Immune Profiles in Multiple Sclerosis (MS) Patients and Healthy Volunteers Through Thoracic Duct Cannulation

"Contrast is injected into lymph nodes until lymphatics visualized at about level of L3 lumbar spine. After target lymphatic vessel is identified, needle is passed transabdominally into the vessel. Guidewire is advanced through the needle into the lymph vessel \& advanced into thoracic duct. Microcatheter is then advanced into thoracic duct over the wire.~IN \& OUT-up to 100mL collected via catheter over 30-min at 2 levels within thoracic duct, then catheter removed.~INDWELLING-As described above, then guidewire placed through original catheter \& advanced into subclavian vein. Vascular sheath is placed into vein in the upper arm under ultrasound/fluoroscopy guidance. Wire in the subclavian vein then snared through venous access sheath \& pulled out. Catheter then threaded \& advanced over the wire until tip is in thoracic duct. Catheter from thoracic duct removed, leaving catheter extending from arm into thoracic duct. Catheter left in place up to 21 days for sampling."