Traumatic and iatrogenic sciatic nerve injury in 38 dogs and 10 cats: Clinical and electrodiagnostic findings.

BACKGROUND: Reports describing sciatic nerve injuries (SNI) and their outcome are scarce in veterinary medicine. HYPOTHESIS: Describe the causes of traumatic and iatrogenic SNI and evaluate which clinical and electrodiagnostic findings predict outcome. ANIMALS: Thirty-eight dogs and 10 cats with confirmed SNI referred for neurologic and electrodiagnostic evaluation. METHODS: Clinical and electrodiagnostic examination results, including electromyography (EMG), motor nerve conduction studies, muscle-evoked potential (MEP), F-waves, sensory nerve conduction studies, and cord dorsum potential (CDP), were retrospectively evaluated. Quality of life (QoL) was assessed based on owner interviews. RESULTS: Surgery (42%) and trauma (33%) were the most common causes of SNI; in dogs, 24% were caused by bites from wild boars. Ability to flex and extend the tarsus was significantly associated with positive outcome in dogs. Mean time from onset of clinical signs until electrodiagnostic evaluation was 67 ± 65 (range, 7-300) days and 65 ± 108 (range, 7-365) days for dogs and cats, respectively. A cut-off amplitude of 1.45 mV for compound motor action potentials (CMAP) was predictive of positive outcome in dogs (P = .01), with sensitivity of 58% and specificity of 100%. CONCLUSIONS AND CLINICAL IMPORTANCE: Clinical motor function predicts recovery better than sensory function. Electrodiagnostic findings also may play a role in predicting the outcome of SNI. Application of the proposed CMAP cut-off amplitude may assist clinicians in shortening the time to reassessment or for earlier suggestion of salvage procedures. Owners perceived a good quality of life (QoL), even in cases of hindlimb amputation.

Artifacts During Short-Term Interictal Electroencephalographic Recording in Dogs.

The electroencephalogram (EEG) is an electrodiagnostic technique widely used in both scientific research and clinical medicine. It makes it possible to study the neurophysiology of brain activity by recording real-time changes in electrical potential produced by cortical activation. The importance of EEG in diagnosing canine epilepsy demonstrates its usefulness when the owner's description of crises is not clear or when the episodes cannot be differentiated from behavioral or cardiac disorders. However, EEG recordings also often record electrical activity from sources other than the brain, which may interfere with the clinical event-related signal. This activity is known as artifactual electrical activity, and the signal changes recorded in these cases corrupt the trace when they are superimposed on brain activity or even, in some cases, mimic pathologic abnormalities. The first step in analyzing and interpreting EEG traces is to recognize artifacts and other specific transient events. This retrospective study set out to ascertain whether artifacts comparable to those described in humans are observed in protocols used to perform short-term interictal EEG for canine epilepsy and how these can be classified.

Epidural dirofilariosis in a paraparetic cat: case report of Dirofilaria immitis infection.

A 6-year-old neutered female cat was examined for chronic and progressive pelvic limb ataxia that progressed to non-ambulatory paraparesis over 1 month. Haematological and serum analyses were mainly within normal ranges. Thoracic and abdominal radiographs did not reveal any morphological abnormalities. Magnetic resonance imaging investigation of the thoraco-lumbar spine demonstrated a well-defined, extradural mass that extended into the epidural space from the L2 to L3 vertebral bodies and expanded in the L2 to L3 left intervertebral foramen. During surgery, a long, narrow, white parasite which was weakly adherent to the phlogistic epidural fat tissue was gently removed from the spinal canal. Histological examination of the pathological tissue supported a diagnosis of epidural steatitis surrounding a female adult Dirofilaria immitis. This is a novel case of natural D immitis infection with spinal localisation in a cat, well documented with magnetic resonance investigation, and cytological and histological examinations, introducing a novel differential diagnosis for extradural spinal masses in cats.