Disclaimer: The information contained within the Grand Rounds Archive is intended for use by doctors and other health care professionals. These documents were prepared by resident physicians for presentation and discussion at a conference held at Baylor College of Medicine in Houston, Texas. No guarantees are made with respect to accuracy or timeliness of this material. This material should not be used as a basis for treatment decisions, and is not a substitute for professional consultation and/or peer-reviewed medical literature. Nasal Obstruction: The Nasal Valves In most regions of the human body, the famous edict of Mies van der Rohe holds true -- "form follows function." However, the reverse applies to rhinology: function is almost solely dependent on form. A troublesome and common complaint in the practice of Otolaryngology is that of nasal obstruction. We invest significant resources into the treatment of such complaints. In the United States alone, over 60 billion dollars a year is spent on the surgical treatment of this complaint. For many years, nasal obstruction has been equated with nasal septal deformity and, therefore, septal surgery. Nasal obstruction is a symptom, not a diagnosis, and there is a plethora of medical and structural conditions that can cause such symptoms. Surgical intervention can usually be of benefit when one or more of the four nasal valve areas are compromised. It is these four areas that are the focus of this presentation. The rhinological literature identifies four nasal valves or flow limiting segments: external valve, internal valve, septal valve, and inferior turbinates. Understanding normal nasal airflow is a complex task based on the laws of fluid dynamics. Flow means pressure divided by resistance. Flow within the nose is both laminar and turbulent. Each flow component is important in the perception of "normal" nasal function. Laminar flow provides movement of air toward the lower respiratory tract. Turbulent airflow causes eddied currents within the nostril. This allows for the distribution of the air column across a larger surface area for conditioning and for the air to reach the olfactory area. The air column can be affected by either a narrow or a very wide nasal passage. When the normal, turbulent air flow pattern is disturbed, it is perceived as nasal obstruction. This helps explain the few patients that complain of persistent nasal obstruction in the postoperative period even with a widely patent nasal passage. Examining each of the four valves, the first flow limiting segment is the paired external valves. Each of these valves is composed of the lower lateral cartilage, the columella, and the nasal floor. Active dilatation of this valve occurs with each inspiration by action of the nasalis muscles. Malfunctions in this area can be the result of trauma, facial nerve palsies or congenital anomalies of the alar cartilage. By far the most common cause of external valve malfunction is iatrogenic or surgically induced trauma. The paired internal valves consist of the caudal end of the upper lateral cartilage, the nasal septum, and the soft tissue surrounding the piriform aperture. This valve is located at the anterior end of the inferior turbinate. Unlike the external valve, the internal valve functions paradoxically. During inspiration this flow limiting segment narrows and accounts for over 50% of the normal nasal resistance. Again, nasal surgery, especially nasal tip surgery, is the most common cause of internal valve malfunction. The aging process can also adversely affect the internal valve function by decreasing tissue elasticity and causing further collapse. The nasal septal valve is composed of the perpendicular plate of the ethmoids posteriorly, the quadrangular cartilage anteriorly, and the vomer inferiorly. The maxillary crest and palatine bones complete the septal floor. The septum is uniquely constructed to absorb direct trauma. The quadrangular cartilage articulates directly with the bone posteriorly and inferiorly. Such direct cartilage-bone articulation is rare without intervening ligaments and it is this unique construction that allows more lateral mobility. Despite this mobility though, septal deviation is a very common problem. It is estimated that only 23% of the adult population has a straight septum. The anterior head of the inferior turbinate is used to define the degree of nasal obstruction due to septal deformities. Studies have shown that anterior deflections of the septum (those anterior to or at the head of the inferior turbinate) account for most of nasal symptoms associated with septal deformities. Smaller, anterior deflections are much more important in the perception of nasal airflow than larger posterior deformities. Through vascular congestion and decongestion, the inferior turbinates act as the fourth and final flow limiting segment. The inferior turbinates contain special erectile tissue consisting of venous sinusoids surrounded by smooth muscle. There is a normal nasal cycle in which this erectile tissue vasodilates and vasoconstricts. The cycle occurs approximately every four hours -- first one side then the other. Although the nasal cycle is a normal phenomenon, this pattern can sometimes be confused as obstructive symptoms. This is especially true in the early postoperative period after nasal surgery. The inferior turbinates will also expand to fill the space allotted on the floor of the nose. If there is a significant septal deviation then the inferior turbinate on the side opposite the septal deformity can become hypertrophic. Failure to recognize and address this compensatory hypertrophy during septoplasty can lead to persistent nasal obstruction in the postoperative period. Traditionally, clinicians have relied on the history and physical examination to evaluate anatomic abnormalities related to complaints of nasal obstruction. Objective measures, such as computerized tomography and rhinomanometry, do exist to document the degree of nasal obstruction. A newer technique developed by Hilberg and coworkers in 1989 is Acoustic Rhinometry. This uses ultrasound technology to provide a graphic representation of the cross-sectional area of the nasal passage. This technique requires no patient cooperation and results correlate well with clinical signs and symptoms of nasal obstruction as well as the anatomic site of the obstruction. Although acoustic rhinometry is used today as a research tool, it can be used for preoperative and postoperative documentation, as well, as a means to monitor both medical and surgical treatment regimens. The treatment of nasal obstruction involving the valve areas begins with proper diagnosis. Often more than one area is involved. External valve problems are best treated with augmentation procedures. Using methods popularized by Sheen, bone or cartilage can be used as grafting material to strengthen the alar cartilage. Resection of the medial crural plate can also provide further widening of the external valve if necessary. Treatment of internal valve problems usually involves one of three methods: scar revision, medial osteotomies, or on-lay grafting of the nasal dorsum. The classic septal surgery, or submucous resection, involves removal of all obstructing bone and cartilage while preserving adequate caudal and dorsal margins of the quadrangular cartilage to prevent saddle nose deformity. Today, a more conservative approach referred to as septoplasty has become popular. After the deviated cartilage and bone have been removed it is morselized and then reinserted. Neither technique, however, guarantees relief of obstructive symptoms. The literature suggests that obstructive symptoms continue in up to 20% - 30 % of these operations for one of two reasons. The first reason is that there can be persistent septal deformity. Secondly, other valve areas might have been involved but were not addressed at the time of the septal surgery. A commonly overlooked area is the inferior turbinates. In every case, inferior turbinate hypertrophy should be suspected and addressed at the time of septoplasty. Many different approaches to the surgical management of enlarged inferior turbinates have been used, ranging from total turbinectomy to the injection of steroids. Total inferior turbinectomy has been condemned for many years because some authors believe that it has long term sequelae such as rhinitis secca, atrophic rhinitis, and ozena. These terms are often used interchangeably in our literature to describe a dry, crusting nose. This association dates from the 1930's when total inferior turbinectomy was performed as part of a drainage procedure for chronic maxillary sinusitis. Many cases during that era developed atrophic rhinitis because almost the entire lateral nasal wall was removed. Very few studies in the antibiotic era have documented atrophic rhinitis after total inferior turbinectomy. The reverse is actually true. Three separate, large studies involving a total of over 400 patients failed to document a case of atrophic rhinitis after total inferior turbinectomy. A less radical procedure, partial resection of the inferior turbinate (PRITs), is the procedure of choice. It addresses only the area of the inferior turbinate that is anatomically important in the pathogenesis of nasal obstruction, the anterior two centimeters of the inferior turbinate. Fanous and coworkers, in a study involving over 200 patients, indicated that it is only this anterior region that causes the obstructive symptoms. Fanous found that the removal of the anterior two centimeters of the inferior turbinate relieved the obstructive symptoms in 96% of the cases. Lenders and Persig verified these results using acoustic rhinometry to identify the area of obstruction. They found that only the anterior two centimeters of the inferior turbinate was involved in significant obstructive symptoms. Finally, it should be remembered that the inferior turbinates are important in the creation of normal turbulent air flow within the nose. Complete resection risks upsetting the delicate balance between turbulent and laminar air flow without providing better symptomatic relief when compared to more conservative techniques. Case Presentation A 43-year-old male who worked as a fire fighter, presented for evaluation of sinus problems and nasal congestion that had plagued him for many years. Since he was a teenager, he had noticed difficulty breathing through both sides of his nose, but the right side had always been worse than the left. He denied direct trauma to the nose but had participated in numerous contact sports. There was no history of epistaxis, allergies, previous surgeries, and he took no medications. Clinical examination was significant for a severely deviated anterior septum, and bilateral inferior turbinate hypertrophy. CT scanning confirmed the findings on physical examination but did not reveal evidence of significant chronic sinus disease. The patient underwent a nasal septoplasty combined with partial resection of the inferior turbinates. At one year follow-up the nasal passages were patent, and his chronic obstructive symptoms had greatly improved. Bibliography Adamson JE. Constriction of the internal nasal valve in rhinoplasty: treatment and prevention. Ann Plast Surg 1987;18:114-121. Adamson P, Smith O, Cole P. The effect of cosmetic rhinoplasty on nasal patency. Laryngoscope 1990;357-359. Beeson WH. The nasal septum. Otolaryngol Clin North Am 1987;20:743-767. Cole P. Rhinomanometry 1988: practice and trends. Laryngoscope 1989;99:311-315. Constantian MB. Functional effects of alar cartilage malposition. Ann Plast Surg 1993;30:487-499. Constantian MB. The incompetent external nasal valve: pathophysiology and treatment in primary and secondary rhinoplasty. Plast Reconstr Surg 1994;93:919-933. Courtiss EH. Diagnosis and treatment of nasal airway obstruction due to inferior turbinate hypertrophy. Clin Plast Surg 1988;15:11-13. Courtiss EH, Gargan TJ, Courtiss GB. Nasal physiology. Clin Plast Surg 1988;15:11-13. Courtiss EH, Goldwyn RM. Resection of obstructing inferior turbinates: a 6-year follow-up. Plast Reconstr Surg 1983;72:913. Courtiss EH, Goldwyn RM, O'Brien JJ. Resection of obstructing inferior nasal turbinates. Plast Reconstr Surg 1978;62:249-257. Fanous N. Anterior turbinectomy: a new surgical approach to turbinate hypertrophy: a review of 200 cases. Arch Otolaryngol Head Neck Surg 1986;112:850-852. Gruber RP, Peck GC, eds. Rhinoplasty: State of the Art. St. Louis: Mosby, 1993. Grymer LF, Hilberg O, Pedersen OF, Rasmussen TR. Acoustic rhinometry: values from adults with subjective normal nasal patency. Rhinology 1991;29:35-47. Grymer LF, Holbert O, Elbrond, Pedersen OF. Acoustic rhinometry: evaluation of the nasal cavity with septal deviations, before and after septoplasty. Laryngoscope 1989;99:1180-1187. Grymer LF, Illum P, Hilberg O. Septoplasty and compensatory inferior turbinate hypertrophy: a randomized study evaluated by acoustic rhinometry. J Laryngol Otol 1993;107:413-417. Hilberg O, Grymer LF, Pedersen OF, Elbrond O. Turbinate hypertrophy: evaluation of the nasal cavity by acoustic rhinometry. Arch Otolaryngol Head Neck Surg 1990;116:283-289. Huygen PL, Klaassen AB, de Leeuw TJ, Wentges RT. Rhinomanometric detection rate of rhinoscopically-assessed septal deviations. Rhinology 1992;30:177-181. Jessen M, Ivarsson A, Malm L. Nasal airway resistance and symptoms after functional septoplasty: comparison of findings at 9 months and 9 years. Clin Otolaryngol 1989;14:231-234. Jessen M, Malm L. The spontaneous course of nasal obstruction in patients with normal nasal airway resistance. Clin Otolaryngol 1991;16:302-304. Jones AS, Lancer JM, Shone G, Stevens JC. The effect of lignocaine on nasal resistance and nasal sensation of airflow. Acta Otolaryngol 1986;101:328-330. Jones AS, Wight RG, Stevens JC, Beckingham E. The nasal valve: a physiological and clinical study. J Laryngol Otol 1988;102:1089-1094. Kasperbauer JL, Kern EB. Nasal valve physiology: implications in nasal surgery Otolaryngol Clin North Am 1987;20:699-719. Katz E. Intranasal steroid injection. J Otolaryngol 1985;14:136-138. Kent SE, Reid AP, Brain DJ. Neonatal septal deviations. J Royal Soc Med 1988;81:132-135. Lai VW, Corey JP. The objective assessment of nasal patency. ENT J 1993;72:395-400. Lenders H, Pirsig W. Diagnostic value of acoustic rhinometry: patients with allergic and vasomotor rhinitis compared with normal controls. Rhinology 1990;28:5-16. Mabry RL. Inferior turbinoplasty. Laryngoscope 1982;92:459-461. McCaffrey TV. Nasal function and evaluation. In: Bailey BJ, ed. Head and Neck Surgery - Otolaryngology. Philadelphia: Lippincott; 1993:262-268. McCollough EG. Surgery of the nasal tip. Otolaryngol Clin North Am 1987;20:769-784. Moore GF, Freeman TJ, Ogren FP, Yonkers AJ. Extended follow-up of total inferior turbinate resection for relief of chronic nasal obstruction. Laryngoscope 1985;95:1095-1099. O'Neill G, Tolley NS. Theoretical considerations of nasal airflow mechanics and surgical implications. Clin Otolaryngol 1988;13:273-277. Ophir D. Resection of obstructing inferior turbinates following rhinoplasty. Plast Reconstr Surg 1989;85:724-727. Ophir D, Schindel D, Halperin D, Marshak G. Long-term follow-up of the effectiveness and safety of inferior turbinectomy. Plast Reconstruct Surg 1992;90:980-987. Rees TD, Baker DC, Tabbal N, eds. Rhinoplasty: Problems and Controversies. A Discussion with the Experts. St. Louis; Mosby, 1988. Rivron RP. Cross-sectional area as a measure of nasal resistance. Rhinology 1990;28:257-264. Samad I, Stevens HE, Maloney A. The efficacy of nasal septal surgery. J Otolaryngol 1992;21:88-91. Sanderson RJ, Rivron RP. The effect of septal surgery of nasal symptoms. Rhinology 1992;30:17-20. Tarabichi M, Fanous N. Finite element analysis of airflow in the nasal valve. Arch Otolaryngol Head Neck Surg 1993;119:638-642. Wood RP, Jafek BW, Eberhard R. Nasal obstruction. In; Bailey BJ, ed. Head and Neck Surgery Otolaryngology. Philadelphia: Lippincott; 1993:302-328. Grand Rounds Archive | Department Home page BCM Public | BCM Intranet | Privacy Notices | Contact BCM | BCM Site Map | ©2001-2006 Baylor College of Medicine
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