Nasal polyposis: microsurgical ethmoidectomy and interruption of autonomic innervation vs conventional surgery

Nasal polyposis is an invalidating disease which develops through chronic inflammation which leads to tissue oedema and eventually polyps. Treatment is aimed at eliminating polyps, resolving rhinitis symptoms, re-establishing nasal breathing and olfaction and preventing recurrence. The pathogenesis can be explained, in part, by degranulation of mast cells and release of mediators attracting eosinophils which, in turn, can cause tissue damage and oedema. Neurovascular reflexes and factors related to the complex anatomy of ethmoidal labyrinth may be responsible for the onset and persistence of oedema. This would offer a rationale to treatments modifying ethmoid anatomy and blocking neurovascular reflexes in the management of nasal polyposis. The advent of microsurgery and of diagnostic and operative endoscopy has led, over the last twenty years, to earlier detection and to less traumatic and more precise surgical treatment of nasal polyps. With these techniques resection of parasympathetic innervation is also possible, which is in keeping with the proposed rationale and cannot be easily achieved by conventional surgery. To evaluate the impact of this resection on the management of nasal polyposis a review of data has been made in a series of patients with diagnosis of nasal polyposis established by clinical examination, resistant to pharmacological therapy and treated between 1983 and 1998 at the Oto-Neuro-Ophthalmology Department of Florence University (Italy). Patients were treated by conventional surgery (386 cases), by microsurgery without resection of the parasympathetic component of the vidian nerve (97 cases), or by microsurgery with resection of this latter component (94 cases). The rate of recurrence and of major post-operative complications, respectively, were: 39.9% and 4.4% for patients treated by conventional surgery; 37.1% and 6.2% with microsurgery without resection of parasympathetic innervation; and 25.5% and 2.1% with resection of this innervation. The difference in recurrence rate between the three groups was significant (p < 0.05). The average disease-free interval was 45.7 months with conventional surgery and 53.5 months with microsurgery (regardless of resection of innervation). Results show that microsurgery for nasal polyposis together with resection of parasympathetic innervation improves results compared to those with conventional surgery and does not cause an increase in post-operative complications.