The interventional therapy of vascular stent implantation is a popular treatment method for cardiovascular stenosis and blockage. However, traditional stent manufacturing methods such as laser cutting are complex and cannot easily manufacture complex structures such as bifurcated stents, while three-dimensional (3D) printing technology provides a new method for manufacturing stents with complex structure and personalized designs. In this paper, a cardiovascular stent was designed, and printed using selective laser melting technology and 316L stainless steel powder of 0−10 µm size. Electrolytic polishing was performed to improve the surface quality of the printed vascular stent, and the expansion behavior of the polished stent was assessed by balloon inflation. The results showed that the newly designed cardiovascular stent could be manufactured by 3D printing technology. Electrolytic polishing removed the attached powder and reduced the surface roughness Ra from 1.36 µm to 0.82 µm. The axial shortening rate of the polished bracket was 4.23% when the outside diameter was expanded from 2.42 mm to 3.63 mm under the pressure of the balloon, and the radial rebound rate was 2.48% after unloading. The radial force of polished stent was 8.32 N. The 3D printed vascular stent can remove the surface powder through electrolytic polishing to improve the surface quality, and show good dilatation performance and radial support performance, which provides a reference for the practical application of 3D printed vascular stent.
Abstract: Objective To summarize the immediate effects and the near and midterm followup results of transthoracic balloon valvuloplasty for newborns and infants with severe and critical pulmonary valve stenosis to find out an effective plan for onestop balloon valvuloplasty. Methods From March 2006 to March 2010, 32 patients including 23 males and 9 females with severe and critical pulmonary valve stenosis were treated in Fu Wai Hospital. Their age ranged from 5 days to 11 months (4.59±3.21 months). Weight of the patients ranged from 2.3 to 10.5 kg (6.48±2.05 kg). Dilatation was performed under general anesthesia with intubation and the guidance of echocardiography. During the follow-up period, all survivors had serial echocardiographic assessment to measure the transpulmonary pressure gradient (TPG) and the degree of pulmonary regurgitation. Results All operations were successful with no severe postoperative complications. Hemodynamic indexes were stable after operation with TPG lowered from from 82±27 mm Hg preoperatively to 23±12 mm Hg postoperatively (t=15.28, Plt;0.05). Only 4 patients had a TPG of more than 40 mm Hg on echocardiography before leaving the hospital. Tricuspid regurgitation was decreased significantly with 17 cases of nonregurgitation, 13 cases of light regurgitation and 2 cases of moderate regurgitation. Saturation of peripheral oxygen in all the patients increased to higher than 95%. Followup time ranged from 1 month to 4 years (16±11 months). The results of the follow-up were satisfying for all the patients. The average TPG was 17±10 mm Hg with only one above 40 mm Hg. Pulmonary valve regurgitation was found in 24 patients including 23 with light pulmonary regurgitation and 1 with moderate regurgitation. Conclusion Transthoracic balloon valvuloplasty for newborns and infants with severe and critical pulmonary valve stenosis is safe and effective.
Objective To evaluate the clinical effect of balloon dilatation in the treatment of lower urinary tract obstruction in children. Methods Twenty-six boys suffering from lower urinary tract obstruction underwent the balloon dilatation operation. These patients included 23 cases of posterior urethral valves, 2 cases of anterior urethral valves and 1 case of traumatic urinary tract stricture. Their ages ranged from 18 days to 7 years. All the patients were diagnosed by voiding cystourethrogram (VCG). Some of the boys suffered from bilateral hydronephrosis and dilated ureters. Before operation, the patients with urine retention or abnormal renal function should drain urine and correct the disorderof fluid and electrolyte. Balloon dilatation was done after their conditions were improved. During operation, ketamine anaesthesia was used, and 30% diatrizoate melglumine was used as dilatation drug. The balloon catheters which had the length of 4 cm and the diameters of 5，8，10 mm respectively were used for dilating the urethra. After operation, a Foley’s catheter was routinely indwelled. Results During procedure, compression phenomena disappeared in the course of operation. All the patients urinated normally after catheter was removed at 1 week post operatively. 6 cases received ureteral reimplantation to prevent vesioureteral reflux after 1 to 3 months. 25patients were followed up from 1 to 13 years and all patients had normal micturition and the bilateral hydronephrosis were improved. Conclusion Balloon dilatation is a safe, effective and feasible therapy for lower urinary tract obstruction in children.
Objective To evaluate the cl inical effect of percutaneous transluminal angioplasty (PTA) and PTA and stenting (PTAS) in treating multilevel arteriosclerosis obl iterans (ASO) of lower extremities. Methods Between January 2007 and October 2009, 29 cases of multilevel ASO of lower extremities were treated with PTA or PTAS. There were 17 males and 12females with an average age of 71 years (range, 56-83 years). The cl inical manifestations were l imbs numb with cold sensation, intermittent claudication (lt; 100 m), and 19 patients had rest pain. According to Fontaine stages classification, there were 7 cases of stage II, 14 cases of stage III, and 8 cases of stage IV. Concomitant diseases included hyperl ipidemia in 13 cases, diabetes in 6 cases, hypertension in 12 cases, chronic heart failure in 5 cases, chronic obstructive pulmonary disease in 3 cases, cerebral infarction in 5 cases, and toe ulcer in 15 cases. The preoperative ankle/brachial index (ABI) was 0.28 ± 0.13. Results In 3 cases of below knee lesions for the guide wire puncturing through the artery wall, 1 case gave up, and 2 cases continued recanal ized other arteries without serious bleeding compl ications. After operation, cerebral infarction occurred in 1 case, pulmonary infection in 2 cases, and groin puncture site hematoma in 2 cases. All patients were followed up 3 to 36 months. Limb skin temperature was significantly improved, and intermittent claudication disappeared or claudication distance lengthened, rest pain disappeared or significantly reduced in 27 patients (30 l imbs). The wound of amputee achieved good heal ing in 2 cases (2 l imbs). In 27 patients undergoing endovascular treatment, the postoperative ABI was 0.72 ± 0.19, showing significant difference when compared with the preoperative one (P lt; 0.05). Conclusion The PTA and PTAS treatment for multilevel ASO of lower extremities is a safe and effective option, and the short-term effect is good. Different treatments should be chosen according to the location and length of vascular occlusion.
ObjectiveTo investigate the clinical effect of No. 8 blood collection needles in connecting broken balloon tubes. MethodsThirty-six patients who underwent mechanical ventilation in the Intensive Care Unit between January 2010 and December 2013 were included as the study subjects. We divided them into two groups. Patients who had accidental rupture of balloon tube during intubation were regarded as the trial group, while those with normal ventilation were regarded as the control group, with each group having 18 patients. The trial group used No. 8 disposable blood collection needles to connect the balloon tubes. Pressure gauge produced in Germany was used to measure the balloon pressure continuously for four hours. Balloon pressure level, balloon leakage and tube dislocation within 24 hours were observed. ResultsThe balloon pressure at different time periods was not significantly different between the two groups (P > 0.05). The leakage rate and complication rate were also not significantly different between the two groups (P > 0.05). ConclusionsUsing No. 8 blood collection needles for connecting broken balloon tubes is effective, easy, and convenient, and the balloon can be maintained at a constant pressure. It solved many previous clinical problems such as high cost, high complication rate, high death rate and medical disputes.
ObjectiveTo discuss the operation skill and clinical effects of using domestic balloon-expandable Prizvalve® transcatheter "valve-in-valve" to treat the degenerated bioprosthesis in the tricuspid position.MethodsAll the admitted surgical tricuspid valve bioprosthetic valve replacement patients were evaluated by computerized tomography angiography (CTA), ultrasound, and 3D printing technology, and 2 patients with a degenerated bioprosthesis were selected for tricuspid valve "valve-in-valve" operation. Under general anesthesia, the retro-preset Prizvalve® system was implanted into degenerated tricuspid bioprosthesis via the femoral vein approach under the guidance of transesophageal echocardiographic and fluoroscopic guidance.ResultsTranscatheter tricuspid valve implantation was successfully performed in both high-risk patients, and tricuspid regurgitation disappeared immediately. The operation time was 1.25 h and 2.43 h, respectively. There was no serious complication in both patients, and they were discharged from the hospital 7 days after the operation.ConclusionThe clinical effect of the degenerated tricuspid bioprosthetic valve implantation with domestic balloon-expandable valve via femoral vein approach "valve-in-valve" is good. Multimodality imaging and 3D printing technology can safely and effectively guide the implementation of this innovative technique.
Objective To evaluate the application value of spiral CT virtual endoscopy and three dimensional imaging in fiberoptic bronchoscopic balloon dilation in patients with benign tracheobronchial stenosis. Methods Thirty-three cases of benign tracheobronchial stenosis from June 2004 to November 2008 were checked by spiral CT with airway tracheobronchial reconstruction. For the patients with indications, balloon dilatation was performed under fiberoptic bronchoscope. The three-dimensional reconstruction images were compared with the findings under bronchoscopy. And the preoperative and postoperative three-dimensional reconstruction images were compared for airway diameter. Results Three cases were found stenosis of middle lobe by CT virtual endoscopy and did not undergo balloon dilatation. The remaining 30 cases were confirmed by bronchoscopy findings similar to the images by tracheobronchial reconstruction with CT, with consistent rate of 100% . Immediate postoperative three-dimensional CTreconstruction of tracheal bronchus revealed that diameter of stenotic bronchus increased from ( 2. 7 ±1. 3) mm to ( 6. 9 ±1. 6) mmafter operation. Conclusion Multislice spiral CT virtual endoscopy is helpful in fiberoptic bronchoscopic balloon dilation in patients with benign tracheobronchial stenosis and postoperative follow-up.
ObjectiveTo evaluate the clinical efficiency of balloon occlusion of the lower abdominal aorta in blood loss control during resections of pelvic or sacral tumor. MethodsFrom April 2006 to April 2010, 24 patients diagnosed as pelvic or sacral tumor in this hospital were collected. Balloon occlusion of the lower abdominal aorta to control blood loss was used in these cases. Balloon catheters were placed via femoral artery to occlude the abdominal aorta before operation. Resections of pelvic or sacral tumors were performed after occlusion of abdominal aorta, duration no longer than 60 min per occlusion, if repeated occlusions needed, 10－15 min release in between. Results Average operative time was 153 min (range 40－245 min) and average blood loss was 310 ml (range 200－650 ml) in this series, and the procedure helped in clearly identifying the surgical margin, neurovascular structures, and adjacent organs. The blood pressure were stable in all the cases. No postoperative renal function impairment was found in all the cases, no side injuries to adjacent organs was identified. One case complicated with thrombosis in iliac artery at same puncture side was successfully treated with catheter thrombectomy. ConclusionIntraoperative abdominal aorta balloon occluding in pelvic and sacral tumor surgical operation could reduce blood loss, and improve the safety of operation.
ObjectiveTo investigate the short-term effectiveness of balloon vertebroplasty combined with short-segment pedicle screw instrumentation for the treatment of thoracolumbar burst fractures. MethodsBetween June 2011 and December 2013, 22 patients with thoracolumbar burst fractures were included. There were 14 males and 8 females, aged 20-60 years (mean, 42.5 years). The fracture segments included T11 in 1 case, T12 in 4 cases, L1 in 10 cases, L2 in 6 cases, and L3 in 1 case. According to AO classification system, there were 13 cases of type A and 9 cases of type B. Spinal cord injury was classified as grade C in 2 cases, grade D in 3 cases, and grade E in 17 cases according to Frankel scale. The time from injury to operation was 3-10 days (mean, 5.5 days). All patients underwent posterior reduction and fixation via the injured vertebra, transpedicular balloon reduction of the endplate and calcium sulfate cement (CSC) injection. The ratio of anterior vertebral height, the ratio of central vertebral height, the sagittal Cobb angle, the restoration of nervous function, and internal fixation failure were analyzed. ResultsPrimary healing of incision was obtained in the others except 2 cases of poor healing, which was cured after dressing change or debridement. All the patients were followed up 9-40 months (mean, 15 months). CSC leakage occurred in 2 cases. Absorption of CSC was observed at 8 weeks after operation with complete absorption time of 12-16 weeks (mean, 13.2 weeks). The mean fracture healing time was 18.5 weeks (range, 16-20 weeks). The ratio of anterior vertebral height, ratio of central vertebral height, and sagittal Cobb angle were significantly improved at 1 week and 3 months after operation and last follow-up when compared with preoperative values (P<0.01), but no significant difference was found among 3 time points after operation (P>0.01). There was no internal fixation failure or Cobb angle loss more than 10°. Frankel scale was improved with no deterioration of neurologic function injury. ConclusionBalloon vertebroplasty combined with short-segment pedicle screw instrumentation is simple and safe for the treatment of thoracolumbar burst fractures, and it can improve the quality of reduction, restore vertebral mechanical performance effectively, and prevent the loss of correction and internal fixation failure.
ObjectiveTo explore the value of the long time lower abdominal aorta balloon block technology in the pelvis or sacrum tumor surgery. MethodsFrom January 2005 to June 2013, the sacrum or pelvic tumor patients underwent the long time lower abdominal aorta balloon block technology in the Orthopedics Department of West China Hospital of Sichuan University were enrolled. According to the balloon blocking time, patients were divided into A (<90 mins), B (90 to 180 mins), and C (>180 mins) groups. The intraoperative blood loss, blood transfusion amount, average lengths of hospital stay, postoperative volume of drainage, and postoperative complications were compared among the three groups. ResultsA total of 78 patients were included, of which 21 were in group A, 38 were in group B and 19 were in group C. All patients received en bloc resection, and did not experience intraoperative balloon shift and abdominal aorta flow leakage. Comparing the three groups, there were significant differences in intraoperative blood loss (P=0.026) and average lengths of hospital stay (P=0.021). Further pairwise comparison showed the intraoperative blood loss and average lengths of hospital stay in group C were significantly higher than those in group A and group B. In addition, there were no statistical differences among the three groups in blood transfusion amount, postoperative volume of drainage and postoperative complications. ConclusionIn the pelvis and sacrum tumor surgery, extending the time of abdominal aorta balloon block can reduce bleeding, save blood, increase the safety of surgery without increasing in postoperative complications.