Surgicl mngement of ostructive sleep pne PUSHKAR MEHRA, BDS, DMD, AND LARRY M. WOLFORD, DMD Ostructive sleep pne (OSA) syndrome is common disorder tht hs recently received much ttention y the medicl community due to its potentilly serious physiologicl consequences. The clinicl significnce of OSA results from hypoxemi nd sleep frgmenttion cused y collpse of the irwy, which leds to pne or hypopne during sleep. This pper reviews common surgicl techniques used for clinicl mngement of OSA ptients, with emphsis on jw dvncement surgicl procedures. Ostructive sleep pne (OSA) syndrome is reltively common disorder tht involves periodic prtil or totl collpse of the phryngel irwy during sleep. This results in progressive sphyxi, which incresingly stimultes rething efforts ginst the collpsed irwy, typiclly until the ptient is wkened from sleep (1). Clinicl sequele of OSA result from the hypoxemi nd sleep frgmenttion (2). The respirtory disturnce index is the numer of pneic or hypopneic events per hour during sleep, determined y polysomnogrphy, nd is used to quntify the severity of OSA. Additionl symptoms include snoring, dytime sleepiness, nd ftigue. As OSA progresses, cognitive dysfunction, inility to concentrte, memory nd judgment impirment, irritility, nd depression cn develop, leding to work nd socil prolems. Systemic consequences of OSA include hypertension, crdic rrhythmis, pulmonry hypertension, cor pulmonle, left ventriculr dysfunction, stroke, nd deth (2). Nonsurgicl options for treting OSA include weight loss, ltertion of sleep posture, orl pplince therpy, externl nsl support devices, phrmcologicl therpy, nd continuous positive irwy pressure (CPAP) therpy (1). Surgicl tretment options include trcheostomy, mndiulr osteotomy with genioglossus or inferior order dvncement, uvulopltophryngoplsty (UPPP), lser-ssisted uvuloplsty (LAUP), reduction glossectomy, internl nd externl nsl reconstruction, tonsillectomy nd denoidectomy, nd dvncement of the upper nd lower jws. We review the vrious surgicl techniques nd present some of our clinicl nd reserch experience in the mngement of ptients with OSA syndrome. TRACHEOSTOMY Permnent trcheostomy ws the first efficcious procedure nd the most common procedure used for tretment of OSA in the 1970s nd 1980s (3, 4). Trcheostomy hs very high success rte in reversing OSA symptoms, except possily for ptients Figure 1. () The nterior mndiulr osteotomy with genioglossus dvncement procedure. A surgicl ccess window is creted in the nterior mndile y cutting through the outer nd inner cortices nd medullry one. () The outer cortex nd medullry one hve een removed. The inner cortex incorporting the genil tuercles (with ttched musculture) hs een nteriorly repositioned replcing the removed outer cortex. This simultneously dvnces the hyoid one nd se of the tongue (T) (rrows). with oesity-hypoventiltion syndrome, s it ypsses ll potentil upper irwy ostructive sites. Despite its effectiveness, trcheostomy is rrely used s first-line tretment of OSA ecuse of serious disdvntges, which include trchel stenosis, lood vessel erosion, recurrent purulent ronchitis, speech difficulties, nd esthetic disfigurement. ANTERIOR MANDIBULAR OSTEOTOMY WITH GENIOGLOSSUS ADVANCEMENT This procedure involves n osteotomy in the nterior mndile, creting lock segment tht incorportes the genil tuercles nd ssocited muscle ttchments (Figure 1). The ony lock is then repositioned nteriorly to dvnce nd suspend the hyoid one to the mndile (Figure 1). Riley et l reported 67% success rte, with filures relted to oesity nd norml mndiulr skeletl development (5). This procedure hs the dvntges of eing offered on n outptient sis nd eing reltively minimlly invsive. Its disdvntges re tht it does From the Deprtment of Orl nd Mxillofcil Surgery, Bylor University Medicl Center, Dlls, Texs. Dr. Mehr is now with the Deprtment of Orl nd Mxillofcil Surgery t Boston University School of Dentl Medicine, Boston, Msschusetts. Corresponding uthor: Lrry M. Wolford, DMD, 3409 Worth Street, Suite 400, Dlls, Texs 75246. 338 BUMC PROCEEDINGS 2000;13:338 342
gittion, velophryngel incompetence, hypernsl speech, pltl stenosis, nd residul OSA. Wolford developed modifiction of the trditionl UPPP procedure tht minimizes incisions long the posterior order of the soft plte, decreses postsurgicl scrring, nd predictly shortens the soft plte length, effectively improving the orophryngel irwy spce fter surgery (Figure 3). Figure 2. () The nterior mndiulr horizontl osteotomy with genioglossus muscle nd inferior order dvncement (genioplsty). The osteotomy is mde through oth outer nd inner cortices of the mndile. () The genioplsty segment hs een dvnced, cusing simultneous dvncement of the hyoid one, se of the tongue (T), nd inferior order of the mndile (rrows). not enlrge the orl cvity; genioglossus muscles cn ecome detched, negting its effectiveness; nd it is not effective in more severe OSA cses. ANTERIOR MANDIBULAR OSTEOTOMY WITH INFERIOR BORDER ADVANCEMENT (GENIOPLASTY) This procedure consists of n nterior mndiulr horizontl osteotomy with genioglossus muscle nd inferior order dvncement (Figure 2). Advntges nd disdvntges of this technique re similr to those of the Riley technique descried ove (5). However, this procedure results in chnge in fcil profile nd my e eneficil for ptients with esthetic deficiency in the chin re. LASER-ASSISTED UVULOPLASTY LAUP hs gined populrity for tretment of snoring with reports of 80% to 85% success rtes (4). Its dvntges over UPPP re tht it is n outptient procedure under locl nesthesi, it cn e repeted, nd it hs decresed postopertive complictions. However, recent report on the efficcy of LAUP for treting OSA showed tht 27% of the ptients hd good response, 34% hd poor response, nd 30% got worse fter surgery (12). REDUCTION GLOSSECTOMY True or reltive mcroglossi my e oserved in some OSA ptients (4, 13). An enlrged tongue cn decrese the posterior irwy spce (PAS) t the orophrynx. Computerized xil tomogrphy hs confirmed tht tongue volume increses with incresing oesity. However, the tongue my e of norml size ut pper lrger thn norml if the volume of the orl cvity is decresed ecuse of retropositioned jws. If true mcroglossi exists, reduction glossectomy cn e done, removing the nterior nd portion of the middle third of the tongue (Figure 4). Tste nd senstion re minimlly ffected fter surgery (4, 13). Wolford et l hve previously presented the dignosis, indictions, techniques, nd results of reduction glossectomy for tretment of mcroglossi (13). UVULOPALATOPHARYNGOPLASTY UPPP ws first descried y Ikemtsu in 1964 for tretment of hitul snoring (6). Fujit et l modified the technique to increse the orophryngel irwy spce y excising the uvul nd 8 to 15 mm of the posterior spect of the soft plte, s well s the redundnt lterl phryngel wll mucos (7). Although UPPP hs resulted in symptomtic improvement from hitul snoring in up to 90% of cses, only 41% to 66% of ptients see improvement or elimintion of OSA nd results my worsen over time (8 11). The reson UPPP cn fil is tht the procedure ddresses the ostruction t the soft plte re only, without improving the irwy t the se of the tongue (hypophryngel re) or nsl cvity. In ddition, scr contrcture t the posterior order of the soft plte cn crete curtin effect, pulling the soft plte downwrd ginst the tongue nd cusing significnt trnsverse nrrowing etween the posterior fucil pillrs, further contriuting to OSA. Complictions from UPPP include nsl regur- c Figure 3. () Wolford s modified uvulopltophryngoplsty procedure. Note the hypertrophic uvul nd the nrrow trnsverse dimension etween the right nd left fucil pillrs. The incisions re outlined t the se of the posterior fucil pillr ilterlly nd t the se of the uvul. () Following completion of incisions, the uvul flps re closed. Dissection into the lterl spect of the soft pltl tissues is performed in sumucosl plne etween the orl nd nsl sides with right-ngled scissors. A mttress suture is pssed sumucoslly from the se of the mxillry tuerosity to the dissected lterl flp of the posterior fucil pillr. The suture is pssed through the end of the flp nd tunneled ck to the mxillry tuerosity re. The sutures re then tightened to shorten the soft plte to the desired dimension. (c) Postsurgicl view of the velophryngel structures fter modified uvulopltophryngoplsty procedure. Note the incresed trnsverse dimension of the orophryngel irwy fter lterliztion nd forwrd positioning of the posterior fucil pillrs. OCTOBER 2000 SURGICAL MANAGEMENT OF OBSTRUCTIVE SLEEP APNEA 339
c Figure 4. () The keyhole technique is used for surgicl reduction of tongue size. Mrkings show the plnned incisions. () The nterior middle prt of the tongue hs een resected nd removed. (c) Suturing of the tongue reestlishes ntomic continuity nd physiologic function, with the tongue eing reduced in length nd width. NASAL RECONSTRUCTION Procedures such s nsoseptoplsty, nsl turinectomies, columell nrrowing, enlrgement of the luminl vlves, nsl polypectomies, nd reconstruction of externl crtilge nd one my e indicted for correction of nsl irwy ostruction. These re usully used s djuncts in comintion with other surgicl procedures ecuse their role in treting multilevel OSA is very limited. TONSILLECTOMY AND ADENOIDECTOMY Hypertrophied tonsillr nd denoid tissues cn contriute to irwy ostruction t the nsophryngel nd orophryngel levels, especilly in children nd dolescents. Clinicl nd rdiogrphic (lterl cephlometric x-ry) exmintion, s well s nsophryngoscopy, cn usully identify involvement of these structures. Tonsillectomy nd denoidectomy cn e performed to eliminte the ostructions. MAXILLOMANDIBULAR ADVANCEMENT SURGERY (ORTHOGNATHIC SURGERY) Over the pst few yers, comined dvncement of the mxill nd mndile hs ecome the surgicl procedure of choice for tretment of OSA in ptients with decresed orophryngel irwys, nd numerous studies hve reported the eneficil effects on the PAS (13 17). Studies hve shown tht ptients with diminished crosssectionl re of the phrynx my e predisposed to phryngel collpse nd OSA (18, 19). It hs een clerly documented tht mxillomndiulr dvncement surgery is very efficcious in eliminting OSA y enlrging the PAS nd tightening the upper irwy muscles nd tendons (velophryngel nd suprhyoid muscles) y dvncement of their ony origin (15 20). Prevlence of OSA hs lso een linked to specific fcil morphology types. Prchrktm et l found tht vriles relted to soft tissues, hyoid one to mndiulr plne, ody mss index, nd soft plte length hd the highest predictive vlue (18). Riley et l reported tht PAS of <11 mm nd mndiulr plne hyoid one ngle >15.4 were indictive of OSA (21). Mxillomndiulr dvncement surgery hs the enefits of correcting the ptient s fcil nd occlusl deformities while lso ddressing OSA symptoms very effectively y enlrging the size of the orl cvity nd pulling the se of the tongue nd soft plte forwrd, thus incresing the PAS. PRESURGICAL CONSIDERATIONS Plnning the skeletl, soft tissue, nd dentl correction of crniofcil deformities requires comprehensive collection nd nlysis of dt from vrious sources, including the ptient s description of the prolem nd medicl nd dentl history, clinicl evlution, rdiogrphic exmintion, nd dentl model nlysis. Orthodontic nd dentl tretment my e required efore nd/or fter surgery to mximize the functionl nd esthetic results of the orthognthic surgicl procedures performed. Creful ttention is pid to the evlution of the fcil form in ll 3 dimensions. Besides the clinicl exmintion, the lterl cephlometric rdiogrph is of prticulr vlue, s it gives informtion out the fcil skeletl nd soft tissue structures s well s the PAS (norml dimension is 11 ± 2 mm) (16). The PAS in OSA ptients is often nrrower thn in norml controls (22 24). Although PAS evlution on lterl cephlometric rdiogrph represents only 2-dimensionl overview of 3-dimensionl prolem nd is not tken in supine sleeping position, when properly tken it provides very useful informtion in evluting the ntomic interreltionships of the irwy structures nd in estimting tongue nd nsophryngel volume. Bony nd soft tissue lndmrks on the lterl cephlometric rdiogrph re nlyzed with specific ngulr nd liner mesurements to id in dignosis nd tretment plnning. Surgicl tretment ojective trcings re constructed to predict the surgicl movements required to correct the OSA nd ny coexisting ssocited fcil deformity. The surgery is then simulted on dentl plster models of the ptient s teeth nd jw structures mounted on jw rticultor. Acrylic surgicl stilizing splints re fricted in the lortory on these plster models, which reflect the jws in their new position. These surgicl splints help in the ccurte repositioning of the jws during surgery. SURGICAL PROCEDURES The most common orthognthic surgicl procedures used in OSA correction re the mxillry Le Fort I osteotomy nd the ilterl mndiulr rmus sgittl split osteotomy. Using oth mxillry nd mndiulr osteotomies usully llows for greter dvncement of the jw structures in OSA tretment, providing etter outcome. Wolford et l were the first to show tht orthognthic surgery with counterclockwise dvncement of the mxill nd mndile mximizes the increse of the PAS while lso optimizing fcil esthetics (25, 26). Adjunctive procedures to correct irwy ostruction in other res (e.g., septoplsty, turinectomies, externl nsl reconstruction, modified UPPP, reduction glossectomy, tonsillectomy, denoidectomy) cn e performed concurrently with the jw surgery. Bone pltes nd screws re used to rigidly stilize the jw structures during surgery. This elimintes the need for wiring the jws together fter 340 BAYLOR UNIVERSITY MEDICAL CENTER PROCEEDINGS VOLUME 13, NUMBER 4
surgery, therey incresing ptient comfort, permitting immedite ctive jw function, improving dietry intke nd orl hygiene, llowing norml speech, nd minimizing chnces of irwy compromise immeditely fter surgery. CLINICAL AND RESEARCH EXPERIENCE The senior uthor of this pper (Dr. Wolford) hs >20 yers of experience in using orthognthic surgery for tretment of OSA. We hve oserved tht mny ptients with OSA symptoms hve common clinicl nd rdiogrphic chrcteristics, including retruded mndile, retruded mxill, posterior verticl mxillry deficiency, retropositioned tongue, high occlusl plne nd high mndiulr plne ngultions, short chin-neck line, nd decresed PAS on lterl cephlogrm (25). Other chrcteristics tht my e present include nsl irwy ostruction (e.g., nrrow nostrils, wide columell, enlrged turintes, devited septum, polyps, nsophryngel denoid tissue, decresed posterior chonl height, constricted luminl vlves, externl nsl deformity) nd orophryngel normlities (e.g., elongted soft plte nd uvul, medilly nd posteriorly positioned posterior fucil pillrs, enlrged denoids, hyperplstic tonsils, mcroglossi). Cliniclly, the tongue my pper lrge nd retropositioned due to the decresed orl cvity volume resulting from the retruded position of the jws. c d Ptients nd methods We performed retrospective study to evlute the effects of orthognthic surgery on the PAS ntomy. The tretment records of 72 ptients (14 men, 58 women) operted on y Dr. Wolford for correction of dentofcil deformities (not ll with OSA) t Bylor University Medicl Center were retrospectively nlyzed. All ptients underwent Le Fort I mxillry osteotomies nd mndiulr rmus sgittl split osteotomies with rigid fixtion for counterclockwise dvncement of the mxillomndiulr complex. Although mny of these ptients hd turinectomies nd nsoseptoplsties t surgery, none hd ony genioplsties, UPPP, denoidectomies, tonsillectomies, or reduction glossectomies. Stndrdized lterl cephlometric rdiogrphs were tken efore surgery (T1) nd t longest follow-up (T2) intervls. T1 nd T2 rdiogrphs were trced on cette sheets nd superimposed y n exminer to ssess chnges in phryngel ntomy. The PAS dimensions were clculted y mesuring the nrrowest dimension from the posterior phryngel wll to the tongue se nd to the soft plte. A Student t test ws used to ssess the sttisticl significnce of results. A P vlue <0.0001 ws considered sttisticlly significnt. Results The verge ge of the ptient smple ws 36.3 yers (rnge, 12 to 56 yers), nd the verge follow-up time ws 3 yers (rnge, 1 to 8.1 yers). The men mndiulr dvncement ws 12 mm (SD, 5.4) mesured t the genil tuercles. The men mxillry dvncement t point A ws 5.1 mm (SD, 2.1). At the soft plte, the men PAS presurgery ws 7.9 mm (SD, 2.8) nd postsurgery ws 14.1 mm (SD, 3.7), for men increse of 6.2 mm (P < 0.0001; SD, 3.1). At the tongue se, the men PAS presurgery ws 7.7 mm (SD, 2.6) nd postsurgery ws 15.8 mm (SD, 3.6), for men increse of 8.1 mm (P < 0.0001; SD, 3.6). Figure 5. () Frontl view of 49-yer-old womn who ws referred y her physicin for correction of OSA symptoms. () Profile view shows the presence of dentofcil deformity with retruded upper nd lower jws. (c) The ptient 5 yers fter mxill nd mndile dvncement nd intrnsl surgery. The sleep pne symptoms hve een eliminted. (d) Profile view shows good esthetic result with hrmonious fcil lnce. Thus, the men PAS increse rnged from 52% to 63% of the mount of mndiulr dvncement performed. No ptients hd ny significnt OSA symptoms t longest follow-up. CASE PRESENTATION A 49-yer-old womn (Figure 5, 5) ws referred for tretment of OSA symptoms y her physicin. She gve history of loud snoring while sleeping, dytime somnolence, generlized ftigue, nd nsl irwy ostruction. She hd een using CPAP mchine while sleeping for 1 yer prior to presenttion, without significnt relief of symptoms. Other previously filed nonsurgicl OSA therpy included weight loss, use of medictions, nd orthodontic/dentl pplince therpy. A presurgicl polysomnogrphic study showed severe sleep pne with respirtory disturnce index of 51 nd men oxygen sturtion of 84%. Presurgicl clinicl nd rdiogrphic evlution (Figure 6) reveled dignosis of 1) mndiulr retrusion; 2) mxillry retrusion; 3) posterior verticl mxillry deficiency; 4) severely decresed PAS (2 mm); 5) high occlusl nd mndiulr plne ngles; 6) devited nsl septum; 7) hypertrophied nsl turintes; 8) wide nsl columell, creting nrrow nostrils; nd 9) nsl irwy ostruction cused y the 3 previous dignoses. After the necessry orthodontic tretment ws completed, the following surgicl procedures were performed t 1 opertion OCTOBER 2000 SURGICAL MANAGEMENT OF OBSTRUCTIVE SLEEP APNEA 341
Figure 6. () Presurgicl trcing of the dentofcil structures on the lterl cephlometric x-ry. Note the nrrowed PAS of 2 mm (norml is 11 ± 2 mm). () Postsurgicl trcing of the dentofcil structures on the lterl cephlometric x-ry showing the effects of surgery performed on the upper nd lower jws. Note the incresed dimension of the PAS to 13 mm t the tongue se nd 9 mm t the soft plte. (Figure 6): 1) multiple-segment Le Fort I osteotomies to dvnce the upper jw 8 mm, 2) ilterl mndiulr rmus sgittl split osteotomies to dvnce the lower jw 16 mm, 3) 5-mm chin implnt, 4) nsl septoplsty; 5) ilterl prtil inferior turinectomies, nd 6) nsl columellr nrrowing to enlrge the nostrils. The chin point dvnced 21 mm forwrd from its presurgicl position (s result of the mndiulr dvncement nd chin implnt). The PAS t the tongue se incresed to 13 mm (650% improvement from the presurgery PAS of 2 mm) nd t the soft plte level incresed to 9 mm (450% improvement from the presurgery PAS of 2 mm) (Figure 6). 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