Relative importance of iliac vein obstruction in patients with post-thrombotic femoral vein occlusion.

Background: Patients with femoral vein occlusion rapidly develop collateral flow through the deep femoral vein, an embryonic collateral. In contrast, iliac vein collateralization is sparser and functionally poorer. It is not uncommon to have femoral vein occlusions associated with iliac vein obstruction, even though the femoral vein occlusion is often more readily apparent on venograms and duplex scans, whereas the iliac vein obstruction may remain occult.

Effect of External Positive and Negative Pressure on Venous Flow in an Experimental Model.

Objective: Positive external pressure is said to decrease transmural pressure; negative pressure in the pleural cavity is widely believed to result in negative pressure in systemic chest veins. The discrepancy between erect column height and foot venous pressure has been explained on this basis.

Methods: These core concepts rest on static closed models that may not be appropriate.

Treatment of iliac-caval outflow obstruction.

The importance of the obstructive component in chronic venous disease (CVD) with ulceration has been emphasized recently for a venous condition that has primarily focused on the reflux component. Modern imaging techniques, particularly intravascular ultrasound, have shown the frequency of the obstructive element in both post-thrombotic and nonthrombotic disease. The emergence of iliac vein stent angioplasty and its good results in the treatment of large vein and other diverse CVD subsets has strengthened the role of obstruction.

Utility of iliac vein stenting in elderly population older than 80 years.

Background: The geriatric population aged 80 years and older with severe manifestations of chronic venous disease face diminishing therapeutic options. Self-applied compression is often not possible because of frailty or arthritis. Significant limb swelling diminishes mobility, affects independent living, and precipitates institutionalization.

Quantifying saphenous reflux.

Background: Quantification of reflux is desirable in advanced chronic venous disease as clinical features are based on its adverse impact on ambulatory venous pressure (AMVP). Prior clinical observation suggests that reflux in a saphenous vein > 5 mm is likely significant. On the basis of normal calf pump mechanics, we hypothesized that a reflux volume ≥ 30 mL was necessary to upset pump equilibrium.

Anomalous features of iliac vein stenosis that affect diagnosis and treatment.

Background: Endovenous management of venous lesions is largely derived from arterial experience. However, venous lesions, particularly iliac vein stenoses, differ from their arterial counterparts in some crucial respects. Awareness of these differences is necessary for proper diagnosis and treatment.

Assessment of residual thrombus after venous thrombolytic regimens.

Background: We noticed substantial residual thrombus on intravascular ultrasound (IVUS) in many limbs despite restoration of flow after thrombolysis. Since thrombus burden has been tied to post-thrombotic syndrome (PTS), the frequency and extent of residual thrombus after thrombolysis is important. We present such an analysis below.

A modification of iliac vein stent technique.

Background: Iliac vein stenting has emerged as a promising new technology to address a wide spectrum of advanced chronic venous disease. Wallstent™ has been the commonest stent type used in reported experience. It has excellent long-term patency with good clinical outcome, but is prone to compression/migration of the upper end of the stent requiring reinterventions.

Hemodynamics of "critical" venous stenosis and stent treatment.

Background: The concept of "critical" stenosis at which there is a sharp reduction in forward flow is derived from arterial disease. The critical element in venous stenoses is upstream pressure, not downstream flow. Many venous symptoms and microvascular injury are related to venous hypertension.

Endovenous management of venous leg ulcers.

Background: Compression is the current "standard" in the treatment of venous leg ulcers, and corrective surgery is ancillary. The emergence of safe and effective minimally invasive corrective techniques prompts a reappraisal of this paradigm.

Methods: Among 192 consecutive limbs with venous leg ulcers, 189 were treated by (1) endovenous laser ablation (n = 30), (2) iliac vein stent placement (n = 89), or (3) both (n = 69).

Best management options for chronic iliac vein stenosis and occlusion.

Background: Iliac vein stenting technology is rapidly emerging as a minimally invasive alternative to traditional open venovenous bypass procedures for iliac vein stenoses and chronic total occlusions.

Methods: Peer-reviewed publications meeting eligibility criteria were retrieved and reviewed from public domain databases.

Results: Reviewed reports encompass ∼1500 patients.

[Wounds in vascular and metabolic diseases].

There are many causes of leg ulcer development; however, vascular etiology is most commonly involved. Venous or lymphatic causes underlay 80% and arterial or arteriovenous causes 20%-25% of cases. Over years, the prevalence of arteriovenous ulcers has increased due to the increased prevalence of peripheral arterial disease.

[Wounds and dermatoses].

Wounds are a hallmark of various skin diseases. Most patients with wounds suffer from chronic venous insufficiency or other vascular diseases. Autoimmune, infective, metabolic, malignant, some psychiatric and diseases caused by environmental factors like radiation, present with skin and mucosal erosions and ulcerations.

Postural and ambulatory changes in regional flow and skin perfusion.

Background: Studies of orthostatic changes in cutaneous micro-perfusion have yielded conflicting results, likely from imprecision of legacy equipment.

Methods: Postural flow changes in the femoral vessels and cervical carotids were measured in healthy normal adults using duplex equipment. Nutrient skin flow was measured using Hyperspectral imager (OxyVu-2™), a newer non-touch measurement technology.

Diagnosis and treatment of venous lymphedema.

Background: Chronic venous disease (CVD) is a common cause of secondary lymphedema. Venous lymphedema is sometimes misdiagnosed as primary lymphedema and does not receive optimal treatment. We have routinely used intravascular ultrasound (IVUS) imaging in all cases of limb swelling.

Iliac vein stenting in postmenopausal leg swelling.

Background: Leg swelling in menopausal women is well known. Prevailing concept in primary care is that it is polycentric and a treatable cause may not be found. Patients are placed on empiric diuretics often without benefit.

Hand-assisted laparoscopic nephrectomy for renal cell cancer with renal vein tumor thrombus.

Objectives: To assess outcomes after hand-assisted laparoscopic nephrectomy (HALN) for renal cell cancer tumor thrombus confined to the renal vein and to compare outcomes with published series in this setting.

Methods: Thirteen patients underwent HALN for radiologic T3b disease (tumor thrombus confined to the renal vein on preoperative computed tomography) under the care of three surgeons at two centers between 1997 and 2006.

Results: Median patient age was 69 years.