Makindo Medical Notes

Deep brain stimulation (DBS) primarily treats levodopa (LD)-responsive symptoms and offers sustained benefits for several years. It is a widely accepted surgical intervention for movement disorders and other neurological conditions.

About

• Surgical treatment of Parkinson's disease (PD) dates back to the 1940s, focusing initially on ablative procedures targeting the thalamus and globus pallidus pars interna (GPi).
• The popularity of these procedures waned with the introduction of levodopa but resurged in the 1990s.
• DBS replaced ablative techniques in the late 1990s due to concerns about adverse effects from bilateral lesions and irreversible outcomes from poorly placed lesions.
• The subthalamic nucleus (STN) emerged as an effective DBS target and remains the most common site for electrode placement.
• DBS is the preferred surgical treatment for patients with significant motor complications that do not respond to optimized medical therapy.

Indications

• Parkinson's Disease (PD):
  • Thalamic DBS is an option for severe, disabling tremor.
  • STN or GPi DBS effectively addresses motor fluctuations and dyskinesia.
  • Medtronic DBS Therapy targets LD-responsive symptoms, including long-standing or recent-onset motor complications.
• Essential Tremor:
  • Unilateral thalamic stimulation of the ventral intermediate nucleus (VIM) helps suppress upper extremity tremor.
  • Indicated for Parkinsonian or essential tremor that significantly impairs function and does not respond to medication.
• Dystonia:
  • DBS of the GPi or STN aids in managing chronic, intractable primary dystonia, including generalized, segmental, hemidystonia, and cervical dystonia (torticollis).
  • Approved for patients aged seven years and above.
• Obsessive-Compulsive Disorder (OCD):
  • Bilateral DBS of the anterior limb of the internal capsule (AIC) serves as an adjunct to medications or an alternative to anterior capsulotomy.
  • Indicated for treatment-resistant OCD in adults who have failed at least three SSRIs.
• Epilepsy:
  • Bilateral stimulation of the anterior nucleus of the thalamus (ANT) reduces seizure frequency in individuals with partial-onset seizures refractory to three or more antiepileptic medications.
  • Indicated for patients averaging six or more seizures per month before implant, with no more than 30 days between seizures.

MRI Considerations

• Consult neurosurgeons before performing brain MRI scans to ensure safety with DBS implants.

Contraindications

• Significant cognitive or psychiatric comorbidities, as these may worsen postoperatively or reduce the effectiveness of DBS therapy.

References

• Deep Brain Stimulation for Parkinson Disease (JAMA Neurology)