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1.
Epilepsia Open ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38790148

RESUMO

OBJECTIVE: In epilepsy, early diagnosis, accurate determination of epilepsy type, proper selection of antiseizure medication, and monitoring are all essential. However, despite recent therapeutic advances and conceptual reconsiderations in the classification and management of epilepsy, serious gaps are still encountered in day-to-day practice in Egypt as well as several other resource-limited countries. Premature mortality, poor quality of life, socio-economic burden, cognitive problems, poor treatment outcomes, and comorbidities are major challenges that require urgent actions to be implemented at all levels. In recognition of this, a group of Egyptian epilepsy experts met through a series of consecutive meetings to specify the main concepts concerning the diagnosis and management of epilepsy, with the ultimate goal of establishing a nationwide Egyptian consensus. METHODS: The consensus was developed through a modified Delphi methodology. A thorough review of the most recent relevant literature and international guidelines was performed to evaluate their applicability to the Egyptian situation. Afterward, several remote and live rounds were scheduled to reach a final agreement for all listed statements. RESULTS: Of 278 statements reviewed in the first round, 256 achieved ≥80% agreement. Live discussion and refinement of the 22 statements that did not reach consensus during the first round took place, followed by final live voting then consensus was achieved for all remaining statements. SIGNIFICANCE: With the implementation of these unified recommendations, we believe this will bring about substantial improvements in both the quality of care and treatment outcomes for persons with epilepsy in Egypt. PLAIN LANGUAGE SUMMARY: This work represents the efforts of a group of medical experts to reach an agreement on the best medical practice related to people with epilepsy based on previously published recommendations while taking into consideration applicable options in resource-limited countries. The publication of this document is expected to minimize many malpractice issues and pave the way for better healthcare services on both individual and governmental levels.

2.
Biomed Eng Online ; 23(1): 48, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760808

RESUMO

Monitoring of ingestive activities is critically important for managing the health and wellness of individuals with various health conditions, including the elderly, diabetics, and individuals seeking better weight control. Monitoring swallowing events can be an ideal surrogate for developing streamlined methods for effective monitoring and quantification of eating or drinking events. Swallowing is an essential process for maintaining life. This seemingly simple process is the result of coordinated actions of several muscles and nerves in a complex fashion. In this study, we introduce automated methods for the detection and quantification of various eating and drinking activities. Wireless surface electromyography (sEMG) was used to detect chewing and swallowing from sEMG signals obtained from the sternocleidomastoid muscle, in addition to signals obtained from a wrist-mounted IMU sensor. A total of 4675 swallows were collected from 55 participants in the study. Multiple methods were employed to estimate bolus volumes in the case of fluid intake, including regression and classification models. Among the tested models, neural networks-based regression achieved an R2 of 0.88 and a root mean squared error of 0.2 (minimum bolus volume was 10 ml). Convolutional neural networks-based classification (when considering each bolus volume as a separate class) achieved an accuracy of over 99% using random cross-validation and around 66% using cross-subject validation. Multiple classification methods were also used for solid bolus type detection, including SVM and decision trees (DT), which achieved an accuracy above 99% with random validation and above 94% in cross-subject validation. Finally, regression models with both random and cross-subject validation were used for estimating the solid bolus volume with an R2 value that approached 1 and root mean squared error values as low as 0.00037 (minimum solid bolus weight was 3 gm). These reported results lay the foundation for a cost-effective and non-invasive method for monitoring swallowing activities which can be extremely beneficial in managing various chronic health conditions, such as diabetes and obesity.


Assuntos
Deglutição , Eletromiografia , Humanos , Deglutição/fisiologia , Masculino , Feminino , Automação , Processamento de Sinais Assistido por Computador , Adulto , Redes Neurais de Computação , Tecnologia sem Fio
3.
Biomedicines ; 12(4)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38672241

RESUMO

Gliomas are a type of brain tumor that requires accurate monitoring for progression following surgery. The Brain Tumor Reporting and Data System (BT-RADS) has emerged as a potential tool for improving diagnostic accuracy and reducing the need for repeated operations. This prospective multicenter study aimed to evaluate the diagnostic accuracy and reliability of BT-RADS in predicting tumor progression (TP) in postoperative glioma patients and evaluate its acceptance in clinical practice. The study enrolled patients with a history of partial or complete resection of high-grade glioma. All patients underwent two consecutive follow-up brain MRI examinations. Five neuroradiologists independently evaluated the MRI examinations using the BT-RADS. The diagnostic accuracy of the BT-RADS for predicting TP was calculated using histopathology after reoperation and clinical and imaging follow-up as reference standards. Reliability based on inter-reader agreement (IRA) was assessed using kappa statistics. Reader acceptance was evaluated using a short survey. The final analysis included 73 patients (male, 67.1%; female, 32.9%; mean age, 43.2 ± 12.9 years; age range, 31-67 years); 47.9% showed TP, and 52.1% showed no TP. According to readers, TP was observed in 25-41.7% of BT-3a, 61.5-88.9% of BT-3b, 75-90.9% of BT-3c, and 91.7-100% of BT-RADS-4. Considering >BT-RADS-3a as a cutoff value for TP, the sensitivity, specificity, and accuracy of the BT-RADS were 68.6-85.7%, 84.2-92.1%, and 78.1-86.3%, respectively, according to the reader. The overall IRA was good (κ = 0.75) for the final BT-RADS classification and very good for detecting new lesions (κ = 0.89). The readers completely agreed with the statement "the application of the BT-RADS should be encouraged" (score = 25). The BT-RADS has good diagnostic accuracy and reliability for predicting TP in postoperative glioma patients. However, BT-RADS 3 needs further improvements to increase its diagnostic accuracy.

4.
Clin Neurol Neurosurg ; 233: 107946, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37639829

RESUMO

OBJECTIVES: The international league against epilepsy (ILAE) recommended the harmonized neuroimaging of epilepsy structural sequences (HARNESS-MRI) to improve the detection of epileptogenic lesions in patients with focal drug-resistant epilepsy (DRE). The application of this protocol is still limited in low-resource countries, mainly due to apparent high costs. We aimed to evaluate the cost-effectiveness of the HARNESS-MRI protocol in Egypt and highlighted our experience. METHODS: Patients diagnosed with focal DRE at Cairo University epilepsy clinic underwent both conventional MRI (c-MRI) and HARNESS-MRI. Electro-clinical data were collected and analyzed. After the radiologists' initial diagnosis, a multidisciplinary team re-evaluated the MRI. Lesion detection rate and cost for detecting an extra lesion by HARNESS-MRI protocol were calculated. RESULTS: The study included 230 patients with focal DRE (146, 62% males and 91, 38% females), with a mean age of 20.5 years. Epileptogenic lesions detected by c-MRI and HARNESS-MRI before and after the board meeting were 40, 106, and 131 lesions, respectively (P < 0.001). Sixty-nine percent of the lesions detected by HARNESS-MRI were missed on c-MRI; most commonly were mesial temporal sclerosis (MTS) and Malformations of cortical development (MCDs). Thirty-seven MTS and 32 MCDs were detected with HARNESS-MRI, compared to only 6 and 3, respectively, detected on c-MRI (P < 0.001). HARNESS-MR protocol is more cost-effective than c-MRI in detecting MRI lesions; it can save about 42$ for detecting an extra lesion in MRI. CONCLUSION: The HARNESS-MRI protocol was cost-effective and highly recommended even in limited-resource countries for patients with focal DRE.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Esclerose Hipocampal , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Análise Custo-Benefício , Egito , Imageamento por Ressonância Magnética/métodos , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia/diagnóstico por imagem
5.
Surg Neurol Int ; 14: 240, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560561

RESUMO

Background: Multidisciplinary pre-surgical evaluation is vital for epilepsy surgery decision and outcomes. Resective epilepsy surgery with assisted monitoring is currently a standard treatment for focal drug resistant epilepsy (DRE). In resource-limited countries, lack of epilepsy surgery center is a huge challenge. We presented and illustrated how to create a multidisciplinary protocol with resource-limited settings in a developing country and epilepsy surgery outcome using brain mapping and monitoring techniques for ensuring satisfactory resection. Methods: We created multicentric incomplete but complementary units covering all epilepsy-related sub-specialties and covering a wide geographical area in our country. Then, we conducted a prospective and multicentric study with low resource settings on patients with focal DRE, who underwent resective epilepsy surgery and were followed up for at least 12 months and were evaluated for postoperative seizure outcome and complications if present. Preoperative comprehensive clinical, neurophysiological, neuropsychological, and radiological evaluations were performed by multidisciplinary epilepsy team. Intraoperative brain mapping including awake craniotomy and direct stimulation techniques, neurophysiological monitoring, and electrocorticography was carried out during surgical resection. Results: The study included 47 patients (18 females and 29 males) with mean age 20.4 ± 10.02 years. Twenty-two (46.8%) patients were temporal epilepsy while 25 (53.2%) were extra-temporal epilepsy. The epilepsy surgery outcome at the last follow up was Engel Class I (seizure free) in 35 (74.5%), Class II (almost seizure free) in 8 (17%), Class III (worthwhile improvement) in 3 (6.4%), and Class IV (no worthwhile improvement) in 1 patient (2.1%). Conclusion: With low resource settings and lack of single fully equipped epilepsy center, favorable outcomes after resective surgery in patients with focal DRE could be achieved using careful presurgical multidisciplinary selection, especially with using intraoperative brain mapping and electrocorticography techniques.

6.
Neurosurgery ; 93(2): 274-291, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36961213

RESUMO

BACKGROUND: Awake craniotomy (AC) is a common neurosurgical procedure for the resection of lesions in eloquent brain areas, which has the advantage of avoiding general anesthesia to reduce associated complications and costs. A significant resource limitation in low- and middle-income countries constrains the usage of AC. OBJECTIVE: To review the published literature on AC in African countries, identify challenges, and propose pragmatic solutions by practicing neurosurgeons in Africa. METHODS: We conducted a scoping review under Preferred Reporting Items for Systematic Reviews and Meta-Analysis-Scoping Review guidelines across 3 databases (PubMed, Scopus, and Web of Science). English articles investigating AC in Africa were included. RESULTS: Nineteen studies consisting of 396 patients were included. Egypt was the most represented country with 8 studies (42.1%), followed by Nigeria with 6 records (31.6%). Glioma was the most common lesion type, corresponding to 120 of 396 patients (30.3%), followed by epilepsy in 71 patients (17.9%). Awake-awake-awake was the most common protocol used in 7 studies (36.8%). Sixteen studies (84.2%) contained adult patients. The youngest reported AC patient was 11 years old, whereas the oldest one was 92. Nine studies (47.4%) reported infrastructure limitations for performing AC, including the lack of funding, intraoperative monitoring equipment, imaging, medications, and limited human resources. CONCLUSION: Despite many constraints, AC is being safely performed in low-resource settings. International collaborations among centers are a move forward, but adequate resources and management are essential to make AC an accessible procedure in many more African neurosurgical centers.


Assuntos
Neoplasias Encefálicas , Glioma , Adulto , Criança , Humanos , África/epidemiologia , Neoplasias Encefálicas/cirurgia , Craniotomia/métodos , Glioma/cirurgia , Vigília , Idoso de 80 Anos ou mais
7.
Surg Neurol Int ; 12: 117, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33880222

RESUMO

BACKGROUND: Intraoperative mapping techniques maximize safety and efficacy during perirolandic glioma resection but may induce seizures and limit the procedure. We aim to report the incidence and predictors of stimulation-induced seizures during mapping either patient is awake or under general anesthesia (GA). METHODS: Retrospective analysis of 64 patients (40 awake and 24 GA) with perirolandic glioma underwent resection using intraoperative mapping techniques between 2014 and 2019. Preoperative data, operative details, postoperative neurological status, and extent of resection (EOR) were analyzed. Predictors of intraoperative seizures were assessed. RESULTS: The mean cortical and subcortical stimulation intensities needed to evoke motor responses were significantly lower in awake cases than in GA patients (4.9 ± 0.42 vs. 8.9 ± 1.2 mA) and (8.3 ± 0.62 vs. 12.1 ± 1.1 mA), respectively (P = 0.01). Incidence of intraoperative seizures was lower but statistically non-significant in awake cases (10% vs. 12.5%) (P = 0.76). Preoperative multiple antiepileptic drugs (AEDs) (P = 0.03) and low-grade glioma (P = 0.04) were statistically significant predictors for intraoperative seizures. Mean EOR in awake cases was 92.03% and 90.05% in GA cases (P = 0.23). Postoperative deficits were permanent after 3 months only in 5% of awake patients versus 8.3% of GA group (P = 0.59). CONCLUSION: Awake craniotomy with intraoperative mapping can be done safely for perirolandic gliomas with lower but statistically nonsignificant incidence of intraoperative seizures and this could be attributed to statistically significant lower stimulation intensities required for mapping. Preoperative multiple AEDs and low-grade glioma are significant predictors for intraoperative seizures.

8.
J Obstet Gynaecol Res ; 46(11): 2375-2382, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32885585

RESUMO

AIM: To evaluate the effect of vitamin E on ovulation and pregnancy in women with clomiphene citrate (CC)-resistant polycystic ovary syndrome (PCOS). METHODS: A prospective, randomized, controlled, open label study was conducted on women with CC-resistant PCOS. Patients were randomized, to either control group (n = 30), who received metformin 500 mg thrice daily, in addition to 150 mg/day CC for 5 days starting from day 3 of menstruation for three menstruation cycles, or vitamin E group (n = 30) who received vitamin E 1500 IU/day for the whole study period in addition to metformin and CC with the same previous regimen. The primary outcome was cumulative ovulation rate, while secondary outcomes were pregnancy rate, serum midluteal progesterone, mean follicular diameter, number of dominant follicles and endometrial thickness. RESULTS: Ovulation was reported in 57 (64.8%) of 88 cycles in the control group and 63 (73.3%) of 86 cycles in the vitamin E group (P = 0.227), while pregnancy was reported in 4 (4.5%) of 88 cycles in the control group and 6 (7%) of 86 cycles in the vitamin E group (P = 0.491).There were nonsignificant differences between groups regarding serum midluteal progesterone, number of dominant follicles and mean follicular diameter. Endometrial thickness was significantly higher in the vitamin E group compared to the control group. CONCLUSION: The findings of this trial do not support the hypothesis that vitamin E may increase the ovulation and pregnancy rates in women with clomiphene citrate-resistant PCOS.


Assuntos
Infertilidade Feminina , Síndrome do Ovário Policístico , Clomifeno , Suplementos Nutricionais , Feminino , Fertilidade , Fármacos para a Fertilidade Feminina , Humanos , Infertilidade Feminina/tratamento farmacológico , Indução da Ovulação , Síndrome do Ovário Policístico/tratamento farmacológico , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Vitamina E
9.
Heart Lung Circ ; 29(10): 1554-1560, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32199778

RESUMO

BACKGROUND: Surgical repair of concomitant functional moderate tricuspid valve (TV) regurgitation at the time of mitral valve (MV) surgery remains controversial. AIM: The objective of this study was to evaluate the outcomes of concomitant repair of functional moderate tricuspid regurgitation (TR) during MV surgery for rheumatic valve disease. METHOD: From 1998 to 2016, 1,240 patients had rheumatic MV disease associated with moderate functional TR: 974 patients had MV surgery and concomitant TV repair (group 1) and 266 patients had MV surgery alone (group 2). Study endpoints were operative outcomes, rehospitalisation for congestive heart failure (CHF), and TV reintervention. Propensity score matching identified 192 well-matched pairs for outcomes comparison. RESULTS: Patients who had concomitant TV repair were younger (p=0.02) and there were fewer diabetics (p=0.015). In matched patients, low cardiac output was significantly higher in group 2 (p=0.044) and there was no difference in ventilation time, intensive care unit stay, cardiopulmonary bypass, and ischaemic times (p=0.480, p=0.797, p=0.232, and p=0.550, respectively) between groups. Patients in group 2 required more TV reintervention (1 vs 35 in group 1 and 2, respectively; p=0.004) and rehospitalisation for CHF (5 vs 40 in group 1 and 2, respectively; p<0.001). CONCLUSIONS: Concomitant TV repair for moderate TR in patients undergoing rheumatic MV surgery was not associated with increased operative risk. Postoperative low cardiac output syndrome and the risk of late TV reinterventions and rehospitalisation for CHF were lower with TV repair. Concomitant repair of the moderate TV regurgitation maybe beneficial for patients undergoing rheumatic MV surgery.


Assuntos
Anuloplastia da Valva Cardíaca/métodos , Valva Mitral/cirurgia , Pontuação de Propensão , Cardiopatia Reumática/cirurgia , Insuficiência da Valva Tricúspide/cirurgia , Valva Tricúspide/cirurgia , Função Ventricular/fisiologia , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Cardiopatia Reumática/complicações , Fatores de Risco , Resultado do Tratamento , Insuficiência da Valva Tricúspide/complicações , Insuficiência da Valva Tricúspide/fisiopatologia
10.
Heliyon ; 5(1): e01168, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30775569

RESUMO

The effect of soil-applied Allium crop products on the Stromatinia cepivora viability and the incidence of white rot in subsequent onion and garlic crops were evaluated in this work. The tested products were onion powder, garlic powder, onion oil, garlic oil and Allium waste (onion and garlic) that are described as sclerotial germination stimulants. Under in vitro conditions, data revealed that more than 80% of the sclerotia died in the soil treated with sclerotial germination stimulants. Under greenhouse conditions, soil-artificially infested with sclerotia of S. cepivora and treated with sclerotial germination stimulants for 6-months before cultivation, significantly reduced the incidence of white rot on onion and garlic. Onion oil, garlic oil and Allium waste were the most effective treatments, decreasing disease incidence by 78.6% in onion and 80.0% in garlic. Under field conditions, sclerotial germination stimulants were incorporated into the soil in commercial fields naturally infested with S. cepivora. Two fields were chosen based on differential sclerotial density. Within 6 months after treatment, more than 70% of the sclerotia died in the plots treated with sclerotial germination stimulants. In subsequent onion and garlic crops planted approximately one year after soil treatment, sclerotial germination stimulants were more effective than the control in reducing white rot symptoms coupled with low inoculum density (45.9 sclerotia/kg of soil). Reduction of white rot disease was accompanied by increased of growth and bulbs yield of onion and garlic plants. Despite the efficacy of sclerotial germination stimulants to reduce populations of viable sclerotia in soil with a high inoculum density (594.7 sclerotia/kg of soil), the pathogen caused substantial white rot and yield losses in subsequent onion and garlic crops planted approximately one year after soil treatment.

11.
J Adv Res ; 7(3): 327-35, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27222738

RESUMO

Dracaena sanderiana, of the family Liliaceae, is among the ornamental plants most frequently imported into Egypt. Typical anthracnose symptoms were observed on the stems of imported D. sanderiana samples. The pathogen was isolated, demonstrated to be pathogenic based on Koch's rule and identified as Colletotrichum dracaenophilum. The optimum temperature for its growth ranges from 25 to 30 °C, maintained for 8 days. Kemazed 50% wettable powder (WP) was the most effective fungicide against the pathogen, as no fungal growth was observed over 100 ppm. The biocontrol agents Trichoderma harzianum and Trichoderma viride followed by Bacillus subtilis and Bacillus pumilus caused the highest reduction in fungal growth. To the best of our knowledge, this report describes the first time that this pathogen was observed on D. sanderiana in Egypt.

12.
World Neurosurg ; 87: 439-45, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26585720

RESUMO

AIM: We hypothesize that re-do craniotomy for recurrent grade IV glioblastomas improves survival while preserving outcome in selected patients. METHODS: A retrospective analysis was conducted of 141 patients, from a prospectively collected database from 2004-2014, with grade IV glioblastomas who underwent craniotomy and excision. Sixty-five patients were included in our analysis. Twenty patients underwent re-do craniotomy at recurrence and were compared with 45 patients who received nonsurgical therapy for recurrences. Primary end point was overall survival from time of diagnosis. Demographic and disease factors were analyzed using Cox regression analysis for significance. RESULTS: The median survival for those with re-do craniotomy was 25.4 months compared with 11.6 months (P < 0.001) in the group that underwent nonsurgical therapy. The mean age for this group was 53.5 years. This group had a higher postsurgical/treatment median Karnofsky performance scale (KPS) of 80 compared with 60 (P < 0.001) showing better functional outcome. A Cox regression analysis of factors determined that age, KPS at recurrence, extent of resection at initial surgery and re-do craniotomy were significant for positive outcomes. CONCLUSION: Our results show that in a select group of patients with recurrent grade IV glioblastomas, repeated excision, aiming for gross total resection where safely possible, has significant survival benefit without severely compromising functionality and should be considered.


Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Craniotomia , Glioblastoma/patologia , Glioblastoma/cirurgia , Recidiva Local de Neoplasia/cirurgia , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Craniotomia/métodos , Bases de Dados Factuais , Determinação de Ponto Final , Feminino , Glioblastoma/mortalidade , Glioblastoma/terapia , Humanos , Estimativa de Kaplan-Meier , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Modelos de Riscos Proporcionais , Reoperação , Estudos Retrospectivos , Singapura , Análise de Sobrevida
13.
J Clin Neurosci ; 22(11): 1827-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26249245

RESUMO

We report our institutional experience using an electromagnetic navigation system, without rigid head fixation, for awake craniotomy patients. The StealthStation® S7 AxiEM™ navigation system (Medtronic, Inc.) was used for this technique. Detailed preoperative clinical and neuropsychological evaluations, patient education and contrast-enhanced MRI (thickness 1.5mm) were performed for each patient. The AxiEM Mobile Emitter was typically placed in a holder, which was mounted to the operating room table, and a non-invasive patient tracker was used as the patient reference device. A monitored conscious sedation technique was used in all awake craniotomy patients, and the AxiEM Navigation Pointer was used for navigation during the procedure. This offers the same accuracy as optical navigation, but without head pin fixation or interference with intraoperative neurophysiological techniques and surgical instruments. The application of the electromagnetic neuronavigation technology without rigid head fixation during an awake craniotomy is accurate, and offers superior patient comfort. It is recommended as an effective adjunctive technique for the conduct of awake surgery.


Assuntos
Craniotomia/instrumentação , Craniotomia/métodos , Neuronavegação/instrumentação , Neuronavegação/métodos , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Vigília
15.
Artigo em Inglês | MEDLINE | ID: mdl-23366968

RESUMO

We propose a new sleep quality measure that assesses the sleep restorative gain of a polysomnography sleep record. In this preliminary investigation, we derive this new measure from manually scored sleep hypnograms. We compare the proposed measure to classical sleep indices such as TST, SE, and ArI, and demonstrate its self-consistency and degree of correlation with these measures. Using 47 sleep records from publicly available sleep databases, we graphically and quantitatively demonstrate the effectiveness of the proposed measure in summarizing the hypnogram of a sleep record.


Assuntos
Algoritmos , Diagnóstico por Computador/métodos , Polissonografia/métodos , Sono/fisiologia , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Artigo em Inglês | MEDLINE | ID: mdl-19162989

RESUMO

We present a new adaptive system for automated sleep staging. The proposed system relies on each subject's own data for self-training. Conventional automatic sleep staging algorithms are either rule based, which typically fail to accurately model the complex nature of sleep signals, or numerical methods that use multi-patient training schemes, which suffer from inaccuracies caused by inherent inter-patient variability. The proposed system employs two stages. The first stage is a rule based reasoning engine that can be tuned conservatively to decrease or eliminate false positives, generating just enough samples to train the second stage, which is comprised of a neural network classifier. Results show that this hybrid approach provides an adaptive training scheme that performs more accurately compared to one of the popular commercially available systems.


Assuntos
Algoritmos , Redes Neurais de Computação , Fases do Sono/fisiologia , Adulto , Inteligência Artificial , Engenharia Biomédica , Eletroencefalografia/estatística & dados numéricos , Eletroculografia/estatística & dados numéricos , Feminino , Humanos , Masculino , Processamento de Sinais Assistido por Computador , Sono REM/fisiologia
17.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 5948-51, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17945923

RESUMO

We present the hardware design of an FPGA-based portable device for home screening of sleep apnea syndromes. The device is simple to use, inexpensive, and uses only three signals, namely the nasal air flow and the thorax and abdomen effort signals. The device hardware stores data of overnight sleep on a Secure Digital card. At the clinic, the sleep specialist reads in the stored data and uses an algorithm for the detection and classification of sleep apnea. The device is fairly low-cost and may help spread the ability to diagnose more cases of sleep apnea. Most sleep apnea cases currently go undiagnosed because of cost and practicality limitations of overnight polysomnography at sleep labs.


Assuntos
Desenho de Equipamento , Polissonografia/instrumentação , Síndromes da Apneia do Sono/diagnóstico , Apneia Obstrutiva do Sono/diagnóstico , Fontes de Energia Elétrica , Fenômenos Eletromagnéticos , Humanos , Movimento , Oximetria , Polissonografia/economia , Polissonografia/métodos , Reprodutibilidade dos Testes , Respiração , Sensibilidade e Especificidade , Sono , Software , Interface Usuário-Computador
18.
Conf Proc IEEE Eng Med Biol Soc ; Suppl: 6781-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17959511

RESUMO

This paper attempts to develop a better understanding of the high pulse repetition frequency (HPRF)mode used in ultrasound systems with pulsed wave Doppler capability. It provides both intuition and mathematical analysis to help answer the fundamental question of whether the HPRF mode is feasible at any given depth using a visualization tool called Baker diagrams. The tool provides a better understanding of many of the limitations associated with the HPRF Doppler mode.


Assuntos
Efeito Doppler , Processamento de Sinais Assistido por Computador , Ultrassom
19.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 6124-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281661

RESUMO

We report an adaptive diagnostic system for the classification of breathing events for the purpose of detecting sleep apnea syndromes. The system employs two classification engines used in series. The first engine is fuzzy logic-based and generates one of three outcomes for each breathing event: normal, abnormal, and not-sure. The second classification engine is based on a center of gravity engine which is trained using the normal and abnormal events, generated by the first engine, and is specifically designed for sorting out the not-sure events. The fuzzy logic engine can be tuned very conservatively to reduce or eliminate the chance of error at the first stage. Since the second engine is trained adaptively using normal and abnormal data of the same patient, its accuracy is generally better than relying on multi-patient training approaches. The two-step, adaptive nature of the system allows for high accuracy and lends itself well for practical implementation.

20.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 6132-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281663

RESUMO

We have previously reported a system suitable for detection and classification of sleep apnea syndromes. This paper reports the results of the clinical evaluation of the proposed system. In the current implementation, the system uses breathing signals: nasal flow, thorax movement, and abdomen movement. The detection part of the system uses only the nasal flow signal to detect apnea employing two engines used in series. It then feeds segments labeled as abnormal to the classification part of the system, which uses the center of gravity of each segment to determine the type of abnormality: obstructive, central or hypopnea. In comparison to other systems, this implementation can be shown to be simpler and more accurate. When the low implementation cost is taken into consideration, the proposed system has a substantial potential for being used as a screening device.

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