Description
The operation is performed under general anesthetic, often supplemented by a
paravertebral block. Adequate preoperative planning and preparation is key to the
success of latissimus dorsi (LD) breast reconstruction. Good lighting, careful positioning,
and high-quality equipment simplify the procedure. Appropriate intravenous
antibiotics are given for 24 h. An island of skin and underlying latissimus
dorsi muscle is raised from the back attached to its thoracodorsal vascular pedicle
and tunneled anteriorly to reach the ipsilateral chest. Immediate LD breast reconstruction
(IBR) is carried out at the same time as mastectomy.
It avoids the need
to recreate the breast pocket and re-dissect the axilla, which comprise the initial
steps of delayed LD breast reconstruction (DBR). Outcomes are closely related
to the accuracy of the preoperative markup. This should include the position and
size of the breast pocket, the exact extent of the fl ap harvest, and the position of the
anterior skin incisions and the posterior skin island. The markup should always be
performed prior to surgery and never in the operating theater. The use of templates
helps in the selection of the most appropriate expander or implant and defi nes the
exact limits of the breast pocket. The patient should be preloaded with intravenous
crystalloid solution to maximize fl ap perfusion.
Anatomical Points
Variations in the anatomy of the chest wall and axilla are encountered only occasionally
during breast reconstruction and include Poland’s syndrome (hyperplasia
of the breast, pectoralis muscle, and chest wall) and an additional head to LD, which
passes anterior to the axillary vein. Variations in vascular anatomy are more common.
The subscapular trunk normally lies deeply in the lateral aspect of the axilla,
as it approaches the tendinous part of LD. It gives off one or two branches to serratus
anterior, before continuing as the thoracodorsal artery. Two variations can give
rise to intraoperative confusion and may lead to inadvertent damage. First, the trunk
may lie more medially in the axilla. In this situation, the subscapular vein may
be mistaken for one of the lateral thoracic veins. The subscapular vein drains into
the posterior wall of the axillary vein, but the lateral thoracic veins drain into the
inferior wall of the axillary vein and are intimately related to the intercostobrachial
nerves. This relationship should be confi rmed before dividing them, in order to
avoid inadvertent division of the subscapular vein near its origin. Secondly, a lateral
thoracic vein occasionally drains into the subscapular vein rather than directly into
the axillary vein. Failure to recognize this variation may again lead to ligation and
division of the subscapular vein, which is mistaken for the proximal segment of a
lateral thoracic vein. Two further anatomical variations may be encountered when
performing DBR in a patient with a previously dissected axilla. First, the thoracodorsal
trunk may be plastered to serratus anterior by scar tissue on the medial wall
of the axilla. Careful identifi cation and dissection are vital to avoid confusion and
inadvertent damage to the trunk. This is made easier by identifying the vessels low
down in the axilla as they enter LD and dissecting them free from surrounding scar
tissue, working in a cranial direction. Second, the subscapular trunk may have been
divided during a previous radical axillary dissection. This leads to a reversal of the
blood fl ow in the serratus anterior branches through a rich network of anastomoses
with the intercostal vessels. Providing the serratus anterior branches are patent and
reversed pulsatile fl ow can be demonstrated, it should be possible to elevate the LD
fl ap on this alternative blood supply.
Perspective
Serious complications following LD reconstruction which require
immediate intervention are rare. They include total or partial fl ap loss, major
hemorrhage, and fulminating primary infection. Careful dissection, hemostasis,
appropriate antibiotic cover, and adequate experience should help to reduce the
incidence of these events to well under 1 %. It is much more common to encounter
less major complications, either early in the postoperative period or later. The most
frequent early problems include malposition of the fl ap, the skin island, or the prosthesis.
These can be avoided by careful planning, fl ap design, and a well-stocked
implant bank. Asymmetry is another early common problem which can be minimized
by the use of tissue expanders, allowing adjustment of the size and shape of
the breast. Prolonged drainage of serous fl uid and recurrent donor site seroma formation
are very common sequelae to this type of surgery, rather than complications.
The most common late complications include those relating to implants (see section
on implants), the fl ap, and the donor site. The risk of a malpositioned implant
is greater after DBR, and the risk of capsule formation is greater after radiotherapy.
A number of late problems may be encountered with the fl ap. These include an axillary
“bulge,” which can be prevented by high division of the tendon. This allows the
fl ap to drop down out of the axilla into the breast pocket and helps to create a more
ptotic breast. Spontaneous, unsightly and sometimes painful contraction of the flap
may be prevented by prophylactic division of the thoracodorsal nerve or treated
by secondary division of the nerve in the few patients who are affected. Failure to
suture the perimeter of the fl ap all around the resection defect can result in incomplete
muscle cover, leading to physical wrinkling and creasing of the implant where
it lies immediately under the skin.
Up to 30 % of patients experience some loss of shoulder mobility and
strength, affecting adduction, extension, and external rotation of the arm. Donor
site seroma formation may be reduced by using “quilting” sutures to obliterate
the donor cavity. A few patients develop chronic seromas which may require
treatment by excision of the cavity wall and insertion of a secondary drain.
Chronic donor site pain is uncommon and diffi cult to treat and may respond to a
paravertebral block.
Major complications: Major complications can be divided into those which
require early intervention and those which present later and are debilitating enough
to affect quality of life.
Early Complications
Total or partial fl ap loss is a rare disaster which can be avoided by understanding
axillary anatomy, its anomalies, and the pitfalls associated with previous axillary
dissection. A necrotic fl ap should be excised as soon as the diagnosis has been
confi rmed. Skin envelope necrosis is becoming more common with the advent of
skin- sparing mastectomy. It may be treated by excision and primary suture or excision
and grafting, depending on the extent of skin loss.
Signifi cant hemorrhage into the donor site or around the prosthesis requires early
exploration. It is common to fi nd several bleeding points which require control.
Conservative treatment by continuing with closed drainage delays recovery and
increases the risks of late capsule formation.
A clear-cut postoperative peri-prosthetic infection settles down rapidly after
removal of the implant, which can be replaced some 4–6 months later. Displacement
of the implant into the axilla or even into the donor site requires prompt replacement
and re-suturing of the lateral wall of the implant pocket, in order to prevent
recurrence.
Debilitating Late Complications
Adverse capsular contracture (ACC) is a progressive condition occurring in up to
20 % of patients within 10 year of implantation. It leads to pain, distortion, and
asymmetry and may be reduced by meticulous hemostasis and an aseptic technique.
Implant-based breast reconstruction should be avoided when radiotherapy is
planned in view of the very high risk of ACC in patients undergoing radiotherapy
after implant-based breast reconstruction. ACC, poor wound closure, and overambitious
tissue expansion may lead to implant extrusion. The underlying cause should
be corrected before attempting reinsertion.
A number of factors may lead to progressive asymmetry, including the use of a
prosthesis of inappropriate size, poor positioning, progressive contralateral ptosis,
and ACC. Asymmetry occurs in up to 50 % of reconstructed patients. It requires
correction when it affects quality of life, either by contralateral augmentation or
reduction or by ipsilateral revisional surgery. Symmastia is an extreme form of
asymmetry resulting from loss of the cleavage. It is almost impossible to correct.
Finally, the rate of local recurrence in the reconstructed breast is less than 1 %
per annum. Recurrences deep to the prosthesis are extremely rare and treatment
will depend on presentation. “Spot” recurrences in nonirradiated reconstructions
may be managed by local excision and radiotherapy, providing clear margins can be
achieved. “Field” recurrences will require additional systemic therapy.
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