Long-Term Serial Measurement of Muscle Volume in TRAM Flaps Using the Eclipse Treatment Planning System

Area of Science:

• Plastic Surgery
• Radiology
• Biomedical Engineering

Background:

• Muscle flaps in reconstructive surgery are prone to volume loss due to denervation and disuse.
• Quantitative methods for assessing muscle volume changes in flaps are not standardized.
• Transverse rectus abdominis musculocutaneous (TRAM) flap breast reconstruction is a common procedure where volume changes are a concern.

Purpose of the Study:

• To conduct long-term serial measurements of muscle volume in TRAM flaps used for breast reconstruction.
• To establish a quantitative approach for evaluating muscle volume changes in TRAM flaps.
• To assess the rate and extent of volume loss in TRAM flaps over time.

Main Methods:

• Retrospective review of patients undergoing unilateral immediate breast reconstruction with pedicled TRAM flaps (2004-2007).
• Inclusion criteria: completion of three serial CT scans, no history of recurrence or radiation.
• Eclipse software used for 3D reconstruction and volume calculation of the rectus abdominis muscle; contralateral side served as control.

Main Results:

• 35 patients met inclusion criteria out of 451 TRAM flap surgeries.
• Mean rectus abdominis muscle volume ratios were 27.1% (15 mo), 22.1% (30 mo), and 19.8% (51 mo).
• Extrapolated final volume ratio converged at 19.4%; contralateral muscle volume remained stable.

Conclusions:

• TRAM flap muscle volume decreases significantly, losing over 70% in the first 15 months and stabilizing near 20% of original size.
• The Eclipse treatment planning system can be utilized for retrospective volume measurements.
• Findings provide a quantitative basis for understanding TRAM flap volume dynamics in breast reconstruction.