Revision Sinus Surgery

324	Michael G. Stewart and Scott M. Rickert

36

Fig. 36.4  Sinonasal outcome test

symptoms (12 in all) from the 1997 Task Force list of major and minor symptoms [5]. A total of 21 patients with a mean follow-up of 12.4 months after revision surgery were reported. The author converted raw symptom score changes into effect sizes to make interpretation easier; the effect size is a relative measure of change calculated by dividing actual change by the standard deviation of the baseline value. In this study, all symptoms improved after revision surgery. Substantial improvement was seen

in the individual symptoms of “nasal obstruction” and “hyposmia,” and moderate improvements were seen in symptoms “facial pressure,” “rhinorrhea,” “headache,” “fatigue,” and “ear pain.” When grouped into four content domains (nasal, facial, oropharyngeal, systemic), all domains showed at least moderate improvement in effect size. These improvements were statistically similar in magnitude to changes in a group of patients after primary endoscopic sinus surgery. This series also reported on

Objective and Subjective Outcomes after Revision Sinus Surgery

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Fig. 36.5  Rhinosinusitis disability index (RSDI)

326	Michael G. Stewart and Scott M. Rickert

36

Fig. 36.6  Rhinosinusitis quality of life (QOL) instrument

medication use after revision sinus surgery; use of nasal steroids, antihistamines, and antibiotics did not show statistically significant changes.

Other studies have shown significant improvement in disease-specific QOL and in frontal recess patency in patients undergoing revision frontal sinus endoscopic surgery using image guidance [9]. QOL scores were noted to be clinically as well as statistically significantly improved.

Patients with massive nasal polyposis have been reported to have a high rate of revision surgery (47%), and in one study, a history of prior sinus surgery or the presence of asthma predicted a higher rate of revision surgery [29]. Whether or not the presence of asthma pre-

dicts poorer outcome after ESS is controversial, and many studies have not found a significant association [25].

One retrospective study noted that patients with classic Samter’s triad (asthma, nasal polyposis, aspirin sensitivity) had more extensive disease on CT scan scores than patients with chronic rhinosinusitis without Samter’s triad. In addition, the Samter’s triad patients required a larger number of revision surgeries [1]. However, patients seem to benefit from improved QOL and improved control of asthma – even if repeated revision surgery is needed [20, 23]. So the presence of Samter’s triad should not deter the surgeon from pursuing revision surgery if it is indicated.

Objective and Subjective Outcomes after Revision Sinus Surgery

327

■Difficulties in assessing outcomes in patients undergoing revision sinus surgery include the lack of a control group. So, even though large improvements were identified, it is not clear that they were necessarily due to the intervention. However, given the nature of revision surgery, in particular the fact that it is usually only performed when other treatment options have been exhausted, it would be difficult to perform a study with a true control group. Therefore, uncontrolled studies might be the best evidence possible in this disease.

Conclusions

Outcomes after revision sinus surgery can be divided into subjective and objective findings. In general, patients with rhinosinusitis had significant improvements in objective outcomes such as endoscopy score, and subjective outcomes such as QOL and symptom burden, after revision sinus surgery. In fact, outcomes after revision surgery seem to be equivalent to outcomes after successful primary surgery in some cases.

The CT scan is an important indicator of the anatomic extent of disease and severity of mucosal change. However, CT findings after revision surgery are not well described, and surgical changes can modify the interpretation of anatomic findings. Therefore, symptoms and QOL might be somewhat more important as outcome measures after surgery or revision surgery. However, it is generally best to consider subjective and objective outcomes as complimentary. Researchers and clinicians should choose from a variety of outcomes tools in the evaluation of patients being considered for revision sinus surgery.

References

1.Amar YG, Frenkiel S, Sobol SE (2000) Outcome analysis of endoscopic sinus surgery for chronic sinusitis in patients having Samter’s triad. J Otolaryngol 29:7–12

6.Bhattacharyya N (2006) Radiographic stage fails to predict symptom outcomes after endoscopic sinus surgery for chronic rhinosinusitis. Laryngoscope 116:18–22

7.Bhattacharyya T, Piccirillo JF, Wippold FJ 2nd (1997) Relationship between patient-based descriptions of sinusitis and paranasal sinus computed tomographic findings. Arch Otolaryngol Head Neck Surg 123:1189–1192

8.Bradley DT, Kountakis SE (2005) Correlation between computed tomography scores and symptomatic improvement after endoscopic sinus surgery. Laryngoscope 115:466–469

9.Chiu AG, Vaughan WC (2004) Revision endoscopic frontal sinus surgery with surgical navigation. Otolaryngol Head Neck Surg 130:312–318

10.Gliklich RE, Metson R (1995) Techniques for outcomes research in chronic sinusitis. Laryngoscope 105:387–390

11.Hwang PH, Irwin SB, Griest SE, Caro JE, Nesbit GM (2003) Radiologic correlates of symptom-based diagnostic criteria for chronic rhinosinusitis. Otolaryngol Head Neck Surg 128:489–496

12.Kennedy DW, Wright ED, Goldberg AN (2000) Objective and subjective outcomes in surgery for chronic sinusitis. Laryngoscope 110:29–31

13.Kountakis SE, Bradley DT (2003) Effect of asthma on sinus computed tomography grade and symptom scores in patients undergoing revision functional endoscopic sinus surgery. Am J Rhinol 17:215–219

14.Krouse JH (2000) Computed tomography stage, allergy testing, and quality of life in patients with sinusitis. Otolaryngol Head Neck Surg 123:389–392

15.Lanza DC, Kennedy DW (1997) Adult rhinosinusitis defined. Otolaryngol Head Neck Surg 117:S1–S7

16.Ling FT, Kountakis SE (2007) Important clinical symptoms in patients undergoing functional endoscopic sinus surgery for chronic rhinosinusitis. Laryngoscope. 117(6):1090–1093

17.Lund VJ, Kennedy DW (1997) Staging for rhinosinusitis. Otolaryngol Head Neck Surg 117:S35–S40

18.Mamikoglu B, Houser SM, Corey JP (2002) An interpretation method for objective assessment of nasal congestion with acoustic rhinometry. Laryngoscope 112:926–929

2.Atlas SJ, Metson RB, Singer DE, Wu YA, Gliklich RE (2005) 19. McMains KC, Kountakis SE (2005) Revision functional

Validity of a new health-related quality of life instrument for	endoscopic sinus surgery: objective and subjective surgical
patients with chronic sinusitis. Laryngoscope 115:846–854	outcomes. Am J Rhinol 19:344–347
3. Benninger MS, Senior BA (1997) The development of the	20. McMains KC, Kountakis SE (2006) Medical and surgical
Rhinosinusitis Disability Index. Arch Otolaryngol Head	considerations in patients with Samter’s triad. Am J Rhinol
Neck Surg 123:1175–1179	20:573–576

4.Bhattacharyya N (2003) The economic burden and symp21. Meltzer EO, Hamilos DL, Hadley JA, Lanza DC, Marple BF,

tom manifestations of chronic rhinosinusitis. Am J Rhinol 17:27–32

5.Bhattacharyya N (2004) Clinical outcomes after revision endoscopic sinus surgery. Arch Otolaryngol Head Neck Surg 130:975–978

Nicklas RA, Adinoff AD, Bachert C, Borish L, Chinchilli VM, Danzig MR, Ferguson BJ, Fokkens WJ, Jenkins SG, Lund VJ, Mafee MF, Naclerio RM, Pawankar R, Ponikau JU, Schubert MS, Slavin RG, Stewart MG, Togias A, Wald ER, Winther B; The Rhinosinusitis Initiative (2006) Rhinosinusitis: developing guidance for clinical trials. Otolaryngol Head Neck Surg 135:S31–S80

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22.Piccirillo JF, Merritt MG, Richards ML (2002) Psychometric and clinimetric validity of the 20-item Sino-Nasal Outcome Test (SNOT-20). Otolaryngol Head Neck Surg 126:41–47

23.Robinson JL, Griest S, James KE, Smith TL (2007) Impact of aspirin intolerance on outcomes of sinus surgery. Laryngoscope 117:825–830

24.Smith TL, Rhee JS, Loehrl TA, Burzynski ML, Laud PW, Nattinger AB (2003) Objective testing and quality-of-life evaluation in surgical candidates with chronic rhinosinusitis. Am J Rhinol 17:351–356

25.Smith TL, Mendolia-Loffredo S, Loehrl TA, Sparapani R, Laud PW, Nattinger AB (2005) Predictive factors and outcomes in endoscopic sinus surgery for chronic rhinosinusitis. Laryngoscope 115:2199–2205

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Michael G. Stewart and Scott M. Rickert

26.Stewart MG, Donovan DT, Parke RB, Bautista MH (2000) Does the severity of sinus computed tomography findings predict outcome in chronic sinusitis? Otolaryngol Head Neck Surg 123:81–84

27. Stewart MG, Sicard MW, Piccirillo JF, Diaz-Marchan PJ (1999) Severity staging in chronic sinusitis: are CT scan findings related to patient symptoms? Am J Rhinol 13:161–167

28.Stewart MG, Smith TL (2005) Objective versus subjective outcomes assessment in rhinology. Am J Rhinol 19:529–535

29.Wynn R, Har-El G (2004) Recurrence rates after endoscopic sinus surgery for massive sinus polyposis. Laryngoscope 114:811–813

Chapter  37	37
Bioabsorbable Materials
in Revision Sinus Surgery

Rakesh K. Chandra and Robert C. Kern

 Core Messages

■A spectrum of absorbable biomaterials is available for revision endoscopic sinus surgery.

■Each of these agents has unique properties that impact on both the mode of application and mucosal healing.

■The anatomy of revision sinonasal cavities exhibits significant variability depending upon the extent of previous surgery and the healing process.

■The mucosa of patients with recalcitrant disease undergoing revision sinus surgery may exhibit significant qualitative differences compared to that of primary cases.

■Roles of absorbable biomaterials include potential impact on hemostasis as well as mucosal healing.

■Properties differ between the available products.

■A complete understanding of the unique features of available bioabsorbable agents and their tissue effects is crucial, so that the appropriate material may be selected for a particular revision surgery.

 

Introduction

A variety of individual factors may be associated with the need for revision endoscopic sinus surgery (ESS). Some of these reflect recurrence (or reexacerbation) of the underlying inflammatory disease process, such as regrowth of polyposis or localized sinus ostial obstruction secondary to mucosal edema. Other causes of primary surgical failure may be anatomic in nature, reflecting the quality of healing or retained anatomy after initial surgery. These conditions include the development of synechiae or fixed ostial stenosis. Certainly any combination of inflammatory, anatomic, and infectious etiologies may exist in any one patient. As our understanding of chronic rhinosinusitis has continued to evolve, it has also become clear that patients with recalcitrant rhinosinusitis may exhibit his-

Contents
Introduction  . . . . . . . . . . . . . . . . .	329
Classification of Absorbable Biomaterials  . . . .	.   330
Selection of Material  . . . . . . . . . . . . .	.   330
Collagen or Gelatin Based  . . . . . . . . . .	330
Hyaluronic Acid Based  . . . . . . . . . . .	.   331
Cellulose Based  . . . . . . . . . . . . . .	.   333
Additional Considerations and Future Directions  .	334

tologic and ultrastructural abnormalities including deficiencies of ciliary density, anatomy, and function [1,2,7]. Other factors may include biofilm formation [19] and osteitis of the underlying bone [14].

Our understanding of the pathophysiology of recurrent or recalcitrant sinus disease has paralleled an increase in the application of revision surgery. This, in turn, has been facilitated by continued evolution in surgical instrumentation, medical therapies, and intranasal dressings.

■Packing agents have been applied after primary and revision ESS to attain three objectives:

1.Hemostasis.

2.Stenting to support the middle turbinate in a medial position.

3.Spacers to prevent the accumulation of blood and mucus in the surgical cavity.

Ideally, absorbable biomaterials should attain these goals with optimal patient comfort. Such agents also report theoretical enhancements in postoperative mucosal healing. These are worthy objectives because conventional packing may be associated with significant patient discomfort while in place and during removal potentially leading to patient dissatisfaction and increases in oral analgesic use [13]. This fact has been established in controlled studies comparing absorbable agents to tampon packing [3].

		330			Rakesh K. Chandra and Robert C. Kern
		Other investigations have revealed that some forms of			Selection of Material
		nonabsorbable packing are associated with untoward tis-
		sue effects. One such study using a sheep model demon-
					Collagen or Gelatin Based
		strated that Neuropatties were associated with loss of up
		to 50% of the ciliated mucosal surface [23]. In contrast,			■ Main role is as a topical hemostat.
		the same group later demonstrated that foam tampons			■ Possible fibrogenic effect.
		are not associated with ineffective mucociliary function
		following removal [17].			These agents were introduced primarily for their hemo-
		Regardless of the packing method and material used,			static properties and were initially utilized in cardio-
		mucosal healing properties will vary substantially. Fur-			vascular applications. Only later were they adapted for
		thermore, recent studies have underscored that these			rhinologic surgery. The hemostatic effect of these agents
		principles are maintained when absorbable dressings are			is considered acceptable to manage mild to moderate
		utilized. The unique properties of the various available			bleeding, where the primary mechanism of action is to
		agents must therefore be understood in the context of re-			provide a matrix for platelet aggregation of fibrin depo-
		calcitrant sinus disease and the challenges encountered			sition [3,5,6,9,12]. The latter can be facilitated by addi-
		during revision ESS.			tion of thrombin solution, usually at a concentration of
		The goal of the present chapter is to present a frame-			1000 U/ml. Although this class of materials does have
		work for rational selection and application of absorbable			significant value in otolaryngology and ESS, known ef-
37		biomaterials.			fects on mucosal healing must be examined.
					Gelfoam and Gelfilm were both widely utilized in
					middle-ear applications prior to adaptation to ESS. The
					first report to illustrate that absorbable biomaterials were
		Classification of Absorbable Biomaterials
					not inert was published in 1997, where Tom et al. assessed
		Absorbable materials may be classified according to mo-			healing in cavities managed with and without Gelfilm
		lecular composition, which significantly affects the bio-			in a population of children who underwent a planned
		logical properties.			second-look 2–3 weeks after ESS [26]. In this investiga-
		■ Classification of absorbable biomaterials used in sinus			tion, Gelfilm was associated with adverse healing with
					increased granulation tissue. Gelfoam appears to have
		surgery:			more benign effects on the healing of sinonasal mucosa,
		1.	Collagen/gelatin based:		at least when compared to FloSeal. Randomized prospec-
			a. Gelfoam – sponge composed of porcine colla-		tive evaluation comparing these agents revealed that the
			gen.		latter was associated with greater prevalence of granula-
			b. Gelfilm – sheet composed of porcine collagen.		tion tissue and adhesions at 6–8 weeks postoperatively
			c. SurgiFlo – microfibrillar porcine collagen pre-		[5]. These findings must, however, be interpreted in the
			pared with saline or thrombin to create an in-		context of additional studies suggesting that crusting and
			jectable paste.		synechiae were no different at a 1- to 3-month follow-up
			d. FloSeal – bovine-derived gelatin matrix prepared		when FloSeal is compared to an unpacked control [12].
			with thrombin to create an injectable paste.		Nonetheless, long-term evaluation of the FloSeal ver-
			e. Avitene – microfibrillar bovine collagen pow-		sus Gelfoam cohort at 2 years postoperatively demon-
			der prepared with saline or thrombin to create a		strated that FloSeal was associated with greater preva-
			slurry or injectable paste.		lence of adhesions and an increased incidence of the
		2.	Hyaluronic acid based:		need to surgically remove adhesions [6]. These observa-
			a. SepraPack – wafer composed of hyaluronic acid		tions suggest that collagen-based hemostats, particularly
			carboxymethyl cellulose.		FloSeal, may function as a scaffold for in-growth of gran-
			b. Sepragel – hyaluronic acid carboxymethyl cel-		ulation tissue and eventually scar. Foreign material has
			lulose injectable gel.		been noted to incorporate into healing mucosa [5,6,16].
			c. Merogel – hyaluronic acid ester fabric.		It should be noted that in this series of studies, the ab-
			d. Merogel injectable – hyaluronic acid ester in-		sorbable hemostatic material was left in place filling the
			jectable gel.		sinus cavity, even after cessation of bleeding (Fig. 37.1).
		3.	Cellulose based:		This contradicts the initial descriptions for use of these
			a. Surgicel – oxidized cellulose fabric.		agents, where removal of excess product was advocated
			b. Sinu-Knit – carboxymethyl cellulose fabric.		after achieving hemostasis.
			c. Sinu-Foam – carboxymethyl cellulose inject-		The role for these agents appears to be for use as a
			able.		topical hemostat rather than as a surgical stent. Although

Bioabsorbable Materials in Revision Sinus Surgery

331

Fig. 37.1  Ethmoid cavity filled with FloSeal. Note the particulate nature of the material, which has the consistency of a paste. Leaving the cavity in this manner may predispose to adhesions

studies have introduced the possibility of adverse healing, the hemostatic role may be of significant value in scenarios encountered during revision surgery. First, it may be advisable to limit the application of cautery in

revision surgery, as thermal effects are destructive to the ciliated mucosal surface. Such treatment potentially impairs recovery of optimal mucociliary clearance in this difficult patient population. Second, revision surgery often includes dissection and exposure of the skull base and regions near the orbital apex, such as the sphenoid and posterior ethmoid region. Use of cautery may be inadvisable in these anatomic sites given their proximity to intracranial structures and the optic nerve. In these situations, an absorbable hemostatic agent should be applied precisely to the bleeding focus (Fig. 37.2), and the excess should be suctioned or irrigated from the cavity following attainment of hemostasis. Leaving the material in situ (as shown in Fig. 37.1) potentially results in significant fibrin accumulation within 1 week postoperatively (Fig. 37.3), potentially leading to meatal stenosis.

Hyaluronic Acid Based

■Associated with adequate hemostasis.

■Some preparations may augment optimal healing.

■Composition affects healing properties.

Active research is ongoing for an absorbable biomaterial with ideal properties of simultaneously providing hemostasis and functioning as a stent to support the middle

Fig. 37.2  Focal application of SurgiFlo to a bleeding focus in the region of the sphenopalatine artery. The excess material should be suctioned or irrigated from the cavity after cessation of bleeding

Fig. 37.3  One week postoperatively following filling of the ethmoid cavity with FloSeal for stenting of the middle meatus (as shown in Fig. 37.1). The middle turbinate has lateralized with significant fibrin deposition and early adhesions within the ethmoid cavity, requiring extensive debridement

	332
	turbinate while occluding the ethmoid cavity to prevent
	accumulation of blood and mucus, thus avoiding the pro-
	motion of fibrosis. Recent trends have included the use
	of materials based on hyaluronic acid, or hyaluronan, a
	glycosaminoglycan found in the extracellular milieu.
	Physiologically, this molecule interacts with water to give
	viscosity to extracellular fluids and has cellular effects in
	epithelial proliferation and possibly immune regulation.
	Hyaluronic acid has been implicated in the nearly scarless
	healing observed in fetal wounds [15]. Polymers of hyal-
	uronic acid were initially utilized to prevent adhesions in
	abdominopelvic surgery [4]. Because of these properties,
	preparations have been subsequently developed for use
	in sinonasal surgery (Fig. 37.4), but most of the research
	studying the biologic effects of this molecule have been in
	abdominal models.
	Unlike collagen-based materials (FloSeal, Surgiflo,
	Avitene), hyaluronic acid is not a vigorous promoter of
37	coagulation, and in fact, it has even been utilized in car-

Rakesh K. Chandra and Robert C. Kern

diovascular applications to reduce platelet adhesion [10]. In ESS, hyaluronic-acid-based biomaterials have been associated with adequate hemostatic effects [8], but it remains to be elucidated whether this is secondary to a tamponade effect or an effect on the coagulation system. In any case, the use of packing in ESS simply for hemostasis is controversial. Thus, the larger issue regards the influence of hyaluronic-acid-based materials on wound healing.

Hyaluronic acid was first associated with reduction of adhesions in peritoneal applications, where animal studies suggested that the primary effect is due to its function as a barrier that attracts water [25]. This evidence provided justification for the use of this material in sinonasal applications, where additional studies have investigated the influence of hyaluronic acid on the biology of wound healing in respiratory mucosa. Early data from animal models has suggested that the composition of hyaluronic acid does have a significant effect on healing. Proctor et

Fig. 37.4  Hyaluronic acid ester rolled fabric (a) and carboxymethyl cellulose wafer (b) each revealing change in consistency to a gel-like form when hydrated. When hydrated in situ, the carboxymethyl cellulose wafer takes on a gel-like consistency that coats mucosal surfaces (c)

Bioabsorbable Materials in Revision Sinus Surgery

al. [20] demonstrated in a rabbit model that woven hyaluronic acid ester (Merogel) is associated with increased foamy macrophages, granulation tissue, and ostial stenosis when compared to cross-linked hyaluronic acid gel or hyaluronic acid conjugated with mitomycin C. The latter two preparations exhibited greater ostial diameter than untreated controls. In this investigation, biomaterials were applied following creation of an antrostomy with a 4-mm otologic drill. Another rabbit model, where the maxillary sinus was stripped of its mucosa, also revealed that the woven hyaluronic acid ester was associated with incorporation into regenerating mucosa [16].

Sheep models have suggested that hyaluronic acid ester may augment epithelialization of experimentally induced mucosal wounds in healthy sheep, when examined 12 weeks postinjury [17]. This material, however, had no beneficial influence on promotion of reepithelialization or reduction of synechiae in these animal models [22]. The same group investigated a preparation of hyaluronic acid impregnated with insulin-like growth factor 1 (IGF- 1) in a sheep model, where improved reepithelialization was observed in healthy sheep. However, this composite material actually had an adverse effect on ciliary regeneration in wounds of sheep with chronic rhinosinusitis [21]. This series of animal studies demonstrates that mucosal healing after ESS is affected not only by the biomaterial that is applied, but also by the underlying inflammatory state.

Wormald et al. explored the effects of hyaluronic acid ester on mucosal healing in patients with chronic rhinosinusitis undergoing ESS [28]. No influence was observed on synechiae or mucosal edema when comparing treated and unpacked cavities. Others have compared tissue healing between hyaluronic acid ester and a nonabsorbable tampon, where no significant differences were discovered [18]. It should be noted, however, that need for lysis of adhesions during the 8-week study period was less in the latter group (8% vs. 14%), although the difference did not reach statistical significance.

There are fewer available studies investigating hyaluronic acid carboxymethyl cellulose preparations (Sepragel, SepraPack) in animal models. Ongoing work from our group utilizing a rabbit model (unpublished data) compared mucosal regeneration after maxillary sinus stripping in sinuses packed with hyaluronic acid carboxymethyl cellulose to those packed with hyaluronic acid ester. Blinded evaluation by a pathologist revealed more untoward healing characteristics in the latter group. In contrast, regenerated mucosa in the hyaluronic acid carboxymethyl cellulose group was similar to unstripped mucosa and to unpacked controls.

Initial studies using hyaluronic acid carboxymethyl cellulose gel (Sepragel) compared to an untreated control in patients undergoing ESS revealed that the former is associated with reduction of synechiae. This study however,

333

included only ten patients with a short follow-up. A randomized controlled multicenter trial [27] comparing hyaluronic acid carboxymethyl cellulose wafer (SepraPack) to no packing in 53 patients followed over 8 weeks suggested that SepraPack was associated with significantly less synechiae at 2 weeks. A trend was also observed toward decreased synechiae at 8 weeks, although this did not reach significance. This study also demonstrated improved patient comfort with the biomaterial, as patients reported significantly less congestion in experimental sides at 4 and 8 weeks postoperatively. This is an interesting finding given that patients were blinded to which was the experimental versus control side.

Although there was no difference in final cavity status between packed and unpacked sides, this data suggests that hyaluronic acid carboxymethyl cellulose wafer is associated with more favorable postoperative recovery secondary to decreased congestive symptoms and less need for aggressive debridement. Overall, studies of hyaluronic acid carboxymethyl cellulose materials support the principle that composition of hyaluronic acid has a measurable impact on the quality of healing after ESS. Use of this material should be considered in patients where significant postoperative hemorrhage is not a concern, but the patient would benefit from an agent to support the middle turbinate, particularly in those who exhibit significant apprehension about nonabsorbable packing from untoward experiences during previous procedures.

Cellulose Based

■Adequate hemostatic effect.

■Paucity of data regarding tissue healing characteristics.

The use of Surgicel in multiple surgical applications is well known where the primary role has been to augment hemostasis, particularly around vascular anastomoses. In otolaryngology, Surgicel is commonly used in the management of epistaxis, and data has also demonstrated that this agent is associated with improved comfort compared to tampon packing after ESS [24]. In that study, patients described less discomfort while the packing material was in place and during removal; in addition, the use of Surgicel was associated with less bleeding upon removal. Subsequently, other cellulose-based materials (Surgicel, Sinu-Knit, Sinu-Foam) have been released specifically for sinonasal application. A possible advantage of cellulosebased fabrics (Surgicel, Sinu-Knit) is that these agents are less likely to disturb a clot during pack removal, as is often observed when a sponge tampon is utilized. Unfortunately, there is a paucity of data examining the efficacy of these agents in mucosal healing after ESS when left in situ. Given that these materials promote platelet