Infectious neuromuscular diseases of dogs and cats.

Neuromuscular diseases are disorders that affect peripheral nerve, neuromuscular junction, or muscle. Inflammatory diseases of the neuromuscular system can be further classified as infectious or noninfectious (presumed immune-mediated) diseases. The purpose of this article is to describe the more commonly reported infectious diseases that affect the neuromuscular system of dogs and cats.

CT-guided stereotactic brain biopsy using the Kopf stereotactic system.

This report describes computed tomography (CT)-guided stereotactic brain biopsy using the Kopf stereotactic system, a commercially available patient restraint system which does not require additional modification for use in small animals. The accuracy of biopsy needle placement was determined by injecting dilute iohexol into cadaver brains and comparing the three-dimensional coordinates of the desired target location to the actual needle tract observed on postcontrast CT images. Overall mean error in needle placement in a dorsoventral trajectory was 0.9 +/- 0.9 mm (n = 80 injections) for dogs and 1.0 +/- 1.1 mm (n = 30 injections) for cats. The overall mean error in needle placement via an oblique trajectory in five dogs was 1.7 +/- 1.6 mm (n = 12 injections). These results suggest that this system can be used to successfully place a biopsy needle into the brain to obtain biopsies from small lesions.

Fibrocartilaginous embolic myelopathy in five cats.

Five cats had clinical signs, radiographic findings, and cerebrospinal fluid analyses consistent with fibrocartilaginous embolic myelopathy. All cats had an acute onset of nonpainful, asymmetrical spinal cord signs (paresis or paralysis of one or more limbs). Magnetic resonance imaging was performed in three cats. On T2-weighted images, an intramedullary lesion was revealed that was hyperintense to normal spinal cord gray matter. On T1-weighted images, the lesion was isointense. Three of the cats were euthanized, and postmortem examination confirmed myelomalacia with intralesional fibrocartilaginous emboli. Two cats survived and were clinically improved within 3 weeks.

Signs of neurologic dysfunction in dogs with central versus peripheral vestibular disease.

OBJECTIVE: To determine the frequency of specific signs of neurologic dysfunction in dogs with central vestibular disease (CVD) or peripheral vestibular disease (PVD) and whether the degree of head tilt, rate of nystagmus, and number of beats of postrotatory nystagmus can be used to help distinguish CVD from PVD. DESIGN: Prospective clinical study. ANIMALS: 40 client-owned dogs with vestibular system dysfunction. PROCEDURE: A standard neurologic examination was performed, along with an expanded vestibular system examination that assessed the degree of head tilt, rate of nystagmus, and number of beats of postrotatory nystagmus. RESULTS: Dogs with CVD were significantly more likely to be nonambulatory than were dogs with PVD. Dogs with PVD were significantly more likely to veer or lean in 1 direction and to have resting nystagmus than were dogs with CVD. Median rate of resting nystagmus was significantly higher for dogs with PVD, but no significant differences between groups were detected in regard to presence or degree of head tilt, presence of positional ventral strabismus, and number of beats of postrotatory nystagmus. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that nonambulatory tetraparesis is significantly more common in dogs with CVD and veering and leaning are significantly more common in dogs with PVD. Although neither the degree of head tilt nor the number of beats of postrotatory nystagmus could be used to distinguish CVD from PVD, rate of resting nystagmus may be useful in distinguishing the 2 conditions.

Magnetic resonance imaging features of feline intracranial neoplasia: retrospective analysis of 46 cats.

The purpose of this retrospective study was to determine the magnetic resonance imaging (MRI) characteristics of feline brain tumors and to determine whether these characteristics can be used to accurately predict the histologic diagnosis. MRI scans of 46 cats with histologically confirmed brain tumors were reviewed, including 33 meningiomas, 6 lymphomas, 4 gliomas, 2 olfactory neuroblastomas, and 1 pituitary tumor. MRI features including axial origin, shape, location, signal intensity, contrast enhancement, peritumoral edema, and mass effect were reviewed and characterized for each tumor type. Tumor shape, axial origin, contrast enhancement, and degree of peritumoral edema aided in the identification of tumor type. Meningiomas were always extra-axial and were most often ovoid with marked contrast enhancement and mild peritumoral edema. Gliomas were always intra-axial with ring enhancement and generally caused more peritumoral edema than other tumors. The brain tumor was detected on MRI in 45 (98%) cats. Two blinded independent reviewers correctly identified 82% of all of the tumor types on the basis of MRI appearance alone. Thus, MRI is an excellent diagnostic tool for the detection of brain tumors in cats, and it provides important information to aid in the diagnosis of tumor type.

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001).

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.

Congenital factor XI deficiency in a domestic shorthair cat.

A 6-month-old, female, domestic shorthair cat was examined after onychectomy and ovariohysterectomy because of bleeding from the paws. Prolonged activated partial thromboplastin time was discovered, Coagulation factor analyses revealed deficiency of factor XI coagulant activity. Plasma mixing studies indicated factor deficiency or dysfunction rather than factor inhibition. Feline factor XI deficiency in one adult cat has been previously reported but was attributed to factor XI inhibitors. The signalment, lack of primary disease, and the finding of persistent factor XI deficiency in the absence of coagulation inhibitors were considered compatible with congenital factor XI deficiency in the cat of this report.

Severe hematometra in a dog with cystic endometrial hyperplasia/pyometra complex.

An 18-month-old, intact female German shepherd dog was presented for evaluation of severe, frank hemorrhage from the vulva. A complete blood count, serum biochemical analysis, and urinalysis supported acute hemorrhage. Abdominal radiographs were unremarkable. Abdominal ultrasound demonstrated that the uterine body and cranial vaginal lumen were fluid-filled and contained hyperechoic, polypoid masses that were suspected to be blood clots. Exploratory laparotomy revealed a mildly enlarged uterus with a diffuse, cystic endometrium; significant amounts of blood and blood clots within the lumen; and several focal accumulations of yellow fluid presumed to be a purulent exudate. Histopathology confirmed severe, cystic, endometrial hyperplasia and pyometra complex.