In small breed dogs, enlarged ventricles of the brain are a common finding on magnetic resonance imaging (MRI). In humans, enlarged lateral ventricles are usually the consequence of mesencephalic aqueduct stenosis. Cerebrospinal fluid (CSF) velocity measurements indicating obstruction are lacking in dogs. Measure CSF velocity in small breed dogs with ventricular enlargement. Velocity of CSF in 17 small breed dogs with enlarged ventricles and 8 small breed dogs with normal-sized ventricles was measured by phase-contrast MRI at the mesencephalic aqueduct, foramen magnum (FM) and second cervical vertebra (C2). Peak systolic (PSV) and diastolic (PDV) velocity, peak velocity (PV), difference between peak systolic and diastolic velocity (DPV), average velocity (AV) and maximum average velocity (MAV) were measured. Dogs with enlarged ventricles had lower PDV, PV, AV, and MAV at the dorsal subarachnoid space of the FM compared with dogs without enlargement ( p  < 0.05). At the ventral subarachnoid space of FM, moderate decreases in PDV, PV, DPV, AV, and MAV were found with increasing severity of ventricular enlargement. Ventricular enlargement may be associated with or result in altered CSF flow dynamics, particularly decreased velocity at the craniocervical junction. This relationship may, in turn, reflect underlying structural changes, such as skull shape or craniocervical abnormalities. Therefore, enlarged ventricles in small breed dogs should be considered pathological findings.

AbstractBackgroundIn dogs with idiopathic epilepsy (IE), 33% develop resistance to conventional anti‐seizure medication (ASM) despite adequate treatment. In human medicine, an immune‐mediated etiology is suspected in a subset of ASM‐resistant patients with epilepsy and cerebrospinal fluid (CSF)‐specific immunoglobulin G (IgG)‐type oligoclonal bands (OCBs) have been detected. In dogs, cases of autoimmune encephalitis recently were reported. Neuroinflammation may provide an additional explanation for the lack of response of certain dogs with IE to ASM.HypothesisCerebrospinal fluid‐specific OCBs are found in a subgroup of dogs with ASM‐resistant IE.AnimalsEighty‐four dogs with IE were recruited from 3 referral centers and classified based on their response to ASM treatment (responsive, n = 56; resistant, n = 28).MethodsDetection of OCBs was performed using isoelectric focusing (IEF) followed by immunoblotting. Associations of CSF‐specific OCBs with seizure type, severity, and response to ASM were calculated using logistic regression models.ResultsThe overall frequency of CSF‐specific OCBs in dogs with IE was 15.5% (95% confidence interval [CI], 8.5%‐25%). In dogs with ASM‐resistant IE, 21.4% (6/28) had CSF‐specific OCBs compared with only 12.5% (7/56) in those responsive to ASM, but no evidence of an association was detected (odds ratio, 1.9; 95% CI, 0.57‐6.35; P = .29).Conclusions and Clinical ImportanceCerebrospinal fluid‐specific OCBs were detected in a subgroup of dogs with IE. This finding could indicate that intrathecal IgG synthesis as a sign of neuroinflammation may play a role in disease pathogenesis.

BACKGROUND:In small breed dogs, enlarged ventricles of the brain are a common finding on magnetic resonance imaging (MRI). In humans, enlarged lateral ventricles are usually the consequence of mesencephalic aqueduct stenosis. Cerebrospinal fluid (CSF) velocity measurements indicating obstruction are lacking in dogs. OBJECTIVES:Measure CSF velocity in small breed dogs with ventricular enlargement. ANIMALS:Velocity of CSF in 17 small breed dogs with enlarged ventricles and 8 small breed dogs with normal-sized ventricles was measured by phase-contrast MRI at the mesencephalic aqueduct, foramen magnum (FM) and second cervical vertebra (C2). METHODS:Peak systolic (PSV) and diastolic (PDV) velocity, peak velocity (PV), difference between peak systolic and diastolic velocity (DPV), average velocity (AV) and maximum average velocity (MAV) were measured. RESULTS:Dogs with enlarged ventricles had lower PDV, PV, AV, and MAV at the dorsal subarachnoid space of the FM compared with dogs without enlargement (p < 0.05). At the ventral subarachnoid space of FM, moderate decreases in PDV, PV, DPV, AV, and MAV were found with increasing severity of ventricular enlargement. CONCLUSION:Ventricular enlargement may be associated with or result in altered CSF flow dynamics, particularly decreased velocity at the craniocervical junction. This relationship may, in turn, reflect underlying structural changes, such as skull shape or craniocervical abnormalities. Therefore, enlarged ventricles in small breed dogs should be considered pathological findings.

Objectives Window entrapment in cats can lead to reduced blood flow to the spinal cord, muscles and nerves, resulting in ischaemic neuromyelomyopathy. The severity and duration of entrapment greatly influence clinical and neurological outcomes, as well as prognosis. The aim of the present retrospective multicentric study (2005–2022) was to describe clinical, neurological and selected clinicopathological findings, as well as the outcome of cats trapped in bottom-hung windows, presented to both first-opinion and referral-only clinics. Methods The study included cats with detailed clinical and neurological evaluations at admission, along with at least one of the following biochemical parameters: creatine kinase (CK), aspartate transaminase (AST), alanine aminotransferase (ALT) activities, urea and/or creatinine. Clinical and neurological parameters evaluated in the study included rectal temperature, femoral pulse, gait, urinary bladder function, tail function and survival to discharge. Odds ratios (ORs) were calculated for survival and each clinical, neurological and biochemical variable. Results Of the 70 cats that met the inclusion criteria, only seven (10%) died or were euthanased during hospitalisation. Nevertheless, with the available data, we found evidence of an association between clinical and neurological status and survival, with tail function being the strongest association. Cats lacking tail sensation, motor function and/or tonus were more likely to die than cats with normal tail function or only mild abnormalities (OR = 24). Similarly, cats with severe hypothermia or an absent femoral pulse were less likely to survive (OR = 12.75 and 7.5, respectively). In this sample (with a relatively low number of deaths), we did not find evidence of an association between CK, AST and ALT activity with survival. However, the only two cats with severe increases in creatinine died. Conclusions and relevance Assessment of gait, urinary bladder function, femoral pulse, rectal temperature and particularly tail function is promising for predicting outcomes in cats with window entrapment trauma.

Abstract Background Electroencephalography (EEG) recording protocols have been standardized for humans. Although the utilization of techniques in veterinary medicine is increasing, a standard protocol has not yet been established. Hypothesis Assessment of a sedation‐awakening EEG protocol in dogs. Animals Electroencephalography examination was performed in a research colony of 6 nonepileptic dogs (control [C]) and 12 dogs with epilepsy admitted to the clinic because of the epileptic seizures. Methods It was a prospective study with retrospective control. Dogs with epilepsy were divided into 2 equal groups, wherein EEG acquisition was performed using a “sedation” protocol (IE‐S, n = 6) and a “sedation‐awakening” protocol (IE‐SA, n = 6). All animals were sedated using medetomidine. In IE‐SA group, sedation was reversed 5 minutes after commencing the EEG recording by injecting atipamezole IM. Type of background activity (BGA) and presence of EEG‐defined epileptiform discharges (EDs) were evaluated blindly. Statistical significance was set at P > 0.05. Results Epileptiform discharges were found in 1 of 6 of the dogs in group C, 4 of 6 of the dogs in IE‐S group, and 5 of 6 of the dogs in IE‐SA group. A significantly greater number of EDs (spikes, P = .0109; polyspikes, P = .0109; sharp waves, P = .01) were detected in Phase 2 in animals subjected to the “sedation‐awakening” protocol, whereas there was no statistically significant greater number of discharges in sedated animals. Conclusions and Clinical Importance A “sedation‐awakening” EEG protocol could be of value for ambulatory use if repeated EEG recordings and monitoring of epilepsy in dogs is needed.

Two female (FL 1, FL 2) and one male (ML) 11-wk-old, intact, captive African lion cubs (Panthera leo leo) were presented with a history of mild vestibular signs. Initial serum vitamin A concentrations were low (140 nmol/L) for ML. Calvarial hyperostosis was confirmed using computed tomography (CT) of the head and cervical vertebrae in each cub. CT measurements were adapted in relation to the skull width. ML showed the most pronounced thickening of the tentorium cerebelli and occipital bone, represented by a tentorium cerebelli to skull width ratio (TCR) of 0.08 (FL 1: 0.06, FL 2: 0.05) and a basisphenoid to skull width ratio (BBR) of 0.07 (FL 1: 0.06, FL 2: 0.04). Magnetic resonance imaging (MRI) revealed cerebellar herniation and cervical intramedullary T2-weighted hyperintensity from C1, extending caudally for at least two cervical vertebrae in all cubs. Treatment was initiated with subcutaneous vitamin A supplementation and feeding of whole carcasses. Improvement in ataxia was noticed 3 wk later. Follow-up CT and MRI examinations were performed in ML after 3 and 8 mon. The affected bones appeared slightly less thickened and TCR and BBR had decreased to 0.05 after 3 mon. The cerebellum remained mildly herniated, accompanied by amelioration of cervical T2w hyperintensities. After 8 mon, evaluation and diagnostic imaging revealed further improvement regarding the neurologic status and measurements (TCR 0.05, BBR 0.04) despite persistence of a subtle cerebellar herniation. In conclusion, bone remodeling and improvement in clinical signs may be achievable in young lion cubs presented with calvarial hyperostosis and may be attributable to high-dose vitamin A supplementation.

A 9-month-old Cavalier King Charles Spaniel with 3-month history of paroxysmal episodes of cervical pain and scratching had a magnetic resonance imaging revealing a large intra-axial cystic lesion in the left frontal lobe, caudal transtentorial and foraminal brain herniation, and cervical syringomyelia. Despite suspected high-grade glioma, clinical signs improved under palliative treatment. Follow-up magnetic resonance imaging 2.5 years later showed a similar lesion size, with no radiological evidence of increased intracranial pressure. The differential diagnosis was reconsidered to possibly porencephaly, congenital cystic malformation or parasitic cyst. The dog remained clinically stable for 19 months before developing acute generalised, single, self-limiting seizures, deteriorating to cluster seizures, stupor, cardiovascular arrest and death. Postmortem magnetic resonance imaging revealed lesion progression with ventricle invasion. Neuropathology confirmed a high-grade oligodendroglioma with subarachnoid and intraventricular drop metastasis. This is the first report describing long-term clinical course and magnetic resonance imaging lesion progression under palliative treatment of a dog ultimately diagnosed with high-grade oligodendroglioma.

OBJECTIVE:To investigate emergency clinicians' comfort level in assessing neurological emergencies and to identify opportunities to foster enhanced training of clinical neurology in the emergency room. DESIGN:Internet-based survey. SETTING:University teaching hospitals and private referral centers. SUBJECTS:One hundred and ninety-two emergency and critical care specialists and resident trainees (ECC) and 104 neurology specialists and resident trainees (NEUR) in clinical practice. INTERVENTIONS:An internet-based survey was distributed via veterinary professional organizations' listserves and message boards and responses were collected between March and April 2020. ECC completed a survey evaluating stress levels associated with neurological emergencies, confidence with neurological examinations, and neuroanatomical localization. NEUR completed a similar survey to report their perception of their ECC colleagues' confidence in the assessment of neurological cases. Chi-square and Mann-Whitney U-tests were used to compare categorical responses and confidence scores between groups. P < 0.002 was considered significant. MEASUREMENTS AND MAIN RESULTS:Fifty-two percent of ECC found neurological emergencies slightly challenging, whereas 85% of NEUR found them moderately to extremely challenging for ECC (P < 0.0001). ECC's median self-reported confidence score in performing a neurologic examination on a scale of 0-100 was 75 (interquartile range [IQR], 27), while NEUR reported a median ECC confidence of 44 (IQR, 25; P < 0.0001). Median self-reported ECC confidence in localizing intracranial, spinal, and neuromuscular disease was 67 (IQR, 40), 88 (IQR, 21), and 60 (IQR, 37), respectively, which was significantly higher than median NEUR-reported ECC confidence of 35 (IQR, 38), 51 (IQR, 31), and 18 (IQR, 20), respectively (all P < 0.0001). Following case transfer, 34% of ECC received NEUR feedback in >75% of cases. CONCLUSIONS:Noticeable discrepancies between ECC and NEUR perceptions of ECC clinical confidence were seen, while no firm evidence of neurophobia could be inferred. Improvements in interdepartmental communication and teaching of clinical neurology may be warranted.

BACKGROUND:Meningoencephalitis of unknown origin (MUO) is an inflammatory disease of the canine central nervous system (CNS) that shares several features with multiple sclerosis (MS) in humans. In approximately 95% of MS patients, ≥ two immunoglobulin G (IgG) oligoclonal bands (OCBs) are detectable exclusively in the cerebrospinal fluid (CSF).HYPOTHESIS/OBJECTIVES:To investigate OCBs in CSF and serum in dogs affected by MUO, intervertebral disc disease (IVDD), idiopathic epilepsy (IE), intracranial neoplasia (IN), steroid-responsive meningitis-arteritis (SRMA), and diseases outside the CNS. We hypothesize that the highest prevalence of CSF-specific OCBs (≥ two OCBs uniquely in the CSF) would be found in dogs affected by MUO.ANIMALS:Client-owned dogs (n = 121) presented to the neurology service due to neurological deficits.METHODS:Prospective study. Measurement of IgG concentration in CSF and serum via a canine IgG ELISA kit. OCB detection via isoelectric focusing (IEF) and immunoblot.RESULTS:Presence of CSF-specific OCBs was significantly higher in dogs with MUO (57%) compared to 22% in IN, 6% in IE, 15% in SRMA, 13% in IVDD, and 0% in the non-CNS group (p < .001). Dogs with MUO were 9.9 times more likely to show CSF-specific OCBs than all other diseases together (95% confidence interval, 3.7-26.4; p < .001).CONCLUSIONS AND CLINICAL IMPORTANCE:MUO showed the highest prevalence of CSF-specific OCBs, indicating an inflammatory B cell response. Future studies are needed to evaluate the prevalence in the specific MUO subtypes and a possible similarity with human MS.

Abstract Background Intervertebral disc disease (IVDD) is a common diagnosis and well-investigated pathological condition in French Bulldogs with neurological deficiencies. However there is currently only one recently published retrospective descriptive study looking for recurrence rates of IVDD in French Bulldogs. Medical reports of French Bulldogs with a first episode of IVDD and surgical treatment were evaluated and reviewed for clinical signs of recurrence. Risk factors for Total-Recurrence, Cervical- and Thoracolumbar-Recurrence were evaluated by means of logistic regression models. The aim of this study was to assess frequency and risk factors associated with the recurrence of IVDD in French Bulldogs. Results One hundred twenty-seven French Bulldogs with a first episode of IVDD and surgical treatment were evaluated. 52.7% (67/127) of these patients showed signs of recurrence. The recurrence rate in the cervical spine was slightly lower (47%) compared to the thoracolumbar spine (56.6%). A significant association with recurrence could be found for the factor age: French Bulldogs with a first episode of IVDD ≤ 3 years seem to be prone for Total-Recurrence (P = 0.002) and Cervical-Recurrence (with ORs ranging from 0.02 to 0.03 for patients older than 3 years). 50% of the recurrences (median) occurred within the first 12 month after the first episode of IVDD. Conclusions Recurrence of IVDD can be expected in more than half of French Bulldogs affected by IVDD. Especially young French Bulldogs are prone for recurrence in cervical spine. Almost every fourth patient with IVDD suffers from a recurrence within 12 months. Future dog owners should be informed about the risk of IVDD and the early onset of recurrences in French Bulldogs.

The feasibility of a newly developed augmentation of ventral fixation technique for surgical stabilization of atlantoaxial instability was clinically evaluated in a cohort of eleven dogs, and long-term clinical outcomes were retrospectively analyzed. The new technique combines wire/suture fixation through a transverse hole in the axis anchored by two screws placed in the alae atlantis or at the cranial end of plates used to bridge the atlantoaxial joint ventrally. A previous biomechanical study demonstrated good stability of this technique during shear loading, comparable to the stability achieved with other standard techniques. Ten dogs improved clinically after surgery and returned to a normal life within 3–6 months of surgery. One dog developed aphonia, dysphagia, and died of aspiration pneumonia three days after surgery. The augmentation of conventional ventral atlantoaxial fixation with the transverse bony corridor of the proximal axis body may be a valuable way to enhance stabilization of the atlantoaxial joint.

The lack of therapeutics that prevent the development of epilepsy, improve disease prognosis or overcome drug resistance represents an unmet clinical need in veterinary as well as in human medicine. Over the past decade, experimental studies and studies in human epilepsy patients have demonstrated that neuroinflammatory pro-cesses are involved in epilepsy development and play a key role in neuronal hyperexcitability that underlies seizure generation. Targeting neuroinflammatory signaling pathways may provide a basis for clinically relevant disease-modification strategies in general, and moreover, could open up new therapeutic avenues for human and veterinary patients with drug-resistant epilepsy. A sound understanding of the neuroinflammatory mechanisms underlying seizure pathogenesis in canine patients is therefore essential for mechanism-based discovery of se-lective epilepsy therapies that may enable the development of new disease-modifying treatments. In particular, subgroups of canine patients in urgent needs, e.g. dogs with drug-resistant epilepsy, might benefit from more intensive research in this area. Moreover, canine epilepsy shares remarkable similarities in etiology, disease manifestation, and disease progression with human epilepsy. Thus, canine epilepsy is discussed as a translational model for the human disease and epileptic dogs could provide a complementary species for the evaluation of antiepileptic and antiseizure drugs. This review reports key preclinical and clinical findings from experimental research and human medicine supporting the role of neuroinflammation in the pathogenesis of epilepsy. Moreover, the article provides an overview of the current state of knowledge regarding neuroinflammatory processes in canine epilepsy emphasizing the urgent need for further research in this specific field. It also highlights possible functional impact, translational potential and future perspectives of targeting specific in-flammatory pathways as disease-modifying and multi-target treatment options for canine epilepsy.

Objectives The aim of this study was to evaluate the association between meningeal enhancement (MgE) and cerebrospinal fluid (CSF) analysis results, their individual association with bacteriology results from affected ear samples and whether these test results influenced clinicians' therapeutic choice in cats with otitis media and interna (OMI). Methods This was a multicentre retrospective study carried out over an 8-year period. Cats diagnosed with OMI, with or without a nasopharyngeal polyp, leading to peripheral vestibular signs were included. Only cats for which MRI with postcontrast T1-weighted sequences and CSF analyses available were included. Cats with intra-axial MRI lesions or empyema were excluded. Results Fifty-eight cats met the inclusion criteria. MgE was reported in 26/58 cases, of which nine had an abnormal CSF result (increased total nucleated cell count [TNCC] or total protein); 32/58 cases had no MgE, of which 10 showed abnormal CSF results. There was no association between bacteriology results (external ear canal or bulla) and MgE or abnormal CSF results. CSF abnormalities were statistically significantly more common in acute cases (n = 16/37) than in chronic cases (n = 3/21; Fischer's test P = 0.04). Prednisolone was prescribed in 10/16 cases with increased TNCC. Among the 42 cases with normal TNCC, 15 received prednisolone and 13 received non-steroidal anti-inflammatory drugs. Various antimicrobial drugs were prescribed in 53/58 cats. Duration of antimicrobial treatment was similar, regardless of positive bacterial culture (5.58 vs 4.22 weeks), abnormal CSF (5.83 vs 4.76 weeks) or MgE (5.33 vs 4.90 weeks). Conclusions and relevance No association was found between the CSF and MgE results. Furthermore, no association was found between MgE, CSF or bacteriology findings. In addition, abnormal CSF results might lead the clinician to treat with corticosteroids, but they did not have any impact on duration of antimicrobial treatment. CSF abnormalities were seen significantly less frequently in chronic cases. The outcome tended to be poorer when MgE was detected on MRI.

Hintergrund Die idiopathische Epilepsie ist die häufigste Form der Epilepsie bei Hunden. Trotz adäquater Behandlung mit Antikonvulsiva wird nur bei circa einem Drittel der Patienten eine Anfallsfreiheit erreicht. Bei einem weiteren Drittel der Patienten wird eine Anfallsreduktion erreicht, während das verbleibende Drittel eine Pharmakoresistenz gegenüber herkömmlichen Antikonvulsiva aufweist. Bei einem Anteil dieser Hunde wird eine immun-mediierte Ätiologie vermutet. Ein Nachweis Liquor-spezifischer oligoklonaler Banden (OKBs) vom Typ Immunoglobulin G (IgG) als Zeichen einer intrathekalen IgG-Synthese würde diesen Verdacht erhärten und könnte das fehlende Ansprechen auf Antikonvulsiva erklären. Ziel dieser Studie ist die Untersuchung des Auftretens Liquor-spezifischer OKBs bei der idiopathischen Epilepsie im Zusammenhang mit dem Ansprechen auf die antikonvulsive Therapie. Die Hypothese lautet, dass bei Hunden mit idiopathischer Epilepsie ein hoher Anteil der Hunde zwei oder mehr Liquor-spezifische OKBs aufweisen und eine negative Korrelation mit der Anfallskontrolle besteht.

Isoelectric focusing followed by immunoblotting is a method routinely used in human medicine to assess the presence of oligoclonal bands (OCBs) in cerebrospinal fluid (CSF) and serum. The detection of OCBs is a valuable diagnostic test, especially important in patients with the suspicion of multiple sclerosis (MS), in which at least two OCBs are found in the CSF not present in paired serum samples in up to 95% of patients. So far, presence of OCBs in CSF and serum of dogs has only been investigated in a small cohort of dogs diagnosed with degenerative myelopathy and healthy dogs. The main objective of the current study was to describe the method used for OCB detection and compare two different canine anti-IgG antibodies: a canine rabbit-anti-IgG antibody (Jackson ImmunoResearch) vs. a canine goat-anti-IgG antibody (Bio-Rad). The method was performed according to the instructions of the commercial kit used. The canine goat-anti-IgG antibody showed a better performance than the canine rabbit-anti-IgG antibody. The availability of the technique of OCB detection in the dog paves the way for further studies, especially in the field of inflammatory diseases of the canine central nervous system, and comparison between specific human and canine diseases.

Epilepsy is a common neurologic disease frequently encountered by small animal practitioners. The disease comprises a multiplicity of clinical presentations and etiologies and often necessitates a comprehensive as well as cost-intensive diagnostic workup. This is mandatory in order to be able to diagnose or exclude a metabolic cause of the seizures and to distinguish between idiopathic and structural epilepsy. The examination by means of magnetic resonance imaging (MRI) represents a central component of the diagnostic workup, which in turn has essential effects on treatment and prognosis. In order to achieve standardized examination and comparable results, it is of utmost importance to use defined MRI protocols. Accordingly, communication and interaction between clinical institutions may be facilitated and as of yet undetected structural changes might be recorded in future MRI techniques. This review article sets particularly emphasis on the definition and classification of epilepsy as well as its diagnostic imaging procedures and refers to statistics and specialists' recommendations for the diagnostic workup in dogs.

Abstract Background The diagnosis of idiopathic epilepsy (IE) in dogs is based on exclusion of other potential causes of seizures. Recently, a novel magnetic resonance imaging (MRI) sequence that utilizes a variant of the rotary saturation approach has been suggested to detect weak transient magnetic field oscillations generated by neuronal currents in humans with epilepsy. Hypothesis/Objectives Effects on the magnetic field evoked by intrinsic epileptic activity can be detected by MRI in the canine brain. As proof‐of‐concept, the novel MRI sequence to detect neuronal currents was applied in dogs. Animals Twelve dogs with IE and 5 control dogs without a history of epileptic seizures were examined. Methods Prospective case‐control study as proof‐of‐concept. All dogs underwent a clinical neurological examination, scalp electroencephalography, cerebrospinal fluid analysis, and MRI. The MRI examination included a spin‐locking (SL) experiment applying a low‐power on‐resonance radiofrequency pulse in a predefined frequency domain in the range of oscillations generated by the epileptogenic tissue. Results In 11 of 12 dogs with IE, rotary saturation effects were detected by the MRI sequence. Four of 5 control dogs did not show rotary saturation effects. One control dog with a diagnosis of neuronal ceroid lipofuscinosis had SL‐related effects, but did not have epileptic seizures clinically. Conclusions and Clinical Importance The proposed MRI method detected neuronal currents in dogs with epileptic seizures and represents a potential new line of research to investigate neuronal currents possibly related to IE in dogs.

ZusammenfassungEpilepsie ist eine neurologische Erkrankung, die dem Kleintierpraktiker im klinischen Alltag häufig begegnet. Die Erkrankung umfasst eine Vielzahl klinischer Ausprägungen und Ätiologien und die klinische Aufarbeitung bedarf in vielen Fällen einer kostenaufwendigen und umfangreichen Diagnostik. Diese ist notwendig, um eine metabolische Ursache für die Krampfanfälle festzustellen oder auszuschließen bzw. zwischen idiopathischer und struktureller Epilepsie unterscheiden zu können. Für die Klassifikation der Epilepsie ist die Untersuchung mittels Magnetresonanztomografie (MRT) ein zentraler Bestandteil der Diagnosefindung, die sich entscheidend auf Therapie und Prognose auswirkt. Die Standardisierung von MRT-Protokollen hat große Bedeutung, um eine einheitliche Untersuchung und vergleichbare Ergebnisse zu erzielen. Dies kann die Kommunikation und Interaktion zwischen klinischen Einrichtungen erleichtern und die Möglichkeit bieten, noch unerkannte strukturelle Veränderungen im MRT zu erfassen. Dieser Übersichtsartikel beschäftigt sich im Zentralen mit der Definition und Klassifikation der Epilepsie sowie der bildgebenden Diagnostik der Epilepsie beim Hund und nimmt Bezug auf Statistiken und Empfehlungen von Spezialisten zur klinischen Fallaufarbeitung.

OBJECTIVE:The aim of this study was to validate an imaging technique for evaluation of spinal surgery accuracy and to establish accuracy and safety of freehand technique in the thoracolumbar spine of large breed dogs.STUDY DESIGN:After thoracolumbar spine computed tomography (CT), 26 drilling corridors were planned then drilled to receive 3.2 mm positive profile pins using a freehand technique. After pin removal, CT was repeated. All entry points, exit points and angles of the preoperative planned trajectories were compared with postoperative ones using an image registration and fusion technique by three observers. Corridor coordinates for entry and exit points were evaluated in three dimensions and angles were measured in one plane. Intraclass correlation coefficient (ICC) was used to establish the imaging technique reliability and descriptive statistics were used to report on the freehand technique accuracy. Safety was evaluated using a vertebral cortical breach grading scheme.RESULTS:Intraclass correlation coefficient for the entry points, exit points and angle were 0.79, 0.96 and 0.92 respectively. Mean deviations for the entry points, exit points and angle were 3.1 mm, 6.3 mm and 7.6 degrees respectively. Maximum deviations were 6.3 mm, 11.0 mm and 16.4 degrees. Most deviations were lateral and caudal. All corridors were judged as safe.CONCLUSION:The imaging technique reliability was good to excellent to study spinal surgery accuracy. Implant deviations should be anticipated when planning stabilization surgery in large breed dogs using the freehand-guided technique.

Case summary A 4-month-old cat was presented with acute paraplegia after the referring veterinarian performed a subcutaneous injection (cefovecin and dexamethasone) in the caudodorsal thoracic area, during which the cat suddenly became uncooperative. A complete neurological examination performed 1 day after the injection revealed paraplegia without deep pain perception and reduced segmental spinal reflexes in the pelvic limbs. Findings were consistent with either an L4–S3 myelopathy or a T3–L3 myelopathy with subsequent spinal shock. MRI showed swelling of the spinal cord from T1 to L1 with heterogeneous T2-weighted intramedullary hyperintensity and no contrast enhancement. A centrally located intraspinal signal void was visible in T2*-weighted images. These changes were compatible with a suspected traumatic intraspinal injection. Despite intensive supportive care over 4 days, neurological status did not improve and the cat was euthanased. Gross pathology findings revealed severe intramedullary haemorrhage and myelomalacia in the T10–L1 spinal cord segments. Histopathology of the spinal cord after haematoxylin and eosin staining revealed a severe intramedullary space-occupying haemorrhage with focal malacia. A trajectory-like, optically empty cavity containing some eosinophilic droplets at the edges was detected. Although no further evidence of trauma was noted in the surrounding structures, the spinal cord changes were compatible with a perforating trauma. Relevance and novel information To our knowledge, this is the first report of thoracic intraspinal injection causing myelomalacia defined by an ante-mortem MRI and confirmed post mortem by histopathology. The traumatic myelopathy appeared to be most compatible with an intraspinal injection causing vascular rupture.