International Veterinary Epilepsy Task Force recommendations for a veterinary epilepsy-specific MRI protocol

Abstract

Epilepsy is one of the most common chronic neurological diseases in veterinary practice. Magnetic resonance imaging (MRI) is regarded as an important diagnostic test to reach the diagnosis of idiopathic epilepsy. However, given that the diagnosis requires the exclusion of other differentials for seizures, the parameters for MRI examination should allow the detection of subtle lesions which may not be obvious with existing techniques. In addition, there are several differentials for idiopathic epilepsy in humans, for example some focal cortical dysplasias, which may only apparent with special sequences, imaging planes and/or particular techniques used in performing the MRI scan. As a result, there is a need to standardize MRI examination in veterinary patients with techniques that reliably diagnose subtle lesions, identify post-seizure changes, and which will allow for future identification of underlying causes of seizures not yet apparent in the veterinary literature.There is a need for a standardized veterinary epilepsy-specific MRI protocol which will facilitate more detailed examination of areas susceptible to generating and perpetuating seizures, is cost efficient, simple to perform and can be adapted for both low and high field scanners. Standardisation of imaging will improve clinical communication and uniformity of case definition between research studies. A 6–7 sequence epilepsy-specific MRI protocol for veterinary patients is proposed and further advanced MR and functional imaging is reviewed.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-015-0466-x) contains supplementary material, which is available to authorized users.

Retrospective epidemiological study of canine epilepsy in Japan using the International Veterinary Epilepsy Task Force classification 2015 (2003–2013): etiological distribution, risk factors, survival time, and lifespan

“…Because this was a retrospective study, blood tests, urinalysis, genetic and/or familial analysis according to the IVETF consensus [6] were not fulfilled in most dogs with IdE. Furthermore, MRI in our study did not correspond to the epilepsy-specific MRI protocol suggested by IVETF [10]. Although we made efforts to follow the IVETF consensus as much as possible, we had to exclude 110 dogs with epilepsy that did not satisfy the criteria e.g., our initial cohort included many dogs that had an initial epileptic seizure onset at <6 months or >6 years and/or showed neurological deficits but were not examined by MRI or CSF analysis due to various reasons such as complications in the dogs and economic compliance of owners.…”

“…Although the MRI performed in this study did not adhere to the epilepsy-specific MRI protocol suggested in the IVETF proposal for the IdE tier II confidence level [6, 10], all MRI scans included T1-weighted, T2-weighted, FLAIR, and contrast-enhanced T1-weighted images in the transverse plane. Images were obtained using a 1.5-Tesla system [Visart® 1.5 Tesla, Toshiba Medical System, Tokyo, Japan (between April 2003 and October 2009)] or 3.0-Tesla system [Signa® HDxt 3.0T, GE Healthcare, Tokyo, Japan (between October 2009 and March 2013)].…”

“…Images were obtained using a 1.5-Tesla system [Visart® 1.5 Tesla, Toshiba Medical System, Tokyo, Japan (between April 2003 and October 2009)] or 3.0-Tesla system [Signa® HDxt 3.0T, GE Healthcare, Tokyo, Japan (between October 2009 and March 2013)]. Furthermore, in cases examined by 3.0-Tesla, 3D T1- (pre- and post-contrast) and T2-weighted images were obtained, with multiplanar reconstructions provided for review, as suggested in the epilepsy-specific MRI protocol [10]. All MR images were reviewed by a neurologist (DH).…”

Postencephalitic epilepsy in dogs with meningoencephalitis of unknown origin: Clinical features, risk factors, and long‐term outcome

“…Bilateral, evenly and diffusely distributed symmetrical and non‐contrast‐enhancing changes were classified as postictal. The presence of concomitant postictal changes in piriform lobes and cingulate gyri, with the same MRI signal characteristics of hippocampus, was used to support the classification of hippocampal changes as postictal . If the hippocampus was involved in the borders of an ipsilateral lesion, it was considered to be lesion‐related.…”

“…The presence of concomitant postictal changes in piriform lobes and cingulate gyri, with the same MRI signal characteristics of hippocampus, was used to support the classification of hippocampal changes as postictal. 26,27 If the hippocampus was involved in the borders of an ipsilateral lesion, it was considered to be lesion-related. Lesions were described as focal, multifocal, or diffuse and unilateral or bilateral.…”