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PART 4 — PERIPHERAL VENOUS
objectives evaluated. There are general, overall health questionnaires such as the SF-36. The Aberdeen questionnaire examines detailed peripheral venous performance. The CIVIC-2 is an example of a sim- plified peripheral venous performance questionnaire and has been used successfully in the evaluation of radio-frequency treatment.
SONOGRAPHIC EXAMINATION TECHNIQUES
Duplex Doppler ultrasonography (US) has become the standard technology to evaluate CVVI. Several objectives are accomplished with US of the periph- eral venous system and can include:
• Screening
• Definitive diagnosis
• Pretreatment mapping
• Peritreatment mapping, guidance, and comple-
tion ultrasonography
• Posttreatment follow-up
• Patient follow-up
The US examination for CVVI has two major di-
agnostic goals. The first is to rule out deep venous obstruction or even acute venous thrombosis. The second is the evaluation of valvular insufficiency or reflux detection.
Screening is a concise evaluation of patients at risk or with a high probability of having CVVI. It could be the basis for prevalence studies.
A definitive diagnosis includes an evaluation of the deep veins and a segmental evaluation of re- flux in the main veins. Differential diagnosis of a nonvenous disease such as types of edema (e.g., lymphedema), arterial pathology (e.g., popliteal an- eurysm), masses (e.g., hematoma), among others are part of definitive diagnosis.
Pretreatment “mapping,” a term typically associ- ated with determination of superficial venous loca- tion, registers details of reflux sources and drainage, perforating vein competence, and vein diameters as a secondary variable.26,27 Details of the report are often influenced by the technical thoroughness of perioperative US. Some reports should include de- tailed measurements to localize source, drainage, or perforating veins’ precise location. Availability of perioperative US minimizes the need for such de- tails. One single examination serves as screening, definitive diagnosis, and perioperative mapping in many centers.
Peritreatment US varies on the type of treatment planned. Using ultrasound guidance, some centers place skin markings with a pen or marker along the course of the vein, which creates a pretreatment “mapping.” US guidance has become a standard for
thermal and chemical ablation treatment. Comple- tion ultrasonography documents patency of the deep venous system and efficacy of superficial venous ablation or eradication.
Follow-up examinations can be subdivided into two categories: (1) direct assessment of individual veins and (2) assessment of overall pathophysiolog- ic condition. US is used for the direct assessment of individual veins postprocedure. Air plethysmogra- phy determines overall effects caused by pathology in virtually all veins draining the lower extremity. Photoplethysmography, in its most common, sim- plest form, gives a compound representation of the effects of venous reflux in the region tested. These specific techniques are described later in this chapter. US has become the most popular, most used, and most mandatory examination to evaluate CVVI. Air plethysmography, however, is likely a better indicator of treatment performance, providing a global assessment of total limb venous function.
Although invasive, venography or phlebography is another diagnostic method to detect venous throm- bosis, congenital venous malformations, or valvular function. The venogram (another term is phlebog- raphy) is an x-ray of the veins after dye is injected distally (ascending) or by direct puncture of the con- trast into the common femoral vein or external iliac vein with the patient in a semierect position (de- scending). Less invasive methods are preferred by patients and ultrasonography has virtually replaced venography of the lower extremity.
TREATMENT TYPES
It is important for the sonographer to understand the various treatments for CVVI, as the use of ultra- sound varies with the treatment option. Treatment options for superficial venous disease include strip- ping, ligation, thermal ablation, chemical ablation/ sclerotherapy, and phlebectomy (microincision). Treatment for deep venous disease may include anticoagulation, valve replacement, venoplasty/ stenting, and thrombolysis or chemical/physical recanalization.
Stripping and ligation of the superficial veins have been traditional treatments for decades. Ligation alone has been associated with “neo- vascularization.” This side effect perhaps may be better described as neodilatation of small arter- ies and veins due to injury, fresh thrombosis, and inflammation.
Endovenous thermal ablation by radio-frequency or laser energy has become a popular choice for the treatment of saphenous and nonsaphenous trunk veins.28–30 Thermal ablation has largely replaced