Empty nose syndrome (ENS) is a controversial clinical entity with no consensual definition. It is thought to be a postsurgical, iatrogenic (physician caused) phenomenon secondary to loss of nasal turbinate tissue.
The condition was first described by Kerin & Moore in 1994.
The exact incidence of this condition is unknown. Houser et al in their study have quoted 20% as the incidence of ENS following inferior turbinate resection.
Houser et al classified empty nose syndrome into two, based on the resected nasal turbinate into those with conchal mucosal defect (of Inferior, Middle, and both turbinates) and those with normal turbinate structure.
Pathophysiology
The exact pathophysiology of this condition is poorly understood. The proposed theories are:
- Loss of normal physiological nasal function: Humidification, warming, and cleansing of inhaled air is the normal physiological function of the nose. Surgical removal of nasal turbinates will alter this normal physiology due to the reduction in a mucosal area along with proportional loss of sensile, tactile and thermal receptors in the nasal cavity. This will leads to decreased humidification, increased warming, and reduced nasal airflow and resistance.
- Role of cold thermoreceptors (TRPM8): These are thermoreceptors present normally on inferior turbinate of the nasal cavity which helps in reducing the temperature of inspired air. These receptors have a central connection to the respiratory center in the brain. When these receptors are functioning, they lower the temperature of the inspired air. The brain interprets these low temperatures as open airways and reduces the work of respiratory muscles. When these receptors are damaged, feeling of nasal obstruction happens and increased activity of respiratory muscles happens.
- Some authors suggest autonomic neuropathy due to damage to nerve fibers during surgery as a cause, which will eventually lead to mucosal atrophy and ENS.
- Certain authors associate poor regeneration capability of sensory nerve endings at conchal surfaces as the reason for the development of ENS.
- Drying of nasopharyngeal mucosa due to flow of insufficiently humidified air can worsen the symptoms.
- Other theories like atrophy and destruction of the nasal mucosa, central involvement are currently under study.
These functional and compositional changes in nasal mucosa can lead to structural changes. The loss of normal mucociliary function over turbinates leads to nasal crusting.
The nasal cavity becomes unphysiological and abnormally wide. This reduces the sensation of airflow and nasal regulation mechanism.
Etiology
Empty nose syndrome affects certain patients after nasal or sinus surgery, and particularly after inferior turbinectomy.
ENS is mostly reported after turbinectomy, usually after partial turbinectomy.
The onset is usually months or years after inferior and/or middle turbinate surgery.
Clinical features
Empty nose syndrome was long assimilated to an iatrogenic form of atrophic rhinitis with both showing same symptomatology – paradoxical sensation of obstruction, nasal suffocation, nasal burning, crusting, nasal dryness and impaired air sensation through the nasal cavity.
The most common symptom is paradoxical nasal obstruction despite objectively permeable cavities. There won’t be any obstacles found in the nasal cavity on clinical examination, imaging, rhinomanometry or acoustic rhinometry.
Nasal symptoms include subjective feeling of nasal stuffiness, emptiness, sneezing, anosmia/hyposmia, hoarseness and cough (due to inadequate air humidification and purification), facial and nasal pain (due to cold air hitting the area of sphenopalatine ganglion), rhinopharyngeal dryness, hypersensitivity to cold air, sensation of excessive/lack of airflow, headache etc.
The respiratory symptoms include a feeling of suffocation, shortness of breath, tachypnoea, dyspnea, compensatory hyperventilation.
During expiration nasal resistance plays a major role in the opening of terminal bronchioles and optimizing alveolar ventilation. As intranasal pressure decreases, the airflow rate diminishes during inspiration and expiration. However, because of a low airflow rate (within the same inspiring effort) as well as a lack of airflow sensation, an ENS patient begins to experience a feeling of suffocation and other physical and cognitive symptoms, forcing the activation of the sympathetic nervous system (nasal apoplexy), anxiety and forced breakout of breathing, which becomes unstable.
Autonomic symptoms and other general symptoms include loss of concentration, fatigue, anxiety, irritability, depression, panic attacks.
Some patients also complain of difficulty falling asleep.
Because of the severity and debilitating nature of these symptoms, many ENS patients also struggle with mental health issues and the condition is frequently associated with possible psychosomatic pathology (fibromyalgia, functional colopathy), psychological stress, tinnitus, etc.
On the evaluation of these patients, the clinical picture appears similar to that of atrophic rhinitis with loss of normal endonasal anatomy, and in particular with the absence of one or more turbinates, wide nasal cavity due to resection of turbinates, pale and dry mucosa with crusting, etc.
A similar condition which mimics Empty nose syndrome is atrophic rhinitis.
Diagnosis
The diagnosis of Empty nose syndrome is usually difficult. This is because of a lack of consensual clinical definition, variety of symptoms and associated psychological and sometimes social distress. Hence diagnosis is mainly on the clinical basis – based on subjectively reported symptomatology and clinical examination based on nasal cavity endoscopy.
Velasquez et al have developed the Empty Nose Syndrome 6-item Questionnaire (ENS6Q) for subjective testing. The ENS6Q comprises 6 common ENS symptoms (nasal suffocation, nasal burning, nasal openness, crusting, dryness, and impaired air sensation through nasal cavities) related questions, each scored from 0 (least severe) to 5 (most severe).
SNOT 20/Modified SNOT 25 questionnaires can be used to assess the impairment of patient quality of due to ENS.
As an objective test, the diagnosis can be confirmed by placing a piece of moist cotton in the nasal cavity for 20-30 minutes. Alleviation of symptoms confirms the diagnosis.
Certain investigations like imaging (CT nose and PNS) shows mucosal thickening and maxillary opacity in 50% cases.
Rhinomanometry will help to rule out any obstruction, demonstrating weak or absent nasal resistance.
A functional MRI will help in assessing specific activation patterns in temporal, cerebellar and amygdala region.
Treatment
The main treatment of empty nose condition is by prevention. Turbinate conservation in Endoscopic sinus surgeries & rhinoplasty should be considered. Lasers, electric cautery, partial turbinectomy, submucosal turbinoplasty, submucosal resection, radiofrequency surgery etc can be considered for this.
Once diagnosed, medical treatment is by nasal lavage with physiological saline or sulfur derivatives can be offered. Nasal douching, Nasal hydration ointments, Humidifiers, Topical antibiotics, aerosols, Corticosteroids etc are also tried with limited success rates.
Adding menthol to local treatments provides benefits in terms of the sensation of nasal obstruction.
Surgical treatment for ENS aims to reduce nasal cavity volume so as to increase resistance to airflow. This will reduce airflow and increase airs humidity. It will also deviate airflow from the surgical site towards the healthy or non-operated site. This is achieved by placing an implant on septum, floor or lateral wall.
Recently endonasal microplasty by creating a neo-turbinate has been tried. There are various techniques for the microplasty like by doing submucosal implantation of a turbinal or septal cartilage graft to restore inferior turbinate volume. Various exogenic materials like hydroxyapatite, Goretex, Teflon, plastipore have also been tried with satisfactory results.
Injection of hyaluronidase acid gel also seems to improve symptoms in some patients.
Submucosal acellular dermis grafting, platelet-rich plasma injection etc. shown good results are also some treatment options which have shown encouraging results. But these treatment options are possible only when there is some residual turbinate. The limitation is that there exist no randomized studies on this therapy.
Psychological disturbances are very common in ENS patients and they should be provided with proper care and support too. A recent study by Manji et al concluded as follows – “ENS individuals carry a clinically significant psychological burden and experience marked difficulties with many activities of daily living. A multimodal approach to address the tissue loss with surgery and cognitive‐behavioral therapy for the psychological burden may provide the most optimal outcome”.
References
- Houser SM. Surgical treatment for empty nose syndrome. Archives of Otolaryngology–Head & Neck Surgery. 2007 Sep 1;133(9):858-63.
- Saafan ME, Hegazy HM, Albirmawy OA. Empty nose syndrome: etiopathogenesis and management. The Egyptian Journal of Otolaryngology. 2016 Jul 1;32(3):119.
- Coste A, Dessi P, Serrano E. Empty nose syndrome. European annals of otorhinolaryngology, head and neck diseases. 2012 Apr 30;129(2):93-7.
- Scheithauer MO. Surgery of the turbinates and “empty nose” syndrome. GMS current topics in otorhinolaryngology, head and neck surgery. 2010;9.
- Manji J, Nayak JV, Thamboo A. The functional and psychological burden of empty nose syndrome. In International forum of allergy & rhinology 2018 Feb 14.
- Velasquez N, Thamboo A, Habib AR, Huang Z, Nayak JV. The Empty Nose Syndrome 6-Item Questionnaire (ENS6Q): a validated 6-item questionnaire as a diagnostic aid for empty nose syndrome patients. Int Forum Allergy Rhinol. 2017;7:64–71.