Paranasal sinuses are cavities within the skull that lead into the nose and are lined with the same type of membranes that line the inside of the nose. When one or more of the sinus cavities are inflamed and the sinuses cannot drain properly, a condition known as rhinosinusitis develops. Sinusitis often results in an infection that can be bacterial, fungal, or viral, and that can be caused by inflammation and allergies.
Chronic rhinosinusitis may persist for three months or longer. Symptoms may include nasal congestion, facial pain, headache, fever, general malaise, purulent nasal discharge, increased sensation of facial fullness on bending over, or aching teeth. Medical management remains the primary treatment option for chronic rhinosinusitis. This typically includes various oral and topical agents such as antibiotics, steroids, antihistamines, leukotriene receptor antagonists, saline irrigations, and mucolytics.
To quantify the severity of chronic sinusitis and to assess treatment response, various outcomes measures can be used, including radiologic scores, participant-reported quality of life (QOL) measures, and endoscopic grading. The Lind-McKay scoring system uses radiologist-rated information derived from computed tomography (CT) scans regrading opacification of the sinus cavities, generating a score from 0-12. Several disease-specific participant-reported QOL scores have been used. Commonly used is the Sino-Nasal Outcome Test-20 (SNOT-20) which is a validated questionnaire in which individuals complete 20 symptom questions on a categorical scale (0 [no bother] to 5 [worst symptoms can be]). Average ranking can be reported over all 20 symptoms, as well as by four subclassified symptom domains. The SNOT-22 is a variation of the SNOT-20 which includes two additional questions of nasal obstruction and loss of smell and taste. The minimal clinically important difference for the SNOT-22 has been estimated to be 8.9 points. In addition, QOL may be reported based on overall health-related QOL score, such as the Short Form Health Survey-36. The health survey consists of eight scales scores on various health domains, which are transformed into a 0-100 scale.
The natural history of the disorder includes resolution with medical therapy or no therapy in a large proportion of individuals. However, if aggressive medical management does not improve symptoms, surgical drainage of the sinuses may be necessary. Functional Endoscopic Sinus Surgery (FESS) has become important in the surgical management of chronic rhinosinusitis. A nasal endoscope is used to visualize the sinuses. Inflamed tissue and bone are removed and any obstruction found in the sinus ostia is corrected. This restores patency allowing mucous transport through the natural ostium, removes diseased tissue, and also improves access for topical therapy.
Balloon catheter dilation of sinus ostia, or balloon ostial dilation (BOD), has been used as an adjunct to FESS. Compared with FESS, where the tissue and bone are removed, the balloon compresses the mucosa and causes microfracture of the underlying bone (Ahmed et al. 2011). Additionally, it has been investigated as a stand-alone procedure as an alternative to FESS. Unlike most endoscopic sinus surgery, which requires tissue reduction (such as inferior turbinate reduction), in the BOD procedure, a device such as the Relieva® Sinus Balloon Inflation Device (Acclarent®, Inc.; Menlo Park, CA) or the Relieva® Sinus Balloon Dilation Catheter (ExploraMed® NCI, Inc.; Mountain View, CA) is used to stretch and open the sinus ostia to improve sinus drainage.
There is a growing body of published literature and/or clinical studies regarding BOD as a stand-alone procedure. The published literature consists of randomized control trials, non-comparative studies, and meta-analyses. The long-term safety and efficacy of BOD is emerging. Randomized studies on the need for subsequent revision may still exists, but the safety and efficacy of BOD has now been established.
Minni et al. (2018) published a prospective, multicenter randomized study, which evaluated the validity and safety of balloon catheter dilation (BCD), or BOD, compared to ESS in symptomatic chronic rhinosinusitis (CRS) in the frontal sinus. This trial randomized 102 individuals (64 men and 38 women; 148 frontal sinuses) with non-polypoid CRS at three hospitals. In post-procedure analyses, the researchers reviewed both radiological (Lund-McKay CT scoring modified by Zinreich) and symptomatic results (SNOT-20 questionnaire). The authors divided the affected persons into two groups. One group had light/mild frontal CRS and the other with moderate/severe frontal CRS, based on radiological findings. Each group was then divided in two smaller subgroups, in one arm the investigators used BOD and in the other they used traditional ESS. The current literature does not support the suggestion that indications for BOD and ESS are identical, and additional research is needed to determine the role for BOD in specific participant populations. The results showed a not statistically significant difference between BOD and conventional ESS of the frontal sinus in individuals with light/mild CRS and in individuals with moderate/severe CRS based on Lund-Mackay modified by Zinreich scores. Similar not statistically significant difference was observed comparing the results of SNOT-20 questionnaire in the group of light/mild frontal CRS. However,researchers noticed a statistically significant better outcome of SNOT-20 score in individuals with moderate/severe CRS who underwent BOD of frontal sinus compared to ESS. The authors concluded that BOD and ESS are both potential treatments as both therapies presented similar outcomes, safety and effectiveness for the population of light/mild and moderate/severe CRS of the frontal sinus. The study resulted in statistically significant better outcome of SNOT-20 score in individuals who underwent BOD of the frontal sinus for a moderate/severe CRS, compared to those who underwent a traditional ESS.
Soler et al. (2017) performed a prospective, multicenter, single-arm study, investigating the effectiveness of BOD in children with CRS who had failed medical management and were followed up to six months post procedure. Across four centers, 50 children were treated (aged 2 to 21 years), 33 of which were between the ages of 2 and 12 years old and the remaining 17 individuals were older than 12 to 21 years. A total of 157 BOD procedures were attempted on 98 maxillary, 30 frontal, and 29 sphenoid sinuses. The authors report all procedures were successful with no complications. At six-months post-operation, significant improvement from baseline scores in the Sinus and Nasal Quality of Life Survey (SN-5) were observed for all children (4.6 ± 1.2 versus 1.7 ± 0.8; p < 0.0001) and based on the SN-5, 92 percent of participants improved by at least 1.0 or more. Children aged 2 to 12 years with stand-alone BOD also showed significant SN-5 improvements between baseline and follow-up (4.5 ± 1.0 versus 1.9 ± 0.8; p < 0.0001). For adolescents, overall SNOT-22 mean scores were significantly improved at six months (42.2 ± 19.2 versus 10.4 ± 9.7; p < 0.0001). The authors concluded that BOD was safe and effective for children with CRS as young as two years and older.
In a meta-analysis, Xu et al. (2017) evaluated the post-operative clinical effects of balloon sinuplasty, or BOD, on CRS. Published trials were searched and prospective control studies were selected for CRS treated by BOD up through March 2017. Lund-Mackay and SNOT-20 scores were used as the primary outcomes of interest, and the methodological quality of the studies was assessed. The authors included seven prospective pre-post self-controlled studies, and the overall quality was determined to be relatively high. Meta-analysis showed that the Lund-Mackay scores at six months post operation, the SNOT-20 scores at six months and more than one year post operation were significantly lower than baseline for BOD. SNOT-20 scores at more than one year post operation were lower than baseline when a stand-alone BOD was performed. All the results were reported to be statistically significant (p < 0.05). The authors concluded that the post-operative effect of BOD on CRS was demonstrated, and the self-reported symptoms in participants were effectively relieved.
The 2017 American Academy of Otolaryngology - Head and Neck Surgery's (AAO-HNS) position statement on “Dilation of sinuses, any method (e.g., balloon, etc.)” stated that sinus ostial dilation (e.g., BOD) is a therapeutic option for selected individuals with CRS who have failed appropriate medical therapy. Clinical diagnosis of CRS should be based on symptoms of sinusitis and supported by nasal endoscopy documenting sinonasal abnormality or mucosal thickening on CT of the paranasal sinuses. This approach may be used alone to dilate an obstructed sinus ostium (frontal, maxillary, or sphenoid) or in conjunction with other instruments.
Bikhazi et al. (2014) published results from a prospective, multicenter, randomized trial performed to evaluate and compare one-year outcomes from the Randomized Evaluation of Maxillary Antrostomy Versus Ostial Dilation Efficacy Through Long-Term Follow-Up (REMODEL) study. The study compared office-based BOD and FESS, and expanded on the six-months study findings previously reported by Cutler et al. (2013). Ninety-two adults with maxillary CRS, including those with anterior ethmoid disease, who failed medical management and were surgical candidates for FESS, underwent either stand-alone BOD or FESS (50 BOD; 42 FESS) in a 1-to-1 randomization scheme. They were followed for a minimum of one year. Sinonasal symptom improvement was assessed using the SNOT-20 survey. Standardized effect sizes were computed to further assess clinical significance. Also compared between the two groups were ostial patency rate; rhinosinusitis episode frequency; impact of sinus disease on activity and work productivity (using the validated Work Productivity and Activity Impairment Survey); complications; and revision rate. Eighty-nine participants (96.7 percent) completed one-year follow-up. Both groups showed improvement in mean overall SNOT-20 scores and in all four SNOT-20 subscales. The one-year mean change in SNOT-20 after BOD (-1.64) was noninferior to FESS (-1.65; p < 0.001). The standardized effect size was large, showing improvement for both interventions. Ostial patency was 96.7 percent and 98.7 percent after BOD and FESS, respectively, and each group reported reductions (p < 0.0001) in rhinosinusitis episodes (mean decrease, 4.2 for BOD and 3.5 for FESS). Overall work productivity and daily activity impairment due to chronic sinusitis were improved (p < 0.001) in both groups. There were no complications. Revision surgery rate was two percent in each arm through one year. Limitations of this trial include an unblinded design, lack of blinded outcome assessment across the range of outcome measures, and differential dropout between groups, such that 13 individuals withdrew consent prior to treatment, 11 in the FESS group (21 percent) and two in the BOD group (four percent). The study population also included more than 25 percent of individuals with seasonal allergies and 60 percent of individuals with septal deviation, such that the effect of including concomitant conditions in the study population is unknown. In addition, more information is needed to determine which individuals and which sinuses benefit from the BOD as an adjunct to traditional FESS, and which individuals should get standard approaches.
As a follow up publication, Bizaki et al. (2015) reported on nasal airway resistance and sinus symptoms between FESS and BOD-treated groups. For this analysis, 62 individuals were included (32 from the FESS group and 30 from the BOD group). Individuals in the BOD group had significant improvements in nasal volume from pre- to post-operative measurements, but there were no significant differences between groups pre- or post-operatively in nasal volume.
An additional publication by Bizaki et al. (2014) reported on a randomized control trial (RCT) that compared BOD and FESS with a focus on mucociliary clearance. It was conducted at the same institution as the previously enrolled 36 individuals who were randomized to BOD or FESS; however, it is not specified that it was the same set of individuals. In addition, seven individuals dropped out and were not included in the analysis. SNOT-22 scores improved in both groups for pre- to post-operative analyses. However, change in total SNOT-22 scores did not differ significantly between groups. There were no significant change in mucociliary clearance before or after either treatment, and no significant between-group difference in mucociliary clearance.
In 2015, Chandra et al. reported the final results of up to two years post procedure for subjects in the REMODEL study, along with an additional 30 subjects treated with either FESS or in-office BOD, for a total of 61 FESS participants and 74 BOD participants. Follow-up data were available for 130, 66, and 25 subjects at 12, 18, and 24 months, respectively. Details about group-specific treatment received and loss to follow up are not reported for the additional 30 subjects not described by Cutler et al. (2013). The BOD group required 0.2 debridements per individual, compared with 1.0 per individual in the FESS group (p <0.0001). The mean change in SNOT-20 scores from baseline to 12-month follow-up was -1.59 (p <0.0001) and -1.60 (p <0.0001) for the BOD and FESS groups, respectively, which was considered clinically significant. These changes were maintained at 24 months. At 18 months, overall revision rates were 2.7 percent and 6.9 percent in the BOD and FESS groups, respectively. In addition to the longer-term results of the REMODEL trial, this article includes a meta-analysis of stand-alone BOD studies including the REMODEL BOD-treated individuals and data from six manufacturer-sponsored trials, three of which had previously been reported in peer-reviewed form. The meta-analysis included 846 individuals who were treated with BOD, including 121 who were not described in prior publications. In a random-effects model, overall mean and subscale values for the SNOT-20 scores improved compared with baseline at every follow-up time point. This evidence supports superiority for BOD as an alternative to FESS in individuals with CRS. The limitations of this study are consistent with earlier REMODEL reports.
In a prospective multicenter study, Gould et al (2014) reported the one-year outcomes from 81 individuals treated with an office-based BOD under local anesthesia for multisinus disease. Intra-operative procedure technical success and subject procedure tolerance were recorded. Efficacy was assessed using the participant-reported SNOT-20 and Rhinosinusitis Symptom Inventory (RSI). Complications and revision surgeries were also recorded. Analysis of data showed that among the study participants, mean procedure tolerance was 2.8 ± 2.2 (0 = no pain; 10 = severe pain). The participants also showed symptom improvement in mean overall SNOT-20 scores (p < 0.0001) observed at one and six months and sustained through one year. The RSI showed a treatment effect for all major rhinosinusitis symptoms, and improvement (p < 0.0001) in each was noted. Compared with the previous one-year period, individuals reported an average of 2.3 fewer acute sinus infections (p < 0.0001), 2.4 fewer antibiotic courses taken (p < 0.0001), and 3.0 fewer sinus-related physician visits (p < 0.0001) after BOD. No serious device- or procedure-related adverse events occurred. One individual (1.3 percent) underwent revision surgery. The study authors concluded that office-based multisinus BOD is safe, effective, and well tolerated. Although evidence may show some support for office-based BOD, this study, however had several limitations. For example, it lacked a comparison group to compare BOD to standard care in order to determine efficacy. Additionally, although all individuals were required to have documented CRS or recurrent acute rhinosinusitis and failure of maximal medical therapy, the specific medical therapy was not controlled, and adherence to medical treatment is unknown such that individual compliance reports could be inaccurate. The study population also included 65.8 percent of individuals with asthma and 59.8 percent of individuals with septal deviation, such that the effect of including concomitant conditions in the study population is unknown. Furthermore, the results of pre-enrollment CT scans were not provided to give a quantitative measure of disease severity. Concomitant turbinate reduction procedure was allowed and performed in 57 percent of the study participants, so it is unclear how this concomitant procedure affected the study outcomes. It is also unclear if SNOT-20 was validated for the different types of rhinosinusitis and was subject to the reliability of recall of individually-reported outcomes. Other limitations included small size, need for long-term follow-up time, and a lack of a control group, which prevented assessment of possible placebo effects.
A single-arm study reported by Tomazic et al. (2013), evaluated the feasibility of BOD in routine treatment of individuals with CRS refractory to medical therapy. Forty-five consecutive individuals were included in this study, in whom 112 sinuses were approached by BOD. Of the 112 sinuses, 68 (60 percent) were planned as a balloon-only procedure and 44 (40 percent) were planned as a hybrid procedure. Of the 68 sinuses in the balloon-only group, 44 sinuses failed, equating to a failure rate of 65 percent. Forty-four sinuses were planned for hybrid procedures. In 29 of these sinuses, BOD failed, giving a failure rate of 66 percent. The authors concluded that according to literature, BOD can be a useful adjunct technique to standard FESS. In their experience with this study, however, a failure rate of 65 percent for balloon-only and of 66 percent for hybrid procedures occurred, which was regarded as unacceptable. Therefore, the study initially scheduled for a cohort of 200 individuals, was abandoned.
A retrospective comparative study was published in 2012 by Koskinen et al. that included 53 participants with refractory CRS without previous sinonasal operations. The study was composed of 29 participants in the FESS group and 24 participants in the BOD group. The intent of this study was to compare the symptom outcomes after maxillary sinus surgery with either the FESS or the BOD technique. No previous or additional sinonasal operations were accepted. The individuals who met with the inclusion criteria replied to a questionnaire, which was mailed and contained questions on symptoms, exacerbations of chronic rhinosinusitis, medication use, work exposure, and the Lund-Mackay score. The Lund-Mackay score was assigned to each sinus based on the degree of mucosal inflammation or hypertrophy within the sinus. The mean symptom score was worse in the BOD group compared to the FESS group (4.37 vs. 3.22, p=0.04). Individuals in the BOD group reported a greater number of exacerbations compared to the FESS group. The majority of other outcome measures were similar between groups, and there were no measures on which the BOD group showed superior outcomes compared to the FESS group. The authors recommended that prospective randomized controlled trials with an increased number of participants are warranted.
Plaza et al. (2011) performed a randomized clinical trial comparing BOD/hybrid with FESS to FESS alone, for 32 individuals who had frontal sinus disease refractory to medical management. Primary outcome measurements at 12 months of follow-up included symptoms, the rhinosinusitis disability index, CT results of sinus patency, and the patency of the frontal recesses as assessed by endoscopy performed in an office setting. For both groups, there were improvements in symptoms and standardized rhinosinusitis scoring indices, but there were no differences between groups. There were also improvements in CT results of sinus patency in both groups but no differences between groups. There are several limitations to this study. It was inadequately powered and did not evaluate differences in outcomes between the two treatments, nor did it demonstrate that BOD is as safe and effective when compared to existing techniques.
An industry-sponsored prospective multicenter case series study named the Clinical Evaluation to Confirm Safety and Efficacy of Sinuplasty in the Paranasal Sinuses (CLEAR) compared the individual's baseline status to outcomes up to two years after surgery. The CLEAR study included consecutive individuals with CRS unresponsive to medical management who had either BOD alone for disease in the maxillary, frontal, or sphenoid sinuses, or had hybrid FESS if the disease was also located in the ethmoid sinus. Three articles were published from the CLEAR study (Bolger 2007, Kuhn 2008, Weiss 2008). The longest follow-up was 24 months, and outcomes from as many as 43 percent of individuals were lost to follow-up. Methodological flaws include potential biases created by lack of controls, no blinding, participant selection, a mixed population of primary and revisional surgeries, the proportion of individuals lost to follow-up, and manufacturer sponsorship of the study, all of which may impact the results of the reported data, so that efficacy cannot be determined.
Levine et al. (2008) discusses a multicenter retrospective uncontrolled review of 1036 individuals who underwent FESS that included the use of balloon catheters. Although in such combined procedures, it is difficult to assess which procedure contributed to clinical success or failure, these case series uniformly report symptom improvement, which appears to be durable in the subset of individuals followed for up to two years. Revision rates ranged between three and nine percent, but the follow-up time varied across studies. Acute adverse event rates appeared low. The authors report that there were differences between the groups with regard to blood loss, operation time, debridements, and endoscopies, with outcomes favoring BOD. However, no statistical data was provided to support this finding. Although none of the studies specify a protocol or procedure for identifying and recording adverse events, it might be presumed that the known adverse events of FESS, such as cerebral spinal fluid leakage or excessive bleeding, would be reasonably reported. In addition, the authors of this study cautioned that they did not provide a comparative outcome analysis of this retrospective review.
Balloon catheter dilation of sinus ostia, or BOD, has been studied as a minimally invasive alternative to FESS, or as an adjunct to endoscopic sinus surgery. The current literature has proven BOD to be safe and effective in the treatment of CRS. The variations observed in the literature for success rates, adverse event rates, and revision rates may be due to influences of disease severity. A complicating factor in the evaluation of this technology is depending on the individual and the judgment of the treating professional provider, FESS and BOD may be combined during one operation as a hybrid procedure. This creates challenges in deciphering what specific role each treatment is responsible for in the treatment outcomes. An opportunity exists for additional information on the durability of the procedure and which subset of individuals may require subsequent revision. Overall, the available scientific literature and professional societal guidelines endorse BOD. Balloon sinus ostia dilation, or BOD, can be considered as a course of treatment for individuals with persistent CRS.