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NASAL POLYPOSIS
M V Kirtane*, Prathamesh S Pai **
Honorary Professor and Surgeon, Seth G. S. Medical College and K.E.M. Hospital, Parel, Mumbai. Honorary Consultant ENT Surgeon, P.D. Hinduja National Hospital and Research Centre, Mahim, Mumbai. **Clinical Fellow, Tata Memorial Hospital, Parel, Mumbai
Nasal polyps are pearly white, painless, prolapsed, pedunculated parts of the nasal mucosa. Depending on the sinus of origin, they can be ethmoidal or antral. Ethmoidal polyps are chiefly allergic in origin. Nasal polyposis present with nasal obstruction, discharge, headache, sneezing and occasional epistaxis if severely infected. Their extent can be best evaluated by CT scans. In case of ethmoidal polyposis, conservative treatment can be given in the form of oral and topical steroids, antihistaminics and decongestants. Cases refractory to conservative treatment can be dealt with surgically by performing functional endoscopic sinus surgery. This is the treatment of choice as it is minimally invasive, is performed under direct vision and meticulous clearance is achieved. Precise postoperative care which includes nasal douching, regular follow up endoscopy and topical steroids is essential for achieving control.Introduction
The word "polyp" which is originally Greek has undergone latinization and means [poly-pous] many footed. Nasal polyps are defined as pearly white, painless, prolapsed pedunculated parts of the nasal mucosa. They are unique in their position and their composition. Tomes have been written over these benign growths for centuries, from ancient India when polyps as an entity were recognised through the era of Hippocrates. Hippocrates [BC 460-370] devised a unique method of removing the polyps by passing a string through the nose into the nasopharynx. To this string, a sponge was attached and then it was pulled out through the nose removing the polyps before it. [1] Since then, we have come a long way where mechanised power tools such as microdebriders are used to clear polyps under direct vision.Aetiology
1. Bernouilli’s Phenomenon
Many theories have been put forth regarding the aetiology of polyps, all of which may probably contribute to polyp formation:
Pressure drop next to a constriction causing suction effect pulling the sinus mucosa into the nose.2. Polysaccharide changes
Postulated in 1971 by Jackson and Arihood, [2] an alteration in the polysaccharides of the ground substance, as a cause.3. Infection
Recurrent infection of the sinuses predisposing the mucosa to polypoid changes.4. Allergy
Allergy has been implicated as a cause, since the nasal secretions contain eosinophils, and patients have signs and symptoms of allergy, often associated with asthma [3] and atopy.5. Vasomotor theory
Autonomic imbalance has been suggested as a possible cause in non-atopic individuals.Also implicated are inflammatory mediators, environmental factors, local anatomical factors, Woakes disease and tumours. Genetic predisposition is known to cause polyposis as in cystic fibrosis.
Types
Nasal polyposis can occur in any of the paranasal sinuses and can be unilateral, bilateral, single or multiple.Antrochoanal polyps are usually single, unilateral polyps arising from the wall of the maxillary antrum, prolapsing into the nasal cavity through the maxillary ostium and into the nasopharynx through the choana. Rarely, one may encounter bilateral antral polyps (Figs. 1,2,3).
Fig 1 : Coronal CT Scan showing bilateral antral polyps.
Fig 2: Coronal CT Scan showing antral polyp extending into the nasal cavity.
Fig 3 : Coronal CT Scan showing anthrochoanal polyp extending into the choana.
Ethmoidal polyps are multiple, bilateral polyps arising from the ethmoid sinuses from the middle and superior meatus (Fig. 4).
Fig 4 : Endoscopic photograph of ethmoidal polyps. Sphenoidal and frontal sinus disease is usually associated with ethmoid polyps. Rarely, extensive untreated nasal polyposis may extend beyond the confines of the sinuses into the cranium or the orbit leading to intracranial or orbital complications (Fig. 5).
Fig 5 : Sagittal MR Scan with intracranial extension of extensive nasal polyps.
Clinical Features
Nasal polyposis is a disease affecting the adults. When children below 10 are affected, cystic fibrosis needs to be ruled out. [4]Most patients suffer from nasal obstruction, sneezing, loss of smell and taste, nasal discharge, headache and facial pain, hyponasal voice, postnasal drip and cough. Patients with very severe polyposis may also, present with obstructive sleep apnoea. Asthma and aspirin sensitivity may be present in patients with ethmoidal polyps
Unilateral nasal obstruction may be present in patients with an antrochoanal polyp. Sphenoidal polyposis may present with persistent headaches and infra-orbital neuralgia.
Differential Diagnosis
1. Encephalocoele / Meningocoele
They present immediately after birth, commonly seen in children less than 2 years. The patient may present with a subcutaneous swelling on or lateral to the nasal bridge or with an intranasal mass with impulse on crying / cough. Hypertelorism may also be present.2. Inverted Papilloma
Normally presents in the fifth decade of life with a male predominance. It is usually present on the lateral wall of nose. Malignant change occurs in 2 to 5% of cases whereas 5 to 10% cases are simultaneously malignant.3. Rhinosporidiosis
This lesion caused by the fungus rhinosporidium seeberi presents as a unilateral granulomatous mass and is usually attached to the floor or the lateral nasal wall. It has an unusual ‘strawberry’ appearance.4. Hypertrophied Turbinate
The inferior turbinate may sometimes be engorged and hypertrophic and appear as a polyp to the casual observer. This will shrink with decongestants whereas a polyp will not.5. Concha Bullosa
This is the pneumatisation of the middle turbinate. It presents as an enlargement of the middle turbinate. Diagnosis may be confirmed with CT scan or nasal endoscopy.6. Tumours
These present as fleshy masses causing nasal obstruction, epistaxis, and epiphora. They bleed on touch. CT scan with may show bone erosion and the lesions are usually contrast enhancing.Investigations
Routine haematological testing may show eosinophilia. Special tests may include a nasal smear for eosinophils in nasal secretions; RAST[radioallergosorbent test]; skin prick test; IgE, IgG levels and sweat tests for cystic fibrosis. Ciliary dysfunction tests include ciliary beat frequency, electron microscopy of cilia and nasal mucociliary clearance.Radiological assessment is extremely important in all cases of nasal polyposis. The information obtained through conventional x-rays taken in the Water’s view and the Caldwell’s view is limited. The advent of computed tomographic scanning (CT scan) has revolutionised the understanding of the disease. CT shows the exact site, extent and variation in anatomy offering a road map for the surgeon. Even a virtual endoscopy is now possible with the aid of new software.
Treatment
The treatment of nasal polyps differs according to their type. Antrochoanal polyps are surgically treated whereas ethmoid nasal polyps merit a combined modality of treatment.Antrochoanal Polyps
The antrochoanal polyps have to be treated surgically. Since these arise from the maxillary antrum, they were earlier removed either by simple polypectomy or by the Caldwell-Luc procedure. Today, the preferred treatment is transnasal endoscopic removal. This method involves removal of the uncinate process of the middle meatus, widening of the natural ostium of the maxillary sinus and removal of the polyp under direct vision. Co-existing ethmoidal disease is then cleared. There are several advantages of endoscopic removal over the Caldwell-Luc technique. The antral part may be removed in continuity with the nasal and choanal segment of the polyp. Co-existing ethmoidal disease is cleared at the same time. Accessory ostia are connected, thus preserving functional integrity of the sinuses without residual disease and extensive surgery. Disadvantages of the Caldwell-Luc operation like facial swelling and dental neuralgia can be avoided.Ethmoid polyps
The ethmoid polypoid disease is essentially an allergic condition. Early polyposis may respond to medical treatment, but well established polyposis will require surgical treatment. Recurrences are common since the underlying cause is nasal allergy and a regular follow up endoscopic examinations are mandatory to recognise such recurrences early and treat them on OPD basis.Medical Treatment
The treatment comprises antibiotics to control local infection, decongestants and steroids. The polyps may respond favourably to local steroid therapy.Local steroids, which are commonly used, are betamethasone, beclomethasone, budesonide and fluticasone. Steroid sprays and inhalants are relatively safe and can be used over prolonged periods of time without disturbing the hormonal balance in the body. In post-operative periods the local steroids aid in faster mucosal healing and prevent recurrence of the polyps. [5] Short courses of oral steroids may be used routinely or in cases of resistant or extensive polyposis to control the disease.
The medical treatment gives immediate symptomatic relief and in some cases totally controls it.
Surgery
Surgery is indicated when:
- Medical therapy fails to control significant symptoms with repeated or prolonged courses of steroid and antibiotic therapy
- Disease exists in a patient who is not a candidate for oral steroids
- There is persistent infection or complications of sinus disease such as mucocoele.
- Total nasal obstruction occurs
For over a century the surgical line of treatment in case of polyposis varied. The simplest technique was trans-nasal polypectomy using nasal snares under direct vision. Intranasal ethmoidectomy was also done, but was associated with a high incidence of surgical complications and recurrence rates were high. External ethmoidectomy is safer, but has the disadvantage of a scar on the face. Trans-antral ethmoidectomy was done rarely. The Caldwell-Luc operation is still done occasionally for antral polyps. Extensive polyposis, especially when involving the frontal sinus may require a fronto-ethmoidectomy, or a frontal osteoplastic flap
The procedure of choice is an endoscopic clearance of the polyps and affected sinuses. The sinuscope aids in better visualisation and complete clearance of disease. The basic steps of endoscopic sinus surgery (ESS) for nasal polyposis involve, uncinectomy followed by removal of anterior and posterior ethmoidal cells along with polyps. The maxillary ostium is then widened to facilitate maxillary sinus clearance. Similarly, the frontonasal recess is cleared. The sphenoid sinus may also be cleared if required. [5] With ESS, it is now possible to achieve an excellent result (Figs. 6a, 6b). In cases of refractory and extensive nasal polyposis, a total sphenoethmoidectomy followed by long-term postoperative topical steroid therapy provides improvement or cure with safety and reliability. [6] Optical tracking and intraoperative interactive imaging integrated with endoscopy allows localisation of anatomic landmarks and better clearance of polyps during ESS. [7] Not every case merits all these steps. Surgery is tailored to suit the disease.
ESS is minimally invasive, the removal is under direct vision and meticulous clearance with preservation of function is possible. Complete removal of polyps, precise post-operative care and adjuvant medical therapy, results in reduced recurrence rates. Satisfactory olfaction may be regained in a significant number of cases. [6]
Fig 6A Preopeartive coronal CT scan showing bilateral ethmoid polyposis. Fig 6B: Postoperative cpronal scan showing cleared ethmoid cavity. Post Operative Care
Postoperative care has to be aggressive. Clearance of debris with suction and / or nasal douching will prevent persistence of infection and synechiae formation. These are important features in postoperative care for a patient who has undergone functional endoscopic sinus surgery. Topical steroids are given for 3 weeks to 3 months for control. Adjunctive treatment in form of decongestants and antihistaminics gives added benefit. Regular diagnostic examination of the nasal passages with help of a sinuscope will help detect early polyp recurrence, which can be treated as an office based procedure under LA.Causes of failure
We must remember that we are treating an essentially medical disorder by surgery. Since allergy is often the root cause, high recurrence rates remain a feature of allergic nasal polyposis. Other causes of failure include inadequate surgery, aggressive nature of polyps, predisposing local factors or improper post operative care. ASA hypersensitivity spells poor prognosis.Nasal polyposis is a recurrent disease that may be very frustrating to both the patient and the physician. Combined medical and surgical management with regular follow up provides the best chance to the patient of a long-term symptom free state.
REFERENCES
- Vancil ME. A historical survey of treatment of nasal polyposis. Laryngoscope 1969; 79 : 435-445.
- Jackson, RJ, Arihood, SA. The acid mucopolysaccharides and collagen content of human nasal polyps, and perinasal mucosa. Annals of Otolaryngology 1971; 80, 586-592.
- Sin A, Terzioglu E, Kokuludag A, Veral A, Sebik F, Karci B, Kabakci. T Allergy as an etiologic factor in nasal polyposis. J Investig Allergol Clin Immunol Jul-Aug. 1997; 7(4): 234-7.
- Triglia JM, Nicollas R, Roman S, Dessi P. Naso-sinusal polyposis in children. Mid-term results of sinusal surgery. Ann Otolaryngol Chir Cervicofac 1997; 114(7-8) :267-71.
- Kirtane M.V. Monograph on Functional Endoscopic Sinus Surgery. 1993.
- Klossek JM, Peloquin L, Friedman WH, Ferrier JC, Fontanel JP Diffuse nasal polyposis: postoperative long-term results after endoscopic sinus surgery and frontal irrigation. Otolaryngol Head Neck Surg Oct. 1997; 117(4): 355-61.
- Hsu L, Fried MP, Jolesz FA. MR-guided endoscopic sinus surgery. Am J Neuroradiol Aug 1998; 19(7):1235-40.
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