Neurological workup or what a neurologist does for a living Anatomy & Physiology Spring 2016 Stan Misler Making a diagnosis A 75 year old gentleman is referred to a neurologist for progressive loss of memory over two years. Does the patient have a neurological disease and is so which of the three major neurological disturbances in his age group (dementia, stroke or Parkinsons disease) is the patient presenting with? How can he be helped? 1. What can be gained by watching and listening to patient as he enters office? He walks into office unaided and with no apparent gait disturbance He is overheard talking to his son fluently and making sense Hence he is awake and alert with no gross movement disorder He is dressed well and sits and gets out of chair easily His question sheet, filled out by son, states he is seen by his primary care physician every 6 months, is on no medications, has had no episodes of loss of consciousness, no brain imaging (CT or MRI, and no weight change His vital signs checked by nurse are BP 130/80, pulse 75 (both sitting and standing) and regular for a minute, temp 37oC; oxygen saturation = 97%. He is 510, standing straight and weighing = 170 lb Left hemispheric stroke (CVA): spastic paralysis Primary motor cortex stroke 2 years after onset : hemiplegia (one sided weakness on side opposite to CVA) with spasticity (hyperreflexia and rigidity), stiff extended leg & poor use of fingers. Often comes with sudden aphasia (inability to speak), dysphasia (difficulty saying words) or talking non-sense or with new onset of unilateral poor vision. Most often associated with damage to middle cerebral artery. Parkinsonism = Paralysis agitans: tremor, rigidity; bradykinesis; abnormal postural readjustments Basal ganglia deficient in neurotransmitter dopamine -> limitation of motor output; Use of precursor L-dopa as treatment CNS control of voluntary movement a. Malice of forethought: Guess where is the lesion is from minimal information Lower motor neuron injury -> flaccid paralysis Upper motor neuron (pyramidal system) injury -> spastic paralysis (stroke) Basal ganglia injury -> movement disorders (Parkinsons) Cerebellum -> ataxia Ocular motor system injury -> loss of conjugate gaze Somatosensory system injury -> anesthesia and analgesia Visual system injury -> anopsia Auditory system injury -> deafness Gustatory and olfactory system injury -> ageusia and anosmia Cerebral cortex injury -> aphasia, agnosia and apraxia (Stroke) Limbic system injury -> antegrade amnesia and inappropriate behavior (dementia) Hypothalamic injury -> vegetative and endocrine imbalance Brainstem injuries -> Disorders of arousal or responsiveness Autonomic nervous system injury -> visceral abnormalities Disorder of blood supply to CNS -> stroke Disorder of cerebrospinal fluid system -> hydrocephalus 2. Interview Patients presenting complaint (sometimes only elicited from caregiver): old or new (hours vs. years); acute episodes or chronic with stepwise progression; one-sided or symmetrical. Associated symptoms: change in behavior; fatigue vs. specific weakness, change in balance; numbness and tingling; fever; seizures; slurred speech; tremor Level of function at home or work Past medical history: cardiac, lung, cancers (particularly with metastases), head and neck injuries Medication and street drug history Mental status exam 3. Neurological exam overview Mental status (including mini mental status exam): Assess state of consciousness ranging from unconscious and incapable of being aroused, to alert and attentive, to hyperexcitable; assess memory, speech and language; mood. [Normal speech requires selection of words (intellectual processing); motor coordination of speech centers; respiratory control; adjustment of musculature of palate and face] Reflex activity and muscle tone and strength: function of spinal and brainstem and nerves arising from them as well as intactness of muscle Sensory processing: vision; hearing; somatic sensations (touch; pain; temperature; vibration; proprioception = limb or joint position sense); taste and smell Cranial nerve exam Voluntary Motor patterns: posture, coordination & gait (motor loops) vs. involuntary movements (seizures) Portions of general medical exam depending on neurological finding Whishing sounds over partially blocked arteries Displaced skull bones, clear fluid dripping from ear or nose Pain on bending head to chest Swollen optic disc as key to pressure in skull Key to lower spinal cord compression Blood pressure lying down and standing Level of responsiveness Trapping of sciatic nerve Evidence for motor cortex injury (upper motor neuron = pyramidal track) Evidence for cerebellar lesions Finger to nose dysmetria Dementia Wide range of symptoms, lasting at least 6 months, associated with decline in memory, especially short term, and other cognitive skills (communication and language; ability to focus and pay attention without restlessness and impulsivity; reasoning and judgment without memory distortions or emotional lability) usually severe enough to reduce persons ability to perform daily activities. The latter include keeping track of wallet, keys, paying bills, planning and preparing meals; remembering appointments and traveling out of immediate neighborhood all of which worsen in the evening (sundowning). Consciousness (awareness), movements and basic bodily functions (swallowing, balance, bowel and bladder control) are usually not effected until late in disease. Diagnosis is based on history, detailed interview and mini-mental status exam (score < 23) and may be confirmed by brain imaging (CT or MRI of brain atrophy) or brain biopsy. Incidence increases with aging after 65 but is not caused by aging. More than one etiology (cause) may be present. Affects 40 million people Most frequent cause is Alzheimers disease (60 70% of cases) where protein collections (amyloid protein) outside and inside of cells causing brain atrophy (soft shrunken cortex) and reduced synaptic communication in the hippocampus (center of learning and memory). Initially patient has good judgment and ability to reason but fails at naming objects. Later, he repeats the same question or phrase. In Alzheimers there is no cure or specific treatment but onset of disease and slowed progression may be delayed by mental exercises, physical exercise and Mediterranean diet of dec red meat, and inc. whole grains, fruits and vegetables, fish, nuts and olive oil. Less frequent causes are (i) vascular deficiency in hippocampus and thalamus, as after a multiple small strokes (vascular or multi-infarct dementia) (20%), (ii) frontotemporal dementia (5%) with early drastic personality and language changes but preserved short term memory, and (iii) traumatic brain injury as after repeated concussions. In vascular dementia recurrent strokes may be prevented by control of blood pressure, glucose and cholesterol. Dementia can also be caused or worsened by reversible conditions in 10% of cases. These include depression; side effects of medication especially those taken for chronic pain; excessive use of alcohol; reduced thyroid function; untreated AIDs; liver or kidney failure; vitamin B12 or folate deficiency; untreated syphilis; following anesthesia or concurrent with long-standing infection (meningitis); long term sleep deprivation and normal pressure hydrocephalus (NPH = decreased absorption of cerebrospinal fluid with dilated ventricle resulting as well in gait disturbance = unsteadiness as walking on a boat and urinary incontinence or wet, wobbly and wacky). These conditions which can be diagnosed by specific blood tests or brain imaging. NPH can be treated with a ventriculo-peritoneal shunt. All of these causes are opposed to long term benign forgetfulness of senescence or abrupt confusion as during hospitalization in an intensive care unit Education and emotional and physical support to caregivers are needed for patient to be cared for at home. Adult day care is often critical in allowing caregiver to function (respite care) 6. Lumbar puncture and CSF analysis Measure opening pressure (elevated in hemorrhage and brain tumor); observe for clarity and color); send CSF to lab for glucose, and protein concentrations, cell count, culture and to rule out meningitis What diagnostic work up might you do to assess the causes of dementia? Huge ventricles in NPH Amyloid deposits in mild cognitive impairment (MCI+) and advanced Alzheimers disease (AD) Enrichment: Brain lesions from CVAs Left leg weakness and clumsiness and left alien hand Talking non-sense New onset poor vision