Nasal Airflow Changes With Bioabsorbable Implant, Butterfly, and Spreader Grafts.

OBJECTIVES/HYPOTHESIS: Internal nasal valve compromise is a major cause of nasal obstruction, with a growing number of ways to treat this condition. In this study, we compared the effects of butterfly graft, spreader graft, and the bioabsorbable nasal implant on nasal airflow resistance. STUDY DESIGN: Cadaver study. METHODS: Computational fluid dynamics (CFD) simulations were completed from nine preoperative and postoperative cadaveric subjects. Each cadaveric head underwent placement of a bioabsorbable nasal implant (BNI) (Spirox Latera; Stryker ENT, Plymouth, MN), butterfly graft, or spreader graft. Pre- and postoperative computed tomography (CT) scans were used to generate three-dimensional models of the nasal airway used in steady-state CFD simulations of airflow and heat transfer during inspiration. RESULTS: Butterfly graft placement resulted in a mean improvement in nasal airway resistance of 24.9% (±7.3), whereas BNI placement resulted in a 6.7% (±1.2) improvement, and spreader graft placement also resulted in a consistent improvement of 2.6% (±13.5). Pressure within the main nasal cavity was consistently lower following butterfly graft placement versus a spreader graft or BNI. Butterfly and spreader graft placement also resulted in modest improvements in airflow allocation, whereas BNI demonstrated more variation (-1% to 12%). Heat flux was not significantly different; however, a small improvement in total heat flux was seen with all three interventions. CONCLUSIONS: The results of this study demonstrate reduction in nasal airway resistance in all three surgical interventions, with the butterfly graft demonstrating superiority to the other two techniques. However, these data only reflect a static environment and not dynamic changes in airflow seen during respiration. LEVEL OF EVIDENCE: NA Laryngoscope, 130:E817-E823, 2020.

Comparison of Airflow Between Spreader Grafts and Butterfly Grafts Using Computational Flow Dynamics in a Cadaveric Model.

IMPORTANCE: Nasal valve compromise is a major cause of nasal obstruction, and multiple methods have been developed to address it. OBJECTIVE: To compare nasal airflow resistance, airflow partitioning, and mucosal cooling (heat flux) before and after 2 surgical interventions, butterfly and spreader graft placement, used to treat nasal valve compromise. DESIGN, SETTING, AND PARTICIPANTS: In this cadaveric tissue study, 4 fresh cadaveric heads underwent both spreader graft and butterfly graft surgical procedures in alternating sequence in March 2016. Preoperative and postoperative computed tomographic scans were used to generate 3-dimensional (3-D) models of the nasal airway. These models were then used in steady state computational fluid dynamics simulations of airflow and heat transfer during inspiration. INTERVENTION: Butterfly and spreader graft techniques. MAIN OUTCOMES AND MEASURES: Nasal airflow resistance, airflow partitioning, and heat flux. RESULTS: Donors 1, 2, and 3 were white males; donor 4, a white female. Computational fluid dynamics simulations during inspiration in 3-D models generated from preoperative and postoperative computed tomographic scans of the 4 cadaveric heads indicated reductions from preoperative values in nasal airflow resistance associated with both butterfly grafts (range, 20%-51%) and spreader grafts (range, 2%-29%). Butterfly grafts were associated with a greater reduction in nasal airflow resistance in models of all 4 cadaveric heads. Changes from preoperative values for heat flux, a biophysical variable that correlates with the subjective sensation of nasal patency, were more variable, ranging from -11% to 4% following butterfly grafts and -9% to 10% following spreader grafts. The preoperative airflow allocation in the left and right nostrils improved consistently with the butterfly graft. With the spreader graft, there were improvements for donors 1 and 4, but the allocations were worse for donors 2 and 3. CONCLUSIONS AND RELEVANCE: The results of this study suggest that the more recently developed butterfly graft technique may be associated with a similar level of improved nasal airflow as that observed with the use of a spreader graft in nasal valve compromise. Both interventions were associated with comparable changes in heat flux. Because this study addressed only static internal nasal valve stenosis, even greater differences in air flow and heat flux between the 2 techniques may be anticipated in a dynamic model. Further investigation in patients is warranted. LEVEL OF EVIDENCE: NA.

Staging of Sinonasal and Ventral Skull Base Malignancies.

Tremendous pathologic diversity among sinonasal and ventral skull base malignancies complicates development of a uniform and prognostically relevant staging system. Because of the comparatively low incidence of these tumors, comprehensive evaluation and comparison of specific staging systems is difficult. The current American Joint Committee on Cancer TNM staging system for sinonasal malignancies is the most common and widely used system in current clinical practice. Alternative systems have been proposed for use with individual histopathologic subtypes. Many of these staging systems are of great utility and accurately predict patient survival. Further research and adjustment of these current staging systems remains an important area of research.

Transfacial and Craniofacial Approaches for Resection of Sinonasal and Ventral Skull Base Malignancies.

Malignancies of the paranasal sinuses and ventral skull base present unique challenges to physicians. A transfacial or craniofacial approach allows for wide, possibly en bloc, resection and is ideal for tumors that involve surrounding soft tissue, the palate, the orbit, anterolateral frontal sinus, and lateral dura. Transfacial approaches include a lateral rhinotomy often combined with a medial, subtotal, or total maxillectomy. Reconstruction is most commonly performed with a pericranial flap to separate the intranasal and intracranial compartments. These approaches have evolved and been refined but now are usually reserved for advanced tumors not amenable to endoscopic resection.