Diagnosing nasal obstruction and its common causes using the nasal acoustic device: A pilot study

Objectives

There is a need to develop a medical device which can accurately measure normal and abnormal nasal breathing which the patient can better understand in addition to being able to diagnose the cause for their nasal obstruction.

The aim is to evaluate the accuracy of the nasal acoustic device (NAD) in diagnosing the common causes for nasal obstruction and diagnosing normal and abnormal (nasal obstruction) nasal breathing.

Methods

This pilot study recruited 27 patients with allergic rhinitis (AR), chronic rhinosinusitis (CRS), and a deviated nasal septum (DNS) which represents the common causes for NO and 26 controls (with normal nasal breathing). Nasal breathing sounds were recorded by the NAD akin to two small stethoscopes placed over the left and right nasal ala. The novel outcome metrics for the NAD include inspiratory nasal acoustic score (INA) score, expiratory nasal acoustic (ENA) score and the inspiratory nasal obstruction balance index (NOBI). The change in acoustic score following decongestant is key in this diagnostic process.

Results

Pre‐decongestant ENA score was used to detect the presence of nasal obstruction in patients compared to controls, with a sensitivity of 0.81 (95% CI: 0.66‐0.96) and a specificity of 0.77 (0.54‐1.00). Post‐decongestant percentage change in INA score was used to identify the presence of AR or CRS, with a sensitivity of 0.87 (0.69‐1.00) and specificity of 0.72 (0.55‐0.89) for AR; and a sensitivity of 0.92 (0.75‐1.00) and specificity of 0.69 (0.52‐0.86) for CRS. Post‐decongestant inspiratory NOBI was used to identify DNS, with a sensitivity of 0.77 (0.59‐0.95) and specificity of 0.94 (0.82‐1.00).

Conclusion

We have demonstrated that the NAD can help distinguish between normal and abnormal nasal breathing and help diagnose AR, CRS, and DNS. Such a device has not been invented and could revolutionize COVID‐19 recovery telemedicine.

Level of Evidence

Diagnostic accuracy study—Level III.

Reversible obstruction of the olfactory cleft: impact on olfactory perception and nasal patency

BACKGROUND

Temporary disruption of sensory input can be studied relatively easily for vision or hearing by covering the eyes or ears. In contrast, closing the nostrils affects not only the sense of smell, but also the ability to breathe through the nose and humidify and warm inhaled air. We hypothesized that filling the olfactory cleft (OC) with dissolvable nasal dressing (foam) would temporarily block olfaction while respecting nasal airflow.

METHODS

In 30 healthy volunteers, the OC was unilaterally obstructed in a back-to-front fashion. Orthonasal and retronasal olfactory function were tested before and after foam application. Ratings of odors and subjective nasal patency (SNP) were collected. Peak nasal inspiratory flow (PNIF) was used to measure nasal patency.

RESULTS

Foam was safely applied in every case using minimal instruments. No complications were reported. Orthonasal and retronasal test results decreased significantly in overall participants (all p < 0.0008). Indicating temporary anosmia, 3 subjects reached the lowest possible score for odor-threshold testing, with corresponding drops in retronasal test scores. PNIF values before and after foam application were not significantly different (p = 0.11). SNP ratings decreased slightly, but not significantly (p = 0.052). Odor-intensity ratings dropped significantly (all p < 0.05).

CONCLUSION

The OC can be safely obstructed with dissolvable nasal dressing, resulting in a decrease in odor-intensity and orthonasal and retronasal olfactory function test scores. This procedure may serve as a hyposmia model that maintains normal nasal airflow.

Nasal Peak Inspiratory Flow in Healthy and Obstructed Patients: Systematic Review and Meta-Analysis

OBJECTIVES

Nasal peak inspiratory flow (NPIF) is a practical and affordable tool that measures maximum inspiratory flow rate through both nostrils. Although NPIF values for healthy controls and patients appear to differ considerably, a generally expected value for populations with and without nasal obstruction has yet to be established. The aim of this systematic review and meta-analysis was to determine the mean NPIF value in populations with and without nasal obstruction.

METHODS

Medline (1946-) and Embase (1947-) were searched until July 1, 2017. A search strategy was used to identify studies that reported NPIF values for defined healthy or disease states. All studies providing original data were included. The study population was defined as having either normal nasal breathing or nasal obstruction. A meta-analysis of the mean data was presented in forest plots, and data were presented as mean (95% confidence interval [CI]).

RESULTS

The search yielded 1,526 studies, of which 29 were included. The included studies involved 1,634 subjects with normal nasal breathing and 817 subjects with nasal obstruction. The mean NPIF value for populations with normal nasal breathing was 138.4 (95% CI: 127.9-148.8) L/min. The mean value for populations with nasal obstruction was 97.5 (95% CI: 86.1-108.8) L/min.

CONCLUSIONS

Current evidence confirms a difference between mean NPIF values of populations with and without nasal obstruction. The mean value of subjects with no nasal obstruction is 138.4 L/min, and the mean value of nasally obstructed populations is 97.5 L/min. Prospective studies adopting a standardized procedure are required to further assess normative NPIF values. Laryngoscope, 131:260-267, 2021.

Total and Unilateral Peak Nasal Inspiratory Flow and Unilateral Visual Analogue Scale: Rationale in Indication and Outcomes of Septoplasty?

Septoplasty is one of the most frequently performed procedures in otorhinolaryngology. Proper selection of patients for septoplasty as well as examination is essential for good outcome of surgery. The aim of this study was to evaluate the suitability of combination of 2 simple, cheap, and easily performed examinations for indication and outcomes of septoplasty to evaluate the effectiveness in this type of surgery. Seventy patients were enrolled from 2 tertiary centers from the period of April 2017 to March 2018, who all underwent septoplasty for nasal septal deviation. Total and unilateral peak nasal inspiratory flow (PNIF), unilateral visual analogue scale, and nasal endoscopy for indication and outcomes of septoplasty were performed. Furthermore, assessment of possible correlation between subjective and objective data before and 3 months after septoplasty was done. Statistical analysis was carried out on the obtained data. Postoperatively the total and both unilateral PNIF measurements increased significantly compared with corresponding preoperative values and similarly means of visual analogue scale scores on both sides decreased 3 months after the procedure. No significant correlation was seen between objective and subjective outcomes neither before the surgery, nor postoperatively. The study confirmed the suitability of using PNIF as a simple and inexpensive tool that can be a reasonable alternative to rhinomanometry and which is able to reflect changes after septoplasty. Simultaneously, along with the expected improvement in the total PNIF and unilateral PNIF on deviated side, a slight but significant improvement in PNIF values on the nondeviated side was also demonstrated.

Relationship Between Nasal Cycle, Nasal Symptoms and Nasal Cytology

Background

The nasal cycle is the spontaneous congestion and decongestion of nasal mucosa that happens during the day. Classically, 4 types of nasal cycle patterns have been described: (1) classic, (2) parallel, (3) irregular, and (4) acyclic. Hypothalamus has been considered as the central regulator even if several external factors may influence its activity.

Objective

The aim of the study was to evaluate the presence of a correlation between nasal cycle pattern, nasal cytology and nasal symptoms.

Methods

Thirty healthy volunteers have been enrolled in the study. All subjects completed a Sino-Nasal Outcome Test-22 questionnaire and a Visual Analog Scale (VAS) for nasal obstruction. The nasal cycle was studied by means of peak nasal inspiratory flow. Nasal cytology has been used to evaluate the presence of local nasal inflammation.

Results

Nineteen subjects showed a parallel nasal cycle pattern, while 11 showed a regular one. A parallel pattern was present in 60% of asymptomatic subjects and in 67% of the symptomatic one ( P = 1). VAS for nasal obstruction did not show a significant difference between the 2 patterns of the nasal cycle ( P = .398). Seventeen subjects had a normal rhinocytogram, while 13 volunteers showed a neutrophilic rhinitis; 53.8% of the subjects with a neutrophilic rhinitis showed a parallel pattern, while the remaining 46.2% had a regular one. In the case of a normal cytology, 70.6% of the volunteers had a parallel pattern and 29.4% had a regular one. Differences between the 2 groups were not statistically significant ( P = .575).

Conclusion

Rhinitis with neutrophils seems to not influence the nasal cycle pattern. Based on the present results, the pattern of nasal cycle does not influence subjective nasal obstruction sensation.

Nasal function before and after rapid maxillary expansion in children: A randomized, prospective, controlled study

OBJECTIVES

Children can well detect and respond to odours in order to have information about food and environment. Rapid Maxillary Expansion seems to improve dental and skeletal crossbite and increase nasal patency correcting oral respiration in children. A previous pilot study suggested that Rapid Maxillary Expansion may lead to improved N-Butanol olfactory thresholds, and peak nasal inspiratory flow values (PNIF). The aim of the present study was to prospectively evaluate olfactory threshold, nasal flows and nasal resistances in children aged from 6 to 11 years before and after Rapid Maxillary Expansion, comparing treated children with a control group of similar age, growth stage (prepubertal) and transversal skeletal deficiency.

METHODS

N-butanol olfactory thresholds, anterior active rhinomanometry (AAR) and PNIF were measured in 11 children (6-11 years) before (T0), immediately and 6 months after Rapid Maxillary Expansion application (T1 and T2 respectively), and in a control group of 11 children (6-11 years) whose members remained under observation for the period of the study.

RESULTS

Considering the study group, PNIF values improved at T1 respect to the T0 values (p = 0.003), while T2 values were significantly higher than T0 ones (p = 0.0002). N-Butanol Olfactory Threshold significantly improved at each control (p = 0.01, p = 0,01 and p = 0.0003, for T1 vs T0, T2 vs T1, T2 vs T0 respectively). No differences on AAR values were found during the six months follow-up in this group. Considering the control group, no significant differences were found for any of the considered variables during the time of the study. Comparing the two groups, there was a significant increase of PNIF values in the study group compared to the control group (p = 0.003) at T1, which was even more evident six months after Rapid Maxillary Expansion (p = 0.0005). This improvement was not shown by AAR values. N-Butanol Olfactory Threshold showed a significant improvement at T2 respect to T1 (p = 0.002) and T0 (p = 0.0005).

CONCLUSION

Rapid Maxillary Expansion seems to significantly improve the respiratory capacity of treated patients, at least in terms of PNIF, and their olfactory function, measured by N-Butanol Olfactory Threshold Test. Further studies should be performed to evaluate if also changes in nasal resistances, measured by AAR, could occur, maybe considering a larger group of subjects and possibly using 4-phase rhinomanometry in order to evaluate the effective resistances during the entire breath.

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.

Nasal patency and craniocervical posture in scholar children

ABSTRACT Changes in head posture have been observed as a compensatory mechanism for the nasal airflow impairment. This study aimed to compare the craniocervical posture between children with normal and decreased nasal patency and correlate nasal patency with craniocervical posture. Children aging from six to twelve years went through nasal patency and craniocervical assessments. The biophotogrammetric measures of craniocervical posture used were Cervical Distance (CD), Head Horizontal Alignment (HHA) and Flexion-Extension Head Position (FE), evaluated by SAPO software (v.0.68). Nasal patency was measured using Peak Nasal Inspiratory Flow meter (PNIF) and Nasal Obstruction Symptom Evaluation (NOSE) scale. One hundred thirty-three children were distributed into two groups: G1 (normal nasal patency - PNIF higher than 80% of predicted value) with 90 children; G2 (decreased nasal patency - PNIF lower than 80% of predicted value) with 43 children. Differences between groups were not found in CD and HHA measures. FE was significantly higher in G2 than G1 (p=0.023). Negative weak correlation between FE and %PNIF (r=-0.266; p=0.002) and positive weak correlation between CD and PNIF (r=0.209; p=0.016) were found. NOSE scores negatively correlated with PNIF (r=-0.179; p=0.039). Children with decreased nasal patency presented greater head extension. This postural deviation is prone to increase as nasal airflow decreases, thus indicating the relationship between craniocervical posture and nasal patency. Lower values of PNIF reflected on additional problems caused by nasal obstruction symptoms.

The need for an objective measure in septorhinoplasty surgery: are we any closer to finding an answer?

OBJECTIVES

To assess the reliability of nasal inspiratory peak flow (NIPF) in providing a clinically accurate objective measure following functional septorhinoplasty by comparing it to the validated disease-specific quality-of-life questionnaire, SNOT-22. Studies so far have demonstrated poor correlation between bilateral NIPF and symptom-specific nasal questionnaires following septorhinoplasty.

DESIGN

To perform a prospective comparative analysis between NIPF and the validated disease-specific quality-of-life questionnaire SNOT-22 and to determine whether a correlation exists following septorhinoplasty surgery.

SETTING

The Royal National Throat Nose and Ear Hospital, London.

PARTICIPANTS

A total of 122 patients (78 males, 44 females; mean age 33.5 ± 12.2 years) were recruited from the senior authors rhinology clinic and underwent functional septorhinoplasty surgery.

MAIN OUTCOME MEASURES

Preoperative and postoperative nasal inspiratory peak flow (NIPF) measurements were performed in addition to the completion of three subjective quality-of-life and symptom assessment tool questionnaires; Sinonasal Outcome Test 22 (SNOT-22), Nasal Obstruction Symptom Evaluation (NOSE) and Visual Analogue Scale (VAS: 0-10).

RESULTS

The mean preoperative NIPF was 88.2 L/min, and the postoperative value was 101.6 L/min and showed a significant improvement following surgery (P = 0.0064). The mean total SNOT-22 score improved significantly from 48.6 to 26.6 (P < 0.0001); the NOSE score from 14.1 to 6.6 (P < 0.0001); and the Visual Analogue Scale (VAS) blockage score from 6.9 to 3.2 (P < 0.0001). All individual domains assessed showed improvements postoperatively, but no correlation was found between the NIPF and SNOT-22 score. Equally, we did not find a correlation between NIPF and the symptom-specific NOSE questionnaire and the nasal blockage domain on the Visual Analogue Scale (VAS) scale.

CONCLUSION

We have demonstrated that NIPF does not correlate with the SNOT-22 disease-specific questionnaire, although both outcomes significantly improve postoperatively. At present, we are still lacking a clinically accurate objective measure of nasal function for the evaluation of patients undergoing septorhinoplasty surgery.

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.

N-butanol olfactory threshold and nasal patency before and after palatal expansion in children. A preliminary study

OBJECTIVES

Olfaction is based on the function of the nasal olfactory receptors. Children can well detect and respond to odors in order to have information about food and environment. Rapid maxillary expansion seems to improve dental class and increase nasal patency correcting oral respiration in children. Nevertheless, there are no studies demonstrating that expansion in pediatric patients could influence olfactory sensitivity. The aim of this study was to evaluate olfactory threshold and nasal patency in children aged from 6 to 12 years before and after rapid maxillary expansion.

METHOD

N-butanol olfactory thresholds, anterior active rhinomanometry, and peak nasal inspiratory flow were measured in 12 children (6-12 years) before (T0), 20 days (T1), and 6 months after rapid maxillary expansion application (T2).

RESULTS

A significant lower olfactory threshold was found comparing T2 and T0 N-butanol olfactory threshold values (p=0.038). Peak nasal inspiratory flow showed a significant improvement both at T1 and T2, with respect to T0 values (p=0.043 and p=0.0001, respectively). T2 nasal resistances showed a trend towards a significant reduction when compared with T1 values (p=0.15).

CONCLUSION

This pilot study suggested that rapid maxillary expansion may lead to improved N-butanol olfactory thresholds, at least 6 months after palatal expansion. Furthermore, rapid maxillary expansion seems to improve peak nasal inspiratory flow values, and finally although with lower sensitivity, reduce nasal resistances as measured by rhinomanometry.

Reliability and acceptability of measuring sniff nasal inspiratory pressure (SNIP) and peak inspiratory flow (PIF) to assess respiratory muscle strength in older adults: a preliminary study

BACKGROUND

Sniff nasal inspiratory pressure (SNIP) and peak oral inspiratory flow (PIF) are portable, relatively new methods for indirect measurement of respiratory muscle strength. The reliability and acceptability of these measures were investigated in older adults.

METHODS

The study included 21 self-reported healthy adults, aged 65-84 years (mean 73.5; SD 6.4 years). Participants were tested in a sitting position on two occasions, 1 week apart. The best of three attempts for PIF measured through the mouth, and five for each nostril for SNIP were recorded. Reliability was tested using intra-class correlation coefficient (ICC), standard error of measurement, minimal detectable change (MDC) and Bland and Altman analysis. Feedback on the measures in relation to ease of completion and preference was obtained using a semi-structured interview.

RESULTS

Between-day reliability of SNIP and PIF were ICC3,1 0.76 (95 % CI 0.49-0.9) and 0.92 (0.81-0.97), respectively. Standard error of measurement for SNIP (11.94 cmH2O) and MDC (33.10 cmH2O) were at the least 61 % higher than for PIF. The participants reported difficulties in performing SNIP, rating it as being less easy and uncomfortable to perform than PIF, with a higher rate of missing data for SNIP due to participants' dislike of the test.

CONCLUSIONS

The wide range of SNIP readings, lower ICC value and negative user feedback are suggestive of a less robust and unacceptable clinical measure. PIF showed excellent reliability and acceptability and is therefore recommended for assessing inspiratory muscle strength in older people without known obstructive lung disease.

Peak nasal inspiratory flow: a useful and handy tool for the diagnosis of nasal obstruction in the elderly

The global population is aging, with the over-65 age group expected to double in the USA by 2030. Three subcategories of elderly people have been identified: "young old" (from 65 to 74 years), "older old" (from 75 to 84) and "oldest old" (85 or more). Rhinosinusitis is a common disease that affects more than 31 million people in the USA every year. Nasal obstruction is one of the most common symptoms in patients affected by rhinosinusitis. An accurate nasal obstruction evaluation in the elderly is becoming of increasing interest for medical doctors, especially for geriatricians. Peak nasal inspiratory flow (PNIF) is a cheap and easy method for assessing nasal patency. The purpose of the study was to compare young old normal PNIF values with older old normal PNIF values. Charts relating PNIF normal values in the elderly with various explanatory variables have been provided. PNIF measurements were performed in 113 volunteers aged 65-84 years. One hundred and five of them fulfilled the study criteria and were self-reported healthy elderly. None of them complained of nasal symptoms. Data were statistically analyzed and figures and tables were produced relating PNIF to height, sex and age. PNIF values decreased with age (p = 0.0053) and were significantly lower in the "older old" sub-cohort than in the "young old" group (p = 0.007). Nasal obstruction in the elderly is a common problem and appropriate diagnosis and treatment are important for improving their quality of life. The measurement of PNIF could be useful in evaluating elderly patients who complain of nasal obstruction.