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101.

Introduction

The purpose of this study was to develop a convolutional neural network (CNN) to determine the extent of over-scanning in the Z-direction associated with lung computed tomography (CT) examinations.

Materials and methods

The CT examinations of 250 patients were used to train the machine learning software and 100 were used to validate the results. Each lung CT examination was divided into cervical, lung, and abdominal areas by the CNN and 2 independent radiologists, and the length of each area was measured. Every part above or below the lung marks was labeled as over-scanning. The accuracy of the CNN was calculated after the training phase and agreement between CNN and radiologists was assessed using kappa statistics during the validation phase. After validation the software was used to estimate the length of each of the three areas and the total over-scanning in further 1000 patients.

Results

An accuracy of 0.99 was found for the testing dataset and a very good agreement (kappa = 0.98) between the CNN and the radiologists’ evaluation was found for the validation dataset. Over-scanning was 22.8% with the CNN and 22.2% with the radiologists. The degree of over-scanning was 22.6% in 1000 lung CT examinations.

Conclusion

Our study shows a substantial over estimation of the length of the area to be scanned during lung CT and thus an unnecessary patient's over-exposure to ionizing radiation. This over-scanning can be assessed easily, reliably and quickly using CNN.  相似文献   
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The conversion of hematopoietic to fatty marrow is known to correlate with physiologic decreases in intramedullary blood flow. To determine whether the chronology of conversion is altered in patients with hip ischemia, T1-weighted magnetic resonance (MR) images of the hips in 50 healthy people and 27 with documented avascular necrosis (AVN) were reviewed. The distribution of fatty (high-signal) versus hematopoietic (low-signal) marrow was noted with respect to age. All patients had fatty marrow in the femoral capital epiphysis and greater trochanter. Hematopoietic intertrochanteric marrow was seen in 95% (80 of 84) of femurs in control subjects less than 50 years old, but in only 12.5% (two of 16) of those in control subjects older than 50 years (P less than .005). Only 33% (19 of 57) of patients less than 50 years with AVN had predominantly hematopoietic intertrochanteric marrow (P less than .005). The early conversion to fatty marrow in most patients with AVN as depicted by MR imaging may be an effect of decreased vascularity of the proximal femur and may allow the identification of patients at increased risk for AVN.  相似文献   
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BACKGROUND: Over the last few years, high-dose chemotherapy has been extensivelyinvestigated in relapsing/refractory non-Hodgkin's lymphoma(NHL). However, this approach is reserved to a limited subsetof cases and new conventional-dose second-line chemotherapiesneed to be investigated. PATIENTS AND METHODS: Thirty consecutive out-patients with refractory or recurrentNHL were given polychemotherapy in a regimen consisting of ifosfamide,mitoxantrone and etoposide on day 1 and vindesine, cisplatinumand cytosine arabinoside on day 15: courses were repeated every29 days. Five patients had refractory disease following first-linechemotherapy and 25 were relapsing. RESULTS: The median number of administered cycles was 4 (range 2–8).We observed 16 complete (53%; 95% confidence interval, 34%–72%)and 3 partial remissions, for an overall remission rate of 63%(95% confidence interval, 44%–80%). Responses were seenonly among patients who achieved at least a partial responseduring first-line therapy. The median duration of complete remissionwas 15 months (range 5–47+), whereas median survival ofthe treated patients was 26 months (range 2–50+). Fivepatients were long-term responders after 34+, 35+, 46+, 46+and 47+ months. No-life threatening toxicity was observed. Themain side effects were myelosuppression, nausea/vomiting andalopecia. CONCLUSIONS: The proposed regimen is feasible and effective in terms of completeremission rate and disease-free survival, suggesting that thistreatment may be potentially curative in a subgroup of relapsedpatients with limited tumor burden and normal LDH values. Amore aggressive approach is needed in refractory patients. non-Hodgkin's lymphoma, salvage chemotherapy  相似文献   
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Background: Vinorelbine, is an active drug in the treatment of metastatic breast cancer and has a favorable toxicity profile. Its combination with other effective and well-tolerated cytotoxics may thus be beneficial. We investigated the therapeutic effect of a combination of vinorelbine plus 5-fluorouracil and folinic acid as first-line treatment in patients with metastatic breast cancer.Patients and methods: Forty-five patients with advanced or metastatic breast cancer were enrolled in this phase I–II study and treated with 5-fluorouracil (350 mg/m2 i.v. on day 1 to 3), folinic acid (100 mg/m2 i.v. on day 1 to 3) and vinorelbine given on days 1 and 3 at the dose of 25 mg/m2 (dose level 1), or 30 mg/m2 (dose level 2). Therapy was given on an outpatient basis every three weeks.Results: Phase I: Dose limiting toxicity (DLT) occurred at the second dose level of vinorelbine (30 mg/m2), with two out of three patients developing severe constipation (ileus-like syndrome grade 4), and fever (grade 2). Consequently, the dose evaluated in the phase II study was 25 mg/m2. Phase II: Objective responses were observed in 24 of 39 evaluable patients (95% confidence interval (95% CI), 47% to 77%). There were seven complete responses (18%), 17 partial responses (44%), and for nine patients (23%) disease was stable. Only six patients (15%) experienced disease progression. The median response duration was 10 months (range 6 to 24+) and the median time to progression was eight months (range 2 to 24+). Granulocytopenia was the most frequently observed side effect, with a grade 4 nadir being observed in 30 patients (77%), with four hospital admissions due to febrile neutropenia. Nausea, vomiting, and anorexia were mild to moderate and reported by less than half of the patients. Alopecia was moderate and occurred in about one-third of the patients. The other side effects were mild and easily manageable.Conclusions: This effective combination chemotherapy of vinorelbine, 5-fluorouracil and folinic acid is comparable to other first-line regimens in terms of efficacy, and is subjectively well tolerated, thus deserving a test in randomized trials in the advanced and adjuvant settings.  相似文献   
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