Upper respiratory infections are the most frequent cause of impaired nasal patency in children. A properly functioning nose is of vital importance for the child´s normal mental and physical development. In view of this, an effective treatment of these conditions is a social obligation for every doctor. A varying local or general immunity, depending on the developmental age, variable physical environment in which the young patient lives, and congenital or acquired deformities of the nasal skeleton are responsible for more frequent, persistent, or chronic upper respiratory infections. One of the deformities is deviation of the nasal septum, in which case an extended surgical treatment is widely available in many laryngological centres. Other conditions include anatomical dissimilarities of the lateral nasal wall. They are the most controversial issues since corrective techniques in this case have been used for a relatively short time. The initial period in the extensive use of the endoscopic methods in the correction of lateral nasal wall deformities in children was observed in the 1990´s. However, that period of optimism was followed by a period of critical assessment of the endoscopic treatment. The current criteria are based mainly on animal studies, therefore they are of limited value. This is due to the fact that the functioning of most structures of the human nose is dependent on the vertical position of the human body. In this respect, an animal subject may only serve as no more than a good experimental model. In view of the above, it seems that reports of results obtained in animal studies should be, at best, published only on a limited scale.

Patients should be selected for surgery only when they have satisfied a number of essential criteria. The first one is a careful radiological diagnosis. Computer tomography of the sinuses should be done prior to any operation since it will provide answers to many questions:

1. What is the relationship between the uncinate process and the orbital lamina of the ethmoid labyrinth? Can the removal of the process lead to the opening of the orbit?

2. Is the maxillary sinus well-developed? (An incompetent radiologist may describe an undeveloped sinus as an opaqueness of the sinus).

3. Are the accessory ostia of the maxillary sinus (fontanels) present?

4. Are Haller´s cells visible on the sinus scans?

5. What is the position of the frontal recess?

6. Are the frontal sinuses symmetrical?

7. Is the ridge of the nose pneumatized?

8. Is there any evidence of previous sinus surgery?

9. How to demonstrate the ethmoid cells adjacent to the orbital apex?

10. Is the middle nasal concha pneumatized?

11. Is the roof of the ethmoid cells clearly visible?

12. How much lower is the ethmoid lamina situated in relation to the top of the ethmoid sinus?

13. What is the configuration of the basal lamina of the middle nasal concha?

14. Is it possible to identify the location of the anterior ethmoidal artery?

15. Is it possible to assess the location of the internal carotid artery and optic nerve in relation to the lateral wall of the sphenoid sinus?

16. Is the sphenoid sinus symmetrical?

When inflammatory lesions in children are complicated by eyelid oedema, it is also vital to assess how and to what extent the lesions have penetrated from the sinuses into the orbit. CT examination of the sinuses should provide evidence of inflammatory infiltration, subperiosteal abscess, or orbital abscess in the orbit.

The above-mentioned elements of radiological evaluation of the nose and sinuses can and should give the surgeon indications as to the neccesary extent of the sinus ostium reconstruction and the excision of lesions (e.g. a polyp or neoplasm). It is generally known that not all radiologically recognised deformities require surgical management. Since they are frequent, and may produce no clinical manifestations, they may be assessed as developmental anomalies in many cases.

Preparation of young patients for sinus surgery requires an exceptionally thorough assessment of their general condition. Endoscopic operations must be performed under general anaesthesia, which carries an increased risk of bleeding during the surgical procedure. Only children with normal blood cell count and coagulation values may undergo this type of surgery. The operating theatre should be provided with appropriate equipment to control bleeding (e.g., argon plasma coagulation device). Other equipment (e.g., a suction-irrigating optical cover) should also be available to allow the surgeon to proceed with the operation in the case of severe bleeding.

Due to their radical character, conventional methods of endoscopic operation on the nose, described by Stammberger and Wigand, are not always appropriate for children at the developmental age, therefore many paediatric laryngological centres have developed surgical protocols to treat patients at that age.

The main principle is to ensure that surgical operations are performed only in the centres where equipment suitable for young children is available.

Instruction in endoscopic sinus surgery in paediatric patients should be provided only to laryngologists with previous surgical experience in adult patients. They should further be instructed by an experienced laryngologist in a paediatric otolaryngological centre.

Endoscopic operations in children should be performed only on those structures of the nose and paranasal sinuses where lesions are amenable to surgical treatment.

At present, there are many world centres satisfying the above requirements, and their experience and achievements have also been reported in literature.

Own experience and data available in laryngological literature allowed the surgeons at the Department of Paediatric Otorhinolaryngology, to develop a technique to minimise the extent of endoscopic nasal operations in children.

The main principle is a thorough endoscopic examination of the nasal cavities, especially the lateral nasal wall. The extent of any operation should be limited to the necessary minimum; this means that the objective must be confined to the removal of lesions (e.g., nasal polyps) and the improvement of paranasal sinus ventilation in chronic sinusitis). The operation should not be extended beyond these limits. Surgical operations usually consist of the excision of the uncinate process, evaluation of the maxillary sinuses, and endoscopic examination of the frontal recess and the ostia of anterior ethmoid cells. In some cases, the procedure is extended onto other affected structures. The endoscopic approach to the frontal sinus in a child should not be used as a general principle, because there is a risk that the delicate physiopathological structure of the frontal sinus ostium may suffer damage during the procedure, which may consequently result in a chronic inflammatory process in the frontal sinus. Therefore, if an operation on inflammatory or neoplastic lesions in the sinus is required, an external surgical approach should be employed. This allows the surgeon to precisely control the whole frontal sinus, and to use the endoscopic approach from the nasal cavity towards the frontal recess without destroying the sinus ostium (apart from few exceptional cases).

Ethmoiditis with orbital complications in children requires an external approach, because it is the only way to obtain an effective drainage of any purulent discharge, and to provide the best protection against the risk of blindness. Frequent recent reports of cases of orbital abscess drainage in children using endoscopic methods should be used only in exceptional situations.

Using the material consisting of 57 children with orbital complications of acute ethmoiditis, and 159 patients with chronic sinusitis we assessed the possibilities, risks, and outcome of sinus surgical operations in paediatric patients. (Tables 1a and 1b).

A total of 165 patients (159 children including 6 re-operations)underwent endoscopic surgical sinus operations at the Department of Paediatric Otorhinolaryngology, Medical University of Warsaw, between 1995-2003. The study group consisted of 93 males and 66 females. The age ranged from 3 years to 18 years (mean 10.4 years). The mean postoperative follow-up time was 3 years and 6 months. (Tables 2, 3).

The extent and the number of particular operations is shown in Table 4. The largest number of operations included evaluation of maxillary sinuses with or without excision of lesions (162 operations), and endoscopic dilation of the natural maxillary sinus ostium by excision of the uncinate process (157 operations).

Three boys required reoperation for nasal and sinus polyps (one case) and a recurrent choanal polyp (the second case).

The above material and literature reports show that when a young patient requires surgical treatment of paranasal sinus disease, the surgery should be performed. Caldwell-Luck´s approach should not be used in patients at the developmental age because of a likely damage to the tooth buds during this procedure. Therefore, an endoscopic approach is the method of choice. Performed by an experienced surgeon in a properly equipped operating theatre, the operation carries a risk of complications, but not performing the operation may produce considerably more severe complications. Many years of individual professional experience and data from the clinical literature have encouraged us to suggest that minimising functional endoscopic sinus surgery in children is, in many cases, the only means of effective treatment of chronic inflammatory lesions in this particular anatomical region area, including removal of neoplasms or biopsy specimen sampling, and reconstruction of posttraumatic abnormalities.