Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 17 de 17
Filter
1.
Neurorehabil Neural Repair ; 38(7): 479-492, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38842031

ABSTRACT

BACKGROUND: Movement disorders in children and adolescents with dyskinetic cerebral palsy (CP) are commonly assessed from video recordings, however scoring is time-consuming and expert knowledge is required for an appropriate assessment. OBJECTIVE: To explore a machine learning approach for automated classification of amplitude and duration of distal leg dystonia and choreoathetosis within short video sequences. METHODS: Available videos of a heel-toe tapping task were preprocessed to optimize key point extraction using markerless motion analysis. Postprocessed key point data were passed to a time series classification ensemble algorithm to classify dystonia and choreoathetosis duration and amplitude classes (scores 0, 1, 2, 3, and 4), respectively. As ground truth clinical scoring of dystonia and choreoathetosis by the Dyskinesia Impairment Scale was used. Multiclass performance metrics as well as metrics for summarized scores: absence (score 0) and presence (score 1-4) were determined. RESULTS: Thirty-three participants were included: 29 with dyskinetic CP and 4 typically developing, age 14 years:6 months ± 5 years:15 months. The multiclass accuracy results for dystonia were 77% for duration and 68% for amplitude; for choreoathetosis 30% for duration and 38% for amplitude. The metrics for score 0 versus score 1 to 4 revealed an accuracy of 81% for dystonia duration, 77% for dystonia amplitude, 53% for choreoathetosis duration and amplitude. CONCLUSIONS: This methodology study yielded encouraging results in distinguishing between presence and absence of dystonia, but not for choreoathetosis. A larger dataset is required for models to accurately represent distinct classes/scores. This study presents a novel methodology of automated assessment of movement disorders solely from video data.


Subject(s)
Athetosis , Cerebral Palsy , Dystonia , Video Recording , Humans , Adolescent , Cerebral Palsy/physiopathology , Cerebral Palsy/complications , Cerebral Palsy/classification , Cerebral Palsy/diagnosis , Male , Female , Child , Dystonia/physiopathology , Dystonia/diagnosis , Dystonia/classification , Dystonia/etiology , Athetosis/physiopathology , Athetosis/diagnosis , Athetosis/etiology , Lower Extremity/physiopathology , Machine Learning
2.
J Perianesth Nurs ; 38(1): 33-38, 2023 02.
Article in English | MEDLINE | ID: mdl-35753934

ABSTRACT

PURPOSE: The purpose of this pilot project case series is to describe the use of preoperative cryoneurolysis for 10 patients presenting for total knee arthroplasty (TKA). DESIGN: Descriptive research design. METHODS: Billing codes were used to identify 10 patients who had previously undergone TKA, preoperative cryoneurolysis and physical therapy (PT) at a Midwestern community hospital. Data collected included anesthetic management strategies, multimodal analgesic therapies, postanesthesia care unit pain scores (PACU), pain scores during physical therapy, and achievement of a range of motion during physical therapy. FINDINGS: Nine of 10 patients who received preoperative cryoneurolysis had PACU pain scores of 0 (0-10 scale) up to 90 minutes postoperatively. Pain scores immediately following cryoneurolysis therapy were reduced in all patients reporting pain greater than 0 (1-10 pain scale) before their treatment. Increased active range of motion trends were noted with reports of decreased pain scores during postoperative physical therapy sessions. CONCLUSIONS: This pilot project case series demonstrates potential benefits of using preoperative cryoneurolysis to provide postoperative pain control and aid with physical therapy recovery following TKA.


Subject(s)
Arthroplasty, Replacement, Knee , Humans , Arthroplasty, Replacement, Knee/adverse effects , Pilot Projects , Pain, Postoperative/etiology , Analgesics , Pain Measurement , Treatment Outcome
3.
Mayo Clin Proc ; 95(10): 2099-2109, 2020 10.
Article in English | MEDLINE | ID: mdl-33012341

ABSTRACT

OBJECTIVE: To study whether combining vital signs and electrocardiogram (ECG) analysis can improve early prognostication. METHODS: This study analyzed 1258 adults with coronavirus disease 2019 who were seen at three hospitals in New York in March and April 2020. Electrocardiograms at presentation to the emergency department were systematically read by electrophysiologists. The primary outcome was a composite of mechanical ventilation or death 48 hours from diagnosis. The prognostic value of ECG abnormalities was assessed in a model adjusted for demographics, comorbidities, and vital signs. RESULTS: At 48 hours, 73 of 1258 patients (5.8%) had died and 174 of 1258 (13.8%) were alive but receiving mechanical ventilation with 277 of 1258 (22.0%) patients dying by 30 days. Early development of respiratory failure was common, with 53% of all intubations occurring within 48 hours of presentation. In a multivariable logistic regression, atrial fibrillation/flutter (odds ratio [OR], 2.5; 95% CI, 1.1 to 6.2), right ventricular strain (OR, 2.7; 95% CI, 1.3 to 6.1), and ST segment abnormalities (OR, 2.4; 95% CI, 1.5 to 3.8) were associated with death or mechanical ventilation at 48 hours. In 108 patients without these ECG abnormalities and with normal respiratory vitals (rate <20 breaths/min and saturation >95%), only 5 (4.6%) died or required mechanical ventilation by 48 hours versus 68 of 216 patients (31.5%) having both ECG and respiratory vital sign abnormalities. CONCLUSION: The combination of abnormal respiratory vital signs and ECG findings of atrial fibrillation/flutter, right ventricular strain, or ST segment abnormalities accurately prognosticates early deterioration in patients with coronavirus disease 2019 and may assist with patient triage.


Subject(s)
Arrhythmias, Cardiac/diagnostic imaging , Coronavirus Infections/physiopathology , Electrocardiography/statistics & numerical data , Emergency Service, Hospital/statistics & numerical data , Pneumonia, Viral/physiopathology , Time-to-Treatment/statistics & numerical data , Adult , Betacoronavirus , COVID-19 , Female , Humans , Male , Middle Aged , Pandemics , Prognosis , SARS-CoV-2
5.
Elife ; 52016 09 28.
Article in English | MEDLINE | ID: mdl-27677848

ABSTRACT

Hippocampal place field sequences are supported by sensory cues and network internal mechanisms. In contrast, sharp-wave (SPW) sequences, theta sequences, and episode field sequences are internally generated. The relationship of these sequences to memory is unclear. SPW sequences have been shown to support learning and have been assumed to also support episodic memory. Conversely, we demonstrate these SPW sequences were present in trained rats even after episodic memory was impaired and after other internal sequences - episode field and theta sequences - were eliminated. SPW sequences did not support memory despite continuing to 'replay' all task-related sequences - place- field and episode field sequences. Sequence replay occurred selectively during synchronous increases of population excitability -- SPWs. Similarly, theta sequences depended on the presence of repeated synchronized waves of excitability - theta oscillations. Thus, we suggest that either intermittent or rhythmic synchronized changes of excitability trigger sequential firing of neurons, which in turn supports learning and/or memory.


Subject(s)
Action Potentials , Hippocampus/physiology , Neuronal Plasticity , Neurons/physiology , Animals , Learning , Memory, Episodic , Rats
6.
Ophthalmic Plast Reconstr Surg ; 32(2): e30-2, 2016.
Article in English | MEDLINE | ID: mdl-24841734

ABSTRACT

Pharmacologic inhibition of tumor necrosis factor-alpha (TNF-α) has been used in the management of a variety of inflammatory conditions. Recently, reports on the development of sarcoid-like granulomatous disease at multiple systemic sites after treatment with TNF-α inhibitors have emerged, although, to the authors' knowledge, orbital manifestations of this problem have not been previously described. A 48-year-old woman who received injections of adalimumab for the treatment of psoriatic arthritis developed right-sided orbital pain and inflammation. Orbital biopsy of a focal lesion demonstrated sarcoid-like granulomatosis, and a workup for other causes of this problem was noncontributory. This report represents the first documented case of this phenomenon in the orbit, and possible mechanisms are discussed in this presentation. Given the expanding role of TNF-α inhibitors and the increased frequency of their use, clinicians should be aware of this possible side effect.


Subject(s)
Adalimumab/adverse effects , Anti-Inflammatory Agents/adverse effects , Granuloma/chemically induced , Orbital Diseases/chemically induced , Sarcoidosis/chemically induced , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Administration, Oral , Arthritis, Psoriatic/drug therapy , Drug Therapy, Combination , Eye Pain/etiology , Female , Glucocorticoids/therapeutic use , Granuloma/diagnosis , Granuloma/drug therapy , Humans , Immunosuppressive Agents/adverse effects , Methotrexate/therapeutic use , Middle Aged , Orbital Diseases/diagnosis , Orbital Diseases/drug therapy , Prednisone/administration & dosage , Sarcoidosis/diagnosis , Sarcoidosis/drug therapy
7.
J Pediatr Ophthalmol Strabismus ; 51(3): 177-9, 2014.
Article in English | MEDLINE | ID: mdl-24804974

ABSTRACT

PURPOSE: To investigate the association between uncorrected or miscorrected refractive errors in children and headache, and to determine whether correction of refractive errors contributes to headache resolution. METHODS: Results of ophthalmic examination, including refractive error, were recorded at initial visit for headache. If resolution of headache on subsequent visits was not documented, a telephone call was placed to their caregivers to inquire whether headache had resolved. RESULTS: Of the 158 patients, 75.3% had normal or unchanged eye examinations, including refractions.Follow-up data were available for 110 patients. Among those, 32 received new or changed spectacle correction and 78 did not require a change in refraction.Headaches improved in 76.4% of all patients, whether with (71.9%) or without (78.2%) a change in refractive correction. The difference between these two groups was not statistically significant (P = .38). CONCLUSIONS: Headaches in children usually do not appear to be caused by ophthalmic disease, including refractive error. The prognosis for improvement is favorable, regardless of whether refractive correction is required.


Subject(s)
Headache/physiopathology , Refractive Errors/physiopathology , Child , Child, Preschool , Eyeglasses , Female , Humans , Male , Refraction, Ocular/physiology , Refractive Errors/therapy , Visual Acuity/physiology
8.
Neural Comput ; 25(7): 1891-925, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23724797

ABSTRACT

Shannon's seminal 1948 work gave rise to two distinct areas of research: information theory and mathematical coding theory. While information theory has had a strong influence on theoretical neuroscience, ideas from mathematical coding theory have received considerably less attention. Here we take a new look at combinatorial neural codes from a mathematical coding theory perspective, examining the error correction capabilities of familiar receptive field codes (RF codes). We find, perhaps surprisingly, that the high levels of redundancy present in these codes do not support accurate error correction, although the error-correcting performance of receptive field codes catches up to that of random comparison codes when a small tolerance to error is introduced. However, receptive field codes are good at reflecting distances between represented stimuli, while the random comparison codes are not. We suggest that a compromise in error-correcting capability may be a necessary price to pay for a neural code whose structure serves not only error correction, but must also reflect relationships between stimuli.


Subject(s)
Information Theory , Mathematics , Models, Neurological , Neurons/physiology , Animals , Humans , Nerve Net/physiology
9.
Opt Lett ; 36(16): 3293-5, 2011 Aug 15.
Article in English | MEDLINE | ID: mdl-21847238

ABSTRACT

We demonstrate the fabrication, simulation, and experimental results of a buried, homogeneous narrowband spectral filter with a periodic, hexagonal unit cell of air pockets, encapsulated in a fused silica substrate. The leaky waveguide is formed by depositing SiO(x) on an etched fused silica grating via plasma-enhanced chemical vapor deposition. Design principles of guided mode resonance filters were utilized to achieve a resonance with 60% reflectivity at a wavelength of 1.741 µm. The device demonstrates resonance with FWHM of 6 nm.

10.
J Opt Soc Am A Opt Image Sci Vis ; 28(7): 1462-9, 2011 Jul 01.
Article in English | MEDLINE | ID: mdl-21734746

ABSTRACT

We demonstrate the generation of a nondiffracting double helical beam using axicons and ±1 vortex phase plates in a common-path interferometric system. Using linear diffraction theory, a simple analytical expression describing beam propagation is shown to agree with both experiments and Fresnel-diffraction-based simulations. Experiments are performed using continuous laser light in addition to ultrafast pulses, demonstrating that the common-path arrangement and the diffraction theory work equally well for both cases.

11.
Opt Lett ; 36(5): 737-9, 2011 Mar 01.
Article in English | MEDLINE | ID: mdl-21368966

ABSTRACT

We used guided-mode resonance filters (GMRFs), fabricated using thin-film deposition and chemical etching, as intracavity feedback elements to stabilize and narrow the output spectrum in thulium-doped fiber oscillators operating in the 2 µm wavelength regime, producing linewidths of <700 pm up to 10 W power levels. A Tm fiber-based amplified spontaneous emission source was used to characterize the reflective properties of the GMRFs. Linewidths of 500 pm and a 7.3 dB reduction in transmission were measured on resonances.

12.
Opt Express ; 18(26): 27764-76, 2010 Dec 20.
Article in English | MEDLINE | ID: mdl-21197051

ABSTRACT

We designed, fabricated, and tested, polarization selective, graded-reflectivity resonant filters; based on a radial-gradient spatially-distributed, guided-mode resonance device architecture. The demonstrated filters have polarized spectral-resonance responses, distributed across their aperture extent, in the range between 1535 nm and 1540 nm wavelengths. Spectral sensitivity was observed on device tests, for wavelength changes as low as 0.2 nm. Using multiple lithographic exposures and biasing exposure methods, the devices were engineered to have a sub-aperture region, with no hard boundaries or diffraction anomalies.


Subject(s)
Optical Devices , Refractometry/instrumentation , Transducers , Equipment Design , Equipment Failure Analysis
13.
Opt Express ; 17(22): 20365-75, 2009 Oct 26.
Article in English | MEDLINE | ID: mdl-19997265

ABSTRACT

Novel all-dielectric beam shaping elements were developed based on guided mode resonance (GMR) filters. This was achieved by spatially varying the duty cycle of a hexagonal-cell GMR filter, to locally detune from the resonant condition, which resulted in modified wavelength dependent reflection and transmission profiles, across the device aperture. This paper presents the design, fabrication, and characterization of the device and compares simulations to experimental results.


Subject(s)
Filtration/instrumentation , Lenses , Refractometry/instrumentation , Computer-Aided Design , Equipment Design , Equipment Failure Analysis , Light , Reproducibility of Results , Scattering, Radiation , Sensitivity and Specificity
14.
Arch Ophthalmol ; 127(2): 146-52, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19204231

ABSTRACT

OBJECTIVE: To assess the comparative effectiveness and cost-effectiveness (cost-utility) of a 0.05% emulsion of topical cyclosporine (Restasis; Allergan Inc, Irvine, California) for the treatment of moderate to severe dry eye syndrome that is unresponsive to conventional therapy. METHODS: Data from 2 multicenter, randomized, clinical trials and Food and Drug Administration files for topical cyclosporine, 0.05%, emulsion were used in Center for Value-Based Medicine analyses. Analyses included value-based medicine as a comparative effectiveness analysis and average cost-utility analysis using societal and third-party insurer cost perspectives. MAIN OUTCOME MEASURES: Outcome measures of comparative effectiveness were quality-adjusted life-year (QALY) gain and percentage of improvement in quality of life, and for cost-effectiveness were cost-utility ratio (CUR) using dollars per QALY. RESULTS: Topical cyclosporine, 0.05%, confers a value gain (comparative effectiveness) of 0.0319 QALY per year compared with topical lubricant therapy, a 4.3% improvement in quality of life for the average patient with moderate to severe dry eye syndrome that is unresponsive to conventional lubricant therapy. The societal perspective incremental CUR for cyclosporine over vehicle therapy is $34,953 per QALY and the societal perspective average CUR is $11,199 per QALY. The third-party-insurer incremental CUR is $37,179 per QALY, while the third-party-insurer perspective average CUR is $34,343 per QALY. CONCLUSIONS: Topical cyclosporine emulsion, 0.05%, confers considerable patient value and is a cost-effective therapy for moderate to severe dry eye syndrome that is unresponsive to conventional therapy.


Subject(s)
Cyclosporine/economics , Dry Eye Syndromes/economics , Evidence-Based Medicine , Immunosuppressive Agents/economics , Administration, Topical , Cost of Illness , Cost-Benefit Analysis , Cyclosporine/administration & dosage , Cyclosporine/adverse effects , Dry Eye Syndromes/drug therapy , Emulsions , Health Care Costs , Humans , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/adverse effects , Insurance, Health, Reimbursement , Life Expectancy , Quality of Life , Quality-Adjusted Life Years , Treatment Outcome
15.
Curr Opin Ophthalmol ; 17(3): 257-66, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16794438

ABSTRACT

PURPOSE OF REVIEW: The quality-of-life loss and the financial consequences associated with age-related macular degeneration are assessed. RECENT FINDINGS: The quality-of-life loss associated with macular degeneration is markedly underestimated by the general public, nonophthalmic physicians, and ophthalmologists who treat patients with this condition. Mild age-related macular degeneration causes a 17% decrement in the quality of life of the average patient, similar to that encountered with moderate cardiac angina or symptomatic human immunodeficiency virus syndrome. Moderate age-related macular degeneration causes a 40% decrease in the average patient's quality of life, similar to that associated with severe cardiac angina or renal dialysis. Very severe age-related macular degeneration causes a large 63% decrease in the average patient's quality of life, similar to that encountered with end-stage prostatic cancer or a catastrophic stroke that leaves a person bedridden, incontinent and requiring constant nursing care. The return on investment is high for both treatment with current age-related macular degeneration therapies and the research costs invested in the development of age-related macular degeneration treatment modalities. SUMMARY: Age-related macular degeneration is a major public health problem that has a devastating effect upon patients and marked adverse financial consequences for the economy.


Subject(s)
Cost of Illness , Cost-Benefit Analysis , Macular Degeneration/economics , Quality of Life , Evidence-Based Medicine , Health Care Costs , Humans
16.
Can J Ophthalmol ; 40(3): 277-87, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15947797

ABSTRACT

It can be estimated that 17,100 new cases of neovascular (wet) AMD and 180,000 new cases of geographic-atrophy (dry) AMD occur in Canada annually. In addition to having a devastating effect on patients' lives, the condition causes significant adverse consequences for the economy. The deleterious effect of AMD on quality of life is markedly underestimated by ophthalmologists who treat patients with AMD, by non-ophthalmic physicians and by the public. In fact, patients with different degrees of severity of AMD have a perceived impairment of their quality of life that is 96% to 750% greater than the impairment estimated by treating ophthalmologists. Mild AMD causes a 17% decrease in the quality of life of the average patient, a decrease similar to that encountered with symptomatic human immunodeficiency virus infection or moderate cardiac angina. Moderate AMD produces a 40% decrease in quality of life, a decrease similar to that associated with permanent renal dialysis or severe cardiac angina. Very severe AMD causes a 63% decrement in quality of life, a decrease similar to that encountered with advanced prostatic cancer with uncontrollable pain or a severe stroke that leaves a person bedridden, incontinent and requiring constant nursing care. The adverse economic consequences of AMD include an annual $2.6 billion negative impact on Canada's gross domestic product. The return on investment is high for both current AMD therapies and research into new treatment modalities.


Subject(s)
Evidence-Based Medicine/economics , Health Care Costs/trends , Macular Degeneration/economics , Canada/epidemiology , Costs and Cost Analysis , Humans , Incidence , Macular Degeneration/epidemiology , Macular Degeneration/therapy
17.
Trans Am Ophthalmol Soc ; 103: 173-84; discussion 184-6, 2005.
Article in English | MEDLINE | ID: mdl-17057801

ABSTRACT

PURPOSE: To assess the quality-of-life loss and the macroeconomic financial consequences associated with age-related macular degeneration (ARMD). METHODS: Time tradeoff utility analysis was performed to assess the quality-of-life diminution caused by ARMD (both dry and neovascular) in cohorts consisting of (1) patients with ARMD, (2) ophthalmologists asked to assume they had various degrees of severity of ARMD, (3) healthcare providers asked to assume they had various degrees of severity of ARMD, and (4) participants from the general community asked to assume they had various degrees of severity of ARMD. ARMD was classified according to vision in the better-seeing eye as (1) mild: 20/20 to 20/40, (2) moderate: 20/50 to 20/100, (3) severe: < or = 20/200, or (4) very severe: < or = 20/800. RESULTS: Mild ARMD caused a 17% decrement in the quality of life of the average patient, similar to that encountered with moderate cardiac angina or symptomatic human immunodeficiency virus syndrome. Moderate ARMD caused a 32% decrease in the average patient's quality of life, similar to that associated with severe cardiac angina or a fractured hip. Severe ARMD caused a 53% decrease in quality, more than that of dialysis, and very severe ARMD caused a 60% decrease in the average ARMD patient's quality of life, similar to that encountered with end-stage prostate cancer or a catastrophic stroke that leaves a person bedridden, incontinent, and requiring constant nursing care. Patients with varying degrees of severity of ARMD were found to have quality-of-life impairment ranging from 96% to 750% greater than that estimated by treating ophthalmologists for the same condition. An economic analysis based upon losses to the gross domestic product suggests that ARMD has approximately a $30 billion annual negative impact. The return on investment is therefore potentially high for both treatment with current ARMD therapies and the research costs invested in the development of new ARMD treatment modalities. CONCLUSIONS: ARMD is a major public health problem that has a devastating effect upon patients and marked adverse financial consequences for the economy.


Subject(s)
Cost of Illness , Economics, Medical , Evidence-Based Medicine , Longevity , Macular Degeneration/physiopathology , Macular Degeneration/therapy , Quality of Life , Adult , Aged , Aged, 80 and over , Attitude of Health Personnel , Cohort Studies , Humans , Incidence , Macular Degeneration/epidemiology , Middle Aged , Ophthalmology , Prevalence , Severity of Illness Index , United States/epidemiology
SELECTION OF CITATIONS
SEARCH DETAIL
...