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Using 320-detector row computed tomography angiography (320-CTA) to investigate the arterial supply for the toe flaps, namely the anatomical characteristics of the dorsalis pedis artery (DPA), the first dorsal metatarsal artery (FDMA), and the arteries of the first toe web space (AsFTWS). This was a prospective study on CTA of 72 intact feet of 36 Vietnamese adults who had sequelae of thumb or metacarpal hand amputation, from June 2017 to December 2019, then preoperative CTA images were compared with surgical findings on 31 feet of 29 patients. 320-CTA was able to investigate the DPA, FDMA, and AsFTWS in 100% of cases. DPA was absent in 6.9% of cases. The average diameters at its origin and termination were 3.22 and 2.56 mm, respectively. For FDMA, the rates of Gilbert type I, II, and III were 52.8%, 18.1%, and 29.2%; the average diameters at its origin and termination were 1.98 and 1.67 mm, respectively. At the first toe web space, FDMA was dominant in 54.2% of cases; the first plantar metatarsal artery (FPMA) was dominant in 29.2% of cases; both arteries were equally dominant in 16.6%. The average diameter at the origin of the lateral plantar digital artery of the great toe was 1.48 mm, of the medial plantar digital artery of the second toe was 1.21 mm. Preoperative CTA images resembled the surgical findings in all cases. The survival rate of toe flaps was 100%. The 320-CTA provided proper preoperative images in two and three dimensions, and helped surgeons to establish a preoperative surgical plan, thus increasing the success rate of toe transfer surgery.

International audience; Passive plasmonic metasurfaces enable image multiplexing by displaying different images when altering the conditions of observation. Under white light, three-image multiplexing with polarization selective switching has been recently demonstrated using femtosecond-laser-processed random plasmonic metasurfaces. Here, the implementation of image multiplexing is extended, thanks to a color search algorithm, to various observation modes compatible with naked-eye observation under incoherent white light and to four-image multiplexing under polarized light. The laser-processed random plasmonic metasurfaces enabling image multiplexing exhibit self-organized patterns that can diffract light or induce dichroism through hybridization between the localized surface plasmon resonance of metallic nanoparticles and a lattice resonance. Improved spatial resolution makes the image quality compatible with commercial use in secured documents, as well as the processing time and cost thanks to the use of a nanosecond laser. This high speed and flexible laser process, based on energy efficient nanoparticle reshaping and self-organization, produces centimeter-scale customized tamper-proof images at low cost, which can serve as overt security features.

In this study, we observed the color performance of an organic light-emitting diode (OLED) as functions of the optical lengths of the inorganic layers on the parameter space map in order to obtain the goal of increased color performance. To design the dominant wavelength and the bandwidth of the OLED, we employed the finite-difference time-domain method to calculate the optical characteristics of the light emitted from the emitting material layer. We only handled inorganic layers such as the cathode layer, the capping layer, and the indium-tin oxide layer in OLED layers to avoid changing the electro-optical characteristics of the light emerging from the organic layers. With this simple technique, we established the optimal conditions for the optical length of each layer without any intrusion into the organic layers. In this study, we demonstrated the parameter space map for a red OLED that exhibits a 24-nm bandwidth with a peak emission at wavelength λ = 618 nm. We verified the proposed parameter space method by experimentation and present the experimental results in this paper.

Summary Background Reconstruction for proximal thumb amputation at the carpometacarpal (CMC) joint level is extremely challenging. All thenar muscles are lost and other fingers might be lost or injured. Transmetatarsal trimmed great toe (TGT) transfer may be an option in such cases. Methods Between 2012 and 2018, 11 patients who had amputation of the thumb at the CMC joint level were reconstructed by transmetatarsal TGT transfer in a single stage. There were seven cases in which the right hand was affected and four cases in which the left hand was affected. Three cases involved a contracture scar at the thumb stump and required web space reconstruction. Average follow-up was 33.9 months (range: 12–76 months) Results All toe transfers survived. The average of static two-point discrimination (S2PD) was 14.6 mm; the average scores of the Quick Disabilities of the Arm, Shoulder, and Hand (quickDASH) questionnaire and the Michigan Hand Outcomes Questionnaire (MHQ) were 18.6 and 73.8, respectively. Two cases did not achieve opposition due to mispositioning of the neothumb. In nine cases achieving opposition, the Kapandji score ranged from 4 to 9, pinch ranged from 3 to 11 lbs, and grip ranged from 15 to 86 lbs. In the donor foot, three patients had neuroma and two had a new callus on the palmar side of the second and third metatarsal heads. The average foot and ankle disability index score was 91.6. Conclusion Single-staged transmetatarsal TGT transfer is safe and useful for thumb reconstruction at the CMC joint level. This reconstructive method is suitable for manual workers, especially in the developing countries.