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Kelly E Lyons

Publications and source records attributed to Kelly E Lyons.

At least 19 recordsLinked to original sources
PubMed2006

Electronic motor function diary for patients with Parkinson's disease: a feasibility study.

Parkinson's disease (PD) studies often measure daily motor function with paper diaries resulting in issues of compliance and reliability. The feasibility and compliance of PD patients using electronic diaries were examined. Twelve patients completed diaries for 7 consecutive days. Diaries recorded motor function, time and date of each half-hour entry and had an alarm as notification of missed entries. Entry compliance was 99.98% within 24h and average response time during awake hours was 63 min. Electronic diaries could be operated by PD patients, provided valuable information about response patterns and resulted in average response compliance of approximately 1h.

Adult↗
PubMed2006

Pain-pressure threshold in patients with Parkinson's disease with and without dyskinesia.

The objective of this study was to determine if Parkinson's disease (PD) patients with dyskinesia have a lower pain pressure threshold (PPT) than patients without dyskinesia and healthy controls. This was an outpatient, controlled study. We studied 25 healthy controls, 25 PD patients without dyskinesia and 25 PD patients with dyskinesia. A J Tech Pain Track algometer was used to measure PPT. No differences were found in PPT between controls and PD patients with or without dyskinesia. Patients and control women had a lower PPT than men. In conclusion, the presence of dyskinesia in PD patients does not appear to decrease PPT.

Aged↗
PubMed2006

Stimulation of the motor cortex for disabling essential tremor.

OBJECTIVE: To examine the safety and efficacy of targeted stimulation of the motor cortex as a treatment for essential tremor (ET). PATIENTS AND METHODS: At the University of Kansas Medical Center, two patients with essential tremor received stimulation of the (contralateral) motor cortex using an investigational implantable pulse generator (IPG). Patients were evaluated with the Fahn Tolosa Marin tremor rating scale (TRS) at baseline, 1 week and 4 weeks after surgery, both with stimulation turned on and turned off. Both patients also received neuropsychological assessments at baseline and again after surgery. RESULTS: Patient 1 was a 75-year-old male with tremor for 20 years. His baseline total TRS score was 61 and his TRS 1 month after surgery was 57. His IPG was set at 30 Hz, 3 mA and 250 micros pulse width. Patient 2 was a 60-year-old male with tremor for over 10 years. His baseline total TRS was 47 and it was 43, 1 month after surgery. His IPG was set at 50 Hz, 5 mA and 250 micros pulse width. There were no adverse effects. CONCLUSION: Cortical stimulation of the primary hand motor cortex contralateral to the dominant hand was ineffective for the treatment of ET with the stimulation parameters used in this study. Future research examining other stimulation parameters is necessary to determine if there is a role for cortical stimulation in the treatment of ET.

Aged↗
PubMed2006

Postural tremor suppression is dependent on thalamic stimulation frequency.

Deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) reduces tremor in people with essential tremor (ET), yet the dependence of tremor suppression on stimulation frequency remains unclear. To address this issue, we tested tremor suppression for three 15-second measurements during a variety of stimulation frequencies in 11 ET patients treated with VIM DBS. Stimulation frequencies at or above 100 Hz produced maximal benefit; higher frequencies provided no additional benefit. If this short-term measure predicts long-term response in routine activities at home, then this stimulation frequency setting will prolong battery half-life compared to higher frequency settings. These findings suggest that ET patients treated with VIM DBS may receive adequate benefit from stimulation frequencies about 100 Hz and this setting compared to commonly used higher settings will prolong battery life of surgically implanted pulse generators.

Aged↗
PubMed2006

Deep brain stimulation: preoperative issues.

Numerous factors need to be taken into account in deciding whether a patient with Parkinson's disease (PD) is a candidate for deep brain stimulation. Patient-related personal factors including age and the presence of other comorbid disorders need to be considered. Neuropsychological and neuropsychiatric concerns relate both to the presurgical status of the patient and to the potential for surgery to result in new problems postoperatively. A number of factors related to the underlying PD need to be considered, including the specific parkinsonian motor indications (e.g., tremor, bradykinesia, gait dysfunction), previous medical therapies, including benefit from current therapy and adverse effects, and past surgical treatments. Definable causes of Parkinsonism, particularly atypical Parkinsonisms, should be considered. Finally, methods of evaluating outcomes should be defined and formalized. This is a report from the Consensus on Deep Brain Stimulation for Parkinson's Disease, a project commissioned by the Congress of Neurological Surgeons and the Movement Disorder Society (MDS). The report has been endorsed by the Scientific Issues Committee of the MDS and the American Society of Stereotactic and Functional Neurosurgery. It outlines answers to a series of questions developed to address all aspects of deep brain stimulation preoperative decision-making.

Brain↗
PubMed2006

Deep brain stimulation: postoperative issues.

Numerous factors need to be taken into account when managing a patient with Parkinson's disease (PD) after deep brain stimulation (DBS). Questions such as when to begin programming, how to conduct a programming screen, how to assess the effects of programming, and how to titrate stimulation and medication for each of the targeted sites need to be addressed. Follow-up care should be determined, including patient adjustments of stimulation, timing of follow-up visits and telephone contact with the patient, and stimulation and medication conditions during the follow-up assessments. A management plan for problems that can arise after DBS such as weight gain, dyskinesia, axial symptoms, speech dysfunction, muscle contractions, paresthesia, eyelid, ocular and visual disturbances, and behavioral and cognitive problems should be developed. Long-term complications such as infection or erosion, loss of effect, intermittent stimulation, tolerance, and pain or discomfort can develop and need to be managed. Other factors that need consideration are social and job-related factors, development of dementia, general medical issues, and lifestyle changes. This report from the Consensus on Deep Brain Stimulation for Parkinson's Disease, a project commissioned by the Congress of Neurological Surgeons and the Movement Disorder Society, outlines answers to a series of questions developed to address all aspects of DBS postoperative management and decision-making with a systematic overview of the literature (until mid-2004) and by the expert opinion of the authors. The report has been endorsed by the Scientific Issues Committee of the Movement Disorder Society and the American Society of Stereotactic and Functional Neurosurgery.

Bacterial Infections↗
PubMed2006

Subthalamic nucleus deep brain stimulation: summary and meta-analysis of outcomes.

Subthalamic nucleus (STN) deep brain stimulation (DBS) is currently the most common therapeutic surgical procedure for patients with Parkinson's disease (PD) who have failed medical management. However, a recent summary of clinical evidence on the effectiveness of STN DBS is lacking. We report the results of such a systematic review and meta-analysis. A comprehensive review of the literature using Medline and Ovid databases from 1993 until 2004 was conducted. Estimates of change in absolute Unified Parkinson's Disease Rating Scale (UPDRS) scores after surgery were generated using random-effects models. Sources of heterogeneity were explored with meta-regression models, and the possibility of publication bias was evaluated. Patient demographics, reduction in medication requirements, change in dyskinesia, daily offs, quality of life, and a ratio of postoperative improvement from stimulation compared to preoperative improvement by medication from each study were tabulated and average scores were calculated. Adverse effects from each study were summarized. Thirty-seven cohorts were included in the review. Twenty-two studies with estimates of standard errors were included in the meta-analysis. The estimated decreases in absolute UPDRS II (activities of daily living) and III (motor) scores after surgery in the stimulation ON/medication off state compared to preoperative medication off state were 13.35 (95% CI: 10.85-15.85; 50%) and 27.55 (95% CI: 24.23-30.87; 52%), respectively. Average reduction in L-dopa equivalents following surgery was 55.9% (95% CI: 50%-61.8%). Average reduction in dyskinesia following surgery was 69.1% (95% CI: 62.0%-76.2%). Average reduction in daily off periods was 68.2% (95% CI: 57.6%-78.9%). Average improvement in quality of life using PDQ-39 was 34.5% +/- 15.3%. Univariable regression showed improvements in UPDRS III scores were significantly greater in studies with higher baseline UPDRS III off scores, increasing disease duration prior to surgery, earlier year of publication, and higher baseline L-dopa responsiveness. Average baseline UPDRS III off scores were significantly lower (i.e., suggesting milder disease) in later than in earlier studies. In multivariable regression, L-dopa responsiveness, higher baseline motor scores, and disease duration were independent predictors of greater change in motor score. No evidence of publication bias in the available literature was found. The most common serious adverse event related to surgery was intracranial hemorrhage in 3.9% of patients. Psychiatric sequelae were common. Synthesis of the available literature indicates that STN DBS improves motor activity and activities of daily living in advanced PD. Differences between available studies likely reflect differences in patient populations and follow-up periods. These data provide an estimate of the magnitude of the treatment effects and emphasize the need for controlled and randomized studies.

Deep Brain Stimulation↗
PubMed2006

Open-label trial regarding the use of acupuncture and yin tui na in Parkinson's disease outpatients: a pilot study on efficacy, tolerability, and quality of life.

OBJECTIVES: This study evaluates the effects of sequential tui na massage, acupuncture, and instrument-delivered qigong for patients with Parkinson disease (PD) over a 6-month period. DESIGN: Patients received weekly treatments, which included tui na massage prior to acupuncture followed by instrument-delivered qigong. Each patient was assessed at baseline and at 6 months. SETTING: The setting was an outpatient research/academic clinic for patients with PD and nonacademic acupuncture clinic. SUBJECTS: Twenty-five (25) patients with idiopathic PD were the subjects. OUTCOME MEASURES: Before and after treatment patients were evaluated with the Unified Parkinson Disease Rating Scale (UPDRS), Hoehn and Yahr Staging (H&Y), Schwab and England Activities of Daily Living (S & E), Beck Depression Inventory (BDI), Parkinson's Disease Questionnaire (PDQ-39) quality of life assessment, and patient global assessments. RESULTS: There were no significant improvements in treatment measures; however, there was a 2.4-point worsening in UPDRS motor scores (24.0 versus 26.4, p = 0.018). There was a 16% improvement in the PDQ- 39 total score (23.2 versus 19.6, p = 0.044) and a 29% improvement in the BDI (9.6 versus 6.8, p = 0.006). Sixteen (16) patients reported moderate to marked improvement. There were no adverse effects. CONCLUSIONS: Acupuncture is safe and well tolerated in patients with PD. Most patients reported subjective improvement. The BDI and PDQ-39 total score, measuring depression and quality of life, demonstrated some improvement, but UPDRS motor scores worsened.

Activities of Daily Living↗
PubMed2006

Effects of bilateral subthalamic nucleus stimulation on sleep, daytime sleepiness, and early morning dystonia in patients with Parkinson disease.

OBJECT: The aim of this study was to assess the long-term effects of bilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) for Parkinson disease (PD) on sleep, daytime sleepiness, and early morning dystonia and to evaluate the relationship between total sleep time and motor function. METHODS: Patients who had undergone bilateral STN DBS and a follow-up evaluation of 6 months (89 patients), 12 months (83 patients), and 24 months (43 patients) were included in this study. The patients were preoperatively assessed using the Unified Parkinson's Disease Rating Scale (UPDRS) in the medication-on and -off conditions, and they completed patient diaries. A subset of patients also completed the Epworth Sleepiness Scale. These assessments were repeated postoperatively with stimulation. The UPDRS activities of daily living (ADL) and motor scores as well as total sleep hours were significantly improved at 6, 12, and 24 months poststimulation and with no medication compared with baseline values. Increased sleep time was significantly correlated with improvements in bradykinesia but not with tremor or rigidity. Patient-reported sleep problems and early morning dystonia were reduced after STN DBS. Antiparkinsonian medications were significantly reduced after STN DBS; however, there were no changes in excessive daytime sleepiness 6, 12, or 24 months after surgery. CONCLUSIONS: Bilateral STN DBS increased total sleep time and reduced patient-reported sleep problems and early morning dystonia for up to 24 months posttreatment. These changes in sleep were related to improvements in functioning, specifically those affected by bradykinesia. Despite significant reductions in antiparkinsonian medications, STN DBS did not reduce excessive daytime sleepiness.

Activities of Daily Living↗
PubMed2006

Long-term evaluation of deep brain stimulation of the thalamus.

OBJECT: The effects of thalamic deep brain stimulation (DBS) on essential tremor (ET) and Parkinson disease (PD) have been well documented, but there is a paucity of long-term data. The aim of this study was to evaluate the long-term safety and efficacy of DBS of the ventralis intermedius nucleus (VIM) of the thalamus for PD and ET. METHODS: Thirty-eight of 45 patients enrolled at five sites completed a 5-year follow-up study. There were 26 patients with ET and 19 with PD undergoing 29 unilateral (18 ET/11 PD) and 16 bilateral (eight ET/eight PD) procedures. Patients with ET were evaluated using the Tremor Rating Scale, and patients with PD were evaluated using the Unified Parkinson's Disease Rating Scale. The mean age of patients with ET was 70.2 years and 66.3 years in patients with PD. Unilaterally implanted patients with ET had a 75% improvement of the targeted hand tremor; those with bilateral implants had a 65% improvement in the left hand and 86% in the right compared with baseline. Parkinsonian patients with unilateral implants had an 85% improvement in the targeted hand tremor and those with bilateral implants had a 100% improvement in the left hand and 90% improvement in the right. Common DBS-related adverse events in patients receiving unilateral implants were paresthesia (45%) and pain (41%), and in patients receiving implants bilaterally dysarthria (75%) and balance difficulties (56%) occurred. Device-related surgical revisions other than IPG replacements occurred in 12 (27%) of the 45 patients. CONCLUSIONS: Thalamic stimulation is safe and effective for the long-term management of essential and Parkinsonian tremors. Bilateral stimulation can cause dysarthria and incoordination and should be used cautiously.

Activities of Daily Living↗
PubMed2005

Freezing of gait after bilateral subthalamic nucleus stimulation for Parkinson's disease.

OBJECTIVE: To determine the long-term effect of bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) on freezing of gait in Parkinson's disease patients. PATIENTS AND METHODS: Sixty-seven patients were followed 12 months after bilateral STN DBS and 32 patients were followed 24 months post-surgery. Patients were evaluated with the Unified Parkinson's Disease Rating Scale (UPDRS) with medications on and off at baseline and again in both conditions with stimulation on at follow-up. Specific attention was paid to the freezing item of the ADL section. RESULTS: Freezing scores in the medication off state improved significantly with stimulation at 1 and 2 years. In the medication on state there were no significant improvements in freezing. CONCLUSION: Off period freezing of gait is significantly improved with STN DBS up to 24 months; however, on period freezing is not affected by STN DBS.

Adult↗
PubMed2005

Preoperative clinical predictors of response to bilateral subthalamic stimulation in patients with Parkinson's disease.

BACKGROUND: Younger age and a response to a supra-threshold levodopa challenge have been reported to predict a favorable response to bilateral subthalamic nucleus (STN) stimulation. OBJECTIVE: To identify and evaluate clinical factors which predict a positive outcome after bilateral STN stimulation in patients with Parkinson's disease, using each patient's typical doses of antiparkinsonian medication rather than a supra-threshold levodopa challenge. METHODS: Forty-five Parkinson's disease patients who underwent bilateral STN implantation were included in the study. There were 33 men and 12 women. Mean age and disease duration were 59.4 and 12.7 years, respectively. All patients underwent Unified Parkinson Disease Rating Scale (UPDRS) evaluations in the medication off and on states at baseline and postsurgically with stimulation on at 3, 6 and 12 months. The percentage improvement in UPDRS motor scores at baseline (medication off vs. on) was compared with the percentage improvement after stimulation optimization (baseline medication off vs. follow-up medication off/stimulation on). RESULTS: The preoperative percentage improvement in UPDRS motor scores with antiparkinsonian medications was predictive of the postoperative percentage improvement in the UPDRS motor scores in the medication off/stimulation on state (r = 0.53, p < 0.001). However, preoperative UPDRS motor scores in the medication on state were more strongly correlated with the postsurgical effect of stimulation (r = 0.64, p < 0.001). The postoperative improvement in UPDRS motor scores with stimulation did not correlate with age, disease duration or time to programming optimization. CONCLUSIONS: The preoperative percentage improvement in UPDRS motor scores with antiparkinsonian medications and UPDRS motor score in the medication on state at baseline are the strongest clinical predictors of responsiveness to bilateral STN stimulation.

Adult↗
PubMed2005

Quality of life in Essential Tremor Questionnaire (QUEST): development and initial validation.

BACKGROUND/OBJECTIVE: Essential tremor (ET) can diminish functioning and quality of life (QOL) but generic QOL measures may be relatively insensitive to ET and its therapies. We sought to develop an ET-specific measure that might be more sensitive, acceptable to patients, relatively brief, and easily used. DESIGN/METHODS: A sample of 200 patients (average age 70 years, range 30-91; average disease duration 15 years) rated the extent to which tremor impacts a function or state, tremor severity in various body parts, perceived health, and overall QOL. Responses to this initial questionnaire were subjected to principal components analysis (PCA). Inspection of factor coordinates, Eigenvalues, variance accounted for, and correlation matrices were used to select items for confirmatory PCA. Final scale reliability was assessed using Cronbach's alpha. Validity was evaluated by correlations between QOL scales and self-rated tremor severity. RESULTS: PCA of 65 initial items yielded 11 factors accounting for 71% of variance. Six factors were discarded. Two items were eliminated for not loading on a factor and 33 for perceived redundancy. Confirmatory PCA of the retained 30 items yielded an almost identical factor structure (six factors, 70% of variance accounted for, and similar item loadings). Because two factors had very few items loading on them, these two factors were combined into one scale. The final measure has five scales: Physical, Psychosocial, Communication, Hobbies/Leisure, and Work/Finance. Reliability was excellent for the whole instrument and four scales (> or =0.89), and good for the Work/Finance scale (0.79). Severity of voice and head tremor were the best correlates of Communication (0.70 and 0.35), while the Physical scale was related to right and left upper extremity tremor (0.59 and 0.56). Scales correlated more highly with patients' rating of their overall QOL than their health perception. CONCLUSIONS: A brief, 30-item, ET-specific QOL scale with excellent reliability was developed. Preliminary validity data are encouraging. The Quality of Life in Essential Tremor Questionnaire (QUEST) promises to facilitate QOL measurement in ET.

Adult↗
PubMed2005

Long-term benefits in quality of life provided by bilateral subthalamic stimulation in patients with Parkinson disease.

OBJECT: The goals of this study were to evaluate long-term benefits in quality of life in patients with Parkinson disease (PD) after bilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) and to evaluate the relationship between improvements in motor function and quality of life. METHODS: Seventy-one patients who received bilateral STN stimulation implants and participated in follow-up review for at least 12 months were included in the study. Fifty-nine patients participated in a 12-month follow-up review and 43 patients in a follow-up review lasting at least 24 months. Patients' symptoms were assessed preoperatively by using the Unified PD Rating Scale (UPDRS) in the "medication-on" and "medication-off' conditions and quality of life was examined using the 39-item PD Questionnaire (PDQ-39). Patient evaluations were repeated postoperatively during periods of stimulation. The UPDRS activities of daily living (ADL) and motor scores as well as the PDQ-39 total, mobility, ADL, emotional well-being, stigma, and bodily discomfort scores were significantly improved at 12 months compared with baseline scores; the UPDRS ADL and motor scores as well as the PDQ-39 total, mobility, ADL, stigma, and bodily discomfort scores were significantly improved at the longest follow-up examination compared with baseline scores. There was a strong correlation between UPDRS motor and ADL scores and the PDQ-39 total, mobility, and ADL scores. Further analyses indicated that improvements in tremor were only correlated with PDQ-39 ADL subscale scores and rigidity was not correlated with any aspect of quality of life. Nevertheless, bradykinesia was strongly correlated with improvements in the PDQ-39 total, mobility, and ADL scores. CONCLUSIONS: Improvements in quality of life following bilateral DBS of the STN are maintained in the long term. These improvements are strongly correlated with improvements in motor function, primarily with regard to bradykinesia.

Activities of Daily Living↗
PubMed2004

Surgical and hardware complications of subthalamic stimulation: a series of 160 procedures.

OBJECTIVE: To assess the surgical and hardware complications in a series of 81 consecutive patients undergoing subthalamic (STN) deep brain stimulation (DBS) for Parkinson disease (PD). METHODS: The authors prospectively documented surgical and hardware complications occurring at the time of surgery and at subsequent neurologic and surgical evaluations for an average of 17 months, ranging from 1 to 54 months. RESULTS: No patient had a serious surgical complication resulting in death or permanent neurologic deficit. One patient had an intracranial hemorrhage but with no permanent deficit. In follow-up, 2.5% had infections requiring system removal, 3.7% had infections requiring implantable pulse generator (IPG) removal, 12.5% had misplaced leads, and 26.2% had hardware complications including lead migration, lead fracture, extension erosion, extension fracture, and IPG malfunction. CONCLUSION: Serious complications leading to permanent neurologic deficit are rare after STN DBS for advanced PD. However, long-term follow-up demonstrated that hardware complications are relatively common, having occurred in approximately 26% of these patients.

Adult↗
PubMed2004

Bilateral pallidotomy for severe dystonia in an 18-month-old child with glutaric aciduria.

Glutaric aciduria type 1 is an inborn error of metabolism due to deficiency of glutaryl-CoA dehydrogenase. This disorder mainly affects children. The majority of patients develop a dystonic-dyskinetic syndrome. The dystonia is painful and can cause significant disability. This report documents an 18-month-old child, the youngest reported, who underwent pallidotomy for disabling dystonia. The surgery improved dystonic symptoms, especially pain in this child with minor complications related to the procedure. Pallidotomy is a reasonable option for children with dystonic symptoms secondary to glutaric aciduria.

Dystonic Disorders↗