Deep brain stimulation

deep brain stimulation

1. DEEP BRAIN STIMULATION By MEENAKSHY SUDEEP

2. BASAL GANGLIA ANATOMY The Basal ganglia are collection of nuclei grouped based on there interconnections Important in coordinating movement and in cognitive function work in concert with the pyramidal motor pathway

3. COMPONENTS OF BASAL GANGLIA CORPUSTRAITUM Straitum ---- caudate nucleus and putamen Pallidum ---- globus pallidus SUBSTANTIA NIGRA pars compacta Pars reticulate SUBTHALAMIC NUCLEUS AMYGDALA CLAUSTRUM

4. BASAL GANGLIA AND PATHWAYS

5. ROLE OF BASAL GANGLIA Motor and cognitive functions Controlling eye movements Role in motivation Decision making Working memory

6. CLINICAL SIGNIFICANCE Hyperkinetic and hypokinetic disorders Mainly movement disorders Common disorders associated with basalganglia dysfunctions are chorea, wilsons disease, touretts syndrome, pd , kernictures , pap syndrome etc ,.. In Parkinson disease the degeneration of dopaminergic neurons of the substantia nigra pars compacta triggers a cascade of functional changes affecting the whole basal ganglia network

7. DEEP BRAIN STIMULATION Inroduced in the 1990s By Benavides ET AL neurosurgical procedure involving the implantation of a medical device called a neurostimulator sends electrical impulses, through implanted electrodes, to specific targets in the brain (brain nuclei) for the treatment of movement and neuropsychiatric disorders

8. MECHANISM OF DBS Proposed mechanism of DBS can be grouped into 4 main catagories INHIBITION OF TARGET ACTIVATION OF TARGET COMBINED INHIBITION AND ACTIVATION DISRUPTION OF PATHOLOGICAL OSCILLATION TO RESTORE RHYTHMIC ACTIVITY AND SYNCHRONISATION It involves decoupling of axonal and neuronal transport in bg that takes place in corticospinopallidothalamic tract

9. DBS-probes shown in X-ray of the skull

10. Components of DBS The LEAD or electrode : a thin, insulated wire—is inserted through a small opening in the skull and implanted in the brain. The tip of the electrode is positioned within the targeted brain area The EXTENSION : Is an insulated wire that is passed under the skin of the head, neck, and shoulder, connecting the lead to the neuro stimulator The NEUROSTIMULTOR : is the third component and is usually implanted under the skin near the collarbone

11. TARGET SITES FOR STIMULATION SUBTHALAMIC NUCLEUS GLOBUS PALLIDUS INTERNA THALAMUS

12. PATIENT SELECTION FOR DBS The best candidates for DBS therapy will meet most of the following criteria: Patient have PD symptoms for 5 years On/off fluctuations with or without dyskinesia If pd symptoms interfere with daily activities continue to have a good response to PD medications, especially carbidopa/ levodopa

13. TECHNIQUE OF DBS The procedure is used only for patients whose symptoms cannot be adequately controlled with medication Surgical implanatation Targeted area is located by ct or mri imaging Quadripolar leads are connected to stimulator and to battery Once electrodes are implanted it is attached top wires that run inside body from head down to collar bone where battery operated stimulator are implanted From stimulator electrical impulses are continuously delivered over wire to electrode in brain Reprograming can be done with 3,4 months

14. DBS SURGERY

15. POST SURGERY PATIENT CARE Complications can develop during the first few weeks or even months after surgery. Patient should be aware the signs and symptoms of infection precautions that you can take to prevent an infection include the following Never scratch, touch, or put any pressure on the incision Be sure pillows, sheets, and bedding are clean Keep the stitches clean and dry Return to have sutures or staples removed at the schedule time Look for sign of infection

16. SIDE EFFECTS and RISK Headache, nausea and vomiting Pain, inflammation and swelling at surgical site Confusion Numbness and weakness of body Difficulty in speech Mood changes Bleeding in brain Movement disorders etc …

17. COMPLICATION OF DBS SURGERY Hardware related complications Lead migration Lead fracture Lead erosion Lead malfunction Malfunctioning of neurostimulator Seizures Dystonis Hemorraghe etc ….

18. ADVANTAGE OF DBS IN PARKINSON DISEASE DBS is not a cure for PD It is a treatment that helps relieve the motor symptoms of PD, as well as some of the non-motor symptoms It is called a symptomatic therapy Bilateral DBS is often required to improve gait, although sometimes unilateral DBS has a marked effect on walking Smooths out on/off fluctuations Improves tremor, stiffness (rigidity), bradykinesia, and dyskinesia Decreases medications

19. DBS site Effect of therapy Thalamus (Vim) Reduces tremor but not the other of PD Globus pallidus ( GPi ): Reduces tremor, rigidity, bradykinesia, gait problems, dyskinesia Subthalamic nucleus ( STN): Reduces tremor, rigidity, bradykinesia, gait problems, dyskinesia

20. INDICATION OF DBS Parkinson disease Essential tremor Dystonia Epilepsy Tournette syndrome Ocd Chronic pain

21. Advantages of DBS Reversibility Adjustability imp[rove quality of life Help to reduce medications Relatively safe procedure Improves energy level

22. Disadavantages Highly expensive Increased risk of infection due to implantation of foreign object

23. Bibliography Guide_to_DBS_Stimulation_Therapy Parkinson.org