Medical Policy

Subject:Devices for Maintaining Sinus Ostial Patency Following Sinus Surgery
Policy #:  SURG.00132Current Effective Date:  10/14/2014
Status:ReviewedLast Review Date:  08/14/2014


This document addresses devices placed within the sinuses for the purpose of maintaining sinus ostial patency following functional endoscopic sinus surgery (FESS) (for example, Propel™ sinus implant and the Relieva Stratus™ MicroFlow Spacer).  

Position Statement

Investigational and Not Medically Necessary:

The use of devices for maintaining sinus ostial patency following sinus surgery is considered investigational and not medically necessary for all indications.


Sinus surgery is commonly used for the treatment of individuals with chronic rhinosinusitis, infection and polyposis.  FESS is intended to open closed sinus ostia to allow proper drainage and air flow and prevent recurrent sinus infections.  Inflammation, polyp recurrence, stenosis of the surgically enlarged sinus ostia, adhesions and middle turbinate lateralization (adhesion of the middle turbinate to the lateral nasal wall) represent suboptimal outcomes following sinus surgery and lead to increased rates of revision.  Middle turbinate lateralization may cause obstruction of the middle meatus and result in recurrent infection of the maxillary, ethmoid, or frontal sinuses (Otto, 2010).  Several devices have been proposed that are designed to help maintain sinus ostial patency by reducing scarring and synechiae formation following FESS.  These include stents, packing, sponges, and gels. 

One such device is the Propel™ sinus implant. This device is a bioabsorbable drug eluting stent that is implanted into the sinus ostia following FESS and is designed to release the corticosteroid mometasone furoate over a period of several weeks as the stent itself is slowly resorbed.  It is proposed that this stent has the potential to improve surgical results by stabilizing the middle turbinate, preventing obstruction by adhesions and reducing edema.  It is designed to deliver corticosteroid to the surgical cavity with minimal potential for drug-related complications known to occur with systemic steroids and lessen the need for revision surgery to lyse adhesions.  At this time, there are three peer-reviewed published clinical trials addressing the use of this device.  These papers describe the three trials presented to the FDA during the pre-market approval (PMA) process.  These studies are known as the ADVANCE, CONSENSUS II and the ADVANCE II trials.  The latter two are randomized intra-patient controlled trials, while the ADVANCE trial was a case series. 

The CONSENSUS II study, described in the article by Murr and colleagues (2011), was the first clinical trial to evaluate the safety and effectiveness of the Propel device in humans.  CONSENSUS II was a small, randomized, double-blind, four-center pilot study.  The objective of the study was to assess the safety, effectiveness, and performance of the Propel device when used following FESS in subjects with chronic ethmoid rhinosinusitis.  Subjects studied were adults with a diagnosis of chronic rhinosinusitis with or without nasal polyps scheduled to undergo primary (bilateral ethmoidectomy with middle meatal antrostomy) or revision FESS.  However, concurrent septoplasty and surgical treatment of other paranasal sinuses was also permitted. 

In the Consensus II feasibility trial, a total of 43 subjects received a 23 mm Propel sinus implant while 7 received a shorter version.  The study used an intra-patient control design to compare the safety and efficacy of the drug eluting Propel sinus implant to a non-drug eluting control version of the implant in the contra lateral ethmoid sinus ostium.  As a result, both ethmoid sinuses received the Propel stent's scaffolding function.  Implant delivery was judged successful in 100% of the subjects and there was a statistically significant difference in reduction of ethmoid sinus inflammation postoperatively (endoscopic visual analog scale) at days 21-45 (p≤0.003).  Also reported were statistically significant reductions in the frequency of polyp formation and adhesions in the treatment arm.  Although a reduced frequency of middle turbinate lateralization was seen on the drug-eluting stent side, the difference was not statistically significant.  No device-related adverse events were reported, and eluted steroid was not detectable systemically and no evidence of adrenal suppression was found.

The ADVANCE study, described in the article by Forwith et al. (2011), was an open label prospective case series involving 50 subjects with either single or bilateral ethmoid sinus disease requiring FESS at seven study centers.  The study allowed bilateral or unilateral steroid-eluting implant placement.  Oral and topical steroids were withheld for 60 days postoperatively.  Follow-up assessments occurred prior to hospital discharge or clinic release and at days 7, 14, 21, 30 and 60 post procedure.  An additional final visit occurred at 6 months, but only a subject questionnaire was collected.  Forty-nine of the 50 subjects completed the study through 60 days, representing a follow-up rate of 98%, and 45 subjects (90%) completed follow-up through 6 months.  Endoscopic follow-up was performed to 60 days post-operatively and self-reported outcomes using three scales (Sinonasal Outcomes Test 22, Rhinosinusitis Disability Index, and Total Nasal Symptom Scoring) were followed to 6 months.  Implants were successfully placed in all 90 sinuses.  At 1 month, polypoid edema was 10.0%, significant adhesions 1.1%, and middle turbinate lateralization 4.4%.  These results compared favorably with historic controls using other methods:  19% incidence of post-operative lysis of adhesions using absorbable hyaluronic acid packing (Miller, 2003) and 6% incidence of adhesions using nonabsorbable silastic sheets following FESS (Lee, 2007).  Favorable mean changes from baseline to day 60 and 6 months in the three self-reported surveys were statistically significant.

The ADVANCE II  study, described by Marple and colleagues (2012), was a prospective, randomized, double-blind, intra-patient controlled, multi-center study that enrolled 105 subjects at 11 US sites evaluating the safety and effectiveness of the Propel device following bilateral ethmoidectomy for chronic rhinosinusitis.  Subjects were randomized to receive the Propel device in one ethmoid sinus and a non-drug eluting stent device identical in structure and appearance to the Propel device in the contralateral ethmoid sinus.  This methodology assisted in the blind nature of the study.  The primary effectiveness endpoint was reduction in post-operative interventions.  The primary safety endpoint was ocular safety defined as absence of clinically significant sustained elevation (≤10 mm Hg) in intraocular pressure through day 90.  The primary efficacy endpoint was the reduction in need for post-operative interventions at day 30, as determined from video-endoscopies reviewed by a panel of three independently blinded sinus surgeons.  Implants were successfully deployed in all 210 ethmoid sinuses.

Follow-up assessments occurred prior to hospital discharge or clinic release and at post-operative days 14, 30, 60 and 90 post procedure.  One hundred two subjects completed the follow-up visits through 90 days, representing a follow-up rate of 97.1%. One hundred three of the 105 subjects completed the ocular follow-up visits through 90 days (98.0%).  No subject required termination from the study due to an adverse event.  The primary safety endpoint was met.  There were no clinically significant elevations in intraocular pressure and no clinically significant changes in lens opacities through day 90.  Recurrent sinusitis was the most frequently reported adverse event type, reported in 34 of the 105 subjects (32.4%).  Sinusitis was the only event type localized by sinus side; this was possible in 14 of the events.  Six occurred on treatment sides and 8 occurred on the control sides.  Two of the adverse events (sinusitis) were determined to be related to the study device.  Both resolved without sequelae.  There were no serious adverse events reported in the study.  Compared with control sinuses with non-drug eluting implants, the drug-eluting implant provided a 29% (23 vs. 33) relative reduction (p=0.028) in postoperative interventions (composite of either surgical adhesion lysis and/or oral steroids).  The reduction in postoperative interventions was driven largely by the reduction in lysis of adhesions.  The rate of adhesion lysis was reduced by 52% (p=0.005), and while the need for oral steroids was reduced by 29% this difference did not reach statistical significance.  The relative reduction in frank polyposis was 44.9% (16 vs. 29; p=0.002).

While the results of the two controlled studies are promising, they were limited to small, heterogeneous populations with short follow-up.  In addition, the studies were conducted in a setting where both sinuses had implants, 1 with steroid and the other without.  The two comparative trials described above did not compare the post operative outcomes using this device with outcomes following standard FESS without an ostial implant but with topical steroid sprays, saline irrigation, debridement, and conventional postoperative packing.   

Another device proposed for maintaining the patency of sinus ostia for up to 14 days postoperatively following sinus surgery is the Relieva Stratus™ MicroFlow Spacer (Frontal) or the Relieva Stratus™ MicroFlow Spacer (Ethmoid).  These devices are placed endoscopically with fluoroscopy and manually removed during an office follow-up visit.  These devices received FDA 510 market clearance in 2009.  Both systems are catheter-based, self-retaining implantable devices with a porous reservoir for moistening the sinuses following surgery.  Under study is a MicroFlow Spacer drug-eluting stent containing triamcinolone (Catalano, 2011).  At this time, there is insufficient evidence from controlled clinical trials to establish the safety and efficacy of these devices.  It should be noted that the FDA Manufacturer and User Facility Device Experience (MAUDE) database contains several reports regarding complications following implantation of the Stratus MicroFlow Spacer device.  A significant reported complication due to this device involves the misplacement of the device in the ethmoid sinus resulting in penetration of the orbital space requiring surgical removal of the device as well as the surrounding tissue.  With such serious complications possible, well designed and conducted trials evaluating the use of these devices are warranted.


The Propel sinus implant is a bioabsorbable drug eluting sinus stent designed to maintain patency of the ethmoid sinus ostia following FESS for chronic rhinosinusitis.  It is manufactured from a synthetic bioabsorbable copolymer, poly (L-lactide-co-glycolide, PLG) and impregnated with mometasone furoate, a synthetic corticosteroid with anti-inflammatory activity.  The device is designed to be bioabsorbed over a period of 30-45 days.  During that period, the Propel device is proposed to maintain sinus patency by reducing inflammation, significant polyp formation, adhesions, and edema in individuals 18 years of age and older. 

The device is implanted into the ethmoid sinus ostia by a physician under endoscopic visualization.  The physician uses a proprietary endoscopic delivery system to position and insert the Propel device in the desired location.  Upon insertion, the implant expands radially to conform to the surgically enlarged sinus ostium following FESS.  Once the stent is in place, the mometasone furoate is released to the local area surrounding the stent.  The Propel device was approved by the FDA as a combination product on August 11, 2011.

The Stratus Microflow Spacer is a device designed to provide slow release of fluid into the sinuses over a period of 2 weeks with the intention of maintaining sinus ostial patency.  This device may be used in either the frontal or ethmoid sinuses.  However, the manner in which it is deployed for these locations is significantly different. 

For the frontal sinus, the device is inserted into the sinus ostia and then filled with saline.  The center of the device is a fluid reservoir and the outer section is an angioplasty-like balloon with laser drilled micropores that allow the fluid to weep out over a period of 2 weeks.  The device does not completely fill the ostial lumen, which allows sinus drainage around the device.  The Stratus Microflow Spacer is held in place with plastic "retention wings" that deploy once the device in place.  For the ethmoid sinus, the device is inserted through the wall of the ethmoid sinus, not into the ostia.  This involves the use of a special device to pierce the sinus wall to allow implantation of the spacer.  When used in either the frontal sinus or the ethmoid sinus, the device is intended to remain in place for 2 weeks and then is removed in the doctor's office.


The following codes for treatments and procedures applicable to this document are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member. 

When services are Investigational and Not Medically Necessary:
When the code describes a procedure indicated in the Position Statement section as investigational and not medically necessary. 

31299Unlisted procedure, accessory sinuses [when specified as insertion of a sinus stent or spacer]
L8699Prosthetic implant, not otherwise specified [when specified as sinus stent or spacer implant]
S1090Mometasone furoate sinus implant, 370 micrograms [Propel sinus implant]
ICD-9 Diagnosis[For dates of service prior to 10/01/2015]
 All diagnoses
ICD-10 Diagnosis[For dates of service on or after 10/01/2015]
 All diagnoses

Peer Reviewed Publications: 

  1. Catalano PJ, Thong M, Weiss R, Rimash T. The MicroFlow Spacer: A drug-eluting stent for the ethmoid sinus. Indian J Otolaryngol Head Neck Surg. 2011; 63(3):279-284.
  2. Forwith KD, Chandra RK, Yun PT, et al. ADVANCE: a multisite trial of bioabsorbable steroid-eluting sinus implants. Laryngoscope. 2011; 121(11):2473-2480.
  3. Han JK, Marple BF, Smith TL, et al. Effect of steroid-releasing sinus implants on postoperative medical and surgical interventions: an efficacy meta-analysis. Int Forum Allergy Rhinol. 2012; 2(4):271-279.
  4. Lee JY, Lee SW. Preventing lateral syncechia formation after endoscopic sinus surgery with a silastic sheet.  Arch Otolaryngol Head Neck Surg. 2007; 133(8):776-779.
  5. Marple BF, Smith TL, Han JK, et al. Advance II: a prospective, randomized study assessing safety and efficacy of bioabsorbable steroid-releasing sinus implants. Otolaryngol Head Neck Surg. 2012; 146(6):1004-1011.
  6. Miller RS, Steward DL, Tami TA, et al.  The clinical effects of hyaluronic acid ester nasal dressing (Merogel) on intranasal wound healing after functional endoscopic sinus surgery. Otoloaryngol Head Neck Surg. 2003; 128(6):862-869.
  7. Murr AH, Smith TL, Hwang PH, et al. Safety and efficacy of a novel bioabsorbable, steroid-eluting sinus stent.  Int Forum Allergy Rhinol. 2011; 1(1):23-32.
  8. Otto KJ, DelGaudio JM. Operative findings in the frontal recess at time of revision surgery. Am J Otolaryngol. 2010; 31(3):175-180.

Government Agency, Medical Society, and Other Authoritative Publications: 

  1. American Academy of Otolaryngology-Head and Neck Surgery. Clinical Indicators: Endoscopic Sinus Surgery, Pediatric. 2012. Available at: Accessed on June 3, 2014.
  2. American Academy of Otolaryngology-Head and Neck Surgery. Clinical Indicators: Endoscopic Sinus Surgery, Adult. 2012. Available at: Accessed on June 3, 2014.
  3. U.S. Food and Drug Administration MAUDE - Manufacturer and User Facility Device Experience Database. Available at:  Accessed on June 3, 2014.

Propel sinus implant
Relieva Stratus MicroFlow Spacer

The use of specific product names is illustrative only.  It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.

Document History




Reviewed08/14/2014Medical Policy and Technology Assessment Committee (MPTAC) review. No change to position statement.  Updated Reference section.
Reviewed08/08/2013MPTAC review. No change to position statement.  Updated Reference section.
New08/09/2012MPTAC review.  Initial document development.