Subclavian Venography

• Arm swelling
• Pre-pacemaker placement
• Pre-op for dialysis fistula
• Poorly functioning dialysis fistua

Patient Preparation: start intravenous line in the arm on the same side as the subclavian vein that is to be imaged. Connect SmartSet intrvenous tubing (www.topspins.com, 734-623-6400). If both left and right subclavian veins are to be imaged or if imaging the SVC is essential, than start bilateral intravenous lines. The intravenous site should be located preferably in the antecubital fossa. Intravenous sites in the forearm, wrist or hand are also acceptable provided they can tolerate a flow rate of 2ml/sec. Any size angiocatheter down to 22 gauge is acceptable. Smaller angiocatheters (larger gauge number) may have too much resistance to allow a sufficient rate of contrast injection.

After starting the intravenous lines, place cushions under both forearms and elbows to raise up the arms so they will be included in the relatively anterior imaging volume required to encompass the subclavian veins.

Dilution of Gadolinium: Mix one bottle of gadolinium (10 or 20 ml) into a 250ml bag of normal saline. It is acceptable to use sterile water or D5W or D5 1/2NS in patients who are salt restricted. This is especially important in patients with a history of congestive heart failure. Fill four, 60ml syringes with the diluted gadolinium contrast and attach two loaded syringes to each SmartSet.

Patient Position: Feet first, supine,

Landmark: mid sternum or mid-nipple line. Landmark lower if you need to cover more of the arm veins.

Coil: If imaging just one arm, use the torso array coil positioned over the shoulder on the side of interest and extend medial enough to cover the SVC.If bilateral, use the body coil.

SERIES 1: Sagittal T1 spin echo localizer.

Adjust the field-of-view so as the cover at least up to the level of the thyroid. The necessary size field-of-view can be determined by measuring from the landmark site up to the thyroid cartilage. In thin patients some time can be saved by using ¾ field of view.

SERIES 2: Coronal 3D MR Venography with injection of dilute gadolinium

This sequence produces a venogram image which is comparable to venography performed using X-rays and iodinated contrast. It has the advantage of using gadolinium which is completely safe and can be diluted 10 to 20-fold so that a large volume of dilute Gd will distend the venous system and demonstrate venous anatomy over a large field of view.

• Additional Parameters
• Collapse
• Set field-of-view equal to width of patient at the shoulders
• Multiphase = at least 3 but pause after each acquisition so you can allow the patient to catch the breath
• Do not use "Smartprep" or "centric" ordering of k-space, sequential ordering of k-space produces less artifact.
• Sequence of Events:
• Attach two syringes (both filled with 60ml dilute Gd) to the iv in each arm (a total of four, 60ml syringes filled with dilute Gd). Test each iv by advancing 7ml of dilute Gd to fill the coiled tubing.
• Pre-contrast scan: "Start" the first acquisition without any injection of contrast (this can be used as a mask image for substraction).. Check images to be sure the position is correct and the wrap-around artifact is not excessive. Check the positioning by identifying the SVC and subclavian veins.
• Hyperventillation: Before starting injection of dilute Gd, hyperventillate the patient (deep breath in, deep breath out, deep breath in……). Watch the patient’s chest rise and fall to confirm the patient is paying attention and following the breathing instructions.

• Start Injecting: After 2 deep breaths, begin injecting the dilute Gd into both arms. Injection rate should be at least 2 ml/sec. Continue hyperventillating the patient. Do not start the scan yet.
• Gd-enhanced Scan: Once the first 60ml syringes are emptied, continue immediately with the second 60ml syringes at the same injection rate and with no delay. Once the second syringes have begun, "START" the scan with the patient suspending breathing in full inspiration.
• Once the scan finishes, have the patient take 2 quick breaths and suspend breathing again for a 3^rd scan.
• If for any reasons the scan did not turn out well, REPEAT it with injection of additional dilute Gd.

Filming: Use windows workstation to obtain subvolume MIPs of upper extremity veins in AP and oblique projections.

Billing:    MRA Chest 771555
                Computer Recontructions 76375

ICD9 codes

• Thrombosis: 451.8
• Subclavian vein: 451.89
• Axillary vein: 451.89
• Brachial vein: 451.83
• Basilic vein: 451.82
• Vena cava: 453.2
• Unspecified: 459.9

Sample Normal Dictation:

The patient was imaged with a Sagittal T1 weighted sequence and a Coronal 3D spoiled gradient echo pulse sequence during infusion of dilute gadolinium. Following acquisition of image data further analysis was performed on a computer workstation to obtain reformations and MIPs of the major vessels.
The axillary, subclavian and brachiocephalic veins and SVC are widely patent. No significant narrowing or thrombus is identified.
Impression:
Normal SVC and axillary, subclavian and brachiocephalic veins bilaterally.