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Z-palatopharyngoplasty Michael Friedman, MD, FACS,a,b,c Michelle S. Hwang, BSb From the aRush University Medical Center, Chicago, Illinois; bAdvanced Center for Specialty Care, Advocate Illinois Masonic Medical Center, Chicago, Illinois; and the cChicago ENT—an Advanced Center for Specialty Care, Chicago, Illinois KEYWORDS Z-palatoplasty; Obstructive sleep apnea-hypopnea syndrome; Revision uvulopalatopharyngoplasty
Palatal surgery traditionally seeks to widen the airway, reducing obstruction of the tongue base, retropalatal, and lateral dimensions. Correction of the palate with the classical uvulopalatopharyngoplasty, however, often results in a narrowed palatal arch. The Z-palatoplasty was first developed as a modification of the traditional uvulopalatopharyngoplasty, with the intent to widen the retropalatal space while maintaining or increasing the lateral space. Since its first description, the Z-palatoplasty has been modified to include tonsillectomy and lateral pharyngoplasty. We describe the author's technique and the evolution and successful application of the procedure. r 2015 Elsevier Inc. All rights reserved.
Introduction The uvulopalatopharyngoplasty (UPPP), as described by Fujita1 in 1981, marked a breakthrough for the evolving field of sleep surgery. However, the limited success and cure of obstructive sleep apnea-hypopnea syndrome (OSAHS) using this procedure resulted in the need to develop modifications of UPPP. Persistent retropalatal obstruction following traditional UPPP has remained a limiting factor to the success of UPPP.2-4 Surgical success was extremely variable, with an estimated success rate of 40%.5 Furthermore, patients who previously had tonsils removed were often poor candidates for UPPP. The zetapalatoplasty (ZPP) was first described as a modification of the UPPP in patients with absent tonsils.5 Subsequently, multiple modifications have been reported. The procedure is now used for patients with and without previous tonsillectomy. The modified procedure includes a lateral pharyngoplasty. The goal of the procedure, similar to that of the UPPP, is to widen the space between the palate and the posterior pharyngeal wall and between the palate Address reprint requests and correspondence: Michael Friedman, MD, FACS, 3000 N. Halsted St, Suite 400, Chicago, IL 60657. E-mail address:
[email protected] http://dx.doi.org/10.1016/j.otot.2015.03.008 1043-1810/r 2015 Elsevier Inc. All rights reserved.
and tongue base and to either maintain or widen the lateral dimensions of the pharynx. However, the ZPP procedure seeks to correct the problem of narrowed lateral dimensions, which can be caused by contracture of the wound in UPPP. The ZPP, a double Z-plasty applied to the palate, changes scar contraction tension lines from the anteriormedial pull in the classic UPPP to an anterior-transverse direction.
Patient selection As with all surgical treatment of OSAHS, patients should be recommended first to a trial of conservative measures, including lifestyle changes, continuous positive airway pressure (CPAP), and oral appliances. All surgical patients should have a documented history of intolerance or noncompliance to these methods of treatment. As with any other surgical procedure, adequate medical clearance and informed consent should be obtained. Patient anatomy should be carefully considered when selecting a potential ZPP patient. All patients should have noted obstruction at soft palate, determined by fiber-optic examination before procedure. Patients with and without tonsils can both be considered. As the ZPP procedure
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2 Table Friedman staging system as determined by Friedman tongue position (FTP), tonsil size, and body mass index (BMI). Stage
FTP
Tonsil size
BMI (kg/m2)
I IIa IIb III IV*
I, IIa, and IIb I, IIa, and IIb III or IV III or IV I-IV
3 or 4 0, 1, or 2 3 or 4 0, 1, or 2 0-4
o40 o40 o40 o40 440
n All patients with significant craniofacial or other anatomical abnormalities.
significantly widens the retropalatal space, it should be reserved for significantly symptomatic patients with diagnosed moderate to severe OSAHS. Friedman anatomic staging should also be considered.6,7 Patients with stages II and III diseases have historically responded poorly to UPPP, but are candidates for ZPP. Stage II is defined as having Friedman tongue position (FTP) I or II and tonsil grades 0, 1, or 2 or FTPs III and IV with tonsil grade 3 or 4. Stage III is a combination of FTP III or IV with tonsil grades 0, 1, or 2. Patients with stages II and III diseases should all have body mass index o40 kg/m2 (Table). Patients who have previously undergone conservative palatal surgery such as a classical UPPP may also be candidates for ZPP. Figure 2 Marking of the palatal flap incision. (Color version of figure is available online.)
Figure 1 Tonsillectomy is performed with cold steel to avoid tissue damage for improved healing. (Color version of figure is available online.)
Figure 3 The anterior mucosa of the palatal flap is removed to expose palatal musculature. (Color version of figure is available online.)
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Surgical technique and adjunctive procedures
Figure 4 Palatoglossus and palatopharyngeus muscles are transected. (Color version of figure is available online.)
Figure 5 Removal of distal tip followed by division of the uvula. (Color version of figure is available online.)
For patients who have tonsils, tonsillectomy is first performed with cold steel (Figure 1). On the palate, 2 butterfly-patterned adjacent flaps are outlined (Figure 2). The anterior midline margin should be marked halfway between free edge of the palate and uvula and the hard palate. The distal margin will be made up of the free edge of the soft palate and uvula. The flaps should extend laterally to the most lateral extent of the palate. After marking of the flaps, only the mucosa on the anterior aspect of the 2 flaps is removed to expose palatal musculature (Figure 3). Next, the palatoglossus and palatopharyngeus muscles are transected bilaterally (Figure 4), followed by removal of the distal tip and splitting of the uvula in the midline (Figure 5). The uvular flaps and soft palate are reflected laterally over the soft palate, and the cut ends of the palatopharyngeus muscle are advanced laterally and superiorly and sutured in place (Figure 6). This allows for lateral expansion. Meticulous 2layered closure follows, bringing the midline to anterolateral margin of the palate. Primary closure of the submucosal layer is done with 2-0 vicryl, allowing for a tension-free closure of the mucosal layer with 3-0 chromic suture (Figures 7 and 8). The end result should see 3-4 cm of distance between the posterior pharynx and palate. As the patients who receive ZPP should have Friedman stage II or III, retrolingual obstruction also needs to be addressed. In our practice, the tongue base is treated using
Figure 6 Uvula and palate are split in midline with cold knife, and uvular flaps are reflected laterally over the soft palate. Cut ends of the palatopharyngeus should be advanced laterally and superiorly and sutured in place. (Color version of figure is available online.)
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Figure 7 A 2-layered closure of tonsillar fossa and palatal flaps. Submucosal layer is first approximated with 2-0 vicryl. (Color version of figure is available online.)
either tongue base radiofrequency or submucosal minimally invasive lingual excision with or without thyrohyoid suspension.
Postoperative management and complications Similar to most palatal surgeries, complaints of postoperative pain and dysphagia are very significant. Pain is managed during overnight hospitalization with intravenous narcotics. Half of the patients who undergo ZPP, in our experience, are able to tolerate a liquid diet on postoperative day 1 and can be discharged. The other half require 48 hours of intravenous fluids and pain management before discharge. Oral steroids and oral narcotics are used after discharge for 5-12 days. Patients generally are able to return to normal diet after 12 days. Velopharyngeal incompetence (VPI), a well-known complication of UPPP, is also a notable sequelae of the ZPP procedure. VPI is seen in all patients immediately following surgery.10 Some patients may continue to notice mild VPI under stressed conditions such as laughing. VPI is resolved in all patients 3 months postoperatively, and there have been no noted cases of permanent VPI. As ZPP results in a permanent change in the anatomy of the pharynx and palate, patients often notice some changes in the sensation of swallowing and throat tightness. The absence of the uvula
Figure 8 A 2-layered closure of palatal flaps; the mucosal layer is closed with 3-0 chromic suture. (Color version of figure is available online.)
following the procedure may also result in patients complaining of a “foreign body” sensation in the throat. The likelihood of these events must be discussed with patients before procedure.
Success rate As ZPP is an aggressive procedure intended to treat patients with moderate to severe disease with Friedman anatomical stage II or III disease, treatment is combined with submucosal minimally invasive lingual excision or tongue base radiofrequency. In combination, the procedures achieve surgical success (450% reduction and apneahypopnea index o20) greater than 75% of the time. Classical cure (apnea-hypopnea index o5) is achieved in 65% of stage II patients compared with 38% in matched patient groups using UPPP.
Discussion The UPPP continues to be the most common procedure performed for surgical treatment of OSAHS. Although the efficacy of the procedure has been questioned,4,8 it remains a standard, particularly in multilevel surgery. Multiple studies have noted continued retropalatal obstruction after UPPP.2-4,9 The modified ZPP changes the direction of
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5 transpalatal advancement pharyngoplasty or genioglossus advancement for continued sites of obstruction.
Conclusions Surgical treatment of OSAHS is imperfect, and the anatomy of each patient needs to be carefully considered before operating. In our 10-year experience of performing the Z-palatoplasty, we have concluded that the procedure significantly enlarges the retropharyngeal space, improving the airway in ways that the traditional UPPP has been known to fail. Patients with Friedman anatomical stages II and III diseases and moderate to severe OSAHS are poor candidates for UPPP. We suggest that the ZPP serves as an effective surgical alternative.
Figure 9 Traditional UPPP results in anteromedial pull that narrows retropharyngeal airway in midline.
closure tension lines. By suturing the flaps of the soft palate and uvula laterally, the line of healing and contracture is lateral rather than medial (Figure 9). Furthermore, a benefit of using ZPP to correct patients with failed previous UPPP is the potential to correct nasopharyngeal stenosis, which often is not addressed with other surgical techniques for UPPP correction. There are limitations to this technique. With the significant increase in lateral dimensions of the palate, ZPP results in higher risk of VPI, which is not reversible if it becomes permanent. However, permanent VPI in a ZPP patient has never been observed. As with any other procedure, this treatment may fail. This presents a difficult situation, particularly if the patient underwent ZPP for revision of UPPP. In our experience, patients who fail will do so objectively, but will almost always still have improved subjective symptoms. Failure patients often show elimination of apneas but persistent hypopnea on polysomnogram. However, many patients will still show decreased C-reactive protein levels, possibly indicating decreased cardiovascular risk.10 In patients who fail treatment with ZPP, the surgeon should consider a retrial of CPAP before proceeding to techniques such as the
References 1. Fujita S, Conway W, Zorick F, et al: Surgical correction of anatomy abnormalities in obstructive sleep apnea syndrome: uvulopalatopharyngoplasty. Otolaryngol Head Neck Surg 89:923-934, 1981 2. Metes A, Hoffstein V, Mateika S, et al: Site of airway obstruction in patients with obstructive sleep apnea before and after uvulopalatopharyngoplasty. Laryngoscope 101:1102-1108, 1991 3. Woodson BT, Wooten MR: Manometric and endoscopic localization of airway obstruction after uvulopalatopharyngoplasty. Otolaryngol Head Neck Surg 111:38-43, 1994 4. Woodson BT: Retropalatal airway characteristics in uvulopalatopharyngoplasty compared with transpalatal advancement pharyngoplasty. Laryngoscope 107:735-740, 1997 5. Sher AE, Schechtman KB, Piccirillo JF: The efficacy of surgical modifications of the upper airway in adults with obstructive sleep apnea syndrome. Sleep 19(2):156-177, 1996 6. Friedman M, Ibrahim HZ, Vidyasagar J, et al: Z-palatoplasty (ZPP): a technique for patients without tonsils. Otolaryngol Head Neck Surg 131:89-100, 2004 7. Friedman M, Ibrahim H, Joseph NJ: Staging of obstructive sleep apnea/ hypopnea syndrome: A guide to appropriate treatment. Laryngoscope 114:454-459, 2004 8. Senior BA, Rosenthal L, Lumley A, et al: Efficacy of uvulopalatopharyngoplasty in unselected patients with mild obstructive sleep apnea. Otolaryngol Head Neck Surg 123:179-182, 2000 9. Fairbanks DN: Operative techniques of uvulopalatopharyngoplasty. Ear Nose Throat J 78:846-850, 1999 10. Friedman M, Duggal P, Joseph NJ: Revision uvulopalatoplasty by Z-palatoplasty. Otolaryngol Head Neck Surg 136:638-643, 2007