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Reirradiation of head and neck squamous cell carcinomas: a pragmatic approach-part I: prognostic factors and indications to treatment.
Get PDFINTRODUCTION
Reirradiation (reRT) of locally recurrent/second primary tumors of the head and neck region is a potentially curative treatment for patients not candidate to salvage surgery. Aim of the present study is to summarize available literature on both prognostic factors and indications to curative reRT in this clinical setting.
MATERIALS AND METHODS
A narrative review of the literature was performed on two topics: (1) patients' selection according to prognostic factors and (2) dosimetric feasibility of reRT. Postoperative reRT and palliative intent treatments were out of the scope of this work.
RESULTS
Patient-tumor and treatment-related prognostic factors were analyzed, together with dosimetric parameters concerning target volume and organs at risk. Based on available evidence, a stepwise approach has been proposed aiming to provide a useful tool to identify suitable candidates for curative reRT in clinical practice. This was then applied to two clinical cases, proposed at the end of this work.
CONCLUSION
A second course of RT in head and neck recurrence/second primary tumors is a personalized approach that can be offered to selected patients only in centers with expertise and dedicated equipment following a multidisciplinary team discussion
NEW GENERATION OF SUPERIOR SINGLE PLATING VS LOW-PROFILE DUAL MINI-FRAGMENT PLATING IN DIAPHYSEAL CLAVICLE FRACTURES. A BIOMECHANICAL COMPARATIVE STUDY.
Get PDFBACKGROUND
Recently, a new generation of superior clavicle plates was developed featuring the variable angle locking technology for enhanced screw positioning and a less prominent and optimized plate-to-bone fit design. On the other hand, mini-fragment plates in dual plating mode have demonstrated promising clinical results. The aim of the current study was to compare the biomechanical competence of single superior plating using the new generation plate versus dual plating using low-profile mini-fragment plates.
METHODS
Sixteen paired human cadaveric clavicles were pairwise assigned to two groups for instrumentation with either a superior 2.7 mm Variable Angle Locking Compression Plate (Group 1), or with one 2.5 mm anterior combined with one 2.0 mm superior matrix mandible plate (Group 2). An unstable clavicle shaft fracture (AO/OTA 15.2C) was simulated by means of a 5mm osteotomy gap. Specimens were cyclically tested to failure under craniocaudal cantilever bending, superimposed with bidirectional torsion around the shaft axis and monitored via motion tracking.
RESULTS
Initial construct stiffness was significantly higher in Group 2 (9.28 ± 4.40 N/mm) compared to Group 1 (3.68 ± 1.08 N/mm), p=0.003. The amplitudes of interfragmentary motions in terms of axial and shear displacement, fracture gap opening and torsion, over the course of 12,500 cycles were significantly higher in Group 1 compared to Group 2, p≤0.038. Cycles to 2mm shear displacement were significantly lower in Group 1 (22792 ± 4346) compared to Group 2 (27437 ± 1877), p=0.047.
CONCLUSION
From a biomechanical perspective, low-profile 2.5/2.0 dual plates can be considered as a useful alternative for diaphyseal clavicle fracture fixation especially in less common unstable fracture configurations. 2.7 single superior variable angle locking plates and can therefore be considered as a useful alternative for diaphyseal clavicle fracture fixation especially in less common unstable fracture configurations
Fully automatic algorithm for detecting and tracking anatomical shoulder landmarks on fluoroscopy images with artificial intelligence.
Get PDFOBJECTIVE
Patients with rotator cuff tears present often with glenohumeral joint instability. Assessing anatomic angles and shoulder kinematics from fluoroscopy requires labelling of specific landmarks in each image. This study aimed to develop an artificial intelligence model for automatic landmark detection from fluoroscopic images for motion tracking of the scapula and humeral head.
MATERIALS AND METHODS
Fluoroscopic images were acquired for both shoulders of 25 participants (N = 12 patients with unilateral rotator cuff tear, 6 men, mean (standard deviation) age: 63.7 ± 9.7 years; 13 asymptomatic subjects, 7 men, 58.2 ± 8.9 years) during a 30° arm abduction and adduction movement in the scapular plane with and without handheld weights of 2 and 4 kg. A 3D full-resolution convolutional neural network (nnU-Net) was trained to automatically locate five landmarks (glenohumeral joint centre, humeral shaft, inferior and superior edges of the glenoid and most lateral point of the acromion) and a calibration sphere.
RESULTS
The nnU-Net was trained with ground-truth data from 6021 fluoroscopic images of 40 shoulders and tested with 1925 fluoroscopic images of 10 shoulders. The automatic landmark detection algorithm achieved an accuracy above inter-rater variability and slightly below intra-rater variability. All landmarks and the calibration sphere were located within 1.5 mm, except the humeral landmark within 9.6 mm, but differences in abduction angles were within 1°.
CONCLUSION
The proposed algorithm detects the desired landmarks on fluoroscopic images with sufficient accuracy and can therefore be applied to automatically assess shoulder motion, scapular rotation or glenohumeral translation in the scapular plane.
CLINICAL RELEVANCE STATEMENT
This nnU-net algorithm facilitates efficient and objective identification and tracking of anatomical landmarks on fluoroscopic images necessary for measuring clinically relevant anatomical configuration (e.g. critical shoulder angle) and enables investigation of dynamic glenohumeral joint stability in pathological shoulders.
KEY POINTS
• Anatomical configuration and glenohumeral joint stability are often a concern after rotator cuff tears. • Artificial intelligence applied to fluoroscopic images helps to identify and track anatomical landmarks during dynamic movements. • The developed automatic landmark detection algorithm optimised the labelling procedures and is suitable for clinical application
Effect of analysis software program on measured deviations in complete arch, implant-supported framework scans.
Get PDFSTATEMENT OF PROBLEM
Implementation of fabrication trueness analysis by using a recently introduced nonmetrology-grade freeware program may help clinicians and dental laboratory technicians in their routine practice. However, knowledge of the performance of this freeware program when compared with the International Organization for Standardization recommended metrology-grade analysis software program is limited.
PURPOSE
The purpose of this in vitro study was to evaluate the effect of an analysis software program on measured deviations in the complete arch, implant-supported framework scans.
MATERIAL AND METHODS
A total of 20 complete arch, implant-supported frameworks were fabricated from a master standard tessellation language (STL) file from either polyetheretherketone (PEEK) or titanium (Ti) (n=10). All frameworks were then digitized by using different scanners to generate test STLs. All STL files were imported into a nonmetrology-grade freeware program (Medit Link) and a metrology-grade software program (Geomagic Control X) to measure the overall and marginal deviations of frameworks from the master STL file by using the root mean square (RMS) method. Data were analyzed by using the two 1-sided paired t test procedure, in which 50 µm was considered as the minimal clinically meaningful difference (α=.05).
RESULTS
When overall RMS values were considered, the nonmetrology-grade freeware program was not inferior to the metrology-grade software program (P.05).
CONCLUSIONS
The use of the tested nonmetrology-grade freeware program resulted in overall deviation measurements similar to those when a metrology-grade software program was used. The freeware program was inferior when marginal deviations were analyzed on E4 scans of a PEEK framework, which was the only scanner-material pair that led to a significant difference, among the 15 pairs tested
Definitions of histological abnormalities in inflammatory bowel disease: an ECCO position paper.
Get PDFHistological assessment of endoscopic biopsies in inflammatory bowel disease [IBD] plays an important role in clinical management, investigative studies, and clinical trials. Scoring schemes consisting of multiple histological items and offering considerable precision are widely available. However, definitions of histological abnormalities are often inconsistent. Furthermore, interobserver variability for their recognition and assessment may be high. The European Crohn's and Colitis Organisation [ECCO] formed an expert panel to explore definitions of histological abnormalities in IBD, with the aim of improving the quality of diagnosis and facilitating development of scoring schemes. The process confirmed that the current definitions often have no evidence base and vary between sources. Using available evidence and expert knowledge, the panel produced a series of ECCO consensus position statements on histological features in IBD
Between information campaign and controversy: a quantitative newspaper content analysis about COVID-19 vaccination in Switzerland and Austria.
No full textAIMS
Because media portrayal reflects and shapes public opinion and health policy, investigating news coverage of public health issues is highly relevant for public health research and practice. Addressing a topical issue, this study investigated how newspaper coverage framed COVID-19 vaccines in Austria and German-speaking Switzerland and how it developed over time.
METHODS
A quantitative newspaper content analysis of six newspapers from Austria and German-speaking Switzerland published between January 1 and 31, 2022 was conducted. Frames were identified for each country separately through hierarchical cluster analysis (Ward's method) based on frame elements.
RESULTS
Four frames were identified in both countries: (1) Evaluating new vaccines, (2) Discussing mandates, (3) Promoting vaccination, (4) Mentioning vaccines. In Frames 1 (Switzerland 86.4%, Austria 93.3%) and 3 (Switzerland 92.7%, Austria 98.9%), most articles included vaccine-endorsing statements, with Swiss coverage including additional negative statements more often than Austrian coverage (43.2%/44.6% vs 4.0%/3.3%). Frame 2 was closely linked to vaccine skepticism only in Austria and contained more evaluative statements in Austrian newspapers (25.4% endorsing, 35.4% rejecting; in Switzerland 14.5%/18.1%). The Austrian tabloid Kronen Zeitung published most articles (497/1091, 45.6%).
CONCLUSIONS
The commercialized and comparatively high share of tabloid news coverage in Austria may have contributed to oversimplified and polarizing COVID-19 vaccine debates in this context. Insufficiently balanced and adequate information may contribute to a loss of public trust in vaccination and may therefore affect vaccination uptake. Authorities and public health professionals should consider this effect when designing information campaigns
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