Учебники / Rhinoplasty Dissection Manual Toriumi 1999
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Figure 5. Spreader grafts may be secured first with ab sorbable suture to the septum to stabilize them in position. (We recommend 5-0 PDS, or other similar suture).
Figure 6. Spreader grafts sutured into position. Several hor izontal mattress sutures secure the spreader grafts and up per lateral cartilages . A needle of adequate size (such as a PS-2) facilitates engaging all structures (upper lateral carti lage-to-spreader graft-to-septum-to-spreader graft-to-upper lateral cartilage) in a single pass. Note how this suture passes through the dorsal edge of the upper lateral cartilage.
grafts may be secured first to the septum to stabilize them in position (Fig. 5). Alterna tively (and commo nly), simply engage all structures (uppe r lateral cartilage -to-spreader graft-to septum-to-spreader gra ft-to-upper lateral cartil age) with a single mattress suture (Fig. 6). An additional horizontal mattr ess suture may be necessary to secure the spreader grafts and upper lateral cartilages in position . A needle of adequ ate size (such as a PS-2) facilit ates en gaging all structures in a single pass (Fig. 6). Do not cinch down the mattress sutures too tightly or inferiorly, or else the upper lateral cartila ges may actually be forced mediall y.
SPREADER GRAFTS
In the absence of other causes of nasal obstruction , the nasal valve and nasal valve area constitute the flow -limit ing seg ment of the nose. Th e nasal valve is bounded by the caudal border of the upper lateral cartilage and the nasal septum, which join at an angle of 9 de grees to 15 degree s in the norm al Caucasian nose (Fig. 7). A valve fulfills the definition of a movable structure that regulates the flow of gas or fluid. The nasal valve area includes the cross-sectional area described by the nasal valve and is affected by the in ferior turbinate, the caudal septum, and the tissues surrounding the pyriform aperture (Fig. 7). The nasal valve area is con sidered to be the location of the least cross-s ectional area in the nose and is belie ved to regulate significantly both nasal airflow and resistance and the velocity and shape of the air stream. The nasal valve area is the major flow -resisti ve segment of the nasal airway (I ).
An overnarrow nose in the middle third, whether congenital or (more commonly) the consequence of previous surgery or trauma, requires cartilage graft augmentation to im prove the airway and restore aesthetic balance. Examinati on may reveal an overnarrow an
Figure 7. Nasal valve and nasal valve area.
gle at the nasal valve area, medi al coll apse of the valve on even modes t inspi ration, or col lapse of the upper lateral cartilage against the septal wall , effecti vely compromising the air way. Spreader graft s act as spacers between the upper lateral cartila ge and septum, cor recting an overnarrow middl e vault and internal nasal valv e or preventing excessiv narrow ing in the high-risk patient (2-10).
A submucoperichondrial tunnel on one or both sides of the dorsal aspect of the septum may be prep ared by elev ating the mucoperichondrium bridging the upper lateral cartilage to the septum. Thi s dissection provides a space to be filled by a cartilage graft insinuate into the pocket, lateralizing the upper lateral cartil age(s), improving the airw ay and effec tivel y widenin g, when indic ated , the appearance of the middle third of the nose. In our ex perience, spreader grafts are mo re effective when the fibrous connections between the dor sal septum and upper lateral cartilage are left intact. Applicati on of the spreader graft creates a cantilever effect and aids in lateralizing the upper lateral cartilage to provide max imal airway improvement.
Whereas spreader grafts may be comfortably carried out through traditional endonasa techniques (2), in more complex recon structi ons, particularly complicated by multiple ab norm alities, an external rhinopl asty approach may facilitate accurate dissection and graf suture fixation (6) .
When the T-shaped configuration (horizontal exten sion) of the nasal septum is resected with dorsal-hump remov al, narrowing of the middle nasal vault may be problematic in th high-ri sk patient. Identifying the high -risk patient during initial preoperative analy sis is es sential to the prevention of excessi ve narrowing of the middle nasal vault with interna nasal valve collapse. An anatomic variant referred to as the "narrow-nose syndrome" ha been described (2,6). Short nasal bon es, long weak upper lateral cartilages, thin skin, an a narrow projecting nose pred ispose to middle vault collapse . A large en bloc hump re moval should be avoided, as the T-sh aped horizontal support of the nasal septum is elimi nated and the intran asal mucosa (which provides support to the upper lateral cartilage) is a risk of injury . Regardles s of the approach to the middle vault, keepin g the intrana sal mu cosa intact with execution of profile alignment (dorsal-hump removal) helps maintain im portant support of the upper lateral cartilages (see Chapter 6, Fig. 5). This can be achieved by dissectin g submucosal tunnels and freeing the upper lateral cartilages from the septum before cartil aginou s hump remov al. Alternatively, conservative hump excision followed b millimeter-by-mill imeter shaving of the uppe r later als und er direct vision preserve s the in tranasal muco sa.
Coll apse of the middle nasal vault may highlight the caudal edges of the nasal bones t produce the characteristic "inverted V" deformity (Appendix G) .
When the dorsal hump has been taken down and the upper lateral cart ilages appear desta bilized , such as in the high-risk patient, suturing the upper lateral cartilages back to the sep tum can be helpful to prevent middle nasal vault collapse. Spreader graft s applied between
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pre ser ve an ade quate nasal valve . An external rhinoplasty approach may faci litate accurate graft-suture fixa tion in this setting. These precautionary maneuvers are not necessary in all cases but may prevent problems in the high-risk pati en t (6) .
Commo nly performed surg ica l maneuvers can result in loss of support to the midd le vault. Cephalic him (volu me redu ction) of the lateral crura disrupts the scro ll (rec urvature) and frees the ca uda l margi n of the upper lateral cart ilage . Lateral osteotomies may further medi alize the upper lateral cart ilages . T he upper lateral car tilages can fall toward the narrowed dorsal sept al edge, producing narr owin g of the middl e vault and internal valv ular collapse. In the majority of pa tients, the combi nation of these m aneu vers will not result in a pro blem; however, in high-ri sk patients (narrow-nose syndrome), this combination of maneu vers may co ntri bute to excessive narr owin g of the middle vault with internal valve co llapse.
W hen spreader grafts are used , appropria te spreader-graft thickn ess will achieve the de sired fun ction al effect wi tho ut causi ng overwide ning . Great care sho uld be taken to avoid overwide ning if poss ible. Experi ence is required to deve lop relia ble surg ical judgment re garding the appropriate width and length of spreade r grafts. Careful palp ation of both up per lateral cartilages can aid in ver ifying symmetry of the middle nasal vaults.
Spreader grafts are usually 1 mm to 3 mm in thickness . It is ge nerally better to use thin ner spreader grafts because if the midd le vault is too wide, rev isio n surgery wi ll be nece s sary. After spreader grafts are secured in pos ition via the externa l app roach , or if they are placed endo nasa lly after dissection of the soft-tissue enve lope , the middl e-vaul t width can be assessed by inspect ion and palpa tion . T he middle vault sho uld be no wider than the bony vault and nan-owe r tha n the nasal tip. If excessive width or as ymm etry is noted, the grafts should be rep ositi on ed or narrowed, O ver time, this area of the nose tend s to nalTOW as edema resolv es and sca r contracture pulls the upper lateral cartilages mediall y.
Asy mme try of the middle nasal vau lt may at times be addressed with the placement of a unilateral spreader gra ft, or alterna tive ly, with the placement of sprea der grafts of unequ al thickn ess (Fig . 8) ( 10). In most cases, we prefer to use bilateral spreader grafts to splint de viations of the dorsal sep tum and preven t worsening of the dorsal septal devia tio n.
A variety of other maneuvers are at the surgeon ' s disposal in addressing the middle nasal vault. O nlay cartilage wafer grafts, derived from the sep tu m or ea r, effective ly ef fac e and imp rove middle-third depression s, but may be used to improve aes thetics only when airway blockage does not exist as a co nse que nce of midd le-va ult co llapse . Ca reful preop erati ve ana lysis sho uld determine the need for ot her supportive and reco nstruc tive
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Figure 8. Spreader grafts may be applied unilaterally or asymmetrically to camouflage asymmetry of the middle nasal vault.
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4. Johnson CM, Toriumi DM. Open structure rhin oplasty. Philadelphi a: WB Saunders, 1990.
5.Toriumi DM , Johnson CM . Open structure rhinoplasty: featured technical points and long-term follow-up .
Facial Plast Surg Clin North Am 1993 ;I:1-22.
6. Torium i DM . Management of the middle nasal vault in rhinoplasty . Oper Tech Plast Reconst r Sur g 1995 ;2: 16-30.
7. Constantian MB, Clardy RB. The relativ e importanc e of septal and nasal valvular surgery in correcting air way obstruction in primary and secondary rhinoplasty. Plast Recon str Su rg 1996;98:38-54.
8.Te ichgrae ber JF, Wainwri ght DJ. The treatment of nasal valve obstructi on. Plast Re constr Surg 1994;9 3: 1174-11 84.
9.Aiach G. Atlas de rhinopl astie. Paris: Masson , J 989:74-85.
10. Toriurni DM, Ries WR. Innovativ e surgical managem ent of the crooked nose. Facial Plast Su rg Clin No rth A/11 1993;1:63-78.
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9
Surgery of the Nasal Tip
EXERCISES (Appendix F)
Placement of Columellar Strut
The placement of a rectangul ar cartil age strut between the medial crura can improve tip support and augment tip projection. A colume llar strut also can be used to correct buckled medi al or intermediate crura or to increase columellar show. The strut may be placed by us ing the externa l approac h or into a precise pocket via the endonasal approach.
Placement of Columellar Strut via an External Rhinoplasty Approach
The area between the medial crura is dissected to create a pocket to place the strut. The rect angular cartilage strut typically measures 8 mm to 12 rnm in length, 3 mm to 4 mm in width, and 1 mm to 2 mm in thickness. Th e strut is most typically fashioned from harvested septal cart ilage, but also, when necessary, from auricul ar cart ilage, and at times from rib cartilage. The strut is positioned so that it sits above (without extending to) the nasal spine (Fig. 1). It is preferable to leave a small soft-tissue pad between the strut and the nasal spine. The strut should not extend above the intermediate crura . It is secured to the medial crura with several absorbable mattress sutures (e.g., 4-0 plain gut, Keith needle) placed through the vestibular skin. Asymme tries of the lower lateral cartilage (LLC) may be improved with placement of the strut (Fig. 2). Asymmetry of the tip may be created if the medial crura are asymmet rically sutured to the strut (Fig. 3), or if an overlong strut extending beyond the nasal spine shifts to the side of the nasal spine, thereby causing a deviated nasal tip (Fig. 3) ( 1,2).
Placem ent of Columellar Strut via an Endonasal Approach
A small incision is made throu gh the vestibular skin and ipsilateral medial cr us (Fig. 4). Scissor dissecti on creat es a precise pocket through this small incision (Fig. 5). The col
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