Balloon Sinuplasty

Article Author:
Daniel Lofgren
Article Editor:
Carl Shermetaro
Updated:
8/30/2019 3:22:29 PM
PubMed Link:
Balloon Sinuplasty

Introduction

Since the Federal Drug Administration (FDA) approval for nasal sinus use in 2005, balloon sinuplasty (BSP) has continued to grow in popularity among otolaryngologists as a minimally invasive way to treat patients suffering from chronic rhinosinusitis (CRS).[1][2][3] The idea of using balloon dilation to open an anatomic structure is not a new concept, as cardiac surgeons have used similar techniques in coronary arteries since the late 1970s. In the late 1990s, some otolaryngologists were attempting to use 5-7 french Fogarty catheters to preserve the patency of nasal ostia.[4] This technique offers the ability to dilate sinus ostia and outflow tracts via local microfracture - without destroying the overlying mucosa and maintaining physiologic function.[3][5] The goal of BSP is to allow for improved mucociliary clearance by minimizing obstruction of the outflow tracts, thus causing symptomatic improvement in patients suffering from CRS. 

The description of chronic rhinosinusitis in the literature as the inflammation of nasal mucosa and the surrounding sinuses lasting more than 12 weeks.[1][6][7] Patients describe a myriad of symptoms including congestion, rhinorrhea, facial pressure, hyposmia, but most commonly nasal obstruction.[1][5][6] This condition's etiology is not fully understood, and multiple studies point to various causes, including biofilms, bacterial antigens, fungal infections, or immune dysfunction, among others.[3][7] The disease is currently broken down into two distinct subgroups: CRS with nasal polyposis (CRSwNP) and CRS without nasal polyposis (CRSsNP). Approximations are that over 31 million people suffer from CRS, and although medical management is the mainstay treatment in these patients, the literature notes an increasing number of surgical cases.[1][6] From 2006 to 2011, estimates were that 1 in 3.7 CRS patients underwent a sinus surgery for treatment. Upwards of 300000 patients elect for sinus surgery annually, which include BSP, functional endoscopic sinus surgery (FESS), or a mix of both called a “hybrid” procedure.[1][3][5][6]

Recently, there has been a push to perform BSP under local sedation in an in-office setting, which avoids the use of general anesthesia in patients with concomitant comorbidities and provides cost savings to the patient and the physician.[8] Holy et al. described that the ratio of sinus surgery per 100,000 patients had remained constant between 2006 and 2011, however, they did note a 7% increase in BSP only procedures during that time frame.[9] One study, which used the Center for Medicare and Medicaid Database, looked at billing codes to compare the number of specific sinus procedures performed from 2012 to 2016. The number of balloon only procedures jumped from 5603 to 25640 in that timeframe. This study found that in-office BSP served as the major reason for this jump in treatment numbers.[10] With the application of in-office BSP, concerns exist regarding the possibility of overutilization of the procedure due to its variety of proposed indications, which this activity will discuss later. In one retrospective cohort study, the authors used one of the largest commercial health insurance program’s database and noted that 86.53% of BSP procedures studied took place in an in-office setting.[1] With the recent increase in popularity of BSP procedures and the ease of availability in an in-office setting, the authors of this paper hope to provide a general overview of balloon sinuplasty for physicians, healthcare providers, and patients alike.

Anatomy

The main structures of the nasal cavity that guide localization and treatment derive from the lateral nasal wall. Through the various nasal structures, one can visualize the ostia (opening) of the paired frontal sinuses, maxillary sinuses, and sphenoid sinuses. These sinuses, along with the nasal passage, have a lining of pseudostratified ciliated columnar epithelium, which warm, humidify, and filter inhaled debris. 

The frontal sinus, located superior and anterior to the orbits, drains via the frontal sinus drainage pathway inferiorly into the ethmoid infundibulum or middle meatus depending on the attachment of the uncinate process. The uncinate process is a projection of the ethmoid bone which attaches anatomically to one of three structures. It can attach to the lamina papyracea, which separates the orbit with the nasal cavity and under this circumstance will cause the frontal sinus to drain directly into the middle meatus. The lamina papyracea is usually 0.2 to 0.4 millimeters thick and can easily suffer a fracture with excessive force. If the uncinate attaches to the skull base or the middle turbinate, the frontal sinus will drain into the ethmoid infundibulum instead.

The maxillary sinuses are on either side of the nose and inferior to the orbit. They drain via the maxillary ostia into the middle meatus via the ethmoid infundibulum.

The sphenoid sinuses, which are the most posterior of the sinuses, are located below the sella turcica of the skull base and drain into the superior meatus via the sphenoethmoidal recess. 

Indications

Since the approval of the nasal balloon device, much debate has taken place regarding the appropriate indications for the use of balloon sinuplasty. The American Academy of Otolaryngology-Head and Neck Surgery Foundation Board of Directors (AAO-HNSF) presented its most current guidelines in 2017. The main indication for balloon sinuplasty is CRSsNP refractory to medical treatment with a positive computed tomography (CT) scan of the sinuses showing mucosal thickening and obstruction. BSP may also be used as an adjunct procedure to functional endoscopic sinus surgery (FESS) in patients with CRSsNP. Other proposed indications include recurrent acute rhinosinusitis (RARS) with CT evidence of sinus disease and barosinusitis.[2][3][5][6][11]

There are currently no specific indications for the option of BSP in an office setting per the AAO-HNSF.[11] The physician usually chooses between in-office versus operating room BSP, but external factors like insurance approval, reimbursement, operating room availability, and patient comorbidities can influence this decision.[8]

Contraindications

One notable contraindication to balloon sinuplasty is CRSwNP, due to the device's mechanism of action versus the pathophysiology of the diseases. In CRSwNP, numerous polyps grow into and obstruct the nasal cavity and sinus ostia. The balloon does not alter or destroy the nasal mucosa and therefore would be unable to remove the polyp burden by itself.

BSP is indicated and effective for use in single-cell sinuses, but would not be effective within the ethmoids because they are multicell structures.

Other contraindications include but are not limited to the following[2][5][11]

  • Headache without CRS or RARS
  • Sleep apnea without RARS or CRS
  • CRS or RARS patients without CT findings or an asymptomatic patient
  • Allergic fungal sinusitis
  • Cystic fibrosis
  • Malignancy
  • Patient refusal
  • Prior skull-based dehiscence

Equipment

Equipment required for balloon sinuplasty includes but is not limited to[6]:

  • Straight or angled rigid nasal endoscope for viewing sinonasal anatomy.
  • Guide catheter - directs the tip of the device towards the intended ostia.
  • Guidewires are used to guide catheter entry into the correct sinus. It can be radiopaque when used with fluoroscopic imaging, or it can transilluminate the sinuses for external guidance
  • Balloon catheters are used to dilate the ostia physically and are inflated to certain pressures within the range 8 to 12 atmospheres.
  • The balloon inflation device is a high-pressure system used for inflation of the balloon itself.
  • An irrigation catheter serves to wash purulence or other material out of the sinus in question.

The US Food and Drug Administration has only approved two balloon sinuplasty devices to date. One device is indicated for frontal and sphenoid sinus disease in patients over 18, and maxillary sinus disease in patients under 17. The other device is indicated for the maxillary sinuses in patients two years and older, and for frontal and sphenoid sinuses in patients over 12 years old.

Personnel

Outside of the physician provider, one or more other assistants may be necessary to hold or manipulate instrumentation throughout the procedure. These assistants could consist of resident physicians, medical students, nursing staff, medical assistants, or trained office personnel. Usually, their assistance is necessary for exchanging guide catheters, flushing the device, or manipulating the balloon inflation device.

Preparation

After performing a proper history and physical along with obtaining signed informed consent, it has been recommended by the AAO-HNFS, that a CT scan of the sinuses is necessary before the procedure.[11] Obtaining a baseline quality of life (QoL) score before surgery is also a recommendation of the AAO-HNFS among others for the sake of postoperative comparison. Examples of these QoL scores include the Sino-Nasal Outcome Test (SNOT-20), the Wong-Baker FACES Pain Scale or Rhinosinusitis Symptom Inventory.[5][8][11][12][13]

The procedural steps below are the general steps leading up to the procedure. To the authors' knowledge, many variations of procedural steps and technique exist between physician providers, since there is no universal protocol for this procedure.

  • In regards to balloon sinuplasty in the setting of the operating room[3][14][15]:

The patient lies supine on the operating table for either general anesthesia or conscious sedation performed by the anesthesia team. The patient then gets draped according to physician preference in a sterile fashion. A topical nasal decongestant, most commonly oxymetazoline, is then typically applied to the affected nasal cavity to promote vasoconstriction and improve intraoperative hemostasis. Subsequently, the physician injects their preferential local anesthetic (lidocaine with or without epinephrine) into various points in the nasal anatomy, which can include the middle turbinate, inferior turbinate, or uncinate among others.

  • In regards to the preparation of balloon sinuplasty in-office[8]:

The patient remains seated in a standard office reclining exam chair. Topical nasal decongestant and nebulized anesthetic spray are then applied to the affected nasal cavity and ten minutes is allowed for local absorption. Following this, cotton pledgets soaked in lidocaine or tetracaine are applied directly to the nasal cavity and remain in place for ten more minutes. After removing the packing, the physician will inject their preferential local anesthetic (+/- epinephrine) into selected areas within the nasal mucosa.

Technique

After providing proper preparation and anesthesia, visualization via nasal endoscopy begins. Under direct endoscopic visualization, the guide catheter is inserted into the nasal cavity and visually guided into the opening of the intended ostia. The guidewire then gets extended into the appropriate sinus ostia. Either fluoroscopy or more commonly, external transillumination through the sinus cavity, confirms the guidewire placement. Upon confirmation of guidewire placement in the correct anatomical location, the balloon is advanced over the guidewire to completely penetrate the ostia. The balloon is then inflated to 8 to 2 atmospheres of pressure based on physician preference, deflated, and then reinflated a second time. Upon removal of the deflated balloon, the sinus may be rinsed with normal saline via a lavage tube in an operating room setting. Normal saline rinses are rarely used during in-office setting due to the lack of a protected airway.[2][5][8][12][15][16]

Postprocedure management of BSP does vary from provider to provider, but some general recommendations include:

  • Vision assessment and mental status exam performed by the physician
  • Saline nasal spray with a short course of nasal steroids
  • Follow up office visits with nasal endoscopy at one week, three months, and one year from the date of surgery
  • Follow up CT scan of the sinuses at 3 months to compare Lund-McKay scores
  • Postoperative quality of life scores at 3, 6, and 12 months compared with their respective preoperative quality of life scoring. These can include the Sino-Nasal Outcome Test (SNOT-20), the Wong-Baker FACES Pain Scale or Rhinosinusitis Symptom Inventory, among others.

Complications

Since its inception, balloon sinuplasty has a reputation as a safe, yet effective minimally invasive procedure. The first large scale study by Bolger et al., deemed the CLEAR study, looked at adverse events within a 24 week follow up period after balloon sinuplasty. Out of the 115 patients included in the study, there were no serious adverse effects, defined as cerebrospinal fluid leaks (CSF), diplopia, significant intraoperative bleeding, or vision loss. There were a reported nine patients diagnosed with acute bacterial sinusitis during the immediate follow-up period, which researchers attributed to the procedure.[13]

This same study population was then followed by Weiss et al. for two more years after the initial time frame. Sixty-five of the original 115 patients were enrolled due to two of the original surgical hospitals not participating. They noted no adverse events in the remaining participants in this study two years after the initial surgery.[17]

A recent retrospective cohort study from 2018 explored the complication rates of 2851 patients who underwent BSP from 2011 to 2014. They noted an overall complication rate of 5.26%, which subdivided into the three following categories: orbital (2.95%), bleeding (2.03%), and skull base injury (0.35%). The orbital complications category included the following: fractures, hemorrhage, orbital cellulitis, epiphora, pain, and erythema around the eye, ophthalmoplegia, diplopia, and orbital disorder. Skull base complications consisted of CSF leak, pneumocephalus, skull base injury, and central nervous system complications. They also noted that the complications rates dropped from 2012 to 2014.[1] It is of interest to the authors that only one case report of a postoperative CSF leak has been noted in the literature directly after a BSP-only procedure, even though 0.35% of procedures have resulted in skull base injury per one of the largest insurance databases in the United States.[18] 

Other reported complications noted in the literature include acute bacterial sinusitis and tooth/facial numbness.[8][13] Interestingly, there was one case report of an acute MI during a BSP procedure noted by Hughes et al. in a patient without cardiac history. The group hypothesized that excessive vagal stimulation occurred from instrumentation within the maxillary mucosa or the orbit, which was accidentally breached when trying to balloon the right frontal sinus ostia.[19]

Clinical Significance

Since its advent, balloon sinuplasty has become an intensely debated topic within the realm of otolaryngology. Proponents of this minimally invasive procedure note its ease of use, safety profile, cost, efficacy, and reimbursement as reasons for attempting to broaden its surgical indications. Physicians who lean away from BSP, in comparison to FESS, will list similar reasons as to why it needs to be utilized less in the field. With that in mind, the authors of this study wanted to touch on revision rates, complications, and cost-effectiveness of this procedure.

The CLEAR study(s) by Bolger et al. and Weiss et al., were considered the initial landmark papers for postoperative complications and efficacy.[13][17] In the initial study by Bolger et al., the authors looked at both balloon only procedures as well as “hybrid” procedures with the Acclarent balloon device. At twelve weeks post-op, out of the original 358 ballooned sinuses, 268 were viewed under endoscopic evaluation, which revealed patency in 212, non-patency in 6 sinuses, and indeterminant patency in 50 sinuses. At 24 weeks post-op, 247 of the sinuses were patent, 2 were non-patent, and 55 were indeterminate. Overall 80.5% of sinuses remained patent after BSP, compared with 1.5% classified as non-patent and 17.9% classified as indeterminate patency. Patients in this study also reported a significant decrease in SNOT-20 scores when compared to preoperative scores. Of the total patients treated with BSP, subjective symptom improvement was noted by 85% of patients at week one, 98% by week 12, and 80% at week 24. The authors did note that 3 of the patients in the study did require revision surgery due to irreversible or progressed non-patency, and there was a device malfunction in 12 of the 358 sinuses.[13] The second portion of the CLEAR study by Kuhn et al. looked at 202 sinus ostia from the remaining follow up patients. They noted that 172 of 202 sinus ostia (85%) were endoscopically patent, 2 of 202 (1%) were non-patent, and 28 of 202 (14%) were indeterminate. A statistically significant difference in sinus CT scores was determined as 1.95 at 1 year versus 8.89 at baseline, and 1-year SNOT-20 scores (0.91) were significantly improved from baseline (2.14).[20] The final portion of the CLEAR study analyzed aggregate data in this patient population for up to two years postoperatively. In the balloon-only patients, a statistically significant decrease in Lund-MacKay CT scores was noted decreasing from 5.67 to 1.75 two years postoperatively. Statistically significant decreases in SNOT-20 scores were noted in the balloon only group and hybrid group when compared with their respective preoperative baselines.[17]

Another landmark trial in the literature, termed The BREATHE 1 study, by Stankewitz et al., performed only balloon sinuplasty on 58 maxillary ostia with the Entellus FinESS system. They utilized CT imaging of the sinuses to look at patency rates with this new system. They found that at the three month follow up appointments, 95.8% of the ballooned maxillary sinus ostia were patent via CT imaging.[8]   

A more recent study focused on 2851 CRS patients who underwent BSP-only surgery compared with both hybrid procedures as well as FESS alone. The overall complication rate six months after surgery for BSP and FESS was 5.26% vs 7.35% respectively. The complications rate breakdown can be seen in the above section entitled “Complications”. In regards to revision rates, this study reported that 7.89% of BSP only patients underwent revision compared with FESS (16.85%) and hybrid (15.15%). It was noted that revisions of balloon only cases were almost exclusively done by FESS.[1]

Koskinen et al. focused on comparing BSP and FESS in regards to the duration of sick leave and post-operative adhesions. They found a significant difference between the median amount of sick leave in the BSP treated patients (4 days) vs. the FESS treated patients (14 Days), although they noted that “sick leave” was the estimate of recovery time made by the surgeon.[15] Another study had noted a short recovery time for patients undergoing BSP with 14 patients able to resume pretreatment activity within 1 day (47%), 13 able to return within 2 days (43%), 1 able to return in 4 days (3%) and 2 able to return in 6 days (7%). As for post-treatment pain medication, Stankiewicz reported an average duration of pain medication as 1.4+/- 1.3 days after BSP.[8]

Adhesions or synechiae within the nasal cavity have been documented post-operatively after FESS procedures, but minimal literature has noted formation after BSP. In one study, which compared SNOT-22 scores and rhinometry in uncinectomy only vs BSP, three out of thirty BSP patients developed synechia postoperatively compared to 12 of 32 in the uncinectomy group.[14] In regards to rhinometry, Bizaki et al. observed a statistically significant improvement in nasal volume and airflow after balloon sinuplasty, which was similar to uncinectomy alone.[14] Koskinen et al. observed that 8 of the 38 FESS patients had notable adhesions on physical exam compared with 0 of the 33 BSP patients. Interestingly enough, they noted no significant difference in median surgical time between FESS and BSP, and the BSP patients required almost double of local anesthetic than FESS group.[15]

The authors do note the possibility of publication bias in the literature. Four of the larger studies listed in this project were sponsored by either Acclarent or Entellus, the two main manufacturers of BSP devices. We hope that with the recent increases in BSP only procedures, more data can be used to better study the efficacy of balloon sinuplasty and allow us to reach a consensus on clinical indications for the procedure. The authors note some discrepancies within the literature concerning complications, especially in regards to skull base injury, and hope that more focus can be placed on reporting any suspected BSP related complications. It is the authors’ opinion that BSP can provide symptomatic improvement, without major complications, in the correctly selected patient population. Although there is some conflict in regards to its indications and clinical use, with its mucosal tissue sparing properties, it can serve as a great tool in the arsenal of otolaryngologists for patients suffering from chronic sinus disease.

Enhancing Healthcare Team Outcomes

Balloon sinuplasty is a minimally invasive process with a low complication rate and side effect profile. Although rare, complications of balloon sinuplasty may require intervention by other physician providers if deemed necessary by the procedural physician and team. Episodes of acute bacterial sinusitis may require the use of a pharmacist for appropriate antibiotic dosing in patients with concomitant comorbidities reducing renal or hepatic clearance.[8] Damage to the orbital wall and herniation of orbital contents into the nasal cavity may require consultation from ophthalmology in particular cases. Damage to the skull base could request a consultation to neurosurgery if not able to be controlled by otolaryngology.[1] As seen in one case report in this article, cardiology or emergency medicine may be needed if a patient develops an acute MI intraoperatively.[19] [Level V]

As mentioned earlier in the article, other health professionals need to be aware of the equipment and necessary steps, especially if they plan to assist in the procedure itself. In many offices, medical assistants, nursing staff, residents, or medical students can support the operating physician in setting up the device, preparing the patient, inflating the balloon, and providing irrigation. The assistants need to have an adequate understanding of the parts and controls of the device in cases of defective instrumentation or if the operator requests assistance. If these assistants have in-depth knowledge of the procedural steps and instrumentation, they could also act as sentinels to prevent mistakes or errors made by the operating physician and prevent complications to the patient.

Nursing will provide post-procedural care, and can coordinate again with the pharmacist if pain medications needed, and request the treating physician to prescribe as needed.  Additionally, the pharmacist can verify dosing and administration for post-operative meds such as nasal rinses, etc. Only with an interprofessional team approach, involving physicians, nurses, surgical assistants, and pharmacists to balloon sinuplasty can the likelihood of positive patient outcomes be increased. [Level V]

Nursing Actions and Interventions

  • Educate the patient and family about the disease
  • Ensure consent has been signed
  • Ensure that the correct nostril is to be operated upon
  • Ease patient anxiety
  • Monitor vital signs during and after the procedure
  • Assist the surgeon during the procedure

Nursing Monitoring

While sinuplasty is done by the surgeon, a nurse is often needed to assist during the procedure. First, the nurse has to confirm which side of the nose is being treated and document it. If any sedation is to be used, the nurse has to monitor the vital signs regularly. The patient's pain level has to be monitored. After the procedure, the patient needs to be monitored for 1-2 hours before discharge.



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