ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

AIRFLOW VENTILATION THROUGH HUMAN MAXILLARY
SINUSES WITH SINGLE/TWIN ACCESSORY OSTIA: A CFD
SMULATION STUDY
Jian Hua Zhu 1 , Heow Pueh Lee 2 , Kian Meng Lim 3 , Shu Jin Lee 4 , Lynette Teo Li
San 5 and De Yun Wang 6
1. ABSTRACT
The effects of accessory ostium (AO) on ventilation through human maxillary sinus are
to be determined. In this study, realistic 3-Dimensional nasal models of two subjects
were reconstructed: one possessed two AOs on the left side of the nasal cavity (sinus I)
and one AO on the right side (sinus II); and the other subject without AO was recruited
for comparison (sinus III). Transient simulations corresponding to both calm respiration
(15 L/min) and nasal blow (48 L/min) were carried out with these two models using
low-Reynolds-number turbulent model. The results show that, at low flow rate, the
airflow through sinuses I and II were comparable, while the airflow through sinus III
was markedly lower. The flow direction through sinus I changed between inspiration
and expiration, while remained the same almost through the whole respiration cycle in
sinus II. Under high flow conditions mimicking nose blowing, in sinus II, the maximum
sinus flow rate increased compared to low flow rate. While it remained almost constant
in sinus I. In conclusion, the existences of AOs significantly increased the gas exchange
between maxillary sinus and nasal cavity. Whether these airflow changes impact
maxillary sinus physiology or pathophysiology is unknown.
2. INTRODUCTION
The natural ostium (NO) of maxillary sinus, connecting the sinus and nasal cavity, is the
only passage for gas exchange between these two lumens when the accessory ostium
(AO) is absent. The prevalence of AO was estimated to be between 4 and 50 percent 1 .
In the past, the existence of AO was found to be associated with mucus circulation
between AO and NO 2 . The circulation of mucus was considered as a cause of persistent
sinusitis and chronic maxillary sinus disease 3 . The air ventilation through maxillary
1 Phd Candidate, Department of Mechanical Engineering, National University of Singapore, Singapore
2 Associate Professor, Department of Mechanical Engineering, National University of Singapore,
Singapore
3 Associate Professor, Department of Mechanical Engineering, National University of Singapore,
Singapore
4 Consultant and Assistant Professor, Division of Plastic and Reconstructive Surgery, National University
Hospital, Singapore
5 Consultant and Assistant Professor, Department of Diagnostic Radiology, National University of
Singapore, Singapore
6 Associate Professor, Department of Otolaryngology, National University of Singapore, Singapore