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Updated: Mar 9, 2026

Computed Tomography (CT) Guided Implantation of a Totally Implantable Venous Access Port (TIVAP) through Subclavian Vein
Published on: January 13, 2026
Comparison of Inversion ("flipping") Rates Among Different Port Designs: A Single-Center Experience
Vahid Etezadi1,2, Scott O Trerotola3
1Division of Interventional Radiology, Department of Radiology, University of Pennsylvania Medical Center, 1 Silverstein, 3400 Spruce Street, Philadelphia, PA, 19104, USA.
Purpose:
To compare incidence of port inversion among different types of implantable venous access devices.
Materials And Methods:
Records of patients who underwent imaging-guided subcutaneous port placement without port fixation between July 2001 and April 2015 were reviewed with use of a quality assurance database. 1930 patients with complete follow-up (death or explant) were included in the study. Collected data included date and indication for port placement, port type, venous access site, immediate and long-term complications, indication for removal, and total number of catheter days. BMI of patients with inverted ports was also calculated.
Results:
Port inversion within the pocket was observed in 18 patients (0.9%) including 7/82 (9%) of Dignity ports, 4/126 (3%) of Vaxcel plastic arm ports, 3/142 (2%) of Smartports, 2/100 (2%) of Powerports, 1/14 (7%) of Vaccess ports, and 1/1421 (0.07%) of Vortex LP ports. Among these designs, the inversion rate was significantly lower in Vortex LP ports (0.1%) (P < 0.05). There was a trend toward higher inversion rate of Dignity ports, which have a rectangular design with a relatively narrow base. Mean dwell in inverted ports was 114 days (7-580).
Conclusion:
The incidence of port inversion without suture fixation of the port base to the pocket is extremely low. The present study shows differences in inversion incidence based on port design.
Level Of Evidence:
Case Series, Level IV.
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