Decompressive craniectomy surgery in a dog with intracranial extradural hematoma following blunt force trauma.

A young miniature poodle was presented following blunt force trauma to the head. The dog initially responded well to medical management before developing clinical signs associated with increased intracranial pressure 48 h post-injury that became refractory to hyperosmolar therapy. A computed tomography scan obtained 76 h post-injury showed a short, oblique, non-displaced, complete fissure in the right temporal bone and a second short, oblique, non-displaced, complete fissure in the ventral aspect of the temporal bone. A biconvex, moderately hyperattenuating, space-occupying temporoparietal lesion was visualized immediately adjacent to the area of the temporal fractures. These findings were consistent with a diagnosis of intracranial extradural hematoma. Decompressive craniectomy successfully evacuated the extradural hematoma to alleviate increased intracranial pressure. The dog's neurologic function recovered quickly postoperatively. At follow-up physical examinations at 14 and 437 d, excellent return to function was noted. Key clinical message: This report describes the diagnosis and surgical management of an intracranial extradural hematoma in a dog with increased intracranial pressure refractory to medical management. Furthermore, this report describes the diagnostic imaging findings used to diagnose this particular form of primary brain injury.

Chirurgie de craniectomie décompressive chez un chien présentant un hématome extradural intracrânien à la suite d'un traumatisme contondant. Un jeune caniche miniature a été présenté à la suite d'un traumatisme contondant à la tête. Le chien a initialement bien répondu à la prise en charge médicale avant de développer des signes cliniques associés à une augmentation de la pression intracrânienne 48 heures après la blessure, qui sont devenus réfractaires au traitement hyperosmolaire. Une tomodensitométrie obtenue 76 heures après la blessure a montré une fissure complète courte, oblique, non déplacée dans l'os temporal droit et une deuxième fissure complète courte, oblique, non déplacée dans la face ventrale de l'os temporal. Une lésion temporo-pariétale biconvexe, modérément hyperatténuée et occupant de l'espace a été visualisée immédiatement à côté de la zone des fractures temporales. Ces résultats concordaient avec un diagnostic d'hématome extradural intracrânien. La craniectomie décompressive a réussi à évacuer l'hématome extradural pour atténuer l'augmentation de la pression intracrânienne. La fonction neurologique du chien s'est rétablie rapidement après l'opération. Lors des examens physiques de suivi à 14 et 437 jours, un excellent retour au fonctionnement a été noté.Message clinique clé:Ce rapport décrit le diagnostic et la prise en charge chirurgicale d'un hématome extradural intracrânien chez un chien présentant une augmentation de la pression intracrânienne réfractaire à la prise en charge médicale. En outre, ce rapport décrit les résultats de l'imagerie diagnostique utilisée pour diagnostiquer cette forme particulière de lésion cérébrale primaire.(Traduit par Dr Serge Messier).

Surgical treatment of a traumatic intracranial epidural haematoma in a dog.

A 10-month-old Czech wolf dog was unconscious after being kicked in the head by a horse. The following day, the dog was ataxic and collapsed after several steps. The level of consciousness was decreased. Cranial nerve examination was normal and right postural reactions were decreased. Spinal reflexes were intact in all limbs. The diagnostic work-up included a computed tomography (CT) scan of the head with IV contrast. A lenticular shaped, hyperdense, non-enhancing lesion was observed in the left fronto-parietal region. A diagnosis of intracranial epidural haematoma was made. Two craniotomies were performed on a different day and most of the haematoma was removed. Corticosteroids and antimicrobial therapy were administered. Fifteen days after the surgery, the clinical examinations were unremarkable. Fifteen months later, the owners considered the dog normal. Intracranial subdural or intraparenchymal haematomas have been described in the veterinary literature. To the authors' knowledge, this is the first report of the successful management of an intracranial epidural haematoma in the dog. In humans, these lesions are well described. Common locations are temporal, parietal and frontal regions or a combination of these regions. Patients can be asymptomatic, present with varying clinical signs, or be unconscious. Based on the human literature, following trauma to the head, a CT scan should be performed even if the patient is asymptomatic. Some authors believe that there are not any absolute indications for conservative management versus surgical management.

Paresis secondary to an extradural hematoma in a Sumatran tiger (Panthera tigris sumatrae).

A 15-yr-old female Sumatran tiger (Panthera tigris sumatrae) was presented to the Boren Veterinary Medical Teaching Hospital at Oklahoma State University with a 3-wk history of progressive hind limb weakness. Neurologic evaluation was limited to review of videotape that demonstrated weakness and ataxia with conscious proprioceptive deficits of the tiger's pelvic limbs. Spinal radiography demonstrated disc space narrowing, and myelography demonstrated a large extradural compressive lesion at the level of L2-3. Computed tomography did not reveal bone involvement. Surgery was performed to decompress the spinal cord and obtain a definitive diagnosis. A right hemilaminectomy was performed after a dorsal approach to the lumbar spine. Histologic examination of the mass revealed a consolidated extradural spinal hematoma, presumed to be secondary to intervertebral disc herniation. Despite incomplete resection of the mass and plastic deformation of the spinal cord, the tiger returned to normal ambulation within 3 wk of surgical decompression.

The computed tomographic appearance of acute thoracolumbar intervertebral disc herniations in dogs.

The appearance of herniated intervertebral disc material in the thoracolumbar vertebral canal was evaluated in 23 dogs using computed tomography (CT). The images were then compared with the myelographic and surgical findings. The normal spinal cord, outlined by epidural fat over intervertebral disc spaces, was of intermediate attenuation on transverse CT images. Herniated disc material was identified in all animals as a heterogeneous hyperattenuating extradural mass. The attenuation of the disc material increased with the degree of mineralization. In seven dogs, the herniated material was only slightly more attenuating than the spinal cord. In these dogs, small fragments of mineralized disc material and significant hemorrhage were found in the epidural space at surgery. In dogs with a long standing history of disc herniations, disc material identified in the vertebral canal had a more hyperattenuating and homogeneous appearance than recently herniated disc material. We conclude that mineralized, herniated disc material and hemorrhage can be identified quickly and safely in dogs using CT.

Potential central nervous system complications of von Willebrand's disease.

Three Doberman pinschers were presented on emergency referral for progressive neurological deficits. All three dogs had a similar onset of clinical signs associated with an apparently minor traumatic event. Each dog progressed to significant neurological dysfunction including paraplegia, tetraplegia, and/or loss of deep pain sensation. None of the animals was apparently affected by cervical vertebral instability ("Wobbler's Syndrome"). All were confirmed to have von Willebrand's disease. In all cases, significant epidural hemorrhage was identified. The etiology of each hemorrhage, however, was different for each animal. The cases presented here demonstrate a potential relationship between neurological deficits and the patient's ability to effectively coagulate blood. Hemostatic abnormalities, such as von Willebrand's disease, should be included as possible differential diagnoses or contributing factors in animals demonstrating neurological deficits. These abnormalities should especially be considered following trauma, intervertebral disk extrusion, or spinal surgery.

Meningeal haemorrhage and congestion associated with the perinatal mortality of foals.

A high frequency of meningeal lesions was found at autopsy in foals dying perinatally. Such lesions are considered an index of injury to the fetal central nervous system, from trauma and/or hypoxia during birth. Their incidence in the sample examined (26 foals) is similar to that observed in the perinatal mortality of lambs and calves.