Neurolocalization Assessing Deficits

IEUROLOCALIZATION ASSESSING DEFICITS I - OLFACTORY Difficult to assess PUPILLARY LIGHT REFLEX MENACE RESPONSE can try hiding food Must assess in dark/ambient Learned response by 12 in hand or under weeks; not reflex light first Assess for anisicoria Hand is moved quickly II - OPTIC Miotic? towards eye; stopped before Example: If the right eye is mydriadic, and you shine a light in the right Lesions along visual Constricted? eye and the left eye constricts, then the lesion location is to the hitting occulomotor nerve on the right. pathway can affect Mydriatic? Example: If the right eye is mydriadic, and you shine a light in the right will assess CN II & VII eye and neither eye constricts but when you shine it on the left and both Several ways to Horner syndrome eyes constrict, then the lesion location is to the pre-chiasmal on the right. assess Lack of sympathetic innervation to head UMN LMN and neck Miosis Detrusor Muscle Increased Decreased Ptosis Tone Enopthalmos 3rd eyelid elevation Urethral Sphincter Increased Decreased Vasodilation Tone Bladder Expression Difficult - urinary Easy - urinary REFLEXES retention incontinence An animal will NEVER have a normal exam C1-C5 T3-L3 other than reflexes which Respiratory depression Schiff Sherrington lead to neurolocalization C6-T2 Spinal Shock Horner syndrome Cuteous Trunci Cutoff Nerve root signature L4-S3 WITHDRAWAL REFLEX Absent Cutaneous Trunci Abnormal anal tone Thoracic Limb Flaccid tail Sensory of toes = caudal intumescence Motor for flexion is cranial intumescence Lesion anywhere in C6-T2 could influence VII - FACIAL withdrawal Lack of menace or palpebral Pelvic Limb facial drooping Lack of sensation to inner Deep pain medial digit = femoral nerve Sensory to rest = sciatic pinnae Motor for flexion is entire intumescence Neurogenic keratoconjunctivitis Lesion anywhere in L4-S1 could influence sicca withdrawal PAW PLACEMENT VIII - VESTIBULOCOCHLEAR IX, X, XI - GLOSSOPHARYNGEAL, Maintains posture and balance VAGUS, SPINAL ACCESSORY Minimal strength required Detects acceleration and Pure cerebellar lesions do All originate from caudal deceleration not affect medulla Forebrain lesions can cause Coordinates eye movement MOTOR of swallowing: IX, X, XI Clinical signs of impingement SENSORY of swallowing: X delayed to absent paw can include placement Forebrain lesions can Abnormal posture XII - HYPOGLOSSAL Vestibular ataxia frequently have normal- Strabismus Inspect tongue for atrophy, mildly delayed hopping but asymmetry or deviation Nystagmus absent paw placement Heating loss is hard to assess Animals lick nose after gag Cerebellar can have normal reflex is tested unless deaf in both ears paw placement but absent watching animal drink water hoppping can also help assess Brainstem and spinal cord have delayed to absent of both