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Published on: October 9, 2017
In vitro expansion patterns of ameroid ring constrictors
Steven S Leshem1, Peter J Lotsikas, S Brent Reimer
1Iowa State University Veterinary Teaching Hospital, Ames, IA 50011, USA.
American Journal of Veterinary Research
|November 5, 2008
Summary
The outer stainless steel ring on ameroid ring constrictors (ARCs) may not be essential for closing portosystemic shunts. ARCs without the outer ring showed significant expansion, while those with it did not.
Area of Science:
- Veterinary Surgery
- Medical Devices
- Vascular Surgery
Background:
- Ameroid ring constrictors (ARCs) are used to attenuate portosystemic shunts.
- The role of the outer stainless steel ring in ARC function is not fully understood.
Purpose of the Study:
- To evaluate and quantify in vitro dimensional changes of ARCs with and without their outer stainless steel ring over 34 days.
Main Methods:
- 12 ARCs (5.0-mm diameter) were tested in canine plasma.
- Six ARCs (group N) lacked the outer ring, and six (group R) retained it.
- Dimensional changes (inner/outer diameter, luminal area, height) were measured over 34 days.
Main Results:
- Group R constructs showed no significant change in inner diameter or luminal area.
- Group N constructs exhibited significant increases in inner diameter, outer diameter, luminal area, and height.
- Significant differences in dimensional changes were observed between groups over 34 days.
Conclusions:
- ARCs without the outer ring demonstrated significant centrifugal expansion.
- ARCs with the outer ring showed insignificant centripetal swelling without closure.
- The outer stainless steel ring may not be necessary for attenuating and closing some portosystemic shunts.
