Deep brain stimulation in treatment of patients with advanced Parkinson's disease

Abstract

Parkinsonova bolest (PB) je kronična progresivna neurodegenerativna bolest koja se javlja većinom u starijih osoba. Smatra se da je rezultat interakcije genetskih i okolišnih čimbenika. Za shvaćanje hipokinetičkog poremećaja pokreta kao što je PB, važno je razumijeti neuroanatomiju petlji bazalnih ganglija jer poremećaj u njihovoj organizaciji i funkcioniranju dovodi do manifestacije poremećaja. PB ima motoričke te nemotoričke manifestacije. Četiri motorička znaka karakteristična za PB su tremor, rigiditet, bradikinezija te posturalna nestabilnost. Od nemotoričkih znakova ističu se kognitivni poremećaji, psihičke smetnje te smetnje spavanja i autonomnog sustava. Tijekom 1950-ih i 1960-ih godina glavna metoda terapije bile su ablacijske kirurške tehnike poput talamotomije i palidotomije. Pojavom lijeka levodope (L-dopa) 1967. godine, ablacijske kirurške tehnike zamijenjene su farmakološkom terapijom. No povišenjem doze L-dope dolazi do pojave teških motoričkih nuspojava, takozvanih diskinezija. 1987. godine se prvi put koristi nova kirurška tehnika, duboka mozgovna stimulacija (DBS). To je tehnika električne stimulacije dubokih struktura mozga koja je danas skoro u potpunosti zamijenila ablacijske kirurške tehnike zbog svoje reverzibilnosti, manje invazivnosti te manjeg broja komplikacija. Uveli su je Alim Louis Benabid i Pierre Pollak za liječenje tremora, stimulacijom talamusa, a 1993. godine su stimulirali subtalamičku jezgru kod pacijenta sa teškim oblikom PB-a. Osim na motoričke znakove, djeluje i na diskinezije inducirane L-dopom. Uz sve prednosti, kao i kod svake kirurške tehnike javljaju se određeni rizici od komplikacija. No unatoč rizicima, DBS danas ostaje glavnom neurokirurškom terapijom u liječenju PB-a kod ispravno indiciranih pacijenata.Parkinson’s disease is a chronic progressive neurodegenerative disease that mainly occurs in older people. It is thought to be a result of interaction of both genetic and environmental factors. To understand hypokinetic movement disorder such as Parkinson’s disease, it is important to know neuroanatomy of basal ganglia circuits, because disturbance in its organization and functioning leads to manifestation of the said disorder. Parkinson’s disease has both motor and non-motor manifestations. Four cardinal motor signs are tremor, rigidity, bradykinesia and postural instability. Non-motor signs that stand out are cognitive disorders, pshychiatric disorders, sleep disturbances and disturbances of the autonomic system. During 1950s and 1960 the main methods of therapy were ablative surgical techniques, such as thalamotomy and pallidotomy. With appearance of levodopa (L-dopa) in 1967, ablative surgical techniques were largely replaced by pharmacological treatment. But by increasing the dose of L-dopa, motor side effects, such as dyskinesia occured. In 1987 new surgical technique was developed - deep brain stimulation (DBS). It is a technique of electrical stimulation of deeper parts of the brain which has almost entirely replaced ablative surgical techniques because of its reversibility, lesser invasiveness and less number of complications. It was developed by Alim Louis Benabid and Pierre Pollak for treating tremor by stimulating thalamus. In 1993 they stimulated subthalamic nucleus in patients with advanced Parkinson’s. It worked on both motor symptoms and L-dopa induced dyskinesias. Even though DBS has many advantages, there are also certain risks of complications. But nevertheless, DBS is today the main neurosurgical therapy in treating Parkinson’s disease in correctly chosen patients