Transcerebellar ventriculoperitoneal shunt for management of presumed arachnoid diverticulum in the fourth ventricle of a dog.

OBJECTIVE: To describe the approach for placement of a transcerebellar fourth ventriculoperitoneal shunt for management of presumed fourth ventricle arachnoid diverticulum and secondary obstructive hydrocephalus of a dog. To describe the outcome of this procedure. STUDY DESIGN: Case report. ANIMALS: Male entire English springer spaniel, 3 years 9 months of age. METHODS: The dog was initially presented for management of acute, progressive, and multifocal brainstem and forebrain dysfunction. Magnetic resonance imaging revealed internal obstructive hypertensive hydrocephalus. The dog was managed via ventriculoperitoneal shunting from the left lateral ventricle and made an excellent recovery. The dog acutely deteriorated 18 months after initial discharge and follow-up magnetic resonance imaging confirmed the ventricular shunt remained in situ with normal-sized lateral ventricles but revealed a cystlike lesion within the fourth ventricle, presumed to be a fourth ventricle arachnoid diverticulum. The diverticulum was causing mass effect and resultant compression of adjacent neuroparenchyma. A second ventriculoperitoneal shunt was subsequently placed into the fourth ventricle via the caudal cranial fossa and cerebellum. This was attached to a three-way connector, to which the existing shunt (within the left lateral ventricle) was also attached, and then secured to the existing medium-pressure valve. RESULTS: Postoperatively, the dog immediately developed mild vestibular-cerebellar ataxia, with a marked improvement after 3 months. There were no shunt-associated complications. Long-term follow up at 40 months after the second surgical procedure revealed a normal neurological examination. CONCLUSION: Transcerebellar ventriculoperitoneal shunt placement for treatment of a presumed fourth ventricle arachnoid diverticulum was performed and was associated with a favorable long-term outcome.

Neurogenic keratoconjunctivitis sicca in 34 dogs: A case series.

OBJECTIVE: To describe the clinical findings, imaging features, underlying conditions, treatment, and progression of dogs presented between 2010 and 2019 with neurogenic keratoconjunctivitis sicca (NKCS). METHODS: Dogs diagnosed with NKCS were searched in the clinical database. Inclusion criteria were STT-1 readings <15 mm/min, clinical signs of KCS with concurrent ipsilateral xeromycteria. RESULTS: Thirty-four cases were identified. Mean age at presentation was 8.2 years, median 8.9 years (0.3-14.7). Twenty dogs were male, and 14 dogs were female. Concurrent neurological deficits included facial neuropathy (n = 13, 38%), peripheral vestibular syndrome (n = 10, 29%), and Horner's syndrome (n = 5, 15%). Advanced imaging was acquired in 53% of cases (n = 18). Etiologies included idiopathic (n = 18, 53%), endocrinopathy (n = 6, 18%), otitis interna (n = 4, 12%), head trauma (n = 3, 9%), iatrogenic (post-TECA-LBO, n = 1, 3%), brainstem mass (n = 1, 3%), and an area of inflammation in the pterygopalatine fossa (n = 1, 3%). Treatment for NKCS was initiated in most cases (n = 30, 88%) including: oral pilocarpine 2% and lacrimostimulant (n = 19), oral pilocarpine 2% only (n = 3), or lacrimostimulant only (n = 8). A mean time follow-up of 3.7 months, median 3 months (1-14) was available in 23 cases (68%). Eleven cases with follow-up were responsive (48%) with resolution of the clinical signs in a median time 4 months (1-10), and all of them were treated with oral pilocarpine (±lacrimostimulant). CONCLUSIONS: Most cases presented as idiopathic NKCS; in others, an underlying cause of facial neuropathy was identified. All responsive cases were treated with oral pilocarpine 2%.

Magnetic resonance imaging of the caudal portion of the digastric muscle in canine idiopathic facial neuropathy.

Idiopathic is the most common etiology for acute onset of facial neuropathy in dogs with limited number of studies describing MRI characteristics. A retrospective, observational study was performed using archived records, aiming to describe the MRI features of the caudal portion of the digastric muscle in dogs diagnosed with idiopathic facial neuropathy and to determine correlation with prognosis. Client-owned dogs presented to a referral hospital between 2009 and 2019, diagnosed with unilateral idiopathic facial neuropathy and having undergone MRI, with images including the caudal portion of the digastric muscle, were included (n = 19). MRI appearance of the affected muscle, including degree of muscle atrophy, signal intensity, enhancement post-contrast, and enhancement characteristics of the affected facial nerve, was described and compared to the contralateral, clinically unaffected caudal portion of the digastric muscle. Correlation between MRI appearance and outcome at 1-month and 3-months following onset of clinical signs was investigated. The majority of patients demonstrated some degree of muscle atrophy (n = 17, 89%), hyperintensity in T2W (n = 17, 89%), and pre-contrast T1W (n = 15, 79%) images, as well as contrast enhancement of the affected muscle (n = 14, 74%) and affected facial nerve (n = 9, 47%). There was no statistically significant correlation between atrophy or enhancement of the affected caudal portion of the digastric muscle nor between enhancement of the affected facial nerve and outcome. Hyperintensity both in T2W images and pre-contrast T1W images was significantly correlated with a worse prognosis. Ensuring inclusion and evaluation of this muscle in MRI may therefore be indicated in canine idiopathic facial neuropathy.

Early CT in dogs following traumatic brain injury has limited value in predicting short-term prognosis.

Traumatic brain injury is associated with a high risk of mortality in veterinary patients, however publications describing valid prognostic indicators are currently lacking. The objective of this retrospective observational study was to determine whether early CT findings are associated with short-term prognosis following traumatic brain injury (TBI) in dogs. An electronic database was searched for dogs with TBI that underwent CT within 72 h of injury; 40 dogs met the inclusion criteria. CT findings were graded based on a Modified Advanced Imaging System (MAIS) from grade I (normal brain parenchyma) to VI (bilateral lesions affecting the brainstem with or without any foregoing lesions of lesser grades). Other imaging features recorded included presence of midline shift, intracranial hemorrhage, brain herniation, skull fractures, and percentage of total brain parenchyma affected. Outcome measures included survival to discharge and occurrence of immediate onset posttraumatic seizures. Thirty dogs (75%) survived to discharge. Seven dogs (17.5%) suffered posttraumatic seizures. There was no association between survival to discharge and posttraumatic seizures. No imaging features evaluated were associated with the study outcome measures. Therefore, the current study failed to identify any early CT imaging features with prognostic significance in canine TBI patients. Limitations associated with CT may preclude its use for prognostication; however, modifications to the current MAIS and evaluation in a larger study population may yield more useful results. Despite this, CT is a valuable tool in the detection of structural abnormalities following TBI in dogs that warrants further investigation.

Neurological signs and MRI findings in 12 dogs with multiple myeloma.

Vertebral lesions and associated neurological signs occur in dogs with multiple myeloma, however, veterinary literature describing MRI findings is currently lacking. The objective of this multicenter, retrospective, case series study was to describe neurological signs and MRI findings in a group of dogs that presented for spinal pain or other neurological deficits and had multiple myeloma. Electronic records of four veterinary referral hospitals were reviewed. Dogs were included if they had a pathologically confirmed diagnosis of multiple myeloma, had presented for spinal pain or other neurological signs, and had undergone MRI of the vertebral column. The MRI studies were evaluated and the anatomical location of lesion(s), signal intensity, presence of extra-dural material, degree of spinal cord compression, extent of vertebral lesions, and contrast enhancement were recorded. Twelve dogs met inclusion criteria. Most dogs (n = 8) had a chronic progressive history, with varying degrees of proprioceptive ataxia and paresis (n = 11), and spinal pain was a feature in all dogs. The MRI findings were variable but more consistent features included the presence of multiple expansile vertebral lesions without extension beyond the outer cortical limits of affected vertebrae, and associated extradural material causing spinal cord compression. The majority of lesions were hyper- to isointense on T2 (n = 12) and T1-weighted (n = 8) sequences, with variable but homogeneous contrast-enhancement (n = 12). These described MRI characteristics of multiple myeloma may be used to aid early identification and guide subsequent confirmatory diagnostic steps, to ultimately improve therapeutic approach and long-term outcome.

NEUROLOGIC AND COMPUTED TOMOGRAPHY FINDINGS IN SEA TURTLES WITH HISTORY OF TRAUMATIC INJURY.

Boat strikes have been widely documented as a major cause of anthropogenic trauma and mortality in sea turtles. Axial trauma in these species involves the head and/or carapace and may cause severe damage to the nervous and pulmonary systems. The aims of this study were to develop an updated protocol for neurologic examinations in sea turtles, to describe computed tomography (CT) findings in sea turtles with sustained trauma, and to associate CT findings with neurologic status in sea turtles with and without traumatic injury. Ten sea turtles were examined, six green (Chelonia mydas) and four loggerhead (Caretta caretta) turtles: seven underwent neurologic and CT examinations, two had CT examinations only, and one had a neurologic examination only. The updated neurologic examination protocol was considered useful in differentiating normal from abnormal neurologic status, however some of these tests remain unreliable in sea turtles. Sea turtles with no history of trauma were found to have normal carapace shape, vertebral column, and neurologic status. Sea turtles with history of traumatic injury (more than 10 years prior to examination) had findings dependent on trauma site. Those with head trauma had variable presentations dependent on location of injury; while those with carapace trauma had varying degrees of kyphosis, lordosis, and scoliosis of the carapace, vertebral fractures, and paraparesis. Kyphosis of the carapace was associated with vertebral fractures detected on CT; however, the severity of vertebral abnormalities was not associated with the severity of neurologic deficits. These findings suggest that a combination of neurologic and CT examination may be beneficial in determining clinical significance of carapace deformation and associated neurologic deficits in sea turtles with traumatic injury.

Clinical signs, imaging findings, and outcome in twelve cats with internal ophthalmoparesis/ophthalmoplegia.

OBJECTIVE: To retrospectively evaluate the clinical signs, imaging findings, and outcome of feline internal ophthalmoparesis/ophthalmoplegia. PROCEDURE: Medical records were reviewed from 2008 to 2015. Inclusion criteria included cats that presented with internal ophthalmoparesis/ophthalmoplegia, underwent diagnostic imaging, and had follow-up information available. RESULTS: Twelve cases of feline internal ophthalmoparesis/ophthalmoplegia were identified. Nine cats were unilaterally affected, and three cats were bilaterally affected. Affected cats had a median age of 10.54 years (range 5.75 to 13.17), and both sexes of varying breeds were affected (nine males; three females). Clinical signs including abnormal mental status (n = 9; 75%) and additional neurologic abnormalities (n = 10; 83%) were observed. Magnetic resonance imaging and/or computed tomography (MRI/CT) of the head were performed in ten cats, revealing a mass lesion in all cases with varying locations. Multicentric lymphoma was diagnosed in two cats via abdominal ultrasound and cytology. All twelve cats were euthanized due to deterioration of clinical signs and/or quality-of-life concerns. Median time from diagnosis to euthanasia was 3.5 days (range 0 to 80 days). CONCLUSIONS: Feline internal ophthalmoparesis/ophthalmoplegia rarely presents as the sole clinical sign in a referral hospital. Advanced imaging (MRI/CT) may be necessary to reach a definitive diagnosis in these cases. However, abdominal ultrasound would be advocated in cats with systemic clinical signs as a less expensive and less invasive diagnostic test to further investigate the possible etiology of internal ophthalmoparesis/ophthalmoplegia prior to advanced imaging. Feline cases with internal ophthalmoparesis/ophthalmoplegia associated with other intracranial signs and/or systemic clinical signs have a poor prognosis.

IMAGING DIAGNOSIS-IMAGING AND HISTOPATHOLOGIC CHARACTERISTICS OF A VERTEBRAL HAMARTOMA IN A CAT.

A 9-month-old domestic shorthair cat had progressive ambulatory paraparesis, proprioceptive ataxia, and thoracolumbar hyperesthesia. An extradural mass affecting the left pedicle and lamina of the second lumbar vertebra (L2) causing marked spinal cord impingement was identified in magnetic resonance (MR) images. The mass was predominantly calcified in computed tomographic (CT) images. A hemilaminectomy was performed to resect the mass. Clinical signs were greatly improved at 12-month follow-up. The histopathologic diagnosis was vascular hamartoma. To our knowledge, this is the first report describing the MR characteristics of a vascular hamartoma associated with the vertebral column.

CLINICAL AND MAGNETIC RESONANCE IMAGING FEATURES OF IDIOPATHIC OCULOMOTOR NEUROPATHY IN 14 DOGS.

Ophthalmoplegia/ophthalmoparesis (internal, external, or both) has been reported in dogs secondary to neoplasia affecting the oculomotor nerve and is usually given a poor prognosis. The purpose of this retrospective study was to describe the clinical findings, magnetic resonance imaging (MRI) findings, management, outcome, and follow-up in a group of canine cases with idiopathic oculomotor neuropathy. Inclusion criteria included cases with ophthalmoplegia/ophthalmoparesis (internal, external or both) as sole neuroophthalmologic signs, complete ophthalmic and neurologic examination, head MRI, and a minimum follow-up period of 1 year. Dogs with progressive neurological signs not related to oculomotor neuropathy were excluded. Fourteen cases met the inclusion criteria. All cases were unilaterally affected. Magnetic resonance imaging showed equivocal enlargement of the oculomotor nerve in three cases, mild enlargement in five, and marked enlargement in six. Contrast enhancement was present in 12 cases, being marked in six. When present, the contrast enhancement was focal in eight cases and diffuse in four. The median follow-up time was 25 months. External ophthalmoparesis improved in seven cases, five cases under no treatment and two under systemic corticosteroid therapy. The clinical signs in the other seven cases remained unchanged. Idiopathic oculomotor neuropathy should be included as a differential diagnosis in dogs presenting with unilateral ophthalmoplegia/ophthalmoparesis (internal, external, or both) with the absence of other neurologic and ophthalmic signs, and with the MRI findings restricted to the oculomotor nerve. Idiopathic oculomotor neuropathy has a good prognosis as the clinical signs do not deteriorate and they can improve without treatment.

IMAGING DIAGNOSIS - UNILATERAL TRIGEMINAL NEURITIS MIMICKING PERIPHERAL NERVE SHEATH TUMOR IN A HORSE.

A 16-year old Warmblood gelding presented with a nonhealing corneal ulcer and absent corneal sensation in the left eye. A lesion affecting the maxillary and ophthalmic branches of the left trigeminal nerve was suspected. Magnetic resonance (MR) imaging identified marked thickening of the ophthalmic and maxillary branches of the left trigeminal nerve. The nerve was iso- to hypointense on T1-weighted and T2-weighted images with heterogeneous enhancement. A peripheral nerve sheath tumor was suspected, however granulomatous neuritis was histopathologically confirmed. These inflammatory changes can result in severe nerve enlargement and should be considered with MR findings suggestive of peripheral nerve sheath tumor.

CLINICAL AND MAGNETIC RESONANCE IMAGING CHARACTERISTICS OF THORACOLUMBAR INTERVERTEBRAL DISK EXTRUSIONS AND PROTRUSIONS IN LARGE BREED DOGS.

Treatment recommendations differ for dogs with intervertebral disk extrusion vs. intervertebral disk protrusion. The aim of this retrospective, cross-sectional study was to determine whether clinical and magnetic resonance imaging (MRI) variables could be used to predict a diagnosis of thoracolumbar intervertebral disk extrusion or protrusion in dogs. Dogs were included if they were large breed dogs, had an MRI study of the thoracolumbar or lumbar vertebral column, had undergone spinal surgery, and had the type of intervertebral disk herniation (intervertebral disk extrusion or protrusion) clearly stated in surgical reports. A veterinary neurologist unaware of surgical findings reviewed MRI studies and recorded number, location, degree of degeneration and morphology of intervertebral disks, presence of nuclear clefts, disk space narrowing, extent, localization and lateralization of herniated disk material, degree of spinal cord compression, intraparenchymal intensity changes, spondylosis deformans, spinal cord swelling, spinal cord atrophy, vertebral endplate changes, and presence of extradural hemorrhage. Ninety-five dogs were included in the sample. Multivariable statistical models indicated that longer duration of clinical signs (P = 0.01), midline instead of lateralized disk herniation (P = 0.007), and partial instead of complete disk degeneration (P = 0.01) were associated with a diagnosis of intervertebral disk protrusion. The presence of a single intervertebral herniation (P = 0.023) and dispersed intervertebral disk material not confined to the disk space (P = 0.06) made a diagnosis of intervertebral disk extrusion more likely. Findings from this study identified one clinical and four MRI variables that could potentially facilitate differentiating intervertebral disk extrusions from protrusions in dogs.

EVALUATION OF MAGNETIC RESONANCE IMAGING GUIDELINES FOR DIFFERENTIATION BETWEEN THORACOLUMBAR INTERVERTEBRAL DISK EXTRUSIONS AND INTERVERTEBRAL DISK PROTRUSIONS IN DOGS.

Four MRI variables have recently been suggested to be independently associated with a diagnosis of thoracolumbar intervertebral disk extrusion or protrusion. Midline intervertebral disk herniation, and partial intervertebral disk degeneration were associated with intervertebral disk protrusion, while presence of a single intervertebral disk herniation and disk material dispersed beyond the boundaries of the intervertebral disk space were associated with intervertebral disk extrusion. The aim of this retrospective, cross-sectional study was to determine whether using these MRI variables improves differentiation between thoracolumbar intervertebral disk extrusions and protrusions. Eighty large breed dogs with surgically confirmed thoracolumbar intervertebral disk extrusions or protrusions were included. Randomized MRI studies were presented on two occasions to six blinded observers, which were divided into three experience categories. During the first assessment, observers made a presumptive diagnosis of thoracolumbar intervertebral disk extrusion or protrusion without guidelines. During the second assessment they were asked to make a presumptive diagnosis with the aid of guidelines. Agreement was evaluated by Kappa-statistics. Diagnostic accuracy significantly improved from 70.8 to 79.6% and interobserver agreement for making a diagnosis of intervertebral disk extrusion or intervertebral disk protrusion improved from fair (κ = 0.27) to moderate (κ = 0.41) after using the proposed guidelines. Diagnostic accuracy was significantly influenced by degree of observer experience. Intraobserver agreement for the assessed variables ranged from fair to excellent and interobserver agreement ranged from fair to moderate. The results of this study suggest that the proposed imaging guidelines can aid in differentiating thoracolumbar intervertebral disk extrusions from protrusions.

Contralateral optic neuropathy and retinopathy associated with visual and afferent pupillomotor dysfunction following enucleation in six cats.

PURPOSE: To investigate contralateral optic neuropathy and retinopathy following enucleation in 6 cats. METHODS: Retrospective study. The medical records of cats with contralateral visual and afferent pupillomotor dysfunction following enucleation presented to the Animal Health Trust (AHT), Newmarket, UK, between January 1994 and January 2010 were reviewed. Information recorded included history, signalment, ophthalmic findings, electroretinography (ERG) (2/6) and MRI (3/6) findings and long-term outcome. Pearson's chi-square tests were used to compare breed proportions (P < 0.05). RESULTS: Six cats aged 1.5 to 11 (median 5.5) years presented with mydriasis and/or visual deficits noted immediately following enucleation. Enucleation involved optic nerve (ON) ligation in all of the four cases for which this information was available. Ophthalmic findings included mydriasis with absent pupillary light reflex (PLR) (4/6), incomplete PLRs (2/6), absence of dazzle reflex (4/6) and absence of menace response (4/6). Funduscopy initially revealed multifocal peripapillary retinal lesions, with subsequent progressive optic nerve head (ONH) and retinal atrophy. ERG recordings revealed normal outer retinal function at 6 and 22 weeks (2/2). On MRI, the optic chiasm (OC) ipsilateral to the enucleation could not be identified and the contralateral OC was atrophied (3/3). CONCLUSIONS: The acute afferent ON deficits following enucleation, progressive ONH atrophy, normal outer retinal function and MRI demonstrating OC pathology are consistent with chiasmal injury due to traction on the ON during enucleation. Rostral traction on the globe to facilitate ON ligation is contraindicated in cats.

Imaging diagnosis--Spontaneous subperiosteal vertebral hemorrhage in a greyhound.

A 4-year-old, spayed female greyhound dog was presented with an acute onset of paraplegia. There was no known history of trauma or coagulopathy. Spinal cord compression was identified on MRI. Intra-operative evaluation revealed the presence of a large subperiosteal hematoma and a smaller epidural hematoma. To the authors' knowledge, this is the first report of a spinal subperiosteal hematoma diagnosed antemortem through MRI, with surgical exploration and successful treatment in a dog.

Clinical presentation, diagnosis, treatment, and outcome in 8 dogs and 2 cats with global hypoxic-ischemic brain injury (2010-2022).

BACKGROUND: Global hypoxic-ischemic brain injury (GHIBI) results in variable degrees of neurological dysfunction. Limited data exists to guide prognostication on likelihood of functional recovery. HYPOTHESIS: Prolonged duration of hypoxic-ischemic insult and absence of neurological improvement in the first 72 hours are negative prognostic indicators. ANIMALS: Ten clinical cases with GHIBI. METHODS: Retrospective case series describing 8 dogs and 2 cats with GHIBI, including clinical signs, treatment, and outcome. RESULTS: Six dogs and 2 cats experienced cardiopulmonary arrest or anesthetic complication in a veterinary hospital and were promptly resuscitated. Seven showed progressive neurological improvement within 72 hours of the hypoxic-ischemic insult. Four fully recovered and 3 had residual neurological deficits. One dog presented comatose after resuscitation at the primary care practice. Magnetic resonance imaging confirmed diffuse cerebral cortical swelling and severe brainstem compression and the dog was euthanized. Two dogs suffered out-of-hospital cardiopulmonary arrest, secondary to a road traffic accident in 1 and laryngeal obstruction in the other. The first dog was euthanized after MRI that identified diffuse cerebral cortical swelling with severe brainstem compression. In the other dog, spontaneous circulation was recovered after 22 minutes of cardiopulmonary resuscitation. However, the dog remained blind, disorientated, and ambulatory tetraparetic with vestibular ataxia and was euthanized 58 days after presentation. Histopathological examination of the brain confirmed severe diffuse cerebral and cerebellar cortical necrosis. CONCLUSIONS AND CLINICAL IMPORTANCE: Duration of hypoxic-ischemic insult, diffuse brainstem involvement, MRI features, and rate of neurological recovery could provide indications of the likelihood of functional recovery after GHIBI.

Genome-wide mRNA sequencing of a single canine cerebellar cortical degeneration case leads to the identification of a disease associated SPTBN2 mutation.

BACKGROUND: Neonatal cerebellar cortical degeneration is a neurodegenerative disease described in several canine breeds including the Beagle. Affected Beagles are unable to ambulate normally from the onset of walking and the main pathological findings include Purkinje cell loss with swollen dendritic processes. Previous reports suggest an autosomal recessive mode of inheritance. The development of massively parallel sequencing techniques has presented the opportunity to investigate individual clinical cases using genome-wide sequencing approaches. We used genome-wide mRNA sequencing (mRNA-seq) of cerebellum tissue from a single Beagle with neonatal cerebellar cortical degeneration as a method of candidate gene sequencing, with the aim of identifying the causal mutation. RESULTS: A four-week old Beagle dog presented with progressive signs of cerebellar ataxia and the owner elected euthanasia. Histopathology revealed findings consistent with cerebellar cortical degeneration. Genome-wide mRNA sequencing (mRNA-seq) of RNA from cerebellum tissue was used as a method of candidate gene sequencing. After analysis of the canine orthologues of human spinocerebellar ataxia associated genes, we identified a homozygous 8 bp deletion in the ß-III spectrin gene, SPTBN2, associated with spinocerebellar type 5 in humans. Genotype analysis of the sire, dam, ten clinically unaffected siblings, and an affected sibling from a previous litter, showed the mutation to fully segregate with the disorder. Previous studies have shown that ß-III spectrin is critical for Purkinje cell development, and the absence of this protein can lead to cell damage through excitotoxicity, consistent with the observed Purkinje cell loss, degeneration of dendritic processes and associated neurological dysfunction in this Beagle. CONCLUSIONS: An 8 bp deletion in the SPTBN2 gene encoding ß-III spectrin is associated with neonatal cerebellar cortical degeneration in Beagle dogs. This study shows that mRNA-seq is a feasible method of screening candidate genes for mutations associated with rare diseases when a suitable tissue resource is available.

Clinical course of acute canine polyradiculoneuritis following treatment with human IV immunoglobulin.

Treatment of dogs with acute canine polyradiculoneuritis (ACP) is restricted to physical rehabilitation and supportive care. In humans with Guillain-Barré syndrome, the counterpart of ACP, randomized trials show that IV immunoglobulin (IVIg) speeds recovery. The authors of the current study hypothesized that dogs with ACP would tolerate IVIg well and recover faster than dogs managed with supportive treatment only. Sixteen client-owned dogs with ACP were treated with IVIg, and 14 client-owned dogs served as a retrospective control group. Diagnosis was confirmed using clinical features, electrodiagnostics, cerebrospinal fluid analysis, and muscle/nerve biopsies. The duration of the initial progressive phase, the time from IVIg administration until the dogs were ambulating without assistance, and the duration of the complete episode were evaluated. Adverse reactions (anaphylaxis, mild hematuria) were observed in two dogs. Dogs treated with IVIg were ambulating without assistance after a median of 27.5 days (range, 15-127 days) from onset of clinical signs. The control group was ambulatory without assistance at a median of 75.5 days (range, 5-220 days). Even though this result is not statistically significant, there is a clear trend toward faster recovery in dogs treated with IVIg.

Multicenter Study of Clinical Presentation, Treatment, and Outcome in 41 Dogs With Spinal Epidural Empyema.

There is limited information on canine spinal epidural empyema (SEE). The aim of this multicenter retrospective study is to describe the clinical presentation and outcome of dogs undergoing spinal surgery or conservative management for SEE. Forty-one dogs met the inclusion criteria; the SEE was treated surgically in 17 dogs and conservatively in 24 dogs. Two dogs underwent spinal surgery after failure of conservative management, meaning that 19 dogs in total had spinal surgery. Long-term (i.e., >6 months) follow-up was available in 35 dogs (19 conservatively treated and 16 surgically treated dogs). Recovery to a functional pet status was achieved in 15/19 (78.9%) conservatively treated and 12/16 (75%) surgically treated dogs. There was no significant difference (p = 1.000) in long-term outcome between conservatively and surgically treated dogs (78.9 and 75%, respectively). However, significantly more surgically treated dogs were non-ambulatory at presentation (9/17 vs. 5/24, p = 0.048) compared with conservatively treated dogs. This study suggests that conservative treatment may be appropriate for dogs with SEE that are ambulatory at presentation and that surgically treated dogs generally have good outcomes. Age may be a negative prognostic indicator as dogs with poor long-term outcomes were significantly older than dogs with a good long-term outcome (p = 0.048). A larger prospective randomized study may provide further insight on treatment and outcome of SEE in dogs.

Disseminated mast cell tumor infiltrating the sphenoid bone and causing blindness in a dog.

Mast cell tumors are found in most organs and tissues with variable biologic behavior in dogs. This case illustrates the clinical and magnetic resonance imaging (MRI) findings in a dog with disseminated mast cell tumor infiltrating the sphenoid bones. A 6-year-old male neutered Greyhound presented with a 3-day history of acute onset of blindness. General physical examination was normal. Neurological examination revealed mildly disorientated mental status, absent menace response in both eyes, bilaterally decreased vestibulo-oculocephalic reflexes and absent direct and consensual pupillary light reflex in both eyes. An electroretinogram indicated normal retinal function in both eyes. A lesion involving the middle and rostral cranial fossa was suspected. Hematology and serum biochemistry were normal except decreased urea (1.2 mmol/L). MRI of the head revealed heterogeneous signal intensity of the sphenoid bones on T2-weighted images and loss of their normal internal architecture. Cerebrospinal fluid analysis was normal. Abdominal ultrasound revealed hepatosplenomegaly and mesenteric lymphadenopathy. Fine needle aspirates were taken from the jejunal lymph nodes and the spleen. Results were consistent with disseminated mast cell tumor. The owner declined any treatment and the dog was euthanatized. Postmortem examination confirmed disseminated mast cell tumor affecting multiple organs, including the sphenoid bones. To our knowledge, this is the first case describing MRI features of disseminated mast cell tumor affecting the sphenoid bones and causing acute onset of blindness in a dog.

Traumatic skull fractures in dogs and cats: A comparative analysis of neurological and computed tomographic features.

BACKGROUND: Traumatic skull fractures (TSF) are relatively frequent in dogs and cats, but little information is available regarding their clinical and imaging features. HYPOTHESIS/OBJECTIVES: To describe the neurological and computed tomographic (CT) features of a large cohort of dogs and cats with TSF. ANIMALS: Ninety-one dogs and 95 cats with TSF identified on CT. METHODS: Multicenter retrospective comparative study. Signalment, cause of trauma, fracture locations and characteristics, presence of neurological deficits, and 1-week survival were recorded. Fractures were classified according to the extent of fragmentation and displacement. RESULTS: The cranial vault was affected more frequently in dogs (P = .003), whereas the face and base of the cranium more often was affected in cats (P < .001). Cats presented with multiple fractures more frequently (P < .001). All animals with TSF in the cranial vault were more likely to develop neurological signs (P = .02), especially when depressed fractures were present (95% confidence interval [CI], 1.7-8.2; P = .001). Animals with TSF located only in the facial region were less likely to have neurological signs (odds ratio with Mantel-Haenszel's method [ORMH ], 0.2; 95% CI, 0.1-0.6; P = .004). Most affected animals (84.9%) survived the first week post-trauma. Death was more likely with fractures of the cranial vault (P = .003), especially when fragmented (P = .007) and displaced (P = .004). CONCLUSIONS AND CLINICAL IMPORTANCE: Traumatic skull fracture distribution and patterns are different between dogs and cats. Cranial vault fractures were associated with neurological deficits and worse survival. The presence of TSF alone should not be considered a negative prognostic factor because most affected animals survived the first week.