Surgical planning with patient-specific three-dimensional printed pancreaticobiliary disease models – Cross-sectional study

2020 ◽  
Vol 80 ◽  
pp. 175-183 ◽  
Author(s):  
Ayse Hilal Bati ◽  
Ezgi Guler ◽  
Mehmet Asim Ozer ◽  
Figen Govsa ◽  
Kamil Erozkan ◽  
...  
2021 ◽  
Vol 11 ◽  
Author(s):  
Lucas M. Ritschl ◽  
Paul Kilbertus ◽  
Florian D. Grill ◽  
Matthias Schwarz ◽  
Jochen Weitz ◽  
...  

BackgroundMandibular reconstruction is conventionally performed freehand, CAD/CAM-assisted, or by using partially adjustable resection aids. CAD/CAM-assisted reconstructions are usually done in cooperation with osteosynthesis manufacturers, which entails additional costs and longer lead time. The purpose of this study is to analyze an in-house, open-source software-based solution for virtual planning.Methods and MaterialsAll consecutive cases between January 2019 and April 2021 that underwent in-house, software-based (Blender) mandibular reconstruction with a free fibula flap (FFF) were included in this cross-sectional study. The pre- and postoperative Digital Imaging and Com munications in Medicine (DICOM) data were converted to standard tessellation language (STL) files. In addition to documenting general information (sex, age, indication for surgery, extent of resection, number of segments, duration of surgery, and ischemia time), conventional measurements and three-dimensional analysis methods (root mean square error [RMSE], mean surface distance [MSD], and Hausdorff distance [HD]) were used.ResultsTwenty consecutive cases were enrolled. Three-dimensional analysis of preoperative and virtually planned neomandibula models was associated with a median RMSE of 1.4 (0.4–7.2), MSD of 0.3 (-0.1–2.9), and HD of 0.7 (0.1–3.1). Three-dimensional comparison of preoperative and postoperative models showed a median RMSE of 2.2 (1.5–11.1), MSD of 0.5 (-0.6–6.1), and HD of 1.5 (1.1–6.5) and the differences were significantly different for RMSE (p < 0.001) and HD (p < 0.001). The difference was not significantly different for MSD (p = 0.554). Three-dimensional analysis of virtual and postoperative models had a median RMSE of 2.3 (1.3–10.7), MSD of -0.1 (-1.0–5.6), and HD of 1.7 (0.1–5.9).ConclusionsOpen-source software-based in-house planning is a feasible, inexpensive, and fast method that enables accurate reconstructions. Additionally, it is excellent for teaching purposes.


2021 ◽  
Author(s):  
Yogita Gupta ◽  
Radhika Tandon

Abstract Purpose: To describe the variables that may be utilized in the optimization of three dimensional heads up surgeries (3D-HUS) for achieving better ergonomics among ophthalmic surgeons. Methods: A cross-sectional study conducted at the operating room of a tertiary eye care centre, equipped with ARTEVO 800 3D surgical microscope and display monitor. The parameters noted were: monitor height (MH), surgeon eye to floor distance (ETFD) surgeon eye to monitor distance (ETMD) (Fig. 1a) and viewing tilt (VT) angle. The neck and eye strain of the surgeon and assistant were scored as per Borg’s CR-10 scale, before and after surgeries.Results: 15 surgeries were analysed. The minimum ETMD was 51 inches and eye strain reduced with shorted ETMD. VT and ETFD was higher for right eye surgeries. The optimum MH was between 50 to 55 inches. Overall, neck strain and eye strain were in the range of 0-3 and 0-1, respectively.Conclusion: The various parameters affecting 3D image quality, neck and eye strain are: chair height, viewing tilt angle, eye centration, monitor distance, laterality of the eye and room illumination.


2021 ◽  
Author(s):  
Lotta-Maria A. H. Oksanen ◽  
Jenni Virtanen ◽  
Enni Sanmark ◽  
Noora Rantanen ◽  
Vinaya Venkat ◽  
...  

Abstract SARS-CoV-2 has been detected both in air and on surfaces, but questions remain about the patient-specific and environmental factors affecting virus transmission to the environment. Additionally, more detailed information on viral findings in air is needed. This cross-sectional study presents results from 259 air and 252 surface samples from the surroundings of 23 hospitalized and eight home-treated COVID-19 patients between July 2020 and March 2021 and compares the results between the measured environments and patient factors. The proportions of PCR-positive air and surface samples showed statistical similarity in hospital and in the home. In four cases, positive environmental samples were detected even after the patients had developed a neutralizing IgG response. SARS-CoV-2 RNA was detected in the following particle sizes: 0.65–4.7 µm, >7 µm, >10 µm, and <100 µm. Appropriate infection control against airborne and surface transmission routes is needed in both environments, even after antibody production has begun.


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