1. An injectable aqueous composition in the form of a gel based on hyaluronic acid or one of its salts, one or more polyols and lidocaine, thermally sterilized for cosmetic or therapeutic purposes, as a result of which it has improved viscoelastic rheological properties and improved in vivo persistence. 2. An injectable aqueous composition according to claim 1, characterized in that the sterilization is carried out with moist heat. An injectable aqueous composition according to claim 1, characterized in that the concentration of hyaluronic acid or one of its salts is from 0.01 mg / ml to 100 mg / ml, and the molecular weight of hyaluronic acid or one of its salts is from 1000 daltons to 10 × 10 daltons. 4. An injectable aqueous composition according to claim 1, characterized in that the concentration of the polyol is from 0.0001 to 100 mg / ml. An injectable aqueous composition according to claim 1, characterized in that the concentration of lidocaine is from 0.0001 to 50 mg / ml. An injectable aqueous composition according to claim 1, characterized in that the gel based on hyaluronic acid or one of its salts is non-crosslinked. An injectable aqueous composition according to claim 1, characterized in that the gel based on hyaluronic acid or one of its salts is crosslinked. An injectable aqueous composition according to claim 7, characterized in that the gel based on hyaluronic acid or one of its salts is crosslinked with or without the use of one or more other polysaccharides of natural origin. An injectable aqueous composition according to claim 7, characterized in that the gel based on hyaluronic acid or one of its salts is crosslinked with bifunctional or polyfunctional substances selected from ep1. Применяемая в косметических или терапевтических целях инъецируемая водная композиция в форме геля на основе гиалуроновой кислоты или одной из ее солей, одного или нескольких полиолов и лидокаина, подвергнутая тепловой стерилизация, в результате чего она имеет улучшенн
