tissue expander

1. Tissue Expanders in Reconstruction of
Maxillofacial Defects
Jacob John • Joseph Edward • Joju George
Dr. Darshana D Gawande
P.G. 2nd year

2. • Reconstructive Maxillofacial Surgery is a highly dynamic
disciplined branch of Oral and Maxillofacial Surgery that
relies on traditional surgical skills as well as surgical
innovations in order to cope with the challenging
management of congenital, acquired defects and residual
deformities of Maxillofacial region.
• The ability of our tissues to stretch and expand gradually
over time has been observed and documented, both in
physiological and pathological situations, throughout
medical history.
Introduction

3.  The observation that living tissues respond in
dynamic fashion to mechanical forces placed upon
them has been applied to the clinical problem of
surgical defects; the technique of tissue expansion,
has provided great advantages to the surgeon and
patient.
 This technique has improved the ability of the
surgeon to replace lost or surgically excised tissue
with neighboring tissue of similar color, texture,
sensation, and thickness.

4. How does the tissue expansion yield extra tissue?
Tissue expansion technique exploits the adaptability
quality and induces a controlled in situ skin growth.
Stretches beyond the skin’s physiological limit, invoke
several Mechano-transduction pathways, which increase
mitotic activity and collagen synthesis, ultimately resulting
in a net gain in skin surface area

5.  The physiology of expansion by prolonged tissue
expansion is not just a matter of stretching skin, but the
actual formation of additional new skin which has all the
attributes of the original tissue.
 Austad et al. postulate that tissue expansion causes a
decrease in cell density in the basal layer of the skin and
that cell density may regulate skin mitotic activity . A
lower cell density results in a greater cell proliferation,
resulting in growth of additional skin.
 Inflation of the tissue expander was found to cause a
threefold elevation of epidermal mitotic activity within 24
h, followed by a gradual return to normal baseline over
2–5 days.

6. Conversely, deflation of the expander caused a
transient decrease in epidermal mitotic activity.
The increase in mitosis returns to normal 4 weeks
after expansion. On histologic studies, the
epidermis has an increase in its thickness and the
rete pegs become flattened when compared to
nonexpanded skin

7. Capsule
 A capsule forms around the expander as with most foreign
body reactions.
 These capsules are thickest after 2–2.5 months of expansion.
 Within 7 days there is a 2 layer capsule consisting of an inner
layer of macrophages and an outer layer of fibroblasts and
some lymphocytes.
 Over time the outer layer becomes richer in collagen fibers.
The bordering layer around the capsule becomes richly
vascularized.
 Once an expander is removed, the surrounding fibrous capsule
rapidly thins.

8. Biological effects of tissue expansion
Thickening of epidermis
 Thinning of dermis
 Alignment of collagen fibrils
 Improved vascularity
 Bone deformation
Periosteal reaction

9.  Soft tissue expansion before vertical ridge augmentation.
INDICATIONS

10. CLEFT LIP & PALATEREPAIR.

11. Correction of post traumatic or postoperative alopecia

12. Treatment of male pattern
baldness

13. Expansion of forehead skin prior to forehead flap total
nasal reconstruction

14. Expansion of postauricular skin prior to reconstruction
of the external ear

15. Expansion of cheek or neck skin to allow scar
revision, burn excision.

16. Breast reconstruction.
 Alternative to reconstructive methods
Difficult decubitus ulcers

17. Contraindications
• Active infection anywhere in the body.
• Clinically persistent or recurrent cancer.
• Poor vascularization of tissue in the area where the
implant is to be used
• History of compromised wound healing.
• Compromised immune system.
• History of sensitivity to foreign materials

18. Expanders

19. A device consists of a
silicone elastomer
inflatable expander with a
remote injection dome.
The expander and remote
injection dome are for
temporary subcutaneous or
submuscular implantation
and is not intended for use
beyond six months.
Parts of a Silicone Tissue
Expander

20.  Expanders are available in round, rectangular,
elliptical and crescent shape with a smooth
elastomer shell.

21. Expander selection
Selection of shape of the expander – Area tobe
reconstructed should be cosidered
 Covering a large defect in Head & Neck region –
Rectangular expander is preferred
 Round defects – Crescent shape is preferred
Expander base should be 2.3 to 3 times the surface area
of the defect to be closed

22.  If the overlying skin is scarred and unstable, a
deeper plane is chosen to ensure sufficient skin
vascularity and integrity to withstand the stresses of
the expansion.
 If the skin is thick and relatively more resistant to
soft-tissue stretch, the plane could be more
superficial.
 An avascular plane or a plane which minimises
bleeding during pocket dissection is infinitely
preferable
 The plane of this dissection should be such that it is
superficial enough for easy palpation and yet deep
enough to avoid pressure necrosis of the skin from
the hard valve surface and edges.

23. Technique
 Tissue expanders are implanted using L.A or G.A.
Preoperative planning of incision site and orientationof
implanted expander are important.
Incision is made in an area adjacent to the area to be
reconstructed
The Expander is placed beneath the subcutaneous layer of
skin on muscle or bone.
For Scalp expansion the Expander is placed in subgaleal
pocket leaving pericranium intact.

24. The injection port of the tissue expander is placed in a
separate subcutaneous tissue pocket in the same incision.
The port should be easily palpated & accessible for
saline injections.
The access incision after implanting the tissue expander
is closed in layers.
After closure of incision the Expander may be injected
with saline to obliterate the remaining dead space.
To allow for sufficient healing, inflation of expander is
commenced 2 weeks after implantation.

27. “Rule of 10” for filling of the tissue expander
 10% filling is performed intra-operatively,
 Postoperative filling is started at the 10th postoperative day,
 1/10th of the total capacity is filled in each filling session,
 The entire filling process is completed over 10 weeks,
10% overfilling beyond the prescribed capacity is routinely
performed

28. • A 24 year old female patient
presented with complaints of
scar and fistula over right side of
her face since 18 years and
associated complaints of oozing
of saliva and food debris from
site.
• History of Acute Lymphocytic
Leukemia was diagnosed at the
age of 5 years for which she
underwent chemotherapy at the
age of 6 years.

29. • During and after chemotherapy she had pain in
lower gums which manifested as mucositis and
following that she sustained a facial artery blow out
in right cheek region.
• The skin and mucosa over right cheek became
necrotic and eventually an orocutaneous fistula
developed in the region over a period of time.
• She gave a history of limited mouth opening due to
contracture and scar at the right oral commissure.

30. The selected tissue expander was a rectangular
type of sialistic expander, of dimensions 61 mm
35 mm 32 mm, 50 ml in volume with a distant
filling valve where the injection port that
receives the needle during inflation is attached by
a stem to the expander

31. Step 1: Excision of fistulous tract along with primary closure and
placement of tissue expander.
Steps
A linear skin incision was placed parallel
to the lower border of mandible in the
submental region.

32. The tissue expander was placed
subplatysmally in created pocket in order
to create adequate tissue bulk for
reconstruction. Intraoperatively 30 ml of
saline was injected to inflate the tissue
expander in order to avoid any folding of
the expander within the tissue

33. Step 2: Postoperative periodic injection of
saline. Postoperatively periodic injection of 5
ml of saline into the injection port was done at
1st week review and then at 2 weeks interval.
The desired expansion period calculated was 9
weeks, when altogether 30 ml of saline had
been injected into the tissue expander

34. Step 3: Surgical management: scar tissue
excision and cheek reconstruction using
rotation advancement of expanded skin flap.

35. Prior to surgery the limits of the scar were marked as points and
the corresponding points on the expanded tissue were identified,
so that optimal reconstruction was possible

36. Intraoperatively the margins of the scar
tissue to be excised were marked

37. Scar tissue was excised , so as to leave the
underlying apparently healthy connective
tissue as a vascular bed

38. A linear incision parallel to the margin of
the tissue expander was made at the region
adjacent to the excised scar tissue to
remove the tissue expander and
consecutively the expanded flap was raised

39. The capsule formed around the expander
was retained within the flap so that
adequate bulk could be obtained to
compensate for the loss of bulk at the
recipient site

40. Scoring of the capsule was performed so
as to achieve proper mobilization of the
flap

41. Flap edges were sutured with 5- 0
polypropelene without tension at the
margins

42. Lateral view 1 month post op

43. Four months post op

44. Case Report -2

45. Case Report -3

46. Complications
• Hematoma
• Seroma
• Cellulitis and infection
• Migration of the expander.
• Infection, necessitating removal of the expander.
• Wound dehiscence.

47. • Necrosis over the fill port or over the expander.
• Implant exposure or extrusion
• Pain that may necessitate expander removal.
• Neurapraxia that may necessitate expander removal.
• Erosion or deformation of underlying bone.

48. Hematoma
 Bleeding into the newly dissected space is an iatrogenic issue.
Meticulous haemostasis at the time of expander insertion is
important.
 If an haematoma is detected as evidenced by excessive pain,
bogginess in the pocket and increased tissue tension, it is
immediately addressed by opening the pocket, draining the
haematoma, irrigating the pocket, confirming haemostasis,
replacing the expander and closing securely once again
followed by a course of 5-7 days of antibiotic coverage.
 Expansion can be started after 2-3 weeks once good healing of
the incision site is assured.

49. Seroma
 Rarely, they may be due to leakage of the
injected saline into the potential tissue space
between the expander and the overlying skin.
 If significant, they may require careful aspiration
(with risk of balloon puncture) or drainage.

50. Cellulitis
 Cellulitis of the overlying skin seen later
in the process is usually due to
contamination from folliculitis, stitch
abscesses, abscesses under scabs or due
to some lapse in strict asepsis during the
weekly inflation process.
 Cellulitis is treated on an emergent basis
by: (1) Stopping expansion temporarily,
(2) deflating the expander by 10% to
minimise any ischaemic compromise, (3)
instituting immediate antibiotic and anti-
inflammatory cover and (4) local
treatment with fomentation with
glycerine/magnesium sulphate.

51. DEFLATION OF THE BALLOON
 The most common cause for this in the past,
when implant ports/valve were incorporated on
the dome itself, was iatrogenic due to misdirected
needle pricks into the expander envelope itself.
This would obviously lead to puncture, leakage
and finally deflation, which was basically an
implant failure.

52. FLAP ISCHAEMIA AND SKIN
NECROSIS
 This is a dreaded complication because it directly affects the
tissue that is expected to be recruited by tissue expansion.
 Compromise of the vascularity and ischaemia in the flap is
usually due to pressure from the underlying inflating expander.

53. EXPOSURE OF THE EXPANDER
AND/OR VALVE
 The common reasons for this complication are: (1) breakdown of
the incision through which the expander was inserted, (2)
persistent implant folds causing erosion of the overlying skin and
(3) if and when the expander is inserted under unstable thin burnt
or scarred skin, under skin grafts or irradiated tissue.

55. BONE RESORPTION
 Pressure from the inflating balloon is often noted to cause bone
resorption and contour depressions

56. ENDOSCOPIC TISSUE
EXPANSION
Endoscopically assisted tissue expander placement was
first described by Serra et al in 1997
 The endoscopic approach allows placement of tissue
expanders through smaller, remote incisions.
Specialized endoscopic instruments allow improved
visualization of the tissue expander pocket through
smaller incisions.
Endoscopic Approach for Tissue Expansion for Different Cosmetic Lesions in
Pediatric Age.,. Annals of Pediatric Surgery Vol. 6, No 1, January 2010, PP 27-33

57. Advantages
• Incision can be placed at a distance from the tissueto be
expanded.
• Fewer incisions, reduced operative time, reduced
complication rates, less time to full expansion
• Decreased rate of wound dehiscence, a decreased rate
of tissue expander extrusion.
• More tissue expanders can be placed through a single
incision because of the improved visualization.

58. CONCLUSION
Tissue expansion is a vital and valuable tool in our reconstructive
armamentarium but one which requires a careful and correct patient selection,
meticulous planning and precise step-wise execution. Like all modalities of
reconstruction, there always lies the possibility of unfavourable results because
of the use of a prosthesis, the long duration of the entire process and several
ambiguous intrinsic and extrinsic factors related to the same. However as long
as one anticipates these sequelae and complications and is able to tackle them
satisfactorily, it remains one of the most exciting advancements in our field in
the last 50 years.

59. References
Tissue expanders in facial reconstructive surgery International Journal of Oral
& Maxillofacial Surgery Volume 36, Issue 11 , Page 1058, November 2007.
Tissue Expansion: A Valuable Adjunct to Reconstructive Surgery Ann. Pak. Inst.
Med. Sci. 2013; 9(3): 103-104
The effect of tissue expanders on the growing craniofacial skeleton, Indian J
Plast Surg January-June 2006 Vol 39 Issue 1
KanerD,Friedmann A.Soft tissue expansion withself filling osmotic tissue
expanders before vertical ridge augmentation J.ClinPeriodontol 2010;
Tissue regeneration during tissue expansion and choosing an expander Indian
Journal of Plastic Surgery January-April 2012 Vol 45 Issue 1
The Use of Self-Inflating Soft Tissue Expanders Prior to Bone Augmentation of
Atrophied Alveolar Ridges Mertens C, et al. Journal Clin Implant Dent Relat Res.
2013 May 28. doi: 10.1111/cid.12093
 Local Flaps in Facial Reconstruction,2nd Edition.,Shan.R.Baker.
 GRABB AND SMITH’S PLASTIC SURGERY, 6th edition ,Charles .H.Thorne.