1001
Vaginal Reconstruction with Rectus Abdominis Myocutaneous Flap: CT Findings
Steven
J. Willing1’2
American Journal of Roentgenology 1991.156:1001-1004.
Steven Scott Gordon
H. PurselI3 R. Koch1’4 R. Tobin5
The distally based rectus abdominis myocutaneous flap is used in a new technique for vaginal reconstruction after pelvic exenteration for malignant disease. We identified 27 patients who underwent this procedure, of whom eight had a total of 14 postoperative CT scans and two CT-directed biopsies. The myocutaneous flap appeared as a unilateral arcuate band of soft tissue extending from the linea alba to the rectal fascia or sacrum. Additional CT findings included asymmetric thinning of the ventral abdominal wall (7/8), fluid collections (2/8), vaginal breakdown (1/8), presacral soft-tissue thickening (6/8), and tumor recurrence (3/8). The postoperative CT scan reflects the altered anatomy produced by the surgery. Complications and recurrent disease can be recognized as deviations from the normal postoperative appearance. AJR
156:1001-1004, May 199i
Pelvic exenteration for locally advanced or recurrent malignant disease has been shown to improve survival and in some cases to effect a cure [1]. In order to decrease morbidity and improve patients’ acceptance and quality of life, numerous techniques for vaginal reconstruction were developed. One of the more successful techniques has been the bilateral gracilis myocutaneous flap reported by McCraw et al. [2] in i976. Its resultant CT findings were described by Epstein et al. [3] in 1987. In 1 988, Tobin and Day [4] reported their initial results with a distally based rectus abdominis myocutaneous flap for vaginal reconstruction. In this procedure,
a myocutaneous Received September 5, 1990; revision November 21 , 1990.
accepted
after
Presented as a scientific exhibit at the annual meeting of the American Roentgen Ray Society, Washington, DC, May 1990. 1 Department of Diagnostic Radiology, University of Louisville, 2 Present
Louisville, KY 40202. address: Department of Diagnostic
diology, University of Alabama mingham, AL 35233. Address S. J. Willing. 3 Department sity of Louisville,
of Gynecologic Oncology, Louisville, KY 40202.
Univer-
Present address: Department of Diagnostic diology, Emory University, Atlanta, GA 30322. 4
gery,
Department University
Ra-
at Birmingham, Birreprint requests to
of Plastic and Reconstructive Surof Louisville, Louisville, KY 40202.
0361 -803X/91/1 565-1001 © American Roentgen Ray Society
Materials
is constructed
from
the cephalic
portion
of the rectus
and
Methods
We identified 27 patients who had pelvic exenteration with rectus abdominis myocutaneous flap reconstruction in the past 6 years, of whom eight patients had a total of 14 postoperative CT scans and two CT-directed biopsies. The patients ranged in age from 23 to 82 years old (median
Ra-
flap
abdominis, the superior epigastric artery is ligated, and the flap is rotated around its inferior epigastric vascular pedicle and passed through a peritoneal incision into the pelvis (Figs. 1 -3). The advantages of this technique are shortened operative time, improved graft survival, and better obliteration of the pelvic dead space. Patients who have undergone this procedure have a unique postoperative CT appearance, which we describe here.
age,
of the cervix, vagina,
45 years)
at the
time
of the
one had adenocarcinoma
and one
had transitional
procedure.
Five
of the cervix,
cell carcinoma
patients
had
squamous
one had squamous
of the bladder.
The
time
from
carcinoma
carcinoma original
of the diagnosis
ranged from 1 month to 8 years. Six patients had complete exenteration with vaginal reconstruction, one had an anterior exenteration (sparing the rectum) with vaginal reconstruction, and one had exenteration with a rectus abdominis patch but no neovagina to exenteration
was
constructed.
Six patients
were
initially
treated
with
radiation,
and
one
patient
was
treated
i 002
WILLING
initially
with
both
initially
with
exenteration
Fourteen Four
and
were
One
One
in the
patients
and
from
2 to
ranging
patient
by postoperative first
treated
Results
were reviewed.
Normal
postoperative
six additional 17 months
was
month
\.
May 1991
patients after
Postoperative
had
follow-
surgery.
,
I
The muscular flap most often is seen as a unilateral arcuate band of soft tissue extending from the linea alba to the sacrum (Fig. 4) or, in the case of anterior exenteration, to the perirectal fascia (Fig. 5). It may be situated on either side of the pelvis. The flap may also lie in a more posterior position, anterior to the sacrum and nearly midline in position (Fig. 6). The cutagraft
forms
the
neovagina,
completely
encircled
by a
of fat (Fig. 5). As reported after gracilis reconstruction, air may be seen in the neovagina and is a normal finding. Intravaginal air, when present, permits visualization of both layer
I
!!
Appearance
in two
neous ‘
AJR:156,
irradiation.
CT scans
abdominopelvic
obtained
of these
up examinations
hysterectomy.
followed
postoperative
scans
patients.
radiation
ET AL.
‘I
inner
and
outer
walls.
and only the outer vagina is redundant,
Otherwise,
the inner
walls
are apposed
wall is visible. The skin forming the neoand tends to collapse into a linear or “V’
configuration. A
B
American Journal of Roentgenology 1991.156:1001-1004.
Fig. 1.-A,
Myocutaneous
C flap is created,
based on inferior
epigastric
vascular pedicle. B, Skin of flap is wrapped
C, Flap with neovagina laparotomy
and donor
to form neovagmna. is passed into pelvis and secured
to perineum;
site closed.
Seven of the eight patients exhibited asymmetric thinning of the ventral abdominal wall at the graft donor site (Fig. 7A). Here the posterior rectus fascia forms the remaining abdominal wall support. This area is at risk for hernia formation, but the reported prevalence is only about 3% [5]. No hernias were present in this select group of patients. Presacral soft-tissue thickening was seen in six patients (Fig. 6). This is usually attributable to the muscular flap. Only one of the six had recurrent tumor in the presacral space. In this
case,
smooth --q
:
“F
markedly
4 months
Abnormal
CT Findings
One
Fig. 2.-Cross
early
postoperative
of presacral
soft
scans
tissue,
showed
which
a thin,
had thickened
later.
‘-‘
R
wrapped abdominis
the
band
section
to form neovagina. muscle.
of flap illustrates how myocutaneous flap is S = skin, F = subcutaneous fat, R = rectus
obese
separation pelvic fluid resolved died
of
that
patient
had
healed
collection
during
spontaneously recurrent
a superficial
uneventfully. 8A);
however,
Breakdown
of
wound
patient
the first postoperative
(Fig. tumor.
abdominal
Another
had
month
a
that
she subsequently the
neovagina
oc-
Fig. 3.-A, Sagittal view of reconstructed pcIvis. I = neointroitus, S = pubic symphysis. B, Cut-away view of reconstructed pelvis, viewed from perineum. A = aorta, E = external
iliac artery, I = inferior epigastnc artery. R = rectus abdominis graft, F = subcutaneous fat, V = neovagina. A
B
AJR:156,
CT
May 1991
Fig. 4.-23-year-old cell carcinoma
of vagina.
first month after surgery
OF
VAGINAL
RECONSTRUCTION
1003
woman with squamous CT scan obtained in
shows curvilinear
of soft tissue from linea alba to sacrum due to muscular graft.
band
(arrows)
American Journal of Roentgenology 1991.156:1001-1004.
Fig. 5.-34-year-old woman with carcinoma of cervix, 6 months after anterior exenteration and reconstruction. CT scan shows rectus abdominis forming a soft-tissue band from linea alba to rectal fascia (arrows), surrounding neovagina. Neovagmna is formed by grafted skin (arrowheads) surrounded by subcutaneous fat (asterisk).
Fig. 6.-54-year-old
woman with squamous
car-
cinoma of cervix, 17 months after exenteration and reconstruction. CT scan shows presacral, midline band of soft-tissue density due to muscular patch.
in one patient, indirectly identifiable extraperitoneal collection of free air in the Postoperative abscess occurred in one had a postoperative course complicated struction and jejunal perforation leading curred
Fig. 7.-A, 32-year-old woman with adenocarcinoma of cervix. CT scan obtained 10 months after exenteration and reconstruction for carcinoma of cervix shows a normal graft donor site. There is asymmetric thinning of left abdominal wall due to removal of rectus abdominis. Left kidney is hydronephrotic. B, Biopsy-proved recurrent tumor (arrows) causes convex bulge on normally concave inner border of muscular flap. Note neovagina (arrowheads) surrounded by fat.
on CT as a large pelvis. patient. This patient by small-bowel obto a large abscess
containing air and fluid in the anterior perihepatic Pathologically confirmed tumor recurrence was
space.
identified in three patients. In the first case, follow-up scans showed omental tumor mass and a heterogeneous pelvic soft-tissue mass lateral and posterior to the flap extending to the piriformis muscles and sacrum (Fig. 8B). The second patient developed a focal soft-tissue mass altering the normal crescentic inner margin of the myocutaneous flap 1 0 months after reconstruction (Fig. 7B). A CT-guided needle biopsy was diagnostic for recurrent tumor. In the third case, recurrent pelvic tumor was visible as a soft-tissue mass with central low attenuation abutting the wall of the neovagina.
Discussion Although pelvic exenteration can significantly improve the survival rate (up to a SO% 2-year survival rate) for patients with gynecologic malignant tumors, it is not without morbidity. The
loss of pelvic soft tissue allows bowel herniation
into the
pelvis with the danger offistulization and obstruction. If further radiotherapy is required, bowel may be in the therapy field. The loss of sexual function affects the patient’s postoperative quality of life and acceptance of the procedure. In order to address these issues, pelvic soft-tissue packing and vaginal reconstruction have been performed by using a variety of techniques. The bilateral gracilis myocutaneous flap has commonly been used; however, the distally based rectus abdommis myocutaneous flap has certain advantages and is finding increasing acceptance. These advantages include improved graft survival and shortening of the operative time.
1004
WILLING
ET AL.
AJR:156,
May 1991
American Journal of Roentgenology 1991.156:1001-1004.
Fig. 8.-A, 50-year-old woman with squamous carcinoma of cervix. CT scan obtained in first postoperative month shows pelvic fluid collection surrounding graft. This resolved spontaneously. Note air in neovagmna (arrow), rectus abdominis (arrowheads), and layer of subcutaneous fat (asterisk). B, CT scan obtained 6 months later. Note marked increase in amount of presacral soft tissue.
The procedure begins with the design of a 1 0- to 1 2-cmwide ellipse of skin beginning below the costal margin and extending a few centimeters below the umbilicus. The caudal end is extended into the laparotomy incision to allow a single closure. After the skin incision, the cephalic margin of the rectus abdominis is transected and the superior epigastric artery is ligated. A tube is created with the cutaneous portion of the graft to form a neovagina. The cephalic end is left open, to form the new introitus. The completed pouch is passed through a peritoneal incision into the pelvis, and the rectus fascia
is closed
to prevent
hernia.
Care
is taken
in the
series.
activity vagina
reported successful orgasms even though the neois insensate. Our series of CT evaluations in this group
yielded
the
following
patients
observations.
who
(1)
resumed
The
unilateral
thinning
tissue thickening Recurrent tumor normal
configuration
fat with inner cutaneous lining. be seen in most patients as of the rectus sheath. (4) Presacral softcan be a normal postoperative finding. (5) appears as a soft-tissue mass altering the of the reconstructed
pelvis,
possibly
with
abnormal enhancement or tissue inhomogeneity. (6) Familiarity with the normal postoperative appearance is necessary both for the detection of recurrence and to avoid a falsely positive diagnosis.
throughout
to preserve the inferior epigastric vascular pedicle supplying the graft. In Tobin and Day’s series, there was complete graft survival in 1 8 of 20 patients. The remaining two had partial losses that were successfully revised. In these two, the paddles had been extended above the costal margin. Subsequently, the cephalic extent of the paddle was limited to just below the costal margin. No hernias or postoperative infections occurred Interestingly,
configuration of subcutaneous (3) The graft donor site can
muscular
sexual
flap
appears as a band of soft-tissue density abutting the pelvic side wall or sacrum. (2) The neovagina exhibits a doughnut
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malig-
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myocutaneous
flaps.
Plast Reconstr Surg 1976;58: 176-183 D, Mintz MC, Coleman BG. CT evaluation vaginal reconstruction after pelvic exenteration.
3. Epstein DM, Arger PH, LaRossa
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1989:55:632-637