Empty nose syndrome
Encyclopedia
Otolaryngology
Otolaryngology or ENT is the branch of medicine and surgery that specializes in the diagnosis and treatment of ear, nose, throat, and head and neck disorders....
to describe a nose
Human nose
The visible part of the human nose is the protruding part of the face that bears the nostrils. The shape of the nose is determined by the ethmoid bone and the nasal septum, which consists mostly of cartilage and which separates the nostrils...
that has been physiologically crippled by excessive surgical removal of turbinates in the nose (mainly the inferior turbinates) in a surgical procedure known as 'turbinectomy
Turbinectomy
Turbinectomy is removal of some or all of the turbinate bones of the nose attached to mucous membranes. It has been used to relieve nasal obstruction, but side-effects include removal of nerves that would report the passage of air....
' or 'conchotomy'. It is therefore an iatrogenic condition that can and should be avoided.
Main symptoms
The two main physical symptoms are:- Chronic nasal dryness Often leads to chronic mucosal inflammationInflammationInflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
and pain. Chronic inflammation can cause areas of the mucosa to atrophyAtrophyAtrophy is the partial or complete wasting away of a part of the body. Causes of atrophy include mutations , poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply to the target organ, disuse or lack of exercise or disease intrinsic to the tissue itself...
and this is why some studies refer to this condition as "secondary atrophic rhinitisAtrophic rhinitisChronic atrophic rhinitis is a chronic inflammation of nose characterised by atrophy of nasal mucosa, including the glands, turbinate bones and the nerve elements supplying the nose. Chronic atrophic rhinitis may be primary and secondary...
". At least one large study concluded that it can take 7.1 years, on average, for symptoms of atrophic rhinitis to appear and urges the examining physician to look for early signs and to try to counter them with self administered daily nasal irrigations and moisturization by the patient. - Paradoxical obstruction - a constant troubling feeling of suffocation generated by poor airflow feedback from the nasal mucosa, either because of atrophy of the trigeminal nerve endings that are supposed to generate this sensation, their lack of responsiveness because of the mucosa becoming too dry or going through metaplasiaMetaplasiaMetaplasia is the reversible replacement of one differentiated cell type with another mature differentiated cell type. The change from one type of cell to another may generally be a part of normal maturation process or caused by some sort of abnormal stimulus...
, or simply because of the loss of normal nasal aerodynamics following the turbinectomy. Without good and constant airflow sensation of the air flowing through the nose, the nervous feedback to the central nervous systemCentral nervous systemThe central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...
is that of suffocation.
The chronic nature of the physical symptoms has a significant impact on the patient's quality of life
Quality of life
The term quality of life is used to evaluate the general well-being of individuals and societies. The term is used in a wide range of contexts, including the fields of international development, healthcare, and politics. Quality of life should not be confused with the concept of standard of...
and sense of well-being, causing difficulty concentrating, pre-occupation with symptoms, anxiety
Anxiety
Anxiety is a psychological and physiological state characterized by somatic, emotional, cognitive, and behavioral components. The root meaning of the word anxiety is 'to vex or trouble'; in either presence or absence of psychological stress, anxiety can create feelings of fear, worry, uneasiness,...
, and clinical depression.
Etiology
The turbinates are known as the main humidifying, heat exchanging, air-filtering, airflow controlling and airflow sensing structures of the nose. They control, heat, humidify and filter the airflow by streamlining it around them as it progresses through the nose, thus significantly increasing the mucosal surface that comes into contact with the airflow. Their integrity and function is crucial for maintaining nasal and sinus health and physiology. Built aerodynamically from anterior to posterior they are designed to not over obstruct breathing while processing the airflow.The turbinates play a vital role in protecting the inner nasal mucosa and allowing it to recuperate and regenerate. A normal nose of an adult processes on average 10,000 liters of air in 24 hours, it therefore needs some form of resting period to recuperate and maintain good health and integrity of the delicate respiratory epithelium
Respiratory epithelium
Respiratory epithelium is a type of epithelium found lining the respiratory tract, where it serves to moisten and protect the airways. It also functions as a barrier to potential pathogens and foreign particles, preventing infection and tissue injury by action of the mucociliary escalator.-...
layer that lines the entire nasal airway and sinuses. The recuperation of the nose is achieved by a phenomenon known as the 'nasal cycle
Nasal cycle
The nasal cycle is the alternating congestion and decongestion of the nasal cavities in humans. It is a physiological congestion of the nasal concha due to selective activation of one half of the autonomic nervous system by the hypothalamus. It should not be confused with pathological nasal...
'. Every 3–6 hours one side of the nose congests with blood while the other remains decongested - thus the majority of the workload of breathing is done through the decongested side while the congested side rests and recuperates. When the inferior turbinates are resected the nasal cycle can no longer fully congest the side of the nose where they were resected and therefore much of the natural recuperation capability on that side is lost.
There are typically three pairs of turbinates in the human nose - the inferior concha, the middle concha and the superior concha. Each pair is very different in size and in shape, and each protect a different region of the nasal cavity: The inferior turbinates are the largest and extend all across the lower part of the nasal cavity, from the very front of the nose almost up to the nasopharynx
Nasopharynx
The nasopharynx is the uppermost part of the pharynx. It extends from the base of the skull to the upper surface of the soft palate; it differs from the oral and laryngeal parts of the pharynx in that its cavity always remains patent .-Lateral:On its lateral wall is the pharyngeal ostium of the...
. As the inferior turbinates are the largest and the first to mitigate the inspired air, their loss has the most profound effect on the physiology of the remaining mucosa. The middle turbinates hover above the inferior turbintaes and begin from approximately the mid section of the nasal cavity. They are much smaller and unlike the inferior turbinates harbour some olfactory nerve axons and protect the upper regions of the cavity, in particularly the olfactory bundle of nerves at the roof of the nose and the openings of the ethmoid and frontal sinuses. Their loss will play a lesser role in the over all reduction of the retained heat and humidity in the nose, but it might impact the quality of the sense of smell and the health of the ethmoid and frontal sinuses. The superior turbinates are tiny in comparison to the inferior and middle ones and have the sole role of being the last line of protection around the olfactory bulb.
The loss of too much turbinate tissue may cause the remaining mucosa at the vicinity of the site of resection, and directly behind and above that area, to gradually become more and more inflamed, dry, go through metaplasia
Metaplasia
Metaplasia is the reversible replacement of one differentiated cell type with another mature differentiated cell type. The change from one type of cell to another may generally be a part of normal maturation process or caused by some sort of abnormal stimulus...
, endertitis and eventually atrophy
Atrophy
Atrophy is the partial or complete wasting away of a part of the body. Causes of atrophy include mutations , poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply to the target organ, disuse or lack of exercise or disease intrinsic to the tissue itself...
. As a result all four major functions of the nose become impaired: breathing
Breathing
Breathing is the process that moves air in and out of the lungs. Aerobic organisms require oxygen to release energy via respiration, in the form of the metabolism of energy-rich molecules such as glucose. Breathing is only one process that delivers oxygen to where it is needed in the body and...
, defense, olfaction
Olfaction
Olfaction is the sense of smell. This sense is mediated by specialized sensory cells of the nasal cavity of vertebrates, and, by analogy, sensory cells of the antennae of invertebrates...
and phonology
Phonology
Phonology is, broadly speaking, the subdiscipline of linguistics concerned with the sounds of language. That is, it is the systematic use of sound to encode meaning in any spoken human language, or the field of linguistics studying this use...
. This can take many years to fully develop, which may complicate the proper diagnosis.
Diagnosis
The clinician should suspect ENS when the following findings are present: The patient complains of poor nasal breathing and often a relentless sensation of suffocation or shortness of breath despite having a patent (typically over-patent) nasal airway. The patients typically complain of nasal dryness too. These symptoms appeared only after the patient underwent a turbinate reductive procedure. Sometimes, many years later.On examination the nasal cavity
Nasal cavity
The nasal cavity is a large air filled space above and behind the nose in the middle of the face.- Function :The nasal cavity conditions the air to be received by the other areas of the respiratory tract...
should look abnormally spacious, lacking (part of) one or both turbinates (the inferior and/or middle turbinates). Mucosal pathology varies greatly. In some patients, the mucosa is dry and pale because of metaplasia
Metaplasia
Metaplasia is the reversible replacement of one differentiated cell type with another mature differentiated cell type. The change from one type of cell to another may generally be a part of normal maturation process or caused by some sort of abnormal stimulus...
; in others, it is red because of chronic infection. Crusting may range from absent to severe. The symptoms and findings are believed to be caused by abnormal aerodynamics, chronic inflammation and dryness leading to loss of airflow sensation that feels like dyspnea.
The diagnosis is often complicated because it is common to find that the remaining tissues are hypertrophied (in response to the dryness and constant aggravation of over-turbulent air currents).
Prognosis
There has been very little research conducted on this condition and hardly any long-term follow-ups. For many years this condition was overlooked or mistaken because of secondary problems that usually occur after radical nasal turbinectomies. For instance, the remaining mucosal structures (the septum and the remaining turbinates) often hypertrophy, causing actual physical obstruction on top of the already existing paradoxical obstruction.The lack of long-term follow-ups of patients with this condition makes it difficult to estimate what percentage of patients, if any, will enjoy a spontaneous recovery or at least a significant enough improvement in their symptoms. But, given that the main cause of the symptoms is the gross loss of normal inner nasal anatomy, it is not likely that this condition can cure itself.
Dr. Eugene Kern, who coined the term "empty nose syndrome", claims that this condition often gets worse over the years through increasing wear and tear of the remaining mucosa in the nasal cavity, because the lack of turbinates leaves the mucosa overexposed to unduly patent currents of unfiltered, and under conditioned airflow on every inspiring breath. In fact, he maintains that there is an unknown threshold of loss of turbinate tissue from which the nasal mucosa can not recuperate from the daily onslaught of direct airflow. Kern and Moore conducted a large retrospective study of 242 patients which they carefully examined over several years at the Mayo Clinic in Rochester (MN, USA), all of whom had undergone some form of partial or radical turbinectomy, following which they had developed symptoms of atrophic rhinitis. They called this condition "empty nose syndrome" to depict how unnatural these noses looked in CT findings and upon physical examination. They emphasized how negatively this condition had affected their quality of life and sense of well being and the fact that in many of the patients the symptoms seemed to worsen over the years, indicating further damage and wear and tear due to the loss of turbinate protection, as there was no other cause that could explain this.
Their findings corroborated early conclusions about turbinectomies that were adopted by ENT communities world-wide after these surgeries first started in the late 19th century and are further more supported by several prominent other studies from the late 20th century following patients that had undergone radical inferior turbinectomies, but some supporters of turbinectomies remain unconvinced as there have been several long-term follow-up studies that claim to have found no major long-term ill effect. So, the controversy remains, although the pendulum has nowadays shifted back amongst most nasal surgeons towards the importance of keeping as much as turbinate tissue possible when performing turbinate reductive procedures.
The patients can replace some of the lost moisture to reduce the risks of mucosal atrophy by coating their nasal lining with protective gels and using saline mist sprays and irrigations, but it seems that unless the turbinates are functionally reconstructed there is little hope to fully recover from this condition.
In recent years there have been several reports of attempts to reconstruct the inferior turbinates of the nose through submucusal implantation of various implant materials, in an attempt to restore normal nasal aerodynamics and physiology. The sample of patients reported on was very small and the follow-up was relatively short, but the results show some promise.
There is hope among patients that with recent advances made in regenerative medicine
Regenerative medicine
Regenerative medicine is the "process of replacing or regenerating human cells, tissues or organs to restore orestablish normal function". This field holds the promise of regenerating damaged tissues and organs in the body by replacing damaged tissue and/or by stimulating the body's own repair...
otolaryngologists will begin to explore ways to use stem cells and tissue engineering
Tissue engineering
Tissue engineering is the use of a combination of cells, engineering and materials methods, and suitable biochemical and physio-chemical factors to improve or replace biological functions...
technology to fully reconstruct the inferior turbinates of the nose and restore it back to normal.
Non-surgical treatment
Non-surgical treatment options are meant to maintain and improve the health of the remaining nasal mucosa in the ENS nose by keeping it moist and free of infection and irritation and by maintaining a good blood supply:- Keeping the nasal passages moist with saline based mist sprays or gels.*
- Nasal irrigationNasal irrigationNasal irrigation or nasal lavage or nose douche is the personal hygiene practice in which the nasal cavity is washed to flush out excess mucus and debris from the nose and sinuses. The practice is well-tolerated and beneficial with only minor side effects...
s of regular salineSaline (medicine)In medicine, saline is a general term referring to a sterile solution of sodium chloride in water but is only sterile when it is to be placed intravenously, otherwise, a saline solution is a salt water solution...
(Many patients prefer to use Ringer's Lactate solution with added xylitol instead, as they find it soothes the mucosa more than regular saline, and there are some empirical studies that back up that claim ). - Irrigations of saline with 80 mg of gentimycin if ozena occurs.
- Systemic medication as indicated for pain and or depression which is common (about 50%) in patients with this syndrome.
- Sleeping with a cool mist humidifier.
- Regular daily physical exercise and maintaining good general health to reduce the risk of deterioration of symptoms.
Surgical treatment
The underlying rationale of surgery is to restore the natural inner nasal geometrical contours of the nasal passages of air (the inferior, middle, and superior meatuses), as much as possible, to mitigate the airflow just enough to restore normal rates of inner nasal humidity and temperature that will allow the mucosa to recuperate and sense the airflow well enough. It is paramount to do so while trying to restore the normal aerodynamics of the airflow in the nose, otherwise nasal obstruction will occur.
Pre-surgical planning has a tremendous impact on the success of the procedure. The surgeon is advised to perform a cotton test prior to the implantation: the surgeon places saline soaked chunks of cotton wool at the pre-planned site of implantation to simulate the implant. By doing so, he restricts and normalizes the nasal airflow patterns. This restores nasal aerodynamics. By trying different locations in accordance to the patient's feedbacks regarding the quality of his breathing and other ENS symptoms, it is possible to pinpoint the exact placement for the implants and their estimated shape and size.
Turbinate tissue is unique and there are no potential donor sites in the body from which to harvest similar tissue. However, in the nose, form equals function. It is therefore possible to restore some function by restoring the natural contours and proportions of the nasal passages:
It is possible to create an artificial look-alike structure of a turbinate in the nasal cavities, and thus to regain some of the nose's capabilities to adequately resist, streamline, heat, humidify, filter, and sense the airflow.
Implant materials
Generally speaking, the implant materials can be divided into 3 groups:
- autografts: bone, cartilage, fat, etc. from one site to another in the same patient. The problems here are relative shortage of tissue, and long term studies have shown high absorption rates in the nose. A Chinese study reported long-term success using illiac bone autografts.
- foreign materials: such as fibrin glue, Teflon, Gore-TexGore-TexGore-Tex is a waterproof/breathable fabric, and a registered trademark of W. L. Gore and Associates. It was co-invented by Wilbert L. Gore, Rowena Taylor, and Gore's son, Robert W. Gore. Robert Gore was granted on April 27, 1976, for a porous form of polytetrafluoroethylene with a...
, and plastipore, which solve the problem of shortage of autografts, are easy to shape and do not tend to get absorbed. However they have a high extrusion rate, and sometimes cause infection. A case study of good retention of hydroxyapetite cement in one patient has been reported in 2000, but the follow-up was only 1 year long. - allografts: In the last two decades scientists have been able to harvest and remove away genetic markers of some basic human tissues (like skin dermisDermisThe dermis is a layer of skin between the epidermis and subcutaneous tissues, and is composed of two layers, the papillary and reticular dermis...
) from donors, and thus supplying a human natural implant material which does not stimulate the immune system to reject it. A good example for such material is acellular dermis (brand named "Alloderm"). It does not get rejected and in most areas retains most of its volume over long periods.
The ideal implant material, other than real original turbinate tissue should be something with low extrusion and rejection rates, minimal infection risk, and—very importantly—that will provide a strong and endurable enough structure and at the same time allow good permeability for blood vessel incorporation, which seems to be the key against long term absorption.