Perforator Phase Contrast Angiography of Deep Inferior Epigastric Perforators: A Better Preoperative Imaging Tool for Flap Surgery than Computed Tomographic Angiography?
Yang X, Miller MJ, Friel HT, Slijepcevic A, Knopp MV
Invest Radiol 52 334-342 06/01/2017
OBJECTIVE: The aim of this study was to demonstrate the feasibility of in vivo perforator visualization by a newly proposed magnetic resonance-based perforator phase contrast angiography (pPCA) technique for deep inferior epigastric perforator (DIEP) flap surgery and to prospectively compare its image quality and clinical value with computed tomographic angiography (CTA), the state-of-the-art perforator imaging technique.
MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. DIEP pPCA and CTA data were acquired in 10 female patients before DIEP flap surgery. Image findings were compared between the two techniques and with literature reports.
RESULTS: The overall image quality is negatively correlated with patient BMI for CTA, but positively correlated with BMI for pPCA. Compared with CTA, pPCA has significantly better image quality (P = 0.005), signal-to-noise ratio (P < 0.001), and contrast-to-noise ratio (perforator-to-muscle, P < 0.001; perforator-to-fat, P = 0.014). It also has preferable clinical value ratings, although not statistically significant (P = 0.388). There is a good agreement (84%) between perforators detected by pPCA and CTA. Perforator location deviations between pPCA and CTA are compatible with the precision required for plastic surgery. Perforator size measured by pPCA seems to be more accurate than CTA, as it is 0.8 ± 0.3 mm smaller (P < 0.001), consistent with the reported 0.5 to 1.2 mm overestimation by CTA. There is no significant difference in perforator intramuscular course assessment (P = 0.415).
CONCLUSIONS: The developed magnetic resonance-based pPCA technique presents superior image quality, better vessel contrast, and more accurate perforator anatomy than the x-ray-based CTA. pPCA has the potential to emerge as the preferred preoperative planning tool for perforator flap reconstructive surgery.