Inferior meatus augmentation procedure (IMAP) normalizes nasal airflow patterns in empty nose syndrome patients via computational fluid dynamics (CFD) modeling

Abstract

Background Empty nose syndrome ENS is a controversial upper airway disorder most commonly associated with tissue loss from the inferior turbinates The inferior meatus augmentation procedure IMAP has been shown to effectively reduce ENS symptoms in a durable manner but the precise mechanisms that may govern this symptomatic improvement remain unknown Methods Five patients with ENS who underwent bilateral IMAP via submucosal costal cartilage implant were assessed Pre-implant and months post-implant computed tomography CT imaging for each ENS patient was analyzed in a blinded fashion using computational fluid dynamics CFD modeling to investigate intrapatient changes in airflow parameters Results Following surgery ENS patients have significantly improved symptoms as indexed by Empty Nose Syndrome -Item Questionnaire ENS Q scoring pre-implant ± mean ± standard deviation confidence interval CI to post-implant ± CI to Cohen's d = p = Using CFD a significant shi in nasal airflow patterns was observed where airflow deviates away from the middle meatus upon hitting the implant pre-implant ± CI to post-implant ± CI to d = p < toward the inferior meatus pre-implant ± CI to post-implant ± CI to d = p < No significant changes were found in nasal resistance pre-implant ± CI to Pa*s/mL post-implant ± CI toPa*s/mL In addition the improvement of ENS Q scoring significantly correlated with percent reduction in aberrant airflow through the middle meatus R = p = Conclusion This study supports our prior working hypothesis that disordered vectors of nasal airflow congregate in the middle meatus contribute to ENS symptoms not nasal resistance Moreover these data illuminate a paradoxical but consistent restoration of nasal airflow to the inferior meatus following the replacement of turbinate tissue volume in the inferior meatus via IMAP surgery potentially due to the Coandȃ effect © 2020 ARS-AAOA, LLC.

Inferior Meatus Augmentation Procedure (IMAP) for Treatment of Empty Nose Syndrome

“…2 Blinded computational fluid dynamics assessment of patients with ENS following IMAP demonstrated that this procedure restores normal airflow patterns toward the inferior meatus while concomitantly reducing aberrant airflow through the middle meatus. 3 Importantly, our group has also shown that ENS patients often experience improvements in aspects of their psychological well-being and overall quality of life following IMAP, as determined by significant reductions in the Generalized Anxiety Disorder 7-item scale (GAD-7), and Patient Health Questionnaire-9 (PHQ-9), and Sinonasal Outcome Test (SNOT-22) scores. 2 All score improvements remained statistically significant at 1 year postoperatively, suggesting that the benefits of nasal airway augmentation surgery can be sustained long term.…”

“…Patient‐reported nasal breathing outcomes as measured by the ENS6Q showed significant and sustained improvements 1 year following IMAP with cadaveric rib 2 . Blinded computational fluid dynamics assessment of patients with ENS following IMAP demonstrated that this procedure restores normal airflow patterns toward the inferior meatus while concomitantly reducing aberrant airflow through the middle meatus 3 . Importantly, our group has also shown that ENS patients often experience improvements in aspects of their psychological well‐being and overall quality of life following IMAP, as determined by significant reductions in the Generalized Anxiety Disorder 7‐item scale (GAD‐7), and Patient Health Questionnaire‐9 (PHQ‐9), and Sinonasal Outcome Test (SNOT‐22) scores 2 .…”

“…The IMAP technique has demonstrated favorable long-term outcomes for this disease entity that has historically been difficult to manage and/or been deemed untreatable, with significant reductions in patient-reported symptoms as measured by the Empty Nose Syndrome 6-Item Questionnaire (ENS6Q) 2 and normalization of nasal airflow patterns as demonstrated by computational fluid dynamic studies. 3 Here we describe the operative and perioperative details for the IMAP.…”

“…In the majority of patients suffering from ENS symptoms, there is typically insufficient IT bone remaining in this region to accommodate placement of a bulky tissue graft, therefore, the inferior meatus and inferolateral nasal wall become the next‐best regional site to recreate the rounded, tubular contour, and position of the native turbinate organ. The IMAP technique has demonstrated favorable long‐term outcomes for this disease entity that has historically been difficult to manage and/or been deemed untreatable, with significant reductions in patient‐reported symptoms as measured by the Empty Nose Syndrome 6‐Item Questionnaire (ENS6Q) 2 and normalization of nasal airflow patterns as demonstrated by computational fluid dynamic studies 3 . Here we describe the operative and perioperative details for the IMAP.…”

Long‐Term Outcomes of Inferior Meatus Augmentation Procedure to Treat Empty Nose Syndrome

“…Nevertheless, we believe patients undergoing IMAP show significant improvements because of the ability of IMAP to restore inferior turbinate volume and thereby normalize aberrant nasal aerodynamics in ENS patients, an effect which has been demonstrated by our collaborative group using computational fluid dynamics analysis in these postoperative patients. 19 Our group has previously reported that IMAP utilizing acellular dermal matrix or SIS graft provides significant improvements in ENS, sinonasal, anxiety, and depression symptoms. 9,10 However, we also reported the limitations of this prior study, which included a small sample size, concurrent sinus surgeries, limited followup, and the transition to a different implant material due to resorption.…”