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Page 4 of 9 Black et al. Plast Aesthet Res 2023;10:31 https://dx.doi.org/10.20517/2347-9264.2023.04

to result in necrosis more than radial horizontal, vertical and IMF incisions [5,15,27] . Carlson et al. reported an
odds ratio of 9.69 (P = 0.014) when studying nipple necrosis after periareolar incision compared to all other
incision types. After mastectomy, the branches of the internal mammary and lateral thoracic vessels that
normally perfuse the NAC are disrupted; periareolar incisions further damage the subdermal plexus
supplying the NAC, resulting in skin necrosis that particularly impacts this region. Our institution, like
many others, preferentially uses IMF incisions when possible due to the reduced rates of skin necrosis,
improved surgical access to the breast pocket, and aesthetic benefits of concealing the scar below the lower
pole of the breast.

Reconstructive options
Patients deciding to pursue either implant-based or autologous reconstruction must consider oncologic
treatment regimens, patient comorbidities, aesthetics, and recovery time, among other factors. Though skin
necrosis is not the only outcome of interest, it is highly influenced by this choice; Sue et al. demonstrated a
threefold difference in necrosis rates between autologous flaps and implants (30.4% in flaps, and 10.6% in
implants), and Lee et al. found a higher rate of necrosis in free flaps compared to pedicled flaps, with an
odds ratio of 1.575 [18,28] . This increased risk is attributed to the acute stress placed on the breast skin during
the microvascular reconstruction, compared to the often-employed two-stage alloplastic technique of slowly
inflating tissue expanders (TE) before transitioning to permanent implants. Supporting this theory, higher
initial TE fill volumes have been shown to predispose patients to skin necrosis [10,20] . A study by Sue et al.
found that initial TE volumes greater than 200 mL were associated with an 11.4% risk of necrosis, compared
to 5.4% in TEs filled less than 200 mL initially (P = 0.02) .
[10]

Our own study of 902 breasts across 530 patients found a significant difference between breast skin necrosis
rates after immediate reconstruction with either DIEP flaps (373 breasts, 26.8% necrosis) or tissue expanders
(529 breasts, 15.5% necrosis). However, after controlling for BMI and patient comorbidities, this difference
[19]
became insignificant . As our DIEP cohort had a significantly higher BMI, mastectomy specimen weight,
and prevalence of diabetes, it is possible that these factors, rather than the procedure itself, may be to blame
for increased rates of skin necrosis. Higher-BMI patients are better suited for autologous reconstruction
than low-BMI patients given the need for sufficient donor tissue, leading to a selection bias that would be
difficult to study in a controlled setting. Nevertheless, skin necrosis following autologous reconstruction is
easier managed by banking skin during the index operation than in an alloplastic setting which may require
a more aesthetically deforming surgery due to the risk of device extrusion and infection [8,28] . The timing of
reconstruction can also impact the likelihood of skin necrosis. Though studies have shown that delayed
alloplastic reconstruction is associated with reduced rates of necrosis , this method subjects all patients to
[10]
an additional procedure, rather than just those who develop necrosis. These patients differ from those who
undergo two-stage DIEP flap reconstruction with skin banking (discussed below) because the additional
intermediate operation to place tissue expanders offers no new opportunity to improve cosmesis, as this can
be done during the placement of a permanent implant.

We routinely perform delayed DIEP flaps with intermediate, or “babysitter”, tissue expanders for patients
undergoing post-mastectomy radiation therapy, so as to avoid irradiating the healthy flap. In our study of
344 immediate DIEP flaps and 99 delayed flaps, we found lower rates of skin necrosis in the delayed group
compared to the immediate group (2.0% vs. 16.0%) . There were no differences in other measured
[29]
postoperative outcomes. Ultimately, we did not use these findings as an argument to perform delayed DIEP
flaps on all patients, as the skin banking technique has provided adequate reconstruction without an
additional procedure .
[13]