Directional electrodes in deep brain stimulation: Results of a survey by the European Association of Neurosurgical Societies (EANS).

Introduction: Directional Leads (dLeads) represent a new technical tool in Deep Brain Stimulation (DBS), and a rapidly growing population of patients receive dLeads. Research question: The European Association of Neurosurgical Societies(EANS) functional neurosurgery Task Force on dLeads conducted a survey of DBS specialists in Europe to evaluate their use, applications, advantages, and disadvantages. Material and methods: EANS functional neurosurgery and European Society for Stereotactic and Functional Neurosurgery (ESSFN) members were asked to complete an online survey with 50 multiple-choice and open questions on their use of dLeads in clinical practice. Results: Forty-nine respondents from 16 countries participated in the survey (n = 38 neurosurgeons, n = 8 neurologists, n = 3 DBS nurses). Five had not used dLeads. All users reported that dLeads provided an advantage (n = 23 minor, n = 21 major). Most surgeons (n = 35) stated that trajectory planning does not differ when implanting dLeads or conventional leads. Most respondents selected dLeads for the ability to optimize stimulation parameters (n = 41). However, the majority (n = 24), regarded time-consuming programming as the main disadvantage of this technology. Innovations that were highly valued by most participants included full 3T MRI compatibility, remote programming, and closed loop technology. Discussion and conclusion: Directional leads are widely used by European DBS specialists. Despite challenges with programming time, users report that dLeads have had a positive impact and maintain an optimistic view of future technological advances.

[The new Parkinson's disease pain classification system (PD-PCS)]. / Die neue Parkinson-Schmerzklassifikation (PSK).

BACKGROUND: Chronic pain is a common non-motor symptom in patients with Parkinson's disease (PD). AIM: To facilitate the diagnosis of pain in PD, we developed a new classification system the Parkinson's disease pain classification system (PD-PCS) and translated the corresponding validated questionnaire into German. METHODS: A causal relationship of the respective pain syndrome with PD can be determined by four questions before assigning it hierarchically into one of three pain categories (neuropathic, nociceptive and nociplastic). RESULTS: In the initial validation study 77% of the patients (122/159) had PD-associated pain comprising 87 (55%) with nociceptive, 36 (22%) with nociplastic and 24 (16%) with neuropathic pain. The study revealed a high validity of the questionnaire and a moderate intrarater and interrater reliability. The questionnaire has been adapted into German and employed in 30 patients. DISCUSSION: The PD-PCS questionnaire is a valid and reliable tool to determine the relationship of a pain syndrome with PD before classifying it according to the underlying category, facilitating further diagnostics and treatment.

Determining the Orientation of Directional Deep Brain Stimulation Electrodes Using 3D Rotational Fluoroscopy.

BACKGROUND AND PURPOSE: New deep brain stimulation leads with electrode contacts that are split along their circumference allow steering of the electrical field in a predefined direction. However, imaging-assisted directional stimulation requires detailed knowledge of the exact orientation of the electrode array. The purpose of this study was to evaluate whether this information can be obtained by rotational 3D fluoroscopy. MATERIALS AND METHODS: Two directional leads were inserted into a 3D-printed plaster skull filled with gelatin. The torsion of the lead tip versus the lead at the burr-hole level was investigated. Then, 3 blinded raters evaluated 12 3D fluoroscopies with random lead orientations. They determined the lead orientation considering the x-ray marker only and considering the overlap of the gaps between the contact segments. Intraclass correlation coefficients and an extended version of the Bland-Altman plot were used to determine interrater reliability and agreement of the measurements of the different raters. RESULTS: Electrode torsion of up to 35° could be demonstrated. Evaluation of the lead rotation considering the x-ray marker only revealed limits of agreement of ±9.37° and an intraclass correlation coefficient of 0.9975. In addition, taking into account the lines resulting from overlapping of the gaps between the electrode segments, the limits of agreement to the mean were ±2.44° and an intraclass correlation coefficient of 0.9998. CONCLUSIONS: In directional deep brain stimulation systems, rotational 3D fluoroscopy combined with the described evaluation method allows for determining the exact orientation of the leads, enabling the full potential of imaging-assisted personalized programming.

First experience using navigation-guided radiofrequency kyphoplasty for sacroplasty in sacral insufficiency fractures.

PURPOSE: To evaluate the efficacy and safety of navigation-guided radiofrequency kyphoplasty for sacroplasty in patients with sacral insufficiency fractures. METHODS: In this single-center retrospective observational study, four consecutive patients with sacral insufficiency fractures were treated with navigation-guided radiofrequency kyphoplasty for sacroplasty between April 2010 and May 2012. Symptom characteristics, pain duration and pain intensity were recorded for each patient. Cement extravasation was evaluated in thin-sliced and triplanar reconstructed CT scans of the sacrum. RESULTS: Four female patients with painful sacral insufficiency fractures and extensive osteopenic areas significantly improved from an average pre-treatment VAS score of 8.3 ± 0.5 to 2.3 ± 1.0 (p < 0.001) on the first postoperative day and to 1.3 ± 1.9 (p < 0.004) at follow-up (mean, 20.1 weeks). Slight cement extravasations were observed without evidence of being symptomatic. No major complications or procedure-related morbidity were noted. CONCLUSION: From the limited experience in four patients, navigation-guided radiofrequency kyphoplasty appears to be a safe and effective treatment option for sacral insufficiency fractures even though asymptomatic cement extravasation was noted. The use of navigation based on intraoperative 3 D images simplifies the positioning of the navigated bone needles via the long axis approach. The radiofrequency kyphoplasty system provides the possibility to administer a sufficient amount of bone cement with a well-defined viscosity over the entire period of the procedure leading to high security and low cement extravasation. Sacroplasty provides rapid and enduring pain relief and facilitates prompt mobilization.