Venography/ Phlebography- Avinesh Shrestha

Venography is a radiological procedure for the evaluation of the veins by the help of intravenous radiological contrast media. It is also known as phlebography. Contrast venography is the gold standard for judging diagnostic imaging methods for deep venous thrombosis; although, because of its cost, invasiveness, the increased sensitivity of sonography to demonstrate pathology and other limitations this test is rarely performed.

1. VENOGRAPHY

2. OVERVIEW Angiography refers to radiologic imaging of blood vessels after injection of contrast media. Highly specialized imaging equipment is required for these procedures . Angiography can be more specifically described as follows: Arteriography Venography Angiocardiography

3. ANGIOGRAPHY TEAM Angiography is performed by a team of health professionals, including a radiologist (or other qualified angiographer), a “scrub/OR” nurse or technologist who assists with sterile and catheterization procedures, and a radiologic technologist. Depending on the departmental protocol and the specific situation, an additional physician, nurse, technologist, or hemodynamic technologist may be available to assist with the procedure.

4. Angiographic Requirements ANGIOGRAPHIC ROOM The procedure room should be specifically designed to accommodate the sophisticated and accessory equipment as well as angiographic team and other staffs. An angiographic room is equipped for all types of angiographic and interventional procedures and has a wide variety of needles, catheters, and guide wires close at hand. It is larger than conventional radiographic rooms and includes a sink and scrub area and a patient holding area. The room must have outlets for oxygen and suction as well as emergency medical equipment must be nearby .

5. Angiographic Imaging Equipment EQUIPMENT REQUIREMENTS A table that provides access to the patient from all sides ; it should have four-way floating capability, adjustable height , and a tilting mechanism. An fluoroscopy imaging system with intensifier or the newer flat detector digital fluoroscopy acquisition type ; both of these systems are available in C-arm. Electromechanical injector for delivery of contrast media. Physiologic monitoring equipment that allows monitoring of the patient’s venous and arterial pressures, oxygen levels, and electrocardiogram. Image archiving method linked to a PACS and laser printer

6. Angiographic Imaging Equipment Hemostats Preparation sponges & antiseptic solution Scalpel blade Syringe and needle for local anesthetic Basins and medicine cup Sterile drapes and towels Band-Aids(Fixing Tapes) Sterile image intensifier cover Needle(Butterfly, IV cannula) for vessel(vein) puncture, if catheterization is not done. ANGIOGRAPHIC TRAY A sterile tray contains the basic equipment necessary for a catheterization. Basic sterile items include the following:

7. Introduction Venography/phlebography is a procedure in which x-ray of the veins, is taken after a special dye is injected into the veins. The dye has to be injected constantly via a catheter, making it an invasive procedure. Contrast venography is the gold standard for judging diagnostic imaging methods for deep venous thrombosis; although, because of its cost, invasiveness, the increased sensitivity of sonography to demonstrate pathology and other limitations this test is rarely performed Venography can also be used to distinguish blood clots from obstructions in the veins, to evaluate congenital vein problems, to see how the deep leg vein valves are working, or to identify a vein for arterial bypass grafting.

8. Specific venographic procedures Venography can be divided into following sections: Peripheral Venography Lower limb venography Upper limb Venography Peripheral Varicography Central Venography Inferior Vena Cavography Superior Vena Cavography Selective visceral Venography Renal venography Hepatic Venography Portal venography

9. Patient preparation Some common procedure for patient preparation are: NPO for 4-6hrs prior to examination Check recent serum creatinine(M:60-130;F:40-110µmol/L) and urea(1.6-7µmol/L) level. Taking proper medical history so that appropriate premedication can be used. Changing patient to an appropriate gown. Signing Informed consent * These may not be discussed in the specific sections of venography as these are common points to all the venographic procedures.

10. Contraindications(Relative) Common Contraindications for venography include contrast media allergy, impaired renal function blood-clotting disorders Anticoagulant medication unstable cardiopulmonary or neurologic status . non-consent by patient to procedure * These may not be discussed in the specific sections of venography as these are common points to all the venographic procedures.

11. Peripheral venography It is the study of the veins of the extremities. It is still considered the gold standard for diagnosis of deep venous thrombosis, but is now only very rarely performed It can be studied under: Upper limb venography Lower limb venography Peripheral Varicography

12. Lower limb venography It is the study of the veins of the lower limb by the introduction of contrast medium.

13. ANATOMY: The veins of the lower limb can be divided into a superficial and a deep venous system. Superficial veins: Great saphenous vein Small saphenous vein and their tributaries( originates in the foot and extends posteriorly along the leg, terminating at the knee, where it empties into the popliteal vein. ) Superficial veins of the foot. Lower limb venography

14. ANATOMY: Deep veins: Posterior tibial Anterior tibial (The posterior tibial and anterior tibial veins joins distally with the dorsal venous arch to drain the foot and lower leg and join proximally to become the popliteal vein at the level of the knee . ) Popliteal ( The popliteal vein continues upward to become the femoral vein before becoming the external iliac vein) Femoral . Lower limb venography

15. Indication Deep vein thrombosis of lower limb To demonstrate incompetent perforating veins Suspected venous obstruction(by tumor or extrinsic pressure) Investigation of varicose ulcers in the post thrombotic syndrome Secondary or recurrent varicose veins Patient with swollen legs Outlining venous malformation Edema of unknown cause Congenital abnormality of the venous system.

16. contraindication Local sepsis Acute deep vein thrombosis Conventional/advanced Fluoroscopy unit with spot film device and tilting radiography table Butterfly needle Equipment

17. Contrast media Low/ Iso osmolar contrast media 240mgI/ml Volume about 50-150 ml Patient preparation Elevate the leg overnight if edema is severe.

18. procedure Patient is placed supine on the x-ray table with all elastic wrappings removed from the leg Preliminary radiograph of leg and thigh is taken in order to ascertain optimum exposure

19. Technique Ascending phlebography : Tourniquets applied just above the ankle and below the knee in order to occlude the superficial system and direct flow into the deep veins . Table tilted 65 degree from the horizontal feet down position in order to prevent layering of contrast medium Leg should be internally rotated in order to separate the tibia and fibula and the deep veins of the calf Weight should not be borne by the foot being injected so that the calf muscle remain relaxed and the vein can be filled with the contrast 23G butterfly needle is inserted into peripheral vein on the dorsum of the foot

20. Contd.. 40cc contrast medium is injected into the extremity either by hand or pressure injector First exposure is made about 2 minute after the beginning of injection focusing the legs If stereoscopic views are required , exposure of legs taken in second or stereo position 3 rd film is taken exposing the thigh The table is lowered again and another film is taken of the legs to determine the degree of stasis present Lastly , a separate exposure of the pelvis done by tilting the table back to the horizontal position as this position favors the filling of the pelvic veins with the contrast medium At the end of the procedure , needle should be flushed with 0.9% saline to avoid the risk of phlebitis

21. Contd.. Descending Phlebography: Less frequently done procedure Patient supine with feet against foot rest Femoral vein is puncture at the groin and with the needle insitu, patient is put in erect or near erect position and contrast injected If the patient performs valsalva maneuver contrast will reflux down an incompetent femoral vein into the popliteal vein

22. Images Anterior-posterior(AP)of calf. Both Oblique of calf(Internal and External) AP of popliteal, femoral and iliac veins. Aftercare The limb should be exercised.

23. Upper limb venography It is the study of the veins of the upper limb by the introduction of contrast medium.

24. Upper limb venography ANATOMY: The venous system of the upper limb may be divided into two sets: deep and superficial veins. Superficial veins: Cephalic vein Basilic vein Median cubital vein(it is anterior to the elbow joint ; the vein most commonly used to draw blood, which connects the superficial drainage systems of the forearm)

25. Upper limb venography ANATOMY: Deep veins: Brachial vein Radial vein Ulnar vein Palmer arch The deep brachial veins join the superficial basilic vein to form the axillary vein, which empties into the subclavian and finally into the superior vena cava.

26. Indication Oedema To demonstrate the site of venous obstruction SVC obstruction Congenital abnormality of the venous system Contrast medium Low/ Iso osmolar contrast medium of 300mgI/ml Equipment Conventional/advanced Fluoroscopy unit with spot film device and Tilting x-ray table

27. Technique The patient is supine An 18G butterfly needle is inserted into the median cubital vein at the elbow. The cephalic vein is not used, as this bypasses the axillary vein. Spot films are taken of the region of interest during a hand injection of 30 ml of contrast medium. Alternatively a digital subtraction angiographic run can be performed at 1 frame sec−1.

28. PERIPHERAL VARICOGRAPHY INDICATIONS To demonstrate distribution of varicose veins. To demonstrate sites of communication with deep venous system. Assessment of recurrent varicosity. Contraindications Local sepsis. CONTRAST MEDIUM LOCM/IOCM 240mgI/ml. Volume depends on extent and volume of varicosities.

29. TECHNIQUE The patient lies supine and tilted 40° head up to delay washout of contrast. A 19-G butterfly needle is inserted into a suitable varix below the knee. 40-50 ml of contrast are injected by hand under fluoroscopic control. A series of spot films is taken: AP calf and 2 obliques lateral knee - to assess the short sapheno -popliteal junction. If contrast filling above the knee is adequate, then further views of the thigh can be taken to demonstrate the extent of long saphenous varicosity. Due to the large volume of varicose veins, it may be necessary to re-site the needle in a suitable varix above the knee to obtain adequate contrast filling of the entire system. Contd..

30. Contd.. Contd.. A further 40 ml of contrast are then injected and spot films taken. AP thigh and oblique - particular attention should be given to the potential sites of communication, e.g. mid-thigh perforator AP and oblique of groin - views to demonstrate the sapheno -femoral junction arc particularly necessary in assessing recurrent varicosity even if there has been previous sapheno -femoral ligation, as recurrence at this site is common. After injection and imaging is complete the veins should be flushed with saline to prevent contrast stasis and the risk of phlebitis. The needles are removed and pressure applied to ensure hemostasis.

31. Aftercare The limb should be exercised gently to washout any remaining contrast

32. Central venography ANATOMY Veins of Thorax

33. Central venography ANATOMY Veins of Abdomen and pelvis

34. Inferior vena- cavography It is the Venography of the IVC It is performed primarily to rule out the existence of thrombus or the occlusion of the IVC The contrast medium is injected through a multiple side hole catheter inserted through the femoral vein and positioned in the common iliac vein or the inferior aspect of the IVC Radiographs may need to include the opacified vasculature from the catheter tip to the right atrium Representative injection and imaging programs are 20ml/sec for a 40 ml total volume of contrast medium and two image per second for 4-8 second in both planes Imaging begins at the end of suspended respiration

35. Indication To demonstrate the site of venous obstruction, displacement or infiltration As a preliminary examination in trans-venous interventional techniques To detect caval and renal anomalies To evaluate the status of the cava and its collaterals before ligation of the inferior vena cava Contraindications Active spreading thrombophlebitis Severe concurrent hepatic and renal dysfunction

36. Contrast media LOCM/IOCM 370mgI/ml, 40 ml Equipment Conventional/advanced fluoroscopy unit Catheter 5F with side holes Injector

37. Technique With the patient supine, the catheter is inserted into the femoral vein using the seldinger technique An injection of 40 ml of contrast medium is made in 2 seconds by the pump injector and recorded Better and more prolonged filling seen if patient perform valsalva maneuver

38. Films Rapid serial radiography is performed(Two film/frames per second for 5 seconds and one film per second for 5-10 second in AP and lateral positions) or as a digital subtraction run at 2 frames/s Aftercare Pressure at the venipuncture site Monitoring the patient

39. Superior vena- cavography Venography of the superior venacava is performed primarily to rule out the existence of thrombus or the occlusion of the superior venacava The contrast medium may be injected through a needle or an angiographic catheter introduced into a vein in an antecubital fossa , although superior opacification result from injection through the catheter positioned in the axillary or subclavian vein Radiographs should include the opacified subclavian vein, brachiocephalic vein, the SVC and the right atrium

40. Superior vena- cavography The injection program depends mostly on whether a needle , an angiographic catheter or a regular catheter is used A representative program for a catheter injection is 10 to 15 ml/sec for a 30 to 50 ml total volume of contrast medium Image are produced in both planes, if desired, at a rate of one or two image per second for 5-10 seconds and are made at the end of the suspended inspiration

41. Indication Thrombus or occlusion or stenosis of superior venacava To demonstrate the site of venous obstruction Congenital abnormality of the venous system e.g. left sided superior venacava As a preliminary examination in trans-venous interventional techniques

42. Technique The patient is supine PA view of upper chest and lower neck is taken as the preliminary film 18G butterfly needles are inserted into the medial antecubital vein of both arms Hand injection of contrast media 30 ml from each side, are made simultaneously, as rapidly as possible by two operators. The film sequence is started after two third of the contrast medium is injected.

43. Filming Aftercare Generally aftercare is not required unless the catheter is used Images are obtained at one frame/films per second for 10 second

44. SELECTIVE VISCERAL VENOGRAPHY The visceral veins are often visualized by extending the imaging program of the corresponding visceral artery injection. For example the veins that drain the small bowel are normally visualized by extending the imaging program of a superior mesenteric arteriogram.

45. RENAL VENOGRAPHY It is usually performed to rule out thrombosis of the renal vein . It is also catheterized for blood sampling , usually to measure the production of renin, an enzyme produced by kidney when it lacks adequate blood supply. The renal vein is most usually catheterized from a femoral vein approach. 16 ml volume of contrast is given at 8 ml/sec. 2 images per second are taken for 4 seconds.

46. HEPATIC VENOGRAPHY Performed to rule out stenosis or thrombus of the hepatic veins Also done to Obtain pressure measurements of the veins inside the liver Usually catheter enters jugular vein or upper limb veins but a femoral vein approach may also be used. Can be done by following method: The patient is placed in the supine position that include the liver tissue and the extreme upper inferior vena cava 30 ml volume of contrast is given at 10 ml/sec 1 image per second is taken for 8 seconds Exposures made at the end of suspended expiration .

47. PORTAL VENOGRAPHY To demonstrate prior to operation the anatomy of the portal system in patients with portal hypertension. To check the patency of a Porto-systemic anastomosis. LOCM 370, 50 ml is used. It can be performed by injecting the portal vein directly from a percutaneous approach but is usually accomplished by late phase imaging of splenic artery or a superior mesenteric arteriogram. Images are taken in Rapid serial radiography or digital subtraction runs: at one image s− 1 for 10 s.

48. Cerebral venography Cerebral veins are usually visualized during the procedure of cerebral angiography because the transit time from cerebral arteries two veins is very less(about 2-4 sec) Abnormalities at the base of the skull can be visualized by Jugular vein approach. Improper technique can results in a lack of intracranial Dural sinus filling which may disguise as venous occlusion. This problem is avoided by adequate neck compression along with proper volume and rate of delivery of contrast. I nternal carotid artery injection venous phase

49. CAPNOCAVOGRAPHY Visualization of inferior vena cava by injection of CO 2 into the vein It is ideal in patients who are allergic to iodinated contrast media and compromised renal function. The buoyancy of CO 2 makes it necessary for the procedure to be done in the left lateral position for optimal visualization of the IVC The main limitation of the technique is the possibility of neurotoxicity

50. Use of carbon dioxide (CO 2 ) as a contrast medium is demonstrated (appearing white along the right of the spine) on a frail 75 year old man.

51. RISKS AND COMPLICATIONS Angiographic, therefore venography procedures always involve some level of risk for the patient . Common risks and complications include the following : Due to technique: Bleeding at the puncture site Thrombus formation Embolus formation * These points may not be discussed in the specific sections of venography as these are common points to all the venographic procedures. Hematoma Dissection of a vessel Infection of puncture site Tissue necrosis due to extravasation

52. Contd.. Due to contrast media: Contrast media reaction Thrombophlebitis Cardiac arrhythmia * These points may not be discussed in the specific sections of venography as these are common points to all the venographic procedures.

53. RADIATION PROTECTION A potential risk exists for increased radiation dose to the members of the angiography team because of their proximity to the patient and equipment during the procedure. So, Careful use of radiation protection devices, such as lead aprons, thyroid shields, and lead glasses , is required. Ensuring that fluoroscopy time is absolutely minimized can also help in reducing dose. The use of pulsed fluoroscopy can also reduce radiation dose to the patient during angiography. Precise collimation is important for reducing the dose to the patient and the angiography team. Glass Lead shields may be suspended from the ceiling as an additional means of protecting the angiographer’s face and eyes.

54. Other modalities ULTRASOUND Ultrasound is the most widely used imaging method for the venous system The advantages are that it is low cost and readily available It is now the modality of choice because veins can be systematically examined using a combination of continuous wave, duplex and color Doppler systems ( demonstrates changes in the velocity of venous blood flow with 95% accuracy ) It can be used to assess the following : Lower limb veins Upper limb veins Abdominal veins including renal veins, hepatic and portal veins, and inferior vena cava Venous anatomy to assist in central venous line placement, e.g. for the internal jugular or subclavian vein.

55. Other modalities COMPUTED TOMOGRAPHY Multidetector CT (MDCT) with standard IV contrast and scan delay protocols for the chest or abdomen/pelvis is very effective for detection of compression or thrombosis of major veins including the superior and inferior vena cavae , iliac and renal veins. Although it would be possible to perform direct lower-limb CT venography after infusion of contrast via a foot vein, this technique has found little application and is not used in clinical practice .

56. Other modalities MAGNETIC RESONANCE IMAGING(MRI) MRI is well suited to imaging the venous system, but because of cost and limited availability it is used infrequently Peripheral MR venography ( MRV) is currently used in selected cases of: venous thrombosis in pregnant subjects and where fractured limbs are immobilized in casts. It is useful in evaluation of congenital abnormalities of peripheral venous anatomy and venous malformations . This is the best and most versatile imaging modality for the brain,

57. Conventional angiography You can see the bony skeleton Digital subtraction The bony skeleton is subtracted CT angiography MR angiography

58. CONCLUSION Conventional Venography is nearly 100% sensitive and specific in making the diagnosis of DVT. Accuracy is crucial since deep vein thrombosis can lead to pulmonary embolism, a condition that can be fatal. But, due to the development of newer modalities such as ultrasound, CT and MRI; these procedures are almost obsolete. Venography takes between 30-45 minutes .It is an invasive procedure requiring intravenous injection of contrast medium, and is painful and expensive. Failure to cannulate veins occurs with swollen limbs. False negative results do occur. It is especially useful when there is a strong suspicion of deep vein thrombosis, but non-invasive tests (ultrasound) have failed to identify the disease.

59. REFERENCES A guide to radiological procedure ;Stephen Chapman, 4 th and 6 th edition Clark’s special procedure in radiography Radiological procedures a guideline ; Dr. Bhushan N. Lakhkar . Merrill’s atlas of radiological procedures ; Vol3 Principle of anatomy and physiology ; Tortora and Derrickson T ext book of Radiographic anatomy and related anatomy; Kenneth L. Bontrager , MA John P. Lampignano , MEd, RT(R)(CT)

60. ??? What is Venography/Phlebography? Common Patient preparation? Indications of Lower limb venography? Images for Lower limb venography? Contraindications for venography? Risks and Complications?