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Li Y, Yu C, Li P, Qian X, Song P, Gao X. A Preliminary Report on the Correlation Between Nasal Function and the Different Phases of the Nasal Cycle. EAR, NOSE & THROAT JOURNAL 2024; 103:339-343. [PMID: 34463151 DOI: 10.1177/01455613211041788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To explore whether the different phases of the nasal cycle have a significant effect on nasal temperature, the nasal mucosal clearance rate, and levels of nasal nitric oxide (nNO) and to investigate the correlation between these nasal conditions. METHODS The study participants were divided into 2 groups: the control group and the rhinitis group. The participants' nasal temperature, cilia clearance rate, and nNO levels were measured during different phases of the nasal cycle (the congestion phase and decongestion phase) in the control group and before and after undergoing inferior turbinate ablation in the rhinitis group. RESULTS The temperature of the nasal cavity in the control group was significantly higher in the congestion phase than in the decongestion phase (P = .0025), while in the rhinitis group, the temperature of the nasal cavity decreased significantly after inferior turbinate ablation (P = .001). In the control group, the nasal mucosa clearance time was significantly shorter in the congestion phase than in the decongestion phase (P = .001), and in the rhinitis group, the clearance time of the nasal mucosa was significantly shortened after the operation (P = .0025). In the control group, the levels of nNO were significantly higher in the congestion phase than in the decongestion phase (P = .025), while in the rhinitis group, nNO levels decreased significantly after the operation (P = .005). CONCLUSION The function of the nasal cavity changes in different phases of the nasal cycle. Therefore, when evaluating the impact of various factors on nasal function, factors associated with the nasal cycle should also be considered. Inferior turbinate plasma ablation can improve the ciliary function of the nasal mucosa, reduce the temperature of the nasal cavity, and reduce nNO levels.
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Affiliation(s)
- Yihan Li
- Department of Otolaryngology, HUADONG Sanatorium, Wuxi, Jiangsu Province, China
| | - Chenjie Yu
- Department of Otorhinolaryngology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Jiangsu Provincial Key Medical Discipline (Laboratory), Nanjing, China
| | - Peizhong Li
- Department of Otolaryngology, Head and Neck Surgery, The No 1 Hospital of Huaian, Nanjing Medical University, Nanjing, China
| | - Xiaoyun Qian
- Department of Otorhinolaryngology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Jiangsu Provincial Key Medical Discipline (Laboratory), Nanjing, China
| | - Panpan Song
- Department of Otorhinolaryngology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Jiangsu Provincial Key Medical Discipline (Laboratory), Nanjing, China
| | - Xia Gao
- Department of Otorhinolaryngology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Jiangsu Provincial Key Medical Discipline (Laboratory), Nanjing, China
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Servos Li MM, Hamersley ERS, Baldassari C. Nasal Disorders. Pediatr Rev 2024; 45:188-200. [PMID: 38556515 DOI: 10.1542/pir.2023-006012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
Nasal obstruction, rhinorrhea, and epistaxis are common presenting concerns in primary care clinics. Nasal disorders affect the quality of life for many children and families. Rarely, these complaints may represent a life-threatening condition among infant obligate nasal breathers or cases of unusual pathology. The most common causes of rhinorrhea and nasal obstruction vary by age and include physiologic, infectious, allergic, foreign body, irritant, and traumatic causes. Less commonly, children may have congenital malformations, sinonasal masses, or autoimmune disease. The most common causes of epistaxis are inflammatory, environmental, and traumatic causes and medication misuse, but rarely, children may have predisposing anatomic, hematologic, or vascular abnormalities or even sinonasal tumors. In this article, we provide a thorough review of the common nasal disorders treated every day in primary care clinics and mention briefly some of the rare but serious cases that may be overlooked without considering a full differential diagnosis.
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Affiliation(s)
- Mariah M Servos Li
- Department of Otolaryngology-Head and Neck Surgery, Eastern Virginia Medical School, Norfolk, VA
| | - Erin R S Hamersley
- Department of Otolaryngology-Head and Neck Surgery, Eastern Virginia Medical School, Norfolk, VA
- Department of Otolaryngology-Head and Neck Surgery, Naval Medical Center Portsmouth, Portsmouth, VA
| | - Cristina Baldassari
- Department of Otolaryngology-Head and Neck Surgery, Eastern Virginia Medical School, Norfolk, VA
- Department of Pediatric Sleep Medicine, Children's Hospital of the King's Daughters, Norfolk, VA
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Chong AXJ, Alvarado R, Rimmer J, Campbell RG, Kalish L, Png LH, Harvey RJ. Comparison of Allergen Immunotherapy Alone and in Conjunction With Turbinate Surgery for Nasal Obstruction in Perennial Allergic Rhinitis Patients. Ann Otol Rhinol Laryngol 2024:34894241234593. [PMID: 38414187 DOI: 10.1177/00034894241234593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
BACKGROUND Nasal obstruction, triggered by allergic rhinitis, often does not resolve with allergen-specific immunotherapy (AIT) alone, thus inferior turbinate reduction surgery (ITR) may be required. This study aims to investigate the impact of combined treatment on nasal obstruction, as evidence is currently limited. METHODOLOGY/PRINCIPAL A retrospective cohort study of perennial allergic rhinitis patients experiencing nasal obstruction and undergoing ≥12 months AIT was conducted. Two groups were derived, those undergoing AIT-with or without an ITR. Patient reported nasal obstruction (evaluated with questionnaires) and nasal airway function (Nasal Peak Inspiratory Flow [NPIF] and Nasal Airflow Resistance [NAR]) were monitored. The change from baseline to 12 months post-treatment in each group were compared. RESULTS A total of 118 patients (33.71 ± 14.43 years, 41.5% female) were recruited, 72% had AIT and 28% AIT&ITR. At baseline, the AIT&ITR group had a higher level of nasal obstruction (>moderate%; 63.6% vs 52.9%, P = .048). Post treatment, AIT&ITR group reported greater reduction in nasal obstruction (>1 category change: 75.8% vs 48.2%, P = .002). Similarly, the AIT&ITR group had greater improvement in nasal function by NPIF (-13.9 ± 110.3 L/minute vs -3.4 ± 78.1 L/minute, P = .049) and NAR (-0.120 ± 0.342 Pa/cm³/second vs -0.093 ± 0.224 Pa/cm³/second, P = .050). CONCLUSIONS Allergic rhinitis patients, with moderate to severe nasal obstruction, who undergo combined AIT&ITR have greater relief of nasal obstruction and improved airflow analysis compared to AIT alone.
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Affiliation(s)
- Amaris Xin Jie Chong
- Rhinology and Skull Base Research Group, St Vincent's Centre for Applied Medical Research, Sydney, NSW, Australia
- Faculty of Medicine, University of New South Wales Sydney, Sydney, NSW, Australia
| | - Raquel Alvarado
- Rhinology and Skull Base Research Group, St Vincent's Centre for Applied Medical Research, Sydney, NSW, Australia
| | - Janet Rimmer
- Rhinology and Skull Base Research Group, St Vincent's Centre for Applied Medical Research, Sydney, NSW, Australia
- Woolcock Institute, University of Sydney, Sydney, Australia
- Faculty of Medicine, Notre Dame University, Sydney, Australia
| | - Raewyn G Campbell
- Rhinology and Skull Base Research Group, St Vincent's Centre for Applied Medical Research, Sydney, NSW, Australia
- Department of Otolaryngology, Head and Neck Surgery, Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - Larry Kalish
- Rhinology and Skull Base Research Group, St Vincent's Centre for Applied Medical Research, Sydney, NSW, Australia
- Department of Otolaryngology, Head and Neck Surgery, Concord Repatriation General Hospital, Sydney, NSW, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Lu Hui Png
- Rhinology and Skull Base Research Group, St Vincent's Centre for Applied Medical Research, Sydney, NSW, Australia
- Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
- Singapore General Hospital, Singapore, Singapore
| | - Richard J Harvey
- Rhinology and Skull Base Research Group, St Vincent's Centre for Applied Medical Research, Sydney, NSW, Australia
- Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
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Seifelnasr A, Si X, Xi J. Assessing Nasal Epithelial Dynamics: Impact of the Natural Nasal Cycle on Intranasal Spray Deposition. Pharmaceuticals (Basel) 2024; 17:73. [PMID: 38256906 PMCID: PMC10819912 DOI: 10.3390/ph17010073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 12/31/2023] [Accepted: 01/05/2024] [Indexed: 01/24/2024] Open
Abstract
This study investigated the intricate dynamics of intranasal spray deposition within nasal models, considering variations in head orientation and stages of the nasal cycle. Employing controlled delivery conditions, we compared the deposition patterns of saline nasal sprays in models representing congestion (N1), normal (N0), and decongestion (P1, P2) during one nasal cycle. The results highlighted the impact of the nasal cycle on spray distribution, with congestion leading to confined deposition and decongestion allowing for broader dispersion of spray droplets and increased sedimentation towards the posterior turbinate. In particular, the progressive nasal dilation from N1 to P2 decreased the spray deposition in the middle turbinate. The head angle, in conjunction with the nasal cycle, significantly influenced the nasal spray deposition distribution, affecting targeted drug delivery within the nasal cavity. Despite controlled parameters, a notable variance in deposition was observed, emphasizing the complex interplay of gravity, flow shear, nasal cycle, and nasal morphology. The magnitude of variance increased as the head tilt angle increased backward from upright to 22.5° to 45° due to increasing gravity and liquid film destabilization, especially under decongestion conditions (P1, P2). This study's findings underscore the importance of considering both natural physiological variations and head orientation in optimizing intranasal drug delivery.
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Affiliation(s)
- Amr Seifelnasr
- Department of Biomedical Engineering, University of Massachusetts, Lowell, MA 01854, USA;
| | - Xiuhua Si
- Department of Mechanical Engineering, California Baptist University, Riverside, CA 92504, USA;
| | - Jinxiang Xi
- Department of Biomedical Engineering, University of Massachusetts, Lowell, MA 01854, USA;
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Kumar A, Joshi D. Effect of ambient temperature and respiration rate on nasal dominance: preliminary findings from a nostril-specific wearable. J Breath Res 2023; 17:046011. [PMID: 37611568 DOI: 10.1088/1752-7163/acf339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 08/23/2023] [Indexed: 08/25/2023]
Abstract
The nasal dominance (ND) determination is crucial for nasal synchronized ventilator, optimum nasal drug delivery, identifying brain hemispheric dominance, nasal airway obstruction surgery, mindfulness breathing, and for possible markers of a conscious state. Given these wider applications of ND, it is interesting to understand the patterns of ND with varying temperature and respiration rates. In this paper, we propose a method which measures peak-to-peak temperature oscillations (difference between end-expiratory and end-inspiratory temperature) for the left and right nostrils during nasal breathing. These nostril-specific temperature oscillations are further used to calculate the nasal dominance index (NDI), nasal laterality ratio (NLR), inter-nostril correlation, and mean of peak-to-peak temperature oscillation for inspiratory and expiratory phase at (1) different ambient temperatures of 18 °C, 28 °C, and 38 °C and (2) at three different respiration rate of 6 bpm, 12 bpm, and 18 bpm. The peak-to-peak temperature (Tpp) oscillation range (averaged across participants;n= 8) for the left and right nostril were 3.80 ± 0.57 °C and 2.34 ± 0.61 °C, 2.03 ± 0.20 °C and 1.40 ± 0.26 °C, and 0.20 ± 0.02 °C and 0.29 ± 0.03 °C at the ambient temperature of 18 °C, 28 °C, and 38 °C respectively (averaged across participants and respiration rates). The NDI and NLR averaged across participants and three different respiration rates were 35.67 ± 5.53 and 2.03 ± 1.12; 8.36 ± 10.61 and 2.49 ± 3.69; and -25.04 ± 14.50 and 0.82 ± 0.54 at the ambient temperature of 18 °C, 28 °C, and 38 °C respectively. The Shapiro-Wilk test, and non-parametric Friedman test showed a significant effect of ambient temperature conditions on both NDI and NLR. No significant effect of respiration rate condition was observed on both NDI and NLR. The findings of the proposed study indicate the importance of ambient temperature while determining ND during the diagnosis of breathing disorders such as septum deviation, nasal polyps, nosebleeds, rhinitis, and nasal fractions, and in the intensive care unit for nasal synchronized ventilator.
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Affiliation(s)
- Amit Kumar
- Centre for Biomedical Engineering, Indian Institute of Technology Delhi, New Delhi, India
| | - Deepak Joshi
- Department of Biomedical Engineering, All India Institute of Medical Sciences, New Delhi, India
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Reeve J, Mooney S, Jepsen N, White D. The Utility and Acceptability of a New Noninvasive Ventilatory Assist Device, Rest-Activity Cycler-Positive Airways Pressure, During Exercise in a Population of Healthy Adults: Cohort Study. JMIR Rehabil Assist Technol 2022; 9:e35494. [PMID: 35916705 PMCID: PMC9379794 DOI: 10.2196/35494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 05/30/2022] [Accepted: 06/10/2022] [Indexed: 11/17/2022] Open
Abstract
Background Noninvasive ventilation has been demonstrated to benefit people who have moderate to severe chronic obstructive pulmonary disease during acute exacerbations. Studies have begun to investigate the effectiveness of noninvasive ventilation during pulmonary rehabilitation to improve outcomes for people with chronic obstructive pulmonary disease; however, the lack of portability and humidification of these devices means their use is limited, especially when performing activities of daily living. A new prototype device, RACer-PAP (rest-activity cycler-positive airways pressure), delivers battery-operated positive airway pressure via a nasal interface while regulating nasal airway apportionment bias, removing the need for supplementary humidification. This device may offer people with chronic obstructive pulmonary disease an improved ability to participate in pulmonary rehabilitation and activities of daily living. Objective To assess the feasibility of exercising with the RACer-PAP in situ and the acceptability of the device during exercise in normal, healthy individuals. Methods A total of 15 healthy adults were invited to attend 2 exercise sessions, each 1 week apart. Sessions lasted approximately 1 hour and included 2 baseline 6-minute walk distance assessments, once with and once without the RACer-PAP in situ. Vital signs and spirometry results were monitored throughout, and spirometry was performed pre- and posttesting with RACer-PAP. Subjective questionnaires ascertained participant feedback on exercising with the device in situ. Results Of the 15 initial participants, 14 (93%) completed both sessions. There were no adverse events associated with exercising with the device in situ. There were no differences in vital signs or 6-minute walk distance whether exercising with or without the device in situ. There were small increases in maximum dyspnea score (on the Borg scale) when exercising with the device in situ (median score 2.0, IQR 0.5-3.0, vs 3.0, IQR 2.0-3.25). There were small increases in forced vital capacity following exercise with the RACer-PAP. None of the participants reported symptoms associated with airway drying. Participant feedback provided recommendations for modifications for the next iteration of the device prior to piloting the device with people with chronic obstructive pulmonary disease. Conclusions This study has shown RACer-PAP to be safe and feasible to use during exercise and has provided feedback for modifications to the device to improve its use during exercise. We now propose to consider the application of the device in a small pilot feasibility study to assess the safety, feasibility, and utility of the device in a population of people with moderate to severe chronic obstructive pulmonary disease. Trial Registration Australian New Zealand Clinical Trials Registry ACTRN12619000478112; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=375477
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Affiliation(s)
- Julie Reeve
- School of Clinical Sciences, Auckland University of Technology, Auckland, New Zealand
| | - Sarah Mooney
- School of Clinical Sciences, Auckland University of Technology, Auckland, New Zealand
| | - Nicola Jepsen
- School of Clinical Sciences, Auckland University of Technology, Auckland, New Zealand
| | - David White
- Department of Mechanical Engineering, Auckland University of Technology, Auckland, New Zealand
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Niazi IK, Navid MS, Bartley J, Shepherd D, Pedersen M, Burns G, Taylor D, White DE. EEG signatures change during unilateral Yogi nasal breathing. Sci Rep 2022; 12:520. [PMID: 35017606 PMCID: PMC8752782 DOI: 10.1038/s41598-021-04461-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 12/23/2021] [Indexed: 01/06/2023] Open
Abstract
Airflow through the left-and-right nostrils is said to be entrained by an endogenous nasal cycle paced by both poles of the hypothalamus. Yogic practices suggest, and scientific evidence demonstrates, that right-nostril breathing is involved with relatively higher sympathetic activity (arousal states), while left-nostril breathing is associated with a relatively more parasympathetic activity (stress alleviating state). The objective of this study was to further explore this laterality by controlling nasal airflow and observing patterns of cortical activity through encephalographic (EEG) recordings. Thirty subjects participated in this crossover study. The experimental session consisted of a resting phase (baseline), then a period of unilateral nostril breathing (UNB) using the dominant nasal airway, followed by UNB using the non-dominant nasal airway. A 64-channel EEG was recorded throughout the whole session. The effects of nostril-dominance, and nostril-lateralization were assessed using the power spectral density of the neural activity. The differences in power-spectra and source localization were calculated between EEG recorded during UNB and baseline for delta, theta, alpha, beta and gamma bands. Cluster-based permutation tests showed that compared to baseline, EEG spectral power was significantly (1) decreased in all frequency bands for non-dominant nostril UNB, (2) decreased in alpha, beta and gamma bands for dominant nostril UNB, (3) decreased in all bands for left nostril UNB, and (4) decreased in all bands except delta for right nostril UNB. The beta band showed the most widely distributed changes across the scalp. our source localisation results show that breathing with the dominant nostril breathing increases EEG power in the left inferior frontal (alpha band) and left parietal lobule (beta band), whereas non-dominant nostril breathing is related to more diffuse and bilateral effects in posterior areas of the brain.These preliminary findings may stimulate further research in the area, with potential applications to tailored treatment of brain disorders associated with disruption of sympathetic and parasympathetic activity.
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Affiliation(s)
- Imran Khan Niazi
- BioDesign Lab, School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand.
- New Zealand College of Chiropractic, Auckland, New Zealand.
- Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
| | | | - Jim Bartley
- BioDesign Lab, School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand
| | - Daniel Shepherd
- School of Psychology & Neuroscience, Auckland University of Technology, Auckland, New Zealand
| | - Mangor Pedersen
- School of Psychology & Neuroscience, Auckland University of Technology, Auckland, New Zealand
| | - Georgina Burns
- Rehabilitation Innovation Centre, Health & Rehabilitation Research Institute, AUT University, Auckland, New Zealand
| | - Denise Taylor
- Rehabilitation Innovation Centre, Health & Rehabilitation Research Institute, AUT University, Auckland, New Zealand
| | - David E White
- BioDesign Lab, School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand
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Using the Intranasal Route to Administer Drugs to Treat Neurological and Psychiatric Illnesses: Rationale, Successes, and Future Needs. CNS Drugs 2022; 36:739-770. [PMID: 35759210 PMCID: PMC9243954 DOI: 10.1007/s40263-022-00930-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/19/2022] [Indexed: 11/17/2022]
Abstract
While the intranasal administration of drugs to the brain has been gaining both research attention and regulatory success over the past several years, key fundamental and translational challenges remain to fully leveraging the promise of this drug delivery pathway for improving the treatment of various neurological and psychiatric illnesses. In response, this review highlights the current state of understanding of the nose-to-brain drug delivery pathway and how both biological and clinical barriers to drug transport using the pathway can been addressed, as illustrated by demonstrations of how currently approved intranasal sprays leverage these pathways to enable the design of successful therapies. Moving forward, aiming to better exploit the understanding of this fundamental pathway, we also outline the development of nanoparticle systems that show improvement in delivering approved drugs to the brain and how engineered nanoparticle formulations could aid in breakthroughs in terms of delivering emerging drugs and therapeutics while avoiding systemic adverse effects.
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Huijghebaert S, Hoste L, Vanham G. Essentials in saline pharmacology for nasal or respiratory hygiene in times of COVID-19. Eur J Clin Pharmacol 2021; 77:1275-1293. [PMID: 33772626 PMCID: PMC7998085 DOI: 10.1007/s00228-021-03102-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 01/28/2021] [Indexed: 12/11/2022]
Abstract
PURPOSE Nasal irrigation or nebulizing aerosol of isotonic or hypertonic saline is a traditional method for respiratory or nasal care. A recent small study in outpatients with COVID-19 without acute respiratory distress syndrome suggests substantial symptom resolution. We therefore analyzed pharmacological/pharmacodynamic effects of isotonic or hypertonic saline, relevant to SARS-CoV-2 infection and respiratory care. METHODS Mixed search method. RESULTS Due to its wetting properties, saline achieves an improved spreading of alveolar lining fluid and has been shown to reduce bio-aerosols and viral load. Saline provides moisture to respiratory epithelia and gels mucus, promotes ciliary beating, and improves mucociliary clearance. Coronaviruses and SARS-CoV-2 damage ciliated epithelium in the nose and airways. Saline inhibits SARS-CoV-2 replication in Vero cells; possible interactions involve the viral ACE2-entry mechanism (chloride-dependent ACE2 configuration), furin and 3CLpro (inhibition by NaCl), and the sodium channel ENaC. Saline shifts myeloperoxidase activity in epithelial or phagocytic cells to produce hypochlorous acid. Clinically, nasal or respiratory airway care with saline reduces symptoms of seasonal coronaviruses and other common cold viruses. Its use as aerosol reduces hospitalization rates for bronchiolitis in children. Preliminary data suggest symptom reduction in symptomatic COVID-19 patients if saline is initiated within 48 h of symptom onset. CONCLUSIONS Saline interacts at various levels relevant to nasal or respiratory hygiene (nasal irrigation, gargling or aerosol). If used from the onset of common cold symptoms, it may represent a useful add-on to first-line interventions for COVID-19. Formal evaluation in mild COVID-19 is desirable as to establish efficacy and optimal treatment regimens.
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Affiliation(s)
| | - Levi Hoste
- Pediatric Pulmonology, Infectious Diseases and Immunology, Ghent University Hospital, Ghent, Belgium
- Primary Immunodeficiency Research Lab, Center for Primary Immunodeficiency Ghent, Jeffrey Modell Diagnosis and Research Center, Ghent University Hospital, Ghent, Belgium
| | - Guido Vanham
- Department of Biomedical Sciences, Institute of Tropical Medicine and University of Antwerp, Antwerp, Belgium
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Sinha S, Mittal S, Bhat S, Baro G. Effect of Nasal Dominance on Pulmonary Function Test and Heart Rate: A Pilot Study. Int J Yoga 2021; 14:141-145. [PMID: 34188386 PMCID: PMC8191224 DOI: 10.4103/ijoy.ijoy_115_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 02/04/2021] [Accepted: 03/02/2021] [Indexed: 11/22/2022] Open
Abstract
Background: The nasal cycle is one of the many cyclic events in a human being. Nasal airflow is greater in one nostril at any given point in time and this alternates between right and left nostrils over time. Its periodicity ranges from 25 min to 8 h. This alteration has been known to be controlled by the autonomic nervous system. The current study was designed to assess the effect of nasal dominance during rest on pulmonary function parameters and heart rate. Materials and Methods: A cross-sectional study was done on 35 apparently healthy individuals of the age group of 18–30 years. Based on a cold mirror test, the participants were categorized into two groups of right nasal dominance (RND) and left nasal dominance (LND). The parameters recorded were forced expiratory volume in the first sec (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow rate, forced expiratory flow between 25%-75%, SpO2, and pulse rate. Data were expressed as mean ± standard deviation and were analyzed using SPSS version 20. Results: All pulmonary function parameters exhibited higher values in RND participants compared to LND participants and the difference was found to be statistically significant (P < 0.05). Conclusion: Nasal dominance has a measurable effect on pulmonary functions and heart rate hence emphasizing the role of autonomic control of airways. This influence can be used as adjuvant therapy for certain disorders.
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Affiliation(s)
- Smriti Sinha
- Department of Physiology, Andhra Medical College, Visakhapatnam, Andhra Pradesh, India
| | - Swati Mittal
- Department of Physiology, All India Institute of Medical Sciences, Deoghar, Jharkhand, India
| | - Shilpi Bhat
- Department of Physiology, School of Medical Sciences and Research, Greater Noida, Uttar Pradesh, India
| | - Geeta Baro
- Department of Physiology, School of Medical Sciences and Research, Greater Noida, Uttar Pradesh, India
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Can computational fluid dynamic models help us in the treatment of chronic rhinosinusitis. Curr Opin Otolaryngol Head Neck Surg 2020; 29:21-26. [PMID: 33315616 DOI: 10.1097/moo.0000000000000682] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW The aim of this study was to review the recent literature (January 2017-July 2020) on computational fluid dynamics (CFD) studies relating to chronic rhinosinusitis (CRS), including airflow within the pre and postoperative sinonasal cavity, virtual surgery, topical drug and saline delivery (sprays, nebulizers and rinses) and olfaction. RECENT FINDINGS Novel CFD-specific parameters (heat flux and wall shear stress) are highly correlated with patient perception of nasal patency. Increased ostial size markedly improves sinus ventilation and drug delivery. New virtual surgery tools allow surgeons to optimize interventions. Sinus deposition of nasal sprays is more effective with smaller, low-inertia particles, outside of the range produced by many commercially available products. Saline irrigation effectiveness is improved using greater volume, with liquid entering sinuses via 'flooding' of ostia rather than direct jet entry. SUMMARY CFD has provided new insights into sinonasal airflow, air-conditioning function, the nasal cycle, novel measures of nasal patency and the impact of polyps and sinus surgery on olfaction. The deposition efficiency of topical medications on sinus mucosa can be markedly improved through parametric CFD experiments by optimising nasal spray particle size and velocity, nozzle angle and insertion location, while saline irrigation effectiveness can be optimized by modelling squeeze bottle volume and head position. More sophisticated CFD models (inhalation and exhalation, spray particle and saline irrigation) will increasingly provide translational benefits in the clinical management of CRS.
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12
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Salati H, Bartley J, Yazdi SG, Jermy M, White DE. Neti pot irrigation volume filling simulation using anatomically accurate in-vivo nasal airway geometry. Respir Physiol Neurobiol 2020; 284:103580. [PMID: 33161119 DOI: 10.1016/j.resp.2020.103580] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Revised: 11/02/2020] [Accepted: 11/03/2020] [Indexed: 11/25/2022]
Abstract
Nasal saline irrigation is frequently utilised in rhinosinusitis management, and after nasal and sinus surgery. Nasal saline irrigation improves mucociliary transport and assists inflammatory mediator and post-surgical debris removal. The aim of this study was to assess the influence different head positions, irrigation inflow nostril, and the nasal cycle have on Neti pot nasal saline volume filling within the nasal passages and maxillary sinuses. Computational fluid dynamics modelling using anatomically correct nasal geometry found only minor difference in nasal cavity volume filling with inflow from either side of the nose however both head position and inflow direction were both found to have a major influence on maxillary sinus volume filling. Computational modelling flow velocity results at the nasopharynx were validated using particle image velocimetry. It was also found that directing irrigation inflow into the patent side of the nose while in the head-back position achieved the highest volume filling of both maxillary sinuses.
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Affiliation(s)
- Hana Salati
- BioDesign Lab, School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand.
| | - Jim Bartley
- Department of Surgery, University of Auckland, Auckland, New Zealand.
| | - Sina G Yazdi
- Department of Mechanical Engineering, University of Canterbury, Christchurch, New Zealand.
| | - Mark Jermy
- Department of Mechanical Engineering, University of Canterbury, Christchurch, New Zealand.
| | - David E White
- BioDesign Lab, School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand.
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Yarragudi SB, Kumar H, Jain R, Tawhai M, Rizwan S. Olfactory Targeting of Microparticles Through Inhalation and Bi-directional Airflow: Effect of Particle Size and Nasal Anatomy. J Aerosol Med Pulm Drug Deliv 2020; 33:258-270. [PMID: 32423267 DOI: 10.1089/jamp.2019.1549] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Background: Targeting drugs to the olfactory region in the nasal cavity can bypass the restrictive blood-brain barrier and enhance their direct delivery to the brain. However, complex nasal geometry and its demographical variations can pose challenges for targeted drug deposition in the olfactory region. Deposition of particles in the nasal cavity is influenced by particle size, airflow rate, and nasal geometry. Therefore, this study investigated the effect of these parameters on regional microparticle deposition with the view to provide insights into the nose-to-brain delivery of drugs. Methods: In this study, three anatomically accurate human nasal cavities were reconstructed in silico and deposition of microparticles under nebulization and bi-directional airflow conditions was simulated. Microparticle deposition data were analyzed to gain insight into the effect of particle size and nasal geometry. Results: Maximum olfactory deposition was observed with particles in the size range of 8 to 12 μm under nebulization and 14 to 18 μm under bi-directional airflow condition. Geometric differences between subjects were shown to significantly impact overall and regional particle deposition and introduced inter-subject variability. Significant intra-subject variability in microparticle deposition was also observed in the bi-directional delivery cases. Conclusions: The data from this study suggest that tailoring particle size, combined with a delivery protocol, may provide a unique and pragmatic way to target drugs to the olfactory region. Differences in nasal anatomy among humans can cause variability in particle deposition and need to be considered in any future applications.
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Affiliation(s)
| | - Haribalan Kumar
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Ravi Jain
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Merryn Tawhai
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Shakila Rizwan
- School of Pharmacy, University of Otago, Dunedin, New Zealand
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14
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Wroe S, Parr WCH, Ledogar JA, Bourke J, Evans SP, Fiorenza L, Benazzi S, Hublin JJ, Stringer C, Kullmer O, Curry M, Rae TC, Yokley TR. Computer simulations show that Neanderthal facial morphology represents adaptation to cold and high energy demands, but not heavy biting. Proc Biol Sci 2018; 285:20180085. [PMID: 29618551 PMCID: PMC5904316 DOI: 10.1098/rspb.2018.0085] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 03/13/2018] [Indexed: 12/23/2022] Open
Abstract
Three adaptive hypotheses have been forwarded to explain the distinctive Neanderthal face: (i) an improved ability to accommodate high anterior bite forces, (ii) more effective conditioning of cold and/or dry air and, (iii) adaptation to facilitate greater ventilatory demands. We test these hypotheses using three-dimensional models of Neanderthals, modern humans, and a close outgroup (Homo heidelbergensis), applying finite-element analysis (FEA) and computational fluid dynamics (CFD). This is the most comprehensive application of either approach applied to date and the first to include both. FEA reveals few differences between H. heidelbergensis, modern humans, and Neanderthals in their capacities to sustain high anterior tooth loadings. CFD shows that the nasal cavities of Neanderthals and especially modern humans condition air more efficiently than does that of H. heidelbergensis, suggesting that both evolved to better withstand cold and/or dry climates than less derived Homo We further find that Neanderthals could move considerably more air through the nasal pathway than could H. heidelbergensis or modern humans, consistent with the propositions that, relative to our outgroup Homo, Neanderthal facial morphology evolved to reflect improved capacities to better condition cold, dry air, and, to move greater air volumes in response to higher energetic requirements.
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Affiliation(s)
- Stephen Wroe
- Function, Evolution and Anatomy Research Lab, School of Environmental and Rural Science, University of New England, Armidale, New South Wales 2351, Australia
| | - William C H Parr
- Surgical and Orthopaedic Research Laboratory (SORL), Level 1, Clinical Sciences Bld, Gate 6, Prince of Wales Clinical School, University of New South Wales (UNSW), Avoca St, Randwick, Sydney, New South Wales 2031, Australia
| | - Justin A Ledogar
- Function, Evolution and Anatomy Research Lab, School of Environmental and Rural Science, University of New England, Armidale, New South Wales 2351, Australia
| | - Jason Bourke
- College of Osteopathic Medicine, New York Institute of Technology, Jonesboro, AR 72401, USA
| | - Samuel P Evans
- School of Engineering, University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Luca Fiorenza
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Stefano Benazzi
- Department of Cultural Heritage, University of Bologna, Via degli Ariani 1, Ravenna 48121, Italy
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
| | - Jean-Jacques Hublin
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
| | - Chris Stringer
- Department of Earth Sciences, Natural History Museum, London SW7 5BD, UK
| | - Ottmar Kullmer
- Senckenberg Forschungsinstitut Frankfurt am Main, Abteilung Paläoanthropologie und Messelforschung, Sektion Tertiäre Säugetiere, Senckenberganlage 25, 60325 Frankfurt am Main, Germany
| | - Michael Curry
- Function, Evolution and Anatomy Research Lab, School of Environmental and Rural Science, University of New England, Armidale, New South Wales 2351, Australia
| | - Todd C Rae
- Centre for Research in Evolutionary and Environmental Anthropology, University of Roehampton, London, UK
| | - Todd R Yokley
- Metropolitan State University of Denver, PO Box 173362, Campus Box 28, Denver, CO 80217-3362, USA
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15
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Abstract
Studies on dry human skulls have shown that nasal cavity (NC) morphology varies with eco-geographic factors. These findings have been used by some authors to interpret the facial morphology of Neanderthals. However, respiratory and air-conditioning functions are primarily carried out by the nasal airways (NA), which are delimited by mucosa. The aims of this study were to test whether: (1) NC volume (V) and surface-area-to-volume ratio (SA/ V) are proportional to NA counterparts; (2) measurements for male NC and NA are larger than in females; (3) the centroid size (CS) of a set of landmarks measured on NC provides a reliable proxy for NC V. Head CT (computed tomography) images of adult patients (N = 30) at the University Hospital of Bordeaux were selected retrospectively. NA were defined by segmenting the lumen corresponding to the functional volume. NC was defined by adding to NA the soft tissues delimited by the bones forming the NC. The coordinates of 16 landmarks measured on NC bones were recorded. A rather low correlation was found between NA and NC V while NA SA/V and NC SA/V were not correlated. No significant differences were found between male and female NA and NC measurements. A rather low correlation was found between NC Vand NC CS. If these preliminary results were to be confirmed by future studies, results using NC as a proxy for NA focusing on air-conditioning and respiratory energetics might need to be re-interpreted.
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16
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Bremner FD, Nordström JG. A Case of Synchronised Pupillary and Nasal Cycling: Evidence for a Central Autonomic Pendulum? Neuroophthalmology 2018; 41:241-246. [PMID: 29339957 DOI: 10.1080/01658107.2017.1315144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 03/29/2017] [Accepted: 03/30/2017] [Indexed: 10/19/2022] Open
Abstract
We previously reported that some healthy individuals show alternating anisocoria. We now describe one such individual who also exhibits a classic nasal cycle (alternating periods of nasal congestion and decongestion). We made measurements of his pupil asymmetry and nasal asymmetry at 21 different time points and found that these variables were always synchronised such that greater nasal airflow was invariably found on the same side as the larger pupil. We hypothesise that a common central oscillator may be responsible for co-modulating the sympathetic outflow to both nasal vessels and iris dilator muscles in some healthy individuals.
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Affiliation(s)
- Fion D Bremner
- National Hospital for Neurology & Neurosurgery, London, UK
| | - Jonas Gälldin Nordström
- Husie Health Centre, Department of General Practice, Skane University Hospital, Malmö, Sweden
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17
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ANTOSOVA M, MOKRA D, TONHAJZEROVA I, MIKOLKA P, KOSUTOVA P, MESTANIK M, PEPUCHA L, PLEVKOVA J, BUDAY T, CALKOVSKY V, BENCOVA A. Nasal Nitric Oxide in Healthy Adults – Reference Values and Affecting Factors. Physiol Res 2017; 66:S247-S255. [DOI: 10.33549/physiolres.933680] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Nitric oxide (NO) is an important endogenous mediator with significant role in the respiratory system. Many endogenous and exogenous factors influence the synthesis of NO and its level is significantly changed during the inflammation. Analysis of nasal nitric oxide (nNO) is not validated so far as the diagnostic method. There is a lack of reference values with possible identification of factors modulating the nNO levels. In healthy adult volunteers (n=141) we studied nasal NO values by NIOX MINO® (Aerocrine, Sweden) according to the recommendations of the ATS & ERS. Gender, age, height, body weight, waist-to-hip ratio, FEV1/FVC, PEF and numbers of leukocytes, eosinophils, basophils and monocytes were studied as potential variables influencing the levels of nNO. The complexity of the results allowed us to create a homogenous group for nasal NO monitoring and these data can be used further as the reference data for given variables. Because of significant correlation between nNO and exhaled NO, our results support the “one airway – one disease” concept. Reference values of nasal NO and emphasis of the individual parameters of tested young healthy population may serve as a starting point in the non-invasive monitoring of the upper airway inflammation.
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Affiliation(s)
- M. ANTOSOVA
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
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18
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White DE, Nates RJ, Bartley J. Model identifies causes of nasal drying during pressurised breathing. Respir Physiol Neurobiol 2017; 243:97-100. [PMID: 28606767 DOI: 10.1016/j.resp.2017.06.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Revised: 04/25/2017] [Accepted: 06/07/2017] [Indexed: 11/19/2022]
Abstract
Patients nasally breathing pressurised air frequently experience symptoms suggestive of upper airway drying. While supplementary humidification is often used for symptom relief, the cause(s) of nasal drying symptoms remains speculative. Recent investigations have found augmented air pressure affects airway surface liquid (ASL) supply and inter-nasal airflow apportionment. However the influence these two factors have on ASL hydration is unknown. The purpose of this study is to determine how ASL supply and airflow apportionment affect ASL hydration status for both ambient and pressurised air breathing conditions. This is done by modifying and adapting a nasal air-conditioning and ASL supply model. Model predictions of change in inter-nasal airflow apportionment closely follow in-vivo results and demonstrate for the first time abnormal ASL dehydration occurring during augmented pressure breathing. This work quantitatively establishes why patients nasal breathing pressurised air frequently report adverse airway drying symptoms. The findings from this investigation demonstrate that both nasal airways simultaneously experience severe ASL dehydration during pressurised breathing.
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Affiliation(s)
- David E White
- BioDesign Lab, School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand.
| | - Roy J Nates
- BioDesign Lab, School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand.
| | - Jim Bartley
- Department of Surgery, University of Auckland, Auckland, New Zealand.
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19
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Kahana-Zweig R, Geva-Sagiv M, Weissbrod A, Secundo L, Soroker N, Sobel N. Measuring and Characterizing the Human Nasal Cycle. PLoS One 2016; 11:e0162918. [PMID: 27711189 PMCID: PMC5053491 DOI: 10.1371/journal.pone.0162918] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 08/30/2016] [Indexed: 11/18/2022] Open
Abstract
Nasal airflow is greater in one nostril than in the other because of transient asymmetric nasal passage obstruction by erectile tissue. The extent of obstruction alternates across nostrils with periodicity referred to as the nasal cycle. The nasal cycle is related to autonomic arousal and is indicative of asymmetry in brain function. Moreover, alterations in nasal cycle periodicity have been linked to various diseases. There is therefore need for a tool allowing continuous accurate measurement and recording of airflow in each nostril separately. Here we provide detailed instructions for constructing such a tool at minimal cost and effort. We demonstrate application of the tool in 33 right-handed healthy subjects, and derive several statistical measures for nasal cycle characterization. Using these measures applied to 24-hour recordings we observed that: 1: subjects spent slightly longer in left over right nostril dominance (left = 2.63 ± 0.89 hours, right = 2.17 ± 0.89 hours, t(32) = 2.07, p < 0.05), 2: cycle duration was shorter in wake than in sleep (wake = 2.02 ± 1.7 hours, sleep = 4.5 ± 1.7 hours, (t(30) = 5.73, p < 0.0001). 3: slower breathing was associated with a more powerful cycle (the extent of difference across nostrils) (r = 0.4, p < 0.0001), and 4: the cycle was influenced by body posture such that lying on one side was associated with greater flow in the contralateral nostril (p < 0.002). Finally, we provide evidence for an airflow cycle in each nostril alone. These results provide characterization of an easily obtained measure that may have diagnostic implications for neurological disease and cognitive state.
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Affiliation(s)
- Roni Kahana-Zweig
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Maya Geva-Sagiv
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Aharon Weissbrod
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Lavi Secundo
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Nachum Soroker
- Loewenstein Rehabilitation Hospital, Ra’anana, 43100, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, 69978, Israel
| | - Noam Sobel
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, 76100, Israel
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20
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White DE, Bartley J, Shakeel M, Nates RJ, Hankin RKS. Nasal airway responses to nasal continuous positive airway pressure breathing: An in-vivo pilot study. J Biomech 2016; 49:1887-1890. [PMID: 27173595 DOI: 10.1016/j.jbiomech.2016.04.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 04/25/2016] [Accepted: 04/27/2016] [Indexed: 11/17/2022]
Abstract
The nasal cycle, through variation in nasal airflow partitioning, allows the upper airway to accommodate the contrasting demands of air conditioning and removal of entrapped air contaminants. The purpose of this study was to investigate the influence of nasal continuous positive airway pressure (nCPAP) breathing has on both nasal airflow partitioning and nasal geometry. Using a custom-made nasal mask, twenty healthy participants had the airflow in each naris measured during normal nasal breathing followed by nCPAP breathing. Eight participants also underwent magnetic resonance imaging (MRI) of the nasal region during spontaneous nasal breathing, and then nCPAP breathing over a range of air pressures. During nCPAP breathing, a simultaneous reduction in airflow through the patent airway together with a corresponding increase in airway flow within the congested nasal airway were observed in sixteen of the twenty participants. Nasal airflow resistance is inversely proportional to airway cross-sectional area. MRI data analysis during nCPAP breathing confirmed airway cross-sectional area reduced along the patent airway while the congested airway experienced an increase in this parameter. During awake breathing, nCPAP disturbs the normal inter-nasal airflow partitioning. This could partially explain the adverse nasal drying symptoms frequently reported by many users of this therapy.
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Affiliation(s)
- David E White
- School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand.
| | - Jim Bartley
- Department of Otolaryngology - Head and Neck Surgery, Counties District Health Board, Manukau, Auckland, New Zealand; Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Muhammad Shakeel
- Department of Otolaryngology - Head and Neck Surgery, Counties District Health Board, Manukau, Auckland, New Zealand
| | - Roy J Nates
- School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand
| | - Robin K S Hankin
- School of Engineering, Computer and Mathematical Sciences, Auckland University of Technology, Auckland, New Zealand
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