1
|
Pakozdy A, Halasz P, Klang A, Lörincz BA, Schmidt MJ, Glantschnigg-Eisl U, Binks S. Temporal lobe epilepsy in cats. Vet J 2023; 291:105941. [PMID: 36549606 DOI: 10.1016/j.tvjl.2022.105941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 12/02/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022]
Abstract
In recent years there has been increased attention to the proposed entity of feline temporal lobe epilepsy (TLE). Epileptic discharges in certain parts of the temporal lobe elicit very similar semiology, which justifies grouping these epilepsies under one name. Furthermore, feline TLE patients tend to have histopathological changes within the temporal lobe, usually in the hippocampus. The initial aetiology is likely to be different but may result in hippocampal necrosis and later hippocampal sclerosis. The aim of this article was not only to summarise the clinical features and the possible aetiology, but also being work to place TLE within the veterinary epilepsy classification. Epilepsies in cats, similar to dogs, are classified based on the aetiology into idiopathic epilepsy, structural epilepsy and unknown cause. TLE seems to be outside of this classification, as it is not an aetiologic category, but a syndrome, associated with a topographic affiliation to a certain anatomical brain structure. Magnetic resonance imaging, histopathologic aspects and current medical therapeutic considerations will be summarised, and emerging surgical options are discussed.
Collapse
Affiliation(s)
- Akos Pakozdy
- University Clinic for Small Animals, University of Veterinary Medicine, Vienna, Austria.
| | - Peter Halasz
- Institute of Experimental Medicine, Budapest, Hungary
| | - Andrea Klang
- Institute of Pathology, University of Veterinary Medicine, Austria
| | - Borbala A Lörincz
- Clinic of Diagnostic Imaging, University of Veterinary Medicine Vienna, Austria
| | - Martin J Schmidt
- Department of Veterinary Clinical Sciences, Small Animal Clinic-Neurosurgery, Neuroradiology and Clinical Neurology, Justus-Liebig-University, Germany
| | | | - Sophie Binks
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, UK
| |
Collapse
|
2
|
Hasegawa D, Kanazono S, Chambers JK, Uchida K. Neurosurgery in feline epilepsy, including clinicopathology of feline epilepsy syndromes. Vet J 2022; 290:105928. [PMID: 36347391 DOI: 10.1016/j.tvjl.2022.105928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 11/04/2022] [Accepted: 11/04/2022] [Indexed: 11/07/2022]
Abstract
Feline epilepsy is treated with antiseizure medications, which achieves fair to good seizure control. However, a small subset of feline patients with drug-resistant epilepsy requires alternative therapies. Furthermore, approximately 50 % of cats with epileptic seizures are diagnosed with structural epilepsy with or without hippocampal abnormality and may respond to surgical intervention. The presence of hippocampal pathology and intracranial tumors is a key point to consider for surgical treatment. This review describes feline epilepsy syndrome and epilepsy-related pathology, and discusses the indications for and availability of neurosurgery, including lesionectomy, temporal lobectomy with hippocampectomy, and corpus callosotomy, for cats with different epilepsy types.
Collapse
Affiliation(s)
- Daisuke Hasegawa
- Laboratory of Veterinary Radiology, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan; The Research Center for Animal Life Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan.
| | - Shinichi Kanazono
- Neurology and Neurosurgery Service, Veterinary Specialists and Emergency Center, 815 Ishigami, Kawaguchi, Saitama 333-0823, 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
| |
Collapse
|
3
|
Zilli J, Schänzer A, Büttner K, Kressin M, Schmidt MJ. Quantitative and qualitative evaluation of the hippocampal cytoarchitecture in adult cats with regard to the pathological diagnosis of hippocampal sclerosis. PLoS One 2022; 17:e0268010. [PMID: 35560321 PMCID: PMC9106214 DOI: 10.1371/journal.pone.0268010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 04/20/2022] [Indexed: 11/18/2022] Open
Abstract
Cats are known to be affected by hippocampal sclerosis, potentially causing antiseizure drug(s) resistance. In order to lay the foundation for a standardized, systematic classification and diagnosis of this pathology in cats, this prospective study aimed at evaluating normal reference values of cellular densities and the cytoarchitecture of the feline hippocampus. Three transverse sections (head, body and tail) of each left hippocampus were obtained from 17 non-epileptic cats of different brachycephalic and mesocephalic breeds and age classes (range: 3–17 years). Histological (hematoxylin and eosin, Nissl) and immunohistochemical (NeuN, GFAP) staining was performed to investigate neuron and astroglial cell populations, as well as the layer thickness of the pyramidal cell layer and granule cell layer. Significant differences in neuronal density (in CA2-CA4 and the granule cell layer) and layer thickness (in CA1-CA3 and the granule cell layer) were evidenced throughout the longitudinal hippocampal axis (p<0.05); on the other hand, the astrocyte density did not differ. Moreover, reference ranges were defined for these parameters in the pyramidal cell layer and in the granule cell layer. The findings did not differ according to breed or age. In veterinary medicine these parameters have not been evaluated in cats so far. As surgical treatment may become a therapeutic option for cats with temporal lobe epilepsy, estimating normal values of the hippocampal cytoarchitecture will help in the standardized histopathological examination of resected hippocampal specimens to reach a diagnosis of hippocampal sclerosis.
Collapse
Affiliation(s)
- Jessica Zilli
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Giessen, Hessen, Germany
- * E-mail:
| | - Anne Schänzer
- Institute of Neuropathology, Justus-Liebig-University, Giessen, Hessen, Germany
| | - Kathrin Büttner
- Institute for Biomathematics, Justus-Liebig-University, Giessen, Hessen, Germany
| | - Monika Kressin
- Institute for Veterinary Anatomy, Histology and Embryology, Justus-Liebig-University, Giessen, Hessen, Germany
| | - Martin J. Schmidt
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Giessen, Hessen, Germany
| |
Collapse
|
4
|
Corpus Callosotomy in 3 Cavalier King Charles Spaniel Dogs with Drug-Resistant Epilepsy. Brain Sci 2021; 11:brainsci11111462. [PMID: 34827461 PMCID: PMC8615928 DOI: 10.3390/brainsci11111462] [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] [Received: 10/18/2021] [Revised: 11/02/2021] [Accepted: 11/02/2021] [Indexed: 12/13/2022] Open
Abstract
Corpus callosotomy (CC) is an established palliative surgery for human patients with drug-resistant epilepsy (DRE), especially those with generalized seizures and multiple or unknown epileptogenic focus. However, there are no reports to describe CC in canine patients with epilepsy. Three client-owned Cavalier King Charles Spaniels with DRE are included in this case series. In presurgical evaluations, an apparent epileptogenic zone was not detected in each dog and CC was conducted. Total CC was performed in one dog, whereas the other two received partial CC. One dog recovered from surgery without any complications, but died suddenly by an unknown cause at 10 h after surgery. For the other two dogs, postoperative evaluations including seizure outcomes, complications, and quality of life of the dogs and owners were assessed for at least 12 months. Both dogs showed a remarkable decrease in seizure frequency (averaged 80.3% reduction) and severity after surgery. The antiseizure medications were maintained, and not only the mentation and activity of the dogs, but also the quality of life of dogs and owners were improved postoperatively. Although technical improvement and more large-scale studies are needed, CC is a treatment option for dogs with DRE in veterinary medicine.
Collapse
|
5
|
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
|
6
|
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
|