication to time of surgical intervention. Hansen type I IVDH was confirmed at surgery. Retrieved herniated disc was histologically examined. The HU values were analyzed to correlate the clinical duration and histopathological chronicity of the disc lesion.

Results: Non-contrast-enhanced CT provided sufficient diagnostic information to plan surgery in 42 of 45 dogs (93%). The value of the HU was significantly higher in clinically chronic cases (n = 12) compared to peracute cases (n = 11) (p <0.05). The HU values were significantly correlated with clinical duration (r = 0.482, p = 0.0008) and histopathological chronicity of the herniated disc (r = 0.408, p = 0.0056).

Conclusion: Consistent with the previous reports, the use of non-contrast-enhanced CT alone was sufficient for the diagnosis and surgical planning in most patients with Hansen type I IVDH in the thoracolumbar spine. In addition, the present study suggested that HU values on CT images may be useful in the evaluation of disease chronicity of IVDH.

Keywords

Histopathology - computed tomography - Hounsfield units - dog - intervertebral disc herniation

Full Text

References

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