WIDTH OF THE GREAT SAPHENOUS VEIN LUMEN IN THE GROIN AND OCCURENCE OF SIGNIFICANT REFLUX IN THE SAPHENO-FEMORAL JUNCTION

Foam-in-Vein: Characterisation of Blood Displacement Efficacy of Liquid Sclerosing Foams

Sclerotherapy is among the least invasive and most commonly utilised treatment options for varicose veins. Nonetheless, it does not cure varicosities permanently and recurrence rates are of up to 64%. Although sclerosing foams have been extensively characterised with respect to their bench-top properties, such as bubble size distribution and half-life, little is known about their flow behaviour within the venous environment during treatment. Additionally, current methods of foam characterisation do not recapitulate the end-point administration conditions, hindering optimisation of therapeutic efficacy. Here, a therapeutically relevant apparatus has been used to obtain a clinically relevant rheological model of sclerosing foams. This model was then correlated with a therapeutically applicable parameter-i.e., the capability of foams to displace blood within a vein. A pipe viscometry apparatus was employed to obtain a rheological model of 1% polidocanol foams across shear rates of 6 s^-1 to 400 s^-1. Two different foam formulation techniques (double syringe system and Tessari) and three liquid-to-gas ratios (1:3, 1:4 and 1:5) were investigated. A power-law model was employed on the rheological data to obtain the apparent viscosity of foams. In a separate experiment, a finite volume of foam was injected into a PTFE tube to displace a blood surrogate solution (0.2% w/v carboxymethyl cellulose). The displaced blood surrogate was collected, weighed, and correlated with foam's apparent viscosity. Results showed a decreasing displacement efficacy with foam dryness and injection flowrate. Furthermore, an asymptotic model was formulated that may be used to predict the extent of blood displacement for a given foam formulation and volume. The developed model could guide clinicians in their selection of a foam formulation that exhibits the greatest blood displacement efficacy.

Foam-in-vein: A review of rheological properties and characterization methods for optimization of sclerosing foams

Varicose veins are chronic venous defects that affect >20% of the population in developed countries. Among potential treatments, sclerotherapy is one of the most commonly used. It involves endovenous injection of a surfactant solution (or foam) in varicose veins, inducing damage to the endothelial layer and subsequent vessel sclerosis. Treatments have proven to be effective in the short-term, however recurrence is reported at rates of up to 64% 5-year post-treatment. Thus, once diagnosed with varicosities there is a high probability of a permanently reduced quality of life. Recently, foam sclerotherapy has become increasingly popular over its liquid counterpart, since foams can treat larger and longer varicosities more effectively, they can be imaged using ultrasound, and require lower amounts of sclerosing agent. In order to minimize recurrence rates however, an investigation of current treatment methods should lead to more effective and long-lasting effects. The literature is populated with studies aimed at characterizing the fundamental physics of aqueous foams; nevertheless, there is a significant need for appropriate product development platforms. Despite successfully capturing the microstructural evolution of aqueous foams, the complexity of current models renders them inadequate for pharmaceutical development. This review article will focus on the physics of foams and the attempts at optimizing them for sclerotherapy. This takes the form of a discussion of the most recent numerical and experimental models, as well as an overview of clinically relevant parameters. This holistic approach could contribute to better foam characterization methods that patients may eventually derive long term benefit from.

The effect of commercial insurance policies on outcomes of venous ablation

OBJECTIVE

The use of venous ablation (VA) for treatment of chronic venous insufficiency has exponentially increased. To limit cost and overuse, insurance companies have adopted aleatory policies. The goal of this study was to compare the policies of five major local insurance carriers and to determine whether treatment within the criteria of a certain policy is associated with improved patient outcomes.

METHODS

A retrospective single-center review of patients treated with VA was performed. Demographics, comorbidities, symptoms, and clinical class (Clinical, Etiology, Anatomy, and Pathophysiology classification) were recorded. Clinical success was defined on chart review by the patients' reporting of improvement or resolution of symptoms in the leg treated on follow-up, and technical success was defined by vein closure on ultrasound. Patients underwent a telephone survey inquiring about intensity of symptoms on a numeric rating scale of 0 to 10 before and after treatment of each leg as well as effects on quality of life (QOL). The policies of Aetna, Cigna, Anthem Blue Cross Blue Shield, UnitedHealthcare, and Connecticut Care were reviewed. The clinical and technical success rates were compared when veins were treated within the criteria of each policy. A subgroup analysis looking at patients who had clinical success only was performed to determine the potential rate of denial of coverage for each policy. A multivariable analysis was performed to determine independent predictors of clinical success.

RESULTS

There were 253 patients with 341 legs treated. The mean age was 58.5 ± 15.2 years (68% women). The most common symptom was pain (89.7%), with 47.8% of patients having C3 disease. The clinical success, technical success, and complication rates were 84.2%, 95.1%, and 5.6%, respectively. On survey, there was improvement of the numeric rating scale score in 84.3% of legs treated after the procedure, and 76.7% continued to experience improvement after a mean follow-up of 26.8 months. There was improvement of QOL in 76.5% of patients. There was no significant difference in procedural success, technical success, complication rate, or improvement in QOL when patients were treated within any of the five insurance policies. On multivariable analysis, there was no single policy significantly associated with clinical success. However, subgroup analysis of procedures with clinical success (n = 287) showed a significant difference between the five policies on analysis of the potential denial of coverage, ranging from 5.6% for Connecticut Care to 64.1% for UnitedHealthcare (P < .0001).

CONCLUSIONS

The different insurance policies have no correlation with outcomes of VA. Policies with more stringent criteria typically restrict treatment to larger veins and deny procedures to a significant number of patients with chronic venous insufficiency who can benefit from them.

Endovenous laser ablation in patients with wide diameter of the proximal segment of the great saphenous vein: Comparison of methods

Objective

To estimate the safety and efficacy of using the laser 1560 nm wavelength for treatment of chronic venous disease in patients with wide diameters of the proximal segment of the great saphenous vein.

Methods

In the study 88 patients with lower limb varicose veins were included. Maximum diameter of the great saphenous vein proximal segment varied from 15 to 34 mm (22 ± 2.3) in all patients. In the 1st group in 34 cases crossektomy and endovenous laser ablation (EVLA) were performed. In the 2nd group in 30 cases EVLA regardless diameter of the great saphenous vein proximal segment was performed. In the 3rd group in 34 cases EVLA taking into account the diameter of the great saphenous vein proximal segment was performed. The laser 1560 nm wavelength was used. Linear endovenous energy density in the 1st and 2nd groups was 90 J/cm for the proximal segment and trunk of great saphenous vein. Linear endovenous energy density in the 3rd group was personalized on the size of the veins: 100 J/cm for diameter of great saphenous vein proximal segment 15–20 mm, 150 J/cm for diameter 20–30 mm, 90 J/cm for middle and distal segments of great saphenous vein.

Results

In the 1st group obliteration of the trunk of the great saphenous veins and accessory great saphenous veins in all cases without additional interventions was reached. In the 2nd group at four cases (13.3%) the second procedure EVLA was carried out, after which the obliteration of the trunk was achieved. In the 3rd group the obliteration of the trunk of great saphenous vein was achieved without additional interventions.

Conclusion

Our experience of using the laser 1560 nm wavelength for the treatment of the chronic venous disease in patients with wide diameter of the proximal segment of great saphenous vein shows the safety and efficacy of this technique. EVLA has to be personalized on the size of the segments of vein in patients with wide proximal segment of great saphenous vein.