Controlled nanostructrures formation by ultra fast laser pulses for color marking.

Precise nanostructuration of surface and the subsequent upgrades in material properties is a strong outcome of ultra fast laser irradiations. Material characteristics can be designed on mesoscopic scales, carrying new optical properties. We demonstrate in this work, the possibility of achieving material modifications using ultra short pulses, via polarization dependent structures generation, that can generate specific color patterns. These oriented nanostructures created on the metal surface, called ripples, are typically smaller than the laser wavelength and in the range of visible spectrum. In this way, a complex colorization process of the material, involving imprinting, calibration and reading, has been performed to associate a priori defined colors. This new method based on the control of the laser-driven nanostructure orientation allows cumulating high quantity of information in a minimal surface, proposing new applications for laser marking and new types of identifying codes.

Prospective trial of infrapopliteal artery balloon angioplasty for critical limb ischemia: angiographic and clinical results.

PURPOSE: To evaluate the safety and efficacy of infrapopliteal percutaneous transluminal angioplasty (PTA) as a primary treatment of chronic critical limb ischemia in a prospective trial. MATERIALS AND METHODS: Infrapopliteal PTA was performed on 72 limbs of 60 patients (mean age, 72 y; range, 38-92 y) and patients were followed for 12-24 months. RESULTS: The primary angiographic success rate for the stenoses was 84% (102 of 121) and that for the occlusions was 61% (41 of 67) with corresponding restenosis rates of 32% and 52% at follow-up angiography performed a mean of 10 months after primary PTA. The rate of major complications was 2.8% (access site pseudoaneurysms in two patients). The primary clinical success was 63% (45 of 72). A 48% cumulative primary patency rate, a 56% secondary patency rate, and a 80% cumulative limb salvage rate were registered at 18 months, as determined with use of Kaplan-Meier analysis. Lack of angiographic improvement at the site of the most severe ischemia and renal insufficiency (serum creatinine level > 130 micromol/L) were independent predictors of poorer long-term clinical results, as determined with use of Cox multiple regression analysis. CONCLUSIONS: Infrapopliteal PTA is a feasible primary treatment of chronic critical limb ischemia with moderate primary angiographic and clinical success, a low complication rate, and a cumulative limb salvage rate comparable with surgical techniques.

Angiographic characteristics of symptomatic recurrent disease after infrainguinal percutaneous transluminal angioplasty.

PURPOSE: To evaluate the angiographic patterns of clinically manifest recurrent disease after infrainguinal percutaneous transluminal angioplasty (PTA) of stenoses and total occlusions. METHODS: Among 326 infrainguinal PTAs on 263 consecutive patients, selective angiography was performed on 61 limbs of 52 patients 1-60 months after the primary intervention because of clinically suspected recurrent disease. Lesion-specific and patient-related factors were analyzed for 75 angiographically confirmed recurrent lesions in 57 limbs of 48 patients. RESULTS: Recurrent disease was more frequently a stenosis when the original target lesion was a stenosis (92%, 44/48) than when the original lesion was a total occlusion (59%, 16/27; p < 0.001). When the original target lesion was a stenosis, the total length of the recurrent disease was longer than that of the original lesion [3.9 +/- 3.9 cm (mean +/- standard deviation) vs 2.8 +/- 2.7 cm; p = 0.03], while in the subgroup of original total occlusions the length of the recurrent lesion was shorter than that of the original occlusion (7.1 +/- 5.0 cm vs 9.9 +/- 6.9 cm; p = 0.02). Half the restenosis (22/44) extended beyond one or both ends of the original stenosis and 38% (6/16) of the reocclusions extended beyond the distal end of the original occlusion. CONCLUSIONS: The type of recurrent disease depends on the original lesion type and the restenotic lesion frequently extends beyond one or both ends of the original target lesion.

Comparison of iodixanol 270 with iohexol 300 in infrapopliteal arteriography. Digital densitometric analysis of angiographic opacification.

PURPOSE: To compare iodixanol 270 mg I/ml with iohexol 300 mg I/ml in infrapopliteal arteriography by measuring digital densitometric vessel opacification and by visually assessing angiographic enhancement. MATERIAL AND METHODS: In a double-blind, dual-balanced, 4-sequence cross-over design, 50 claudicant patients received two contrast media injections (10 min interval) in the superficial femoral artery. Digital angiography was performed at 8 frames/s and time-density curves with a circular region of interest over a distal calf artery were generated. A mixed, linear model was used to identify effects influencing the density measurements. Subjective evaluation of the image quality was made independently by two observers. RESULTS: No statistically significant difference between the contrast media was revealed in the analysis of the densitometric measurements (p=0.14) nor in the subjective visual evaluation (p=0.74). However, the mean density at the time of maximum opacification was higher after the first injection than that after the second injection (p=0.02). There was a tendency towards lower intensity of warmth during injection of iodixanol 270 than during injection of iohexol 300. CONCLUSION: In patients with severe occlusive atherosclerotic disease, iodixanol yielded the same image quality as iohexol in infrapopliteal arteriography, in spite of the 30 mg I/ml lower iodine concentration.

Brachial artery access for percutaneous renal artery interventions.

PURPOSE: To evaluate the suitability of transbrachial access for endovascular renal artery interventions. METHODS: During 37 consecutive endovascular renal artery interventions, the transbrachial approach was used on nine patients (mean age 63 years; range 41-76 years) for 11 renal artery procedures on native kidneys and one percutaneous transluminal angioplasty (PTA) on a transplanted kidney. The reason for using transbrachial access was a steep aorta-renal angle in five, and severe aorta-iliac atherosclerosis in the remaining patients. In addition to the intervention catheter in the left brachial artery, an additional nonselective catheter for controlling the procedure was inserted transfemorally (six patients) or via the contralateral brachial artery. RESULTS: Eleven interventions (six PTAs, five stents) were successfully completed. The one failure resulted from impenetrable subclavian artery stenosis. The only major complication was a brachial artery pseudoaneurysm requiring surgical treatment. CONCLUSION: Transbrachial access is an effective and relatively safe technique for renal artery interventions when transfemoral access is not possible.

Percutaneous transluminal angioplasty in femoral artery occlusions: primary and long-term results in 107 claudicant patients using femoral and popliteal catheterization techniques.

To assess the impact of percutaneous transluminal angioplasty (PTA) of occluded femoral arteries, a prospective study of 107 claudicant patients was performed. A total of 117 limbs were treated and were followed for 1-36 months; the mean length of treated occlusions was 7.4 cm (range 2-25 cm). Eighty-nine recanalizations were performed using antegrade femoral and 28 using the retrograde popliteal catheterization technique. With logistic regression a short length of occlusion correlated favourably with early success. Including rePTAs and applying standardized criteria, survival analysis with the Kaplan-Meier method revealed a 3-year secondary patency rate of 55% for all the treated limbs. The following factors had negative influence on primary patency after successful recanalization; presence of soft thrombotic material in the recanalized artery segment and the presence of focal dissections after PTA. In univariate and multiple logistic regression analysis, male gender and a lesser extent of the atherosclerotic disease (assessed by the number of diseased vessels in the treated limb) correlated with a lower frequency of PTA procedure complications. There was no statistically significant difference in the complications, in the primary success or in the long-term results using either the femoral or popliteal route. However, the popliteal approach improved the early success of the originally antegrade access group by 6% and increased by about one-fifth the number of patients considered technically feasible for PTA in femoral artery occlusions. PTA can be used in femoral artery occlusions up to 10 cm long and it is especially suitable in femoral artery occlusions not exceeding 5 cm in length. PTA can be tried in femoral artery occlusions exceeding a length of 10 cm if operative treatment is not suitable.

Clot formation in angiographic catheters--an in vitro comparative study. Effects of heparin and protein coating of the catheter.

Clot formation was compared in 6 brands of angiographic catheters, each of which was tested in 3 states: untreated, heparinized, and albumin-coated. Forty-six samples of each brand in each state (in total 828) were filled with blood from 23 donors and incubated at +37 degrees C for 5 or 15 min. Physiologic saline was then injected through the catheters at a flow rate of 5 and 50 ml/s, respectively, and any expelled clots identified on a filter. Heparinization reduced the number of clotted catheters at 5 min, but not at 15 min. The only significant difference related to catheter brands was found between the heparinized nylon and polyurethane catheters at 5-min incubation with fewer clotted polyurethane catheters. This difference was not found between the same materials made by two other manufacturers. Albumin coating had no effect on clot formation, but clots were more easily expelled by low-flow injections in albumin-coated and, to a lesser degree, in heparinized than in untreated catheters.