Getting enough volume in autologous breast reconstruction can be difficult and transferring
multiple free flaps to reconstruct a single breast can provide a solution to that
problem. How to connect the free flaps pedicles to the recipient site has been a point
of discussion in the literature and two main approaches have been described. The first
one involves using the caudal stumps of the internal mammary (IM) vessels and is usually
referred to “cranial–caudal” approach. The second one implies the anastomosis between
one flap's pedicle to a branch of the other one.[1] This technique has been named in different ways in the literature: intraflap, flow-through,
daisy-chain, chain-link, and others.
In the present letter, we want to list what we think are all the advantages of the
intraflap approach compared with the cranial–caudal one. To our knowledge, some of
them have not been mentioned in the available literature.
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In the intraflap technique, the anastomoses of the first flap can be performed to
a perforator of the IM vessels (when sizeable) or to the IM vessels through a rib-sparing
approach ([Figs. 1] and [2]). Since the second flap is anastomosed to the first, there is no need for a wide
exposure of the IM vessels as required in the cranial–caudal technique. Reducing the
damage to the intercostal musculature and ribs lowers the postoperative pain and risk
of parasternal hollowing. The pedicles of the flaps mostly used for autologous breast
reconstruction (e.g., deep inferior epigastic artery perforator and profunda artery
perforator) usually offer some sizeable branches that can be used for the intraflap
technique and the branch with the most appropriate length and best caliber match to
the second flap's pedicle can be chosen. However, the caliber discrepancy or small
caliber of the available branches for the anastomoses can pose a technical challenge
to the less experienced surgeons.
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The intraflap anastomosis of the second flap to the first can be performed in a more
comfortable, more “external” position for the surgeon ([Figs. 1] and [2]) compared with the cranial–caudal technique where the microsuturing is performed
in a deeper and more limited space. Alternatively, the intraflap anastomoses between
the two flaps can be performed on a side table before transferring the construct (technically
a prefabricated chimeric flap) to the chest and performing the anastomosis to the
IM vessels.
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If the first flap (the one anastomosed to the IM vessels) is completely deepithelialized
and buried, just the second “external” flap needs to be monitored. In fact, a good
perfusion of the second flap implies patent anastomoses of the buried one. This is
shown in [Fig. 3] (the patient signed informed consent to publish her photo). In the cranial–caudal
anastomosis, if one flap is completely deepithelialized and buried, the postoperative
monitoring is not possible or requires special monitoring devices (e.g., flow coupler).
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The quality of IM vessels in previously irradiated patient can be poor and the anastomosis
can be challenging. Using the intraflap technique reduces the number of anastomoses
to the damaged IM vessels. Moreover, if the IM vessels are unusable for any reason,
the intraflap technique allows a double flap reconstruction using another recipient
pedicle (such as the subscapular system where a cranio–caudal approach is not possible/has
never been described).
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The IM vein will often bifurcate at the third to fourth intercostal space, thus rendering
the caudal venous anastomosis more challenging. The overall reliability of the retrograde
IM vessels has been questioned by several authors.[2]
[3]
Fig. 1 A case of bilateral autologous breast reconstruction using stacked flaps. The PAP
flap is anastomosed to the IM vessel using a rib-sparing approach and the SIEA flap
is anastomosed to a branch of the PAP flap. The first flap (PAP) can be completely
deepithelialized and buried to give volume and projection. The second flap (SIEA)
will reconstruct the missing lower pole and serve to monitor the perfusion postoperatively.
A functioning second flap implies functioning anastomoses of the first flap. IM, internal
mammary; PAP, profunda artery perforator; SIEA, superficial inferior epigastric artery.
Fig. 2 Closeup picture of the intraflap anastomoses of the SIEA pedicle to the PAP pedicle.
Two veins and one artery are shown on the green background. Note how the intraflap
anastomoses can be performed on the chest wall in a more comfortable, more external
position if compared with the anastomoses to the IM vessels that are situated deeper
in a narrower space. IM, internal mammary; PAP, profunda artery perforator; SIEA,
superficial inferior epigastric artery.
Fig. 3 Final intraoperative picture. The external flaps are used to reconstruct the lower
pole and serve for postoperative monitoring.
It must be mentioned that in the intraflap technique, an anastomotic failure of the
first flap at the IM vessels would put at risk both flaps, thus constituting a disadvantage
over the cranial–caudal technique.
Another advantage of the cranial–caudal approach is the surgeon's convenience of having
a single vascular axis (the IM artery and vein) as recipient for both flaps pedicles'
anastomoses. The preparation of the vessels and the microsurgical suturing can be
performed under the microscope in a single microsurgical field without changing the
microscope and surgeon's position. [Fig. 4] helps visualize some of the listed advantages and disadvantages of the two techniques.
Fig. 4 Schematic representation of the two techniques.
Having taken all these considerations into account we favor the intraflap technique
and do not perform the cranio–caudal approach anymore.
