The authors report on the management of 33 patients with penetrating venous injuries, 25 due to gunshot wounds and 8 due to stab wounds. During the period of this study we treated 35 venous injuries and two patients, both following femoral artery and vein repairs and limb salvage were lost to follow-up and are excluded. Thirty-two had associ ated thoracic, intraabdominal, or arterial injuries. Duplex imaging was performed in 14 patients and venography in 12. They assessed all 27 survivors for postoperative sequelae. Mean follow-up time was twenty months, ranging from three months to three years. Four patients had suprarenal inferior vena cava injuries. All 4 underwent repair and 2 survived. Seven others had infrarenal vena cava injuries. Three of 5 survived following repair and the other 2 survived after caval ligation. Three patients had iliac vein injuries. Two died after repair and 1 survived with ligation. Seventeen patients had injuries of the femoral vein. Thirteen underwent repair, 7 of whom remained patent. Four had ligations performed. There were 2 injuries of the popliteal vein; both were repaired, but neither remained patent. All 19 patients with femoral and popliteal vein injuries survived with limb salvage. Postoperative sequelae (persistent edema, skin discoloration) were observed in 4 failed venous repairs—2 femoral and 2 popliteal. Ligation of the infrarenal vena cava and iliac veins, as compared with repair, yielded a greater patient salvage rate. There was no increased morbidity with ligation of the femoral veins, which was undertaken only on unstable patients.

The linear and nonlinear optical properties of Ag/Au bilayer metallic thin films with a total thickness of around 20 nm and with different Ag/Au mass-thickness ratios were studied. This study shows that the spectral dispersion of the effective refractive index of bilayer films can be tuned by controlling the mass-thickness ratio between Au and Ag. Improvement of the figure-of-merit for potential plasmonic applications and linear optical filters in the visible spectral range are reported and discussed. The nonlinear optical properties of bilayer metal films studied using femtosecond white-light continuum pump-probe experiments are also shown to be tunable with this ratio. The nonlinear change of optical path length is extracted from the pump-probe data and agrees with simulated values derived from a combination of the two-temperature model, describing the ultrafast electron heating dynamics, and a physical model that describes the dielectric permittivity of Au as a function of electron and lattice temperature.

A novel nonlinear mirror structure is presented. A 23 nm-thick Au thin film separated from a 100 nm-thick Ag film by a dielectric spacer is used to drive the nonlinear optical response of the mirror. The linear and nonlinear optical properties of the mirror can be tuned by optimizing its layer thickness distribution. A figure-of-merit for the change in reflectance is derived for the nonlinear mirror and the nonlinear refractive index change of the Au layer is shown to be significantly enhanced in the mirror structure. The ultrafast reflectance change of the nonlinear mirror, studied using femtosecond white-light continuum pump-probe experiments, shows an extremely large magnitude and is both spectrally and angularly broad in the visible range.

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