12 research outputs found

    Phase aberration correction method for ultrasound imaging

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    A computationally efficient method for phase aberration correction in ultrasound imaging is presented. The method is based on time delay estimation via minimization of the sum of absolute differences between radio frequency samples of adjacent array elements. Effects of averaging estimated aberration patterns over scan angles, and truncation to a single bit wordlength are examined. Phase distortions due to near-field inhomogeneities are simulated using silicone rubber aberrators. Performance of the method is tested using experimental data. Simulation studies addressing different factors affecting efficiency of the method, such as the number of iterations, window length, and the number of scan angles used for averaging, are presented. Images of a standard resolution phantom are reconstructed and used for qualitative testing

    Çocuklarda influenza A ve B enfeksiyonlarının klinik ve laboratuvar özelliklerinin karşılaştırılması

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    Aim: In this study, we aimed to compare the clinical and laboratory findings of Influenza A and Influenza B infections in children. Methods: The study included 1826 pediatric patients (aged <16 years) who were di¬agnosed with Influenza A (n=1400) and B (n=426) infections between 1 October 2019 and 30 April 2020. The patients were also divided into age groups: the age groups of 0–2 years, 3–9 years, and 10–16 years. The characteristic clinical and laboratory findings were compared. Results: Influenza A infection was significantly more common in patients aged <2 years and was significantly less common in patients aged 3–9 years. Body temperature was significantly higher in all age groups with Influenza A infection than in children with Influenza B infection. While leukocy¬tosis and lymphopenia were significantly more common in the Influenza A group, leukopenia and neutropenia were significantly more common in the Influenza B group. While acute otitis media was more common in Influenza A infection, myositis was more common in Influenza B infection. No significant difference was found between the Influenza A and B groups in terms of hospitalization rates. Of all patients, 98.3% were treated with oseltamivir. Conclusion: Our findings indicate that Influenza A and B infections are, in general, very similar in terms of symptoms. However, Influenza A infection is more common in very young children. It progresses with higher fever and is more frequently associated with pharyngeal hy¬peremia and acute otitis media, while leukopenia, neutropenia, conjunctivitis, nasal discharge, and myositis were found to be more common in Influenza B infection.Amaç: Bu çalışmada, çocuklarda İnfluenza A ve İnfluenza B enfeksiyonlarının klinik ve laboratuvar bulgularını karşılaştırmak amaçlanmıştır. Yöntem: Çalışma 1 Ekim 2019 ile 30 Nisan 2020 tarihleri arasında İnfluenza A (n=1400) ve B (n=426) enfeksiyonu tanısı almış 16 yaş altı 1826 çocuk hasta içerdi. Hastalar aynı zamanda yaş gruplarına ayrıldı: 0–2 (yıl) yaş grubu, 3–9 yaş grubu, ve 10–16 yaş grubu. Karakteristik klinik bulgu¬lar ve laboratuvar bulguları karşılaştırıldı. Bulgular: İnfluenza A enfeksiyonu <2 yaşındaki hastalarda anlamlı biçimde daha yaygın, 3–9 ya¬şındaki hastalarda anlamlı biçimde daha enderdi. Vücut sıcaklığı İnfluenza A enfeksiyonlu tüm yaş gruplarında İnfluenza B enfeksiyonlu çocuklara göre anlamlı biçimde daha yüksekti. İnfluenza A grubunda lökositoz ve lenfopeni anlamlı biçimde daha yaygınken, İnfluenza B grubunda lökopeni ve nötropeni anlamlı biçimde daha yaygındı. Akut orta kulak iltihabı İnfluenza A enfeksiyonunda daha yaygınken, miyozit İnfluenza B enfeksiyonunda daha yaygındı. Hastaneye yatış oranı açısından ise İnfluenza A ve B grupları arasında anlamlı fark bulunmadı. Tüm hastaların %98,3’ü oseltamivir ile tedavi edildi. Sonuç: Bulgularımız İnfluenza A ve B enfeksiyonlarının semptomlar açısından genel olarak çok benzer olduğuna işaret etmektedir. Bununla birlikte, İnfluenza A enfeksiyonu çok küçük çocuklarda daha yaygındır. Daha yüksek ateşle ilerler ve farengeal hiperemi ve akut orta kulak ilti¬habı daha sık görülür. Lökopeni, nötropeni, konjonktivit, burun akıntısı ve miyozitin ise İnfluenza B enfeksiyonunda daha yaygın olduğu tespit edilmiştir

    Bipolar or Unipolar Hemiarthroplasty after Femoral Neck Fracture in the Geriatric Population

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    Background: The choice of prosthesis in hemiarthroplasty is controversial for geriatric patients after femoral neck fracture. We hypothesised that selection criteria for unipolar or bipolar prostheses could be constructed based on factors affecting mortality. Aims: The aims of this retrospective study were: (1) to determine the factors affecting mortality of femoral neck fracture patients ≥65 years of age; (2) to compare patient mortality rates, radiological findings, and functional outcomes according to prosthesis type (unipolar or bipolar); and (3) to evaluate the persistence of inner bearing mobility of bipolar prostheses. Study Design: Retrospective comparative study. Methods: In total, 144 patients operated for hemiarthroplasty and aged ≥65 were included. We classified the patients into either unipolar or bipolar prosthesis groups. To reveal factors that affected mortality, age, sex, delay in surgery, and American Society of Anesthesiologists score were obtained from folders. Barthel Daily Living, Harris hip, and acetabular erosion scores were calculated and bipolar head movement was analysed for live patients. Results: One-year mortality was 31.94%. Age ≥75 (p=0.029), male sex (p=0.048), and delay in surgery ≥6 (p=0.004) were the patient characteristics that were related to increased mortality. There were no significant differences in sex, age, American Society of Anesthesiologists score, delay in surgery, mortality, or Barthel, Harris, acetabulum scores between the two groups. Twenty patients from each group were admitted for last follow-up. Bipolar head movement was preserved for 33.3% of patients. They were inactive patients with low Barthel and Harris scores. Conclusion: Although bipolar head movement was preserved in inactive patients, we suppose that this conferred no advantage to these patients, who could hardly walk. In this study, male patients, those aged ≥75 years, and those operated at ≥6 days had an increased risk of mortality. Also, although not significant in multivariate analysis, high American Society of Anesthesiologists score (≥3) was related to increased mortality. Considering that one of three patients died during the first postoperative year, we think that these patients should be operated as soon as possible, and expensive bipolar prostheses must be used selectively in regard to patient characteristics

    Bipolar or Unipolar Hemiarthroplasty after Femoral Neck Fracture in the Geriatric Population

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    Background: The choice of prosthesis in hemiarthroplasty is controversial for geriatric patients after femoral neck fracture. We hypothesised that selection criteria for unipolar or bipolar prostheses could be constructed based on factors affecting mortality. Aims: The aims of this retrospective study were: (1) to determine the factors affecting mortality of femoral neck fracture patients ≥65 years of age; (2) to compare patient mortality rates, radiological findings, and functional outcomes according to prosthesis type (unipolar or bipolar); and (3) to evaluate the persistence of inner bearing mobility of bipolar prostheses. Study Design: Retrospective comparative study. Methods: In total, 144 patients operated for hemiarthroplasty and aged ≥65 were included. We classified the patients into either unipolar or bipolar prosthesis groups. To reveal factors that affected mortality, age, sex, delay in surgery, and American Society of Anesthesiologists score were obtained from folders. Barthel Daily Living, Harris hip, and acetabular erosion scores were calculated and bipolar head movement was analysed for live patients. Results: One-year mortality was 31.94%. Age ≥75 (p=0.029), male sex (p=0.048), and delay in surgery ≥6 (p=0.004) were the patient characteristics that were related to increased mortality. There were no significant differences in sex, age, American Society of Anesthesiologists score, delay in surgery, mortality, or Barthel, Harris, acetabulum scores between the two groups. Twenty patients from each group were admitted for last follow-up. Bipolar head movement was preserved for 33.3% of patients. They were inactive patients with low Barthel and Harris scores. Conclusion: Although bipolar head movement was preserved in inactive patients, we suppose that this conferred no advantage to these patients, who could hardly walk. In this study, male patients, those aged ≥75 years, and those operated at ≥6 days had an increased risk of mortality. Also, although not significant in multivariate analysis, high American Society of Anesthesiologists score (≥3) was related to increased mortality. Considering that one of three patients died during the first postoperative year, we think that these patients should be operated as soon as possible, and expensive bipolar prostheses must be used selectively in regard to patient characteristics

    Rotational malalignment after closed intramedullary nailing of femoral shaft fractures and its influence on daily life

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    Background: Any intraoperative rotational malalignment during intramedullary nailing (IMN) of femoral shaft fractures will become permanent. We hypothesized that rotational malalignment of the femur and its compensatory biomechanics may induce problems in the hip, knee, patellofemoral and ankle joints. We purposed to clarify the influence of a femoral rotational malalignment of ?10° on daily activities. Methods: Twenty-four femoral shaft fracture patients treated with closed antegrade IMN were included. At last follow-up, to reveal any rotational malalignment, computerized tomography (CT) scans of both femurs (injured and uninjured sides) were examined. The patient groups with or without CT-detected true rotational malalignment ?10° were compared with respect to the activity scores. Results: Ten of the 24 patients (41.7 %) had a CT-detected true rotational malalignment of ?10° compared with the unaffected side. The AOFAS scores were 100.00 for all of the patients. LKS, WOMAC knee, and WOMAC hip scores were significantly decreased in the patients with rotational malalignment compared to those without. Patients without rotational malalignment tolerated climbing stairs significantly better than those with rotational malalignment. Patients who could not tolerate climbing stairs were consistently complaining of anterior knee pain. Conclusions: A femoral rotational malalignment of ?10° is symptomatic for the patients, and the hip, knee, and patellofemoral joints were affected. Because of the possibly altered joint loadings and biomechanics, these could render patients prone to degenerative joint disease. In addition, due to the high rates of rotational malalignment after femoral shaft fracture and consequent malpractice claims, it is important for surgeons to be more aware of rotational alignment during surgery
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