Applied Anatomic Study On The Plasty Of Face

Part One Applied anatomy of the hierarchical structures of facial soft-tissueObjective To observe the hierarchical structures of facial soft-tissue, to furtherclarify the characteristic of facial soft-tissue, and to provide guides for clinicalapplication on the plasty of face.Methods Four fresh and eight formalin-fixed cadaver heads were dissected. Allof them had no destroy and injury. The incisal opening: was from vertex cranil topreauricula, cervical part alone coronal plane in the frontal region and middle face;from anterior to posterior alone middle line in the temporal region. The soft-tissuewas studied through an operating microscope, with hierarchical structures of facialsoft-tissue observed, relevant measurements recorded and photographs taken.Results1. In the midface, the soft-tissue is accordingly arranged into six layers: skin,subcutaneous fat, SMAS-superficial mimetic muscles, sub-SMAS fat tissue,parotidomassteric fascia and the deep mimetic muscles.①The superficial musculoaponeurotic system (SMAS) is a distinct tissue layerlying between the two layers of subcutaneous tissue and parotidomasseteric fascia,composed of muscular fibers and fascia. The inferior muscular portion is continuouswith the platysma, extending forward over the parotid and masseter to fuse with the investing fascia of the zygomaticus major; the superior fascial portion is in continuitywith the superficial temporal fascia.②There is a layer of fat tissue over the parotidand masseter. The fat tissue is a little more abundant near the zygomatic arch, andextends upward to the temporal region.③The parotidomasseteric fascia is incontinuity with the deep cervical fascia, extends forward into the facial deep fascia.The parotidomasseteric fascia is thinner above the parotid while thicher above themasseter.④The mimetic muscles are separated into two layers by the deep facialfascia in the mimetic muscle space. The superficial muscles include of the greaterzygomatic muscle, the levator muscles of the upper lip, depressor anguli oris muscleand depressor muscle of lower lip, et al. The deep muscles include of the levatormuscle of angle of mouth, buccinator muscle and mental muscle.⑤Thezygomatical ligaments, masseteric-cutaneous ligaments, mandibular ligaments andmandible angle ligaments et al fix the skin to deep tissues.⑥The branches of thefacial nerve pass through the fatty tissue within the mimetic muscle space to supplythe superficial and deep muscles. The branches of the facial nerve, transverse facialartery, the parotid duct and the facial vessels are contained in the space between theparotidomasseteric fascia and the deep facial fascia.2. In the frontal region, the soft-tissue is accordingly arranged into five layers:skin, subcutaneous fat, the frontal muscle, sub-aponeurotic soft tissue, and theperiosteum. The frontal muscle coheres to the skin and subcutaneous tissue. Thefrontal muscle and sub-aponeurotic soft tissue in the frontal region are continuouswith superficial temporal fascia and the loose areolar tissue respectively, while theperiosteum of frontal bone ends along the superior temporal line where the deeptemporal fascia originates.3. In the temporal region, layers of soft-tissue over the temporalis are skin,subcutaneous fat, superficial temporal fascia, areolar tissue, superficial layer of deep temporal fascia, superficial temporal fat pad, deep layer of the deep temporal fascia.①Adering to the skin and subcutaneous tissue, the superficial temporal fascia iscontinuous with the SMAS. An avascular layer of loose areolar tissue lies beneaththe superficial temporal fascia, with fat tissue being present near the zygomatic arch,which is in continuity with the sub-SMAS fat. The temporal branch of the facialnerve runs within the areolar tissue immediately beneath the superficial temporalfascia.②The deep temporal fascia is in intimate contact with the temporalis,splitting into two sheets of fascia at about 1 cm above the superior orbital rim. Thesuperficial layer attaches to the superior margin of the zygomatic arch, the deep oneto the posterosuperior margin. The superficial temporal fat pad is enveloped by thetwo layers of deep temporal fasica, within which the middle temporal artery and veinas well as zygomaticotemporal nerve pass through the fatty tissue.③The temporalextension of buccal fat pad lies beneath the deep layer of deep temporal fascia.④Over the zygomatic arch, the loose areolar tissue fuses with both the superficialtemporal fascia and the periosteum-deep temporal fascia, wherein the temporalbranches of facial nerve go through..4. The soft-tissue of cervical, facial, temporal and frontal region is continuouslayers. The platysma, SMAS, superficial temporal fascia and frontalis are in the sameplane, as are the fat tissue deep to ptatysma-SMAS and the loose areolar tissue deepto the superficial temporal fascia-frontalis. The superficial layer of deep temporalfascia, parotidomasseteric fascia-deep facial fascia, superficial temporal fascia andperiosteum of the frontal bone are also in continuity.Conclusions1.The SMAS is a distinct tissue layer lying between the subcutaneous tissue andthe parotidomasseteric fascia. It is in direct continuity with the platysma, extendingforward to connect the zygomatic major, running upward to be continuous with the superficial temporal fascia, as well as the frontalis and the orbicularis oculi. Neitherdoes the SMAS cover the mimetic muscles, nor spread to the nasolabial fold.2. SMAS is a landmark of fascia layer. The sub-SMAS fat tissue lying betweenthe SMAS and the parotidomasseteric fascia is the safe plane for surgical dissection.However, sub-SMAS dissection can not reach the nasolabial fold unless thedissection plane is converted to the subcutaneous tissue along the lateral border of thezygomaticus major. It is hard to keep integrality of the SMAS in operation, as thefascial portion of SMAS is weaker.3. In the sub-SMAS rhytidectomy, the sub-SMAS fat tissue lying between theSMAS and the parotidomasseteric fascia is the safe plane for surgical dissection inthe parotid region, while it must dissect carefully in order to avoid injury the facialnerve in the masseter region. As the SMAS extends forward to connect the greaterzygomatic muscle, so the dissection beneath SMAS can only reach the border of thegreater zygomatic muscle.4. The retaining ligaments are the fabric constitution containing fatty tissue.They distribute the definite layers of face, fix facial tissues and retain anatomic formof face. They are the anatomic markers in the facial surgery.5. The frontal muscle fiber connects the orbicularis muscle straightly in theeyebrow region. There is a layer of loose connective tissue between the frontalmuscle and periosteum, so are the orbicularis muscle and the orbital septum.Therefore, the frontal muscle and the orbicularis muscle can move upper and down.The frontal muscle movement can cause the orbicularis muscle movement.6. Over the zygomatic arch, the loose areolar tissue fuses with both thesuperficial temporal fascia and the periosteum-deep temporal fascia, wherein thetemporal branches of facial nerve go upward beneath the superficial temporalfascia. In the superior part of temporal region, the superficial temporal fascia adheres to the skin and subcutaneous tissue tightly, but adheres to the deeper areolar tissueloosely. The temporal branches of facial nerve go beneath the superficial temporalfascia closely, so the superficial plane of the deep temporal fascia is the safe plane forsurgical dissection.Part Two Applied anatomy of the facial blood supplyObjective To observe the origin, caliber, course, anastomosis, distribution ofthe facial vessels. To further clarify the distribution pattern of facial vessels, theprinciple of skin flap and its clinic significance.Methods Four fresh and twelve formalin-fixed cadaver heads were dissected.All of them had no destroy and injury.1. Macro-micro-dissection: The vessels of the face were studied under operatingmicroscope. The origin, caliber, course, anastomosis, distribution were observed. 2.Vessel casting: Three fresh adult head specimens were injected red perchloroethyleneat both common carotid arteries, then they were made into head specimens withvessel casting mould after the soft tissues were corroded. 3. Lead oxide-gelatininjection technique and three-dimensional reconstruction: A fresh female adultspecimen was injected lead oxide-gelatin at femoral artery. 24 hours later, thespecimen was scanned by CT, and then the soft tissue of face was taken from the body.The soft tissue of face was rescanned by CT and taken photography in X-rays.Three-dimensional reconstructions of vessels were made by CT and mimics with theCT-data. Results1. Facial artery and its branchesThe facial artery appears on the face at the juncture of inferior border ofmandible and anterior border of masseter. It sinuously passes upward apart from theangle of mouth and lower margin of the nasal ala respectively. The external diameterat origination, angle of mouth and lower margin of the nasal ala is 2.3±0.4mm, 1.8±0.4 mm, 1.4±0.3 mm respectively. The branches of facial artery contain anterior andposterior groups.The branches of anterior group:①The submental artery: The external diameterat origination is 0.9±0.2mm, the occurrence rate is 43.8％.②The inferior labialartery: The external diameter at origination is 1.2±0.4mm, the occurrence rate is87.5％.③The superior labial artery: The external diameter at origination is 1.3±0.3mm, the occurrence rate is 93.8％.④The ramus anastomoticus of infraorbitalartery: The external diameter at origination is 0.6±0.2mm, the occurrence rate is46.9％.⑤The inferior artery of fibra nasi: The external diameter at origination is1.0±0.3mm, the occurrence rate is 87.5％.⑥The nasal wing's artery: The externaldiameter at origination is 0.8±0.2mm, the occurrence rate is 84.4％.⑦The lateralnasal artery: The external diameter at origination is 0.8±0.2mm, the occurrence rateis 84.4％.⑧The angular artery: The external diameter at origination is 0.5±0.1mm,the occurrence rate is 28.1％.The branches of posterior group:①The mascular branches of facial artery:The external diameter at origination is 1.0±0.1mm, the occurrence rate is 25％.②The buccal branch of facial artery: The external diameter at origination is 0.7±0.2mm, the occurrence rate is 90.1％.③The zygomatic branch of facial artery: Theexternal diameter at origination is 0.7±0.2mm, the occurrence rate is 43.8％.2. Superficial temporal artery and its branches ①The transverse facial artery: The external diameter at origination is 1.7±0.5mm, the occurrence rate is100％.②The zygomatico-orbital artery: The externaldiameter at origination is 0.8±0.2mm, the occurrence rate is 50％.3. Ophthalmic artery and its branches①The supratrochlear artery: The external diameter at origination is 1.3±0.3mm, the occurrence rate is 100％.②The supraorbital artery: The externaldiameter at origination is 1.2±0.2mm, the occurrence rate is 100％.③The dorsalnasal artery: The external diameter at origination is 0.7±0.2mm, the occurrence rateis 55.2％.④The infraorbital artery: The external diameter at origination is 1.2±0.2mm, the occurrence rate is 100％.ConclusionsAll arteries of face are direct branches of three main trunks: the facial artery, thesuperficial temporal artery and the ophthalmic artery. They are supported by manyanastomoses between them.The distribution of the mentioned vessels could be systematized into fourregions. Zone 1 is the space above the inferior aspect of the orbital rims. Zone 2 is thespace between the inferior orbital rim and the base of the columella. Zone 3 is thespace between the base of the columella and the buccal commissures. Zone 4 is thespace between the buccal commissures and the line across the mandibular border.Zone 1 contains the supraorbital artery, supratrochlear artery and dorsal nasalartery, which originate from the ophthalmic artery; and the zygomatico-orbital artery,which comes from the superficial temporal artery; Zone 2 contains the lateral nasalartery and nasal wing's artery, which are branches of the facial artery; the transversefacial artery, which comes from the superficial temporal artery;and the infraorbitalartery, which originate from the ophthalmic artery. Zone 3 includes two pairs ofarteries, the superior labial artery and the septal artery, both of which originate from the facial artery. Finally, Zone 4 contains the inferior labial artery and the submentalartery, which also originate from the facial artery.When performing the nasolabial flap, which the facial artery is a pedicle, theincision should be at the lateral 1.5cm of inferior border of nasal wing.That couldavoid to injury the facial artery, and the incision is hiding.The labial arc is composed of the superior labial artery and the inferior labialartery, which exists constantly and has different types. When the transfer of a labialflap is applied to correct the deficiency of the lip, it is necessary to stress that themajor role of the labial artery for an excellent vitality of the flap.When the transfer of infraorbital flap is applied, it is not necessary to dissect theinfraorbital artery and nerve. The flap could has excellent vitality just with 1.0cm×0.5cm~2 subcutaneous tissue. The flap has sensation as the infraorbital nerve isaccompanied with the infraorbital artery.The supratrochlear artery goes forward superior and lateral, so there is a regionlike lumbar triangle (The high is 6cm) between the supratrochlear arteries in whichthere is no great vessels, no great ramus anastomoticus, just a vessels rarefied area.The lateral-center frontal flap should be used instead of the center frontal flap.Part Three Applied anatomy of the facial trunkObjective To study the microsurgical anatomy of the facial nerve (FN) trunkand provide some important morphometric data about facial-hypoglossal nerveanastomosis (FHA).Methods Bilateral microsurgical dissection was performed with three different methods on 9 human heads fixed with formalin. The first method utilized theposterior belly of the digastric muscle as a landmark, and the FN was identified onthe medial side of this muscle. In the second method, dissection was initiated at theparotid gland, the FN was identified at its entrance into the parotid gland. In the thirdmethod, the styloid process was identified and traced back to the stylomastoidforamen (SMF). The FN trunk was identified on its emergence from the SMF. Inevery dissection, the whole trunk of the FN was exposed; Its diameter and depth atthe the SMF and its length were measured; Its relationship with other structures werestudied.Results The FN invariably emerged from the cranial base through the SMF.Its diameter upon its emergence from the foramen was 2.57±0.60 mm. The meanminimal distance of the FN trunk from the skin surface in this area was 22.62±2.88mm. The length of the FN trunk was 15.71±1.97mm. The distance between thebifurcation and the mastoid tip was 18.20±4.41 mm. The distance between thebifurcation and the mandibular angle was 39.91±8.38 mm. The distance between themastoid tip and the SMF was 17.91±2.68 mm. Branches from the FN trunk proximalto its bifurcation were the posterior auricular nerve, the digastric muscle nerve andthe stylohyoid muscle nerve.Conclusions The third method to expose the trunk of the FN on its emergencefrom the SMF is safe and reliable. It is feasible to use only part of the hypoglossalnerve fibers for anastomosis with the FN trunk.Part Four Applied anatomy of the greater omentum in the plasty of face Objective To observe the shape, size, position and vessels of greater omentum.To explore the design of greater omentum and clarify its clinical significance.Methods Three fresh and twelve formalin-fixed cadaveres were dissected. Allof them had no destroy and injury.1. Macro-micro-dissection: The shape, size, position of greater omentum wasobserved. The vessels of the greater omentum were studied. 2. Lead oxide-gelatininjection technique and three-dimensional reconstruction: A fresh female adultspecimen was injected lead oxide-gelatin at femoral artery. 24 hours later, thespecimen was scanned by CT, and then the soft tissues of stomach, transverse colon,spleen and great omentum were taken from the body. The soft tissues were rescannedby CT and taken photography in X-rays. Three-dimensional reconstructions of vesselswere made by CT and Mimics with the CT-data.Results The length of greater omentum is 24.7±6.9cm, the width is 28.3±2.8cm. It could be divided into 3 types: thin type, middle type and thick type, theoccurrence rate is 33.3％, 46.7％, 20％respectively.The blood supply of greater omentum is abundant. The arteries mainly comefrom the gastroepiploic arch composed of the left gastroepiploic artery and the rightgastroepiploic artery. There are 4 main arteries of the greater omentum:①The rightepiploic artery: It comes from the right part of gastroepiploic arch, goes down anddistributes the right part of greater omentum. The external diameter at origination is1.0±0.4mm.②The middle epiploic artery: It comes from the middle part ofgastroepiploic arch, goes down and distributes the middle part of greater omentum.The external diameter at origination is 0.7±0.3mm.③The left epiploic artery: Itcomes from the left part of gastroepiploic arch, goes down and distributes the left partof greater omentum. The external diameter at origination is 1.2±0.4mm.④Theaccessary epiploic artery: It comes from the right part of gastroepiploic arch, located right side of the right epiploic artery, goes down and distributes the right part ofgreater omentum. The external diameter at origination is 0.5±0.1mm.Conclusions The greater omentum is a broad, quadruple-layered sheet ofperitoneum. The greater omentum hangs down from the greater curvature of thestomach and the proximal part of the duodenum. After descending, it folds back andattaches to the anterior surface of the transverse colon and its mesentery.The blood supply of greater omentum mainly comes from the gastroepiploicarch composed of the left gastroepiploic artery and the right gastroepiploic artery.There are 6 arteries of the greater omentum: the right epiploic artery, the middleepiploic artery, the left epiploic artery, the accessary epiploic artery, the short epiploicartery,According to the characteristic of the anterior arch and posterior arch, the positionof the middle epiploic artery divarication and the method of spread, the greateromentum is divided into 5 types. It should be according to the characteristic, whenthe greater omentum is designed and clipped.