Deep brain stimulation for pain relief: a meta-analysis

Deep brain stimulation (DBS) has been used to treat intractable pain for over 50 years. Variations in targets and surgical technique complicate the interpretation of many studies. To better understand its efficacy, we performed a meta-analysis of DBS for pain relief. MEDLINE (1966 to February 2003) and EMBASE (1980 to January 2003) databases were searched using key words deep brain stimulation, sensory thalamus, periventricular gray and pain. Inclusion criteria were based on patient characteristics and protocol clarity. Six studies (between 1977–1997) fitting the criteria were identified. Stimulation sites included the periventricular/periaqueductal grey matter (PVG/PAG), internal capsule (IC), and sensory thalamus (ST). The long-term pain alleviation rate was highest with DBS of the PVG/PAG (79%), or the PVG/PAG plus sensory thalamus/internal capsule (87%). Stimulation of the sensory thalamus alone was less effective (58% long-term success) (p < 0.05). DBS was more effective for nociceptive than deafferentation pain (63% vs 47% long-term success; p < 0.01). Long-term success was attained in over 80% of patients with intractable low back pain (failed back surgery) following successful trial stimulation. Trial stimulation was successful in approximately 50% of those with post-stroke pain, and 58% of patients permanently implanted achieved ongoing pain relief. Higher rates of success were seen with phantom limb pain and neuropathies. We conclude that DBS is frequently effective when used in well-selected patients. Neuroimaging and neuromodulation technology advances complicate the application of these results to modern practice. Ongoing investigations should shed further light on this complex clinical conundrum

Deep brain stimulation: a new treatment for hypertension?

We report a 61-year-old hypertensive man who underwent deep brain stimulation of the periventricular/periaqueductal grey area for the relief of chronic neuropathic pain affecting his oral cavity and soft palate. During intraoperative stimulation, we were able to modulate his blood pressure up or down, depending on electrode location. This is the first evidence that hypertension could be effectively treated with electrical stimulation of the midbrain

Deep brain stimulation: a new treatment for hypertension?

We report a 61-year-old hypertensive man who underwent deep brain stimulation of the periventricular/periaqueductal grey area for the relief of chronic neuropathic pain affecting his oral cavity and soft palate. During intraoperative stimulation, we were able to modulate his blood pressure up or down, depending on electrode location. This is the first evidence that hypertension could be effectively treated with electrical stimulation of the midbrain

Deep brain stimulation for generalised dystonia and spasmodic torticollis

Dystonia appears distinct from the other tremulous disorders in that improvement following deep brain stimulation frequently appears in a delayed and progressive manner. The rate of this improvement and the point at which no further progress can be expected are presently unknown. The establishment of these parameters is important in the provision of accurate and relevant prognostic information to these patients, their carers, and their treating physicians. We studied 12 consecutive patients with generalised dystonia (n = 6) and spasmodic torticollis (n = 6) who underwent bilateral globus pallidus internus (GPi) deep brain stimulation (DBS) and were followed up for a minimum of 2 years postoperatively. Standard rating scales were used to quantify their neurological improvement. Both groups experienced a statistically significant improvement in their rating scores at both one and two years following surgery. At 2 years follow-up, the spasmodic torticollis group exhibited a 59% improvement in their total Toronto Western Spasmodic Torticoilis Rating Scale (TWSTRS) rating score and the generalised dystonia group attained a 46% improvement in their overall Burke, Fahn and Marsden Dystonia Rating Scale (BFMDRS) evaluation. Ninety-five percent of the final improvement was attained by 6.4 months in the generalised dystonia group and by 6.6 months in those with spasmodic torticollis. There was no significant improvement after one year postoperatively. These findings add further support to GPi DBS as an effective treatment for generalised dystonia and spasmodic torticollis, and furnish important information as to the expected rate of improvement and the point at which no further gains can be reasonably anticipated