Effects of Deep-Brain Stimulation on Speech: Perceptual and Acoustic Data

PURPOSE

This study examined speech changes induced by deep-brain stimulation (DBS) in speakers with Parkinson's disease (PD) using a set of auditory-perceptual and acoustic measures.

METHOD

Speech recordings from nine speakers with PD and DBS were compared between DBS-On and DBS-Off conditions using auditory-perceptual and acoustic analyses. Auditory-perceptual ratings included voice quality, articulation precision, prosody, speech intelligibility, and listening effort obtained from 44 listeners. Acoustic measures were made for voicing proportion, second formant frequency slope, vowel dispersion, articulation rate, and range of fundamental frequency and intensity.

RESULTS

No significant changes were found between DBS-On and DBS-Off for the five perceptual ratings. Four of six acoustic measures revealed significant differences between the two conditions. While articulation rate and acoustic vowel dispersion increased, voicing proportion and intensity range decreased from the DBS-Off to DBS-On condition. However, a visual examination of the data indicated that the statistical significance was mostly driven by a small number of participants, while the majority did not show a consistent pattern of such changes.

CONCLUSIONS

Our data, in general, indicate no-to-minimal changes in speech production ensued from DBS stimulation. The findings are discussed with a focus on large interspeaker variability in PD in terms of their speech characteristics and the potential effects of DBS on speech.

Accessibility of Device-Aided Therapies for Persons With Parkinson's Disease in Poland

OBJECTIVE

Access to care for people with Parkinson's disease (PD), particularly to device-aided therapies (DAT), is not equally distributed. The objective was to analyze accessibility to DAT (deep brain stimulation, intraduodenal levodopa pump therapy, and apomorphine pump therapy) in Poland.

METHODS

We analyzed the distribution of DAT use in Poland by determining the number of persons with PD receiving one of the three DATs during 2015-2021.

RESULTS

In 2021, the number of persons receiving DAT in Poland was 0.56% of the total PD population, increasing from 0.21% in 2015. Overall, deep brain stimulation was the preferred DAT in Poland, but strong regional differences in the use of the other DATs were observed. Accessibility to DAT was negatively associated with average annual income (p < 0.001).

CONCLUSION

Access to DAT for persons with PD in Poland is still limited, and strong regional differences in accessibility were observed, although its general increase over the last decade is encouraging.

[Problems in organizing neurosurgical care for patients with Parkinson's disease in the Russian Federation]

BACKGROUND

Currently, there are some problems in the Russian Federation complicating development of neurosurgical care for patients with Parkinson's disease (PD).

MATERIAL AND METHODS

In 2022, neurologists - movement disorders specialists were surveyed to analyze situation with PD pharmacological treatment and referral of patients for surgical treatment in Russian constituent entities. Data on neurosurgical treatment of PD were obtained by collecting information on the surgical activity of medical institutions in the Russian Federation. Most hospitals involved in PD treatment took part in this study.

RESULTS

The state of neurosurgical care for patients with PD is analyzed and possible ways to improve the quality of treatment are discussed.

CONCLUSION

Over the past 20 years, a system of neurosurgical care for patients with PD has been formed in 14 centers in the Russian Federation (2022). Obstacles to its further development can be divided into 3 categories: problems of patient selection and routing, complexity of organization and financing surgeries, and imperfect postoperative patient management. Ways to overcome these obstacles imply expanding the network of centers for extrapyramidal diseases, development of domestic neurostimulation systems, improving the distribution of quotas taking into account the capabilities of hospitals, specialized training of neurologists for extrapyramidal centers and neurosurgeons for deep brain stimulation centers, adequate financing and systematization of postoperative management of patients with PD.

Periosteal Turnover Flap for Coverage and Salvage of Exposed Deep Brain Stimulation Device

Implanted deep brain stimulation (DBS) devices are crucial in the treatment of movement disorders. Hardware extrusion is among the most frequent complications of the implantation process and requires reconstruction with well-vascularized tissues. The authors present a case of periosteal turnover flap for coverage of an exposed DBS device. An 11-year-old female patient with spastic cerebral palsy presented with an exposed DBS device located in the right parietal area. The exposed device was covered by a proximally based periosteal flap. Postoperative evaluations at months 1, 2, 3, and 8 revealed no signs of infection or dehiscence. This brief clinical study shows that reconstruction with periosteal turnover flaps is both an easy and excellent choice for secondary closure of exposed DBS devices.

Canadian Assessment of Deep Brain Stimulation Access: The Canada Study

BACKGROUND

The Canada Health Act requires reasonable access to all medically necessary therapies. No information is available to assess the current access to neuromodulation across Canada. This study quantifies the current rate of deep brain stimulation (DBS) for the entire country of Canada. Analyses were performed to determine whether there were differences in access based on provincial or territorial location, rural or non-rural region, or socioeconomic status.

METHODS

All implanted DBS devices in Canada over a 2-year epoch (January 2015 to December 2016) were supplied by either Boston Scientific or Medtronic. Investigators received anonymized data from these companies, including patient age and home residence region. The 2016 Statistics Canada census data were used to determine the rate of DBS surgery and whether access was related to provincial location, rural versus non-rural region or socioeconomic status.

RESULTS

A total of 722 patients were studied. The rate of DBS surgery for the entire country was ten per million population per year. Saskatchewan was significantly above (374%) the national average, whereas Quebec (40%) and Newfoundland & Labrador (32%) were significantly below the national average. No patients from the three territories received DBS. There were no significant differences in access from rural versus non-rural areas or in regions within provinces with different socioeconomic status.

CONCLUSIONS

This is the first study to quantify all patients receiving DBS within an entire country. The current rate of DBS surgery within Canada is ten cases per million per year. Statistically significant regional differences were discovered and discussed.

Evaluation of Patient Perspectives Toward Awake, Frame-Based Deep-Brain Stimulation Surgery

BACKGROUND

Deep brain stimulation (DBS) is an effective therapeutic modality; however, only a percentage of eligible patients undergo the procedure.

OBJECTIVES

To study patients' perspectives toward DBS surgery.

METHODS

A survey was sent to 95 consecutive adult patients who underwent DBS surgery for Parkinson disease, essential tremor, or dystonia; the response rate was 73% (69 patients). Post-hoc analyses were performed to evaluate factors that led to favorable outcomes. The average time between surgical procedure to survey completion was 16 months.

RESULTS

Awake surgery, use of a rigid head frame, and having hair clipped were seldom reported as major deterrents to surgery. Patients retrospectively reported an average comfort level of 8.3 ± 1.8 during surgery. The average comfort level with head frame placement was reported as 5.2 ± 3.15, and patients reporting discomfort with the frame nonetheless reported overall comfort with the procedure (8.7 ± 1.8). An analysis of satisfaction revealed that 90% of patients would recommend the procedure to a family member or friend and that 78% of patients would undergo the procedure again. A post-hoc analysis of patients who were not satisfied with the procedure revealed that this subset reported significantly less overall comfort (6.9 ± 1.7, P = 0.0003) and were less likely to report that the goals and expectations of surgery were clearly discussed before surgery (P = 0.0004).

CONCLUSIONS

Frame placement, awake surgery, and head shaving did not appear to play a significant role in most patients' decision-making process to undergo DBS, as analyzed in this retrospective cohort. The majority of patients were satisfied with the procedure and reported being comfortable. Managing goals and expectations preoperatively played a significant role in ultimate overall satisfaction.

The Current Status of Deep Brain Stimulation for the Treatment of Parkinson Disease in the Republic of Korea

Parkinson disease (PD) is a common neurodegenerative disease with an increasing prevalence in Korea. Deep brain stimulation (DBS) is a safe and effective surgical treatment option for this disease. The aim of this review was to provide an update regarding current DBS practices with respect to the treatment of PD in the Republic of Korea. The first DBS in Korea was performed in 2000; approximately 2,000 patients have undergone DBS for a variety of neurological disorders, the majority of whom were patients with PD. Approximately 150 new patients with PD receive DBS annually, and more than 20 centers perform DBS. However, DBS remains underutilized for many reasons, and the clinical case burden at many institutions is below the level presumed adequate for qualified practice. With a rapidly aging population and an evolving socioeconomic environment, the need for surgical intervention for PD is likely to increase significantly in the future. Many issues such as finances, education, and quality assurance must be resolved to cope with this need.

Estimating the Proportion of Essential Tremor and Parkinson's Disease Patients Undergoing Deep Brain Stimulation Surgery: Five-Year Data From Columbia University Medical Center (2009-2014)

OBJECTIVE

The aim of this study was to estimate, at a tertiary referral center, the proportion of essential tremor (ET) and Parkinson's disease (PD) patients who underwent DBS surgery.

BACKGROUND

DBS surgery is an important treatment for ET and PD. Surprisingly, there are no published data on the precise proportion of such patients who are referred for this procedure.

METHODS

Using the computerized billing database at the Center for Parkinson's Disease and Other Movement Disorders, Columbia University Medical Center, we searched for patients who received the diagnostic codes 333.1 (tremor) and 332.0 (PD) and who were followed by a doctor at the center during the 5-year period from 2009 to 2014. The number of patients who underwent DBS surgery for these diagnoses during this time period was also determined.

RESULTS

Seventy-seven patients with these diagnoses (52 PD, 14 ET, and 11 ET + PD) who were followed at the center underwent DBS surgery during this time period. The proportion of ET patients who underwent DBS surgery was 2.90% (95% confidence interval [CI]: 1.78-4.02), and for PD this was 1.38% (95% CI: 1.04-1.72). The difference was significant (P < 0.001).

CONCLUSIONS

At a tertiary-referral center, 1 in 34 ET patients and 1 in 72 PD patients underwent DBS surgery. Similar studies from other major centers would be of additional value. These data are likely to have utility when planning health care services for patients with these diagnoses.

Predictors of unfavorable outcomes following deep brain stimulation for movement disorders and the effect of hospital case volume on outcomes: an analysis of 33, 642 patients across 234 US hospitals using the National (Nationwide) Inpatient Sample from 2002 to 2011

OBJECT

With limited data available on association of risk factors and effect of hospital case volume on outcomes following deep brain stimulation (DBS), the authors attempted to identify these associations using a large population-based database.

METHODS

The authors performed a retrospective cohort study involving patients who underwent DBS for 3 primary movement disorders: Parkinson’s disease, essential tremor, and dystonia from 2002 to 2011 using the National (Nationwide) Inpatient Sample (NIS) database. Using national estimates, the authors identified associations of patient demographics, clinical characteristics, and hospital characteristics on short-term postoperative outcomes following DBS. Additionally, effect of hospital volume on unfavorable outcomes was investigated.

RESULTS

Overall, 33, 642 patients underwent DBS for 3 primary movement disorders across 234 hospitals in the US. The mean age of the cohort was 63.42 ± 11.31 years and 36% of patients were female. The inpatients’ postoperative risks were 5.9% for unfavorable discharge, 10.2% for prolonged length of stay, 14.6% for high-end hospital charges, 0.5% for wound complications, 0.4% for cardiac complications, 1.8% for venous thromboembolism, and 5.5% for neurological complications, including those arising from an implanted nervous system device. Compared with low-volume centers, odds of having an unfavorable discharge, prolonged LOS, high-end hospital charges, wound, and cardiac complications were significantly lower in the high-volume and medium-volume centers.

CONCLUSIONS

The authors’ study provides individualized estimates of the risks of postoperative complications based on patient demographics and comorbidities and hospital characteristics, which could potentially be used as an adjunct for risk stratification for patients undergoing DBS.

Regional trends and the impact of various patient and hospital factors on outcomes and costs of hospitalization between academic and nonacademic centers after deep brain stimulation surgery for Parkinson's disease: a United States Nationwide Inpatient Sample analysis from 2006 to 2010

Object

The aim of this study was to analyze the incidence of adverse outcomes, complications, inpatient mortality, length of hospital stay, and the factors affecting them between academic and nonacademic centers after deep brain stimulation (DBS) surgery for Parkinson's disease (PD). The authors also analyzed the impact of various factors on the total hospitalization charges after this procedure.

Methods

This is a retrospective cohort study using the Nationwide Inpatient Sample (NIS) from 2006 to 2010. Various patient and hospital variables were analyzed from the database. The adverse discharge disposition and the higher cost of hospitalization were taken as the dependent variables.

Results

A total of 2244 patients who underwent surgical treatment for PD were identified from the database. The mean age was 64.22 ± 9.8 years and 68.7% (n = 1523) of the patients were male. The majority of the patients was discharged to home or self-care (87.9%, n = 1972). The majority of the procedures was performed at high-volume centers (64.8%, n = 1453), at academic institutions (85.33%, n = 1915), in urban areas (n = 2158, 96.16%), and at hospitals with a large bedsize (86.6%, n = 1907) in the West or South. Adverse discharge disposition was more likely in elderly patients (OR > 1, p = 0.011) with high comorbidity index (OR 1.508 [95% CI 1.148–1.98], p = 0.004) and those with complications (OR 3.155 [95% CI 1.202–8.279], p = 0.033). A hospital with a larger annual caseload was an independent predictor of adverse discharge disposition (OR 3.543 [95% CI 1.781–7.048], p < 0.001), whereas patients treated by physicians with high case volumes had significantly better outcomes (p = 0.006). The median total cost of hospitalization had increased by 6% from 2006 through 2010. Hospitals with a smaller case volume (OR 0.093, p < 0.001), private hospitals (OR 11.027, p < 0.001), nonteaching hospitals (OR 3.139, p = 0.003), and hospitals in the West compared with hospitals in Northeast and the Midwest (OR 1.885 [p = 0.033] and OR 2.897 [p = 0.031], respectively) were independent predictors of higher hospital cost. The mean length of hospital stay decreased from 2.03 days in 2006 to 1.55 days in 2010. There was no difference in the discharge disposition among academic versus nonacademic centers and rural versus urban hospitals (p > 0.05).

Conclusions

Elderly female patients with nonprivate insurance and high comorbidity index who underwent surgery at low-volume centers performed by a surgeon with a low annual case volume and the occurrence of postoperative complications were correlated with an adverse discharge disposition. High-volume, government-owned academic centers in the Northeast were associated with a lower cost incurred to the hospitals. It can be recommended that the widespread availability of this procedure across small, academic centers in rural areas may not only provide easier access to the patients but also reduces the total cost of hospitalization.