How to Assess Sensory Recovery After Breast Reconstruction Surgery?

BACKGROUND: We evaluated clinical against psychophysical (tactile and thermal quantitative sensory test [QST]), neurophysiologic (somatosensory evoked potential [SEP]), and epithelial nerve fiber density (ENFD) examinations in detection and follow-up of sensory alterations after breast reconstruction done with or without nerve anastomoses.

PATIENTS AND METHODS: In a prospective 2-year follow-up design, 56 breast cancer patients underwent innervated and 20 patients noninnervated free rectus abdominis muscle-sparing flap (ms-TRAM) breast reconstruction. Healthy contralateral breasts (36 patients) and 20 healthy volunteer women served as control participants. The diagnostic values of clinical examination, QST, SEP, and ENFD tests were assessed at baseline, and 1 and 2 years postoperatively.

RESULTS: Sensation of mastectomized thoracic skin was impaired before reconstruction surgery, confirmed with QST (P < .001 for tactile, warm and cool detection; others not significant). All tests were further impaired at 1 year (P < .012-.0001), but mostly showed improvement during subsequent follow-up (P < .001-.0001), except for vibration and 2-point discrimination, ENFD, and SEP. QST improved diagnostic accuracy for large as well as small fiber function performing best in assessing sensory recovery at 2 years. Of clinical tests, sharp-blunt discrimination was modestly useful (sensitivity, 0.85; poor specificity, 0.17). Two-point and vibration discrimination tests had poor diagnostic values. SEP recording was modestly sensitive (0.50), but not specific (0.25). Because of sparse epithelial innervation already at baseline, ENFD performed poorly.

CONCLUSION: Most tests could identify sensory nerve damage postoperatively. Tactile and thermal QST were most reliable, and sensitive also in confirming sensory recovery. SEP recording was useful especially in differentiating surgical techniques, whereas ENFD and clinical examination performed poorly, with the exception of sharp-blunt discrimination.