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961.
After total laryngectomy with or without partial pharyngectomy, the remaining pharyngeal defect can be repaired either by primary closure or with additional tissue, depending on the amount of pharyngeal tissue remnant available. The aim of this study was to determine the minimum width of the pharyngeal remnant that could be safely closed primarily without causing difficulty in swallowing. A total of 52 consecutive patients who underwent total laryngectomy were entered into the study. The relaxed and stretched widths of the pharyngeal remnant were measured after removal of the specimen. The widths of the pharyngeal mucosa ranged from 1.5 to 5.0 cm relaxed (mean, 3.24 cm) and from 2.5 to 8.0 cm stretched (mean, 4.83 cm). All neopharynx was reconstructed by closing the pharynx primarily. Seven of the 52 patients developed recurrent tumor with concomitant dysphagia. Two of the 45 patients without recurrence presented with acute dysphagia from food bolus obstruction, and 1 patient developed benign inflammatory stricture following an episode of fish-bone impaction. The narrowest widths of the pharyngeal remnant in this group of 45 were 1.5 cm relaxed and 2.5 cm stretched. As these patients do not have swallowing difficulty, we conclude that in the absence of tumor recurrence, this amount of residual pharyngeal tissue is sufficient both for primary closure of the pharynx and in restoring swallowing function. 相似文献
962.
Xin Tang Matthew M. Ackerman Guohua Shen Philippe Guyot‐Sionnest 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(12)
Electronic eye cameras are receiving increasing interest due to their unique advantages such as wide field of view, low aberrations, and simple imaging optics compared to conventional planar focal plane arrays. However, the spectral sensing ranges of most electronic eyes are confined to the visible, which is limited by the energy gaps of the sensing materials and by fabrication obstacles. Here, a potential route leading to infrared electronic eyes is demonstrated by exploring flexible colloidal quantum dot (CQD) photovoltaic detectors. Benefitting from their tunable optical response and the ease of fabrication as solution processable materials, mercury telluride (HgTe) CQD detectors with mechanical flexibility, wide spectral sensing range, fast response, and high detectivity are demonstrated. A strategy is provided to further enhance the light absorption in flexible detectors by integrating a Fabry–Perot resonant cavity. Integrated short‐wave IR detectors on flexible substrates have peak D* of 7.5 × 1010 Jones at 2.2 µm at room temperature and promise the development of infrared electronic eyes with high‐resolution imaging capability. Finally, infrared images are captured with the flexible CQD detectors at varying bending conditions, showing a practical approach to sensitive infrared electronic eyes beyond the visible range. 相似文献