Vascular check-up

Diagnostic procedure in the Phlebology

Lecture Dr. Natalia Brenner at the Medical Training

Clinical studies
Doppler sonography
LRR
Venous occlusion plethysmography
Duplex sonography

1.Diagnostische procedures in phlebology

Clinical Investigation
History: Family history, smoking habits, diabetes mellitus, hypertension, hyperlipidemia, varicose veins, DVT, thrombophlebitis, edema, subjective complaints, fractures, surgery.
Clinical Findings: Varikoseformen, Corona phleboectatica, edema, ulcers, pigmentation blanche, atrophy, induration.

Doppler sonography
The Doppler ultrasound examination is based on the Doppler effect: a sound wave is reflected from a moving object, then changes its frequency. In the investigation on the ultrasonic beam of the people moving corpuscular components of blood will be reflected and changed its frequency. The reflected ultrasound beams are recorded with the Doppler ultrasound devices graphically or acoustically. The frequency change is proportional to blood flow velocity.
For phlebological diagnostic equipment with 8-MHz and 4 – MHz probes and continuous sound emission used. Transmitter with a frequency of 8 MHz have a good resolution with only a small penetration depth of 3-4 cm. In deeper vessels or obese patients, a 4 – to fall back-MHz probe, which has a higher penetration depth.

Flow of the venous system diagnostics

This is based on the respiratory function of the flow signal and is carried out in the beds. The indications are of a suspected outflow obstacle (deep vein thrombosis or chronic deep vein closure).

Investigation points:

the femoral vein in the groin

the popliteal vein in the popliteal

the posterior tibial V.

the great saphenous vein (as collaterals)

When abdominal breathing is found in expiration a low flow signal to proximal, with the deep inspiration or when Valsavamanöver there is an increase in pressure in the abdomen, which exceeds the pressure in the venous system of the leg and thus leads to a distal valve closure and a stop of the flow signal – “S” sounds.

As an “A-Sound” – augmented the accelerated flow signals at the distal compression of the vein sounds-are named. For a proximally localized closure of the investigative body of the vein to the respiratory function of the flow signal is canceled. If the seal between the compression and Doppler probe position, so no A more sounds are triggered.

Reflux diagnosis of superficial and deep venous system
For the diagnosis of varicose veins and chronic venous insufficiency, the reflux diagnosis is of primary interest. This exploits that under physiological conditions in intact proximal flap conditions the venous blood after only distally and runs through the valve closure in patients with proximal pressure increase can not flow back to the distal end.

In contrast, insufficient valves may occur distal to a reflux of blood to flow against the normal direction. Valsavermanöver or by local compression and decompression, this pathological behavior will provoke reflux. As pathological reflux is one of at least 0.5 to 1 s in duration. With insufficient Krusty the vein can be traversed with the Doppler probe distally and repeated Valsalva or cough maneuvers as long as a reflux detected until the distal insufficiency point, the end of klappeninsuffizienten part is reached. In this way is a simple way the possible staging of varicosis Hach.
The diagnostics are based on the relaxed standing reflux patients.
Study sites of reflux in the superficial venous system diagnostics:

Krusty the great saphenous vein
Krusty the small saphenous vein

Perforant
Investigation points in the diagnosis of deep venous reflux system:

Femoral vein (groin)

Superficial femoral (thigh)

Popliteal (knee)

V. tibialis anterior (ventral side of the ankle)

Posterior tibial vein (medial retromalleolar)

LRR
The light-reflective Rheography (LRR) or photoplethysmography (PPG) has become established in practice for the routine screening and diagnosis.
Of a measuring head, the light in the near infrared range is radiated into the skin and reflected. The reflected component is registered and recorded by a scribe. The amount of reflected light depends on the filling of the cutaneous venous plexus. The measurement is made from a skin depth of about 0.3 to 2.3 mm. The method is temperature dependent. The room temperature during the measurement should be between 22 and 25 ° C..

The investigation is performed on a seated patient, with the lower leg is placed slightly forward. The measuring electrodes are glued about 10 cm above the medial malleolus to a healthy skin site.
The patient performs 10 maximum dorsiflexion of the foot within 15 seconds. During dorsiflexion occurs through the action of the ankle and calf muscle pump to empty the blood from the leg and to a reduction in intravenous pressure. Since the amount of reflected light depends on the filling of the veins of the skin, occurs during movement of the program to a measurable increase in the reflection. After completion of the program is moving the patient to sit quietly. In this phase, the cutaneous venous plexus fills slowly on the arterial leg again. The time this takes is called the recovery time (t0).
During a venous insufficiency occurs not only on the arterial limb but also retrograde venous insufficiency of the sections to a rapid filling of the venous plexus of the skin.

Depending on the venous recovery time and Blazek Wienert have three degrees of severity of venous dysfunction defined.

Grade 1: Venous recovery time t0 = 20-25
Grade 2: Venous recovery time t0 = 10-19 seconds seconds
Grade 3: Venous recovery time t 0 = less than 10 seconds

Tourniquet test
With a tourniquet is the superficial venous system compresses and repeated the same study program.
The tourniquet should be applied generally in the proximal lower leg. When suprafascial, tial improvement form of venous insufficiency will now extend the venous recovery time significantly and normalize.
This study is of particular importance and should always be performed at baseline pathology. Herewith a statement about the expected therapeutic effect on venous insufficiency with invasive therapeutic intervention is possible.
Causes of the Nichtbesserbarkeit Venous recovery time in LRR

Tial improvement 1.Non venous insufficiency. Reason: occlusion or valvular insufficiency of deep veins

Tial improvement not 2.Falsch venous insufficiency. Reason: not switched hemodynamically incompetent perforators

3.Vorgetäuschte venous insufficiency. Reason: conditional joint or muscular insufficiency of the pumping mechanisms

Tial improvement not 4.Scheinbar venous insufficiency. Reason: insufficient pressure of the tourniquet

Venous occlusion plethysmography

The plethysmographic measurement methods are volume-measuring tests, which is non-invasive way to obtain quantitative information about the venous and arterial function possible. Besides Wasserplethysmographie (Thulesius), Luftplethysmographie (Barbey, Nicolaides) the venous occlusion plethysmography with mercury strain gauge is known.

Measurement capabilities of venous occlusion plethysmography:

Venous capacity, venous outflow, venous refill time
Pump function
Resting blood flow
Reactive hyperemia
Pressure measurements

The investigation is performed in the supine position on a couch. The legs are directed at an angle of 45 degrees. Luftplethysmographie at an air-filled cuff is applied on the lower leg between the ankle and knee, which is connected to a pressure monitor and the computer. It identifies various parameters on which the venous filling index as a parameter for venous reflux and ejection fraction are important as a measure of the muscle pump function.

Duplex sonography
Duplex sonography combines the morphological information provided by the sonographic cross section with the functional data by the pulsed Doppler ultrasound. The Doppler signals are displayed next to the B-picture as flow information, it may contain statements about the diameter of the vessels and the flow rates are made. With color-coded Doppler devices, the directional information is color coded so that the vessels appear in different colors depending on the flow direction.

Indications:
Deep vein thrombosis
Superficial thrombophlebitis
Venous reflux examination in varicosis and postthrombotic.

Syndrome
The flow of studies and investigations of suspected thrombosis by lying out in the. Even in the U.S. imaging of intravascular thrombus due to increased intravascular structure and compressibility of the vessel under the repealed to diagnose. The information also shows the lack of Doppler flow in the thrombus. A complete thrombosis includes an assessment of the entire deep venous system, including the calf veins, the gastrocnemius and the soleal.
For the diagnosis of chronic venous insufficiency, duplex ultrasound is performed with the patient standing. The advantage over the conventional Doppler examination is that every vein, which is to be examined can be safely located.