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Source
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| Plastic
& Reconstructive Surgery
Volume: 98
Number: 4
Sept. 1996 |
|
The Internal Mammary Artery and Vein as a Recipient
Site for Free-Flap Breast Reconstruction: A Report of
110 Consecutive Cases
Charles L. Dupin, M.D., Robert J. Allen, M.D., Cynthia
A. Glass, M.D., and Ross Bunch, M.D.
New Orleans, La.
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Discussion
The most common recipient site for free-flap breast
reconstruction is the subscapular system. Because of
a number of problems we encountered using this recipient
site, we became interested in revisiting the internal
mammary vessels.
This paper reports the use of the internal mammary
artery and vein as a recipient site in 110 consecutive
cases of breast reconstruction in 87 patients. We also
report the technical details of recipient-vessel dissection
and vessel size in our series. Complications encountered
in the series are discussed, and the advantages of using
the internal mammary vessels are enumerated. Our experience
of a 99 percent successful flap transfer rate supports
the reliability of these recipient vessels in breast
reconstructions. (Plast. Reconstr. Surg. 98: 685,1996.)
The internal mammary vessels are attractive recipient
vessels for free-flap breast reconstruction. Shaw,1
in his original article describing the free gluteal
musculocutaneous flap for breast reconstruction, utilized
the vessels in the fifth intercostal space. He reported
that he could only use the internal mammary vein in
three of eight cases. He found that the internal mammary
vein was very small at the level of the fifth rib and
matched poorly with the large (and short) superior gluteal
vein, which averaged 3 mm in diameter. He later reported2
that in 75 percent of the cases he was able to use the
internal mammary vein, presumably by using a more proximal
rib level.
The development of the free transverse rectus abdominis
musculocutaneous (TRAM) flap with its longer pedicle
allowed the use of the subscapular system, and the internal
mammary system was largely abandoned. Feller3 in 1994
cautioned, "We do not recommend the use of the
internal mammary artery and vein as recipient vessels
owing to their unpredictable quality. Although the artery
might be adequate as a recipient vessel, the vein is
most often found to be inadequate as a recipient vein
so that the external jugular or the cephalic vein .
. . is pulled through subcutaneously into the dissected
chest pocket. This is time consuming and is disadvantaged
by the addition of scars on either the neck or the upper
arm."
Although we used the subscapular system as a recipient
site in our 44 free TRAM flaps and our first perforator
flaps, we noted the following problems:
- In secondary reconstructions (especially in radiated
cases), the dissection of axillary vessels was very
difficult.
- The thoracodorsal artery frequently was small (less
than 2 mm) and sometimes was found to have insufficient
flow, necessitating anastomosis to the circumflex
scapular artery more proximal in the subscapular system.
- Medial placement of the breast mound was restricted,
and lateral fullness of the flap was a common problem.
- Several patients sustained injury to the thoracodorsal
artery inadvertently during the axillary dissection,
rendering its use impossible.
- Two patients avulsed the arterial anastomosis with
shoulder motion (one was salvaged).
- Brachial plexus symptoms were seen (although transient),
and some patients developed a stiff shoulder resulting
from the restriction of shoulder action. These patients
required therapy and/or injection.
- Anastomosis in the axilla is technically difficult
for the assistant because he or she is operating across
the chest.
Development of the deep epigastric perforator flap4,5
and the superior gluteal artery flap6 7 encouraged us
to revisit the internal mammary vessels as a recipient
site. Between May of 1993 and February of 1995 we have
used these vessels exclusively in a series of 110 flaps.
We hoped to be able to solve some of the problems noted
above and to determine if the internal mammary vessels
were reliable recipient vessels for these perforator
flaps.
Patients and Methods
We performed 110 flaps on 87 patients. Most were reconstructions
following modified radical mastectomy, but a few were
implant replacement procedures. Seventy-four of the
flaps were deep epigastric perforator flaps, and 32
were superior gluteal artery flaps. Two inferior gluteal
artery flaps and two lateral thigh perforator flaps
completed the series. Eighty-seven of the flaps were
for immediate reconstruction, and 23 were for delayed
reconstruction. Ten patients had simultaneous bilateral
deep epigastric perforator flaps, 3 patients underwent
simultaneous bilateral superior gluteal artery flaps,
and 1 patient underwent bilateral simultaneous lateral
thigh perforator flaps for breast reconstruction.
Currently, our patients are discharged on the third
postoperative day, with average length of stay since
May of 199370f 4 days. Operative time averaged 5 hours
for unilateral reconstructions and 9 hours for bilateral
reconstructions.
The flap survival rate was 99 percent with one flap
failure, not related to the recipient vessels. Successful
repeated reconstruction with the internal mammary recipient
vessels was achieved with a second free perforator flap
using the ipsilateral internal mammary vein at the second
rib level.
Technical Details
The size of the internal mammary vessels at the second,
third, and fourth interspaces was reported recently
by Clark et al.8 They focused on the anatomy of the
internal mammary veins and reported that there were
veins of at least 3 mm in diameter at the second interspace
in 100 percent of the cadaver studies. They also found
that veins of this diameter were found at 33 percent
of the left and 100 percent of the right third spaces.
In their study they found no veins with a diameter greater
than 3 mm at the level of the left fourth intercostal
space, although 60 percent of the right fourth intercostal
spaces had veins greater than 3 mm.
Our measurements of vessel diameter prior to anastomosis
were done with the standard "background grid"
(Table I).
The recipient vein sizes were appropriate for the average
size of the flap vessels (Table II). The veins were
consistently more variable and smaller at the level
of the fourth rib, especially on the left, and we recommend
use of the vessels under the third rib (Fig. 1).
Meticulous dissection of the vessels is critical (Fig.
2). Branches to the intercostal muscle should be dissected
carefully, ligated with small ties, and not coagulated.
It is essential not to avulse these branches in order
to avoid injuring these fragile veins. Every attempt
should be made to expose the vessels from the top of
the lower rib to the bottom of the upper rib. The intercostal
muscle should be removed. Usually 4 cm of a vessel is
exposed and prepared for the anastomosis.
Internal Mammary Vessels
(level of 3rd rib)
FIG. 1. Size match of vessels based on measurements
in our series (n = 110). |
It is also important to allow the vessels to rest and
rewarm for 20 minutes after dissection to allow maximum
dilation of the veins. The veins are quite distensible
(Fig. 3). Great care also must be taken to prevent twisting
during the anastomosis of these long pedicles. The respiratory
motions can be troublesome. We ask the anesthetist to
hand ventilate the patient during the anastomosis and
to occasionally hold the respiration for placement of
the sutures.
Prior to insetting the flap, the skin island is marked
corresponding to the point at which the perforator enters
the undersurface. This reduces confusion about which
vessel is monitored.
Postoperatively, we monitor the flaps with Doppler
ultrasound for artery inflow. Flap color is monitored
for outflow, as is temperature.
Results
Overall flap survival was 99 percent (109 of 110).
However, two early patients in the series required abandonment
of the internal mammary, vein. The vein was injured
during dissection because of inappropriate avulsion
or coagulation of delicate branches. One patient required
a vein graft to the thoracodorsal vein, and a second
was switched to the subscapular system. Thus the internal
mammary vessels were used successfully in 108 of 110
reconstructions (98 percent of patients). Flow from
the internal mammary artery was always brisk and more
than adequate. We did not see any spasm in this vessel.
While the dissection is demanding, it is relatively
straightforward. We have had no stiff shoulders or stretching
injuries to the brachial plexus. None of our patients
were restricted in arm motion following surgery. One
patient was discharged on the first postoperative day
and many on the second day. There was no significant
pain or instability related to resection of the rib
cartilage.
Advantages Over Using the Thoracodorsal Vessels
Breast mound placement can be as medial as desired,
and lateral fullness is rarely encountered, decreasing
the need for secondary flap revision. The dissection
in delayed reconstruction and in irradiated cases is
straightforward. Seven patients in our series had undergone
preoperative radiation, and no radiation effect to the
internal mammary vessels was observed. In bilateral
reconstructions, the two internal mammary vessels can
be exposed simultaneously with minimal repositioning
of the patient or the operating microscope. With some
tilting of the operating table, the first assistant's
position at the microscope is excellent, allowing easy
tying and suturing from either side of the table.
FIG. 2. Typical anatomy of vessels at third rib |
FTC. 4. Markings for superior gluteal artery perforator
|
FIG. 5. Mastectomy defect with internal mammary
artery markings |
FIG. 3. Internal mammary vein-superior gluteal vein
anastomosis |
FIG. 6. Postoperative result |
Complications
Seven patients were returned to the operating room
with postoperative problems. One patient developed mixed
venous/arterial insufficiency that was delayed several
hours in diagnosis. She had been on large doses of selfprescribed
ergotamine preparations prior to surgery for vascular
headaches. She did have a second flap using the ipsilateral
second rib internal mammary vessels to salvage the reconstruction.
Three patients developed venous insufficiency as a result
of twisting of the flap pedicle, requiring revision
of the pedicle position and reanastomosis of the vein.
Two patients developed a hematoma under the flap that
had to be evacuated. One patient had to be returned
for arterial anastomotic problems, and one patient required
surgery for a gluteal hematoma. We had one small pneumothorax
that was treated conservatively and resolved with no
therapy.
Conclusions
We have found the internal mammary system very reliable
for free-flap breast reconstruction (Figs. 4, 5, and
6). Because of the longer pedicle and the ability to
choose an appropriate venous match, the internal mammary
vessels are ideal for the perforator flap.
Utilizing the traditional gluteal myocutaneous flap
still presents a difficult problem because of the size
and shortness of the pedicle and the availability of
only the main superior gluteal vein. Although we have
always dissected the perforator out of the muscle, Shaw9
has recently begun dissecting the pedicle away from
the underside of the muscle in order to obtain more
length and a better match.
In our experience, a satisfactory size match is reliably
found between the internal mammary artery and vein at
the third interspace with the inferior epigastric and
superior gluteal vessels. The internal mammary system
should be brought back into the armamentarium for free
flap breast reconstruction.
Charles L. Dupin, M.D.
120 Meadowcrest Street
Suite 300
Gretna, La. 70056
References
Shaw, W. W. Breast reconstruction by superior gluteal
microvascular free flaps without silicone implants.
Plast. Reconstr. Surg. 72: 490, 1983.
Shaw, W. W., and Ahn, C. Y. Microvascular free flaps
in breast reconstruction. Clin. Plast. Surg. 19: 917,
1992.
Feller, A. M. Free TRAM: Results and abdominal wall
function. Clin. Plast. Surg. 21: 223, 1994.
Allen, R. J., Dupin, C. L., and Class, C. A. Breast
Reconstruction Using the Deep Inferior Perforator
Flaps. Presented at the Annual Meeting of the American
Society of Plastic and Reconstructive Surgeons, New
Orleans, Louisiana, 1993.
Allen, R. J., and Treece, P. Deep inferior epigastric
perforator flap for breast reconstruction. Ann. Plast.
Surg. 32: 32, 1994.
Allen, R. J., Dupin, C. L., and Glass, C. A. Breast
Reconstruction with Gluteal Artery Perforator Flaps.
Presented at the Annual Meeting of the American Association
of Plastic Surgeons, St. Louis, Missouri, 1994.
Allen, R. J., and Tucker, C., Jr. Superior gluteal
artery perforator free flap for breast reconstruction.
Plast. Reconstr. Surg. 95: 1207, 1995.
Clark, C. P., Pittman, C. E., Rohrich, R.J., and Robinson,
J. An Anatomical Study of the Internal Artery and
Vein. Presented at the Annual Meeting of the American
Society for Reconstructive Microsurgery, Marco Island,
1995.
Shaw, W. Breast Reconstruction with Gluteal Free Flaps.
Presented at the Annual Meeting of the American Society
for Plastic and Reconstructive Surgeons, San Diego,
Calif., 1994.
From the Section of Plastic Surgery at the Louisiana
State University School of Medicine. Received for publication
May 30, 1995; revised September 25, 1995.
