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981.
To identify neuroimaging biomarkers of alcohol dependence (AD) from structural magnetic resonance imaging, it may be useful to develop classification models that are explicitly generalizable to unseen sites and populations. This problem was explored in a mega-analysis of previously published datasets from 2,034 AD and comparison participants spanning 27 sites curated by the ENIGMA Addiction Working Group. Data were grouped into a training set used for internal validation including 1,652 participants (692 AD, 24 sites), and a test set used for external validation with 382 participants (146 AD, 3 sites). An exploratory data analysis was first conducted, followed by an evolutionary search based feature selection to site generalizable and high performing subsets of brain measurements. Exploratory data analysis revealed that inclusion of case- and control-only sites led to the inadvertent learning of site-effects. Cross validation methods that do not properly account for site can drastically overestimate results. Evolutionary-based feature selection leveraging leave-one-site-out cross-validation, to combat unintentional learning, identified cortical thickness in the left superior frontal gyrus and right lateral orbitofrontal cortex, cortical surface area in the right transverse temporal gyrus, and left putamen volume as final features. Ridge regression restricted to these features yielded a test-set area under the receiver operating characteristic curve of 0.768. These findings evaluate strategies for handling multi-site data with varied underlying class distributions and identify potential biomarkers for individuals with current AD.  相似文献   
982.
983.

Introduction

Focused parathyroidectomy in primary hyperparathyroidism (1°HPT) is possible with accurate preoperative localization and intraoperative PTH monitoring (IOPTH). The added benefit of multimodal imaging techniques for operative success is unknown.

Method

Patients with 1°HPT, who underwent parathyroidectomy in 2012–2014 at a single institution, were retrospectively reviewed. Only the patients who underwent the standardized multimodal imaging workup consisting of 123I/99Tc-sestamibi subtraction scintigraphy, SPECT, and SPECT/CT were assessed.

Results

Of 360 patients who were identified, a curative operation was performed in 96 %, using pre-operative imaging and IOPTH. Imaging analysis showed that 123I/99Tc-sestamibi had a sensitivity of 86 % (95 % CI 82–90 %), positive predictive value (PPV) 93 %, and accuracy 81 %, based on correct lateralization. SPECT had a sensitivity of 77 % (95 % CI 72–82 %), PPV 92 % and accuracy 72 %. SPECT/CT had a sensitivity of 75 % (95 % CI 70–80 %), PPV of 94 %, and accuracy 71 %. There were 3 of 45 (7 %) patients with negative sestamibi imaging that had an accurate SPECT and SPECT/CT. Of 312 patients (87 %) with positive uptake on sestamibi (93 % true positive, 7 % false positive), concordant findings were present in 86 % SPECT and 84 % SPECT/CT. In cases where imaging modalities were discordant, but at least one method was true-positive, 123I/99Tc-sestamibi was significantly better than both SPECT and SPECT/CT (p < 0.001). The inclusion of SPECT and SPECT/CT in 1°HPT imaging protocol increases patient cost up to 2.4-fold.

Conclusion

123I/99Tc-sestamibi subtraction imaging is highly sensitive for preoperative localization in 1°HPT. SPECT and SPECT/CT are commonly concordant with 123I/99Tc-sestamibi and rarely increase the sensitivity. Routine inclusion of multimodality imaging technique adds minimal clinical benefit but increases cost to patient in high-volume setting.
  相似文献   
984.
985.
986.
The purposes of this study were to analyze the effects of an ERS on time to transplantation and to describe our center's experience with OLT for HB. Patients who received OLT for HB between 2000 and 2013 were included. Patient and allograft characteristics, chemotherapy regimens, and prior surgical therapies were examined. The interval between diagnosis and OLT prior to and following the institution of an ERS for transplant was compared. Survival and tumor recurrence were analyzed. Nineteen patients received OLT for HB (mean age 33 months). All children received grafts from deceased donors. Two patients underwent prior resections. Tumor recurred in four patients (21.1%). Both patients who received salvage transplants experienced post‐OLT recurrence. Three of the four recurrences occurred in spite of adjuvant chemotherapy. There were three deaths: two from metastatic disease. One‐ and five‐yr survivals were 86.1% and 73.8%. After the institution of the ERS, the mean interval between tissue diagnosis and OLT was significantly reduced. Our series of 19 patients demonstrates a 21% recurrence of HB following OLT despite chemotherapy. Five‐yr survival reached 73.8%. A system of early referral can effectively reduce times between diagnosis and transplant.  相似文献   
987.
Resection of biopsy‐proven involved axillary lymph nodes (iALNs) is important to reduce the false‐negative rates of sentinel lymph node (SLN) biopsy after neo‐adjuvant chemotherapy (NAC) in patients with initially node‐positive breast cancer. Preoperative wire localization for iALNs marked with clips placed during biopsy is a technique that may help the removal of iALNs after NAC. However, ultrasound (US)‐guided localization is often difficult because the clips cannot always be reliably visible on US. Computed tomography (CT)‐guided wire localization can be used; however, to date there have been no reports on CT‐guided wire localization for iALNs. The aim of this study was to describe a series of patients who received CT‐guided wire localization for iALN removal after NAC and to evaluate the feasibility of this technique. We retrospectively analyzed five women with initially node‐positive breast cancer (age, 41–52 years) who were scheduled for SLN biopsy after NAC and received preoperative CT‐guided wire localization for iALNs. CT visualized all the clips that were not identified on post‐NAC US. The wire tip was deployed beyond or at the target, with the shortest distance between the wire and the index clip ranging from 0 to 2.5 mm. The total procedure time was 21–38 minutes with good patient tolerance and no complications. In four of five cases, CT wire localization aided in identification and resection of iALNs that were not identified with lymphatic mapping. Residual nodal disease was confirmed in two cases: both had residual disease in wire‐localized lymph nodes in addition to SLNs. Although further studies with more cases are required, our results suggest that CT‐guided wire localization for iALNs is a feasible technique that facilitates identification and removal of the iALNs as part of SLN biopsy after NAC in situations where US localization is unsuccessful.  相似文献   
988.
Achalasia is a motility disorder encountered by surgeons during the investigation and treatment of dysphagia. Recent advances in manometry technology, a widely accepted new classification system and a new treatment rapidly gaining international acceptance, have changed the working knowledge required to successfully manage patients with achalasia. We review the Chicago classification subtypes of achalasia with type II achalasia being a predictor of success and type III achalasia a predictor of treatment failure. We review per‐oral endoscopic myotomy as an emerging treatment option and its potential for improving the treatment of type III achalasia.  相似文献   
989.
990.

Introduction

Acute kidney injury (AKI) is a common but preventable cause of morbidity in elective arthroplasty patients. This study aimed to review the incidence and management of AKI in patients undergoing elective lower limb arthroplasty and compare results to those after the introduction of educational measures to improve prevention, recognition and management of AKI.

Methods

A retrospective case note review of all patients undergoing elective hip or knee arthroplasty between August and October 2013 was performed. Results were compared to patients treated from February to April 2014, after the introduction of a renal protection protocol, checklist poster and educational sessions. Results were statistically compared using Fisher’s exact test.

Results

Two hundred and eleven patients were included in the study: 104 in the initial cohort and 107 in the second cohort. Twenty patients (19.2 %) developed AKI in the initial cohort and 12 patients (11.2 %) in the second (p = 0.13). Recognition, documentation and management of AKI were significantly better following educational sessions and dissemination of posters throughout clinical areas, with 75 % of patients in the second cohort having their AKI documented and treated versus 30 % in the initial cohort.

Discussion/conclusions

This quality improvement project has demonstrated the significant impact that simple educational measures can have on improving AKI prevention, recognition and management in patients undergoing elective arthroplasty surgery. The introduction of a logical treatment checklist has been well received by both medical and nursing staff and ensures prompt and efficient management of AKI in a non-specialist area.
  相似文献   
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