【Abstract】Objective To evaluate the clinical value of photoplethysmography (PPG) in the diagnosis of venous valvular incompetence of lower extremity. Methods Two hundreds and six lower limbs in 181 patients including primary deep venous incompetence(PDVI), simple superficial veins incompetence and simple cross veins incompetence were examined by PPG in the assessment of venous refill time(VRT). All limbs underwent deep vein venography. Results Using venography as control the sensitivity of PPG was 89.8% and the specificity was 83.3 % in the diagnosis of venous valvular incompetence of lower extremity. Conclusion PPG could be taken as clinical diagnostic method for venous valvular incompetence of the lower extremity. The feature of PPG is noninvasive, painless with nonallergic reaction. The authors suggest that PPG can be used as a screening procedure for performing venography and postoperative follow-up.
Objective To compare canine decel luarized venous valve stent combining endothel ial progenitor cells (EPC) with native venous valve in terms of venous valve closure mechanism in normal physiological conditions. Methods Thirty-six male hybrid dogs weighing 15-18 kg were used. The left femoral vein with valve from 12 dogs was harvested to prepare decelluarized valved venous stent combined with EPC. The rest 24 dogs were randomly divided into the experimental group and the control group (n=12 per group). In the experimental group, EPC obtained from the bone marrowthrough in vitro ampl ification were cultured, the cells at passage 3 (5 × 106 cells/mL) were seeded on the stent, and the general and HE staining observations were performed before and after the seeding of the cells. In the experimental group, allogenic decelluarized valved venous stent combined with EPC was transplanted to the left femoral vein region, while in the control group, the autogenous vein venous valve was implanted in situ. Color Doppler Ultrasound exam was performed 4 weeks after transplantation to compare the direction and velocity of blood flow in the distal and proximal end of the valve, and the changes of vein diameter in the valve sinus before and after the closure of venous valve when the dogs changed from supine position to reverse trendelenburg position. Results General and HE staining observations before and after cell seeding: the decelluarized valved venous stent maintained its fiber and collagen structure, and the EPC were planted on the decelluarized stent successfully through bioreactor. During the period from the reverse trendelenburg position to the starting point for the closure of the valve, the reverse flow of blood occurred in the experimental group with the velocity of (1.4 ± 0.3) cm/s; while in the control group, there was no reverse flow of blood, but the peak flow rate was decreased from (21.3 ± 2.1) cm/s to (18.2 ± 3.3) cm/s. In the control group, the active period of valve, the starting point for the closure of the valve, and the time between the beginning of closure and the complete closure was (918 ± 46), (712 ± 48), and (154 ± 29) ms, respectively; while in the experimental group, it was (989 ± 53), (785 ± 43), and (223 ± 29) ms, respectively. There was significant difference between two groups (P lt; 0.05).After the complete closure of valve, no reverse flow of blood occurred in two groups. The vein diameter in the valve sinus of the experimental and the control group after the valve closure was increased by 116.8% ± 2.0% and 118.5% ± 2.2%, respectively, when compared with the value before valve closure (P gt; 0.05). Conclusion Canine decelluarized venous valve stent combined with EPC is remarkably different from natural venous valve in terms of the valve closure mechanism in physiological condition. The former rel ies on the reverse flow of blood and the latter is related to the decreased velocity of blood flow and the increased pressure of vein in the venous sinus segment.
Objective To investigate the value of color Doppler ultrasonography in the examination of perforating veins of the lower extremities by comparing with X-ray antegrade venography. Methods Fifty-three patients (60 lower extremities) clinically diagnosed with varicosis of the great saphenous vein from January 2014 to March 2016 were selected for color Doppler ultrasonography and X-ray antegrade venography. The results were compared and confirmed by surgery. Results Forty-seven lower extremities were diagnosed with perforating venous valve insufficiency by color Doppler ultrasonography, while 50 lower extremities by X-ray antegrade venography. There was no significant difference between the two methods (χ2=0.800, P=0.371). A total of 78 perforating veins were detected by color Doppler ultrasonography, with 1–4 perforating veins per one lower extremity. Among them, 66 perforating veins had an internal diameter of 2–5 mm, accounting for 84.6%. Except two perforating veins with an internal diameter <2 mm, the rest showed reflux. In addition, a total of 73 perforating veins presented distance to the pelma of 10–32 mm (foot-boot), accounting for 93.6%. Fifty-two lower extremities with varicosis of the great saphenous vein underwent laser ablation of the great saphenous vein with high ligation or + devascularization of perforating veins. Compared with operation findings, color Doppler ultrasonography in diagnosis of perforating venous valve insufficiency had 37 true positives, 2 false positives, 10 true negatives and 3 false negatives, and the sensitivity was 92.5% (37/40), the specificity was 83.3% (10/12), the accuracy rate was 90.4% (47/52). Conclusions Color Doppler ultrasonography can accurately localize perforating veins, measure the internal diameter and observe the degree of reflux. It is of high sensitivity and accuracy in the diagnosis of perforating venous valve insufficiency. Moreover, it is safe, simple and economical, and suitable for preoperative and intraoperative diagnosis and localization.