Associations between neutering and idiopathic epilepsy in Labrador retrievers and Border collies under primary veterinary care in the UK.

There are sparse published scientific data on associations between neutering and the severity and survival of dogs with idiopathic epilepsy. This study aimed to explore the timing of neutering with respect to onset of seizures in dogs with idiopathic epilepsy. Associations between neutering and both age of onset of seizures and the occurrence of cluster seizures or status epilepticus were examined. Survival analysis investigated the effects of sex-neuter categories. The median survival time of Border collies was compared with data previously reported in literature. The study included veterinary primary-care clinical data on 117 Labrador retrievers and 57 Border collies diagnosed with idiopathic epilepsy from the VetCompass project in the UK. The majority (74.2%; P≤0.001) of neutered cases were neutered before the onset of seizures. Age (years) at onset of seizures did not differ between dogs intact at time of onset and dogs neutered before onset of seizures (males 3.6 vs. 3.7; P=0.468 and females 3.4 vs. 4.1; P=0.154). Neuter status was not associated with the occurrence of cluster seizures (males P=0.947 and females P=0.844). Dogs intact at onset of seizures had longer median survival times than dogs neutered before onset of seizures (males, 1436 days vs. 1234 days; P=0.019; females, 1778.5 days vs. 1261 days; P=0.027). Median survival time of 1393 days for Border collies was longer than previously reported (P≤0.001). These results do not support recommendations to neuter dogs with idiopathic epilepsy within an evidence-based treatment plan.

Cortical motor threshold determination in dogs.

In humans, determining the cortical motor threshold (CMT) is a critical step in successfully applying a transcranial magnetic stimulation (TMS) treatment. Stimulus intensity, safety and efficacy of a TMS treatment are dependent of the correct assessment of the CMT. Given that TMS in dogs could serve as a natural animal model, an accurate and reliable technique for the measurement of the CMT should be available for dogs. Using a visual descending staircase paradigm (Rossini paradigm), the CMT repeatability was assessed and compared to the electromyographic (EMG) variant. The influence of a HF-rTMS treatment on the CMT was examined. Subsequently, the CMT was measured under sedation and general anaesthesia. Finally, the coil-cortex distance was associated with the CMT, weight, age and gender. During one year the CMT was measured three times, during which it remained constant, although a higher CMT was measured (40% higher machine output) when using EMG (P-value < .001) and under general anaesthesia (P-value = .005). On average, a 40% and 12% higher machine output were registered. An aHF-rTMS protocol does not influence the CMT. Males have on average a 5.2 mm larger coil cortex distance and an 11.81% higher CMT. The CMT was positively linearly associated (P-value < .05) with the weight and age of the animals. Only within female subjects, a positive linear association was found between the CMT and the coil-cortex distance (P-value = .02). Using the visual Rossini paradigm, the CMT can be reliably used over time and during a TMS treatment. It has to be kept in mind that when using EMG or assessing the CMT under general anaesthesia, a higher CMT is to be expected. As in humans, every parameter that influences the coil-cortex distance may also influence the CMT.

Clinical presentation, diagnostic findings, prognostic factors, treatment and outcome in dogs with meningoencephalomyelitis of unknown origin: A review.

Meningoencephalomyelitis of unknown origin (MUO) encompasses a group of idiopathic, most likely immune mediated, inflammatory central nervous system diseases that cause clinical, diagnostic and treatment challenges to veterinary neurologists. Clinical criteria for obtaining this presumptive diagnosis are currently available, and multiple treatment protocols have previously been investigated in small (prospective or retrospective) case series. As this group of diseases is considered fatal if left untreated, the identification of clinically usable prognostic indices could be of great value. This review provides an overview of recent developments in the clinical presentation, diagnostic findings, possible prognostic factors, treatment and outcome in dogs diagnosed with MUO.

Imepitoin withdrawal in dogs with idiopathic epilepsy well-controlled with imepitoin and phenobarbital and/or potassium bromide does not increase seizure frequency.

Phenobarbital or potassium bromide (KBr) add-on treatment decreases the average monthly seizure frequency in dogs with idiopathic epilepsy resistant to a maximum dose of imepitoin. The importance of continued administration of imepitoin in these dogs is currently unknown. The goal of this study was to assess whether imepitoin withdrawal would destabilize epileptic seizure control. In this prospective clinical trial epileptic seizure control was evaluated by comparing the monthly seizure frequency of 13 dogs with well-controlled idiopathic epilepsy receiving a combination of imepitoin and phenobarbital (n=4), imepitoin and KBr (n=7), and imepitoin, phenobarbital and KBr (n=2) during a period of 3-6 months (pre-withdrawal period), with a follow-up period of 9-12 months after withdrawal of imepitoin (post-withdrawal period). Adverse effects were also recorded before and after withdrawal of imepitoin. Imepitoin was tapered off over 3 months as follows: 20mg/kg twice daily for 1 month, then 10mg/kg twice daily for 1 month, then once daily for 1 month. Withdrawal of imepitoin did not increase monthly seizure frequency (P=0.9). Moreover, all owners reported improvement in the adverse effects experienced by their dog after withdrawal of imepitoin. Imepitoin withdrawal in epileptic dogs that were well-controlled with imepitoin and phenobarbital and/or KBr did not worsen epileptic seizure control, and possibly decreased antiepileptic treatment-related adverse effects. However, a worsening of seizure frequency could occur in individual cases.

Intranasal Midazolam versus Rectal Diazepam for the Management of Canine Status Epilepticus: A Multicenter Randomized Parallel-Group Clinical Trial.

BACKGROUND: Intranasal administration of benzodiazepines has shown superiority over rectal administration for terminating emergency epileptic seizures in human trials. No such clinical trials have been performed in dogs. OBJECTIVE: To evaluate the clinical efficacy of intranasal midazolam (IN-MDZ), via a mucosal atomization device, as a first-line management option for canine status epilepticus and compare it to rectal administration of diazepam (R-DZP) for controlling status epilepticus before intravenous access is available. ANIMALS: Client-owned dogs with idiopathic or structural epilepsy manifesting status epilepticus within a hospital environment were used. Dogs were randomly allocated to treatment with IN-MDZ (n = 20) or R-DZP (n = 15). METHODS: Randomized parallel-group clinical trial. Seizure cessation time and adverse effects were recorded. For each dog, treatment was considered successful if the seizure ceased within 5 minutes and did not recur within 10 minutes after administration. The 95% confidence interval was used to detect the true population of dogs that were successfully treated. The Fisher's 2-tailed exact test was used to compare the 2 groups, and the results were considered statistically significant if P < .05. RESULTS: IN-MDZ and R-DZP terminated status epilepticus in 70% (14/20) and 20% (3/15) of cases, respectively (P = .0059). All dogs showed sedation and ataxia. CONCLUSIONS AND CLINICAL IMPORTANCE: IN-MDZ is a quick, safe and effective first-line medication for controlling status epilepticus in dogs and appears superior to R-DZP. IN-MDZ might be a valuable treatment option when intravenous access is not available and for treatment of status epilepticus in dogs at home.

Spinal Arachnoid Diverticula: Outcome in 96 Medically or Surgically Treated Dogs.

BACKGROUND: Little is reported about the role of medical management in the treatment of spinal arachnoid diverticula (SAD) in dogs. OBJECTIVES: To describe the outcome of 96 dogs treated medically or surgically for SAD. ANIMALS: Ninety-six dogs with SAD. METHODS: Retrospective case series. Medical records were searched for spinal arachnoid diverticula and all dogs with information on treatment were included. Outcome was assessed with a standardized questionnaire. RESULTS: Fifty dogs were managed medically and 46 dogs were treated surgically. Dogs that underwent surgery were significantly younger than dogs that received medical management. No other variables, related to clinical presentation, were significantly different between both groups of dogs. The median follow-up time was 16 months (1-90 months) in the medically treated and 23 months (1-94 months) in the surgically treated group. Of the 38 dogs treated surgically with available long-term follow-up, 82% (n = 31) improved, 3% (n = 1) remained stable and 16% (n = 6) deteriorated after surgery. Of the 37 dogs treated medically with available long-term follow-up, 30% (n = 11) improved, 30% (n = 11) remained stable, and 40% (n = 15) deteriorated. Surgical treatment was more often associated with clinical improvement compared to medical management (P = .0002). CONCLUSIONS AND CLINICAL IMPORTANCE: The results of this study suggest that surgical treatment might be superior to medical treatment in the management of SAD in dogs. Further studies with standardized patient care are warranted.

Clinical presentation, diagnostic findings and outcome in dogs diagnosed withpresumptive spinal-only meningoen-cephalomyelitis of unknown origin.

OBJECTIVES: To summarise clinical presentation, diagnostic findings and long-term outcome for dogs clinically diagnosed with meningoencephalomyelitis of unknown origin affecting the spinal cord alone. METHODS: Medical records were reviewed for dogs diagnosed with presumptive spinal-only meningoencephalomyelitis of unknown origin between 2006 and 2015. RESULTS: 21 dogs were included; the majority presented with an acute (43%) or chronic (52%) onset of neurological signs. Ambulatory paresis was the most common neurological presentation (67%). Neurological examination most commonly revealed a T3-L3 myelopathy, and spinal hyperaesthesia was a common finding (71%). A spinal cord lesion was visible in 90% of cases on magnetic resonance imaging. Eighteen lesions (86%) showed parenchymal contrast enhancement and 17 lesions (81%) showed contrast enhancement of overlying meninges. All dogs were treated with immunosuppressive doses of glucocorticosteroids, sometimes combined with cytosine arabinoside. At time of data capture, 10/21 dogs (48%) had died or been euthanased because of the condition. Overall median survival time was 669 days. CLINICAL SIGNIFICANCE: Meningoencephalomyelitis of unknown origin should be considered in the differential diagnosis of dogs presenting with a progressive myelopathy. Magnetic resonance imaging features can possibly help to distinguish presumptive meningoencephalomyelitis of unknown origin from other more common spinal diseases. Overall, long-term survival is guarded, approximately 50% of dogs will die or be euthanased despite appropriate therapy.

Phenobarbital or potassium bromide as an add-on antiepileptic drug for the management of canine idiopathic epilepsy refractory to imepitoin.

Imepitoin has recently been approved in Europe for the management of dogs with idiopathic epilepsy. Currently, there is no evidence-based information available on the efficacy of antiepileptic drugs used as additions to the therapeutic regimen in dogs with idiopathic epilepsy that are not well controlled with imepitoin. The goal of this study was to evaluate the efficacy of phenobarbital or potassium bromide (KBr) as add-on antiepileptic drugs for controlling dogs refractory to a maximum dose of imepitoin (30 mg/kg twice daily). The study was performed as a prospective, randomised, controlled clinical trial. The efficacy of phenobarbital and KBr was evaluated by comparing monthly seizure frequency (MSF), monthly seizure day frequency (MSDF), the presence of cluster seizures during a retrospective 2-month period with a prospective follow-up of 6 months, and the overall responder rate. Twenty-seven dogs were included in the study, 14 dogs in the phenobarbital group and 13 dogs in the KBr group. Both median MSF and MSDF decreased in the phenobarbital group (both P = 0.001) and in the KBr group (P = 0.004 and P = 0.003, respectively). Overall, the number of dogs with cluster seizures decreased (P = 0.0005). The responder rate was 79% vs. 69% in the phenobarbital and KBr groups, respectively. We conclude that phenobarbital or KBr add-on treatment decreases median MSF and MSDF in epileptic dogs refractory to a maximum dose of imepitoin. Combination therapy was generally well tolerated and resulted in an improvement in seizure management in the majority of the dogs.

Motor evoked potentials in standing and recumbent calves induced by magnetic stimulation at the foramen magnum.

The aims of this study were to determine reference values for magnetic motor evoked potentials (mMEPs) in calves and the influence of position during examination (standing or lateral recumbency). Reference values were determined using 41 healthy Holstein Friesian bull calves aged 1-10 months; standing and lateral recumbency were examined in 11 calves. Maximal magnetic stimulation was performed at the level of the foramen magnum with a magnetic field of 4 T at the coil surface. In standing position, distinct, reproducible mMEPs were obtained in all calves. Onset latency (LAT) (mean ± standard deviation) was significantly shorter in the thoracic limbs (34.4 ± 3.1 ms) than in the pelvic limbs (44.6 ± 3.0 ms). Amplitude (AMPL) was significantly higher in the thoracic limbs (3.7 ± 1.7 mV) than in the pelvic limbs (3.3 ± 1.7 mV) and significantly increased with body length. Age, body weight, height at the withers and rectal temperature had no significant association with LAT or AMPL, and no differences between left and right were noted. In the lateral position, only 64% of the calves showed responses in the four limbs; in these calves, LAT (29.7 ± 4.7 ms) and AMPL (3.0 ± 1.8 mV) in the thoracic limbs were significantly different from AMPL (47.0 ± 7.4 ms) and LAT (2.1 ± 2.1 mV) in the pelvic limbs. In conclusion, mMEPs in limb muscles can be evoked in calves by stimulation at the level of the foramen magnum. mMEPs are more difficult to obtain in lateral recumbency than in standing calves.

Detection of compressive hydrated nucleus pulposus extrusion in dogs with multislice computed tomography.

Compressive hydrated nucleus pulposus extrusion (HNPE) in dogs is defined as acute extradural compression by hydrated nucleus pulposus material at the level of the associated intervertebral disc. Magnetic resonance imaging (MRI) is the imaging modality of choice for diagnosis of HNPE. The aims of this study were to determine the usefulness of unenhanced computed tomography (CT) and contrast enhanced CT (CE-CT), and the sensitivity and specificity of CE-CT, for detection of compressive HNPE. Using CE-CT, HNPE was visualised as a hypodense extradural compressive lesion with rim enhancement immediately dorsal to the intervertebral disc space, with a sensitivity of 91% and a specificity of 100%. CE-CT is a useful technique to detect compressive HNPE in dogs. However, if no clear lesion is identified with CE-CT, or if additional information about intramedullary changes is required, MRI still needs to be performed.

Prognostic factors for 1-week survival in dogs diagnosed with meningoencephalitis of unknown aetiology.

Although long-term outcomes of meningoencephalitis of unknown aetiology (MUA) in dogs have been evaluated, little is known about short-term survival and initial response to therapy. The aim of this study was to evaluate possible prognostic factors for 7-day survival after diagnosis of MUA in dogs. Medical records were reviewed for dogs diagnosed with MUA between 2006 and 2015. Previously described inclusion criteria were used, as well as 7-day survival data for all dogs. A poor outcome was defined as death within 1 week. Of 116 dogs that met inclusion criteria, 30 (26%) died within 7 days of diagnosis. Assessed variables included age, sex, bodyweight, duration of clinical signs and treatment prior to diagnosis, venous blood glucose and lactate levels, white blood cell count on complete blood count, total nucleated cell count/total protein concentration/white blood cell differentiation on cerebrospinal fluid (CSF) analysis, presence of seizures and cluster seizures, mentation at presentation, neuroanatomical localisation, imaging findings and treatment after diagnosis. Multivariate analysis identified three variables significantly associated with poor outcome; decreased mentation at presentation, presence of seizures, and increased percentage of neutrophils on CSF analysis. Despite initiation of appropriate treatment, more than a quarter of dogs died within 1 week of diagnosis of MUA, emphasising the need for evaluation of short-term prognostic factors. Information from this study could aid clinical staff to provide owners of affected dogs with prognostic information.

No evidence that medicinal honey reduces bacterial skin colonisation at a peripheral catheter insertion site in dogs.

OBJECTIVES: To determine whether topical exit-site application of medicinal honey at the catheter insertion place reduces bacterial skin colonisation. MEASUREMENTS AND RESULTS: Dogs were selected at random and divided into the honey or the control group. When the catheter was removed, an area of approximately 3×3 cm of the skin at the insertion site was sampled with a sterile cotton swab. The catheter stayed in place for a median of 84 hours. Out of 46 patients, 6 patients in the honey group and 5 out of 54 patients in the control group had a positive skin culture at the time of catheter removal (P=0·547). Infection was clinically suspected in 1 of those 11 dogs; catheter-associated complications were observed in 8 additional dogs that did not have a positive skin culture. CLINICAL SIGNIFICANCE: Few catheter-associated complications were observed. Extra attention to hygiene by working with a standardised catheter placement and handling protocol might have resulted in this low incidence. In this study topical application of a medicinal honey did not reduce bacterial skin colonisation at the insertion site of peripheral catheters in dogs.

The effect of imepitoin, a recently developed antiepileptic drug, on thyroid parameters and fat metabolism in healthy Beagle dogs.

Since early 2013, imepitoin has been used in most European countries for the management of recurrent single generalised epileptic seizures in dogs with idiopathic epilepsy. It has been reported that imepitoin is as effective as phenobarbital (PB) in controlling seizures in dogs with newly diagnosed idiopathic epilepsy and it has a clinically superior safety profile. As the use of imepitoin gains popularity, its effect on serum thyroid parameters warrants further investigation since long-term PB administration influences thyroid parameters in dogs, which could lead to misinterpretation of laboratory results and incorrect diagnosis of thyroidal illness. A prospective study was conducted to compare the effect of orally administered PB and imepitoin on serum concentrations of total thyroxine (TT4), triiodothyronine, free thyroxine, thyroglobulin autoantibodies, thyroid-stimulating hormone, cholesterol and triglycerides in healthy Beagle dogs. These parameters were determined prior to and at 6, 12 and 18 weeks after antiepileptic drug administration. The starting dose of PB (5 mg/kg PO twice daily; range, 4.4-6.0 mg/kg) was monitored and adjusted to obtain optimal therapeutic serum concentrations (30-35 g/mL). Imepitoin was administered at 30 mg/kg PO twice daily (range, 29.2-35.7 mg/kg). Imepitoin administration did not affect any of the thyroid parameters over an 18-week period. In contrast, serum TT4 concentrations decreased significantly over time in dogs receiving PB (P <0.05). Serum cholesterol concentrations increased significantly over time in dogs in the imepitoin group, but not to the same extent as commonly seen in dogs with primary hypothyroidism.

Diffuse idiopathic skeletal hyperostosis of the spine in a nine-year-old cat.

A nine-year-old intact female domestic shorthair cat was evaluated for paraparesis, ataxia and severe spinal hyperaesthesia. Neurological examination indicated a T3-L3 spinal cord segment lesion. Computed tomography of the thoracolumbar and lumbosacral vertebral column was performed. This showed contiguous smooth new bone formation ventral and lateral to the vertebrae extending from the cranial thoracic area to the lumbosacral junction and appearing similar to canine diffuse idiopathic skeletal hyperostosis. There was also marked dorsolateral stenosis of the vertebral canal at the level of T4-T5 because of degenerative changes of the facet joints. To the authors' knowledge, this is the first published report of feline diffuse idiopathic skeletal hyperostosis.

Recording of cord dorsum potentials in calves.

Cord dorsum potentials are sensory evoked potentials being used to assess proximal sensory nerve, dorsal nerve root and spinal cord dorsal horn function. The purpose of the present study was to establish normal values for onset latency, peak latency and peak-to-peak amplitude of cord dorsum potentials after saphenous nerve stimulation in 15 healthy calves. Under general anesthesia, the saphenous nerve was stimulated in the periphery and cord dorsum potentials were recorded from the interarcuate space L3-L4, L4-L5, L5-L6 and L6-S1. Cord dorsum potentials were easily recorded at the different recording sites and consisted of a large negative peak followed by a long latency positive phase. The largest responses were recorded at the L5-L6 interarcuate space. Body temperature significantly influenced peak-to-peak amplitude. Onset latency prolonged with increasing limb length.

Low-field MRI and multislice CT for the detection of cerebellar (foramen magnum) herniation in Cavalier King Charles Spaniels.

BACKGROUND: Cavalier King Charles Spaniels (CKCS) have a high prevalence of Chiari-like malformation (CM). Herniation of the cerebellum into the foramen magnum is a key diagnostic feature for CM. Midsagittal MR images are the preferred technique for visualizing cerebellar herniation (CH). OBJECTIVE: To investigate whether CT can be used to diagnose CH. ANIMALS: Fifteen client-owned CKCS dogs referred for investigation of the brain and cranial cervical spine on MRI and CT. METHODS: Two reviewers retrospectively analyzed midsagittal T1WSE and T2WSE MR images and midsagittal pre- and postcontrast 2D multiplanar reformatted CT images from each dog for the presence of CH. And, if present, the length (mm, CHL) of the herniation was measured. The results were analyzed statistically. RESULTS: There was no significant difference between the different observers and techniques for the detection of CH and measurement of CHL. Overall, the CHL was longer on the CT images. CONCLUSION AND CLINICAL IMPORTANCE: Both techniques are useful for detecting CH and measuring CHL. Because CHL does not have a known direct impact on the clinical presentation of CM, CT can be used as a diagnostic tool in a routine clinical practice for CM in CKCS when MRI is not available. We emphasize that MRI is the standard screening technique in CKCS for breeding purposes to detect the presence of CM and SM and, at the current time, CT cannot replace MRI.

Association between estrus and onset of seizures in dogs with idiopathic epilepsy.

BACKGROUND: Catamenial epilepsy in humans is defined as changes in seizure frequency over the course of the menstrual cycle. Three hormonally based patterns of seizure exacerbation have been determined. OBJECTIVES: The aim of this study was to evaluate whether there is an association between onset of seizures and the estrous cycle in intact bitches with presumptive idiopathic epilepsy and whether a pattern to the onset of seizures could be recognized. ANIMALS: Forty-five intact female dogs from a hospital population with a presumptive diagnosis of idiopathic epilepsy. METHODS: In a retrospective study, the database of a small animal hospital in Sweden was searched for medical records of intact female dogs diagnosed with epilepsy or seizures. The stage of the estrous cycle as reported either by the owner or the veterinarian at the time of the first seizure was noted. RESULTS: Of the 45 dogs with idiopathic epilepsy, 17 (38%) had their first seizure when in heat and six dogs (13%) had their first seizure 1-3 months after heat. Nine dogs (20%) had seizures reoccurring in relation to their estrous cycle. CONCLUSIONS AND CLINICAL IMPORTANCE: These findings suggest an association between estrus and onset of seizures in intact bitches with presumptive idiopathic epilepsy. Two hormonally based patterns could be recognized: one during heat and one during a specific time point at the end of diestrus. This could be explained by the proconvulsive effects of estrogen or loss of protective effect against seizures of progesterone, respectively.

Unilateral shunt formation with thoracic aortic dissection in a whippet.

A three-year-old neutered male whippet was presented with intermittent, exercise-induced paraparesis. Femoral pulses were bilaterally absent. Neurologic examination was suggestive of a thoracolumbar myelopathy. Blood pressure measurements revealed hypotension in both pelvic limbs, hypertension in the right thoracic limb and it was immeasurable in the left thoracic limb. Echocardiography was within reference limits. A clear vascular pulsation was palpable on the right ventral abdominal wall. Computed tomographic angiography revealed a dissection of the aortic wall between the left subclavian artery and the brachiocephalic trunk with subsequent thrombus formation. A shunt between the right internal thoracic, cranial and caudal epigastric arteries to preserve blood flow to the pelvic limbs was visualized. Necropsy was declined by the owner. This is the first case report describing the formation of a unilateral vascular shunt following a thoracic aortic occlusion, which presented as exercise-induced paraparesis.

Signalment, clinical presentation, and diagnostic findings in 122 dogs with spinal arachnoid diverticula.

BACKGROUND: Most information about spinal arachnoid diverticula (SADs) in dogs has been retrieved from relatively small case series. The aim of this study was to describe this disease in a larger number of dogs. OBJECTIVES: Description of the signalment, clinical presentation, and imaging findings of a large number of dogs with SADs. ANIMALS: One hundred and twenty-two dogs with SADs. METHODS: Retrospective case series study. All medical records were searched for a diagnosis of SAD. The diagnosis was made based on myelography, computed tomography myelography (CT-m), or magnetic resonance imaging (MRI). RESULTS: In the 122 dogs, 125 SADs were identified. Sixty-five were located in the cervical region and 60 in the thoracolumbar region. A higher body weight was significantly associated with a cervical localization of the SAD (P < .001). Ninety-five dogs were male and 27 dogs were female. Male dogs were significantly overrepresented (P < .0001). The most commonly affected breed was the Pug dog. Previous or concurrent spinal disorders, in the near proximity of the diagnosed SAD, were seen in 26 dogs. Eight of 13 French Bulldogs and 7 of 21 Pug dogs with SADs had a previous or concurrent spinal disease, whereas other spinal disorders occurred in only 1 of 17 Rottweilers with SADs. CONCLUSIONS AND CLINICAL IMPORTANCE: Pug dogs and French Bulldogs might have a predisposition for SAD development. In a large percentage of these dogs, a concurrent spinal disorder, which might predispose to SAD formation, was diagnosed. The high prevalence in male dogs warrants further investigation.

Comparison between symptomatic treatment and lomustine supplementation in 71 dogs with intracranial, space-occupying lesions.

Brain neoplasia is diagnosed in an increasing number of dogs. Consequently, there is a higher need for an effective treatment. Chemotherapy is considered in cases where surgery or radiation is not optional. The objective of this retrospective study was to evaluate the difference in median survival time (MST) of dogs with intracranial masses, treated symptomatically with corticosteroids and anti-epileptic drugs, compared with the same symptomatic treatment supplemented with lomustine. The records of 71 dogs with intracranial masses were retrospectively evaluated. Fifteen dogs were treated symptomatically with corticosteroids and anti-epileptics, and 56 dogs received additional therapy with lomustine. There was no statistically significant difference in MST between both groups, being 60 and 93 days, respectively. Age, duration of symptoms, intracranial localization of the mass and intra- or extra-axial localization had no influence on survival time. However, female dogs survived significantly longer than male dogs.