Presentation on theme: "Sensory Stimulation in Neurological Rehabilitation"— Presentation transcript:
1 Sensory Stimulation in Neurological Rehabilitation Prof. A.V. SRINIVASAN.M.D, D.M, PhD,F.I.A.N, F.A.A.NEMERITUS PROFESSOR OF NEUROLOGYFORMER HEAD AND PROFESSOR OF NEUROLOGYInstitute of NeurologyChennaiThe sign wasn’t placed thereBy the Big Printer in the skySensory StimulationinNeurological Rehabilitation
5 Thomas Elbert Basic Principles Cortical representation expands linearly with use.Synchronous inputs lead to fusion of cortical zonesAsynchronous inputs lead to segregation of cortical zones.Disuse or De-afferentation leads to invasion ofunused cortical area by nearby neurons.
6 Sensory modulation in spatial neglect Novel TechniquesPeripheral somatosensory- Magnetic stimulationRepetitive optokinetic stimulationNeck Vibration trainingDrug Treatment is currently unsuccessful
7 Sensory modulation and Stroke Rehabilitation aimed to increase use of paretic handVirtual realityMotor imageryProf. V.S..Ramachandran’s virtual reality boxPhantom limb phenomenon
8 Other techniques Caloric tests for balance Brings awareness of illness to patient.Kinesthetic, visual, and auditory cues to improve Parkinsonian gait.
9 INTERMANUAL REFERRAL OF SENSATION AND EXTINCTION OF PAIN IN PERIPHERAL AND CENTRAL LESIONS OF SOMATO SENSORY SYSTEM
10 BACKGROUNDAllesthesia and extinction of referral sensation in brachial plexus lesionsA.V. Srinivasan and V.S. Ramachandran et al (1998)Intermanual referral of sensations after central lesions of the somato sensory systemK. Sathian et al (2000)
11 METHODS 8 patients (19-51 years) Brachial plexus lesion – one Amputation – twoStroke – fivePatients were video filmed in the movement disorder clinic. Pinprick, cold, vibration and kinesthesis were testedMRI & ENMG in all cases
12 CENTRAL LESION Stroke Thalamic stroke - three Temparo parietal - two Three to four months laterIpsilateral arm - no referral to leg
13 STROKE Contd…Intense pressure on the normal hand resulted in extinction of pain in the stroke sidePain returned within one minute of the pressureIntense pressure improved sensory and motor phenomenon
14 AMPUTATIONBoth the patients (below elbow & knee amputation) showed intermanual referral of sensation within 10 days. The referred sensations of touch and vibration lacked spatial organization and poor localization with a relatively high threshold
15 CASE VIGNETTE (BRACHIAL PLEXUS LESION) 21 year old girl, after total brachial plexus lesion was examined 6 months, 1 ½ & 2 ½ years after the lesionShe had sensations intermanually referred in a topographically organized manner in the phantom limb
16 INTERMANUAL REFERAL AND EXTINCTION OF PAIN SENSATION Hemiparesis with hemisensory deficitAmputationBrachial plexusSpatial organi-sationPoorExcellentLocalisationGoodTime of occuranceAfter 3 to 4 monthsImmediate with in 7 daysImmediate with in 7daysPainExtinctionAfter a delay of3 - 5 secondsImmediate
17 DISCUSSION Anatomical facts In 2a & 2b the receptive fields are larger 1. Primary somato sensory area 3b2. A. Primary somato sensory area 1 & 22. B. Second somato sensory cortex andparietal operculumIn 2a & 2b the receptive fields are largerbilateral and callosal connection areabundant
18 DISCUSSION Contd…Contralateral referral of sensations was not found in normal subjects or in hemiparetic patients without hemi sensory lossNeural mechanisms for perceptual alteration not clear
19 DISCUSSION Contd…It appears that a decrease in somatosensory input to one cerebral hemisphere from the contralateral hand allows responsiveness of neurons in this hemisphere to moderately intense tactile stimuli on the ipsilateral hand to exceed perceptual threshold (which does not normally occur).
20 CONCLUSIONIntermanual referral & extinction of pain occurred immediately in amputation and brachial plexus lesions and after a delay in strokeIntermanual referral of sensation occurred topographicaly organised manner in brachial plexus lesions but not in amputation and stroke
21 Hemineglect An Interesting Case from Prof.A.V.Srinivasan’s Unit
22 Can the mind believe what the eye sees ? On vision, visuospatial dysfunction and body image perception in right hemispherical dysfunctionDr.K.Bijoy Menon (Senior Resident)Dr.Sundar, Dr.Saravanan, Dr.RamakrishnanDr.Nithyanandan (Asst.Prof) ,Prof. A.V.Srinivasan
23 We thank Prof. V.S.Ramachandran, M.D., Ph.D., Director Centre for Brain and Cognitive SciencesUniversity of California, San Diego, USA
24 Indrani. 50 year old female Presents with sudden onset of weakness of left upper and lower limbO/E.Conscious, oriented to time, place and personMild left UMN facial paresisLeft hemiplegiaAll peripheral pulses palpable
25 CT Brain – P – Shows a (R) Occipitotemporal infarct
26 Higher mental function evaluation MMSE : 28/30She was very attentive and quite clear in her conversation with us, though she would be complaining of a vague left sided shoulder painOn lobar testing, she hadLeft visual neglect with (L) hemianopiaNo auditory neglectAbsent sensory perception in (L) upper limb and (L) tactile neglect in the lower limb
36 On Anosognosia, Body neglect (Hemisomatognosia) and somatoparaphrenia Anosognosia – our patient has itBody neglect by Bisiach’s test – our patient does not have itSomatoparaphrenia – our patient has it
39 On Allesthesia, tactile neglect and ‘blind touch’ ‘Touch your left arm’ Bisiach’s test of body neglect.Absent proprioception and touch in the left upper limbPatient is still able to touch her left arm whatever position the examiner keeps the arm in.