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1.
Math Biosci Eng ; 18(2): 1550-1572, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33757198

RESUMO

Gliomas are a type of central nervous system (CNS) tumor that accounts for the most of malignant brain tumors. The World Health Organization (WHO) divides gliomas into four grades based on the degree of malignancy. Gliomas of grades I-II are considered low-grade gliomas (LGGs), whereas gliomas of grades III-IV are termed high-grade gliomas (HGGs). Accurate classification of HGGs and LGGs prior to malignant transformation plays a crucial role in treatment planning. Magnetic resonance imaging (MRI) is the cornerstone for glioma diagnosis. However, examination of MRI data is a time-consuming process and error prone due to human intervention. In this study we introduced a custom convolutional neural network (CNN) based deep learning model trained from scratch and compared the performance with pretrained AlexNet, GoogLeNet and SqueezeNet through transfer learning for an effective glioma grade prediction. We trained and tested the models based on pathology-proven 104 clinical cases with glioma (50 LGGs, 54 HGGs). A combination of data augmentation techniques was used to expand the training data. Five-fold cross-validation was applied to evaluate the performance of each model. We compared the models in terms of averaged values of sensitivity, specificity, F1 score, accuracy, and area under the receiver operating characteristic curve (AUC). According to the experimental results, our custom-design deep CNN model achieved comparable or even better performance than the pretrained models. Sensitivity, specificity, F1 score, accuracy and AUC values of the custom model were 0.980, 0.963, 0.970, 0.971 and 0.989, respectively. GoogLeNet showed better performance than AlexNet and SqueezeNet in terms of accuracy and AUC with a sensitivity, specificity, F1 score, accuracy, and AUC values of 0.980, 0.889, 0.933, 0.933, and 0.987, respectively. AlexNet yielded a sensitivity, specificity, F1 score, accuracy, and AUC values of 0.940, 0.907, 0.922, 0.923 and 0.970, respectively. As for SqueezeNet, the sensitivity, specificity, F1 score, accuracy, and AUC values were 0.920, 0.870, 0.893, 0.894, and 0.975, respectively. The results have shown the effectiveness and robustness of the proposed custom model in classifying gliomas into LGG and HGG. The findings suggest that the deep CNNs and transfer learning approaches can be very useful to solve classification problems in the medical domain.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Curva ROC
2.
Exp Aging Res ; 47(4): 373-385, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33719928

RESUMO

Background: This study aimed to compare the BMD status among the clinical subtypes of PD and healthy controls.Methods: Sixty patients with PD and 30 healthy age- and sex-matched controls were included in this study. The patients were divided into postural instability gait difficulty-dominant type (PIGDDT) group and tremor-dominant type (TDT) group based on the Unified Parkinson's Disease Rating Scale (UPDRS) score. BMD was measured using dual-energy X-ray absorptiometry scans in femoral and lumbar regions.Results: The T-scores in femoral and lumbar regions were similar in all groups. The prevalence of osteopenia was higher than the prevalence of osteoporosis in all three groups for femoral regions. The prevalence of osteoporosis in the intertrochanteric region and total femur in the PIGDDT group was higher than in the TDT group and controls. Our data showed a trend toward higher prevalence of osteoporosis in the PIGDDT group.Conclusion: The prevalence of osteopenia and osteoporosis may differ between clinical subtypes of PD and healthy controls. Osteopenia is more common than osteoporosis for all groups. The patients with PIGDDT of PD tended to have higher prevalence of osteoporosis, even at early stages of disease, compared to those with TDT and healthy controls.


Assuntos
Osteoporose , Doença de Parkinson , Absorciometria de Fóton , Envelhecimento , Densidade Óssea , Humanos , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Doença de Parkinson/epidemiologia
3.
Turk Neurosurg ; 29(4): 555-563, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30900733

RESUMO

AIM: To compare the clinical and functional outcomes between combined anterior and posterior 2-segment spinal fusion and posterior 3-segment spinal fusion in patients with thoracolumbar (TL) burst fractures at risk for posttraumatic kyphosis without neurological deficit. MATERIAL AND METHODS: Twenty-seven patients with TL burst fracture, > 20° kyphosis and/or 50% collapse, and posterior ligament injury, but without neurological deficit, were randomly assigned into posterior and combined groups. Posterior treatment was 3-segment (1 level below, fractured level and 2 levels above) posterior spinal fusion. Combined treatment was including 1 cranial and 1 caudal levels posterior spinal fusion, followed by anterior corpectomy, cage, and bone grafting. Patients were followed-up for a mean duration of 117.7 ± 8.7 months (range, 98-132 months). At the final follow-up, the clinical and functional means of the groups were compared using degree of kyphosis, visual analogue scale (VAS), and Roland-Morris and Oswestry scores. RESULTS: Mean patient age was 38.5 ± 2.4 years (range: 18-68 years). Fourteen and 13 patients were treated with the combined and posterior approach, respectively. Age (40.0 ± 10.3 and 37.0 ± 14.2 years; p=0.519), sex (female/male, 3:10 and 5:9; p=0.385), mechanism of injury (p=0.513), fractured levels (p=0.185), type of fracture (p=0.293), degree of kyphosis at initial admission (p=0.616), collapse (p=0.155), canal narrowing (p=0.280), follow-up (p=0.076) and accompanied limb fracture (p=0.374) were similar between groups. Duration of hospital stay was similar between two groups (p=0.102). However, blood loss was higher in combined group (195 ml versus 358ml, p=0.003). A 14.2° correction was achieved in the posterior group and 16.9° in the combined group (p=0.61). Loss of correction at the last follow-up visit was 2.1° with a final kyphosis of 7.2° in the posterior group, and 1.2° with a final kyphosis of 5.5° in the combined group. The differences in the correction of kyphosis (p=0.616), postop kyphosis (p=0.756), loss of correction (p=0.141) and final kyphosis (p=0.085) between the treatment groups were not significant. At the last follow-up visit of the posterior and combined groups, the VAS (16.4 ± 14.8 vs. 17.6 ± 16.6; p=0.685), Roland-Morris (27.2 ± 27.3 vs. 29.6 ± 20.5; p=0.519), and Oswestry scores (15.0 ± 13.1 vs. 17.7 ± 11.5; p=0.302) were similar. CONCLUSION: Both treatment methods are similar in terms of clinical and functional outcomes.


Assuntos
Vértebras Lombares/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Fusão Vertebral/métodos , Vértebras Torácicas/cirurgia , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/lesões , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/lesões , Fatores de Tempo , Adulto Jovem
4.
Eur J Orthop Surg Traumatol ; 25(6): 1069-72, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25637049

RESUMO

INTRODUCTION: The purpose of this study was to compare two different modes of administration (telephone versus face to face) for Lysholm knee score (LKS) to test their multi-mode equivalence and reliability. MATERIALS AND METHODS: Two LKSs were obtained in 100 patients who underwent ACL reconstruction surgery. First LKS was completed through telephone interview, and second LKS, which was at least 2 weeks later, was completed face-to-face interview at the hospital. To analyze the test-retest reliability, the relative level of agreement between the two modes of administration for LKS was calculated using interclass correlation coefficient (ICC) in 95 % confidence interval. RESULTS: The mean LKS was 93.01 ± 9.12 (range 59-100) at telephone interview and 93.56 ± 7.93 (range 59-100) at face-to-face interview (p = 0.130). Both the total point and the each item's point were statistically similar (p < 0.05 for each item). The total score was same in 66 (66 %) subjects. The mean difference between two scoring was only 1.83 ± 3.14 points (range 0-15). However, eight (8 %) patients were assigned to different grading groups (excellent, good, fair, and poor). The overall LKS and the each item of the LKS had acceptable test-retest reliability [ICC = 0.954 (95 % CI 0.931-0.969)]. CONCLUSIONS: LKS can be reliably completed through telephone interview, which would provide accurate data similar to face-to-face interview. Researchers can design studies using telephone interview as a mode of administration for LKS or use mix-mode designs.


Assuntos
Reconstrução do Ligamento Cruzado Anterior/reabilitação , Artroscopia/reabilitação , Escore de Lysholm para Joelho/normas , Visita a Consultório Médico , Consulta Remota/normas , Telefone , Adolescente , Adulto , Coleta de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
5.
J Foot Ankle Surg ; 54(3): 517-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25441845

RESUMO

Myoclonic spasm of an amputated extremity can be problematic for amputees and requires recognition and understanding by surgeons encountering the phenomenon. In the present brief report, we describe the condition in a female amputee after below-the-knee amputation. Our aim is to increase awareness of this condition among foot and ankle surgeons.


Assuntos
Cotos de Amputação , Mioclonia/diagnóstico , Mioclonia/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Mioclonia/terapia
6.
Ulus Travma Acil Cerrahi Derg ; 19(2): 186-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23599208

RESUMO

Bilateral injuries of the sensory branch of the radial nerve (SBRN) usually occur as a result of tight-handcuff neuropathy. In this case we aimed to present bilateral isolated cut of SBRN resulting an injury mechanism that has not been reported in the literature previously. A male twenty-four years old, a worker in a glass factory, presented to our clinic. The dorsolateral skin of his wrists were cut by breaking of the glass as a result of occupational accident and was primarily sutured in a healthcare center. The patient sought additional care after a month because of lingering numbness and pain, and surgery was planned. During surgery, scar tissue and neuroma at the cut ends of SBRN were excised, and bilateral SBRN cuts were repaired. Four weeks after operation, mild sensory deficit on the dorsal side of bilateral thumbs, and left first web space and flexion limitation on the right wrist were detected. At the 3rd month postoperative, right wrist joint range of motion was full, and sensory deficits, and hyperesthesia were decreased. The SBRN elicits the sensory innervation of the thumb dorsum and its injury does not cause important functional deficit. However because of susceptibility of SBRN to develop painful neuroma, diagnosis, treatment and follow up of isolated SBRN injury would be worthwhile for prevention of possible painful neuropathy disturbing quality of life.


Assuntos
Acidentes de Trabalho , Traumatismos dos Nervos Periféricos/cirurgia , Nervo Radial/lesões , Nervo Radial/cirurgia , Humanos , Masculino , Traumatismos dos Nervos Periféricos/diagnóstico , Traumatismos dos Nervos Periféricos/patologia , Amplitude de Movimento Articular , Adulto Jovem
7.
Orthopedics ; 31(5): 453-8, 2008 05.
Artigo em Inglês | MEDLINE | ID: mdl-18522006

RESUMO

Subtrochanteric osteotomy of the femur using a bent dynamic compression plate is a simple, safe, and stable technique for correction of severe medial femoral torsion.


Assuntos
Placas Ósseas , Fêmur/cirurgia , Osteotomia/instrumentação , Anormalidade Torcional/cirurgia , Parafusos Ósseos , Criança , Feminino , Seguimentos , Humanos , Masculino , Osteotomia/métodos
8.
J Craniofac Surg ; 16(4): 719-22, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16077326

RESUMO

N-Butyl-2-cyanoacrylate (NB2C) is a synthetic tissue adhesive, and it has been used in many surgical procedures. This study was aimed at evaluating its efficacy in cleft palate repairs. Fifteen patients with soft palate and hard palate clefts had clefts repaired with the use of this synthetic adhesive. The ages at repair ranged from 11 months to 17 years, with an average of 2.4 years. Follow-up time ranged from 14 months to 24 months. No complications were found. The advantages of using NB2C were shorter operative time, more pushback gained, better hemostasis, early and well-tolerated feeding, tension-free closure, and better patient comfort. This study shows NB2C as a useful adjunctive material for affixing the mucoperiosteal flaps to the hard palate.


Assuntos
Cimentos Ósseos/uso terapêutico , Fissura Palatina/cirurgia , Embucrilato/análogos & derivados , Procedimentos Cirúrgicos Bucais/métodos , Retalhos Cirúrgicos , Adesivos Teciduais/uso terapêutico , Adolescente , Criança , Pré-Escolar , Embucrilato/uso terapêutico , Humanos , Lactente , Procedimentos de Cirurgia Plástica/métodos
9.
Ann Plast Surg ; 54(2): 207-10, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15655475

RESUMO

The surgical correction of craniofacial clefts is an extremely difficult field in pediatric plastic surgery. Facial clefts are rare entities that most plastic surgeons will rarely have to manage. Various surgical techniques devised by some authors for facial clefts have not still widely accepted. The bifid nose deformity is generally an indicator of Tessier No:0 clefts, with various degrees of skeletal problems. The nasal roof area is an important key point in determining the appropriate surgical technique for reconstruction. In this report, a case of Tessier No:0 with a moderate nasal bifidity and ours novel surgical repair technique combining oral and nasal incision are presented.


Assuntos
Nariz/anormalidades , Nariz/cirurgia , Criança , Anormalidades Craniofaciais/cirurgia , Feminino , Humanos , Osso Nasal/anormalidades , Osso Nasal/diagnóstico por imagem , Septo Nasal/anormalidades , Radiografia
13.
Int Orthop ; 27(4): 249-53, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12756502

RESUMO

The objective of this study was to present a simple, convenient, and reliable technique for the application of liquid nitrogen and to evaluate the effectiveness of curettage and cryosurgery. Between 1992 and 2002, 24 patients who had benign aggressive and low-grade malignant bone tumors were treated by curettage and cryosurgery. While cryosurgery was applied by the "direct pour" technique in the first seven patients, it was applied by the "pressurized spraying" technique in the others. Functional results were graded according to Enneking. The mean follow-up was 47 (range 9-131) months. There were no local recurrences. Three patients who underwent the direct pour technique developed partial skin necrosis. The functional results were excellent in 14 patients, good in six, and fair in four. When compared with previous reports on cryosurgery and its application techniques, we detected no tumor recurrence or complications, including soft-tissue injury, infection, and late fracture with liquid nitrogen applied by the pressurized spraying technique.


Assuntos
Neoplasias Ósseas/cirurgia , Criocirurgia/métodos , Adolescente , Adulto , Neoplasias Ósseas/patologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Nitrogênio , Resultado do Tratamento
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