**2. Standardization of surgical procedure and treatment protocol**

The first consideration of this study was to select appropriate patients in order to exclude the congenitally influential factor of heterogeneity of CRS. The next consideration was to standardize the preoperative treatment, surgical procedure, and postoperative follow-up protocol. Over the past 10 years, we have developed a standardized surgical procedure and treatment protocol. Preoperatively, the referral doctor administers optimal medical treatment to the patient; if that does not occur, our clinics will administer the treatment. If treatment fails, surgery is suggested. Preoperative medication is not given for at least 2 weeks, if acute exacerbation was not noted before surgery. Some patients are given a loose schedule of intranasal steroid spray, but oral antibiotics are not given regularly.

Other information are also collected during the preoperative visit: age, gender, asthma, nasal polyps, allergic rhinitis, obstructive sleep apnea, diabetes, smoking status, gastroesophageal reflux disease, prior FESS history, and Samter's triad. For the surgical procedure, the objects of FESS include several folds: to clear out the occluded ostium by correcting the anatomical flaw of bottleneck of draining pathway for diseased sinus, to decrease inflammatory load by removing developed polyps or swollen mucosa which was filled with inflammatory milieu, and to clean out entrapped discharge from deep-seated recess which contained inflammationinducing materials. Based on the principles described above, we developed eight complete steps to perform standard FESS:


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*Refractory Rhinosinusitis*

most patients.

*DOI: http://dx.doi.org/10.5772/intechopen.84714*

of the posterior ethmoid sinuses.

a challenging step for beginners.

will be safely opened.

least 3 months.

the lateral margin of the ethmoid cavity.

4.Removal of the bony wall of the ethmoid bulla: Identifying the basal lamella of the middle turbinate. The retrobullar recess and suprabullar cells are exposed. It is important to expose and identify lamina papyracea in order to delineate

5.Removal of the basal lamella at the medial inferior site: In order to enter posterior ethmoid sinus space safely, the middle turbinate insertion is not destabilized. When entering posterior ethmoid space, the superior turbinate and skull base are identified by carefully removing the ethmoid bony septum

6.Opening of the sphenoid sinus, if necessary: The sphenoid sinus is not frequently involved in CRS. If necessary, remove the inferior third of superior turbinate in order to easily find the natural ostium of sphenoid sinus. Irrigation or removing polypoid mucosa surround the ostium is sufficient for

7.Removal of the bony partitions along the skull base: After identifying the skull base at the posterior ethmoid roof, its is safe to remove the partitions anteriorly to reach the bony indentation of the anterior ethmoid artery (AEA), which is the most important landmark to manage frontal recess. The AEA is a landmark ("Nike" logo-shaped curve) and may be buried inside a bony canal in patients with well-pneumatized anterior ethmoid sinuses; it could be mesenteric. This space is complicated by various possible suprabullar or frontobullar cells and is

8.Cleaning frontal sinus-draining route: Using the 45-degree endoscope, mark the anatomic landmark of AEA posteriorly and agger nasi or frontoethmoid cells anteriorly; the frontal sinus-draining route is frequently buried in the complicated anterior ethmoid cell system. There may be anteriorly, posteriorly, medially, and laterally located ethmoid air cells; it is important to identify the boundary of ethmoid cavity laterally to the lamina papyracea, medially to the middle turbinate concha, and superiorly along the skull base. The frontal sinus

Postoperative care includes regularly follow-up for at least 6 months using optimal antibiotic treatment, including low-dose macrolide for 2 months and nasal steroids, as well as routine saline nasal douching plus adjuvant of gentamicin for at

**3. Patient selection, radiographic evaluation, and statistical analyses**

We reviewed the medical records of 243 patients who received bilateral FESS in our department by the same senior surgeon of a tertiary referral hospital from September 2010 to August 2011. Computed tomography (CT) of paranasal sinuses was performed in all patients at most 2 months prior to surgery. Other preoperative evaluations included hematologic examination the day before surgery. Patients with known systemic diseases or malignancies were excluded, such as diabetes mellitus, asthma, or other immunocompromised diseases. Forty-eight CRS patients who received revised sinus surgery during this period were recruited; 21 of these patients received surgery by the same surgeon, and the other 27 patients received surgery from different surgeons. Among the 21 patients, patients with no previous

*Rhinosinusitis*

cannot be precisely correlated. Spatially, the Lund-Mackay (L-M) score, which is based on CT images, is the most frequently used method to evaluate the severity of CRS; nevertheless, the L-M score represents only a snapshot of the condition [7]. A swift change in mucosal swelling is frequently observed during the subacute stage of sinusitis. Other parameters should be considered in order to define the severity

Various factors are related to refractory CRS, including mucociliary dysfunction, the presence of mucosal biofilm, peripheral eosinophil count, mucosal eosinophilia, acute postoperative infection, ASA triad, cystic fibrosis, osteitis, hyperreactive airway, inhaled allergen, and experience of the performing surgeon [8–12]. It is important to find a simple way to evaluate the severity of CRS in order to identify an accurate prognosis for patients and determine which patients may need longterm medical treatment. The aim of the study was to determine the clinical features related to the severity of CRS that would necessitate revision surgery, by carefully

of CRS and more accurately predict its prognosis.

eliminating surgeon bias using standardizing surgical procedures.

steroid spray, but oral antibiotics are not given regularly.

complete steps to perform standard FESS:

saline is frequently applied.

semilunaris.

**2. Standardization of surgical procedure and treatment protocol**

The first consideration of this study was to select appropriate patients in order to exclude the congenitally influential factor of heterogeneity of CRS. The next consideration was to standardize the preoperative treatment, surgical procedure, and postoperative follow-up protocol. Over the past 10 years, we have developed a standardized surgical procedure and treatment protocol. Preoperatively, the referral doctor administers optimal medical treatment to the patient; if that does not occur, our clinics will administer the treatment. If treatment fails, surgery is suggested. Preoperative medication is not given for at least 2 weeks, if acute exacerbation was not noted before surgery. Some patients are given a loose schedule of intranasal

Other information are also collected during the preoperative visit: age, gender, asthma, nasal polyps, allergic rhinitis, obstructive sleep apnea, diabetes, smoking status, gastroesophageal reflux disease, prior FESS history, and Samter's triad. For the surgical procedure, the objects of FESS include several folds: to clear out the occluded ostium by correcting the anatomical flaw of bottleneck of draining pathway for diseased sinus, to decrease inflammatory load by removing developed polyps or swollen mucosa which was filled with inflammatory milieu, and to clean out entrapped discharge from deep-seated recess which contained inflammationinducing materials. Based on the principles described above, we developed eight

1.Middle turbinate trimming: This procedure is used instead of medial fracture in order to expose the posterior margin of uncinate process and hiatus

2.Uncinectomy: The first step of ethmoidectomy is to properly remove the uncinate process. It can be antegrade, with a sickle knife, or retrograde, by using backbiting forceps, until the superiorly agger nasi cell, and frontal recess

3.Enlargement of the natural ostium of maxillary sinus: By removing the mucosa of posterior fontanelle, the accessory ostium can be identified during this step. Pathologic tissue in the maxillary sinus is removed, and irrigation by normal

and inferiorly the natural ostium of maxillary sinus are identified.

**74**


Postoperative care includes regularly follow-up for at least 6 months using optimal antibiotic treatment, including low-dose macrolide for 2 months and nasal steroids, as well as routine saline nasal douching plus adjuvant of gentamicin for at least 3 months.
