1
|
Löscher W. Dogs as a Natural Animal Model of Epilepsy. Front Vet Sci 2022; 9:928009. [PMID: 35812852 PMCID: PMC9257283 DOI: 10.3389/fvets.2022.928009] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 05/18/2022] [Indexed: 12/13/2022] Open
Abstract
Epilepsy is a common neurological disease in both humans and domestic dogs, making dogs an ideal translational model of epilepsy. In both species, epilepsy is a complex brain disease characterized by an enduring predisposition to generate spontaneous recurrent epileptic seizures. Furthermore, as in humans, status epilepticus is one of the more common neurological emergencies in dogs with epilepsy. In both species, epilepsy is not a single disease but a group of disorders characterized by a broad array of clinical signs, age of onset, and underlying causes. Brain imaging suggests that the limbic system, including the hippocampus and cingulate gyrus, is often affected in canine epilepsy, which could explain the high incidence of comorbid behavioral problems such as anxiety and cognitive alterations. Resistance to antiseizure medications is a significant problem in both canine and human epilepsy, so dogs can be used to study mechanisms of drug resistance and develop novel therapeutic strategies to benefit both species. Importantly, dogs are large enough to accommodate intracranial EEG and responsive neurostimulation devices designed for humans. Studies in epileptic dogs with such devices have reported ictal and interictal events that are remarkably similar to those occurring in human epilepsy. Continuous (24/7) EEG recordings in a select group of epileptic dogs for >1 year have provided a rich dataset of unprecedented length for studying seizure periodicities and developing new methods for seizure forecasting. The data presented in this review substantiate that canine epilepsy is an excellent translational model for several facets of epilepsy research. Furthermore, several techniques of inducing seizures in laboratory dogs are discussed as related to therapeutic advances. Importantly, the development of vagus nerve stimulation as a novel therapy for drug-resistant epilepsy in people was based on a series of studies in dogs with induced seizures. Dogs with naturally occurring or induced seizures provide excellent large-animal models to bridge the translational gap between rodents and humans in the development of novel therapies. Furthermore, because the dog is not only a preclinical species for human medicine but also a potential patient and pet, research on this species serves both veterinary and human medicine.
Collapse
Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
- *Correspondence: Wolfgang Löscher
| |
Collapse
|
2
|
Asada R, Hamamoto Y, Yu Y, Mizuno S, Chambers JK, Uchida K, Hasegawa D. Ventrolateral temporal lobectomy in normal dogs as a counterpart to human anterior temporal lobectomy: a preliminary study on the surgical procedure and complications. J Vet Med Sci 2021; 83:1513-1520. [PMID: 34408102 PMCID: PMC8569885 DOI: 10.1292/jvms.21-0127] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Anterior temporal lobectomy (ATL) is a surgical procedure for drug-resistant mesial temporal lobe epilepsy that is commonly performed in human medicine. The purpose of this study was to determine whether ATL-like surgery, i.e., removal of the amygdala and hippocampal head, is possible in dogs, and to investigate its safety and postoperative complications. Eight healthy beagles underwent ATL-like surgery and were observed for 3 months postoperatively. Samples from the surgically resected tissues and postmortem brain were evaluated pathologically. The surgical survival rate was 62.5%. The major postoperative complications were visual impairment, temporal muscle atrophy on the operative side, and a postoperative acute symptomatic seizure. Due to the anatomical differences between dogs and humans, the surgically resected area to approach the medial temporal structures in dogs was the ventrolateral part of the temporal lobe. Therefore, the ATL-like surgery described in this study was named "ventrolateral temporal lobectomy" (VTL). This study is the first report of temporal lobectomy including amygdalohippocampectomy in veterinary medicine and demonstrates its feasibility. Although it requires some degree of skill, VTL could be a treatment option for canine drug-resistant epilepsy and lesions in the mesial temporal lobe.
Collapse
Affiliation(s)
- Rikako Asada
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan
| | - Yuji Hamamoto
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan.,Research Center for Animal Life Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan
| | - Yoshihiko Yu
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan.,Research Center for Animal Life Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan
| | - Satoshi Mizuno
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan
| | - James K Chambers
- Laboratory of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Kazuyuki Uchida
- Laboratory of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Daisuke Hasegawa
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan.,Research Center for Animal Life Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan
| |
Collapse
|
3
|
Hirashima J, Saito M, Igarashi H, Takagi S, Hasegawa D. Case Report: 1-Year Follow-Up of Vagus Nerve Stimulation in a Dog With Drug-Resistant Epilepsy. Front Vet Sci 2021; 8:708407. [PMID: 34355037 PMCID: PMC8330973 DOI: 10.3389/fvets.2021.708407] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/11/2021] [Indexed: 12/02/2022] Open
Abstract
A vagus nerve stimulation (VNS) system was surgically implanted to treat drug-resistant epilepsy in a 5-year-old male Shetland Sheepdog. At regular visits during a 1-year follow-up, treatment efficacy and adverse effects were assessed, and programmable stimulation parameters were adjusted to optimize stimulation intensity while avoiding adverse effects. The frequency of generalized tonic–clonic seizures was reduced by 87% after the initiation of VNS. The owner reported that the dog regained his personality, and the quality of life of both the dog and owner improved. The only adverse effect of VNS was a cough that was controlled by adjusting stimulation parameters. There were no surgical complications or other issues with the VNS device. This is the first long-term evaluation of VNS therapy in a dog, and the results obtained suggest that gradual adjustments of VNS parameters facilitate optimum VNS dosing.
Collapse
Affiliation(s)
- Junya Hirashima
- Laboratory of Small Animal Surgery (Neurology), School of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Miyoko Saito
- Laboratory of Small Animal Surgery (Neurology), School of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Hirotaka Igarashi
- Laboratory of Small Animal Internal Medicine, School of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Satoshi Takagi
- Laboratory of Small Animal Surgery (Soft Tissue Surgery and Surgical Oncology), School of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Daisuke Hasegawa
- Laboratory of Veterinary Radiology, Nippon Veterinary and Life Science University, Musashino, Japan.,The Research Center for Animal Life Science, Nippon Veterinary and Life Science University, Musashino, Japan
| |
Collapse
|
4
|
Hasegawa D, Asada R, Hamamoto Y, Yu Y, Kuwabara T, Mizoguchi S, Chambers JK, Uchida K. Focal Cortical Resection and Hippocampectomy in a Cat With Drug-Resistant Structural Epilepsy. Front Vet Sci 2021; 8:719455. [PMID: 34355038 PMCID: PMC8329420 DOI: 10.3389/fvets.2021.719455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 06/25/2021] [Indexed: 11/13/2022] Open
Abstract
Epilepsy surgery is a common therapeutic option in humans with drug-resistant epilepsy. However, there are few reports of intracranial epilepsy surgery for naturally occurring epilepsy in veterinary medicine. A 12-year-old neutered male domestic shorthair cat with presumed congenital cortical abnormalities (atrophy) in the right temporo-occipital cortex and hippocampus had been affected with epilepsy from 3 months of age. In addition to recurrent epileptic seizures, the cat exhibited cognitive dysfunction, bilateral blindness, and right forebrain signs. Seizures had been partially controlled (approximately 0.3–0.7 seizures per month) by phenobarbital, zonisamide, diazepam, and gabapentin until 10 years of age; however, they gradually became uncontrollable (approximately 2–3 seizures per month). In order to plan epilepsy surgery, presurgical evaluations including advanced structural magnetic resonance imaging and long-term intracranial video-electroencephalography monitoring were conducted to identify the epileptogenic zone. The epileptogenic zone was suspected in the right atrophied temporo-occipital cortex and hippocampus. Two-step surgery was planned, and a focal cortical resection of that area was performed initially. After the first surgery, seizures were not observed for 2 months, but they then recurred. The second surgery was performed to remove the right atrophic hippocampus and extended area of the right cortex, which showed spikes on intraoperative electrocorticography. After the second operation, although epileptogenic spikes remained in the contralateral occipital lobe, which was suspected as the second epileptogenic focus, seizure frequency decreased to <0.3 seizure per month under treatment with antiseizure drugs at 1.5 years after surgery. There were no apparent complications associated with either operation, although the original neurological signs were unchanged. This is the first exploratory study of intracranial epilepsy surgery for naturally occurring epilepsy, with modern electroclinical and imaging evidence, in veterinary medicine. Along with the spread of advanced diagnostic modalities and neurosurgical devices in veterinary medicine, epilepsy surgery may be an alternative treatment option for drug-resistant epilepsy in cats.
Collapse
Affiliation(s)
- Daisuke Hasegawa
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Musashino, Japan.,The Research Center of Animal Life Science, Nippon Veterinary and Life Science University, Musashino, Japan
| | - Rikako Asada
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Musashino, Japan
| | - Yuji Hamamoto
- Veterinary Medical Teaching Hospital, Nippon Veterinary and Life Science University, Musashino, Japan
| | - Yoshihiko Yu
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Musashino, Japan
| | - Takayuki Kuwabara
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Musashino, Japan
| | - Shunta Mizoguchi
- Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Musashino, Japan
| | - James K Chambers
- Laboratory of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Japan
| | - Kazuyuki Uchida
- Laboratory of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Japan
| |
Collapse
|
5
|
Jones GMC, Volk HA, Packer RMA. Research priorities for idiopathic epilepsy in dogs: Viewpoints of owners, general practice veterinarians, and neurology specialists. J Vet Intern Med 2021; 35:1466-1479. [PMID: 33960544 PMCID: PMC8162594 DOI: 10.1111/jvim.16144] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 04/07/2021] [Accepted: 04/19/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Epilepsy is the most common chronic neurological disease in dogs that adversely affects the quality of life (QoL) of affected dogs and their owners. Research on epilepsy in dogs is expanding internationally, but where best to focus limited research time, funds, and expertise to achieve better outcomes for affected dogs and their owners has not been studied. OBJECTIVE To explore idiopathic epilepsy (IE) research priorities of owners of dogs with IE, general practice veterinarians, and veterinary neurologists. METHODS An international online survey was conducted in 2016 and repeated in 2020. Participants rated the absolute importance and relative rank of 18 areas of IE research, which were compared between groups and time points. RESULTS Valid responses were received from 414 respondents in 2016 and 414 respondents in 2020. The development of new anti-seizure drugs (ASD) and improving the existing ASD management were considered the most important research priorities. Areas of research with increasing priority between 2016 and 2020 included non-ASD management, with the greatest potential seen in behavioral and dietary-based interventions. Disagreements in priorities were identified between groups; owners prioritized issues that impacted their and their dog's QoL, for example, adverse effects and comorbidities, whereas general practitioner vets and neurologists prioritized clinical issues and longer-term strategies to manage or prevent IE, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE Ensuring that voices of owners are heard in the planning of future research should be a broader goal of veterinary medicine, to target research efforts toward areas most likely to improve the QoL of the dog-owner dyad.
Collapse
Affiliation(s)
| | - Holger Andreas Volk
- Department of Clinical Science and ServicesRoyal Veterinary CollegeHertfordshireUK
- Department of Small Animal Medicine and SurgeryUniversity of Veterinary Medicine HannoverHannoverGermany
| | | |
Collapse
|
6
|
Zilli J, Kressin M, Schänzer A, Kampschulte M, Schmidt MJ. Partial cortico-hippocampectomy in cats, as therapy for refractory temporal epilepsy: A descriptive cadaveric study. PLoS One 2021; 16:e0244892. [PMID: 33449929 PMCID: PMC7810294 DOI: 10.1371/journal.pone.0244892] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 12/17/2020] [Indexed: 11/18/2022] Open
Abstract
Cats, similar to humans, are known to be affected by hippocampal sclerosis (HS), potentially causing antiepileptic drug (AED) resistance. HS can occur as a consequence of chronic seizure activity, trauma, inflammation, or even as a primary disease. In humans, temporal lobe resection is the standardized therapy in patients with refractory temporal lobe epilepsy (TLE). The majority of TLE patients are seizure free after surgery. Therefore, the purpose of this prospective cadaveric study is to establish a surgical technique for hippocampal resection in cats as a treatment for AED resistant seizures. Ten cats of different head morphology were examined. Pre-surgical magnetic resonance imaging (MRI) and computed tomography (CT) studies of the animals’ head were carried out to complete 3D reconstruction of the head, brain, and hippocampus. The resected hippocampal specimens and the brains were histologically examined for tissue injury adjacent to the hippocampus. The feasibility of the procedure, as well as the usability of the removed specimen for histopathological examination, was assessed. Moreover, a micro-CT (mCT) examination of the brain of two additional cats was performed in order to assess temporal vasculature as a reason for possible intraoperative complications. In all cats but one, the resection of the temporal cortex and the hippocampus were successful without any evidence of traumatic or vascular lesions in the surrounding neurovascular structures. In one cat, the presence of mechanical damage (a fissure) of the thalamic surface was evident in the histopathologic examination of the brain post-resection. All hippocampal fields and the dentate gyrus were identified in the majority of the cats via histological examination. The study describes a new surgical approach (partial temporal cortico-hippocampectomy) offering a potential treatment for cats with clinical and diagnostic evidence of temporal epilepsy which do not respond adequately to the medical therapy.
Collapse
Affiliation(s)
- Jessica Zilli
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Giessen, Germany
- * E-mail:
| | - Monika Kressin
- Institute for Veterinary Anatomy, Histology and Embryology, Justus-Liebig-University, Giessen, Germany
| | - Anne Schänzer
- Institute of Neuropathology, Justus-Liebig-University, Giessen, Germany
| | | | - Martin J. Schmidt
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Giessen, Germany
| |
Collapse
|
7
|
Huaijantug S, Theeraphun W, Suwanna N, Thongpraparn T, Chanachai R, Aumarm W. Localization of cerebral hypoperfusion in dogs with refractory and non-refractory epilepsy using [99mTc] ethyl cysteinate dimer and single photon emission computed tomography. J Vet Med Sci 2020; 82:553-558. [PMID: 32188799 PMCID: PMC7273607 DOI: 10.1292/jvms.19-0372] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To evaluate the localization of functional deficit area in epileptogenic zones of the brain in seven refractory and seven non-refractory epilepsy dogs using technetium 99m labeled with
ethyl cysteinate dimer and interictal single photon emission computed tomography [99mTc-ECD SPECT] co-registration with Magnetic Resonance Imaging (MRI). Regions showing perfusion
deficits in the SPECT images were analyzed by using the standard semiquantitative evaluation method to compare the level of cortical perfusion to the maximum number of counts within the
cerebellum (max C), considered the area of reference. This study showed that SPECT imaging revealed abnormalities in several regions of the brain in both epilepsy groups. The refractory
epilepsy dogs showed more frequency area of hypoperfusion in temporal lobe than non-refractory group with not statistically significance (P=0.28). The result suggests the
lesion in temporal might be relevance with refractory epilepsy in canine patients.
Collapse
Affiliation(s)
- Somkiat Huaijantug
- Department of Companion Animals Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Jatujak, Bangkok, 10900, Thailand.,Department of Clinical Sciences and Public Health, Faculty of Veterinary Science, Mahidol University, Nakhon Pathom, 73170, Thailand
| | - Wuttiwong Theeraphun
- Department of Companion Animals Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Jatujak, Bangkok, 10900, Thailand
| | - Nirut Suwanna
- Department of Companion Animals Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Jatujak, Bangkok, 10900, Thailand
| | - Thanapong Thongpraparn
- Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Rujaporn Chanachai
- Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Waraporn Aumarm
- Department of Companion Animals Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Jatujak, Bangkok, 10900, Thailand
| |
Collapse
|
8
|
A double-blinded randomised dietary supplement crossover trial design to investigate the short-term influence of medium chain fatty acid (MCT) supplement on canine idiopathic epilepsy: study protocol. BMC Vet Res 2019; 15:181. [PMID: 31146740 PMCID: PMC6543566 DOI: 10.1186/s12917-019-1915-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 05/14/2019] [Indexed: 01/23/2023] Open
Abstract
Background Epilepsy is the most common brain disease in dogs. Recently, diets have been reported to have a positive impact on seizure activity and behaviour in various species including dogs with idiopathic epilepsy (IE). Historically, classic high fat ketogenic diets (KD) and medium chain triglycerides (MCT) KD have been successfully used to manage drug-resistant epilepsy. Similarly, an MCT enriched diet has been shown to improve seizure control and behavioural comorbidities in some dogs with IE. However, it is unknown whether an MCT dietary supplement (DS) may provide similar positive effects. Methods A 6-month prospective, randomised, double-blinded, placebo-controlled, crossover, multicentre dietary trial is designed comparing a 9% metabolic energy based calculated medium-chain triglyceride (MCT) oil supplement to a conventional ‘control’ DS. Only dogs which will have an International Veterinary Epilepsy Task Force Tier II level like diagnosis of IE which satisfied the following inclusion criteria are included: age between 6 months and ≤ 12 years; weighing between 4 and ≤ 65 kg; unremarkable interictal neurological examinations; no clinically significant findings on routine laboratory diagnostics; unremarkable brain MRI scan; have had at least 3 seizures in the previous 3 months prior to enrolment; treated with at least one ASD and being classified as resistant. All dogs are fed initially for 90 ± 2 days with either the control oil or the MCT oil alongside their normal diet, followed by 97 ± 2 days with the other supplement including a 7-day washout period. Overall, the aim is to recruit thirty-six patients at five different centres and to investigate the effect of MCTs as DS on seizure activity, tolerability, behavioural comorbidities and quality of life (QoL). Discussion Dietary interventions are rarely studied in a standardised form in veterinary medicine. The background diet, the cohort of animals and ASD received is standardised in this prospective diet trial to ensure representative data about the potential effect of MCT DS. If the study data confirms former findings, this would provide further evidence for the efficacy of MCTs as a management option for canine epilepsy. This publication should offer a repository of trial conditions and variable description with forecasted statistical analysis. Electronic supplementary material The online version of this article (10.1186/s12917-019-1915-8) contains supplementary material, which is available to authorized users.
Collapse
|
9
|
Czerwik A, Płonek M, Podgórski P, Wrzosek M. Comparison of electroencephalographic findings with hippocampal magnetic resonance imaging volumetry in dogs with idiopathic epilepsy. J Vet Intern Med 2018; 32:2037-2044. [PMID: 30325068 PMCID: PMC6271325 DOI: 10.1111/jvim.15323] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 07/13/2018] [Accepted: 08/15/2018] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND In humans, temporal lobe epilepsy (TLE), is a type of focal epilepsy occurring mainly in the mesial TLE (mTLE), commonly associated with hippocampal sclerosis (HS). OBJECTIVES According to recent studies, TLE might also occur in dogs and could be associated with hippocampal atrophy (HA)/HS. To date, hippocampal lesions have not been correlated with electroencephalographic (EEG) findings in epileptic dogs. ANIMALS An EEG examination, brain magnetic resonance imaging, and volumetric assessment of the hippocampus were performed in 16 nonepileptic and 41 epileptic dogs. METHODS In this retrospective study, the presence and localization of EEG-defined epileptiform discharges (EDs) was blindly evaluated. The hippocampus was measured and assessed for unilateral atrophy. The results of EEG and volumetric findings were correlated to determine whether the functional epileptic focus is equivalent to structural changes. RESULTS The median hippocampal asymmetric ratio (AR) in epileptic dogs was significantly greater than in the control group (P < .001). Using a cut-off threshold AR of >6%, 56% (23/41) of the dogs were characterized with unilateral HA. Of those animals, 35% (8/23) had EDs in the temporal leads and 26% (6/23) had no EDs. In 88% (7/8) of dogs with EDs in the temporal leads that had unilateral HA, the EDs correlated with the side of the decreased hippocampal volume. CONCLUSIONS AND CLINICAL IMPORTANCE The results indicate an association between the presence of EDs detectable on EEG and a decrease in the unilateral hippocampal volume in some cases of canine idiopathic epilepsy that might reflect features of human mTLE.
Collapse
Affiliation(s)
- Adriana Czerwik
- Department of Internal Medicine and Clinic for Horses, Dogs and Cats, The Faculty of Veterinary MedicineWrocław University of Environmental and Life SciencesWrocławPoland
| | - Marta Płonek
- Center of Experimental Diagnostics and Innovative Biomedical Technologies, The Faculty of Veterinary MedicineWrocław University of Environmental and Life SciencesWrocławPoland
| | - Przemyslaw Podgórski
- Department of General Radiology, Interventional Radiology and NeuroradiologyWrocław Medical UniversityWrocławPoland
| | - Marcin Wrzosek
- Department of Internal Medicine and Clinic for Horses, Dogs and Cats, The Faculty of Veterinary MedicineWrocław University of Environmental and Life SciencesWrocławPoland
| |
Collapse
|
10
|
Investigating owner use of dietary supplements in dogs with idiopathic epilepsy. Res Vet Sci 2018; 119:276-284. [PMID: 30064067 DOI: 10.1016/j.rvsc.2018.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 06/01/2018] [Accepted: 07/21/2018] [Indexed: 12/29/2022]
Abstract
Epilepsy is the most common chronic neurological disorder in dogs. Some diets have been shown to have a positive impact upon the seizure activity in dogs with idiopathic epilepsy (IE), while other diets and dietary supplements (DS), although marketed as providing health benefits, lack conclusive scientific evidence on their actual beneficial effects. A web-based owner questionnaire was designed to assess how and why owners of dogs with IE use different dietary regimes and DS. The study cohort, with 297 valid responses, consisted mainly of pure-breed (82.5%) male neutered (52.9%) dogs. Over two-thirds of owners (67.7%) changed their dog's diet after their dog received a diagnosis of IE. Nearly half of the owners (45.8%) reported giving DS, the most common being coconut oil or derived medium-chain triglyceride oil (71.3%). Some owner justifications of DS use included improvement of seizure frequency (88.2%), seizure severity (61.8%) and protection from potential drug side effects (62.5%). Many owners give DS to their dog with IE. The pharmacokinetic properties of anti-epileptic drugs, such as efficacy, absorption and clearance can be influenced by other medications, diets and possibly by DS. We propose that use of DS should be considered and monitored by veterinary surgeons in epilepsy management.
Collapse
|
11
|
Metabolic perturbations associated with the consumption of a ketogenic medium-chain TAG diet in dogs with idiopathic epilepsy. Br J Nutr 2018; 120:484-490. [PMID: 30001753 PMCID: PMC6137430 DOI: 10.1017/s0007114518001617] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Consumption of diets containing medium-chain TAG (MCT) has been shown to confer neuroprotective effects. We aim to identify the global metabolic perturbations associated with consumption of a ketogenic diet (medium-chain TAG diet (MCTD)) in dogs with idiopathic epilepsy. We used ultra-performance liquid chromatography-MS (UPLC-MS) to generate metabolic and lipidomic profiles of fasted canine serum and made comparisons between the MCTD and standardised placebo diet phases. We identified metabolites that differed significantly between diet phases using metabolite fragmentation profiles generated by tandem MS (UPLC-MS/MS). Consumption of the MCTD resulted in significant differences in serum metabolic profiles when compared with the placebo diet, where sixteen altered lipid metabolites were identified. Consumption of the MCTD resulted in reduced abundances of palmitoylcarnitine, octadecenoylcarnitine, stearoylcarnitine and significant changes, both reduced and increased abundances, of phosphatidylcholine (PC) metabolites. There was a significant increase in abundance of the saturated C17 : 0 fatty acyl moieties during the MCTD phase. Lysophosphatidylcholine (17 : 0) (P=0·01) and PC (17:0/20:4) (P=0·03) were both significantly higher in abundance during the MCTD. The data presented in this study highlight global changes in lipid metabolism, and, of particular interest, in the C17 : 0 moieties, as a result of MCT consumption. Elucidating the global metabolic response of MCT consumption will not only improve the administration of current ketogenic diets for neurological disease models but also provides new avenues for research to develop better diet therapies with improved neuroprotective efficacies. Future studies should clarify the involvement and importance of C17 : 0 moieties in endogenous MCT metabolic pathways.
Collapse
|
12
|
Wang YQ, Zhang MQ, Li R, Qu WM, Huang ZL. The Mutual Interaction Between Sleep and Epilepsy on the Neurobiological Basis and Therapy. Curr Neuropharmacol 2018; 16:5-16. [PMID: 28486925 PMCID: PMC5771383 DOI: 10.2174/1570159x15666170509101237] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Revised: 07/11/2017] [Accepted: 04/27/2017] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Sleep and epilepsy are mutually related in a complex, bidirectional manner. However, our understanding of this relationship remains unclear. RESULTS The literatures of the neurobiological basis of the interactions between sleep and epilepsy indicate that non rapid eye movement sleep and idiopathic generalized epilepsy share the same thalamocortical networks. Most of neurotransmitters and neuromodulators such as adenosine, melatonin, prostaglandin D2, serotonin, and histamine are found to regulate the sleep-wake behavior and also considered to have antiepilepsy effects; antiepileptic drugs, in turn, also have effects on sleep. Furthermore, many drugs that regulate the sleep-wake cycle can also serve as potential antiseizure agents. The nonpharmacological management of epilepsy including ketogenic diet, epilepsy surgery, neurostimulation can also influence sleep. CONCLUSION In this paper, we address the issues involved in these phenomena and also discuss the various therapies used to modify them.
Collapse
Affiliation(s)
| | | | - Rui Li
- Department of Pharmacology and Shanghai Key Laboratory of Bioactive Small Molecules, School of Basic Medical Sciences; State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation
Center for Brain Science, Fudan University, Shanghai200032, P.R. China
| | - Wei-Min Qu
- Department of Pharmacology and Shanghai Key Laboratory of Bioactive Small Molecules, School of Basic Medical Sciences; State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation
Center for Brain Science, Fudan University, Shanghai200032, P.R. China
| | - Zhi-Li Huang
- Department of Pharmacology and Shanghai Key Laboratory of Bioactive Small Molecules, School of Basic Medical Sciences; State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation
Center for Brain Science, Fudan University, Shanghai200032, P.R. China
| |
Collapse
|
13
|
Xia J, Li CY, Wang H, Zhang QM, Han ZM. Therapeutic effects of scoparone on pilocarpine (Pilo)-induced seizures in mice. Biomed Pharmacother 2017; 97:1501-1513. [PMID: 29793313 DOI: 10.1016/j.biopha.2017.09.127] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/24/2017] [Accepted: 09/24/2017] [Indexed: 02/07/2023] Open
Abstract
Epilepsy is a common and devastating neurological disorder. Inflammatory processes and apoptosis in brain tissue have been reported in human epilepsy. Scoparone (6,7-dimethoxycoumarin) is an important chemical substance, which has multiple beneficial activities, including antitumor, anti-inflammatory and anti-coagulant properties. In our present study, we attempted to investigate if scoparone could attenuate seizures-induced blood brain barrier breakdown, inflammation and apoptosis. Pilocarpine (Pilo) and methylscopolamine were used to establish acute seizure animal model. Scoparone suppressed the leakage of blood brain barrier, inflammation and apoptosis. In hippocampus and cortex, the expression of inflammation-associated molecules, such as chemokine (CXC motif) ligand 1 (CXCL-1), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), IL-6, hypoxia-inducible factor 1α (HIF-1α), and monocyte chemoattractant protein-1 (MCP-1), were reduced by scoparone through inactivating toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) pathway. Scoparone reduced apoptotic levels in hippocampus by TUNEL analysis, along with decreased Caspase-3 and PARP cleavage. In addition, phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway in Pilo-induced acute seizures was also inactivated by scoparone. In vitro, we confirmed that scoparone inhibited LPS-caused astrocytes activation as proved by the reduced glial fibrillary acidic protein (GFAP) levels, inflammation and apoptosis, which were at least partly dependent on AKT suppression. The results above indicated that scoparone could relieve pilocarpine (Pilo)-induced seizures against neural cell inflammation and apoptosis.
Collapse
Affiliation(s)
- Jie Xia
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, PR China
| | - Cheng-Yan Li
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, PR China.
| | - Hui Wang
- Department of Anesthesiology, Renhe Hospital of China Three Gorges University, Yichang, Hubei 443002, PR China
| | - Qi-Mei Zhang
- Institute of Neurology, China Three Gorges University, Yichang, Hubei 443002, PR China
| | - Zhong-Mou Han
- Institute of Neurology, China Three Gorges University, Yichang, Hubei 443002, PR China
| |
Collapse
|
14
|
Hartmann A, Sager S, Failing K, Sparenberg M, Schmidt MJ. Diffusion-weighted imaging of the brains of dogs with idiopathic epilepsy. BMC Vet Res 2017; 13:338. [PMID: 29141638 PMCID: PMC5688626 DOI: 10.1186/s12917-017-1268-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 11/10/2017] [Indexed: 02/07/2023] Open
Abstract
Background Idiopathic epilepsy is one of the most common neurological disorders in dogs. Unfortunately, up to 30% of dogs with idiopathic epilepsy show no improvement under antiepileptic drug treatment. Diffusion-weighted imaging is used in human medicine to identify epileptogenic foci in the brain to allow for more invasive treatments such as deep brain stimulation or surgical removal. The aim of this study was to ass the feasibility of interictal diffusion-weighted MRI in dogs and to evaluate the distribution of diffusion in the brains of dogs with idiopathic epilepsy (IE) and to compare these values to previously published values from healthy beagle dogs. Client-owned dogs with the final diagnosis of IE were included in this study. MRI examination was carried out using a 1.0Tesla superconductive magnet. Diffusion-weighted images using a single shot echo planar imaging sequence (SSh-EPI) with a b value of b = 0 s/mm2 and b = 800 s/mm2 were acquired in a dorsal and transverse plane with diffusion gradients in all three planes (x-, y- and z-plane). An ADC (apparent diffusion coefficient) map of the isometric image of each acquired slice was generated. Regions of interest (ROIs) were manually drawn around the caudate nucleus, the thalamus, the piriform lobe including the amygdala, the hippocampus, the semioval center and the temporal cerebral cortex by one of the authors. ROI drawings were repeated 5 times at different time points to assess intra-obersver variability. A multi-way mixed-model analysis of variance (ANOVA) and two-way ANOVA were used during statistical analysis. A p value of p < 0.05 was considered significant. Results Dogs with IE showed a significantly increased ADC in the amygdala within the piriform lobe and in the semioval center (p < 0.05) compared with the healthy control group. Conclusion Changes in the piriform lobe in cases of epilepsy are reported infrequently in human and veterinary medicine. Similar to our results, ADC changes in the interictal phase usually include an increase in ADC due to cell loss and increased intercellular spaces. Diffusion MRI might be a promising technique for the examination of canine epileptic patients lacking other gross neuromorphological abnormalities.
Collapse
Affiliation(s)
- Antje Hartmann
- Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Länggassstraße 128, 3012, Bern, Switzerland.
| | - Steffen Sager
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University Giessen, Frankfurter Straße 108, 35392, Giessen, Germany
| | - Klaus Failing
- Unit for Biomathematics and Data Processing Faculty of Veterinary Medicine Justus Liebig-University, Frankfurter Straße 95, 35392, Giessen, Germany
| | - Marion Sparenberg
- Unit for Biomathematics and Data Processing Faculty of Veterinary Medicine Justus Liebig-University, Frankfurter Straße 95, 35392, Giessen, Germany
| | - Martin J Schmidt
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University Giessen, Frankfurter Straße 108, 35392, Giessen, Germany
| |
Collapse
|
15
|
Martlé V, Van Ham LML, Boon P, Caemaert J, Tshamala M, Vonck K, Raedt R, Polis I, Bhatti S. Vagus Nerve Stimulator Placement in Dogs: Surgical Implantation Technique, Complications, Long-Term Follow-Up, and Practical Considerations. Vet Surg 2016; 45:71-8. [PMID: 26731597 DOI: 10.1111/vsu.12427] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To describe a modified implantation procedure of a vagus nerve stimulation (VNS) device in dogs and to report short- and long-term complications. STUDY DESIGN Descriptive, experimental study. ANIMALS Healthy, adult Beagle dogs (n = 10). METHODS A VNS Therapy(®) System was implanted in the left cervical region of anesthetized dogs. During and within 48 hours after surgery, electrocardiography (ECG) and impedance testing of the system were performed. Dogs were monitored daily and the impedance of the system was determined regularly until VNS devices were surgically removed 3 years after implantation. RESULTS The implantation procedure was successful in all dogs without intraoperative complications. ECG monitoring and impedance tests were within normal limits during and within 48 hours after surgery. Postoperative seroma formation was common (70%). One dog developed an irreversible Horner's syndrome leading to removal of the device 5 months after implantation. Another dog developed trauma-induced damage of the lead requiring surgical revision. The device could be safely removed in all dogs; however, electrodes were left in place to avoid nerve damage. At removal, the anchor tether was dislodged in 40% of dogs and the lead was twisted in 50% of dogs. CONCLUSION Implantation of a VNS Therapy(®) System is safe and feasible in dogs; however, seroma formation, twisting of the lead, and dislodgement of the anchor tether were common. Practical improvements in the technique include stable device placement, use of a compression bandage, and exercise restriction. Regular evaluation of lead impedance is important, as altered values can indicate serious complications.
Collapse
Affiliation(s)
- Valentine Martlé
- Faculty of Veterinary Medicine, Department of Small Animal Medicine and Clinical Biology, Ghent University, Merelbeke, Belgium
| | - Luc M L Van Ham
- Faculty of Veterinary Medicine, Department of Small Animal Medicine and Clinical Biology, Ghent University, Merelbeke, Belgium
| | - Paul Boon
- Faculty of Medicine and Health Sciences, Department of Neurology
| | - Jacques Caemaert
- Faculty of Medicine and Health Sciences, Department of Neurosurgery, Ghent University Hospital, Ghent, Belgium
| | - Mulenda Tshamala
- Faculty of Veterinary Medicine, Department of Small Animal Medicine and Clinical Biology, Ghent University, Merelbeke, Belgium
| | - Kristl Vonck
- Faculty of Medicine and Health Sciences, Department of Neurology
| | - Robrecht Raedt
- Faculty of Medicine and Health Sciences, Department of Neurology
| | - Ingeborgh Polis
- Faculty of Veterinary Medicine, Department of Small Animal Medicine and Clinical Biology, Ghent University, Merelbeke, Belgium
| | - Sofie Bhatti
- Faculty of Veterinary Medicine, Department of Small Animal Medicine and Clinical Biology, Ghent University, Merelbeke, Belgium
| |
Collapse
|
16
|
Diagnostic techniques to detect the epileptogenic zone: Pathophysiological and presurgical analysis of epilepsy in dogs and cats. Vet J 2016; 215:64-75. [DOI: 10.1016/j.tvjl.2016.03.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 02/24/2016] [Accepted: 03/05/2016] [Indexed: 12/17/2022]
|
17
|
Podell M, Volk HA, Berendt M, Löscher W, Muñana K, Patterson EE, Platt SR. 2015 ACVIM Small Animal Consensus Statement on Seizure Management in Dogs. J Vet Intern Med 2016; 30:477-90. [PMID: 26899355 PMCID: PMC4913615 DOI: 10.1111/jvim.13841] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 01/18/2016] [Accepted: 01/18/2016] [Indexed: 11/27/2022] Open
Abstract
This report represents a scientific and working clinical consensus statement on seizure management in dogs based on current literature and clinical expertise. The goal was to establish guidelines for a predetermined, concise, and logical sequential approach to chronic seizure management starting with seizure identification and diagnosis (not included in this report), reviewing decision‐making, treatment strategies, focusing on issues related to chronic antiepileptic drug treatment response and monitoring, and guidelines to enhance patient response and quality of life. Ultimately, we hope to provide a foundation for ongoing and future clinical epilepsy research in veterinary medicine.
Collapse
Affiliation(s)
- M Podell
- Medvet Chicago, Medical and Cancer Centers for Pets, Chicago, IL.,Department of Neurosurgery, Pritzker School of Medicine, The University of Chicago, Chicago, IL
| | - H A Volk
- Department of Clinical Sciences and Services, Small Animal Medicine and Surgery Group, The Royal Veterinary College, Hatfield, Hertfordshire, UK
| | - M Berendt
- Department of Veterinary and Clinical Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - W Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - K Muñana
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC
| | - E E Patterson
- Department of Veterinary Clinical Sciences, University of Minnesota College of Veterinary Medicine, St. Paul, MN
| | - S R Platt
- Department of Small Animal Medicine & Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA
| |
Collapse
|
18
|
Abstract
Despite appropriate antiepileptic drug treatment, approximately one-third of humans and dogs with epilepsy continue experiencing seizures, emphasising the importance for new treatment strategies to improve the quality of life of people or dogs with epilepsy. A 6-month prospective, randomised, double-blinded, placebo-controlled cross-over dietary trial was designed to compare a ketogenic medium-chain TAG diet (MCTD) with a standardised placebo diet in chronically antiepileptic drug-treated dogs with idiopathic epilepsy. Dogs were fed either MCTD or placebo diet for 3 months followed by a subsequent respective switch of diet for a further 3 months. Seizure frequency, clinical and laboratory data were collected and evaluated for twenty-one dogs completing the study. Seizure frequency was significantly lower when dogs were fed the MCTD (2·31/month, 0-9·89/month) in comparison with the placebo diet (2·67/month, 0·33-22·92/month, P=0·020); three dogs achieved seizure freedom, seven additional dogs had ≥50 % reduction in seizure frequency, five had an overall <50 % reduction in seizures (38·87 %, 35·68-43·27 %) and six showed no response. Seizure day frequency were also significantly lower when dogs were fed the MCTD (1·63/month, 0-7·58/month) in comparison with the placebo diet (1·69/month, 0·33-13·82/month, P=0·022). Consumption of the MCTD also resulted in significant elevation of blood β-hydroxybutyrate concentrations in comparison with placebo diet (0·071 (sd 0·035) v. 0·053 (sd 0·028) mmol/l, P=0·028). There were no significant changes in serum concentrations of glucose (P=0·903), phenobarbital (P=0·422), potassium bromide (P=0·404) and weight (P=0·300) between diet groups. In conclusion, the data show antiepileptic properties associated with ketogenic diets and provide evidence for the efficacy of the MCTD used in this study as a therapeutic option for epilepsy treatment.
Collapse
|
19
|
Martlé V, Raedt R, Waelbers T, Smolders I, Vonck K, Boon P, Van Ham L, Duchateau L, Bhatti S. The Effect of Vagus Nerve Stimulation on CSF Monoamines and the PTZ Seizure Threshold in Dogs. Brain Stimul 2015; 8:1-6. [DOI: 10.1016/j.brs.2014.07.032] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 05/31/2014] [Accepted: 07/13/2014] [Indexed: 11/25/2022] Open
|
20
|
Clinical risk factors associated with anti-epileptic drug responsiveness in canine epilepsy. PLoS One 2014; 9:e106026. [PMID: 25153799 PMCID: PMC4143335 DOI: 10.1371/journal.pone.0106026] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Accepted: 07/29/2014] [Indexed: 11/19/2022] Open
Abstract
The nature and occurrence of remission, and conversely, pharmacoresistance following epilepsy treatment is still not fully understood in human or veterinary medicine. As such, predicting which patients will have good or poor treatment outcomes is imprecise, impeding patient management. In the present study, we use a naturally occurring animal model of pharmacoresistant epilepsy to investigate clinical risk factors associated with treatment outcome. Dogs with idiopathic epilepsy, for which no underlying cause was identified, were treated at a canine epilepsy clinic and monitored following discharge from a small animal referral hospital. Clinical data was gained via standardised owner questionnaires and longitudinal follow up data was gained via telephone interview with the dogs’ owners. At follow up, 14% of treated dogs were in seizure-free remission. Dogs that did not achieve remission were more likely to be male, and to have previously experienced cluster seizures. Seizure frequency or the total number of seizures prior to treatment were not significant predictors of pharmacoresistance, demonstrating that seizure density, that is, the temporal pattern of seizure activity, is a more influential predictor of pharmacoresistance. These results are in line with clinical studies of human epilepsy, and experimental rodent models of epilepsy, that patients experiencing episodes of high seizure density (cluster seizures), not just a high seizure frequency pre-treatment, are at an increased risk of drug-refractoriness. These data provide further evidence that the dog could be a useful naturally occurring epilepsy model in the study of pharmacoresistant epilepsy.
Collapse
|
21
|
Jeffery ND. Canine epilepsy: in search of a fitting end. Vet J 2013; 199:311-2. [PMID: 24440441 DOI: 10.1016/j.tvjl.2013.11.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 11/25/2013] [Indexed: 10/25/2022]
Affiliation(s)
- Nick D Jeffery
- College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
| |
Collapse
|