Precision of orthodontic cephalometric measurements on ultra low dose-low dose CBCT reconstructed cephalograms

ObjectivesTo analyze differences in variation of orthodontic diagnostic measurements on lateral cephalograms reconstructed from ultra low dose-low dose (ULD-LD) cone beam computed tomography (CBCT) scans (RLC) as compared to variation of measurements on standard lateral cephalograms (SLC), and to determine if it is justifiable to replace a traditional orthodontic image set for an ULD-LD CBCT with a reconstructed lateral cephalogram.Material and methodsULD-LD CBCT images and SLCs were made of forty-three dry human skulls. From the ULD-LD CBCT dataset, a lateral cephalogram was reconstructed (RLC). Cephalometric landmarks (13 skeletal and 7 dental) were identified on both SLC and RLC twice in two sessions by two calibrated observers. Thirteen cephalometric variables were calculated. Variations of measurements, expressed as standard deviations of the 4 measurements on SLC and RLC, were analyzed using a paired sample t-test. Differences in the number of observations deviating &gt;= 2.0 mm or degrees from the grand mean between SLC and RLC were analyzed using a McNemar test.ResultsMean SDs for 7 out of 13 variables were significantly smaller for SLCs than those for RLCs, but differences were small. For 9 out of 13 variables, there was no significant difference between SLC and RLC for the number of measurements outside the range of 2 mm or degrees.ConclusionsBased on the lower radiation dose and the small differences in variation in cephalometric measurements on reconstructed LC compared to standard dose LC, ULD-LD CBCT with reconstructed LC should be considered for orthodontic diagnostic purposes.</p

Precision of orthodontic cephalometric measurements on ultra low dose-low dose CBCT reconstructed cephalograms.

OBJECTIVES To analyze differences in variation of orthodontic diagnostic measurements on lateral cephalograms reconstructed from ultra low dose-low dose (ULD-LD) cone beam computed tomography (CBCT) scans (RLC) as compared to variation of measurements on standard lateral cephalograms (SLC), and to determine if it is justifiable to replace a traditional orthodontic image set for an ULD-LD CBCT with a reconstructed lateral cephalogram. MATERIAL AND METHODS ULD-LD CBCT images and SLCs were made of forty-three dry human skulls. From the ULD-LD CBCT dataset, a lateral cephalogram was reconstructed (RLC). Cephalometric landmarks (13 skeletal and 7 dental) were identified on both SLC and RLC twice in two sessions by two calibrated observers. Thirteen cephalometric variables were calculated. Variations of measurements, expressed as standard deviations of the 4 measurements on SLC and RLC, were analyzed using a paired sample t-test. Differences in the number of observations deviating ≥ 2.0 mm or degrees from the grand mean between SLC and RLC were analyzed using a McNemar test. RESULTS Mean SDs for 7 out of 13 variables were significantly smaller for SLCs than those for RLCs, but differences were small. For 9 out of 13 variables, there was no significant difference between SLC and RLC for the number of measurements outside the range of 2 mm or degrees. CONCLUSIONS Based on the lower radiation dose and the small differences in variation in cephalometric measurements on reconstructed LC compared to standard dose LC, ULD-LD CBCT with reconstructed LC should be considered for orthodontic diagnostic purposes. CLINICAL RELEVANCE ULD-LD CBCT with reconstructed LC should be considered for orthodontic purposes

Even “lurkers” download: the behavior and illegal activities of members on a child sexual exploitation TOR hidden service

Criminal Justice: Legitimacy, accountability, and effectivit

Characterisation, degradation and regeneration of luminescent Ag29 clusters in solution

Luminescent Ag clusters are prepared with lipoic acid (LA) as the ligand. Using a combination of mass spectrometry, optical spectroscopy and analytical ultracentrifugation, the clusters are found to be highly monodisperse with mass 5.6 kDa. We assign the chemical composition [Ag29(LA)12](3-) to the clusters, where LA likely binds in a bidentate fashion. The Ag29 clusters show slow degradation, retaining their deep red emission for at least 18 months if stored in the dark. Purification or exposure to light results in faster degradation. No other cluster species are observed during the degradation process. Once degraded, the clusters could easily be regenerated using NaBH4, which is not usually observed for thiolate-capped Ag clusters

Quality of Life After Pelvic Radiotherapy or Vaginal Brachytherapy for Endometrial Cancer: First Results of the Randomized PORTEC-2 Trial

Purpose Studies on quality of life (QOL) among women with endometrial cancer have shown that patients who undergo pelvic radiotherapy report lower role functioning and more diarrhea and fatigue. In the Post Operative Radiation Therapy in Endometrial Cancer (PORTEC) trial, patients with endometrial carcinoma were randomly assigned to receive external-beam radiotherapy (EBRT) or vaginal brachytherapy (VBT). QOL was evaluated by using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 and subscales from the prostate cancer module, PR-25, and the ovarian cancer module, OV-28. Patients and Methods PORTEC-2 accrued 427 patients between 2002 and 2006, of whom 214 were randomly assigned to EBRT, and 213 were randomly assigned to VBT. Three-hundred forty-eight patients (81%) were evaluable for QOL. QOL outcomes were analyzed at a median follow-up of 2 years. Results At baseline after surgery, patient functioning was at the lowest level, and it increased during and after radiotherapy to reach a plateau after 12 months. Patients in the VBT group reported better social functioning (P < .002) and lower symptom scores for diarrhea, fecal leakage, the need to stay close to the toilet, and limitation in daily activities because of bowel symptoms (P < .001). At baseline, 15% of patients were sexually active; this increased significantly to 39% during the first year (P < .001). Sexual functioning and symptoms did not differ between the treatment groups. Conclusion Patients who received EBRT reported significantly higher levels of diarrhea and bowel symptoms. This resulted in a higher need to remain close to a toilet and, as a consequence, more limitation of daily activities because of bowel symptoms and decreased social functioning. Vaginal brachytherapy provides a better QOL, and should be the preferred treatment from a QOL perspective

A Fuzzy-Rule-Based Model for Handling Contextual Preference Queries

Usersarsquo; preferences have traditionally been exploited in query personalization to better serve their information needs. Most of the time, user preferences depend on context, that is, they may have different values depending on the situation of the user. In this paper, we propose a fuzzy-rule-based model for the representation of contextual preferences in a database querying framework. We discuss the augmentation of a query with preferences deduced from information regarding the current context of the user. To this end, we make use of an appropriate inference pattern, called , able to deal with data and knowledge when they are described in a fuzzy way

Vaginal brachytherapy versus pelvic external beam radiotherapy for patients with endometrial cancer of high-intermediate risk (PORTEC-2): an open-label, non-inferiority, randomised trial

Background After surgery for intermediate-risk endometrial carcinoma, the vagina is the most frequent site of recurrence. This study established whether vaginal brachytherapy (VBT) is as effective as pelvic external beam radiotherapy (EBRT) in prevention of vaginal recurrence, with fewer adverse effects and improved quality of life. Methods In this open-label, non-inferiority, randomised trial undertaken in 19 Dutch radiation oncology centres, 427 patients with stage I or IIA endometrial carcinoma with features of high-intermediate risk were randomly assigned by a computer-generated, biased coin minimisation procedure to pelvic EBRT (46 Gy in 23 fractions; n=214) or VBT (21 Gy high-dose rate in three fractions, or 30 Gy low-dose rate; n=213). All investigators were masked to the assignment of treatment group. The primary endpoint was vaginal recurrence. The predefined non-inferiority margin was an absolute difference of 6% in vaginal recurrence. Analysis was by intention to treat, with competing risk methods. The study is registered, number ISRCTN16228756. Findings At median follow-up of 45 months (range 18-78), three vaginal recurrences had been diagnosed after VBT and four after EBRT. Estimated 5-year rates of vaginal recurrence were 1.8% (95% CI 0.6-5.9) for VBT and 1.6% (0.5-4-9) for EBRT (hazard ratio [HR] 0.78, 95% CI 0-17-3.49; p=0.74). 5-year rates of locoregional relapse (vaginal or pelvic recurrence, or both) were 5.1% (2.8-9.6) for VBT and 2.1% (0.8-5.8) for EBRT (HR 2.08,0.71-6.09; p=0.17). 1.5% (0.5-4.5) versus 0.5% (0.1-3.4) of patients presented with isolated pelvic recurrence (HR 3.10, 0.32-29.9; p=0.30), and rates of distant metastases were similar (8.3% [5.1-13.4] vs 5.7% [3.3-9.9]; HR 1.32, 0.63-2.74; p=0.46). We recorded no differences in overall (84-8% [95% CI 79.3-90.3] vs 79.6% [71.2-88.0]; HR 1.17, 0.69-1.98; p=0.57) or disease-free survival (82.7% [76.9-88.6] vs 78.1% [69.7-86.5]; HR 1.09, 0.66-1.78; p=0.74). Rates of acute grade 1-2 gastrointestinal toxicity were significantly lower in the VBT group than in the EBRT group at completion of radiotherapy (12.6% [27/215] vs 53.8% [112/208]). Interpretation VBT is effective in ensuring vaginal control, with fewer gastrointestinal toxic effects than with EBRT. VBT should be the adjuvant treatment of choice for patients with endometrial carcinoma of high-intermediate risk.Immunology and molecular genetics of gynecological cancersBiological, physical and clinical aspects of cancer treatment with ionising radiationClinical OncologyTI9 - Endometriumpathologi