 |
|
Dacron Implants in Rhinoplasty
A Review of 136 Cases of Tip and Dorsum Implants
Nabil Fanous, MD, FRCSC;
Mark Samaha, MD;
Adi Yoskovitch, MD, MSc
Arch Facial Plast Surg. 2002;4:149-156.
ABSTRACT
The achievement of successful results in rhinoplasty may require the
use of autografts, homografts, or alloplastic materials. Among the alloplasts,
Dacron is an easily handled and manipulated synthetic material, readily applicable
to nasal augmentation. The following represents the indications, surgical
technique, outcome results, and analysis of our experience with Dacron mesh
implants to the nasal tip, dorsum, and lateral walls in 136 patients.
INTRODUCTION
The goal of an optimal aesthetic result in rhinoplasty may necessitate
the use of grafts or implants. The different categories of materials used
to achieve this consist of autografts, homografts, and alloplasts. The most
common autografts used in rhinoplasty include septal cartilage and bone, conchal
cartilage, and costal cartilage and bone. Although preferred by several researchers
for their biocompatibility, bone and cartilage autografts may be associated
with certain complications, particularly the predictability of the aesthetic
result.
Several types of alloplastic materials have been, and continue to be,
used for dorsal and tip augmentation in rhinoplasty.1-11
We believe implants have a valuable role in rhinoplasty, provided the right
implant material is chosen and the correct technique is used for the proper
indication. Some different types of alloplastic implants used in rhinoplasty
are as follows: polytetrafluoroethylenes, the most common being Gore-Tex (W.
L. Gore Associates, Inc, Flagstaff, Ariz); silicone rubber (such as Silastic);
polyethylene, such as Medpore (Porex, Fairburn, Ga) and Plastipore (Richards
Manufacturing Company, Memphis, Tenn) and polyesters and polyamides, such
as Dacron (Ethicon Inc, Somerville, NJ), Mersilene (Ethicon Inc), Supramid7 (S. Jackson Inc, Alexandria, Va), and the Cooley Dacron
knitted implant (Meadox; Boston Scientific, Quincy, Mass). Dacron material
implants have been extensively used in cardiovascular surgery, with the results
of many long-term follow-up studies reported in the medical literature.12-17
Dacron fabric (Cooley) is a polyethylene terephthalate woven into a tight
nonresorbable mesh. It is a multifilament fabric supplied as a white fabric
sheet. Its design allows minimal tissue ingrowth that is enough to maintain
the implant position. The multifilament arrangement makes the implant not
slippery during surgery; therefore, it stays wherever it is placed and almost
sticks to its bed or to the overlying skin. In addition, this implant may
be handled, cut, and shaped easily while retaining a certain degree of body.
It does not shred, as encountered with other Dacron-type materials, such as
Mersilene mesh. In addition, its soft nature makes it difficult to detect
by skin palpation or visual inspection, even years after being implanted.
One of us (N.F.) reported his experience with 98 cases of tip augmentation
using Dacron mesh (Mersilene mesh) in 1991.2
Subsequent to this, our use of Dacron has moved from the looser mesh form
(Mersilene) to the fabric form (Cooley) because of the latter's further ease
of intraoperative manipulation and minimal shredding. However, this advantage
of the fabric form is minimal. As far as clinical results are concerned, both
Dacron materials are identical.
We present herein our experience in using Dacron alloplastic materials,
mostly the fabric form, to augment and shape the tip, dorsum, and lateral
walls in 136 patients undergoing rhinoplasty.
PATIENTS AND METHODS
PATIENTS
A retrospective analysis was performed, reviewing the results in 136
patients who underwent rhinoplasty with augmentation using Dacron implants.
The indications for dorsum augmentation were a deep nasofrontal angle, a saddle
deformity of the dorsum, or a depressed supratip area. Dorsal saddle deformity
was the most common indication of dorsal correction.
Indications for tip augmentation were previously detailed.2
The 2 most common indications were a recessed tip and a wide tip.
The implant may also be used in the lateral wall to augment a depression,
typically in cases of side-to-side nasal pyramid deviation.
All patients included in this study were asked several months postoperatively
to rate their degree of satisfaction with the cosmetic result. The results
were graded as very happy (n = 68), happy (n = 59), satisfied (n = 4), and
dissatisfied (n = 5). The surgeon, at that same time, rated his own assessment
of the aesthetic result. The different grades were very good (n = 64), good
(n = 40), satisfactory (n = 24), and unsatisfactory (n = 8).
TECHNIQUE
Tip Augmentation
The technique used for tip implantation was previously described in
detail2, 7 by one of us (N.F.).
Several critical points and some minor modifications will be emphasized. The
fabric material (Cooley) is first folded onto itself to form a pad that is
2 to 8 layers thick and approximately 1 cm in width (from left to right) and
8 mm in height (from superior to inferior). The thickness of each layer is
approximately 0.5 mm. Therefore, a 2-layer implant is approximately 1 mm thick,
and an 8-layer implant is approximately 4 mm thick. The implant is shaped
like either a lozenge (10 mm in width x 7 mm in height) (Figure 1A) or a triangle (10 mm [base] x 5 mm x 5 mm,
with the apex pointing downward). The triangular shape is used often in cases
of thick nasal skin with poor definition. Depending on the degree of tip recession,
2 to 8 layers (1-4 mm) may be used. Typically, the most common thickness used
is 4 to 6 layers. A central through-and-through catgut suture is used to hold
the layers together.
|
|
|
|
Figure 1. Technique of tip augmentation.
A, Preoperative planning: the implant contour is marked over the skin of the
tip, making sure that line ab of the implant is at the level of the tip-defining
point in the profile view. B, Incision. C, Pocket dissection in the frontal
and profile views. D, Introduction of the implant in the pocket. E, Making
sure line ab (at the end part of the hemostat) is horizontal, then stabilizing
gently the upper and lower borders of the hemostat, before opening and retracting
it.
|
|
|
After outlining the position of the implant on the nasal tip preoperatively
(Figure 1A), a rim incision of 1.0
to 1.5 cm is made along the caudal border of the right alar cartilage (Figure 1B). Dissection of a subcutaneous
pocket, slightly larger than the size of the implant, is then performed (Figure 1C). The implant, soaked in bacitracin
solution, is held horizontally with a curved mosquito clamp, making sure that
the end of the mosquito clamp is horizontally placed across the implant and
that the tip of the instrument is on the left end of the implant (Figure 1D). The implant is then inserted
while pulling the right alar rim up using a double-sharp hook and while pushing
the alar cartilages down with blunt scissors. The tip of the curved mosquito
clamp is positioned at point b under the skin (Figure 1E), and the implant is aligned horizontally over the line
ab. The upper and lower parts of the implant are then stabilized gently, with
the fingers placed above and below the curved mosquito clamp over the skin;
then, the mosquito clamp is widely opened and slowly withdrawn. One 6-0 catgut
suture is placed at the midpoint of the incision for approximation.
Dorsum Augmentation
The superior and inferior ends of the long axis of the implant are marked
superiorly and inferiorly on the skin of the nose along the midline (Figure 2). In the event the dorsal depression
is deeper on one area (typically the middle of the dorsum at the level of
the rhinion), a third mark is placed on the skin at that site to identify
the area of maximum implant thickness. In general, the length of the implant
varies from 2.5 to 3.5 cm, the width from 8 to 10 mm, and the thickness from
2 to 6 layers (1-3 mm). In some instances, the thickness may be greater than
6 layers. The implant may be uniform in thickness or may have an area of greater
thickness, as previously indicated. The implant is then shaped in the following
manner: the upper and lower ends of the implant are made triangular to ensure
a gradual tapering of the implant ends. This avoids an abrupt step deformity
after the swelling subsides postoperatively. Also, the implant sides, namely,
the left and right borders, are tapered (angled) for the same purpose. If
one area of the implant (eg, the central third) is thicker than the rest,
a second implant is calculated, measured, and tapered like the first main
implant. The shorter implant is then placed under the longer one, and an additional
through-and-through catgut suture is used to attach both implants together.
|
|
|
|
Figure 2. Dorsal and lateral wall implants:
the frontal view demonstrates the shape of the implants, their tapered ends,
their relative size compared with the pockets, and their central sutures.
The access incision to each pocket is marked by heavy dots. The transverse
section shows the side beveling of the implants, which is facing outward in
the case of a dorsal implant and inward in the case of a lateral wall implant.
|
|
|
If the dorsal dissection has not been completed, a 1.5-cm incision is
made on the medial end of the right intercartilaginous incision at the area
of the septal angle (Figure 2).
A subcutaneous or supraperichondrial supraperiosteal pocket is dissected along
the dorsum. The layers of the prepared dorsal implant are usually sutured
about the center or at both ends with 4-0 chromic transfixion sutures to hold
the layers together (Figure 2).
The implant is then placed between the 2 sides of an angled nasal bayonet
forceps, ensuring that the superior end of the implant is exactly at the closed
tip of the angled forceps. An Aufricht dorsal retractor is used to elevate
the dorsal nasal skin, while a curved mosquito clamp is used to retrieve and
pull down on the lower edge of the intercartilaginous incision for better
entry (Figure 3). The angled forceps
embracing the implant is then introduced slowly within the dorsal skin pocket,
sliding against the Aufricht elevator (rather than against the dorsum), until
it reaches the upper mark on the nasal skin. The Aufricht retractor is then
moved slowly backward and removed. The fingers of the left hand are placed
gently on either side of the implant. The angled forceps is opened widely
and then slowly retraced backwards, using a gentle rocking motion to avoid
implant retraction or displacement during this maneuver. The incision is then
inspected to ensure that the lower end of the implant is positioned at least
4 mm away from the closure site. A single 4-0 chromic suture is then used
to close the incision.
|
|
|
|
Figure 3. Introduction of the dorsal implant
into the dorsal pocket.
|
|
|
Lateral Wall Augmentation
An incision is made through one or both intercartilaginous folds, depending
on whether the depression is unilateral or bilateral. The implant marking,
preparation, and insertion are similar to that described for the dorsum. However,
the implant is typically much thinner, varying between 1 and 2 layers (0.5-1.0
mm). For lateral wall augmentation, 50% undercorrection is the rule, as the
slightest overcorrection will be extremely noticeable a few months postoperatively.
The shape is again triangular and tapered if more than one layer is used.
In rare cases, when the lateral wall depression extends inferiorly beyond
the lower border of the upper lateral cartilage, the access incision may be
made intracartilaginous through the alar cartilage. This is because the incision
to the pocket has to be at least 4 mm inferior to the implant.
RESULTS
This series consisted of 92 women and 44 men, for a male-female ratio
of 1:2.1. The mean ± SD age of the patients was 26.5 ± 7.5 years
for men and 28.9 ± 9.4 years for women. All rhinoplasties were performed
by the same surgeon (N.F.). In 88 (65%) of the 136 procedures, only the tip
was augmented, while in 45 (33%) of the patients, the tip and the dorsum or
lateral walls were augmented. In 3 instances (2%), Dacron was used on the
dorsum only.
All patients were prescribed intraoperative antibiotics: intravenous
cefazolin, 1 g, when an allergy to penicillin was ruled out or intravenous
erythromycin in the cases of penicillin allergy. All patients were treated
with oral antibiotics (such as erythromycin) for 1 week postoperatively for
further prophylactic coverage.
The follow-up ranged from 7 months to 12 years (average, 37 months).
The same operating surgeon (N.F.) performed the follow-up and assessment. Figure 4, Figure 5, Figure 6, Figure 7, Figure 8, Figure 9, and Figure 10 show examples of preoperative
and postoperative results of Dacron implantations in various patients (lateral
wall implants in Figure 4; dorsum
and supratip implants in Figure 5;
implants in a patients who underwent revision rhinoplasty in Figure 6; dorsal implant thickest at the nasofrontal angle superiorly
in Figure 7; dorsal implant of equal
thickness in Figure 8; tip implant
only, representing the most common implant indication, in Figure 9; and long-term results in Figure 10).
|
|
|
|
Figure 4. A and B, Preoperative views of
a 29-year-old man with a narrow bony bridge and concave upper lateral walls
more on the left side than on the right, a recessed upper dorsum, thick redundant
skin at the supratip and tip areas, and a drooping nasal tip. C and D, Postoperative
result 2 years 4 months following a rhinoplasty with lateral wall implants
(just 1 layer on the right and 2 on the left) and dorsal and tip implants.
|
|
|
|
|
|
|
Figure 5. A and B, Preoperative views of
a 29-year-old woman with a low dorsum and thick skin at the tip and supratip.
C and D, Postoperative results 11 months following rhinoplasty with a dorsal
implant thickest at the supratip area because of a resistant skin concavity
at that area. A tip implant was also used.
|
|
|
|
|
|
|
Figure 6. A and B, Preoperative photographs
of a 20-year-old man with a history of 3 previous septorhinoplasties. He presented
with a turned-up asymmetrical tip, a recessed dorsum, and lateral wall depressions,
more obvious on the left. C and D, Postoperative results 7 years 2 months
following a revision rhinoplasty with dorsal, tip, and left lateral wall Dacron
(Ethicon Inc, Somerville, NJ) implants.
|
|
|
|
|
|
|
Figure 7. A and B, Preoperative photograph
of a 33-year-old man with a recessed ill-defined nasal tip, a low upper dorsum,
and very thick nasal skin. C and D, Postoperative results 2 years 10 months
following a rhinoplasty with a dorsal implant (thicker at the root of the
nose) and a nasal tip implant.
|
|
|
|
|
|
|
Figure 8. A and B, Preoperative photographs
of a 27-year-old man with a projecting tip and a low dorsum. C and D, Postoperative
results 12 months following a rhinoplasty with a dorsal implant of uniform
thickness and a tip implant.
|
|
|
|
|
|
|
Figure 9. A and B, Preoperative views of
a 22-year-old woman who is a typical example of a nose surgery candidate with
a dorsal hump and a somewhat wide nasal tip. C and D, Postoperative photographs
15 months after a regular rhinoplasty combined with the placement of a tip
implant to achieve a well-defined yet natural-looking nasal tip. This case
is a typical example of the use of the Dacron (Ethicon Inc, Somerville, NJ)
nasal tip implant, which is more often used in the nasal tip than in the dorsum
or lateral walls.
|
|
|
|
|
|
|
Figure 10. A and B, Preoperative views of
a 28-year-old woman with a low dorsum and a prominent and very boxy nasal
tip. C and D, Very long-term postoperative result 11 years 2 months after
the use of Dacron (Ethicon Inc, Somerville, NJ) implants in the dorsum and
tip areas.
|
|
|
The most significant complication was infection, which occurred in 9
(6.6%) of the patients. In all cases, the patient was immediately given oral
antibiotics on diagnosis of the infection, and the implant was removed under
local anesthesia as soon as possible. Removal of the implant was always performed
without difficulty because there was little tissue infiltration or fibrous
attachment in all of the patients with infection. In the case of a tip implant,
a curved mosquito clamp is used to retrieve the implant through a small rim
incision. In the case of a dorsal or lateral wall implant infection, the same
technique is used through an intercartilaginous incision, but more dissection
is required. It is important to accurately count the number of layers removed
to ensure complete removal of the implant.
Ten implants were removed in these 9 patients. Eight were tip implants,
and 2 were dorsal implants. In a single instance, tip and dorsum implants
were removed. In all patients, the infection resolved within days of implant
removal. Of the 9 patients, 6 underwent another procedure during which a second
Dacron implant was inserted. The remaining 3 patients declined a second surgery.
(It has been our experience that after implant removal, the area previously
receiving the implant seems to retain a mild degree of augmentation. We have
no explanation as to why this happens, but it could theoretically be due to
granulation tissue formation as a reaction to the implant or the infection.)
A diagnosis of implant infection was based on purulent discharge at
the site of the pocket incision, in addition to one or more of the following
signs: swelling, tenderness, redness, or extrusion. The presence of discharge
is definite proof of implant infection. In the absence of discharge, the patient
is given antibiotics and checked almost daily to rule out the small possibility
of a limited skin infection (eg, furuncle) not involving the implant.
Two patients underwent revision because of an unsatisfactory aesthetic
result, where a tip implant had migrated slightly to the right and a dorsal
implant was too thick. This was remedied under local anesthesia by trimming
a portion of the implant, a somewhat tedious procedure. The noninfected implant
is usually well attached to the skin and underlying structures. Dissecting
the implant off the overlying skin is easier than freeing it from the underlying
cartilage or bone. The surgeon may choose 1 of 3 approaches: (1) trim the
excess (the hardest to do, because the implant is well integrated and the
Cooley fabric is difficult to cut when invaded with granulation tissue); (2)
remove the entire implant and replace it with a brand new one (the easiest
approach); or (3) remove the implant, reshape it, and reinsert it (the only
problem is fixing it in place, because it tends to be slippery).
COMMENT
Dacron fabric allografts are among the myriad of options available in
rhinoplastic surgery. Although potential postoperative infection is a disadvantage,
Dacron fabric implants are particularly desirable to use in many cases of
augmentation rhinoplasty. In terms of the aesthetic result, they have several
advantages, the most important of which is having an impressive natural appearance
and feel that are hard to detect by either visual examination or manual palpation.
They display no tendencies for curling or resorption over time9, 11
and are unlikely to undergo displacement. In our series, no cases of resorption
or implant distortion were observed. In addition, there is no donor site morbidity.
Dacron fabric can be molded to assume any shape or thickness required, providing
a controllable and smooth contour. The amount of available material is unlimited.
Decreased surgical time contributes to lower morbidity and lower cost. Finally,
Dacron has been used extensively as a cardiovascular implant and has an excellent
long-term record.12-17
Other implantable materials commonly used have similar advantages, but
certain drawbacks make them less desirable. Silastic, for example, a silicone
rubber, has a firm consistency, therefore tending to feel like a foreign body
under the skin. Also, it lacks pores, impeding tissue ingrowth and possibly
contributing to implant displacement. Its surface is slippery, which may lead
to malpositioning and which makes it hard to handle intraoperatively. Gore-Tex,
which has been used in nasal augmentation,6-8
also tends to be slippery, causing possible displacement in the initial postoperative
period, before tissue ingrowth has taken place. In addition, Gore-Tex has
a whitish color, which may become visible externally, particularly in thin-skinned
individuals and particularly in the long term after postoperative edema has
subsided.
Dacron is not without its drawbacks, the most significant of which is
infection.1 Others include asymmetry and incorrect
implant volume, both mostly related to the surgeon's experience using the
material. This experience is quickly acquired if the guidelines suggested
earlier in this article, regarding the implant's thickness range, shape, tapered
edges, access incision, and insertion technique, are vigorously followed.
The incision needs to be large enough (1.5 cm) to allow good exposure, dissection
of a pocket, and easy implant introduction. It should be closed loosely to
allow any serous discharge or bleeding to drain, rather than remain confined
within the pocket and progress to abscess formation. The pocket needs to be
approximately 50% larger than the size of the implant because it will eventually
contract. If it is not sufficiently large, it will result in subsequent implant
infection or extrusion.
Our complication rate of infection is comparable to previously reported
rates of 4% to 9%.4, 7 However,
this drawback is tempered by the many advantages associated with the use of
this material. The high cosmetic reliability and quality of the result are
often understated in the literature. Although cartilage grafts are rarely
infected, they have cosmetic problems, including resorption, displacement,
curling, and sharp edges. The longer the postoperative follow-up, the more
evident some of these problems will become, especially those related to curling
and sharp edges and those in medium- to thin-skinned patients.
AUTHOR INFORMATION
Accepted for publication January 22, 2002.
We thank Ildico Horvath, medical artist, for her assistance in preparing
the figures; Robert Derval, medical photographer, for his photographic contributions;
Barbara Armbruster, MA, for her help in editing; Lucie Roy and Stephanie Luetticken,
MBA, for organizing the manuscript; and Jackie Griguolo and Derya Atilgan
for their typing assistance.
Corresponding author and reprints: Nabil Fanous, MD, FRCSC, Department
of Otolaryngology–Head and Neck Surgery, McGill University, 1 Westmount
Sq, Suite 1380, Montreal, Quebec, Canada H3Z 2P9.
From the Department of Otolaryngology–Head and Neck Surgery,
McGill University, Montreal, Quebec.
REFERENCES
| |
1. Constantino PD. Synthetic biomaterials for soft tissue augmentation in the head and
neck. Otolaryngol Clin North Am. 1994;27:223-262.
WEB OF SCIENCE
| PUBMED
2. Fanous N. Mersilene tip implants in rhinoplasty: a review of 98 cases. Plast Reconstr Surg. 1991;87:662-673.
WEB OF SCIENCE
| PUBMED
3. Beckhuis GJ. Mersilene mesh to augment the nasal bridge. Am J Cosmetic Surg. 1986;3:49.
4. Colton JJ, Beckhuis GJ. Use of Mersilene mesh in nasal augmentation. Facial Plast Surg. 1992;8:149-156.
FULL TEXT
| PUBMED
5. Mendelsohn M, Dunlop G. Gore-Tex augmentation grafting in rhinoplasty: is it safe? J Otolaryngol. 1998;27:337-341.
WEB OF SCIENCE
| PUBMED
6. Shoenrock LD, Chernoff G. Subcutaneous implantation of Gore-Tex for facial reconstruction. Otolaryngol Clin North Am. 1995;28:325-340.
WEB OF SCIENCE
| PUBMED
7. Fanous N, Webster R. Supramid tip implants in rhinoplasty. Arch Otolaryngol Head Neck Surg. 1987;113:728-736.
FREE FULL TEXT
8. Lovice DB, Mingrone MD, Toriumi DM. Grafts and implants in rhinoplasty and nasal reconstruction. Otolaryngol Clin North Am. 1999;32:113-141.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
9. Silver WE, Goldberg J. Nasal grafts and implants. Facial Plast Surg Clin North Am. 1994;2:477-499.
10. Kridel RWH, Kraus WM. Grafts and implants in revision rhinoplasty. Facial Plast Surg Clin North Am. 1995;3:473-486.
11. Maas CS, Monhian N, Shah SB. Implants in rhinoplasty. Facial Plast Surg. 1997;13:279-290.
FULL TEXT
| PUBMED
12. Phillips CE, DeWeese JA, Campeti FL. Comparison of peripheral arterial grafts: experimental observations
of hemodynamic changes using cineangiography. Arch Surg. 1961;82:58-68.
13. Szilagyi DE, Smith RF, Elliott JP, Allen HM. Long-term behaviour of a Dacron arterial substitute: clinical, roentgenologic
and histologic correlations. Ann Surg. 1965;162:453-477.
WEB OF SCIENCE
| PUBMED
14. Cooke PA, Nobis PA, Stoney RJ. Dacron aortic graft failure. Arch Surg. 1974;108:101-103.
FREE FULL TEXT
15. Edwards WS. Arterial grafts of Teflon. In: Sawyer PN, Kaplitt MJ, eds. Vascular Grafts. New York, NY: Appleton Century Crofts; 1978:173-176.
16. Noon G, DeBakey M. De Bakey Dacron Prosthesis and Filamentous Velour
Grafts: Vascular Grafts. New York, NY: Appleton Century Crofts; 1978:177-184.
17. Edwards WS. Dilatation and durability changes in synthetic grafts of Dacron and
Teflon. In: Bernhard VM, Towne JB, eds. Complications in
Vascular Surgery. New York, NY: Grune & Stratton Inc; 1980.
|
