Experimental Research On The Placement Of New-type Intrapleural Guide Wires Through Percutaneous Puncture For Preoperatively Localizing Small Pulmonary Nodules

Objective This study aims to the feasibility and localization rate of preoperative localization of small pulmonary nodules through percutaneously puncturing and placing new-type intrapleural guide wires.Methods Part 1: Build the inflated lung model with 6 isolated pig lungs.Inject the prepared human adhesive fibrin into the isolated pig lungs to form small pulmonary nodules.Stretch the anchor to fix the guide wire made of titanium alloy in the lung tissue;surface of the wire end should be coated with Teflon hydrophilic ultra-smooth coating.Place the guide wire into the isolated pig lung near the small pulmonary nodules,shrink and inflate repeatedly the isolated pig lung,lift slightly the wire with moderate force,and observe whether the head end of the guide wire was displaced or fell off through CT scanning;shrink to collapse the isolated pig lung finally,and incise the lung along the wire to verify the location.Part 2: Puncture skin to inject biological glue into the living lungs of 2 Guangxi ba-ma mini pigs to form the artificial small pulmonary nodule models,puncture skin to place the guide wire near the artificial small pulmonary nodules of living pig lungs under the guidance of CT,and locate the tail end of the wire in the pleural cavity or in the thoracic wall less than 0.5cm from the visceral pleura.Based on the artificial pneumothorax technology,compress and shrink the living pig lung where the guide wire was placed to simulate the collapse process of lung in the thoracoscopic surgery,observe whether the guide wire was in place through re-examination by CT,remove the lung tissue with artificial small pulmonary nodules and guide wire in the video-assisted thoracoscopic surgery for experimental pigs,slit the lung along the wire to find the head end of the wire and small pulmonary nodules,and verify the location.Results Part 1: Succeed in building the inflated lung model with 6 isolated pig lungs,and form 9 small pulmonary nodules.Small pulmonary nodules were 2~5cm from surfaces of the pig lungs,with the mean value of(3.8±0.9)cm;diameters of small pulmonary nodules were 0.8~2.5cm,with the mean value of(1.5±0.5)cm;CT scanning displayed clearly that the placed head ends(end V)of the guide wires were located0.2~1.3cm around the artificial small pulmonary nodules,with the mean value of(0.7±0.3)cm;it's visible that the V-shaped barb was stretched,and the tail end waslocated on the surface of the inflated isolated pig lung.After these lungs were incised,it's visible that the head ends of all guide wires were located 0.2~1.3cm from the nodules of the isolated pig lungs,with the mean value of(0.7±0.3)cm.The localization rate was 100%.Part 2: 19 small pulmonary nodules were formed with the 2experimental pigs.Small pulmonary nodules were 2~5cm from the visceral pleura,with the mean value of(3.3±0.9)cm;diameters of small pulmonary nodules were 0.7 ~2.3cm,with the mean value of(1.4±0.5)cm.The guide wires were successfully placed for the 19 small pulmonary nodules under the guidance of CT,taking 18.0~28.0min(with the mean value of(21.7±2.8)min).Through CT scanning,it showed that the head ends of wires were 0.2~1.2cm around the small pulmonary nodules,with the mean value of(0.6±0.3)cm;and it's visible that the V-shaped barb was stretched.Tail ends of2 guide wires were in the muscle thoracic wall 0.5cm from the visceral pleura,and tail ends of other 17 wires were in the pleural cavity.Thoracocentesis pumping should be conducted,as mild pneumothorax was found through CT scanning after two wires were located;without special processing for other wires,there was relatively obvious splinter hemorrhage of the lung after one wire was located.And there was no obvious progress.Through VATS: Tail ends of wires could be displayed clearly after pulmonary collapse.After the lung tissue was removed,incise the lung along edge of the wire,during which one wire fell off,and the small pulmonary nodules could still be found;and other 18 artificial small nodules were found in the lung along the wires.The head ends of the guide wires were located 0.2~1.2cm around the artificial small pulmonary nodules,with the mean value of(0.6±0.3)cm,The localization rate of the guide wires to the small pulmonary nodules was 100%.Conclusion1.It is a kind of minimally invasive and effective molding method to make models of small pulmonary nodules in the pig lungs under the guidance of CT.2.The new-type intrapleural guide wire placed through percutaneous puncture under the guidance of CT is able to accurately and easily locate lesions,shorten the time of VATS surgery,increase the success rate of nodule removal,narrow the scope of lung tissue removal,and avoid tearing of lung tissue and interference with the pathologic result;it is a kind of effective and feasible method for preoperative localization of small pulmonary nodules.