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Biomedical subjects

G Boussignac

Publications and source records attributed to G Boussignac.

32 records · Page 2Linked to original sources
PubMed1989

[Percutaneous angioplasty using spectroscopy-guided pulsed laser].

Percutaneous laser angioplasty was performed in 19 patients with calcified and non-calcified occlusions (4-25 cm long) of the superficial femoral artery, using a pulsed dye laser at 480 nm and a pulse duration of 2 microseconds per pulse. The treatment laser was guided by a 325 nm diagnostic laser that induced tissue fluorescence. The laser system operated through a single 200 microns optical fiber. Computer spectral analysis of the tissue fluorescence located at the distal end of the fiber tip directed emission of the treatment laser only at the atheroma without affecting the arterial wall. A successful primary laser recanalization was obtained in all cases and was followed by balloon dilation in all but one patient. One mechanical perforation and 2 mechanical arterial dissections by the fiber, and 1 perforation and 1 dissection by the guide wire occurred, but no complications due to the treatment or diagnostic laser were observed. The safety of the procedure seemed to be enhanced by the spectroscopic guidance system which enabled plaque recognition. The pulsed dye treatment laser was well tolerated and effective even in heavily calcified arteries.

Adult↗
PubMed1989

[Myocardial protection by coronary autotransfusion during angioplasty].

Coronary autologous blood perfusion may protect the myocardium against ischemia during arterial occlusion due to balloon inflation. During balloon inflation, arterial blood was perfused via the balloon catheter in 19 patients with single proximal severe left anterior descending artery stenosis and normal left ventricular function. Blood was perfused using a contrast medium injector at a flow rate of 40 ml/min. The balloon was maintained inflated for 60 seconds at 6 atmospheres. Two inflations were performed with perfusion and 2 without. Myocardial ischemia was assessed by ST elevations on both the peripheral and intracoronary ECGs, changes in left ventricular systolic and end diastolic pressures and peak positive and negative dP/dt. A positive response was obtained in 11 patients. In 5 patients, the myocardial ischemia induced by dilatation was not alleviated by the perfusion and in 3 patients ischemia was increased by perfusion. In conclusion, ischemia is inconsistently reduced by autologous blood perfusion and its adverse effect in some patients could limit its use.

Aged↗
PubMed1986

Laser angioplasty of arterial stenoses.

To establish the optimal conditions for recanalization of obstructed arteries without damage to vessel walls, an Nd-YAG laser coupled to a 0.2-mm-diameter optical fiber was used on obstructed human cadaver coronary and peripheral arteries and on popliteal arteries in amputated limbs. Vaporization of atheromatous plaques was consistently obtained with energy of 360-600 J and a diluted blood perfusate (3 g/100 ml hemoglobin) at a rate of 30 ml/min. The arterial wall was protected from thermal injury by inserting the optical fiber into an inflated balloon catheter and by cooling the system with the perfusate. Since recanalization of occluded arteries was consistently obtained without damage to the arterial wall or debris and thin and flexible optical fibers were easy to guide in the arteries, percutaneous transluminal Nd-YAG laser angioplasty was used in obstructed femoral and popliteal arteries in 12 patients. The first trials in man with Nd-YAG laser showed the method to be feasible, effective, and at low risk, although further studies are required to improve penetration of the obstruction and increase the diameter tunnel.

Angioplasty, Balloon↗
PubMed1986

Histopathology after Nd-YAG laser percutaneous transluminal angioplasty of peripheral arteries.

Laser recanalization of occluded femoral or popliteal arteries was performed in 12 patients using a continuous wave neodymium yttrium aluminum garnet (Nd-YAG) laser. The histologic findings of the laser-irradiated arterial segments in two of these patients are reported. The specimens were obtained 2 and 4 weeks after the laser procedure. The laser-irradiated vessel in Patient 1 had been partially recanalized with reduction of the atherosclerotic occlusion from 3 to 1 cm. The lased arterial lumen manifested thermal injury to the inner quarter of the arterial wall with vacuolization and a rim of carbonization occupying 10% of the width of the arterial wall, but without thrombus formation. Histologic examination in Patient 2 revealed no fibrin deposits, atherosclerotic debris or thrombi at the intimal arterial edge. At the crater site, thermal injury was apparent with vacuolization of the intimal fibrous tissue. The histologic sections obtained 4 weeks after the procedure revealed new fibrous intimal tissue without endothelialization in some of the heavily calcified tissue sections. Where the plaques were noncalcified, reendothelialization was noted with only minimal damage to the surrounding tissue. No medial or elastic fiber disruption was seen, and no aneurysmal dilation had occurred. Intimal splitting with a cleft between the tunica media and the intima was noted at the site of previous balloon angioplasty. In conclusion, the follow-up histologic findings 2 and 4 weeks after laser angioplasty in two patients using a specially designed catheter delivery system and cooling blood perfusate revealed thermal injury to the inner quarter of the arterial vessel wall and no evidence of thrombus formation.

Aged↗
PubMed1986

[Arterial recanalization using the laser. A technic for the future?].

On the basis of two years' experience, a technique for the use of percutaneous endoluminal continuous emission Nd-YAG laser has been developed for arterial recanalisation. The effectiveness of this type of laser has been demonstrated in a large number of clots and atheromatous plaques, including calcified plaques. A balloon catheter gives a coaxial position of the fiber in center of the artery. Infusion of a blood solution containing 3 g of haemoglobin/100 ml at a rate of 20 ml/minute limits the thermal parietal lesions, improves the conditions of laser treatment and eliminates any risk of arterial perforation. No embolic debris is collected down-stream. Recanalisation of long arterial segments in amputated legs was performed prior to the human application. Ten patients have been treated with no mortality and virtually no morbidity. The narrowness of the reformed arterial lumina resulted in early re-thrombosis in the first 5 cases, requiring balloon modelling to ensure patency with a follow-up of 1 to 3 months in the 5 following patients.

Aged↗
PubMed1985

[Arterial disobliteration by the laser].

In order to determine the optimal conditions for disobliteration of occluded arteries without damaging the arterial wall, the effects of a Nd-YAG laser connected to a 0.2 mm diameter fibre optic system were studied on post-mortem coronary arteries and popliteal and tibial arteries of amputated limbs. Vaporisation of atheromatous plaques was consistently obtained with energies of 300 to 600 joules associated with perfusion of the vessel with dilated blood (3 g/100 ml of haemoglobin) at a flow rate of 20 ml/min. Protection of the arterial wall was ensured by introducing the fibre aortic system through a balloon catheter and by cooling with the perfusion liquid. The reproducibity of these results in the absence of major arterial wall damage, and the facility of manipulation of the fibre optic system due to its flexibility and narrow diameter, encouraged us to use this method clinically. The first three applications on peripheral arteries (femoral and popliteal arteries) confirmed that this method of arterial disobliteration can be used with a certain degree of efficacy with only a slight risk of arterial perforation. Further studies are essential to improve the degree of laser penetration of the arterial obstruction and to increase the diameter of the tunnel of recanalisation.

Arterial Occlusive Diseases↗
PubMed1984

Recanalization of human arteries using Nd-YAG laser carried by optical fibre.

Nd-NAG laser carried by optical fibres 0.2 mm diameter was used in experimental studies to recanalize obstructed human cadaver arteries. Successful perforation of atheromatous plaques was obtained in all cases with a power of 12 W and a duration of exposure of 30-50 s provided that blood and not saline was used. The arterial wall was protected from injury by coaxial position of the optical fibre that was inserted into an inflated balloon catheter, and by circulating blood that cooled the system. The feasibility of guiding these devices in man was demonstrated in femoral and coronary arteries.

Arterial Occlusive Diseases↗
PubMed1984

Conditions for effective Nd-YAG laser angioplasty.

To establish the optimal conditions for recanalisation of obstructed arteries without damage to vessel walls, a Nd-YAG laser coupled to a 0.2 mm diameter optic fibre was used on obstructed human cadaver coronary and peripheral arteries and on popliteal arteries in amputated limbs. Vaporization of atheromatous plaques was consistently obtained with an energy of 360-600 J and a diluted blood perfusate (3 g/100 ml haemoglobin) at a rate of 20 ml/min. The arterial wall was protected from thermal injury by inserting the optic fibre into an inflated balloon catheter and by cooling the system with the perfusate. Since recanalisation of occluded arteries was consistently obtained without damage to the arterial wall or debris and thin and flexible optic fibres were easy to guide in the arteries, percutaneous transluminal Nd-YAG laser angioplasty was used in obstructed femoral and popliteal arteries in three patients. The first European trials in man showed the method to be feasible, effective, and harmless, although further studies are required to improve penetration of the obstruction and increase the diameter of tunnel.

Angioplasty, Balloon↗