Abstract
ObjectivePrevious studies showed that deep brain stimulation (DBS) relieves pain symptoms in Parkinson disease (PD) patients when programmed for motor-symptom relief. One factor involved in pain processing is sensory perception of stimuli. With the advent of directional leads, we explore whether directional DBS affects quantitative sensory testing (QST) metrics acutely.MethodsPD patients with subthalamic (STN) DBS and directional leads were tested in 5 settings (DBS-OFF, DBS-ON with omnidirectional stimulation, and DBS-ON) for each of three directional segments of contact used for clinical programming. The Unified Parkinson’s Disease Rating Scale (UPDRS-III) assessed patient’s motor skills at time of study visit at clinical contact and at contact which produced optimal sensory threshold (defined by the greatest tolerance to mechanical stimuli). Correlation analyses were performed between stimulation parameters [amplitude, frequency, pulse width (PW), total electrical energy delivered (TEED)] and outcome metrics.ResultsSensory thresholds were obtained in nine patients. Directional stimulation did not significantly alter patient perceptions of sensory stimulus [cold pain (p = 0.69), warm pain (p = 0.99), Von frey fibers (p = 0.09), pin-prick (p = 0.88), vibration (p = 0.40), pressure (p = 0.98)]. With correlation analysis, increasing PW at the posterior contact increased pin prick and vibration sensitivity (p < 0.001). Additionally, an increase in TEED caused a decrease in sensitivity to warm detection when using the anterior (p = 0.04), lateral (p = 0.02), and medial contacts (p = 0.03), and also caused a decrease in sensitivity to cold detection when using the medial contact (p = 0.03). UPDRS-III remained stable during testing.ConclusionMotor benefit can be acutely maintained at directional contacts, whereas directional stimulation can modulate thermal and mechanical sensitivity. Further investigation will determine whether these changes are maintained chronically or can be improved with optimized programming.
Highlights
Parkinson’s disease (PD) is a debilitating neurodegenerative disorder that affects over 10 million people worldwide Parkinsons Foundation (2019
Preliminary research of sensory thresholds noted that thermal perception was worse in PD patients not receiving stimulation as compared to healthy controls, and found that this thermal perception improved in PD patients once stimulation was turned on (Maruo et al, 2011)
In PD patients experiencing chronic pain, low frequency stimulation (LFS) was found to produce lower heat thresholds compared to both high frequency stimulation (HFS) and no stimulation (Belasen et al, 2017)
Summary
Parkinson’s disease (PD) is a debilitating neurodegenerative disorder that affects over 10 million people worldwide Parkinsons Foundation (2019). When patients become refractory to medical management, deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a wellestablished neuromodulatory treatment shown to improve the motor symptoms of PD (Limousin et al, 1998). This treatment may improve non-motor symptoms in PD patients Pain is on such symptom and in pre-clinical studies, quantitative sensory testing (QST) is a method of measuring sensory thresholds that may be used as a surrogate. These indications show potential for the use of DBS to modulate sensory disturbances in PD patients
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
