Evaluation of nasal patency: comparison of patient and clinician assessments with rhinomanometry

Do Mean Values of the Peak Inspiratory Nasal Flowmeter Vary According to the Severity, Direction and Type of Nasal Septum Deviation?

The aim is to investigate the contribution of the PNIF test in daily clinical practices in the objective evaluation of the early postoperative functional results of septoplasty and the effect of the severity, direction, and type of nasal septum deviation on mean PNIF values. Nasal septum deviation (NSDs) of the cases were grouped according to the Mladina classification and the severity of NSDs. An objective evaluation of the nasal airway was conducted via a peak flowmeter device in the preoperative and postoperative first month. When examining the mean PNIF values according to genders, it was observed that the values determined in male cases in the preoperative and postoperative period were higher. In the intragroup evaluation performed according the Mladina classification, a statistically significant increase was observed in the preoperative and postoperative PNIF values of the cases in Types 1-4. In the intragroup evaluation performed according to the severity of NSD, there was a significant increase in the preoperative and postoperative PNIF values of the mild and moderate cases. When comparing the preoperative and postoperative PNIF values of the groups in terms of the severity of NSD, it was observed that there was a significant difference. The PNIF can be used in routine clinical practices to evaluate the septoplasty results objectively. In the evaluation of functional results, the change in the mean PNIF values may also vary according to the direction and severity of septum deviation and the Mladina classification other than age, gender and ethnic origin.

Role of Peak Nasal Inspiratory Flow for Measuring the Effectiveness of Surgery in Children with Adenoidal Hypertrophy

Objective

Nasal airway obstruction in children is a frequent problem in otolaryngology practice. Adenoidal hypertrophy (AH) is the most common pathology in childhood that requires surgery. Nasal patency can be evaluated by subjective and objective methods. Unlike other methods, peak nasal inspiratory flow (PNIF) is portable and easy to perform. The need for patient compliance is the most important disadvantage of this method. We aimed to analyze the significance of PNIF for measuring the effectiveness of adenoidectomy as well as to compare PNIF with other subjective methods.

Methods

Two-hundred forty-five (245) patients aged between six and 11 years were evaluated. Seventy-seven (77) of them formed the study group and 168 formed the control group. Pre and post-surgery PNIF measurements, adenoid scores, and simple visual analog scale (sVAS) were recorded.

Results

The average PNIF value has significantly increased to 70.65 L/min from 33.02 L/min after adenoidectomy (p<0.01). The average PNIF value was 71.66 L/min in control subjects. High PNIF values were significantly correlated with low sVAS and adenoid scores postoperatively in the study group as compared with those of preoperative data (p<0.01).

Conclusions

PNIF has a satisfying correlation with nasal examination findings and other subjective methods to evaluate nasal obstruction and may provide unique and complementary information helpful for evaluating and improving the effects of adenoidectomy in children.

Effect of the Use of Intranasal Spray of Essential Oils in Patients with Perennial Allergic Rhinitis: A Prospective Study

INTRODUCTION

Among allergic rhinitis (AR) symptoms, nasal obstruction particularly affects the quality of life. Antihistamines and intranasal corticosteroids are the most frequently prescribed symptomatic drugs, but their efficacy is often incomplete. Essential oils (EO) have shown an anti-inflammatory effect and potential in treating patients with AR. The aim of this study was to evaluate the effectiveness of a hypertonic EO-based nasal spray on perennial AR (PAR) symptoms.

METHODS

This prospective, open-label, non-randomized, multicentric trial included 43 patients with PAR sensitized to mites, not controlled for more than a year. All were treated with Puressentiel® Respiratory-Decongestant Nasal Spray for 30 days. Their usual treatment remained unchanged during the study period. Before and after treatment, each participant filled out a rhinitis questionnaire, the Allergic Rhinitis Control Test (ARCT). A nasal inspiratory peak flow (NIPF) was performed.

RESULTS

The mean ARCT was 16.4 and 20.5 at D0 and D30, respectively (p < 0.001); the mean increase between D0 and D30 was 4.1 (p < 0.001). The proportion of patients with controlled rhinitis after 30 days of treatment was 69.8 versus 14% before treatment (p < 0.001). The mean NIPF was 86.5 L/min and 105.1 L/min at D0 and D30, respectively (p < 0.001); the mean increase between D0 and D30 was 18.5 L/min.

CONCLUSION

A hypertonic EO-based nasal spray could be a new and natural option in the management of PAR. It could also be used as an add-on therapy when nasal symptoms are not fully controlled.

Mometasone furoate is not superior to saline for chronic rhinitis in the elderly

Introduction

Prevalence of diseases associated with ageing is rising; among these are the rhinologic problems. Chronic rhinitis appears as one of the most common worrisome nasal disorders in this age group. At the same time, the allergic form diminishes because of the immunosenescence.

Objective

This study aimed to evaluate the effect of a corticosteroid nasal spray (mometasone furoate) over nasal patency and the severity of rhinitis and its impacts on quality of life as compared with the saline nasal spray.

Methods

This open label-trial randomized subjects ≥60y with chronic rhinitis (allergic and nonallergic rhinitis) with mometasone spray 100mcg/d and isotonic saline nasal spray or saline alone for two weeks. The primary endpoint was the improvement in nasal patency evaluated by the peak nasal inspiratory flow (PNIF). Secondary outcomes included the severity of symptoms and the quality of life assessed by a visual analogic scale (VAS) and the sinonasal outcome test (SNOT-22), respectively.

Results

Forty patients underwent randomization, in equal number in each group of treatment, either with allergic (AR) and nonallergic rhinitis (NAR). At week 2, the mean PNIF score was 79.5 in the corticosteroid (CE) plus saline group and 82.0 in the saline group (p = 0.37). Also, SNOT-22 and VAS were not improved with the addition of mometasone furoate.

Conclusions

Treatment with mometasone furoate nasal spray plus isotonic saline is not superior to saline alone in elderly patients with rhinitis in respect of improving nasal patency, quality of life, and reducing the intensity of symptoms.

Trial registration

The trial is registered at the Brazilian Clinical Trials Registry (ReBEC) #RBR-498bnq. Registered 05 July 2017.

Unilateral and Bilateral PNIF in Quality Control of Nasal Septal Surgery

The aim of this study was to explore the usefulness of unilateral, combined unilateral (left + right), and bilateral peak nasal inspiratory flow (PNIF) measurements in assessing the results of nasal septal surgery. Nasal obstruction was recorded subjectively and objectively before and 4 months after nasal septoplasty using a visual analogue scale (VAS) and a PNIF meter. Nasal septoplasty (58 patients) and septoplasty with turbinoplasty (68 patients) were performed on 126 patients (85 males; 41 females) with a mean age of 32.8 years. The results showed a significant improvement in VAS scores, as well as unilateral, combined unilateral, and bilateral PNIF values after both septoplasty and septoplasty with turbinoplasty. Septoplasty with turbinoplasty showed better improvement in VAS and PNIF scores than septoplasty alone and this was significant for bilateral PNIF scores. The best unilateral pre- and postoperative correlations between VAS and PNIF measurements were found using the lower of the two unilateral PNIF scores, irrespective of side. In the total material, VAS/PNIF correlations were mostly significant, but weak (all r<0.30). We found VAS and PNIF to be useful instruments in reporting results of surgery. The weak correlations between VAS and PNIF measurements suggest that these subjective and objective instruments may target different aspects of nasal obstruction.

How Good are Patients at Determining which Side of the Nose is More Obstructed? A Study on the Limits of Discrimination of the Subjective Assessment of Unilateral Nasal Obstruction

Background

The subjective sensation of nasal obstruction is of great importance to the patient and surgeon because it is this symptom that causes the patient to present for investigation and treatment. Although there are several studies in the literature looking at the correlation (or lack of correlation) between objective and subjective measures of nasal obstruction, there is no information on the minimum objective change in obstruction measured as nasal airway resistance or flow, which can be detected by a patient. The aim of this study was to measure the minimum difference in unilateral airflow that can be reliably detected by a patient.

Methods

Sixty participants with a common cold were recruited. One hundred twenty unilateral measurements of objective and subjective nasal obstruction were obtained using the technique of posterior rhinomanometry and a 100-mm visual analog scale (VAS).

Results

Seventy-seven percent of the participants correctly discriminated between the high- and low-flow nasal passages using the VAS. Ninety-five percent of subjects correctly discriminated on the VAS between the high- and low-flow nasal passages when the difference in flow between the nasal passages was at least 100 cm3/s.

Conclusion

This study provides new knowledge about the limits of subjective sensation of nasal obstruction. At a level of 100 cm3/s difference in unilateral nasal flow, 95% of subjects with acute rhinitis can correctly identify the more obstructed nasal passage when using a VAS. With smaller differences in unilateral flow, the percentage of correct responses declines rapidly toward 50% as expected by chance alone.

Evaluation of Patient Satisfaction After Nasal Septoplasty Operation Using Peak Nasal Inspratuar Flow and Nasal Obstruction Symptom Score Questionare

BACKGROUND

The purpose of this study was to investigate the usefulness of the peak nasal inflamatuar flow (PNIF) and Nasal Obstruction Symptom Score (NOSE) questionnaire in the diagnosis and follow-up of nasal septum deviation surgery.

METHODS

Sixty patients diagnosed with nasal septum deviation were included in the study. Nasal Obstruction Symptom Score scales of patients, PNIF and is measured preoperatively and 14 days after surgery.

RESULTS

Preoperative NOSE scores were 14.9 ± 2.7 and PNIF scores were 129.6 ± 15.5 L/min in study group. Postoperatively NOSE scores were 7.9 ± 1.8 and PNIF scores were 154.2 ± 9.2 L/min in study group. Nasal Obstruction Symptom Score scores were 3.3 ± 2.3 and PNIF scores were 169.3 ± 13.5 L/min in control group.

CONCLUSION

Anterior and anteroposteriorly located nasal septum deviation (NSD) had statistically higher degrees of NOSE scores and lower levels of PNIF scores. Posterior located NSD PNIF scores changed postoperatively but NOSE scores do not change statistically. There was a statistically significant correlation in Pearson correlation analysis between NOSE and PNIF scores. The authors recommend using PNIF and NOSE scores in NSD patients.

Measuring Nasal Obstruction

The nose and the nasal airway is highly complex with intricate 3-dimensional anatomy, with multiple functions in respiration and filtration of the respired air. Nasal airway obstruction (NAO) is a complex problem with no clearly defined "gold-standard" in measurement. There are 3 tools for the measurement of NAO: patient-derived measurements, physician-observed measurements, and objective measurements. We continue to work towards finding a link between subjective and objective nasal obstruction. The field of evaluation and surgical treatment for NAO has grown tremendously in the past 4-5 decades and will continue to grow as we learn more about the pathophysiology and treatment of nasal obstruction.

Measurements of nasal airflow and patency: a critical review with emphasis on the use of peak nasal inspiratory flow in daily practice

Objective measures can be used to assist the clinician to diagnose and treat nasal obstruction and also to quantify nasal obstruction in research. Objective measurements of nasal obstruction are as important as objective measurements of lung function. peak nasal inspiratory flow (PNIF), acoustic rhinometry (AR) and rhinomanometry (RM), with their specific peculiarity, assess different aspects of nasal obstruction. From the studies available in the literature, it seems that these methods roughly correlate with each other and that all of them can be alternatively utilized very well in research as well as in clinical practice. This review describes the various methods that can be used to measure nasal patency, airflow and resistance, mainly peak nasal inspiratory flow, rhinomanometry and acoustic rhinometry. PNIF has been demonstrated to be reproducible and as good an indication of objective nasal patency as formal rhinomanometry and has the advantage to be cheap, simple and suitable for serial measurements and for home use even in the paediatric population. PNIF normative data are available for children, adults and elderly subjects, and the availability of unilateral PNIF normal values allows evaluation of nasal sides separately. Just as in the lower airways, objective and subjective evaluation gives different information that together optimizes the diagnosis and the treatment of our patients. We argue that PNIF should be used regularly in every outpatient clinic that treats patients with nasal obstruction.

Will Septal Correction Surgery for Deviated Nasal Septum Improve the Sense of Smell? A Prospective Study

Background and Objectives. Nasal obstruction due to deviated nasal septum is a common problem bringing a patient to an otorhinolaryngologist. Occasionally, these patients may also complain of olfactory impairment. We proposed to study the effect of septal deviation on the lateralised olfactory function and the change in olfaction after surgery of the septum (septoplasty). Methods. Forty-one patients with deviated nasal septum were evaluated for nasal airflow, olfactory score, and nasal symptomatology. Septoplasty was done under local anesthesia. Pre- and postoperative olfactory scores, airflow and olfactory scores, and nasal symptomatology and olfactory scores were compared and correlated. Results. The range of preoperative composite olfactory score (COS) on the side of septal deviation was 4-14 (mean 7.90 ± 2.234) and on the nonobstructed side was 9-18 (mean 14.49 ± 2.378). Severity of deviated nasal septum and preoperative COS of diseased side were correlated and the correlation was found to be significant (rho = -0.690, p = 0.000 (<0.001)). The preoperative mean COS (7.90 ± 2.234) was compared with the postoperative mean COS (12.39 ± 3.687) and the improvement was found to be statistically significant (p = 0.000 (<0.001)). Conclusion. We found improvement in olfactory function in 70.6% patients after surgery, no change in 20.1%, and reduced function in 7.6%. With the limitation of a small sample size and a potential repeat testing bias, we would conclude that correction of nasal septal deviation may lead to improvement in sense of smell.

Normal range of peak nasal inspiratory flow and its role in nasal septal surgery

Nasal obstruction can be evaluated by objective and subjective methods. We sought to determine normative peak nasal inspiratory flow meter (PNIF) measurements of a healthy population in Turkey and to investigate the importance of PNIF in surgery for nasal septal deviation as well as to investigate the correlation of PNIF with subjective methods. In a total of 269 patients, 50 patients underwent septoplasty and 219 control subjects were enrolled in the study. Data on preoperative and postoperative PNIF measurements, nasal septal indices, and subjective measurements (visual analogue scale, VAS) were recorded. Mean PNIF value was 137.8 L/min in control subjects. Postoperative PNIF, VAS, and nasal septal index data were statistically significantly higher in the study group as compared with those of preoperative data. We found PNIF, VAS, and nasal septal indices of the control group to be consistent with postoperative data and to be higher than preoperative data of the study group. We identified a normal PNIF range for the healthy Turkish population and we saw that the data were compatible with VAS scores. PNIF seems to be a very effective method in the evaluation of nasal obstruction and in deciding operation.

Evaluation of a nasal surgical questionnaire designed for monitoring surgical outcomes and comparing different techniques

OBJECTIVE

This study evaluated a nasal surgical questionnaire designed for monitoring surgical outcomes and comparing different techniques.

METHODS

Eighty-three healthy volunteers answered the same questionnaire twice with a minimum interval of five weeks. Three visual analogue scale items were used to assess nasal obstruction during the day, at night and during exercise. Respondents rated nasal obstruction severity by marking on a 10 cm line, with scores ranging from 0 to 100 (measured in millimetres). Other nasal symptoms, considered secondary outcomes, were graded using four-point Likert scales.

RESULTS

Mean visual analogue scale scores for nasal obstruction severity experienced during the day, at night and during exercise at initial assessment were 9.99, 12.95 and 11.67, respectively. Thirty-eight per cent of scores indicated no obstruction (scores of 0), 47 per cent indicated mild obstruction (scores 1-30), 13 per cent indicated moderate obstruction (scores 31-70) and 2 per cent indicated severe obstruction (scores 71-100). Males had higher scores than females. The scores for the first and second assessment did not differ, except at night for obstruction in allergic individuals which was considered clinically unimportant.

CONCLUSION

The questionnaire reliably assesses nasal symptoms and may be useful for prospective studies of nasal surgery.

Nasal peak inspiratory and expiratory flow measurements for assessing nasal obstruction in allergic rhinitis

BACKGROUND

Although nasal peak flow measurements have been proposed as a simple alternative method to assess nasal patency, which of nasal peak expiratory flow or nasal peak inspiratory flow (NPEF/NPIF) or the peak expiratory flow index or peak inspiratory flow index (PEFI/PIFI; the ratios between nasal and oral PEF or nasal and oral PIF, respectively) is the more accurate method is unclear. The aim of this study was to evaluate the correlation between NPEF, NPIF, PEFI, and PIFI, and blocked nose score (BNS) and mucociliary clearance time (MCCT) in diagnostic and follow-up assessments.

METHODS

Ninety-nine allergic rhinitis (AR) patients were treated with 220 micrograms once daily of intranasal triamcinolone acetonide for 28 days. BNS, NPEF, NPIF, PEFI, and PIFI and MCCT were used to evaluate treatment outcome. Correlations of initial visit scores and score changes after treatment between peak flow rates and BNSs and MCCTs were analyzed.

RESULTS

All nasal symptoms, peak flows, and MCCTs showed statistically significant improvements after the nasal steroid treatment. PEFI showed the best negative correlation with BNS and MCCTs, followed by PIFI, NPEF, and NPIF. Nasal peak flows showed better correlations with MCCTs than BNSs. Mean changes of peak flow rates between visits showed better correlation with BNSs and MCCTs than absolute values of peak flow rates at the initial visit.

CONCLUSION

Among nasal peak flow measurements, PEFI is the most appropriate objective tool for assessing nasal patency in AR. Peak flows can indicate underlying mucosal inflammation and are more sensitive to assess score changes after treatment than cross-sectional assessment at the initial visit.

The clinical value of peak nasal inspiratory flow, peak oral inspiratory flow, and the nasal patency index

OBJECTIVES/HYPOTHESIS

The aim of this study was to ascertain the most reliable objective measurement for the assessment of nasal patency by investigating the relationship between peak nasal inspiratory flow, peak oral inspiratory flow, and the nasal patency index in relation to the patient's subjective perception regarding nasal obstruction.

STUDY DESIGN

Prospective cohort study.

METHODS

This study included 131 volunteers of both genders, aged 18 years or older, with or without nasal symptoms, who were able to give informed consent, completed the study protocol, and could speak and write Dutch fluently. Peak nasal inspiratory flow and peak oral inspiratory flow were performed and nasal patency index was computed. The results were evaluated and compared with the subjective perception of nasal passage, using the validated Nasal Obstruction Symptom Evaluation scale and visual analog scale for nasal passage.

RESULTS

Our study showed that peak nasal inspiratory flow, nasal patency index and nasal patency visual analog scale correlate with the Nasal Obstruction Symptom Evaluation scale in contrast to peak oral inspiratory flow. Peak nasal inspiratory flow and nasal patency index also showed significant association with the Nasal Obstruction Symptom Evaluation scale after adjustment for confounders.

CONCLUSIONS

Peak nasal inspiratory flow is the most reliable method for the assessment of nasal patency. It is quick, inexpensive, and easy to perform, and correlates significantly with the subjective feeling of nasal obstruction. There is no clinical need to measure peak oral inspiratory flow or to calculate the nasal patency index in the evaluation of nasal patency.

LEVEL OF EVIDENCE

4

Effect of laser treatment on olfactory dysfunction

Olfactory disorders are not rare and affect quality of life in patients. The purpose of our study was to evaluate the outcomes of an outpatient-based diode laser inferior turbinate reduction (ITR) in otherwise therapy-refractory olfactory disorder. In a prospective clinical investigation, 20 patients (7 male, 13 female, mean age 53.2 ± 15.34) with olfactory disorder and 10 patients (8 male, 2 female, mean age 52.5 ± 17.55) without olfactory disorder underwent ITR under videoendoscopic control with a continuous diode laser in "contact" mode after topical anesthetic preparation. Treatment efficiency was assessed before and 2 months after surgery. Subjective nasal airflow (NA) and the olfactory function were rated by means of visual analogue scales (VAS). Olfactory function was assessed using the "Sniffin' Sticks" test battery. VAS showed very low median values for intraoperative pain (0) [0-1.20] and high postoperative patient satisfaction (8) [5-9]. After 2 months there was no significant improvement of objective olfactory function as measured by the TDI score (threshold, discrimination and identification). The VAS displayed a slight significant improvement in the group of patients with olfactory disorder from 2.95 to 3.65 (P = 0.04). After 2 months, NA data revealed a statistically significant improvement of subjective VAS from 5.05 to 6.25 (P < 0.0005) and of objective NA from 353.77 to 443.50 (P = 0.007) as measured by rhinomanometry in both groups. Outpatient diode laser ITR represents an effective option providing recovery by NA improvement but not a significant improvement of the olfactory function.

Diagnostic tools in Rhinology EAACI position paper

This EAACI Task Force document aims at providing the readers with a comprehensive and complete overview of the currently available tools for diagnosis of nasal and sino-nasal disease. We have tried to logically order the different important issues related to history taking, clinical examination and additional investigative tools for evaluation of the severity of sinonasal disease into a consensus document. A panel of European experts in the field of Rhinology has contributed to this consensus document on Diagnostic Tools in Rhinology.

Gastroesophageal reflux disease and chronic sinusitis: in search of an esophageal-nasal reflex

BACKGROUND

This study was performed to explore whether or not a neural reflex linking the esophagus and the nasal airway exists, as a pathogenic mechanism accounting for the association between gastroesophageal reflux (GER) disease and chronic rhinosinusitis (CRS). A prospective trial of healthy human volunteers was performed.

METHODS

Ten healthy volunteers without GER or sinonasal disease were investigated using an acid infusion challenge test. Normal saline and hydrochloric acid were infused into the lower esophagus through an esophageal manometry catheter. Nasal responses in symptom score, nasal inspiratory peak flow, and mucus production were analyzed after the esophageal challenge.

RESULTS

A tendency for an increase in nasal mucus production was observed after esophageal stimulation with both normal saline and HCl. This returned to baseline level 45 minutes after the acid infusion. A similar trend was also observed with the measurements of nasal symptom scores and, to a lesser extent, nasal inspiratory peak flow.

CONCLUSION

These results support the possibility that a neural reflex exists between the esophagus and the paranasal sinuses via the vagus nerve. If indeed present, the reflex-mediated rhinitis derived from this neuropathic inflammation may contribute to the development of CRS in patients with GER. Further study is required to define the relationship between GER and CRS.

Inferior turbinate surgery for nasal obstruction in allergic rhinitis after failed medical treatment

BACKGROUND

Allergic rhinitis is a highly prevalent disease that results from an IgE-mediated hypersensitivity reaction of the nasal mucosa to inhaled allergens. It is primarily treated by allergen avoidance and medical treatment, but when these measures fail to control symptoms then surgery to the inferior turbinates of nose is often performed. It is unclear whether these procedures are beneficial in the long term or indeed whether the risks outweigh the benefits.

OBJECTIVES

To assess the effectiveness of inferior turbinate surgery on unrelieved or partially relieved nasal obstruction in patients after maximal medical treatment of proven allergic rhinitis, to compare the results using different surgical techniques and to measure short and long-term results.

SEARCH STRATEGY

We searched the following databases from their inception for published, unpublished and ongoing trials: the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 2); PubMed; EMBASE; CINAHL; LILACS; KoreaMed; IndMed; PakMediNet; CAB Abstracts; Web of Science; BIOSIS Previews; CNKI; mRCT (Current Controlled Trials); ClinicalTrials.gov; ISRCTN; ICTRP (International Clinical Trials Registry Platform); Cambridge Scientific Abstracts; Google and additional sources for published and unpublished trials. We modelled subject strategies for databases on the search strategy designed for CENTRAL. The date of the most recent search was 6 July 2010.

SELECTION CRITERIA

Randomised controlled trials of inferior turbinate surgery versus continued medical treatment for proven allergic rhinitis, or comparisons between one technique of inferior turbinate surgery versus another technique, after maximal medical treatment.

DATA COLLECTION AND ANALYSIS

Both authors independently screened the search results and assessed the full text of potentially relevant studies. We attempted to contact trial authors for additional information.

MAIN RESULTS

There were no studies that fulfilled the inclusion criteria of the review.

AUTHORS' CONCLUSIONS

This review highlights the need for randomised controlled trials to evaluate the role of inferior turbinate surgery for nasal obstruction in allergic rhinitis after failed medical treatment. Future trials needs to be rigorous in design and delivery, separate adults from paediatric patients, not combine allergic with non-allergic patients and last long enough to determine long-term results and complications.

Sensation of nasal patency compared to rhinomanometric results after septoplasty

The primary aim of the present study was to investigate the relationship between the subjective sensation of nasal airflow resistance, the rhinoscopic findings and the objective measures of nasal obstruction in patients followed up after septoplasty. A further goal was to determine which of the above modalities is most suitable for assessment of the severity of nasal obstruction and which best indicates the need for surgery. 86 patients who had previously undergone septoplastic surgery were recruited. Objective and subjective measures of nasal obstruction were recorded by using active anterior rhinomanometry, rhinoscopy and a visual analogue scale. The Spearman rank order correlation model revealed a significant correlation between the VAS score and the airway resistance of the more obstructed nasal cavity (r = 0.24); furthermore, between the VAS score and rhinoscopic findings (r = 0.35). By applying the generalized linear model, we also found significant relation between the VAS score and the rhinomanometric data, and between the rhinoscopic findings and the airway resistance of the more obstructed nasal cavity (p = 0.02). The correlation between the subjective sensation of nasal airflow resistance, the rhinoscopic findings, and the rhinomanometric data proved to be significant, but weak even in the group of patients that underwent septoplasty. Every postoperative complaint should therefore be evaluated carefully. Rhinomanometry is an appropriate diagnostic tool with which to determine the measure of obstruction caused by nasal pathological factors. It is suitable for making objective the patients' complaints. Rhinoscopy, beyond the assessment of the degree of obstruction, is capable of analysis of its cause. The decision as to the need for surgery should be based on rhinoscopy, or nasal endoscopy, and can be supported by pathologically elevated resistance of the more obstructed nasal cavity.

Endoscopic diode laser polypectomy and high-dose intranasal steroids in recurrent nasal polyposis

BACKGROUND

The aim of this clinical investigation was to determine the outcomes of an outpatient videoendoscopic diode laser polypectomy (DLPE) and subsequent topical high-dose corticosteroid application in chronic rhinosinusitis with recurrent nasal polyposis (NP).

METHODS

After ineffective revision sinus surgery and prolonged mometasone furoate application, 19 consecutive mild and moderate NP patients suffering from nasal obstruction (NO) and olfactory dysfunction (OD) were prospectively entered into the study to undergo DLPE under topical anesthesia. Beginning 1 week postoperatively, 250 microg of beclomethasone dipropionate aerosol spray (BDPAS) was self-administered into each nostril twice a day. Treatment efficacy was assessed after 1, 6, and 12 weeks and at quarterly long-term follow-ups based on objective parameters (videoendoscopic photodocumentation and rhinomanometry) and subjective evaluation of NO, OD, and satisfaction (visual analog scales [VASs]).

RESULTS

VASs indicated very low values for intraoperative pain and discomfort and high postoperative satisfaction. After 6 weeks, subjective and objective data revealed a significant improvement of NO and OD (p < 0.0005). Topical BDPAS application was well tolerated. At a median follow-up of 32 months (range, 1-4 years), 21% of the patients developed NP disappearance, 53% had a stable disease, and 26% had a progressive disease.

CONCLUSION

In therapy-refractory NP, endonasal DLPE represents a minimally invasive, symptom-oriented, safe and easily reapplicable outpatient treatment option that provides effective improvement of NO and OD. Compared with the pre-DLPE period, the proposed long-term quarterly follow-up combined with high-dose topical BDPAS application might reduce or delay the need for major surgery and appears to be suitable for disease control.

Rhinitis medicamentosa: therapeutic effect of diode laser inferior turbinate reduction on nasal obstruction and decongestant abuse

BACKGROUND

The purpose of this study was to evaluate long-term outcomes of an outpatient-based diode laser inferior turbinate reduction (ITR) in therapy-refractory rhinitis medicamentosa (RM).

METHODS

In a prospective clinical investigation, 42 consecutive RM patients underwent videoendoscopic ITR with a diode laser after topical anesthetic preparation. Intra- and perioperative details were recorded including the occurrence of bleeding, crusting, pain, or discomfort. Treatment efficiency was assessed by follow-ups 1 and 6 weeks as well as 6 and 12 months after surgery. Subjective pre- and posttherapeutic nasal airflow (NA) and patient satisfaction were rated on visual analog scales (VASs). Assessment of the long-term objective clinical effectiveness was based on rhinomanometry, IT photodocumentation, and the recurrent need for decongestants.

RESULTS

Preoperative addiction to decongestants lasted 5 +/- 2 years (mean +/- SD). There was no major bleeding requiring nasal packing, and there were no other perioperative complications. Postoperative edema disappeared within the 1st week and crusting within 6 weeks after surgery. VAS was characterized by very low values for intraoperative pain and discomfort and high postoperative patient satisfaction. After 6 months, NA data revealed a significant improvement of subjective VAS and objective rhinomanometry (250.4-413.9 cm3/s inspiration at 150 Pa). A total of 88% of patients managed to successfully stop decongestant abuse after 6 months (74% after 1 year).

CONCLUSION

In therapy-refractory RM, outpatient diode laser ITR of hyperplastic IT represents a highly effective, safe, and well-tolerated treatment option that provides long-lasting recovery by markedly improving NA and stopping addiction to nasal decongestants.

Effects of buffered 2.3%, buffered 0.9%, and non-buffered 0.9% irrigation solutions on nasal mucosa after septoplasty

A prospective randomized study was designed to compare the effect of different irrigation solutions on mucociliary clearance and nasal patency and to compare the limitations of the used solutions, such as nasal burning by a visual analog scale. Forty-five patients who underwent septoplasty were divided into three groups postoperatively. Each group was administered with 2.3% buffered hypertonic seawater, buffered isotonic saline solution and non-buffered isotonic saline, respectively, as irrigation fluid. Saccharine test and acoustic rhinometer were used to determine mucociliary activity and nasal patency. Patients were asked about the burning sensation using a 10-cm visual analog scale. There was no significant difference in saccharine clearance time (SCT) on the 5th postoperative day between the three groups (P = 0.07). On the 20th day, there was a significant difference in SCT between the hypertonic buffered seawater group and non-buffered isotonic saline (P = 0.003). Buffered hypertonic seawater improved nasal airway patency more than the buffered isotonic saline (P = 0.004). Buffered hypertonic solutions used after endonasal surgery have been advantageous for both mucociliary clearance and postoperative decongestion.

Modified Glatzel mirror test reproducibility in the evaluation of nasal patency

The Glatzel Mirror (GM) is used to evaluate nasal patency. Validation studies are not available in the literature. This paper aims to verify the GM test reproducibility and the correlation between the intra-subject condensation area and nasal patency subjective perception.

Methods

This is a prospective study. 25 subjects were evaluated with the GM for five consecutive minutes, every half an hour for 4 hours; every day, beginning in the early afternoon, every Thursday for five consecutive weeks. A visual analogue scale was used to evaluate nasal patency perception in all periods.

Results

The total correlation coefficient (right + left areas) found between the condensation area and the subjective perception was r = 0.04 (p = 0.37). On the left side it was r = 0.08 (p = 0.09) and on the right side r = 0.05 (p = 0.28). The mean unilateral variation coefficient was less than 15% and the total was less than 12%, regardless of the time period interval between test and re-test.

Conclusion

We did not observe any significant correlation between the subjective perception of breathing and the condensation area. Unilateral variability was higher than the total (right + left area) and the test variability was the same between the different time periods of measurements.

Evidence-based recommendations regarding the differential diagnosis and assessment of nasal congestion: using the new GRADE system

Nasal congestion is an important symptom in nasal pathology and can be defined as an objective restriction of nasal cavity airflow because of mucosal pathology and/or increased mucus secretion (excluding anatomical variants). Using the new Grading Recommendations Assessment, Development and Evaluation system, evidence-based recommendations are made that will encompass different clinical questions regarding diagnostic modalities of nasal congestion: (i) their usefulness in assessment of presence and severity of congestion; (ii) their usefulness in assessment of etiological pathology responsible for congestion; and (iii) their usefulness in follow up and treatment effectiveness evaluation of nasal congestion.

A reprodutibilidade do espelho de Glatzel modificado na aferição da permeabilidade nasal

O espelho de Glatzel (EG) é utilizado para a avaliação da permeabilidade nasal. Estudos de validação inexistem na literatura. Este estudo teve por objetivos verificar a reprodutibilidade do EG e a correlação intra-sujeito entre área de condensação e percepção subjetiva de permeabilidade nasal. MÉTODOS: Estudo prospectivo onde 25 sujeitos foram avaliados com o EG por cinco minutos consecutivos; cada meia hora por quatro horas; cada dia no início da tarde, por cinco dias e toda a quinta-feira por cinco semanas consecutivas. Utilizou-se uma escala analógica visual para avaliar a percepção de respiração nos períodos. RESULTADOS: O coeficiente de correlação total (área direita mais esquerda) encontrado entre área de condensação e percepção subjetiva foi de r=0,04 (p=0,37). No lado esquerdo foi de r=0,08 (p=0,09) e no lado direito de r=0,05 (p=0,28). Os coeficientes de variação unilaterais medianos foram menores que 15% e os totais menores que 12%, independente do intervalo de tempo entre teste e re-teste. CONCLUSÃO: Não se evidenciou correlação significativa entre a percepção subjetiva e a área de condensação. A variabilidade unilateral foi maior do que quando considerados os valores totais (direito mais esquerdo) e não houve diferença na variabilidade das medidas de área de condensação nasal nos diferentes momentos do tempo.

Objective monitoring of nasal patency and nasal physiology in rhinitis

Nasal obstruction can be monitored objectively by measurement of nasal airflow, as evaluated by nasal peak flow, or as airways resistance/conductance as evaluated by rhinomanometry. Peak flow can be measured during inspiration or expiration. Of these measurements, nasal inspiratory peak flow is the best validated technique for home monitoring in clinical trials. The equipment is portable, relatively inexpensive, and simple to use. One disadvantage, however, is that nasal inspiratory peak flow is influenced by lower airway as well as upper airway function. Rhinomanometry is a more sensitive technique that is specific for nasal measurements. The equipment, however, requires an operator, is more expensive, and is not portable. Thus, it is applicable only for clinic visit measures in clinical trials. Measurements require patient cooperation and coordination, and not all can achieve repeatable results. Thus, this objective measure is best suited to laboratory challenge studies involving smaller numbers of selected volunteers. A nonphysiological measure of nasal patency is acoustic rhinometry. This sonic echo technique measures internal nasal luminal volume and the minimum cross-sectional area. The derivation of these measures from the reflected sound waves requires complex mathematical transformation and makes several theoretical assumptions. Despite this, however, such measures correlate well with the nasal physiological measures, and the nasal volume measures have been shown to relate well to results obtained by imaging techniques such as computed tomography scanning or magnetic resonance imaging. Like rhinomanometry, acoustic rhinometry is not suitable for home monitoring and can be applied only to clinic visit measures or for laboratory nasal challenge monitoring. It has advantages in being easy to use, in requiring little patient cooperation, and in providing repeatable results. In addition to nasal obstruction, allergic rhinitis is recognized to be associated with impaired mucociliary clearance and altered nasal responsiveness. Measures exist for the monitoring of these aspects of nasal dysfunction. Although measures of mucociliary clearance are simple to perform, they have a poor record of reproducibility. Their incorporation into clinical trials is thus questionable, although positive outcomes from therapeutic intervention have been reported. Measures of nasal responsiveness are at present largely confined to research studies investigating disease mechanisms in allergic and nonallergic rhinitis. The techniques are insufficiently standardized to be applied to multicenter clinical trials but could be used in limited-center studies to gain insight into the regulatory effects of different therapeutic modalities.

Reconstruction of dorsal and/or caudal nasal septum deformities with septal battens or by septal replacement: an overview and comparison of techniques

OBJECTIVES

The objectives of this study were to describe and compare two techniques used to correct nasal septum deviations located in the dorsal and/or caudal septum.

STUDY DESIGN

The authors conducted a retrospective clinical chart review.

METHODS

The authors conducted a comparison of functional and technical results between surgery in the L-strut of the septum in 114 patients with septal battens or by septal replacement by subjective self-evaluation and by examination of the position of the septum during follow up.

RESULTS

There was subjective improvement in nasal breathing in 86% of the septal batten group and in 94% of the septal replacement group. This difference was not statistically significant. The technical result was judged by examining the position of the septum during follow up as midline, slightly deviated, or severely deviated. The septum was significantly more often located in the midline during follow up in the septal replacement group than in the septal batten group.

CONCLUSION

Treatment of deformities located in the structurally important L-strut of the septum may be technically challenging and many functional, structural, and esthetic considerations must be taken into account. On the basis of this series, both septal battens and septal replacement techniques may be considered for correction of deviations in this area. The functional improvement rates were not significantly different between the techniques, although during follow up, the septum appeared to be significantly more often located in the midline in the septal replacement group. The techniques are described and their respective advantages and potential drawbacks are discussed.

Noninvasive system for evaluating allergen-induced nasal hypersensitivity in murine allergic rhinitis

Until now there has been no method for physiologically evaluating nasal hypersensitivity in mice. Enhanced pause (Penh) has been used as an indicator that reflects changes in the lower airway. Recently, however, there is disagreement regarding the significance of the Penh system; this is because Penh is not essentially a physiological parameter, and it might not necessarily represent a change in the lower respiratory tract. The purpose of the present study is to investigate whether Penh could be applicable for analyzing nasal hypersensitivity in mice. BALB/c mice were sensitized with ovalbumin (OVA) through a combination of intraperitoneal injection and daily intranasal challenge in an awake condition. Penh was measured at each time point during sensitization, or a serial change in Penh value was followed after the final nasal challenge and the effect of treatment was assessed. Following sensitization and nasal challenge, the Penh value gradually increased and showed a significant difference on day 14. Changes in IgE, eosinophil infiltration into nasal mucosa, and OVA-induced symptoms all strongly correlated with the increase in Penh. On day 19, after OVA nasal provocation, Penh gradually increased and reached maximal values 25 min after the challenge. Pretreatment with dexamethasone or a histamine H1 blocker significantly suppressed this increase in Penh. We confirmed that intranasal OVA challenge did not induce bronchoconstriction by measuring airway resistance and bronchoalveolar lavage fluid, and through histological examination. These results clearly demonstrate that Penh could be a useful noninvasive indicator for studying nasal hypersensitivity.

Changes in nasorespiratory function in association with maxillary distraction osteogenesis in subjects with cleft lip and palate

OBJECTIVE

The current study aimed to determine how nasorespiratory function changes in association with maxillary distraction osteogenesis (DO). Furthermore, with regard to impaired nasorespiratory function, the possibility of a relationship between the cleft side and laterality and any effect of maxillary distraction osteogenesis was investigated.

DESIGN

In this descriptive, prospective clinical report, subjective and objective data regarding nasorespiratory function before and after maxillary distraction osteogenesis were compared.

SUBJECTS

Data from 13 subjects with cleft lip and palate were used. Subjects had a severe maxillary deficiency and underwent distraction osteogenesis using a rigid external device system.

OUTCOME MEASURES

The subjective measure was the score on a questionnaire regarding nasorespiratory function using a visual analog scale. The objective measure was nasal resistance.

RESULTS

The visual analog scale score for two items significantly decreased just after distraction osteogenesis. Nasal resistance also significantly decreased 1 year after distraction osteogenesis. Moreover, nasal resistance on the cleft side was significantly greater than that on the noncleft side just before and 1 year after distraction osteogenesis. There was a significant positive correlation between changes in the visual analog scale score and nasal resistance.

CONCLUSIONS

These results suggest that nasorespiratory function changes in association with maxillary distraction osteogenesis in subjects with cleft lip and palate. Moreover, it appears that nasal obstruction on the cleft side does not change in subjects with unilateral cleft lip and palate.

Paradoxical sensation of nasal airflow in patients with common cold. Are we measuring the correct modality?

CONCLUSIONS

A paradoxical relationship between objective and subjective measures of nasal obstruction exists in participants not exposed to any treatment. The sensation of nasal obstruction may be due to the amalgamation of many different nasal sensations. Improved methods for measuring nasal sensations are required to further investigate the relationship between objective and subjective measures of nasal obstruction.

OBJECTIVES

In a recent study it was shown that the subjective sensation of nasal patency increased as the nasal passages became objectively more obstructed in patients who received a placebo compared to those who received an oral decongestant. This paradoxical response may be explained as a placebo effect, i.e. patients who received a placebo may have expected to feel less obstructed. The aim of the present study was to investigate this interesting paradox by determining objective and subjective measures of nasal obstruction over time in participants not exposed to any treatment.

MATERIAL AND METHODS

A total of 60 healthy participants with common cold were recruited. Objective and subjective measures of nasal obstruction were recorded at baseline and at 1 and 2 h using posterior rhinomanometry and a visual analogue scale.

RESULTS

Objective measures demonstrated an increase in nasal obstruction over time for both nasal passages considered together and for individual nasal passages. Subjective measures demonstrated a sensation of decreased nasal obstruction over time for both nasal passages considered together and for individual nasal passages.

Evidence for correlation of objective and subjective measures of nasal airflow in patients with common cold

OBJECTIVES

To utilize posterior rhinomanometry and conductance, as units of measurement, to further investigate the relationship between subjective and objective measures of nasal airflow.

DESIGN

A prospective, observational study.

SETTING

Common Cold Research Centre.

PARTICIPANTS

Sixty healthy volunteers from the staff and student population of Cardiff University with an upper respiratory tract infection.

MAIN OUTCOMES MEASURES

To determine correlations between visual analogue scores (VAS) and posterior rhinomanometry for total, unilateral, high and low conductance groups.

RESULTS

No correlation was found between total VAS and total conductance (r = 0.17, P = 0.10). A substantially significant correlation was found between unilateral VAS and unilateral conductance (rho = 0.50, P < 0.001). The unilateral VAS and conductance were highly correlated for the low total conductance group (rho = 0.61, P < 0.001).

CONCLUSIONS

Posterior rhinomanometry allows actual measurement of the combined and unilateral conductance of nasal passages. The units of conductance, as opposed to resistance, allow totally obstructed nasal passages to be included in analysis. Visual analogue scores and conductance correlate strongly in unilateral measures for participants with a low total nasal conductance. Posterior rhinomanometry and units of conductance are recommended for future studies investigating the relationship between objective and subjective measures of nasal airflow.

Repeatability of peak nasal inspiratory flow measurements and utility for assessing the severity of rhinitis

BACKGROUND

The measurement of peak nasal inspiratory flow (PNIF) provides a simple, cheap, fast and readily available tool for determining the extent of nasal airway patency. However, there are questions regarding its repeatability when used to assess the degree of nasal obstruction in large populations. Therefore, this study aimed to evaluate the repeatability of PNIF measurements and to assess their association with the signs and symptoms of rhinitis.

METHODS

The PNIF, rhinitis symptoms, judged by Meltzer questionnaire and rhinitis signs, as determined by anterior rhinoscopy, were assessed in 283 adults representative of the general population. One training and two test PNIF measurements were recorded during the same session.

RESULTS

The PNIF was highly reproducible (ICC = 0.92; 95% limits of agreement: +/-36 l/min). The PNIF was strongly correlated with rhinitis signs, measured by anterior rhinoscopy (rs= -0.38, P < 0.0001) but was not correlated with rhinitis symptoms, measured by questionnaire (rs= -0.11, P = 0.057). Differences in PNIF for subjects categorized as asymptomatic, mild or moderate/severe on the basis of rhinitis signs, were highly significant (P < 0.0001), but less significant on the basis of rhinitis symptoms (P = 0.04). A PNIF cut-off of 115 l/min had moderately high specificity (72%) and sensitivity (65%) and a high negative predictive value (90%) for moderate/severe signs of rhinitis.

CONCLUSION

In a large general population-based sample of young adults, PNIF was highly reproducible and closely related to the signs of rhinitis, as determined by clinical examination. The PNIF provides information that is qualitatively different to that provided by symptom scores and may be useful to measure the extent of nasal obstruction.

Effects of buffered saline solution on nasal mucociliary clearance and nasal airway patency

OBJECTIVE

To compare the effects of buffered hypertonic and buffered normal saline nasal spray on mucociliary clearance and nasal airway patency.

STUDY DESIGN AND SETTING

Double-blind trial with subjects acting as their own controls. Tertiary care academic medical center.

RESULTS

Buffered hypertonic saline and buffered normal saline both improved saccharine clearance times ( P < 0.0001 for buffered hypertonic and P = 0.002 for buffered normal saline). Buffered hypertonic saline improved saccharine clearance times more than buffered normal saline (39.6% vs 24.1%, P = 0.007). Neither buffered hypertonic nor buffered normal saline significantly affected nasal airway patency.

CONCLUSIONS

Both buffered hypertonic and buffered normal saline nasal spray significantly improved saccharine clearance times without affecting nasal airway patency. Buffered hypertonic saline affected saccharine clearance times to a greater degree than buffered normal saline.

CLINICAL SIGNIFICANCE

Buffered hypertonic and buffered normal saline sprays both improve mucociliary clearance and should therefore be beneficial in conditions such as rhinitis and sinusitis, which are associated with disruption of mucociliary clearance. However, these sprays do not appear to affect the nasal airway. Patients may therefore benefit from other treatments for "nasal congestion."

EBM RATING

B-2.

Use of interrupter technique in assessment of bronchial responsiveness in normal subjects

Background

A number of subjects, especially the very young and the elderly, are unable to cooperate and to perform forced expiratory manoeuvres in the evaluation of bronchial hyperresponsiveness (BHR). The objective of our study was to investigate the use of the interrupter technique as a method to measure the response to provocation and to compare it with the conventional PD₂₀ FEV₁.

Methods

We studied 170 normal subjects, 100 male and 70 female (mean ± SD age, 38 ± 8.5 and 35 ± 7.5 years, respectively), non-smoking from healthy families. These subjects had no respiratory symptoms, rhinitis or atopic history. A dosimetric cumulative inhalation of methacholine was used and the response was measured by the dose which increases baseline end interruption resistance by 100% (PD₁₀₀Rint, EI) as well as by percent dose response ratio (DRR).

Results

BHR at a cut-off level of 0.8 mg methacholine exhibited 31 (18%) of the subjects (specificity 81.2%), 21 male and 10 female, while 3% showed a response in the asthmatic range. The method was reproducible and showed good correlation with PD₂₀FEV₁ (r = 0.76, p < 0.005), with relatively narrow limits of agreement at -1.39 μmol and 1.27 μmol methacholine, respectively, but the interrupter methodology proved more sensitive than FEV₁ in terms of reactivity (DRR).

Conclusions

Interrupter methodology is clinically useful and may be used to evaluate bronchial responsiveness in normal subjects and in situations when forced expirations cannot be performed.

Endonasal spreader graft placement as treatment for internal nasal valve insufficiency: no need to divide the upper lateral cartilages from the septum

OBJECTIVE

To describe and evaluate results of a surgical procedure to treat internal nasal valve insufficiency with the use of spreader grafts placed via an endonasal approach without division of the upper lateral cartilages from the nasal septum.

DESIGN

Eighty-nine patients with complaints of nasal obstruction, at least partially due to internal nasal valve insufficiency, underwent this operation on 120 sides in a private practice setting. Only autologous material was used, and 3 different techniques for fixating the grafts were evaluated. All patients were prospectively studied, and subjective self-assessment was used to quantify the result of the operation.

RESULTS

On 53 sides (44%) nasal breathing was described as "optimal," and on 53 sides (44%) the result was deemed "improved." On 13 sides (11%) no change was noted, and on 1 side (1%) the postoperative situation was judged to be worse.

CONCLUSIONS

When opting for spreader grafts to treat internal nasal valve insufficiency, one does not necessarily need to perform an external approach, nor is separation of the upper lateral cartilages from the septum required. The endonasal technique presented herein is less invasive and can be used in conjunction with other procedures aimed at improving nasal patency.

The association of subjective nasal patency with peak inspiratory nasal flow in a large healthy population

This study, performed on 303 healthy volunteers, tested the null hypothesis that normal subjects were unable to assess their nasal patency when compared with objective measurement using peak inspiratory nasal flow rate (PINFR). Subjective assessments were made on a categorical scale and PINFR was measured using an In-Check meter. Analysis of variance showed that the peak inspiratory nasal flow rate, when grouped by the subjective scores, was significantly different.

Nasal congestion and airway obstruction: the validity of available objective and subjective measures

Rhinomanometry and acoustic rhinometry provide the best methods for objective assessment of nasal obstruction. Advanced equipment for these methods is now available, and most devices are reliable provided that care is taken to calibrate the device properly and, for rhinomanometers, the user is completely familiar with the mathematical algorithm for resistance used by the accompanying software. Suggestions for improvement in standardization of rhinomanometry are given. Rhinomanometry and rhinometry are both capable of objectively measuring nasal obstruction, but they are complementary methods that assess different nasal attributes, the former being a test of nasal function, and the latter a representation of nasal geometry. Objective methods are strongly recommended for use in the evaluation of pharmacologic agents that are expected to improve nasal airflow. When further studies needed to validate their use for long-term comparisons are done, these methods should find an increasing place in clinical practice.

Accuracy of nasal cannula pressure recordings for assessment of ventilation during sleep

Nasal prong pressure monitoring (PNOSE) is utilized to assess ventilation during sleep. However, it has not been rigorously validated against the gold standard of face-mask pneumotachography (VFM). Therefore, we compared PNOSE with VFM in 20 patients with suspected sleep apnea during nocturnal polysomnography, and analyzed factors affecting accuracy of PNOSE-derived variables. Patients rated their nasal obstruction on a visual analog scale. Mean +/- SE apnea/hypopnea index (AHI) by VFM was 24.0 +/- 5.1 h(-1). The bias (mean difference) and limits of agreement (+/- 2 SD) of AHI derived from PNOSE, and square root-transformed PNOSE, a measure proposed as a surrogate of airflow, were +3.9 (+/- 4.6), and -0.9 (+/- 9.0) h(-1). Subjective scores of nasal obstruction before polysomnographies did not herald inaccuracy of AHI from PNOSE. Square root-transformed PNOSE closely tracked pneumotachographic airflow over 10 breaths (r(2) among signals 0.88 to 0.96) but the relationship among these signals was highly variable if comparisons were extended over an entire night. Compared with face-mask pneumotachography, nasal pressure monitoring provides accurate AHI for clinical purposes even in patients perceiving nasal obstruction. Square-root transformation provides near linear nasal pressure/airflow relationships over a short time but is not essential for estimation of AHI.