Praha & EU: Investujeme do vaší budoucnosti Evropský sociální fond. Principles of general neurology

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1 Principles of general neurology

2 The 1 st week Mon - Wed General neurology Thur Fri Paediatric neurology Disorders of consciousness The 2 nd week Mon Strokes Tue Parkinson s disease and syndromes Wed Dyskinesias Thur Epilepsy Fri Meningitis, encephalitis, myelitis, radiculoneuritis

3 The 3 rd week Mon Tue Wed Thur Neuromuscular diseases and neuropathies Neuro-oncology Traumatic brain injuries, spinal cord injuries Multiple sclerosis Fri Spinal disorders and basic compression syndromes of peripheral nerve The 4 th week Mon Tue Wed Thur Fri Sleep disorders Pain Dementia Paediatric neurology Propedaedeutic examination + EXAM

4 Lectures dex.php?page=prezentace_5r

5 Medical history Diagnostic algortihm Neurological examination Interpretation of acquired data - formulating clinical suspicion Indication of relevant auxiliary investigative techniques with clearly formulated presumption Exception: traumatic injury, altered consciousness

6 Interpretation of acquired data - formulating clinical suspicion Syndromologic (semiologic) diagnosis: summary of individual symptoms/signs of disease clustered in characteristic combination Topical diagnosis: level of lesion within the neural systém Nosological diagnosis: clinical entity (disease) characterized by neurological syndrome, along with clinical course, treatment response etc. Etiological diagnosis: cause of neural lesion, often special targeted examination methods are necessarily indicated

7 Basic terms Symptom: individual presentation Syndrome: 2 a more symptoms present together in an individual in characteristic combination (important for topology, e.g. parkinsonian syndrome lesion of basal ganglia, or for pathogenesis, e.g. meningism indicates inflammation of meninges)

8 Basic terms Praha & EU: Investujeme do vaší budoucnosti Paresis: decrease in muscular strength, partial paralysis Plegia: loss of muscle strength, complete paralysis monoparesis: one limb affected diparesis: 2 limbs affected triparesis: 3 limbs affected quadriparesis: all limbs affected hemiparesis: limbs of one body side affected (left / right) paraparesis: both lower limbs affected

9 Basic terms Superficial sensation - algic and thermic (spinothalamic pathway): algic - pain thermic heat, cold Superficial sensation - tactile (posterior funicles and spinothalamic pathway): tactile touch, dicriminative... Deep sensation (posterior funicles): pallesthesia = capability of sensing vibrations proprioception, kinesthesia =capability of sensing position, direction and changes of movement speed

10 Basic terms anesthesia: complete loss of sensation in respective body part hypesthesia: reduced sensationi hyperesthesia: enhanced sensation paresthesia: abnormal somatosensory perception in absence of external stimulus (spontaneous pins and needles, freezing, burning etc.) dysesthesia: erroneous perception of real somatosensory stimulus (touch as burning, heat as cold etc.) allodynia: painful sensation induced by stimulus that is not usually associated with pain

11 Peripheral and central nervous system

12 Muscle Levels of peripheral nervous system Neuromuscular junction Peripheral nerve (motor-sensitive-mixed) Plexus Roots: (dorsal root, ventral root, combined root lesion) Peripheral (caudal) motor neuron

13 Levels of central nervous system Spinal cord Brain Infratentorial area Supratentorial area -brainstem -cerebellum -white matter of hemispheres -thalamus -basal ganglia -cortex

14 Basal differences between peripheral and central lesion Parameter Peripheral lesion Central lesion Deep tendon reflexes Muscle tone Pyramidal signs - + Disordered sensation + (radic. area, nerv.) + (large regions) Muscle atrophy + - (late, from Fasciculations + inactivity) - Muscle weakness +(radic. area, nerv.) + (large regions)

15 Peripheral lesion flaccid paresis Central lesion - spastic paresis Pseudoflaccid stage: first 2-3 weeks after acute lesion of pyramidal pathways - hypotonia and areflexia (parallel to spinal shock)

16 Peripheral lesion

17 Muscle lesion clinical characterization Muscle weakness (localization depends on distribution of ( proximal affected muscles, more often atrophy, hypotrophy, pseudohypertrophy hypotonia reduced (but may be also adequate) stretch proprioceptive reflexes absent disorder of sensation but pain may be present ( rhabdomyolysis (myositis, ( climb (myopatic

18 Disorders of neuromuscular junction ( pattern (myasthenic muscular fatigue, weakness depending on preceding physical effort Praha & EU: Investujeme do vaší budoucnosti no sensory deficit no pain normal muscle tone normal proprioceptive reflexes normal muscle mass (-trophy)

19 Lesion of peripheral nerve muscle weakness in area nervina distribution disorder of sensation in area nervina or glove-like, sock-like distribution (not always present depends whether the nerve with sensitive component is affected) Pain may be present

20 Areae nervorum

21 Areae nervorum

22 Diffuse lesion of peripheral nerves muscle weakness that doesn t correspond to particular area nervina (most often acral localization) frequently present after sensation disorder altered sensation in glove-/sock-like distribution (not always present depends on the fact whether the nerve with sensitive component is affected) pain may be present Etiology: diffuse lesion (inflammatory, metabolic )

23 Lesion of plexus Muscle weakness and hypotonia Altered sensation in distribution noncorresponding to area nervina, radicularis (larger, several segments)

24 Radicular lesion Lesion of dorsal root sensory disorder pain in distribution of area radicularis no muscle weakness no fasciculations Lesion of ventral root muscle weakness in distribution of area radicularis fasciculation no sensory disorder no pain Lesion of lower motor neuron muscle weakness and hypotonia in distribution of damaged neurons otherwise identical to ventral root lesion

25 Radicular lesion Sensory neurons dorsal root Innervated skin area = dermatome alpha motor neurons in anterior horns of spinal cord axons form ventral root project through plexus and peripheral nerves into muscle groups = myotome

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28 Chipault s rule Spines of Segment upper C vertebrae - identical lower C vertabrea upper Th vertabrae lower Th vertebra Th10-Th12 - L Trans.: Th12-L1 - epiconus vertebra L1 - conus Diagram of root exit points

29 Syndrome of cauda ( disc (common in prolapsed Irritative Severe pain in assymetric radicular distribution Destructive Assymetric disorder of sensation - radicular distribution ( roots Areflexia (corresponding to affected ( roots Weakness (corresponding to affected Sphincter disturbance

30 MRI sequestrum CT prolapse

31 Syndrome of conus, epiconus: vertebral body level: Th12-L1 Conus (S3-5) often tumor, traumatic injury Altered perianogenital sensation Urinary retention, fecal incontinence Erectile dysfunction No marked pain Bilateral symmetric presentation Epiconus The same as in conus +weakness of plantar, dorsal flexion of foot, areflexia L5-S2

32 conus, epiconus

33 Central lesion spinal cord

34 Image of spinal cord

35 General characteristics of spinal cord lesions Lesion of spinal cord Motor disorders Peripheral paresis in affected segment Central paresis under the affected segment Posture stability and gait disturbances Altered sensation Sphincter dysfunction (retention or incontinence) Backache and constrictive sensations in certain segments

36 Transversal lesion of spinal cord Plegia distally from the localization of lesion (Acute: spinal shock plegia - hypotonia, absent pyramidal signs etc. - duration: hours to weeks) Combined with peripheral paralysis according to localization (Lesions above C5 are not compatible with life without artificial ventilation.) Anesthesia distally from the localization of lesion (sometimes hyperesthesia on the margin of anesthesia)!margin of sensation! Sphincter dysfunctions Acute: Retention of urine or paradoxical ischuria Chronic: automatic (spinal) bladder

37 SPINAL SYNDROMES: central cord syndrome :

38 Focal spinal cords pathologies Central cord syndrome The most common causes: traumatic injury, tumor or ischemia. Basic characterization Bilateral disruption of algic, heat and cold sensitivity within affected segments, with continual spread in caudal direction, usually with sacral preservation. Syringomyelic dissociation of sensitivity Later development of peripheral paresis on the level of affected segments (lesion of motor neurons).

39 Diagram of sensitive pathways

40 syringomyelia

41 Intramedular tumor

42 Focal pathologies of spinal cord anterolateral syndrome The most common cause: ischemia. Basic characterization Peripheral paresis on the level of affected segments. Central paresis caudally from lesion level - results from lesion of descendent pathways. Sensation of heat, cold and algic stimuli is affected. Preserved tactile and deep sensory functions.

43 Image of anterolateral lesion.

44 Focal pathologies of spinal cord Brown-Sequard s syndrome (unilateral) The most common cause: traumatic injury. Basic characterization: On the homolateral side: Peripheral paresis on the level of lesion central paresis below the lesion Sensory disturbance deep and tactile On the contralateral side: No motor disorder Disrupted sensory f. heat, cold, algic (incipient typically on the level lower by 2-3 segments)

45 Diagram of Brown.Séquard s syndrome

46 Posterior column syndrome (tabic syndrome) The most common cause: neurosyphilis, metabolic diseases (diabetes mellitus) Basic characterization No paresis Ataxia, areflexia Loss of deep and also (partially) tactile sensory functions - below the lesion level. Algic and thermic sensory functions are preserved but with common occurence of paresthesias and shooting pains.

47 Posterior and lateral columns syndrome The most common cause: Friedreich s disease, other degenerative diseases, deficiency of vit. B12. Basic characterization: central (spastic) paresis, characteristic spasticatactic gait ataxia (from disruption of proprioception and cerebellar ataxia from lesion of spinocerebellar pathways) Disruption of deep and tactile sensory functions. Preserved algic and thermic sensory f.

48 Expansive process arising from the bone and compressing spinal cord.

49 Identification of lesion level Patient with paraparesis of the lower limbs L2-S2 increased, C5-8 normal i.e.: lesion above L2 and under C8 More precise identification: Limit margin of sensory changes Event. Calculation according to Chippault s rule Patient with peripheral paresis of the upper limbs and central paresis of the lower limbs lesion C5-8 Patient with central quadriparesis without lesion of cranial nerves C1-C4 (C4-phrenic n. threatening of vital f.)

50 Central lesions the brain

51 Cerebral lesions clinical characterization General presentation headache altered consciousness generalized epileptic paroxysms intracranial hypertension Praha & EU: Investujeme do vaší budoucnosti Focal signs focal neurological deficit focal epileptic paroxysms affected cranial nerves speech disturbances and other cognitive dysfunctions

52 Infratentorial region Clinical characterization Lesion of cranial nerves Altered consciousness Alternating pattern of hemiparesis or sensory disturbance (peripheral lesion of cranial nerves on the contralateral side to hemiparesis) Hemi- or quadri-paresis, sensory disturbance Nausea, vomiting, vertigo Nystagmus Disorder of posture, stability and gait Disruption of upper limb coordination

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55 Brainstem localization of motor pathway: alternating hemiplegias/paresis ( alternantes (hemiplegiae Mesencephalon (n. III): superior alternating hemiplegia (Weber) Pons (n. VI a VII): middle alternating hemiplegia (Millard-Gubler) Oblongata (n. XII): inferior alternating hemiplegia (Déjerine)

56 alternating hemiparesis

57 Bulbar syndrome (. VII Lesion of nuclei of nn. IX. XII. bilaterally (+ V. a Dysarthria, dysphagia Lingual atrophy with fasciculations, depression of soft palate, extinct gag reflex, extinct masseter r. ( muscles (+ paresis of facial

58 Pseudobulbar syndrome Bilateral lesion of corticonuclear (corticobulbar) pathway heading to motor nuclei of nn. IX. XII. Dysphagia, dysarthria Tongue without atrophy, fasciculations Present masseter r., gag r. spastic : signsemotional+ laughter and cry

59 Peripheral paresis of facial nerve Lesion of peripheral nerve anywhere within its length Paresis or plegia of the whole homolateral half of the face Smoothed wrinkles on the forehead and inability to close the eye Smoothed nasolabial sulcus and drooping mouth corner Etiology: passage of facial nerve through petrose bone, often viral etiology Above the branching of chorda tympani hypogeusia on anterior 2/3s of tongue Above the branching of stapedius n. hyperacusia

60 Central paresis of facial nerve Supranuclear lesion of corticobulbar pathway Paresis of facial muscles in the lower half of the face, contralaterally: Drooping of the corner of the mouth Smoothed nasolabial sulcus Disruption of showing teeth, whistling Weakness of platysma Etiology: frequent presentation of stroke on the contralateral side

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62 Syndrome of pontocerebellar angle Hypacusis, tinnitus, vertigo Peripheral paresis of n. VII. Unilateral extinction of corneal r. Cerebellar syndrome Etiology: Schwannoma of n. VIII., meningiomas

63 Neurinoma of n. VIII

64 Cerebellum Physiological functions Regulation of muscle tone balance Movement coordination Movement course and targeting, positioning of body segments, recruitment of muscle groups during the movement

65 Structure and functions of cerebellum ( floculonodularis Archicerebellum (pars vestibular afferents - balance ( lobe Paleocerebellum (vermis, tonsils, anterior Spinal afferents muscle tone ( hemispheres Neocerebellum (most of Cortical afferents movement coordination

66 Paleocerebellar syndrome ( disequilibrium Axial ataxia (axial astasia uncertain standing with wide basis, deviations, falls without side preference abasia uncertainty when walking, widen basis, deviations, falls without side preference large asynergy dysfunction of axial muscles coordination improper measuring of movements during standing up, sitting, rising titubation swaying tremor of the head and upper trunk dysarthria

67 Neocerebellar syndrome Limb ataxia, ipsilateral to affected cerebellar hemisphere hypermetria dysdiadochokinesis little asynergy intention tremor hypotonia increased passiveness, excursion range of joints

68 Vestibular apparatus Physiological functions Balance Regulation of muscle tone Coordination of movements of the head and eyes

69 Inner ear: function and structure Hearing Cochlea: Corti s organ Balance vestibule: saccule, utricle and 3 semicircular canals with with wide ampullas registrate changes of head position in the gravitational field and linear acceleration Hairy cells react to movements of endolymph, to gravity or to acoustic vibrations

70 Saccule, utricle: Changes of head position in gravitational field, linear acceleration. Hairy cells are located in maculas of saccule and utricle. In maculas are located so-called otoliths - crystals of calcium carbonate that bend the cilia during change of head position by the effect of gravity.

71 Vestibular syndromes Subjective symptoms: vertigo, nausea Objective signs: Nystagmus Balance disorder Tonic deviations of the trunk and limbs

72 Nystagmus Involuntary fast movements of both eyeballs with slow (pathological) and fast (compensatory) component. Nystagmus results from disruption of vestibular system and its neural connections. Direction Determined by fast component (horizontal, rotational, vertical, combined etc.) Intensity I. grade: present only when looking in direction of the fast component II. grade: apparent in forward gaze as well III. grade: persisting even when looking on the opposite side

73 Peripheral harmonic vestibular syndrome Logical relation of nystagmus direction to the direction of tonic vestibular deviations (fast component of nystagmus tends ( deviations against direction of Tonic deviations depend on the head position Concomitant symptoms: often hypacusis and tinnitus Nystagmus type: horizontal rotational, doesn t change the direction Level of lesion: Labyrinth Vestibular n. in the petrose bone, pontocerebellar angle Entrance areas of vestibular nuclei Etiology: BPPV, labyrinthitis, Menier s disease etc.

74 Central - dysharmonic vestibular syndrome The direction of nystagmus and that of tonic deviations are not logically related. E.g. only nystagmus with vertigo and minimal stability disorder may dominate Nystagmus may be in the same direction as tonic vestibular deviations. Frequent changes of direction and intensity. Praha & EU: Investujeme do vaší budoucnosti Accompanying symptoms: sometimes other brainstem sy Type of nystagmus: simply rotational, vertical, diagonal etc. Level of lesion: brainstem (FLM) and vestibular cerebellum Etiology: demyelination, vascular, parainfectious

75 Differentiation between peripheral and central vestibular syndrome Peripheral Central (harmonic) (dysharmonic) Intensity of vertigo high mild, moderate Nystagmus one direction changes direction Tonic deviation one direction variable direction Compensation relatively fast slow, difficult Other symptoms auditory brainstem

76 Supratentorial region of the brain

77 Cortex Supratentorial region Disorders of speech (frontal and temporal lobes) Disorders of practic and gnostic functions (parietal lobes) Behaviour disorders (prefrontal areas of frontal lobes, temporal lobes) hemianopsia (occipital lobes) epileptic paroxysms (character of paroxysm depends on the localization of focus) Pareses and sensory disorders (area of central sulcus) Long pathways Sy of internal capsule (capsula interna) Hemiparesis Hemi-distributed sensory disorders

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79 Diagram of internal capsule

80 Lesions of internal capsule - symptoms Contralateral spastic hemiplegia/paresis including nn. XII a VII. ( type (Wernicke-Mann s Contralateral hemianopsoa Contralateral hemianesthesia (Bilateral lesion: pseudobulbar syndrome in the F portion: spastic laughter and cry and ( symptoms pseudocerebellar

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82 Basal ganglia caudate nc. putamen gl. pallidus subthalamic nc. ncl. accumbens ncl. basalis Meynerti related nuclei: amygdala thalamus subst. nigra ncl. ruber pedunculopontine nc.

83 Basal ganglia functional connections Major neurotransmitters: Dopamine Glutamate GABA Acetylcholine Neuropeptides and others

84 Basal gangla major functions Body posture Regulation of muscle tone Coordination of voluntary and automatic movements Creating movement programs, triggering and timing movements, adjustment of movements to external conditions emotionality, cognitive functions, mental integration

85 Extrapyramidal syndromes Hypokinetic (parkinsonian, hypokinetic-rigid, hypokinetic-hypertonic) Hyperkinetic tremor chorea dystonia myoclonus tic

86 Thalamus Rellay station last information interlink before entrance to cortex Integration of sensory, motor, vegetative neural activity Dominating symptoms depend on the localization within thalamus Motor disorders: ataxia, tremor, dystonia Sensory disorders: hemihypesthesia, anaesthesia dolorosa Thalamic pain; Altered consciousness Emotional changes, memory disturbances

87 Cortex Primary cortical centres Secondary association areas (unimodal association cortex) Tertiary association areas (multimodal association areas) Posterior parietal area (perception and speech) Limbic area (emotions and memory) Anterior (prefrontal) area (planning of movements)

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90 Disruptions of cortical areas Primary sensory areas local anesthesia amaurosis deafness Primary motor areas plegia, paresis

91 Disorders of associative cortical areas Unimodal and multimodal association areas Gnostic functions agnosia Practic functions apraxia Phatic functions aphasia

92 Disorders of language and speech language system of expression and communication means of symbolic character speech motor production of verbal sounds Acquired neurogenic disorders of using language - aphasia, cognitive communication disorder (in ( dementia Acquired neurogenic disorders of speech dysarthria, speech apraxia Diagnosis and therapy of language and speech disorders - logopedy

93 Aphasia Acquired disorder of language (stroke in the territory of internal carotid a., tumor, traumatic head injury) Focal lesion of brain Lesion especially in cortical areas (or event. in subcortical areas - thalamus and basal ganglia) Lesions of dominant hemisphere

94 Classification of aphasia Fluent (fluent speech) formerly sensory aphasia - posterior lesion - behind central sulcus Nonfluent formerly motor aphasia - anterior lesion - in front of central sulcus global aphasia (formerly mixed ) caused by extensive lesion of dominant hemisphere Boston classification the most used classification of aphasia in the world; enables to classify more than ¾ of aphasias

95 Symptoms of aphasia Disordered speech fluency Disordered comprehension Disordered naming Disordered repeating Perseverations Disorders of reading, writing

96 Symptoms of aphasia alexia disorders of reading agraphia disorders of writing Disorder of loud reading (often similar symptoms as in spontaneous speech) Disorder of understanding the text Disorders of reading and writing may occur also separatedly without aphasia

97 Dysarthria Disorders of speech (disorders of comprehension, naming, forming sentence structure or using grammar are not present )

98 Dysarthria results from: paresis disrupted muscle tone disordered coordination of muscles involved in speech production lesion of motor system leading to dysarthria anywhere along the pathway from the brain to the particular muscle. Contrary from aphasia not primarily cortical disorder!

99 Dysarthria cerebellar (atactic) Lesion of cerebellum and its pathways extrapyramidal-hypokinetic Lesions of basal ganglia, extrapyramidal pathways