PLASTIC_AND_RECONSTRUCTIVE_SURGERY_OF_H_N.doc

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PLASTIC_AND_RECONSTRUCTIVE_SURGERY_OF_H_N.doc

  1. 1. PLASTIC AND RECONSTRUCTIVE SURGERY OF THE HEAD & NECKGeneral considerationsPlastic and reconstructive surgery of the head and neck is the common term for thesurgical procedures and techinques that are dealing with the restoration, remodelingand repair of soft and bone tissues of the head and neck. The defect or disfigurementin the head and neck area may occur as a result of accidents, congenital anomalies,treatment for neoplastic diseases, burns or necrotizing infection. Reconstructiveplastic surgery is usually performed to improve function, but it may be done toapproximate a normal appearance as well. The surgical procedures that areperformed to improve cosmetics alone, or enhance the otherwise normal facialappearance toward some aesthetic ideal, are called cosmetic or aesthetic surgery.The same procedure may be used as the function improving surgery in one case andthe cosmetic surgery in other (for example :rhinoplasty of the croocked nose).There are mainly three types of procedures: reshaping (remodeling) procedures,restoring (reconstructive) procedures and corrections (secondary correctiveprocedures, scar revision). The procedure may involve only soft tissue surgery or thebone surgery as well.Remodeling procedures of the soft tissue include tissue reduction, tissuetransposition and the rearrangement of the adjacent tissues(for example:blepharoplasty, facial reanimation in facial palsy, a variety of local rotational andtranspositional flaps). Remodeling procedures of the facial bones include differentosteotomies and fixation in correct position (zygomatic bone osteotomy, Le Fortosteotomy, sagittal osteotomy, etc).Reconstructive procedures are performed to restore larger tissue defects, either softor bone. They are, as a rule, based on tissue transplantation: the tissue is raisedfrom the area (donor site) distant from the defect (recipient site). A tranferred tissueis usually called flap. Flaps are classified on the basis of their blood supply; there arethree main types: random-pattern, axial-pattern, and myocutaneous. Random-patternflaps rely on the dermal and subdermal plexus, whereas axial-pattern flaps receivetheir blood supply from named subcutaneous arteries and veins running superficial to
  2. 2. the underlying muscle. Myocutaneous flaps are designed around a segmental arteryand vein that run the length of the flap, sending perforating vessels through themuscle and up to the overlying skin. Most local facial flaps have a random-patternblood supply. A pedicle flap is tissue that is moved on a vascular pedicle which is notdivided form the origin vascularisation (pecoralis major flap supplied by the pectoralbranch of the thoracoacromial artery). If the pedicle flap is raised from the adjacentregion (upper thorax, shoulder) it called regional flap. If necessary, the pedicle maybe divided after 3-4 weeks.If the tissue graft is completely removed from its donor site with an artery and a veinand is connected to an artery and a vein at the recipient site by microvascularsuturing, it is called free flap.Microvascular free soft-tissue flap selection in head and neck reconstructionincludes: radial forearm flap, lateral thigh or anterolateral thigh flap, latissimus dorsiflap, gracilis flap.Free flaps should be distinguished from free skin grafts (split thickness –sec.Thiersch , full thickness- sec. Wolf) - skin slices which vascular support entirelyrely on recipient vascularisation.Nonvascularized bone grafts are often used for minor or medium bone defects,especially in the upper and middle face. Donor sites are : iliac crest, ribs, outer cortexof calvaria (parietal bone mostly). In these areas (midface, frontorbital region)aloplastic materials could be also convenient (titanuim mesh, polyurethan implants(medpore), goretex etc.). Larger maxillary and mandibular defects reqire "living"bone transplant – free vascularized bone usually taken from the fibula (supplied byfibular art. branch perforators) or iliac crest (deep circumflex iliac art. supply).Posttraumatic deformitiesThe best way to prevent post-traumatic facial deformities is to obtain the appropriatetreatment at the time of the injury. However, there are still patients that end up withsignificant deformities. These are patients that for whatever reason are treated
  3. 3. inadequately or because of life-threatening other injuries, do not receive anytreatment of their facial injuries.Unrepaired or inadequately reduced facial fractures can result in a wide range ofsevere cosmetic and functional deformities. Unrepaired fractures around the orbitscan cause a sunken-in appearance of the eyes, nasal deformities, as well asfunctional problems with vision (double vision). Unrepaired injuries of the middle andlower face can cause contour deformities, flattening of the cheeks, or malocclusion ofthe teeth with difficulty chewing. These are but a few of the many problemsassociated with post-traumatic facial deformities.Late repair or reconstruction after the soft tissue and bones have healed is muchmore difficult than repair at the time of initial injury. Reconstruction requires wideexposure which enables the surgeon to have direct visualization of the bonydeformities. Bone cuts are then made to reposition the displaced bone and reattachthe soft tissue back into its normal position. Missing or severely deformed bone mayrequire replacement with bone grafts.Basic rhinoplasty surgery involves the correction or reshaping of existing nasalstructures, whereas more extensive cases will require the tranposition of foreheadpedicle flap. Meticulous attention to detail when repairing or reconstructing the nasallining, skeletal support, or skin covering is essential to obtain a structure that is fullyfunctional as well as pleasing to the eye.When large defects of the nose and/or orbit are present from tumor resection ortrauma, flap tissue provides the best aesthetic coverage. The most common flapused for the reconstruction in this area is the forehead flap. This reliable flap cansupply a large area of skin with good color match making it suitable for partial or totalnasal reconstruction.Reconstruction of the nasal and orbital skeletal framework is frequently necessary inpatients with traumatic deformities. This support is best obtained using bone orcartilage. Outer table calvarial bone grafts harvested from the parietal area of theskull make excellent cantilever bone struts for support of the nasal dorsum. Thesegrafts can be rigidly fixed with lag screws to provide good stability and dorsal contour.
  4. 4. The midface posttraumatic deformities with or without malocclussion have similarfunctinal and aesthetic impairments as other midface deformtiies and are treated withthe same surgical procedures (Le Fort osteotomy, repositioning and fixation inproper position).Postraumatic deformities of the mandible may present with asimetry andmalocclussion requiring osteotomies, reshaping, and rigid fixation in a properposition. In cases of mandibular defect (gunshot injuries or missile wounds) the bonereconstruction is required.Cancer reconstructionSkin cancerRepair of small or medium facial cancer defects are usually close by adjacent skinflaps or skin grafts. Large facial cancers occasionally need to be repaired usingregional flaps or free tissue transfer(skin, muscle, and/or bone from a different part ofthe body brought to fill the facial defect).Oral cancerDisabilities resulting from tongue and mandibular resections include impaired speecharticulation, difficulty swallowing, deviation of the mandible during functionalmovements, poor control of salivary secretions, and often cosmetic disfigurement.Consequently, these patients seldom return to presurgical levels of social function.Advanced tumors of the anterior two thirds of the tongue and floor of the mouth oftenrequire extensive resection of bone and soft tissue. This loss of mobility combinedwith the loss of motor and sensory innervation leads to misarticulation of manyspeech sounds. Deglutition is less impaired, and most patients learn to swallow fairlyefficiently. Tongue function is less affected if the resected portion is restored witheither myocutaneous (pectoralis major) or free flaps. The myocutaneous flap restoresbulk, prevents deviation of the mandible, and permits the reconstructed tongue toarticulate more effectively with the palatal structures, but tongues reconstructed withfree flaps are less likely to become heavily scarred and immobile. If much of themandible is segmented and removed, the remaining functional mandibular segment
  5. 5. will be retruded and deviated towards the surgical side at the vertical dimension ofrest. When the jaw is opened this deviation increases. These factors, combined withimpaired tongue function, may prevent effective mastication. Resections of thetongue and mandible often obliterate portions of the lingual and buccal sulci so that ameans of collecting and channeling secretions posteriorly no longer exists. If themotor and sensory innervation of the lower lip on the resected side is lost, impairedspeech, eating, and control of saliva (drooling) occurs.When removal of tumors in the anterior floor of the mouth requires that the mandiblebe resected anteriorly, and when mandibular continuity is not restored, the tworemaining posterior fragments are pulled medially by the residual mylohoid musclesand superiorly by the muscles of mastication. Severe disfigurement and dysfunctionresult. Free flaps from the fibula can be used immediately to restore the lost hard andsoft tissues, and most patients emerge with excellent function and acceptableappearance.If the surgical wound is closed primarily (primary closure) by suturing the edges ofthe wound together, the functional disabilities are compounded. The introduction ofthe myocutaneous flap in the late 1970s ameliorated some of the disabilities, andimproved tongue mobility resulted in acceptable speech, swallowing and salivacontrol. The advantage of free-tissue transfers (free flaps) over musculocutaneousflaps is the improved blood supply, enhancing wound healing and flap survival. Thefibula is the preferred donor site if mandibular reconstruction is required. Theosteotomized fibula provides sufficient length and bulk and bone. Osseointegratedimplants can be placed to retain and support prosthesis.Vestibuloplasty and tongue release are of particular value when mandibularcontinuity has been maintained or restored. Prosthodontic restoration (partial orcomplete denture) improves food intake and speech but also the patient’sappearance providing the contour and support for the lower lip and cheek portions ofthe resected area.Free bone grafts. Reconstruction after extensive resection of oral malignancies withfree grafts is difficult because of the lack of sufficient soft tissue to receive the graft,the decreased vascularity of the tissue bed secondary to radiation therapy and/or
  6. 6. radical neck dissection, and the difficulty in achieving proper fixation of the graftduring the healing period. The primary goals are to restore facial form, mandibularcontinuity and, in selected patients, appropriate volume and quality of bone should beprovided for the placement of osseointegrated implants.Autogenous graft sources for resected bone include iliac crest, rib, and clavicle. Theuse of myocutaneous flaps for closure of the initial wound facilitates free-bonegrafting of continuity defects by enhancing the volume and vascularity of the recipientsoft tissue.A major advance in mandibular reconstruction has been the development ofimproved techniques in microvascular surgery, which allow for composite grafting oflarge volumes of tissue. In microvascular surgery, which allow for composite graftingof large volumes of tissue. In microvascular free-tissue transfer (free flaps), bone,muscle, connective tissue, and skin can be autogenously grafted and remain viable.The grafting can be accomplished simultaneously with resection of the tumor, withexcellent results.Numerous donor sites have been used. The radial forearm is favored forreconstruction of most extensive soft-tissue defects such as the tonsillar, partial-glossectomy, and floor-of-mouth defects. The composite fibula flap is the preffereddonor site for most complex oro-facial-mandibular defects. Multiple osteotomies maybe performed without devascularizing the bone segments to replicate the contour ofthe replaced mandible. Fibular thickness makes it an excellent recipient ofosseointegrated implants.

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