IS Case 153: Fibrin sheath

Charles Hubeny, MD

Imaging Sciences URMC 2008
Publication Date: 2009-05-21


Patient is a 58-year-old female, with a history of breast cancer receiving chemotherapy, presenting with a port that will flush but unable to withdraw blood.


Findings consistent with fibrin sheath formation along the distal catheter tip.


Fibrin sheath


Fibrin sheath formation along with malpositioning, catheter migration, vessel stenosis, and venous thrombosis is a common non-infectious complication of long-term central venous catheters. Fibrin sheaths are thought to form from endothelial injury either at the site of vessel entry or distally from the catheter tip injuring the vessel wall. Proteinaceous material may start forming on the catheter in less than 24 hours and can extend along the entire length in as early as 5-7 days after placement. Fluid infusion is still possible but a fibrin sheath usually prevents the withdraw of blood due to a negative pressure valve mechanism.

Catheter venography is the best method of detecting a fibrin sheath. The study is easily performed by injecting 5-20 mL of contrast in the catheter while filming rapidly. A fibrin sheath can cause a variable appearance and most reliable sign is the lack of a straight jet of contrast through the line. A common appearance shows a thin reflux of contrast that travels up between the catheter and the fibrin sheath before spilling into the vein. Best images are obtained earlier in the study as further in the study the catheter tip may be obscured by contrast filling the vein. Rarely contrast may reflux up the entire length of the catheter and out the entry site into the soft tissues or on the skin. In the absence of a fibrin sheath, a straight jet of contrast should be seen spilling out the tip into the venous system.

Once a fibrin sheath is detected a central line can be exchanged over wire or removed and replaced in a different location. If venous access is difficult then other techniques can be used to salvage the catheter such as fibrinolysis (using agents such as streptokinase or tPA), transfemoral mechanical fibrin stripping with a snare, or internal snare maneuvers. Regarding patiency, central line replacement is more superior to other methods.


  1. Cassidy FP Jr, Zajko AB, Bron KM, Reilly JJ Jr, Peitzman AB, Steed DL. Noninfectious complications of long-term central venous catheters: radiologic evaluation and management. AJR Am J Roentgenol. 1987 Oct;149(4):671-5. [PMID: 3498313]
  2. Crain MR, Horton MG, Mewissen MW. Fibrin sheaths complicating central venous catheters. AJR Am J Roentgenol. 1998 Aug;171(2):341-6. [PMID: 9694448]
  3. Reddy AS, Lang EV, Cutts J, Loh S, Rosen MP. Fibrin sheath removal from central venous catheters: an internal snare manoeuvre. Nephrol Dial Transplant. 2007 Jun;22(6):1762-5. [PMID: 17403697]

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