Abstract: Objective To investigate the role of combined interventional procedures in the treatment of old deep vein thrombosis. METHODS: The clinical data of a total of 12 limbs of 12 patients with old deep vein thrombosis from January 2006 to September 2006 were retrospectively analyzed. The duration of the disease was 4 months-3 years, and the thrombus was stripped from the femoral vein incision, and a guidewire and catheter were fed through the gap between the thrombus break and the vein wall at the stripping site, and the thrombus was bluntly separated from the vein wall gap to the inferior vena cava, and the entire proximal deep vein was dilated with a balloon, and the main trunk was clear on imaging, followed by stripping or reconstruction of the thrombus at the entrance of the saphenous vein confluence. The distal end of the incision was dilated in the same way and the volume of incoming blood was ensured to be satisfactory. A vascular patch was formed and the femoral vein incision was enlarged. RESULTS: All 12 patients were opened, and all of them were treated with high elastic stockings and drug-assisted therapy after surgery. Conclusion: Interventional combined surgery is a new method for the treatment of old deep vein thrombosis. Many patients with lower extremity deep vein thrombosis (DVT) gradually evolve into old thrombosis due to lack of timely treatment or incomplete catheter thrombolysis, and the formation of old thrombosis is often accompanied by venous reflux obstruction and impaired valve function, which significantly reduces the quality of life of patients. From January 2006 to September 2006, the authors treated 12 cases of post thrombosis syndrome (PTS) using a combination of intra- and extra-cavitary surgery and achieved satisfactory results. The results are reported as follows. Clinical data The 12 patients with PTS in this group, 9 were male and 3 were female. The age was 32-74 years. The lesions involved the left lower extremity in 8 cases and the right lower extremity in 4 cases. The onset of the disease was 3 months-2 years in 11 patients and 3 years in 1 patient. 12 patients mainly presented with swelling and weakness of the affected limb, which was significantly aggravated after walking. Severe cases were accompanied by skin ulcers in the foot and shoe area. All patients in this group underwent deep vein ultrasound and deep vein cascade and catheter retrograde contrast angiography before surgery. The external iliac vein and femoral vein were completely occluded in 11 cases, and the femoral vein alone was occluded in one case. All cases involved the confluence of the saphenous vein. 12 patients showed a patent inferior vena cava and none of them underwent inferior vena cava filter placement. The diagnosis was clear in the whole group of cases. Surgical method: The surgery was performed under DSA. The inguinal incision was used to expose the deep femoral vein, and the vein was explored after incision. In 11 patients, the cast thrombus was removed from the incision site, and a 0.35 loach guidewire was fed through the gap between the thrombus break and the vein wall in a prograde direction, and the thrombus was bluntly separated from the vein wall gap to the inferior vena cava with a guidewire under DSA, followed by a single curved or black loach catheter with a super rigid guidewire, and a full proximal deep vein balloon was performed. Dilatation is performed, and the distal end of the incision is stripped of the thrombus as much as possible, and balloon dilation of the distal end is also performed under DSA. Until the blood flow was satisfactory. In one 3-year-old patient with PTS, the deep vein at the confluence of the saphenous vein was almost completely occluded at the inguinal incision, which was about 4 cm long. In 12 patients, the amount of blood coming from the proximal and distal ends of the incision was satisfactory. The thrombotic end of the incision was fixed to the anterior wall of the vein and then the femoral vein incision was shaped with an artificial vascular patch. All patients showed that the blood flow was restored. Postoperatively, all patients were treated with anticoagulation and thrombolytic therapy and high elastic stockings. Surgical efficacy and follow-up: All 12 patients showed significant improvement in clinical symptoms from 3-7 d after surgery. The average follow-up period was 4 months, and all of them took anticoagulation and antiplatelet drugs on time and according to the dose. The follow-up period was confirmed by ultrasound, and none of the 12 patients had restenosis or secondary thrombosis. Discussion: Conservative treatment of post-deep vein thrombosis syndrome is often not very effective, and the traditional surgical treatment is usually suprapubic saphenous vein diversion, which is a limited option for patients with PTS: (1) the lesion is limited to the blocked iliac vein of one limb; (2) the distal superficial femoral vein is basically patent; (3) the iliofemoral vein on the healthy side including the inferior vena cava is patent; (4) the saphenous vein on the healthy side is patent and the internal diameter of the saphenous vein is greater than 4 mm. The procedure is also related to the operator’s surgical operation and technique, and the second reason is that the saphenous vein has low drainage and is easily compressed by external forces, which may lead to secondary thrombosis. The current development of combined intra- and extravascular techniques provides new ideas and methods for patients with PTS. In the author’s opinion, for patients with PTS with a complete main stem occlusion and a clear diagnosis, surgical exploration can be performed directly under DSA by stripping the incisional thrombus and then entering the mudskipper guidewire under DSA surveillance and exchanging the superrigid guidewire for a balloon dilation and shaping through the catheter. The same approach was taken at the distal end of the incision. The author believes that late long-segment old thrombus can be shaped by balloon dilation between the thrombus and the vein wall because of the weak elasticity of the thrombus and the compensatory expansion of the vein wall, and to keep the blood flowing smoothly and certain perfusion pressure after the angioplasty. Patients are advised to get out of bed early with the assistance of high-elastic stockings or elastic bandages to maintain intravenous flow pressure. Continuous postoperative medication and physical therapy can achieve significant results. Because of the good compliance and support of the soft tip of the mudskipper guidewire, it is relatively safe and successful to use the mudskipper guidewire under DSA to bluntly separate the gap between the vein wall and the thrombus in patients with long occlusions. In patients with limited stenosis of the iliac vein and significant retraction after ball expansion, stenting of the stenosis should be performed in a timely manner and the catheter should be placed retrogradely into the distal part of the stenosis by puncturing from the healthy side, with continuous postoperative administration of thrombolytic drugs via the catheter to prevent secondary thrombosis after retrieval. The duration of catheterization is usually 3-5 d. If necessary, the duration of catheterization can be extended. In conclusion, for the treatment of post-deep vein thrombosis syndrome, the venous stenosis and the site of obstruction should be clarified first, and the author believes that surgical treatment is not necessary for old thrombosis below the femoral N vein. In my opinion, no surgical treatment is needed for old thrombosis below the N femoral vein. Therefore, the symptoms can be relieved with appropriate medication and conservative treatment with high elastic stockings. For patients with trunk occlusion and involvement of the saphenous vein opening, a combined intra- and extra-cavitary surgery is needed to open the trunk vessels to restore venous return to the lower extremity, and patients with involvement of the saphenous vein confluence need to undergo saphenous vein reconstruction. In this group of cases, this method was adopted to achieve more satisfactory results. The author believes that the range of indications for surgical or interventional treatment of PTS alone is relatively small, and both procedures have their limitations. The combination of the two techniques can be effectively integrated in the therapeutic approach and each has its own advantages. Therefore, combined intra- and extra-cavitary surgery provides a new approach and idea for the treatment of PTS patients.