Clinical,Magnetic Resonance Imaging,and Histopathologic Findings in 6 Dogs with Surgically resected Extraparenchymal Spinal Cord Hematomas

Background

Extraparenchymal spinal cord hematoma has been described in veterinary medicine in association with neoplasia, intervertebral disk disease, and snake envenomation. There are rare reports of spontaneous extraparenchymal spinal cord hematoma formation with no known cause in human medicine. Multiple cases of spontaneous extraparenchymal spinal cord hematoma have not been described previously in veterinary medicine.

Objectives

To describe the signalment, clinical findings, magnetic resonance imaging (MRI) features, and surgical outcomes in histopathologically confirmed extraparenchymal spinal cord hematomas in dogs with no identified underlying etiology.

Animals

Six dogs had MRI of the spinal cord, decompressive spinal surgery, and histopathologic confirmation of extraparenchymal spinal cord hematoma not associated with an underlying cause.

Methods

Multi‐institutional retrospective study.

Results

Six patients had spontaneous extraparenchymal spinal cord hematoma formation. MRI showed normal signal within the spinal cord parenchyma in all patients. All hematomas had T2‐weighted hyperintensity and the majority (5/6) had no contrast enhancement. All dogs underwent surgical decompression and most patients (5/6) returned to normal or near normal neurologic function postoperatively. Follow‐up of the patients (ranging between 921 and 1,446 days) showed no progression of neurologic clinical signs or any conditions associated with increased bleeding tendency.

Conclusions and Clinical Importance

Before surgery and histopathology confirming extraparenchymal hematoma, the primary differential in most cases was neoplasia, based on the MRI findings. This retrospective study reminds clinicians of the importance of the combination of advanced imaging combined with histopathologic diagnosis. The prognosis for spontaneous spinal cord extraparenchymal hematoma with surgical decompression appears to be favorable in most cases.     

Use Of Traction During Magnetic Resonance Imaging Of Caudal Cervical Spondylomyelopathy ("Wobbler Syndrome") In The Dog

Cervical spondylomyelopathy or "wobbler syndrome" is a well-defined disorder of large-breed dogs, characterized by a compressive lesion affecting the cervical spinal cord that in many dogs may have a dynamic component. Determination of whether this dynamic component is present is important in the decision-making process as regards therapeutic intervention. Despite a significant risk of neurologic deterioration following myelography in some large dogs affected by wobbler syndrome, myelography is considered an essential part of the assessment, primarily as it allows assessment of whether a dynamic compression exists. This same neurologic deterioration is not apparent following magnetic resonance (MR) imaging; however, the use of MR imaging in the investigation of wobbler syndrome has thus far been limited by the inability to perform the traction studies required to ascertain whether a dynamic component to the spinal cord compression exists. This paper presents a technique of applying traction during MR imaging of the cervical spine to reduce a dynamic wobbler syndrome lesion.     

Clinical Features and Magnetic Resonance Imaging Findings in 7 Dogs with Central Nervous System Aspergillosis

Background

Systemic aspergillosis is a manifestation of Aspergillus sp. infection that can result in central nervous system (CNS) involvement with marked alterations in CNS function. Information regarding the clinical presentation and magnetic resonance imaging (MRI) findings in cases of aspergillosis with CNS involvement is lacking, resulting in a need for better understanding of this disease.

Hypothesis/Objectives

The primary objectives were to describe the clinical features and MRI findings in dogs with CNS aspergillosis. The secondary objectives were to describe clinicopathologic findings and case outcome.

Animals

Seven dogs with CNS aspergillosis.

Methods

Archived records from 6 institutions were reviewed to identify cases with MRI of CNS aspergillosis confirmed with serum galactomannan enzyme immunoassay (EIA) testing, culture, or supported by histopathology. Signalment, clinical, MRI, clinicopathologic, histopathologic, and microbiologic findings were recorded and evaluated.

Results

Aspergillosis of the CNS was identified in 7 dogs from 3 institutions. The median age was 3 years and six were German Shepherd dogs. Five dogs had signs of vestibular dysfunction as a component of multifocal neurological abnormalities. The MRI findings ranged from normal to abnormal, including hemorrhagic infarction and mass lesions.

Conclusions and Clinical Importance

Until now, all reported MRI findings in dogs with CNS aspergillosis have been abnormal. We document that CNS aspergillosis in dogs, particularly German Shepherd dogs, can be suspected based on neurologic signs, whether MRI findings are normal or abnormal. Confirmatory testing with galactomannan EIA, urine, cerebrospinal fluid (CSF) or tissue culture should be performed in cases where aspergillosis is a differential diagnosis.     

Computed Tomography and Magnetic Resonance Imaging of an Epidermoid Cyst in a Foot of a Horse

An 18-year-old Quarter Horse mare was evaluated because of moderate left forelimb lameness of 4 weeks’ duration. The clinical evaluation and diagnostic perineural analgesia localized the lameness to the distal portion of the left forelimb. There was swelling on the dorsal and lateral aspect of the coronary band. Radiography, ultrasound, magnetic resonance imaging, and computed tomography of the foot revealed circumscribed well-capsulated soft tissue mass causing a focal deformation of the dorsolateral border of the middle phalanx. The treatment aimed to remove the mass surgically and stabilized the interphalangeal joint, but the owner elected human euthanasia before treatment attempt. Histopathology diagnosis was an epidermoid cyst, which was characterized by multilayers of keratin surrounded by stratified squamous epithelium. Although rare, an epidermoid cyst should be considered as a differential diagnosis for space-occupying mass in horses’ foot that develops chronic lameness after trauma. This report describes the multimodality appearance of the epidermoid cyst.     

Two‐Year Follow‐Up Magnetic Resonance Imaging and Spectroscopy Findings and Cerebrospinal Fluid Analysis of a Dog with Sandhoff's Disease

A 13‐month‐old female Toy Poodle was presented for progressive ataxia and intention tremors of head movement. The diagnosis of Sandhoff's disease (GM2 gangliosidosis) was confirmed by deficient β‐N‐acetylhexosaminidase A and B activity in circulating leukocytes and identification of the homozygous mutation (HEXB: c.283delG). White matter in the cerebrum and cerebellum was hyperintense on T2‐weighted and fluid‐attenuated inversion recovery magnetic resonance images. Over the next 2 years, the white matter lesions expanded, and bilateral lesions appeared in the cerebellum and thalamus, associated with clinical deterioration. Magnetic resonance spectroscopy showed progressive decrease in brain N‐acetylaspartate, and glycine‐myo‐inositol and lactate‐alanine were increased in the terminal clinical stage. The concentrations of myelin basic protein and neuron specific enolase in cerebrospinal fluid were persistently increased. Imaging and spectroscopic appearance correlated with histopathological findings of severe myelin loss in cerebral and cerebellar white matter and destruction of the majority of cerebral and cerebellar neurons.     

犬瘟热的诊疗及血细胞变化监测

患犬经临床检查和实验室检验确诊为犬瘟热.综合采用抗病毒、抗菌、对症治疗和支持疗法,并对诊疗过程中患犬的血细胞变化进行了监测;患犬康复后留有抽搐后遗症.     

Clinical and Pathological Findings in Testis, Epididymis, Deferens Duct and Prostate following Vasectomy in a Dog

We report the case of a bilateral and multilocular spermatocele and sperm granuloma in a dog that was vasectomized 5 years before. Clinical examination revealed scrotal dermatitis and benign prostatic hyperplasia. Orchiectomy was performed, and gross and histological examination showed testicular degeneration associated with epididymal sperm granuloma. In relation to this case, the literature about long-term effects of vasectomy in dogs has been reviewed. On the basis of these results, a preventive sonogram and physical assessment in prostate and other reproductive structures before vasectomy is recommended.     

Neocortical Astrocytoma in a Dog: Behavioural and Clinico-Pathological Findings

Abstract— —An astrocytoma in a 9-year-old Boxer dog was found on postmortem to have invaded the sensory and motor regions of the neocortex in the right cerebrum. The limbic lobe, internal capsule and corpus callosum were also involved. Clinical symptoms included hyperaesthesia on left side of the body, poor placing response in left fore-leg, convulsions and circling away from the affected side. EEG revealed focal spike discharges which were localized around the cortical area affected.
Résumé— —Chez un chien boxer âgé de 9 ans, un astrocytome a été trouvéà l'autopsie, ayant invadé les régions sensorielle et motrice du néocortex dans le cerveau droit. Le lobe limbique, la capsule interne et le corps calleux étaient également impliqués. Les symptomes cliniques incluaient l'hyperesthésie de la région droite, mauvaise réaction de placement de la patte antérieure gauche, convulsions et tournement de côté de la région affectée. EEG révéla des décharges pointues focales localisées autour de la région corticale affectée.
Zusammenfassung— — Ein Astrocytom bei einer 9 Jahre alten Bulldogge wurde bei der Sektion gefunden. Dieses war in die sensorischen und motorischen Regionen des Neopallium im rechten Gehirn eingedrungen. Der limbische Lappen, die innere Kapsel und das Corpus callosum waren ebenfalls beteiligt. Die klinischen Symptome bestanden in Hyperaesthesie der linken Kärperhölfte, schlechte Bewegungen im linken Vorderbein, Konvulsionen und Fortbewegungen von der betroffenen Seite. EEG zeigte fokale Aehren-Entladungen, die in der betroffenen Rindenzone lokalisient wurden.     

Radiography,Computed Tomography and Magnetic Resonance Imaging of Craniofacial Structures in Pig

The pig has recently become popular as a large animal experimental model in many fields of biomedical research. The aim of this study is to evaluate the basic anatomical structures in the head region of the pig to lay the groundwork for its practical clinical usage or pre‐clinical research in the future. We used three different diagnostic imaging methods: radiography, computed tomography (CT) and magnetic resonance imaging (MRI). The analysis showed that radiographic imaging is suitable only for general evaluation of the facial area of the pig skull. CT images showed excellent spatial definition of bony structures of the whole craniofacial area, and MRI images revealed fine soft tissue details. Radiography is preferentially suited to general assessment of bone structures of the facial skeleton; however, the thick layer of adipose tissue in the craniofacial region of the pig makes the imaging of some parts difficult or even impossible. CT is useful for revealing morphological details of mineralized tissues, whereas MRI is more suitable for soft tissue analysis and the detection of subtle pathologic changes in both bone and soft tissues. Therefore, before using pigs as an experimental model in craniofacial research, it is necessary to evaluate the suitability and disadvantages of potential imaging methods and how appropriate they are for accurate visualization of desired structures.     

Unusual Navicular Bone Fractures in HindLimbs: Clinical and Imaging Findings

Three horses were identified with an unusual fracture configuration of a hindlimb navicular bone. All horses had unilateral lameness which was worse on a circle on a firm surface and was abolished by plantar nerve blocks performed at the base of the proximal sesamoid bones. Radiological findings included an ill-defined curvilinear radiolucent line along the distal horizontal border of the navicular bone in case 1; cases 2 and 3 had three fragments along the distal horizontal border, associated, in case 2, with marked abnormalities extending into the spongiosa of the bone. Lesions in case 2 were bilateral despite unilateral lameness. Fractures parallel to the distal horizontal border of the navicular bone have not been described in front limbs; neither have more than two fragments been observed along the distal border. One previous report describes a lesion similar to that in case 1 in a hindlimb navicular bone. Fragmentation of the distal horizontal border associated with rupture of the distal sesamoidean impar ligament and proximal displacement of the bone has been reported in hindlimbs. It is likely that biomechanical reasons are responsible for the occurrence of these lesions in hindlimbs.     

A Short-tailed Demodectic Mite and Demodex canis Infestation in a Chihuahua Dog

Abstract— Infestation with short-tailed demodectic mites and Demodex canis was diagnosed in an 8-month-old male Chihuahua dog. Skin lesions were characterized by alopecia and scaling on the ventral aspects of the chest, all four limbs, the ventral aspect of the neck and around the eyes. Both Demodex canis and a short-tailed demodectic mite were observed on skin scrapings. After 4 months of amitraz dip treatments, skin scrapings were negative and hair regrowth appeared.
Résumé— Une infestation à Demodex (forme courte) et à Demodex canis est diagnostiquée sur un Chihuahua, mâle de 8 mois. Les lésions cutanées sont caractérisées par une alopécie squameuse du thorax, des quatre membres, du cou et autour des yeux. Les raclages cutanés montrent la présence de Demodex canis et de Demodex sp. (forme courte). Après 4 mois de traitement à l'amitraz, les raclages cutanés sont négatifs et une repousse des poils est observée. [Chen, C. A short-tailed demodectic mite and Demodex canis infestation in a Chihuahua dog (Infestation à Demodex canis et à Demodex (forme courte) chez un Chihuahua).