53 research outputs found

    Sustaining accelerated rates of improvement

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering; and, Thesis (M.S.)--Sloan School of Management, 1997.Includes bibliographical references (p. 86).by Valerie Feliberti.M.S

    Multi-Modality Breast MRI Segmentation Using nn-UNet for Preoperative Planning of Robotic Surgery Navigation

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    Segmentation of the chest region and breast tissues is essential for surgery planning and navigation. This paper proposes the foundation for preoperative segmentation based on two cascaded architectures of deep neural networks (DNN) based on the state-of-the-art nnU-Net. Additionally, this study introduces a polyvinyl alcohol cryogel (PVA-C) breast phantom based on the segmentation of the DNN automated approach, enabling the experiments of navigation system for robotic breast surgery. Multi-modality breast MRI datasets of T2W and STIR images were acquired from 10 patients. Segmentation evaluation utilized the Dice Similarity Coefficient (DSC), segmentation accuracy, sensitivity, and specificity. First, a single class labeling was used to segment the breast region. Then it was employed as an input for three-class labeling to segment fat, fibroglandular (FGT) tissues, and tumorous lesions. The first architecture has a 0.95 DCS, while the second has a 0.95, 0.83, and 0.41 for fat, FGT, and tumor classes, respectively

    Migration of silicone gel into breast parenchyma following mammary prosthesis rupture

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    The case report of a patient with a ruptured gel mammary prosthesis complicated by migration of the gel into the breast parenchyma is presented. It is felt that the constant massage of the prostheses in an attempt to avoid fibrous contracture after closed capsulotomy is the etiology for this migration. The prosthesis and extruded gel were removed by sacrificing breast parenchyma. Repeated prosthesis massage after closed capsulotomy exposes the patient to significant potential complication if the prosthesis has been ruptured.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48160/1/266_2005_Article_BF01570670.pd

    Trials and Tribulations of Humanizing Mice for Cancer Research

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    Cancers are aggressive, evasive, and ruthless killers, claiming millions of lives every year. Cancers are heterogeneous and there is often no single, clearly defined problem as they harness and manipulate a multitude of fundamental mechanisms at the very essence of life. To investigate these mechanisms and vet potential interventive therapies, humanized mice offer a unique model as a prelude to the use of nanosecond pulse stimulation (NPS), a pulse power technology applying nanosecond duration, high electric field pulses, to ablate human tumors. Immunodeficient mouse strains, NSG and NSG-SGM3, were engrafted with human immune cells and human tumors, which would allow us to study the effects of NPS therapy on the human tumor and the human immune system, albeit not without trials and tribulations. Here we show that mice engrafted with human cord blood CD34+ hematopoietic stem cells (hCD34+ HSC) lack consistency in expansion and chimerism, or variety of immune cell types. Unfortunately, mice that developed the human immune system rejected the human tumors without treatment, while mice that rejected the immune system developed the human tumors. Therefore, we had mice with human immune systems and no tumor to treat, and mice with tumors to treat yet no immune system to study. In non-humanized mice, NPS induced complete tumor death in the patient derived mammary cancer xenograft (PDX) model, but not in the MDA-MB-231 VIM-RFP mammary cancer cell-derived xenograft (CDX) model. The absence of NPS elimination of the CDX is the only known NPS cancer failure and requires further study.https://digitalcommons.odu.edu/gradposters2021_gradschool/1000/thumbnail.jp

    The relationship between quality of life and compliance to a brace protocol in adolescents with idiopathic scoliosis: a comparative study

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    <p>Abstract</p> <p>Background</p> <p>Corrective bracing for adolescent idiopathic scoliosis (AIS) has favourable outcomes when patients are compliant. However, bracing may be a stressful and traumatic experience and compliance with a bracing protocol is likely to be dependent upon patients' physical, emotional and social wellbeing. The Brace Questionnaire (BrQ), a recently-developed, condition-specific tool to measure quality of life (QOL) has enabled clinicians to study relationships between QOL and compliance.</p> <p>Methods</p> <p>The BrQ was administered to 31 AIS patients after a minimum of 1 year of wearing a brace. Subjects were 13–16 year old South African girls with Cobb angles of 25–40 degrees. Participants were divided into two groups according to their level of compliance with the bracing protocol. Brace Questionnaire sub- and total scores were compared between the two groups using the t-test for comparison of means.</p> <p>Results</p> <p>Twenty participants were classified as compliant and 11 as non-compliant. Mean total BrQ scores (expressed as a percentage) were 83.7 for the compliant group and 64.4 for the non-compliant group (p < 0.001), and on analysis of the 8 domains that make up the BrQ, the compliant group scored significantly higher in the 6 domains that measured vitality and social, emotional and physical functioning.</p> <p>Conclusion</p> <p>Poor compliance with a brace protocol is associated with poorer QOL, with non-compliant patients lacking vitality and functioning poorly physically, emotionally and socially. Quality of life for adolescents with idiopathic scoliosis may relate more to psychosocial coping mechanisms than to physical deformity and its consequences. It is important to establish whether remedial programmes are capable of addressing personal, group and family issues, improving QOL and promoting compliance.</p

    The influence of elastic orthotic belt on sagittal profile in adolescent idiopathic thoracic scoliosis: a comparative radiographic study with Milwaukee brace

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    <p>Abstract</p> <p>Background</p> <p>The effectiveness of bracing on preventing curve progression in coronal plane for mild and moderate adolescent idiopathic scoliosis (AIS) patients has been confirmed by previous radiographic researches. However, a hypokyphotic effect on the sagittal plane has been reported by a few studies. A relatively increasing number of AIS patients were noticed to wear a new kind of elastic orthotic belt for the treatments of scoliosis without doctors' instructions. We postulate the correcting mechanism of this new appliance may cause flattening of the spine. To our knowledge, no study has investigated the effects of this new orthosis on the sagittal profile of AIS patients. The aim of this study was to evaluate and compare the effects of elastic orthotic belt and Milwaukee brace on the sagittal alignment in AIS patients.</p> <p>Methods</p> <p>Twenty-eight female AIS patients with mild or moderate thoracic curves were included in this study. Standing full-length lateral radiographs were obtained in three conditions: natural standing posture without any treatment, with elastic orthotic belt and with Milwaukee brace. Thoracic kyphosis (TK), lumber lordosis (LL) and pelvic incidence (PI) were measured and compared between the above three conditions.</p> <p>Results</p> <p>Both elastic orthotic belt and Milwaukee brace can lead to significant decrease of TK, however, the decrease of TK after wearing elastic orthotic belt is significantly larger than that after wearing Milwaukee brace. Compared with no treatment, LL was found to be significantly smaller after wearing Milwaukee brace, however, such significant decrease was not noted after wearing elastic orthotic belt. No significant changes were observed for the PI between 3 conditions.</p> <p>Conclusions</p> <p>The elastic orthotic belt could lead to more severe thoracic hypokyphosis when compared with Milwaukee brace. This belt may not be a suitable conservative method for the treatment of mild and moderate AIS patients.</p

    Isolated T Wave Inversion in Lead aVL: An ECG Survey and a Case Report

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    Background. Computerized electrocardiogram (ECG) analysis has been of tremendous help for noncardiologists, but can we rely on it? The importance of ST depression and T wave inversions in lead aVL has not been emphasized and not well recognized across all specialties. Objective. This study\u27s goal was to analyze if there is a discrepancy of interpretation by physicians from different specialties and a computer-generated ECG reading in regard to a TWI in lead aVL. Methods. In this multidisciplinary prospective study, a single ECG with isolated TWI in lead aVL that was interpreted by the computer as normal was given to all participants to interpret in writing. The readings by all physicians were compared by level of education and by specialty to one another and to the computer interpretation. Results. A total of 191 physicians participated in the study. Of the 191 physicians 48 (25.1%) identified and 143 (74.9%) did not identify the isolated TWI in lead aVL. Conclusion. Our study demonstrated that 74.9% did not recognize the abnormality. New and subtle ECG findings should be emphasized in their training so as not to miss significant findings that could cause morbidity and mortality

    Clinical improvement and radiological progression in a girl with early onset scoliosis (EOS) treated conservatively – a case report

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    BACKGROUND: Chêneau-Brace treatment of a certain standard reduces the rate of surgery, prevents progression and in a certain patient population leads to marked improvement of Cobb angle and cosmetic appearance. During the last two years a patient refusing surgery with a double major curvature of initially 60° showed a clear cosmetic improvement and a clear radiological progression at the same time. The findings of this patient have been reviewed in order to find out how cosmetic appearance and Cobb angle can develop differently. METHODS: The patient entered conservative treatment at the age of 13 years, premenarchial with Tanner II and a Cobb angle of 60° thoracic and 59° lumbar. The angle of trunk rotation (ATR; Scoliometer) was 13° thoracic and 13° lumbar. We have documented the findings of this patient (Surface topography, ATR, Cobb angles and angles of vertebral rotation (according to Raimondi) during the treatment period (27 Month) until 2 years after the onset of menarche. RESULTS: After a treatment time of 27 Month the Cobb angle increased to 74° thoracic and 65° lumbar. The angles of vertebral rotation according to Raimondi increased slightly from 26° thoracic and 28° lumbar to 30° thoracic and 28° lumbar. The ATR improved to 12° thoracic and 5° lumbar while Lateral deviation improved from 22,4 mm to 4,6 mm and average surface rotation improved from 10,6° to 6°. In the X-rays a reduction of decompensation was visible. The patient felt comfortable with the cosmetic result. CONCLUSION: Conservative treatment may improve cosmetic appearance while the curve progresses radiologically. This could be explained by assuming that (1) the Rigo Chêneau brace is able to improve cosmetic appearance by changing the shape of the thorax when the curve itself is too stiff to be corrected by a brace, that (2) reduction of decompensation leads to significant cosmetical improvements or (3) that the patient gained weight and therefore the deformation is masked. However, the weight the patient gained cannot explain the cosmetical improvement in this case. Conservative treatment with a certain standard of quality seems a viable alternative for patients with Cobb angles of > 60° when surgical treatment is refused. Specialists in scoliosis management should be aware of the fact that curve progression can occur even if the clinical measurements show an improvement

    Braces for idiopathic scoliosis in adolescents. A cochrane review

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    STUDY DESIGN. Cochrane systematic review. OBJECTIVE. To evaluate the efficacy of bracing in adolescent patients with adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA. AIS is a 3-dimensional deformity of the spine. Although AIS can progress during growth and cause a surface deformity, it is usually not symptomatic. However, in adulthood, if the final spinal curvature surpasses a certain critical threshold, the risk of health problems and curve progression is increased. Braces are traditionally recommended to stop curvature progression in some countries and criticized in others. They generally need to be worn full time, with treatment extending over years. METHODS. The following databases (up to July 2008) were searched with no language limitations: the Cochrane Central Register of Controlled Trials, MEDLINE (from January 1966), EMBASE (from January 1980), and CINHAL (from January 1982), and reference lists of the articles. An extensive handsearch of the gray literature was also conducted. Randomized controlled trials (RCTs) and prospective cohort studies were searched for comparing braces with no treatment, other treatment, surgery, and different types of braces. Two review authors independently assessed trial quality and extracted data. RESULTS. We included 2 studies. There was very low quality evidence from 1 prospective cohort study with 286 girls that a brace curbed curve progression at the end of growth (success rate, 74 95% confidence interval {CI}: 52%-84%), better than observation (success rate, 34% 95% CI: 16%-49%) and electrical stimulation (success rate, 33% 95% CI: 12%-60%). There is low-quality evidence from 1 RCT with 43 girls that a rigid brace is more successful than an elastic one (SpineCor) at curbing curve progression when measured in Cobb degrees, but there were no significant differences between the 2 groups in the subjective perception of daily difficulties associated with wearing the brace. CONCLUSION. There is very low quality evidence in favor of using braces, making generalization very difficult. Further research could change the actual results and our confidence in them; in the meantime, patients' choices should be informed by multidisciplinary discussion. Future research should focus on short- and long-term patient-centered outcomes, in addition to measures such as Cobb angles. RCTs and prospective cohort studies should follow both the Scoliosis Research Society and Society on Scoliosis Orthopedic and Rehabilitation Treatment criteria for bracing studies. © 2010, Lippincott Williams & Wilkins
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