Abhängigkeitserkrankungen im Kontext der Tiefen Hirnstimulation – eine literaturgestützte systematische Auswertung

Improved Function After Deep Brain Stimulation for Chronic, Severe Traumatic Brain Injury

BACKGROUND

Severe traumatic brain injury (TBI) damages the frontal lobes and connecting networks, which impairs executive functions, including the ability to self-regulate. Despite significant disabling effects, there are few treatment options in the chronic phase after injury.

OBJECTIVE

To investigate the safety and potential effectiveness of deep brain stimulation (DBS) for individuals with chronic, disabling TBI and problems of behavioral and emotional self-regulation.

METHODS

This study was an open-label, prospective design with serial assessments of behavioral outcomes and positron emission tomography 2 years after DBS implantation. Four participants 6 to 21 years after severe TBIs from automobile crashes were included. Although alert and volitional, all experienced significant executive impairments, including either impulsivity or reduced initiation. DBS implants were placed bilaterally in the nucleus accumbens and anterior limb of the internal capsule to modulate the prefrontal cortex.

RESULTS

The procedure was safe, and all participants had improved functional outcomes. Two years after implantation, 3 met a priori criteria for improvement on the Mayo-Portland Adaptability Inventory-4. Improvement was due largely to better emotional adjustment, although 1 participant showed marked increases in multiple domains. Significant improvement in a composite score of functional capacity indicated improved independence in self-care and activities of daily living. The pattern of change in cognition corresponded with changes in activation of the prefrontal cortex observed in serial scanning.

CONCLUSION

This first study of DBS to this target for severe TBI supports its safety and suggests potential effectiveness to improve function years after injury. The primary impact was on behavioral and emotional adjustment, which in turn improved functional independence.

ABBREVIATIONS

DBS, deep brain stimulationIC, internal capsuleMPAI-4, Mayo-Portland Adaptability Inventory-4NAcc, nucleus accumbensTBI, traumatic brain injury.

Neurostimulation techniques in the treatment of nicotine dependence: A review

OBJECTIVE

Nicotine dependence accounts for significant mortality, morbidity, and socio-economic burdens. It remains a significant public health concern since it is among the leading causes of mortality worldwide and of preventable deaths in developed countries. Despite the availability of approved medications to treat nicotine dependence, along with cognitive behavioral therapy, only 6% of the total number of smokers who report wanting to quit each year are successful in doing so for more than a month mostly with poor abstinence rates. Urgent therapeutic alternatives are therefore needed such as neurostimulation techniques. The purpose of this review is to describe studies that have evaluated the safety and efficacy of these techniques for the treatment of nicotine dependence.

METHODS

The electronic literature on repetitive transcranial magnetic stimulation, theta-burst stimulation, deep transcranial magnetic stimulation, transcranial direct current stimulation, magnetic seizure therapy, electroconvulsive therapy, cranial electro-stimulation, and deep brain stimulation in the treatment of nicotine addiction were reviewed.

RESULTS

Most of these studies found that some of these neurostimulation techniques are safe and potentially effective in the reduction of craving to nicotine as well as in the reduction of cigarette consumption.

CONCLUSION AND SCIENTIFIC SIGNIFICANCE

Given the promising results of some of the studies particularly with repetitive transcranial magnetic stimulation, theta-burst stimulation, transcranial direct current stimulation and, possibly, deep transcranial magnetic stimulation, future controlled studies with larger samples, and optimal stimulus parameters should be designed to confirm these findings. (Am J Addict 2016;25:436-451).

Targeting the affective and cognitive aspects of chronic neuropathic pain using basal forebrain neuromodulation: rationale, review and proposal

Chronic pain is a major health problem in developed countries where it may affect as much as 20% of the adult population. There have been no significant clinical breakthroughs in therapeutic options for persons with chronic neuropathic pain. These limitations underscore the importance of developing new therapies for this disabling pain syndrome. We have reviewed the limitations of the present treatment strategies for chronic pain, neurophysiology of somatosensory transmission and nociception, mechanisms of neuropathic pain, the concept of a "pain matrix" and the "top-down" modulation of pain, and the cognitive affective role in processing of the pain experience. We found that affective and cognitive aspects of pain constitute important considerations in achieving improvements in the outcomes of pain neuromodulation in patients with chronic neuropathic pain. Based on our review, we propose that future novel neuromodulatory therapeutic strategies should be directed at areas in the brain that are involved in the neural mechanisms of reward valuation and appetitive motivation such as nucleus accumbens, ventral tegmental area, and prefrontal cortex.

Deep brain stimulation for psychiatric disorders

BACKGROUND

Deep brain stimulation (DBS), an established treatment for some movement disorders, is now being used experimentally to treat psychiatric disorders as well. In a number of recently published case series, DBS yielded an impressive therapeutic benefit in patients with medically intractable psychiatric diseases.

METHODS

This review of the use of DBS to treat psychiatric disorders is based on literature retrieved from a selective Pubmed search for relevant keywords, reference works on the topic, and the authors' own research.

RESULTS

Studies have been performed on the use of DBS to treat medically intractable obsessive-compulsive disorder, depressive disorders, and Tourette syndrome. The case numbers in the cited publications were small, yet at least some of them involved a methodologically sound investigation. Thus, in some studies, the strength of the effect was controlled with a double-blinded interval in which the stimulation was turned off. In general, the primary symptoms were found to improve markedly, by 35% to 70%, although not all patients responded to the treatment. Adverse effects of DBS were very rare in most studies and could usually be reversed by changing the stimulation parameters.

CONCLUSIONS

The results of DBS for psychiatric disorders that have been published to date are encouraging. They open up a new perspective in the treatment of otherwise intractable disorders. Nonetheless, the efficacy, mechanism of action, and adverse effects of DBS for this indication still need to be further studied in methodologically adequate trials that meet the highest ethical standard.