Volume 102 Number 3

March 1990

In the past, causes of increased nasal resistance have been primarily attributed to enlarged adenoid tissue, deviated nasal septum, nasal polyps, obstructive turbinates, and/or swollen nasal mucosa. Current studies reveal that the anterior nasal skeleton plays an equal or even more important role in determination of total resistance to airflow than do structures more posteriorly located in the nasorespiratory tract. 1

The anterior nasal passage is a frequent site of pathology causing nasal obstruction. The nasal valve and the surrounding area can be compromised by numerous anatomic and physiologic changes, including:

1. Anterior septal deviation

2. Common colds, hay fever, nasal allergy

3. Aggressive resection of cartilage during rhinoplasty

4. Scarring from burns, surgery or trauma

5. Bell's palsy and stroke

6. Senile atrophic changes of upper and lower cartilages.

Numerous medicinal modalities of treatment to reduce anterior nasal resistance have been tried with little success. Until recently, most products directed to relieve nasal obstruction and to reduce nasal resistance have been medications with systemic side effects, local irritations, and potential addiction. Although the anterior nasal skeleton is anatomically easily accessible, because of its esthetic prominence, surgical intervention may be an undesirable alternative, contraindicated, or declined by the patient.

In previous studies, nasal prostheses have subjectively alleviated nasal obstruction and have been objectively proved to decrease the nasal resistance. A device for mechanically dilating the nasal valve was described as early as 1905 in the British Medical Journal.2 In 1986, Lancer and Jones3 prescribed such a device for one of their patients and reported dramatic, subjective, nonsurgical relief of nasal obstruction. Improvement was also demonstrated objectively with active anterior rhinomanometry, showing significant reduction in nasal resistance. A therapeutic mechanical nasal dilator was described in Rhinology in 1985 by Ford and Rezakany.4 In this study, five patients were fitted with stents. Here again, objective rhinomanometry demonstrated decreases in nasal resistance and showed that surgery had been made unnecessary. The average nasal resistance was reduced to a pressure that has been shown to be below the threshold that triggers mouth breathing.5

Although promising, until now all previous nasal stents have been cumbersome, expensive to fabricate, awkward, and uncomfortable for the patient. We have now developed a Mechanical Therapeutic Nasal Dilator* that has shown dramatic subjective improved breathing and excellent patient acceptance.

The Breathe With Eez Mechanical Therapeutic Nasal Dilator is made of biocompatible 304 stainless steel alloy wire (Figs. 1 and 2). Formed as a looped spring, it is flexible, collapsible, and self-expanding. The device conforms to any size or shape of nasal vestibule. By gently exerting outward pressure in all directions, it dilates the nasal valve and deflects the nasal septum. The device is available in 3 sizes (small, medium, and large) and will comfortable fit most noses with little or no adjustment. It is easily inserted and removed by the patient. The design does not allow it to slip back into the nasal cavity, which precludes aspiration of the device.

A trial study was conducted at The Brookdale Hospital Medical Center using the Mechanical Therapeutic Nasal Dilator. In the fall of 1987, twenty patients with anterior nasal obstruction were introduced to the device. Of the twenty patients, four refused to try the prosthesis. One patient would not tolerate the prosthesis in the nose. The remaining fifteen patients were the subjects of our investigation. The subjects ranged in ages from 20 to 75 years. Of these, 8 were women and 7 were men. The total aggregate experience wearing the device was 120 patient months, ranging from a use of 3 to 24 months.

To date, we have had no complications of any kind. The manufacturer, Breathe With Eez Corporation, reports no significant complications from the several thousand devices that have been distributed over the past 3 years.

Current medical treatment for nasal obstruction have been mostly unsuccessful. Custom-made, rigid nasal stents have been expensive, awkward, and uncomfortable to use. Surgical intervention has been the primary approach for these problems. Often surgery may not be indicated because of poor surgical classification, time and expense, or patient preference. Surgical intervention may be unsuccessful. This new device is now available to treat nasal obstruction or to allow surgery to be postponed until a more favorable future time. Where surgery is indicated, this device will demonstrate the advantages of unobstructed nasal breathing to the patient.

A comprehensive investigation using rhinomanometry is currently underway at The Brookdale Hospital Medical Center, Brooklyn, New York.

In this preliminary study, the Mechanical Therapeutic Nasal Dilator has proved to be an excellent device to decrease anterior nasal obstruction. It is effective, safe, inexpensive, and easy to use.

We invite comment and additional research from our colleagues using the Breathe with Eez device.

1. Berkinshaw ER, Spalding PM, Vig PS. The effects of methodology on the determination of nasal resistance. Am J Orthod Dentofac Orthop 1987;92:329-35.
2. Francis A. Medical and surgical appliances: an alae nasi prop. Br Med J 1905;2:1461.
3. Lancer M, Jones AS. The Francis alae nasi prop and nasal resistance to airflow. J Laryngol Otol 1986;100:539-41.
4. Ford CN. Rezakany S. A nasal prosthesis for the treatment of nasal airway obstruction. Rhinology 1985;23:229-33.
5. Proffit WR. Contemporary orthodontics. St. Louis: CV Mosby Co, 1986:112

*The Mechanical Therapeutic Nasal Dilator is manufactured by The Breathe With Eez Corporation of Brooklyn, New York. The device is U.S. Patented #4759365. International patents are pending. It is U.S. FDA 510K market approved.

From the Division of Otolaryngology, Brookdale Hospital Medical Center, State University of New York (Dr. Chaudhry) and New York University College of Dentistry (Dr. Askinazy).

Presented at the Annual Meeting of the American Academy of Otolaryngology- Head and Neck Surgery, New Orleans, La., Sept. 24-28, 1989.

Submitted for publication Sept. 25, 1989; accepted Oct. 24, 1989.

Reprint requests: Frank Y. Askinazy, DDS, Clinical Associate Professor, New York University, 545 Central Ave, Cedarhurst, NY 11516.

23/4/17727

Volume 34, Number 1

March 1996

Rhinomanometric Evaluation of the improved mechanical therapeutic nasal dilator in patients with anterior nasal obstruction

M. Rashid Chaudhry, Sajjad Akhtar, Fergens Dwalsaint

Department of Otolaryngology, State University of New York, Health Science Center at Brooklyn, New York, USA

Nasal obstruction is a common and distressing symptom. It is not always amenable to medical therapies or surgical procedures. The immense magnitude of the problem is evident by an estimated US$ 5.6 billion spent annually in the United States alone on remedies to relieve it (Kimmelman, 1989). Resistance to the air flow occurs mainly in the nasal valve area. In this region, the nasal passages between the free edges of the inferior turbinate and nasal septum are quite narrow. The nasal valve, main regulator of the nasal airflow, is a part of the nasal valve area. It is a triangular slit-like opening between the causal ends of the upper lateral cartilage and septum (Kasperbauer and Kern, 1987). Nasal prostheses capable of increasing the cross-sectional area of the nasal valve have been reported in the medical literature as early as 1905 (Francis, 1905). Essentially, these devices have been used to support collapsed ala nasi in order to reduce nasal obstruction and improve cosmetic appearance (Lancer and Jones, 1986). There has been a renewed interest in mechanical nasal dilators following recent reports showing that mechanical dilation of the nasal airways during sleep can decrease both the frequency and severity of obstructed breathing events in patients with obstructed sleep apnea (Hoijer et al., 1992). Many of the external and internal mechanical nasal dilators have been shown to be affective both subjectively and objectively (Ford and Rezakany, 1985; Petruson, 1988). However, these have been expensive to fabricate, cumbersome to use and uncomfortable for the patient. We have developed an Improved Mechanical Therapeutic Nasal Dilator (IMTND) which has been shown to facilitate breathing subjectively, is easy to use, and has a good patient's acceptance (Chaudhry and Askinazy, 1990). In this study the effectiveness of this mechanical nasal dilator has been evaluated rhinomanometrically and compared to that of a local decongestant.

Thirty-eight patients with anterior nasal obstruction were entered into the study. Five patients could not tolerate the nasal dilator and were excluded from the study leaving 33 patients as the basis of this report. Twenty-eight patients had a deviated nasal septum, two patients had collapsed ala nasi, and the remaining three had other skeletal problems of the nose. There were 22 males and 11 females with a mean age of 26 years (range: 18-68 years).

We used the Improved Mechanical Therapeutic Nasal Dilator (IMTND). The IMTND is manufactured by the Breathe-With-EEZ Corporation of Brooklyn, New York. The device is US patented (#4759365), international patents are pending, and it is US FDA 510K market approved. It is made of biocompatible 304 stainless-steel alloy wire formed as a loop spring. This structure allows it to be flexible, collapsible and self-expanding. We used three available sizes of the device (small, medium, and large) which comfortably fitted all the patients with little or no adjustment.

The anterior rhinomanometric studies were done using Rhinotest MP 500. This equipment automatically calculates resistance from the pressure flow curve. Following the recommendations of the European International Meeting on the Standardization of Rhinomanometry, the values of flow and resistance were recorded at a pressure of 150 Pa (Clement, 1980). All the patients were examined by an otolaryngologist at a date prior to the test. It was made sure that patients had not taken any antihistamine and oral or nasal decongestant at least 24 h prior to the test. In each instance the patients were acclimated to standard room temperature (21+/- 2 C) and humidity (20%) for 15 min before the test. The patients were fully informed about the procedure during this time. In all the patients the test was performed in a systematic manner: (1) the unassisted baseline values for resistance were recorded; (2) the IMTND was inserted in each nostril and rhinomanometric studies performed for each nostril separately; and (3) to evaluate the effect of decongestion, 1% phenylephrine was sprayed into each nostril during inhalation. After 10 min, rhinomanometric tests were repeated for each nostril, first without IMTND and then with IMTND inserted into the nostrils.

The distribution of nasal resistance has been reported to be skewed towards higher values. Statistical analysis thus requires the use of non-parametric tests. We used the Wilcoxon signed-rank test for the analysis of resistance data. Accordingly, the values for resistance are presented as median (range).

The values obtained in the unassisted baseline state are shown in Table 1. A comparison of the IMTND assisted condition with the baseline unassisted conditions, showed a decrease in the median nasal resistance from 0.340 Pa/cm^3/s to 0.250 Pa/cm^3/s (p<0.001). Expressing these values as a percentage of the baseline resistance, the median decrease in nasal resistance was 26%. The median value of nasal airway resistance after decongestion decreased from 0.340 Pa/cm^3/s to 0.200 Pa/cm^3/s, representing a 41% decrease (p<0.001). After IMTND insertion in the decongested nostrils the nasal resistance decreased from 0.340 Pa/cm^3/s to 130 Pa/cm^3/s (p<0.001) Compared to the baseline values, the median decrease in nasal resistance was 62% (Figure 1).

Approximately half of the total respiratory tract resistance is attributed to the nasal air flow resistance (Kasperbauer and Kern, 1987). The mean total resistance in our patients with nasal obstruction was higher than the mean total values of 0.33 Pa/cm^3/s reported for healthy subjects (Shelton and Eiser, 1992). The higher values of nasal resistance for the left nostril may represent a majority of our patients with deviated nasal septum affecting the left nostril.

Resistance

total

Right nostril

Left nostril

Mean

0.376

0.677

1.244

SD

0.166

0.344

0.852

Median

0.340

0.570

0.445

Upper 95% c.i.*

0.317

0.555

0.942

Lower 95% c.i.*

0.435

0.799

0.320

The nasal valve area, which is the narrowest portion of the nasal passage, is the main site of resistance (Kimmelman, 1989). The resistance offered to the nasal air flow at the nasal valve depends mainly on skeletal and mucosal structures. It is to be noted that these two factors contribute to the nasal resistance separately. In order to find the nasal resistance, solely due to cartilaginous and bony structures, some authors recommend the use of vasoconstrictors to decrease the mucosal swelling (Linder-Aronson and Backstrom, 1960). Any structural deformity of the cartilaginous portion of the nasal skeleton or swelling of the mucosa can lead to nasal obstruction, particularly when the nasal valve is involved.

The preferred form of treatment for nasal obstruction of skeletal origin is surgical. In some patients alternate modes of therapy are desired due to some contra-indication to the surgery, patient's preference, or to achieve instant relief in mild obstruction. Surgical treatment for nasal obstruction has been reported to increase the nasal air flow by 33% (Gordon et al., 1989). Using a different type of nasal dilator a 24% increase in the air flow has been reported for healthy subjects (Petruson, 1988). To our knowledge the effectiveness of nasal dilators has not been compared with nasal decongestants before. However, in healthy subjects treatment with xylometazoline has been reported to increase the nasal air flow by 28% (Petruson, 1981). We achieved similar results using the IMTND and 1% phenylephrine separately in patients with nasal obstruction. The insertion of the IMTND in a decongested state resulted in a synergetic effect increasing the nasal air flow by 163%.

The IMTND increases the nasal valve area by exerting dilatory pressure internally in the nasal skeleton thus increasing the nasal angle, normally an action performed by the ala nasi. The decongestants increase this area by exerting their effect on the nasal mucosa especially on the anterior part of the inferior turbinate. As observed in this study both of these agents can significantly decrease the nasal resistance and increase the nasal airflow. An even higher decrease in the nasal resistance and increase in air flow was observed with a combination of IMTND with decongestant. This effect may have been produced by the simultaneous action of these agents on the two main contributors to the nasal resistance. A selected group of patients with nasal obstruction due to anterior nasal pathologies does not allow us to draw definitive conclusions. However, it may be speculated that the usefulness of the IMTND or nasal decongestant would depend on the aetiology of nasal obstruction. As in most of the patients there is a combination of structural and mucosal problems, the maximum benefit can be achieved by using the IMTND with a nasal decongestant. It may be concluded that the IMTND can significantly decrease the nasal resistance. A combination of the IMTND with nasal decongestant can further improve the results. Further studies are required to correlate the effectiveness of the IMTND and/or decongestant with the aetiology of the nasal obstruction.

1. Chaudhry MR, Askinazy FY (1990) Improved mechanical therapeutic nasal dilator to treat nasal airway obstruction. Otolaryngol Head Neck Surg 102: 298-300.
2. Clement PR (1980) Committee report on standardization of rhinomanometry. Rhinology 22: 151-155.
3. Ford CN, Rezakany S (1985) A nasal prosthesis for the treatment of nasal airway obstruction. Rhinology 23: 229-233.
4. Francis AQ (1905) Medical and surgical appliances; An alae nasi prop. Brit Med J 2: 1461.
5. Gordon ASD, McCaffrey TV, Kern EB, Pallanch JF (1989) Rhinomanometry for preoperative and postoperative assessment of nasal obstruction. Otolaryngol Head Neck Surg 101: 20-26.
6. Hoijer U, Ejnell H, Hedner J, Petruson B, Eng LB (1992) The effects of nasal dilation on snoring and obstructive sleep apnea. Arch Otolaryngol Head Neck Surg 118: 281-284.
7. Kasperbauer JL, Kern EB (1987) Nasal valve physiology. Otolaryngol Clin North Am 20: 699-719.
8. Kimmelman CP (1989) The problem of nasal obstruction. Otolaryngol Clin North Am 22: 253-264.
9. Lancer M, Jones AS (1986) The francis alae nasi prop and nasal resistance to air flow. J Laryngol Otol 100: 539-541.
10. Liner-Aronson S, Backstorm A (1960) A comparison between mouth and nose breathers with respect to occlusion and facial dimensions. Odontol Revy 11: 343-376.
11. Petruson B (1981) Treatment with xylometazoline (Otrivin) nose drops over a six weeks period. Rhinology 19: 167-172.
12. Petruson B (1988) Improvement of the nasal air flow by the nasal dilator Nozovent. Rhinology 26: 289-292.
13. Shelton DM, Eiser NM (1992) Evaluation of active anterior and posterior rhinomanometry in normal subjects. Clin Otolaryngol 17: 178-182.