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1.
Chemistry ; 30(47): e202401755, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39031564

RESUMEN

The spatially resolvable multicolored microrods have potential applications in many fields. However, achieving spatially resolved multicolor luminescence tuning on the microrod with a fixed composition remains a daunting challenge. Herein, a strategy is proposed that allows for the tuning of spatially resolved, multicolored upconversion (UC) luminescence (UCL) along a 1D heterogeneous microrod by modifying the pulse width of an external laser. NaYbF4:1 % Ho is identified as an UCL color-adjustable material, exhibiting pulse width-dependent multicolored UCL, resulting in a significant regulation of the red/green (R/G) ratio from 0.1 to 10.3 as the pulse width is varied from 0.1 to 10 ms. Such variability can be ascribed to differences in the number of photons incident upon the microrod throughout the period necessary for the UC process to occur. Additionally, NaYbF4:1 %Tm and NaYF4:20 %Yb,1 %Ho are employed as materials that emit blue and green light, respectively, with their UCL colors largely unaffected by changes in the pulse width. Subsequently, a tip-modified epitaxial growth method is utilized to integrate both UCL color-adjustable and non-adjustable segments within the same microrod. Comparing with single-color or fixed multicolor microrods, our developed multisegmented emissive color adjustable 1D heterogeneous microrods have unique optical characteristics and can carry more optical information.

2.
Sensors (Basel) ; 24(13)2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-39000882

RESUMEN

Vibration measurements pose specific experimental challenges to be faced. In particular, optical methods can be used to obtain full-field vibration information. In this scenario, stereo-camera systems can be developed to obtain 3D displacement measurements. As vibration frequency increases, the common approach is to reduce camera exposure time to avoid blurred images, which can lead to under-exposed images and data loss, as well as issues with the synchronization of the stereo pair. Both of these problems can be solved by using high-intensity light pulses, which can produce high-quality images and guarantee camera synchronization since data is saved by both cameras only during the short-time light pulse. To this extent, high-power Light-Emitting Diodes (LEDs) can be used, but even if the LED itself can have a fast response time, specific electronic drivers are needed to ensure the desired timing of the light pulse. In this paper, a circuit is specifically designed to achieve high-intensity short-time light pulses in the range of 1 µs. A prototype of the designed board was assembled and tested to check its capability to respect the specification. Three different measurement methods are proposed and validated to achieve short-time light pulse measurements: shunt voltage measurement, direct photodiode measurement with a low-cost sensor, and indirect pulse measurement through a low-frame-rate digital camera.

3.
Sensors (Basel) ; 24(5)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38475153

RESUMEN

LiDAR has high accuracy and resolution and is widely used in various fields. In particular, phase-modulated continuous-wave (PhMCW) LiDAR has merits such as low power, high precision, and no need for laser frequency modulation. However, with decreasing signal-to-noise ratio (SNR), the noise on the signal waveform becomes so severe that the current methods to extract the time-of-flight are no longer feasible. In this paper, a novel method that uses deep neural networks to measure the pulse width is proposed. The effects of distance resolution and SNR on the performance are explored. Recognition accuracy reaches 81.4% at a 0.1 m distance resolution and the SNR is as low as 2. We simulate a scene that contains a vehicle, a tree, a house, and a background located up to 6 m away. The reconstructed point cloud has good fidelity, the object contours are clear, and the features are restored. More precisely, the three distances are 4.73 cm, 6.00 cm, and 7.19 cm, respectively, showing that the performance of the proposed method is excellent. To the best of our knowledge, this is the first work that employs a neural network to directly process LiDAR signals and to extract their time-of-flight.

4.
Nord J Psychiatry ; 78(2): 137-145, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38079191

RESUMEN

AIMS: To examine the association between pulse width and HRQoL measured within one week after electroconvulsive therapy (ECT) and at six-month follow-up in patients with unipolar or bipolar depression. METHODS: This was an observational register study using data from the Swedish National Quality Registry for ECT (2011-2019). Inclusion criteria were: age ≥18 years; index treatment for unipolar/bipolar depression; unilateral electrode placement; information on pulse width; EQ-5D measurements before and after ECT. Multiple linear regressions were performed to investigate the association between pulse width (<0.5 ms; 0.5 ms; >0.5 ms) and HRQoL (EQ-5D-3L index; EQ VAS) one week after ECT (primary outcome) and six months after ECT (secondary outcome). RESULTS: The sample included 5,046 patients with unipolar (82%) or bipolar (18%) depression. At first ECT session, 741 patients (14.7%) had pulse width <0.5 ms, 3,639 (72.1%) had 0.5 ms, and 666 (13.2%) had >0.5 ms. There were no statistically significant associations between pulse width and HRQoL one week after ECT. In the subsample of patients with an EQ-5D index recorded six months after ECT (n = 730), patients receiving 0.5 ms had significantly lower HRQoL (-0.089) compared to <0.5 ms, after adjusting for demographic and clinical characteristics (p = .011). The corresponding analysis for EQ VAS did not show any statistically significant associations. CONCLUSION: No robust associations were observed between pulse width and HRQoL after ECT. On average, significant improvements in HRQoL were observed one week and six months after ECT for patients with unipolar or bipolar disease, independent of the pulse width received.


Asunto(s)
Trastorno Bipolar , Trastorno Depresivo , Terapia Electroconvulsiva , Humanos , Adolescente , Trastorno Bipolar/terapia , Terapia Electroconvulsiva/efectos adversos , Calidad de Vida , Resultado del Tratamiento , Trastorno Depresivo/terapia
5.
Neurourol Urodyn ; 42(4): 770-777, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36840886

RESUMEN

INTRODUCTION/BACKGROUND: The pulse width (PW) parameter in sacral neuromodulation (SNM) is understudied, with no evidence-based guidance available on optimal PW for urinary indications. The aim of this prospective, randomized, single-blinded, 3 × 3 cross over design study was to estimate the effect of two PW settings (60 µs, 420 µs) compared to the industry standard (210 µs) on SNM efficacy, quality of life, and device parameters in patients who were stable and satisfied with their SNM treatment. METHODS/MATERIALS: Eligible patients were previously implanted and had urge incontinence or urgency-frequency with satisfaction on SNM at time of enrollment. Patients completed a 3-day voiding diary, validated questionnaires, and device interrogations with sensory threshold assessment at baseline and after a 4-week period on each of the three PW settings, to which they were randomized. Eighteen participants completed the study, as called for by power analysis. RESULTS: Eighteen patients were enrolled in the study. Mean age was 68 years and implant duration at the time of participation was 4.4 years. While PW variations did not produce significant differences in overall objective outcomes, device parameters, including sensory threshold amplitude and battery life differed significantly. Shortened PW necessitated higher amplitude while conserving battery life. Stimulus sensation location, quality, and intensity did not differ between PW. Standard PW was chosen by 11 patients after the study, 5 chose extended, and 2 chose shortened. Those who chose alternative PW achieved significant reductions in urinary frequency from enrollment -2.23 voids/day (p = 0.015). Upon sub-analysis, patients reporting "much better" or "very much better" on extended PW achieved significant reductions in urinary frequency and nocturia at 5.6 and 0.4, compared to 8.5 and 2.16 at baseline (p = 0.005, p = <0.001). Whereas those reporting "much better" or "very much better" on shortened PW achieved significant reductions in urinary frequency at 5.15 compared to 7.35 (p = 0.026). There were no adverse events or complications. CONCLUSIONS: Overall SNM effectiveness was unchanged with alternative PW; however, 39% of patients preferred alternative to standard PW and achieved significant improvements in urinary symptoms with such. Shorter PW can also provide savings in estimated battery life without sacrificing therapeutic efficacy.


Asunto(s)
Terapia por Estimulación Eléctrica , Vejiga Urinaria Hiperactiva , Humanos , Anciano , Vejiga Urinaria Hiperactiva/terapia , Calidad de Vida , Estudios Cruzados , Estudios Prospectivos , Estudios de Factibilidad , Resultado del Tratamiento , Poliuria/etiología
6.
Neurol Sci ; 44(3): 815-825, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36383263

RESUMEN

BACKGROUND: Deep brain stimulation (DBS) is a common treatment for Parkinson's disease. However, the clinical efficacy of short pulse width DBS (spDBS) compared with conventional DBS (cDBS) is still unknown. OBJECTIVE: This meta-analysis investigated the effectiveness of spDBS versus cDBS in patients with PD. METHODS: Four databases (PubMed, Cochrane, Web of Science, and Embase) were independently searched until October 2021 by two reviewers. We utilized the following scales and items: therapeutic windows (TW), efficacy threshold, side effect threshold, Movement Disorder Society-Sponsored Revision Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part III off-medication score, Speech Intelligence Test (SIT), and Freezing of Gait Questionnaire (FOG-Q). RESULTS: The analysis included seven studies with a total of 87 patients. The results indicated that spDBS significantly widened the therapeutic windows (0.99, 95% CI = 0.61 to 1.38) while increasing the threshold amplitudes of side effects (2.25, 95% CI = 1.69 to 2.81) and threshold amplitudes of effects (1.60, 95% CI = 0.84 to 2.36). There was no statistically significant difference in UPDRS part III, SIT, and FOG-Q scores between spDBS and cDBS groups, suggesting that treatment with both cDBS and spDBS may result in similar effects of improved dysarthria and gait disorders. CONCLUSIONS: Compared with cDBS, spDBS is effective in expanding TW. Both types of deep brain stimulation resulted in improved gait disorders and speech intelligibility.


Asunto(s)
Estimulación Encefálica Profunda , Trastornos Neurológicos de la Marcha , Enfermedad de Parkinson , Núcleo Subtalámico , Humanos , Enfermedad de Parkinson/terapia , Estimulación Encefálica Profunda/métodos , Trastornos Neurológicos de la Marcha/terapia , Resultado del Tratamiento
7.
Sensors (Basel) ; 23(18)2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37766041

RESUMEN

In this work, we propose a bipolar complementary pulse width modulation strategy based on the differential signaling system, and the modulation-demodulation methods are introduced in detail. The proposed modulation-demodulation strategy can effectively identify each symbol's start and end time so that the transmitter and receiver can maintain correct bit synchronization. The system with differential signaling has the advantages of not requiring channel state information and reducing background radiation. To further reduce the noise in the system, a multi-bandpass spectrum noise reduction method is proposed according to the spectrum characteristics of the received modulation signals. The proposed modulation method has an error bit rate of 10-5 at a signal-to-noise ratio of 7 dB. The fabricated optical communication system can stably transfer voice and text over a distance of 5.6 km.

8.
Scand J Med Sci Sports ; 32(10): 1456-1463, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35844045

RESUMEN

This study compared the acute responses of three neuromuscular electrical stimulation (NMES) methods on muscle torque-time integral (TTI) and neuromuscular fatigue. Narrow-pulse (0.2 ms; NP), wide-pulse (1 ms; WP), and tendon vibration superimposed onto wide-pulse (WP + VIB)-NMES conditions were applied to sixteen healthy individuals (n = 16) in three separate sessions in a randomized order. Stimulation intensity was set to elicit 20% of maximal voluntary contraction (MVC); the stimulus pattern comprised four sets of 20 repetitions (5 s On and 5 s Off) with a one-minute inter-set interval. TTI was measured for each NMES condition and MVC, voluntary activation (VA), peak twitch torque (Peaktwitch ), and peak soleus (EMGSOL ), medial (EMGMG ), and lateral gastrocnemius (EMGLG ) electromyography were measured before and immediately after each NMES condition. TTI was higher during WP + VIB (19.63 ± 6.34 MVC.s, mean difference = 3.66, p < 0.001, Cohen's d = 0.501) than during WP (15.97 ± 4.79 MVC.s) condition. TTI was higher during WP + VIB (mean difference = 3.79, p < 0.001, Cohen's d = 0.626) than during NP (15.84 ± 3.73 MVC.s) condition. MVC and Peaktwitch forces decreased (p ≤ 0.001) immediately after all conditions. No changes were observed for VA (p = 0.365). EMGSOL amplitude reduced (p = 0.040) only after NP, yet EMGLG and EMGMG amplitudes decreased immediately after all conditions (p = 0.003 and p = 0.013, respectively). WP + VIB produced a higher TTI than WP and NP-NMES, with similar amounts of neuromuscular fatigue across protocols. All NMES protocols induced similar amounts of peripheral fatigue and reduced EMG amplitudes.


Asunto(s)
Fatiga Muscular , Músculo Esquelético , Estimulación Eléctrica/métodos , Electromiografía , Humanos , Contracción Muscular , Fatiga Muscular/fisiología , Músculo Esquelético/fisiología , Torque
9.
Sensors (Basel) ; 22(17)2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36081065

RESUMEN

Vienna rectifiers are widely used, but they have problems of zero-crossing current distortion and midpoint potential imbalance. In this paper, an improved hybrid modulation strategy is proposed. According to the phase difference between the reference voltage vector and the input current vector, the dynamic current crossing distortion sector is divided at each phase current crossing, and the discontinuous pulse width modulation strategy is adopted in the sector to suppress the redundant small vector mutation and improve the current crossing distortion. To solve the problem of midpoint potential balance, a space vector modulation strategy is adopted outside the sector to control the midpoint potential balance by allocating the time of small vector action by voltage balance factor. Finally, the effectiveness of the proposed method is verified by simulation and experiment.

10.
Sensors (Basel) ; 22(17)2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-36080861

RESUMEN

The shift of the world in the past two decades towards renewable energy (RES), due to the continuously decreasing fossil fuel reserves and their bad impact on the environment, has attracted researchers all around the world to improve the efficiency of RES and eliminate problems that arise at the point of common coupling (PCC). Harmonics and un-balance in 3-phase voltages because of dynamic and nonlinear loads cause a lagging power factor due to inductive load, active power losses, and instability at the point of common coupling. This also happens due to a lack of system inertia in micro-grids. Passive filters are used to eliminate harmonics at both the electrical converter's input and output sides and improve the system's power factor. A Synchronous Reference Frame (SRF) control method is used to overcome the problem related to grid synchronization. The sine pulse width modulation (SPWM) technique provides gating signals to the switches of the multilevel inverter. A multi-layer feed forward neural network (ML-FFNN) is employed at the output of a system to minimize mean square error (MSE) by removing the errors between target voltages and reference voltages produced at the output of a trained model. Simulations were performed using MATLAB Simulink to highlight the significance of the proposed research study. The simulation results show that our proposed intelligent control scheme used for the suppression of harmonics compensated for reactive power more effectively than the SRF-based control methods. The simulation-based results confirm that the proposed ML-FFNN-based harmonic and reactive power control technique performs 0.752 better in terms of MAE, 0.52 for the case of MSE, and 0.222 when evaluating based on the RMSE.

11.
Angew Chem Int Ed Engl ; 61(45): e202212089, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36102873

RESUMEN

Different from organic dye/quantum dot possessing one luminescent center, upconversion luminescence (UCL) is actually a statistic of temporal behaviors of countless individual activators. Our experimental results have shown that the rise and decay dynamics of UCL is directly associated with the relative contribution of sensitizer-to-activator energy transfer and energy migration among sensitizers, which can be physically modulated by simply tuning the excitation laser. Therefore, dynamic UCL with record-wide 20-fold lifetime, ≈70-fold red-to-green intensity ratio, and reversibly definable emission color is easily realized by just modulating the excitation laser. Moreover, this generally applicable strategy only requires a simplest-possible UCL system whereas prevalent material engineering such as complicated composition design, sophisticated core-shell construction, or tedious chemical synthesis, is no longer needed.

12.
Neurourol Urodyn ; 40(1): 522-528, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33305838

RESUMEN

AIM: Pulse width (PW) influences neuromodulation by its impact on nerve fiber recruitment. A paucity of data regarding the manipulation of PW in sacral neuromodulation (SNM) exists. This study describes the clinical features and outcomes of PW manipulation for unsatisfactory SNM therapy. METHODS: A retrospective, single-institution review was performed of reprogrammed SNM patients between 2010 and 2019. Two cohorts were created: those with PW changes ± program changes and age-matched controls with program changes alone. Patients lacking follow-up and non-InterStim II models were excluded. RESULTS: Out of 710 SNM interrogations, 147 (20.7%) had PW changes and 80 met inclusion criteria. Most PW changes were shortened (61/80, 76.3%). Clinical features did not differ between cohorts except by indication for reprogramming. The most common indication for PW change was painful stimulation (34/80, 43%), whereas in controls it was suboptimal efficacy (76/80, 95%). Clinical success was stratified by indication. There was a higher improvement in efficacy in the PW cohort (61%, 17/28 vs. 36%, 27/76, p = .02). PW manipulation successfully relieved painful stimulation in 50% (17/34 vs. 0/3, p = .23), which was more likely with a shortened compared to extended PW (14/15, 93.3% vs. 0/6, 0%, p < .01). PW resulted in improvement in localization of the stimulus in 94% (17/18 vs. 0/1, p = .10). The subsequent lead revision or explant was significantly higher in the PW cohort (43% vs. 25%, p = .03). CONCLUSION: PW manipulation may aid the salvage of unsatisfactory SNM therapy. These findings represent an initial assessment of the role of PW in SNM, particularly regarding the efficacy and painful stimuli. The further prospective investigation is warranted.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Estimulación Eléctrica Transcutánea del Nervio/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
13.
Eur Arch Psychiatry Clin Neurosci ; 271(3): 465-473, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31832757

RESUMEN

There is a lack of research regarding 0.5-ms pulse width (PW) in bilateral electroconvulsive therapy (ECT). The aim of this study was to compare the efficacy and number of treatment sessions between groups receiving 0.5-ms and 1-ms PW ECT. Ninety-four patients with unipolar major depression treated with acute bilateral ECT were analysed retrospectively, grouped as consecutive patients treated with 0.5-ms PW ECT (n = 47), and age- and sex-matched patients treated with 1-ms PW ECT. Clinical and ECT data were extracted from clinical records. Symptom evaluations and global cognitive screening at baseline and post-ECT were administered by trained psychiatrists. The Hamilton Rating Scale for Depression (HDRS-21) was rated weekly. Efficacy and number of treatment sessions were compared between groups. PW was explored as a predictor of mean decrease in HDRS and number of treatment sessions by regression models. Group characteristics did not differ at baseline. The mean decrease in HDRS in the 0.5- and 1-ms PW [25.85 (7.79) vs. 24.33 (6.99), respectively], response (95.7% vs. 97.9%), remission (87.2% vs. 80.9%) and mean number of treatment sessions [11.28 (3.85) vs. 11.34 (3.36)] were not significantly different. Episode duration and severity, and previous ECT predicted HDRS decrease. Severity at baseline and the 6th session, the dosing method and the last ECT treatment dose predicted the number of treatment sessions needed. PW was not significant in the regressions models. The results suggest that both PWs perform similarly in bilateral ECT for depression, resulting in equivalent antidepressant efficacy and number of treatment sessions needed.


Asunto(s)
Trastorno Depresivo Mayor/terapia , Terapia Electroconvulsiva/métodos , Evaluación de Resultado en la Atención de Salud , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
14.
Stereotact Funct Neurosurg ; 99(4): 281-286, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33227807

RESUMEN

The benefit of short pulse width stimulation in patients suffering from essential tremor (ET) refractory to thalamic deep brain stimulation remains controversial. Here, we add to the minimal body of evidence available by reporting the effect of this type of stimulation in 3 patients with a persistent and severe intention tremor component despite iterative DBS setting adjustments. While a reduction in pulse width to 30 µs initially showed promise in these patients by improving tremor control and mitigating cerebellar side effects arguably by widening the therapeutic window, these benefits seemed to dissipate during early follow-up. Our experience supports the need for measuring longer-term outcomes when reporting the usefulness of this mode of stimulation in ET.


Asunto(s)
Estimulación Encefálica Profunda , Temblor Esencial , Temblor Esencial/terapia , Humanos , Tálamo , Temblor/terapia
15.
Sensors (Basel) ; 21(3)2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33499338

RESUMEN

A three-dimensional (3D) image sensor based on Single-Photon Avalanche Diode (SPAD) requires a time-to-digital converter (TDC) with a wide dynamic range and fine resolution for precise depth calculation. In this paper, we propose a novel high-performance TDC for a SPAD image sensor. In our design, we first present a pulse-width self-restricted (PWSR) delay element that is capable of providing a steady delay to improve the time precision. Meanwhile, we employ the proposed PWSR delay element to construct a pair of 16-stages vernier delay-rings to effectively enlarge the dynamic range. Moreover, we propose a compact and fast arbiter using a fully symmetric topology to enhance the robustness of the TDC. To validate the performance of the proposed TDC, a prototype 13-bit TDC has been fabricated in the standard 0.18-µm complementary metal-oxide-semiconductor (CMOS) process. The core area is about 200 µm × 180 µm and the total power consumption is nearly 1.6 mW. The proposed TDC achieves a dynamic range of 92.1 ns and a time precision of 11.25 ps. The measured worst integral nonlinearity (INL) and differential nonlinearity (DNL) are respectively 0.65 least-significant-bit (LSB) and 0.38 LSB, and both of them are less than 1 LSB. The experimental results indicate that the proposed TDC is suitable for SPAD-based 3D imaging applications.

16.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(2): 141-144, 2021 Apr 08.
Artículo en Zh | MEDLINE | ID: mdl-33825371

RESUMEN

According to the collection principles and characteristics of the pulse physiological signals of traditional Chinese medicine, combined with the international standard requirements of the pulse graph force transducer (ISO 19614:2017-05), a special force sensor component that can be used for a complete and objective collection of pulse signals has been developed, this sensor meets the requirements of industrialization. The sensor can measure the pulse amplitude and width signals of the cunpart of the human body. In addition, three sensors can be placed at the cun, guan, chi part at the same time, so that the "three body parts and nine pulse-taking sites" can be realized synchronously. After the sensor has been verified, the results meet the relevant requirements of international standard. The consistency of the result can be reached to 92.3% compared with the diagnosis result of clinical TCM experts.


Asunto(s)
Pulso Arterial , Transductores , Frecuencia Cardíaca , Humanos , Medicina Tradicional China
17.
Mov Disord ; 35(1): 101-108, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31571270

RESUMEN

BACKGROUND: Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective therapy for selected Parkinson's disease patients with motor fluctuations, but can adversely affect speech and axial symptoms. The use of short pulse width (PW) has been shown to expand the therapeutic window acutely, but its utility in reducing side effects in chronic STN-DBS patients has not been evaluated. OBJECTIVE: To compare the effect of short PW settings using 30-µs with conventional 60-µs settings on stimulation-induced dysarthria in Parkinson's disease patients with previously implanted STN-DBS systems. METHODS: In this single-center, double-blind, randomized crossover trial, we assigned 16 Parkinson's disease patients who had been on STN-DBS for a mean of 6.5 years and exhibited moderate dysarthria to 30-µs or 60-µs settings for 4 weeks followed by the alternative PW setting for a further 4 weeks. The primary outcome was difference in dysarthric speech measured by the Sentence Intelligibility Test between study baseline and the 2 PW conditions. Secondary outcomes included motor, nonmotor, and quality of life measures. RESULTS: There was no difference in the Sentence Intelligibility Test scores between baseline and the 2 treatment conditions (P = 0.25). There were also no differences noted in motor, nonmotor, or quality of life scores. The 30-µs settings were well tolerated, and adverse event rates were similar to those at conventional PW settings. Post hoc analysis indicated that patients with dysarthria and a shorter duration of DBS may be improved by short PW stimulation. CONCLUSIONS: Short PW settings using 30 µs did not alter dysarthric speech in chronic STN-DBS patients. A future study should evaluate whether patients with shorter duration of DBS may be helped by short PW settings. © 2019 International Parkinson and Movement Disorder Society.


Asunto(s)
Estimulación Encefálica Profunda , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/fisiopatología , Resultado del Tratamiento , Anciano , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida
18.
Mov Disord ; 35(12): 2261-2269, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32979290

RESUMEN

BACKGROUND: Subthalamic nucleus deep brain stimulation (STN-DBS) is a widely used treatment for Parkinson's disease (PD) patients with motor complications, but can result in adverse effects (AEs) in a significant proportion of treated patients. The use of novel programming features including short pulse width (PW) and directional steering in alleviating stimulation-induced AEs has not been explored. OBJECTIVE: To determine if programming with short PW, directional steering, or the combination of these novel techniques can improve stimulation-induced dysarthria, dyskinesia, and pyramidal AEs. METHODS: Thirty-two consecutive PD patients who experienced reversible AEs of STN-DBS had optimization of their settings using either short PW, directional steering, or the combination, while ensuring equivalent control of motor symptoms. Pairwise comparisons of pre- and post-optimization adverse effect ratings were made. Patients were left on the alternative setting with the greatest benefit and followed up at 6 months. Modeling of volume of tissue activated (VTA) and charge per pulse (Qp) calculations were used to explore potential underlying mechanisms of any differences found. RESULTS: There were significant improvements in stimulation-induced dysarthria, dyskinesia, and pyramidal side effects after optimization. At 6 months, mean AE ratings remained significantly improved compared to pre-optimization ratings. Different patterns of shift in VTA for each AE, and Qp could be used to explain improvements using novel techniques. CONCLUSIONS: Stimulation-induced dysarthria, dyskinesia, and pyramidal AEs induced by STN-DBS can be improved by using novel programming techniques. These represent additional tools to conventional methods that can be used to address these AEs. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Estimulación Encefálica Profunda , Discinesias , Enfermedad de Parkinson , Núcleo Subtalámico , Humanos , Enfermedad de Parkinson/terapia , Resultado del Tratamiento
19.
Stereotact Funct Neurosurg ; 98(5): 331-336, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32668433

RESUMEN

INTRODUCTION: A wide range of pulse widths (PWs) has been used in globus pallidus internus (GPi) deep brain stimulation (DBS) for dystonia. However, no specific PW has demonstrated clinical superiority, and the paradigm may differ among DBS centers. OBJECTIVE: To investigate how different paradigms of PWs in GPi DBS for dystonia affect implantable pulse generator (IPG) longevities and energy consumption. METHODS: Thirty-nine patients with dystonia treated with bilateral GPi DBS at 2 Swedish DBS centers from 2005 to 2015 were included. Different PW paradigms were used at the 2 centers, 60-90 µs (short PWs) and 450 µs (long PW), respectively. The frequency of IPG replacements, pulse effective voltage (PEV), IPG model, pre-/postoperative imaging, and clinical outcome based on the clinical global impression (CGI) scale were collected from the medical charts and compared between the 2 groups. RESULTS: The average IPG longevity was extended for the short PWs (1,129 ± 50 days) compared to the long PW (925 ± 32 days; χ2 = 12.31, p = 0.0005, log-rank test). IPG longevity correlated inversely with PEV (Pearson's r = -0.667, p < 0.0001). IPG longevities did not differ between Kinetra® and Activa® PC in the short (p = 0.319) or long PW group (p = 0.858). Electrode distances to the central sensorimotor region of the GPi did not differ between the short or long PW groups (p = 0.595). Pre- and postoperative CGI did not differ between groups. CONCLUSIONS: Short PWs were associated with decreased energy consumption and increased IPG longevity. These effects were not dependent on the IPG model or the anatomic location of the electrodes. PWs did not correlate with symptom severities or clinical outcomes. The results suggest that the use of short PWs might be more energy efficient and could therefore be preferred initially when programming patients with GPi DBS for dystonia.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Distonía/diagnóstico por imagen , Distonía/terapia , Electrodos Implantados , Globo Pálido/diagnóstico por imagen , Anciano , Estimulación Encefálica Profunda/tendencias , Electrodos Implantados/tendencias , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
20.
IEEE J Solid-State Circuits ; 55(11): 2947-2958, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33281206

RESUMEN

This paper presents a millimeter-scale CMOS 64×64 single charged particle radiation detector system for external beam cancer radiotherapy. A 1×1 µm2 diode measures energy deposition by a single charged particle in the depletion region, and the array design provides a large detection area of 512×512 µm2. Instead of sensing the voltage drop caused by radiation, the proposed system measures the pulse width, i.e., the time it takes for the voltage to return to its baseline. This obviates the need for using power-hungry and large analog-to-digital converters. A prototype ASIC is fabricated in TSMC 65 nm LP CMOS process and consumes the average static power of 0.535 mW under 1.2 V analog and digital power supply. The functionality of the whole system is successfully verified in a clinical 67.5 MeV proton beam setting. To our' knowledge, this is the first work to demonstrate single charged particle detection for implantable in-vivo dosimetry.

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