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1.
Diagnostics (Basel) ; 13(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37046446

RESUMO

Brain tumors are nonlinear and present with variations in their size, form, and textural variation; this might make it difficult to diagnose them and perform surgical excision using magnetic resonance imaging (MRI) scans. The procedures that are currently available are conducted by radiologists, brain surgeons, and clinical specialists. Studying brain MRIs is laborious, error-prone, and time-consuming, but they nonetheless show high positional accuracy in the case of brain cells. The proposed convolutional neural network model, an existing blockchain-based method, is used to secure the network for the precise prediction of brain tumors, such as pituitary tumors, meningioma tumors, and glioma tumors. MRI scans of the brain are first put into pre-trained deep models after being normalized in a fixed dimension. These structures are altered at each layer, increasing their security and safety. To guard against potential layer deletions, modification attacks, and tempering, each layer has an additional block that stores specific information. Multiple blocks are used to store information, including blocks related to each layer, cloud ledger blocks kept in cloud storage, and ledger blocks connected to the network. Later, the features are retrieved, merged, and optimized utilizing a Genetic Algorithm and have attained a competitive performance compared with the state-of-the-art (SOTA) methods using different ML classifiers.

2.
Vascular ; 31(2): 199-210, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35435780

RESUMO

OBJECTIVES: By analyzing national Vascular Quality Initiative (VQI) data for patients undergoing open infrarenal abdominal aortic aneurysms (AAA) repair, we sought to better characterize the effects of different suprarenal clamping positions on postoperative outcomes. METHODS: We performed a retrospective analysis of a prospectively collected national VQI database for all open infrarenal AAA repairs performed between 2003 and 2017. Patients were initially divided into proximal (above 1 renal, above 2 renals, and supraceliac) and infrarenal clamp groups. Patients were then subdivided into those who underwent surgery between 2003-2010 and those who had surgery between 2011-2017. Univariate followed by multivariate analyses were done to compare the baseline characteristics, preoperative, intraoperative, and postoperative outcomes between the two groups. RESULTS: During the study period, 9068 open AAA repairs were recorded in the VQI; of these, 5043 met the inclusion criteria. Aortic clamp level was infrarenal in 59% (N = 2975), above 1 renal in 15% (N = 735), above both renals in 21% (N = 1053), and supraceliac in 5% (N = 280). The average age was 69 years, and males comprised 73% (N = 3701) of the cohort. The overall 30-day mortality for the entire study group was 2.7%. On univariate analysis, patients who underwent proximal clamping had significantly higher 30-day mortality than those undergoing infrarenal clamping (3.7 vs 2.0%, p < 0.001). After adjusting for preoperative and intraoperative variables, this difference became nonsignificant. On multivariate analysis, clamping above both renals or the celiac artery was associated with an increased occurrence of postoperative myocardial infarction (odds ratio = 1.44, p = 0.037 and odds ratio = 1.78, p = 0.023, respectively). All proximal clamp positions were associated with a significant increase in the incidence of AKI and renal failure requiring dialysis. There was no significant difference when looking at overall survival times comparing the suprarenal and infrarenal clamp position groups (p = 0.1). Patients who underwent surgery in the latter half of the study period had longer intraoperative renal ischemia time, increased in estimated blood loss, and longer total procedure time. CONCLUSIONS: Suprarenal clamping, at any level, was associated with an increased risk of AKI and renal replacement therapy. Clamping above both renal and celiac arteries was associated with increased cardiac morbidity. Perioperative and long-term mortality was unaffected by clamp level. Patients operating in the latter half of the study had increased estimated blood loss, renal ischemia time, and operative time, which may reflect decreased training in open AAA repair. During open AAA repair, the proximal clamp site should be chosen based on anatomic considerations and not a perceived perioperative mortality benefit. Proximal aortic clamping should always be performed at the safest, distal-most level to reduce cardiac morbidity and the risk of postoperative dialysis.


Assuntos
Injúria Renal Aguda , Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Masculino , Humanos , Idoso , Feminino , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/complicações , Estudos Retrospectivos , Resultado do Tratamento , Aorta Abdominal/cirurgia , Isquemia/cirurgia , Complicações Pós-Operatórias , Injúria Renal Aguda/etiologia , Fatores de Risco
3.
Sensors (Basel) ; 22(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35408415

RESUMO

Cancer is the deadliest disease among all the diseases and the main cause of human mortality. Several types of cancer sicken the human body and affect organs. Among all the types of cancer, stomach cancer is the most dangerous disease that spreads rapidly and needs to be diagnosed at an early stage. The early diagnosis of stomach cancer is essential to reduce the mortality rate. The manual diagnosis process is time-consuming, requires many tests, and the availability of an expert doctor. Therefore, automated techniques are required to diagnose stomach infections from endoscopic images. Many computerized techniques have been introduced in the literature but due to a few challenges (i.e., high similarity among the healthy and infected regions, irrelevant features extraction, and so on), there is much room to improve the accuracy and reduce the computational time. In this paper, a deep-learning-based stomach disease classification method employing deep feature extraction, fusion, and optimization using WCE images is proposed. The proposed method comprises several phases: data augmentation performed to increase the dataset images, deep transfer learning adopted for deep features extraction, feature fusion performed on deep extracted features, fused feature matrix optimized with a modified dragonfly optimization method, and final classification of the stomach disease was performed. The features extraction phase employed two pre-trained deep CNN models (Inception v3 and DenseNet-201) performing activation on feature derivation layers. Later, the parallel concatenation was performed on deep-derived features and optimized using the meta-heuristic method named the dragonfly algorithm. The optimized feature matrix was classified by employing machine-learning algorithms and achieved an accuracy of 99.8% on the combined stomach disease dataset. A comparison has been conducted with state-of-the-art techniques and shows improved accuracy.


Assuntos
Algoritmos , Gastropatias , Humanos , Aprendizado de Máquina , Gastropatias/diagnóstico
4.
J Vasc Surg Cases Innov Tech ; 6(2): 189-194, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32322774

RESUMO

We present a case of failed popliteal artery aneurysm repair using a Viabahn stent graft (W. L. Gore & Associates, Flagstaff, Ariz) due to laminated thrombus formation. A 75-year-old man presented with a symptomatic popliteal artery aneurysm. He was treated with a Viabahn stent graft. On follow-up, the patient complained of lower extremity claudication, and duplex ultrasound examination showed a focal intrastent stenosis. A computed tomography scan showed a significant stenosis within the stent graft, at the level of the knee joint creases. The patient underwent superficial femoral artery to distal popliteal surgery. This case report aims to expand on the mechanism of stent graft failure in popliteal aneurysms.

5.
Vascular ; 25(2): 178-183, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27370682

RESUMO

Objectives Pseudoaneurysms are a well-recognized complication of percutaneous angiographic procedures. Ultrasound-guided thrombin injection is currently the preferred treatment modality. This study was undertaken to evaluate our experience with the management of post-procedure pseudoaneurysms. Methods A retrospective study was undertaken of all patients who developed a post-procedure pseudoaneurysm between March 2004 and January 2013. Data were obtained from our prospectively maintained non-invasive vascular laboratory data base. Results Overall, 167 patients (80 men) with post-procedure pseudoaneurysms were identified. The mean age was 66 years. Post-procedure pseudoaneurysms developed following diagnostic coronary angiography (38%), coronary angioplasty (37%), peripheral vascular interventions (14.7%), or other access procedures (7.6%). Mean post-procedure pseudoaneurysm diameter was 2.8 ± 1.8 cm. One hundred forty-two post-procedure pseudoaneurysms were injected with thrombin under ultrasound guidance. Primary success rate was 93.5%. There were 12 (8.5%) procedural failures of which seven (58%) responded to reinjection, three (25%) required operative management, one was treated with ultrasound-guided compression, and one (8.3%) was simply observed. On multivariate analysis, failures were associated with increased aneurysm diameter ( p = 0.006; odds ratio 2.23, 95% CI 1.25 to 3.96), end-stage renal disease ( p = 0.013; odds ratio 1.15, 95% CI 1.09 to 1.78) and superficial femoral artery aneurysm origin ( p = 0.031; odds ratio 0.20, 95% CI 0.04 to 0.86). There were two episodes of thrombus formation in the femoral artery; one resolved with anticoagulation alone, and the other required thrombectomy. Conclusions Percutaneous ultrasound-guided thrombin injection is an effective and safe method for managing post-procedure pseudoaneurysms. Failure rates are low and associated with large aneurysm size, superficial femoral artery origin and end-stage renal disease.


Assuntos
Falso Aneurisma/etiologia , Cateterismo Cardíaco/efeitos adversos , Cateterismo Periférico/efeitos adversos , Angiografia Coronária/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Idoso , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/tratamento farmacológico , Distribuição de Qui-Quadrado , Bases de Dados Factuais , Feminino , Humanos , Injeções , Modelos Logísticos , Masculino , Michigan , Análise Multivariada , Razão de Chances , Retratamento , Estudos Retrospectivos , Fatores de Risco , Trombina/administração & dosagem , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção
6.
J Neurotrauma ; 33(1): 49-57, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25794137

RESUMO

No routine tests currently exist to objectively diagnose mild traumatic brain injury (mTBI)/concussion. Previously reported biomarkers for mTBI represented proteins released from damaged neurons or glia. However, low levels of these proteins, and/or the complexity of assays used for their detection, limits implementation of these biomarkers in routine practice. Here, we sought to identify proteins whose synthesis is altered post-mTBI and whose blood levels could be measured using standard immunoassays. Adult patients sustaining a concussion within the past 24 h were enrolled. Controls were uninjured subjects and patients with orthopedic injury (OI). Four candidate biomarkers were identified: copeptin; galectin 3 (LGALS3); matrix metalloproteinase 9 (MMP9); and occludin (OCLN). A 3.4-fold decrease (p<0.0001) in plasma concentration of copeptin was found in mTBI patients within 8 h after accident, compared to uninjured controls. Plasma levels of LGALS3, MMP9, and OCLN increased 3.6- to 4.5-fold (p<0.0001) within the same time frame postinjury. Levels of at least two biomarkers were altered beyond their respective cut-off values in 90% of mTBI patients, whereas in none of uninjured controls were levels of two biomarkers simultaneously changed. A positive correlation (r=0.681; p<0.001) between plasma levels of LGALS3 and OCLN was also found in mTBI patients, whereas in OI patients or uninjured subjects, these variables did not correlate. This panel of biomarkers discerns, with high accuracy, patients with isolated concussion from uninjured individuals within the first 8 h after accident. These biomarkers can also aid in diagnosing concussion in the presence of OI.


Assuntos
Biomarcadores/sangue , Concussão Encefálica/sangue , Galectina 3/sangue , Glicopeptídeos/sangue , Metaloproteinase 9 da Matriz/sangue , Ocludina/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Ann Thorac Surg ; 99(6): 2202-3, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26046877

RESUMO

Squamous cell carcinoma of the esophagus may be seen in patients with history of head and neck malignancies. Anatomic factors may limit management options. We present a case of second primary early cervical esophageal squamous cell cancer managed by local resection with reconstruction using a radial forearm flap.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos , Biópsia , Carcinoma de Células Escamosas/diagnóstico , Endossonografia , Neoplasias Esofágicas/diagnóstico , Carcinoma de Células Escamosas do Esôfago , Esofagoscopia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Prognóstico , Fatores de Tempo
8.
J Vasc Surg ; 57(5): 1196-203, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23384491

RESUMO

OBJECTIVE: Reports in the literature of low-energy (LE) knee dislocation (KD) in obese patients have been increasing. This study was undertaken to define the risk factors for KD by LE mechanisms and the outcomes of these patients compared with those with high-energy (HE) trauma. METHODS: All patients with a complete KD presenting to the emergency department of a large urban level I trauma center were reviewed. Patient information collected included age, sex, weight, height, body mass index (BMI), injury mechanism, neurovascular and orthopedic injuries, and operations performed to treat vascular injuries. Risk factors for KD and concomitant injuries were compared between HE traumatic dislocations and LE dislocations in obese patients (BMI >30 kg/m(2)), including stratification for increasing levels of obesity. RESULTS: Between January 1995 and April 2012, 53 patients with KD were identified. The mechanism of injury was HE in 28 (53%) and LE in 25 (47%). Of the LE KDs, 18 (72%) were related to obesity (BMI >30 kg/m(2)). Obese patients with LE trauma were more likely to have associated nerve injuries (50% vs 6%; P < .001), vascular injuries requiring intervention (33% vs 9%; P = .048), and vascular surgical repairs (28% vs 6%; P = .038) than patients with HE traumatic dislocations. These rates were highest in the patients with a BMI >40 kg/m(2). Although all LE KDs in the obese involved an isolated extremity, the hospital lengths of stay were comparable to those with HE KDs who frequently had multisystem trauma (8.7 vs 11.4 days). During a 17-year period, LE KDs in the obese represented an increasing proportion, from 17% in 1995 to 2000 up to 53% in 2007 to 2012, and the eventual majority of all KDs at our institution (P = .024). CONCLUSIONS: LE KDs in obese patients are becoming increasingly prevalent. These patients are more likely to have nerve and vascular injuries and are more likely to undergo vascular repair than patients with HE trauma. The epidemic of obesity in the United States presents unique challenges in the identification and treatment of patients with LE KD and their associated injuries.


Assuntos
Acidentes por Quedas , Acidentes de Trânsito , Luxação do Joelho/epidemiologia , Traumatismo Múltiplo , Obesidade Mórbida/epidemiologia , Lesões do Sistema Vascular/epidemiologia , Adulto , Índice de Massa Corporal , Distribuição de Qui-Quadrado , Criança , Serviço Hospitalar de Emergência , Feminino , Humanos , Luxação do Joelho/diagnóstico , Luxação do Joelho/terapia , Masculino , Michigan/epidemiologia , Pessoa de Meia-Idade , Obesidade Mórbida/diagnóstico , Prevalência , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Centros de Traumatologia , Traumatismos do Sistema Nervoso/epidemiologia , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares , Lesões do Sistema Vascular/diagnóstico , Lesões do Sistema Vascular/terapia
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