Presentation on theme: "Section 21 SURGERY Grafts 148 By yalda attarzade."— Presentation transcript:
Section 21 SURGERY Grafts 148 By yalda attarzade
Free skin grafts are pieces of skin that have been severed from their local blood supply and transferred to another location divided into four types: full-thickness skin grafts (FTSGs), splitthickness skin grafts (STSGs), composite grafts, and free cartilage Grafts FTSGs : are composed of the entire epidermis and the full thickness of dermis, including adnexal structures such as hair follicles and sweat glands. STSGs ” are composedof the full thickness of the epidermis and partial thickness of dermis. Composite grafts Are composed of at least two different tissue types, usually skin and cartilage. Free cartilage grafts consist of cartilage with its overlying perichondrium.
WOUND HEALING CONSIDERATIONS The first 24-hour:plasmatic imbibition, during which fibrin glue attaches the graft to its recipient bed wound exudate and to become edematous, gaining up to 40% in weight12. The graft thereby remains hydrated and obtains a supply of nutrients The fibrin beneath the graft is subsequently replaced by granulation tissue within hours:Anastomoses begin to formbetween the recipient bed and pre-existing vessels in the dermis of the graft, a process known as inosculation Vascular proliferation occurs next, with sprouting and budding of vessels in the graft and in the recipient bed bridging phenomenon,vascular connections arising from the recipient bed allow blood flow tooccur through pre-existing graft vasculature, sobridging phenomenon,vascular connections arising from the recipient bed allow blood flow tooccur through pre-existing graft vasculature, so
bridging phenomenon: vascular connections arising from the recipient bed allow blood flow to occur through pre-existing graft vasculature. Full circulation is restored to the graft within 4--7 days Restoration of the lymphatic circulation parallels restoration of the blood supply over the first week Epidermal proliferation : the 4th and 8th day post- transplant and persists for several weeks sebaceous and eccrine glands: degeneration and then partial regeneration Graft reinnervation: return of sensory nerve function may begin as early as 2-4 weeks after grafting, although patients do not usually regain full sensation for many months
extension of the ischemic period decreased graft survival Hematoma or seroma formation, infection, or mechanical shear forces may disrupt the fragile vascular connections between the graft and its recipient bed. after the ischemic period :smoking, diabetes mellitus, protein deprivation, and severe trace element or vitamin deficiencies may also increase the risk of graft failure Medications:corticosteroids, chemotherapeutic agents, other immunosuppressive drugs, and anticoagulants,may interfere with wound healing as well. Other causes of graft failure : insufficient vascularity due to necrotic debris within the recipient bed, hematoma, seroma, an avascular wound bed, infection, excessive graft tension, mechanical shearing forces, and improper postoperative care common infectious agents associated with graft failure:coagulase- positive staphylococci, ~-hemolytic streptococci and Pseudomonas.(common in auricular grafts.) thorough preoperative evaluation,meticulous intraoperative technique, and good postoperativecare are essential maximize graft survival
FULL-THICKNESS SKIN GRAFTS
Ind ication s/Contra ind ication s most commonly used to repair facial defects resulting from the removal of skin cancers recipient bed must have a sufficiently rich vascular supply to promote capillary regrowth, as well as fibroblasts to supply collagen for graft adherence. Small avascular areas due to the bridging phenomenon. Larger areas of avascular tissue:patches of exposed bone, cartilage, tendon or nerve devoid of periosteum, perichondrium, peritenon or perineurium, respectively, are unable to support full- thickness grafts FTSGs can provide excellent color,texture and thickness matches for facial defects Wound contraction is minimized FTSGs is useful for defects of the nasal tip, dorsum, ala and lateral sidewall, as well as the lower eyelid and ear
Preoperative History and Donor Site Considerations preoperative evaluation: bleeding tendencies, alcohol use, use of anticoagulant medications(including aspirin and non-steroidal anti-inflammatory drugs) history of hypertension, Diabetes mellitus, nutritional deficiencies cigarette smoking immunosuppressive medications Selection of a donor site depends upon; the color, texture, thickness, and sebaceous qualities of the skinsurrounding the defect sun-exposed areas above the shoulders for the facial defects thinnest grafts: usually harvested from the upper eyelid or the postauricular sulcus. Medium-thickness grafts :often harvested from the preauricular and cervical regions, Thickest grafts:from the supraclavicular or clavicular region or the nasolabial fold Donor site will vary from one patient to another, upper eyelid skin may be used to repair lower eyelid defects, providing a good color and texture match in addition to a well-camouflaged donor site scar. Grafts used for lower eyelid defects should be oversized by % to to avoid the possible side effect of ectropion
Postauricular skin be useful as a primary donor site for eyelid defects (including those of the medial canthus), as well as for auricular defects. postauricular skin is relatively non-sun-exposed, may not provide a good color or texture match for facial defects Preauricular skin can be used to repair most nasal defects, The donor site scar in this region can be easily camouflaged Hair-bearing skin from the temporoparietal region may be used to repair defects of the eyebrow Skin from the nasolabial fold or from the conchal bowl can sometimes be used to graft small nasal tip defects in other areasFor larger defects of sun-damaged skin, such as the forehead and scalp vertex:, the supraclavicular region or lateral neck can be used as a donor site areas below the neck with thin, redundant skin, such as the upper inner arms, forearms and inguinal area, can be used
Description of Technique In. order to perform an FTSG, a template of the defect is first made, The graft should be 3-5% larger in size than the true template For eyelid defects, grafts should be oversized significantly Marking the donor site must be prior to local anesthesia Epinephrine may be used without compromising graft survival antibacterial preparation such as chlorhexidine,rinsed with saline, and draped with sterile towels. The donor site is excised with a scalpel to the level of the subcutaneous fat graft is placed in normal saline, where it may remain for up to 1-2 hours. Grafts may be utilized up to 24 hours after harvesting if refrigerated or kept on ice. defatting of the graft If indicated, part of the dermis can also be trimmed Contouring of donor skin in FTSGs may be challenging,
Securing the Graft Perimeter sutures, basting sutures, support dressings, or a combination of any or all of these can be used to anchor the FTSG four to eight interrupted 5-0 or 6-0 absorbable ornon-absorbable sutures may be placed at opposite edges of the graft periphery (e.g. at 3,6,9 and 12 o'clock) running suture is placed in almost epicuticular fashion, passing the needle first through the graft and then through the surrounding skin.slightly higher in the dermis on the graft side and slightly deeper in the dermis of the surrounding skin tissue adhesives Basting sutures:simple interrupted 6-0 fast-absorbing gut suture, can be placed in the central portion of the graft. pressure dressings:Immobilization of the graft over its bed can be maximized by the use of pressure dressings.
Postoperative Care After the pressure dressings are removed, gently clean the donor site and area immediately surrounding the bolster with hydrogen peroxide followed by application of antibiotic or petrolatum ointment twice a day. dressing remove in 1 week, the bolster and all tic-over sutures are remove and thenSteri-strips may be applied to the donor site as need. The color of the graft may range, however, from pink or red to darker blue or purple, depending on the extent of graft revascularization. A bluish tinge may be a sign of ecchymosis rather than graft failure. A black graft signals necrosis and is undesirable.
the entire epidermal surface may become black and necrotic, and then slough without adversely affecting the dermal portion of the graft, eschars should not be debrided, since they can serve as natural dressings, After sutures are removed, gentle cleansing with hydrogen peroxide to remove all crusts is recommended, followed by a thin layer of or antibiotic ointment. direct shower water to the area, and excessive activity should be avoided for an additional 1 to 2 weeks.
Variations/Unusual Situations The purse-string suture is a subcuticular stitch that is placed around the periphery of a circular or oval surgical defect allows partial closure of the defect by advancing skin from the entire periphery of the wound, help to cover areas of exposed cartilage or bone at the edge of the wound that could inhibit graft take . FTSG placement decreases the risk of significant wound contraction,
Burow's grafts Defects of the nasal sidewall and dorsum, and sometimes of the forehead,lateral neck or other areas, may be repaired with Burow's grafts Burow's grafts utilize skin adjacent to the defect superior to the defect if on the nose, and medial or lateral to the defect if on the forehead. The Burow's triangle is excised and the resulting donor defect is closed primarily, thereby partially decreasing the size of the original defect. The triangle is defatted, trimmed, and sutured into the defect.
Deep nasal defects Delaying FTSG placement : for 12 to 14 days may increase the likelihood of graft survival over defects of the nasal tip and ala with denuded cartilage in depressed defect on the nose that immediate reconstruction is preferred, dermal grafts can be used as a tissue filler prior to FTSG placement effectively fill the defect, little risk of resorption, eliminate the need for a more complicated choice of repair drumhead' graft repair: 1 application of an overlying rigid plastic suspension coupled with an undersized graft, 2 preventing graft depression and nasal valve collapse
Perichondrial cutaneous grafts (PCCGs) are actually composite grafts composed of full- thickness skin and subjacent perichondrium Use in defects with exposed Cartilage harvested from the conchal bowl, The cartilage is not removed, making this graft more analogous to a FTSG advantages of PCCGs over FTSGs are thicker, have a greater chance of survival under conditions of vascular compromise, contract less than FTSGs.
Postoperative Complications short term problems of graft failure:infection, hematoma, seroma,and shearing forces of the graft over the wound bed Infection after grafting of facial defects, in particular, is not often encountered,and oral antibiotics are not routinely give postoperatively. be gentle while handling tissue intraoperatively, and to minimize devitalized tissue created by electrocautery, to minimize the risk of infection. Prophylactic oral antibiotics that cover Staphylococcus and Streptococcus species in selected patients,especially those with diabetes mellitus, immunosuppression, or a prolonged intraoperative time Hematoma and seroma formation can be avoided by meticulous hemostasis intraoperatively, pressure dressings, and postoperative caution
patients may be instructed to avoid aspirin for 10 days before surgery, non-steroidal anti- inflammatory drugs for 5 days before surgery, and alcohol for 2 days before and 2 days after surgery. Warfarin can often be discontinued 2 days before surgery and resumed the day after based on the recommendations of the patient's internist or cardiologist. not to engage in vigorous activity, heavy lifting or bending for at least 1-2 weeks after surgery.
Long-term complications of FTSGs consist of cosmetic and functionalproblems FTSGs usually take months to look natural Make-up :can be use 3-4 weeks after graft placement. FTSGs are often depressed during their first 2-4 weeks. This depression will usually correct itself within 4-6 weeks. careful donor site selection will minimize the color, texture and contour deformities Spot dermabrasion or laser resurfacing : after 6 weeks to 6 months improve elevation and color and texture mismatch.
Hyperpigmentation can be treated with a brief course of topical hydroquinone and/or tretinoin. The use of tretinoin pre- and postoperatively has not beenshown to alter the course of healing of FTSGs wound contraction: centripetal movement movement of unopposed elastic fibers, variable amount of shrinkage depending upon the thickness and elasticity of the donor site 38% by 16 weeks after placement Grafts of periorbital area and nose contracting more than those applied to the scalp and temples contraction are usually minimal in FTSGs. If wound contraction does result, secondary revisional surgery may be needed..
SPLIT-THICKNESS SKIN GRAFTS
Split-thickness skin grafts (STSGs) consist of epidermis and a portion of the dermis. These grafts vary in thickness from approximately thin ( inches/ mml, medium ( inches/ mml thick ( inches/ mm!,
Indications/Contraindications likely to survive when placed on almost any recipient bed, including those with a limited vascular supply like periosteum, perichondrium, peritenon and perineurium large defects, particularly those that cannot be covered by a flap or would heal too slowly by secondary intention, as well as refractory venous leg ulcers surgical defects in sites at high risk for tumor recurrence, Advantages of STSGs over FTSGs improved chance of survival under conditions of vascular compromise ease of application ability to cover large defects, ability to act as a 'window' for recurrence of high-risk lesions Disadvantages of STSGs suboptimal cosmetic appearance, the presence of a granulating donor site wound requiring postoperative care greater graft contractionless less durable than FTSGs, poor color and texture match with the surrounding skin
Preoperative History and Donor Site considration STSGs should be harvested from an area from which a broad area of skin can be removed while still concealed beneath clothing. most common donor sites: anterior, medial and lateral portions of the upper thigh, the inner and outer aspects of the upper arm, and the inner aspect of the forearm. Instruments: Power-driven derma tomes and large freehand knives require large flat donor surfaces,(thighs, abdomen and buttocks) freehand or with a Davol-Simon dermatome:for smallest graft
Description of Grafting Techniques instruments used to harvest STSGs can be classified into freehand and electric dermatomes. Freehand dermatomes include scalpel blades, double-edged razor blades, and knives such as the Week blade.(considerable technical expertise is required) A standard # 15 or # 15c blade can be an effective tool for harvestingsmall STSGs of medium thickness. 1-the donor site is marked out 2- anesthetized. 3-The donor site is scored lightly with the blade, 4- the graft is harvested by orienting the and gently sweeping the blade just below the level of theblade parallel to the skin epidermis, so that the blade is just visible beneath the skin assistant apply traction to the donor site while the graft is harvested. Several blades may be required to harvest the graft, as the sharpness of the blade diminishes quickly with multiple passes. This technique may be especially useful in harvesting small STSGs of medium thickness for the repair of auricular and postauricular defects.
Power-driven dermatomes standard method of harvesting larger STSGs STSGs can be obtained easily and reliably with any of these devices After the dermatome is prepared, the donor and recipient sites are anesthetized with lidocaine with or without epinephrine, and the areas are prepped and draped The donor site is lubricated to ease travel of the dermatome over the skin handpiece is held on the donor site at an angle of 30-45°. A throttle control is pressed to start the cut, and the unit is guided forward using light downward pressure to ensure that the cutting edge remains in continuous contact with the donor site. An assistant applies tension by pulling the skin away from the donor area to create a flat, even surface. After the graft has been harvested, the graft is placed in sterile saline
Securing the Graft STSGs should be secured so that infection, hematoma or seroma formation, and mechanical shearing forces can be prevented perimeter and the central portion of the graft must be secured The edges of STSGs need not be as closely approximated to the surrounding wound edge as those of FTSGs, the perimeter of the graft may be secured with sutures or staples. Several centrally placed basting sutures may also be helpful a non-adhesive dressing or pressure dressing may be applied as an additional precaution. Sutures or staplesare removed after 7-10 days
Donor Site Care the donor defect, often causes more postoperative discomfort than the grafted area itself. This partial-thickness wound heals by secondary intention. bulky occlusive dressings left in place for days,(Opsite) This dressings allow the serosanguineous drainage,keeping the wound moist and thereby shortening healing time.
Variations/Unusual Situations Meshing the graft with scalpel slits: allow for drainage of accumulated blood or serosanguineous material that could otherwise inhibit graft-bed contact used to expand the surface area of an STSG may be utilized to expand the surface area of the graft by a ratio ranging from3: I to 9: I. provide coverage of a large recipient area with smaller donor grafts
Postoperative Care During the first 24 hours after grafting, a large amount of serosanguineous fluid may accumulate beneath the donor site dressing the fluid can be drained with a needle and syringe, and an patch applied. Depending on the thickness of the STSG, the donor site should fully re-epithelialize in 7-21 days. The flat scar usually evolves in color from pink to white over a period of months.
coplications early complications : stem from failure of engraftment,may result from hematoma or seroma formation, infection, and shearing forces. Late complications: divided into cosmetic and functional problems. Color and texture mismatch with surrounding skin Grafts often remain erythematous for months to years after placement exhibit significant hyperpigmentation and hypopigmentation Darker-skinned patients are especially prone to graft hyperpigmentation, Patients should minimize to avoid hyperpigmentation :graft exposure to the sun without sunscreens for 6 months, and wear sunscreens consistently thereafter xerosis and a build-up of keratinous debrisand then scaling, pruritus and dryness can be minimized with the liberal use of emollients
STSGs contract more than FTSGs produce joint contraction if placed over or near joints Contraction facial grafts, near the nasal ala retraction of the nasal ala the eyelid,, ectropion the helical rim distortion of the helical rim and the free margins of the vermilion border, distortion of the vermilion border, Hypertrophic scarring of the graft and donor sites :can be treated with corticosteroid-impregnated tape or intralesional steroids. Graft fragility and breakdown :in areas of trauma such as the lower leg or in areas with little underlying soft tissue support, such as those directly overlying perichondrium or periosteum bullae can occur within graft sites
COMPOSITE GRAFTS CG consisting of two or more tissue layers. In dermatologic surgery, these grafts are usually composed of skin and cartilage, CG Useful for the repair of full-thickness alar rim defects, as well as nasal tip defects with cartilage loss Full-thickness nasal mucosal defects can be repaired using composite grafts to provide mucosal lining and structural support, and a nasolabial or forehead flap can be moved into place thereafter to reconstruct the overlying soft tissue defecet
Preoperative History and Considerations Composite grafts require rapid revascularization graft circulation occurs via direct vessel anastomoses between the subdermal plexus of the graft and the subdermal plexus of the wound edge(bridging phenomenon) CG must be limited in size, with no point being more than 1 cm from a vascular source, as the risk of central necrosis increases significantly at graft diameters greater than 2 cm Composite grafts for nasal alar and ear reconstruction are possible CG pass through four stages: 1 -the tissue blanches completely. 2- By 6 hours, the graft develops a pale pink color, signifying anastomosis of the vessels of the graft with those of the recipient site. 3- At hours, the graft appears dusky blue, reflecting venous congestion, 4- by 3-7 days, it should be pink, indicating graft survival.
Donor Site Considerations for Composite Grafts CG provide an excellent cosmetic and hmctional alternative for repair of small full-thickness defects of the alar rim less than 2 cm in diameter. CG taken from the earlobe can be used for this type of repair CG taken from the cartilaginous portion of the ear are more frequently used Doner sites :crus of the helix, the helical rim and the conchalbowl Small alar defects involving loss of cartilage can be repaired using the helical crus as the donor site more substantial defects repaired using the helical rim or conchal bowl. Donor defects of crus of the helix can be repaired with minimal scar formation, to repair helical rim donor sites :wedge excisions are usually necessary to repair The conchal bowl donor site heals by secondary intention.
Advantages of auricular CG in the repair of full thickness defects of the alar rim to the 1-presence of cartilage, which 2- provides structural support and stability, with prevention of alar distortion during inspiration and at rest Disadvantages of composite graft 1- Higher risk of graft failure with an increased number of tissue layers 2- graft size limitations, 3-limited donor tissue availability. CG for full-thickness nasal mucosal repair: triangular fossa, scapha, conchal cavum,cymba or helical crus of the ear.
Description of Technique The donor and recipient sites are anesthetized And cleaned If the alar tissue is scarred and retracted, this area must be vigorously debrided to assure the best possible blood supply The defect is measured and a template made tongue-in-groove technique maximize graft stability and increase graft survival Two cartilaginous wings are marked out and anesthetized on either side of the donor site prior to graft harvesting. the skin overlying these two cartilaginous wings is removed, leaving the cartilage with its overlying perichondrium These wings are then inserted into pockets prepared within the alar tissue of both sides of the defect (interlocks) Interlocking the graft minimize shearing forces and provide a larger surface area for revascularization.
The graft is sutured into place in two layers. 1-The undersurface of the graft, the inner lining of the nose(6-0 absorbable suture). 2- The skin is then closed (6-0 nonabsorbable suture) The needle should pass through the mucosal portion of the graft first, then through the outer epithelial edge of the graft, so that the knots are tied external to the graft, The cartilage does not need to be sutured A Vaseline gauze or Xeroform dressing for the nasal vestibule for support antibiotic ointment for the external suture line. Conchal bowl composite grafts 1-used for reconstruction of deep defects on the nasal ala 2- are harvested in essentially the same way asthe helical crus the helical crus 3-advantages :increased bulk, excellent cosmetic match for the missing sebaceous skin of the nose.
Donor Site Closure Helical crus often be closed in a side-to-side fashion. simple advancement, rotation or transposition flap may also be utilized to take advantage of loose preauricular skin. Helical rim defects are usually closed with an ear wedge resection. triangular fossa, scapha, conchal bowl or cymba heal well by Secondary intention
Variations/Unusual Situations Delayed intranasal knot tying facilitate wound closure by improving visualization, allowing for gentle manipulation of tissue, and enabling precise placement of sutures in a confined space 6-0 fast absorbing chromic gut is first passed through the nasal mucosa, and then passed through the corresponding location on the 'mucosal' side of the graft
Postoperative Care Ice packs Oral antibiotics are generally advisable because of the high bacterial colonization around the nares and them higher risk of failure with composite grafts. Sutures are removed after 1 week
Complications early stages :necrosis of healing Late complications :contraction, textural changes, atrophy, and contour,irregularities If the cosmetic result is suboptimal, dermabrasion or laser resurfacing may be performed 6 weeks to 6 months postoperatively In the event of composite graft failure:1- two- stage revision with placement of a cheek interpolation flap 2- alternatively, a second composite grafting procedure
Conchal bowl donor sites 1-greater risk of postoperative bleeding 2-infection with Pseudomonas (Cleaning the ear with a dilute solution of vinegar, applying topical gentamicin ointment, and the use of oral quinolone antibiotics prophylactic measures If infection is suspected, oral quinolone antibiotics should be started immediately, and therapy should be guided thereafter by the results of cultures and sensitivities. If the infection does not resolve with appropriate antibiotics, the presence of a fungal infection, most often secondary to Candida, should be excluded.
FREE CARTILAGE GRAFTS Free cartilage grafts: are used most commonly in dermatologic surgery:for nasal ala, tip and sidewall, the ear, and the eyelid to restore the architecture of an anatomic site with significant cartilage loss in maintaining the position and contour of free margins against the forces of contraction during wound healing.
Nasal Ala The grafted cartilage provides a rigid but flexible cartilaginous framework that braces the alar rim against collapse during inspiration and expiration. FCG may be used in conjunction with flaps( like FTSGs ) to maintain airway patency and to minimize the risk of alar retraction during wound healing. It is possible that long-term survival of the cartilage itself may not ultimately be important, as the mere presence of the rigid framework of the graft in the initial stages of wound healing seems to be sufficient to inhibit alar retraction.
Nasal Sidewall and Tip and ear Deep defects of the nasal sidewall may lead to 1-loss of the upper lateral nasal cartilage. And Nasal valve obstruction scar contracture may lead to collapses the remaining cartilaginous structure of the nasal sidewall. loss of cartilage at the distal nasal tip necessitates replacement of structural support for optimal functional and cosmetic results Auricular defects involving loss of cartilage are generally repaired for cosmetic, rather than functional, reasons FCG may be used as braces along the helical rim to minimize the risk of contracture, and be used in the conchal bowl to assist in hearing aid placemene..
Preoperative History and Donor Site considrations Potential donor sites :conchal bowl(frequently used by dermatologic surgeons), auricular helix, the antihelix, nasal septum, and ribs Conchal cartilage is elastic, has a high degree of memory, has varied contours that can be matched to the contour of the ala. the posterior approach to the conchal bowl results in better camouflage of the donor site scar and preservation of the shape ofthe ear antihelix as a donor site, it is recommended that a subtotal resection be performed, leaving a complete rim of intact cartilage to prevent distortion
Description of Technique Nasal ala alar batten: provides a rigid but flexible cartilaginous framework to brace the alar rim against collapse. 1- The lengthof the cartilage graft is determined by and adding to that measurement an extra 4-5 mm. 2-conchal bowl donor site is incised anteriorly or posteriorly. 3-The skin overlying the cartilage is undermined with blunt scissor dissection to expose the perichondrial surface. 4-The desired length of cartilage is incised with the scalpel and a second incision is then made exactly parallel to the first, to create a cartilaginous strip that is 3-6 mm in width, depending upon the desired width of the graft. (a larger disk- or oblong-shaped piece may be harvested to match the base of the defect precisely.) graft is placed in sterile saline while the donor site is reapproximated with non-absorbable sutures.
Cartilaginous strip:1- the soft tissue of the recipient bed is undermined medially and laterally,2- and the ends of the graft inserted into the undermined pockets (interlocks) graft is sutured into its recipient bed with one or two 5-0 absorbable sutures After the graft has been anchored, a nasolabial flap or FTSG is sutured into place to complete the closure A standard tie-over bolster is placed over the FTSG and secured into place with 5-0 non-absorbable sutures. Sutures are removed in 1 week.
Nasal sidewall and tip Nasal sidewall grafts tend to be wider and broader than alar grafts multiple cartilaginous strips can be placed in perpendicular orientation to the lateral nasal sidewall a flap or FTSG may be performed to cover the remaining cutaneous defect. Nasal tip grafts for distal nasal reconstruction provide both proximal and distal structural support, thus optimizing the aesthetic and functional result The proximal grafts consist of bilateral batten grafts secured into place at the sites of the lateral cartilages with 5-0 or 6-0 non-absorbable sutures.
A columellar strut of cartilage often provides distal support, on top of which may be sewn an additional tip graft. Alar batten grafts secured to the columellar strut and lateral alar soft tissue provide alar rim suppor Paramedian forehead flap or melolabial interpolation flap may be placed thereafter to provide coverage of the cutaneous defect.
Ear large helical defect : the cartilage graft should match the defect as closely as possible in size and shape a narrow strip of cartilage matching the helical defect alone will result in helical rim collapse under the forces of woundcontraction. partial wedge closure of the defect performed decrease the defect requiring replacement of structural support. The cartilage graft is secured by sewing it to the intact cartilaginous framework with 6-0 absorbable or non- absorbable sutures. covered with a pedicled retroauricular advancement flap.
Eyelid Partial-thickness lower eyelid defects with loss of the tarsal plate: may be repaired with cartilage grafts. eyelid free cartilage grafts 1- provides structural support, 2-minimizing the risk of ectropion 3-preventing desiccation of the cornea.
Postoperative Care 1- minimize movement of the cartilage graft. 2-Routine wound care is performed to the flap or graft overlying the free cartilage graft. 3-Trauma to the area should be minimized.
Complications Postoperative complications: postoperative infection at the conchal bowl donor site(Gram-negative bacilli) bacterial and fungal cultures Empiric therapy with quinolone antibiotics prophylactic antibiotics and appropriate operative technique are used, the risk of suppurative chondritis is extremely lows inflammatory chondritis or perichondritis: Postoperative tenderness, swelling and erythema treated with cool compresses and non-steroidal anti- inflammatory drugs for several weeks or even months postoperatively. Later complications 1-resorption of the graft,2- displacement or deformation after placement,3- and extrusion. Treathment: Surgical revision
Future Trends autologous cartilage is the optimal grafting Other implantable materials for nasal reconstruction has been investigated, including porous, high- density polyethylene implants polyethylene implants :the ability to heal by secondary intention and support skin grafts when used to reconstruct auricular cartilage in rabbits They also well tolerated as replacements for native cartilage in patients requiring rhinoplasty or nasal reconstruction Tissue engineering generate autologous cartilage implants to fill defects of the nose or outer ear