Endoscopic middle meatal approach is one of the most commonly performed functional ESS procedures. The nasal cavity is decongested using a gauze with lidocaine and epinephrine. The lidocaine with epinephrine is injected at the level of the middle turbinate root and uncinate process. The uncinate process is removed in case of middle meatal antrostomy. Complete removal of fungal debris by ESS through an uncinectomy and a sufficiently wide meatal antrostomy is performed. The large or wide antrostomy means that we have a good visualization of the maxillary sinus and surgical instruments can be inserted easily. There are varying opinions on what the size of the antrostomy should be. If the ethmoid bulla is severely blocked, the ethmoidectomy has to be performed. After widening of the antrostomy for the maxillary sinus, the fungal ball is extracted using curved suctions, forceps, and curved microdebrider blades.

The “Gauze technique” is a simple and quick method used to be removed the fungal ball in the maxillary sinus [5] . It is a standard ESS using traditional instruments with the gauze. The surgical procedure is following the steps. After making a wide antrostomy, the fungus ball is removed with the curved endoscopic pincers and suction. The gaze soaked in a standard saline solution is introduced into the maxillary sinus through the antrostomy. The bulk of the gauze pushes out the remaining fungal debris using a curved suction or curved pincers, and then a gauze can be used to push the fugal ball out of the antrostomy. The same procedure is repeated several times, after which the gaze can be easily removed with curved forceps from the antrostomy.

When fugal debris can be removed completely, it is not necessary to have a large opening in the middle meatus for sufficient access to the maxillary sinus cavity. Although the mucosa should be preserved, it must be biopsied to exclude any possibility of microscopic invasion by fungi. Infected granulation tissue should be removed using curved forceps and microdebrider blades, but the periosteum of the sinus must be preserved in such cases. When the fungal ball is located near the ostiomeatal complex, it is a good indication for a middle meat us approach (Figure 1).

It is impractical to make a new window at the inferior meatus for these cases. On the other hand, it is sometimes difficult to see the anterior inferior or medial inferior wall of the maxillary sinus even when a 70˚ endoscope is used, when the maxillary sinus is observed from a middle meatus window. The insufficient visualization of the entire maxillary sinus means that removal of the fungal ball will be incomplete. Thus, it is possible that fungal debris removal will be incomplete from a middle meatus window, and only when the fungus ball is not located in the anterior inferior and medial inferior wall of the maxillary sinus, will complete removal be achieved.

Our department recently published a study that combined both middle and inferior meatal antrostomy. This combination was shown to be effective for the treatment of FRS [6] . Our study showed that the results of ESS with the combined approach were better than the middle meatal approach alone without inferior meatal antrostomy [6] . The post-operative CT examination at 3 to 4 months after the ESS, showed a normal maxillary sinus, and no cases of recurrence were observed in combined approach group in our study (Figure 2) [6] . Klossek et al described that the middle meatus antrostomy had to be associated with an inferior antrostomy in about 65% of the cases in order to facilitate access

and removal of the fungal ball [7] . Dufour et al. reported 150 fungus ball maxillary sinusitis cases that revived the ESS procedure [8] . They performed middle meatus antrostomy (n = 53/150, 35%) and a combination of middle and inferior antrostomy (n = 97/150, 65%) [8] . Based on these reports, the combination of middle and inferior antrostomy appeared to be required in over 60% of fungus ball maxillary sinusitis ESS procedures. The double ventilation pathway operation is superior to the single ventilation pathway. The combined approach makes it easier to observe the whole sinus, especially the anterior inferior and medial inferior wall of the maxillary sinus, compared with the single middle meatus approach. As for the post-operative micociliary function of the maxillary sinus, the previous report suggested that a combination of middle and inferior meatal antrostomy does not disturb the microciliary clearance [9] . Our previous study showed that a combination of the middle and inferior meatus antrostomy approaches did not disturb the post-operative nasal condition [6] . We performed the combined approach of ESS in the following steps. First, the uncinate process was removed for a sufficiently wide meatal antrostomy (see 2-1. Middle meatus approach). The surgeon decided whether or not to perform an inferior meatal antrostomy based on the observation of the maxillary sinus which was observed from the middle meatal window. When the fungal ball was located on the anterior or inferior side of the maxillary sinus, or if the surgeon could not see that area, an inferior meatal antrostomy was performed. In this approach, the bridge of bone between the two antrostomy preserved the inferior turbinate. The inferior turbinate is fractured medially, allowing space for the endoscope (0 or 30 degree) prior to make an inferior meatal antrostomy being made.

Even if the inferior meatal antrostomy is closed after the surgery, which is not a major problem, we usually perform the meatal mucosal flap procedure to avoid closure or stenosis of the inferior meatal antrostomy (Figure 3). Tani et al. reported that the inferior meatal antrostomy opening ratio was 89% for the inferior

meatal mucosal flap procedure after ESS [10] . The U shaped meatal flap was elevated on the inferior and lateral mucosa in the inferior meatus. After elevation from the meatal bone, the flap was positioned on the nasal floor (Figure 3(a)). Then an inferior meatal window was created using a perforator, or chisel. The bony wall was removed piece-by-piece to make a sufficient opening in the maxillary sinus. When the maxillary bone is hard, and it is difficult to make a hole, it is better to use an angled drill. After making an opening that was sufficiently wide, the mucosal flap was positioned across the inferior lip of the bony window into the maxillary sinus (Figure 3(b)). We can easily observe the inside of maxillary sinus and insert surgical instruments through the inferior window or middle meatus.

To remove the fungal ball, a gauze which has a size of either 3 cm × 15 cm or 3 cm × 30 cm is generally used. The gauze is soaked with normal saline or saline which includes epinephrine. The gauze is introduced into the maxillary sinus from the inferior meatal window using curved forceps (Figure 4(a)). Several gauzes are pushed into the maxillary sinus (Figure 4(b)), and then a gauze can be used to push the fugal ball out of the middle meatus (Figure 4(c)). The gauze can then be removed from the middle meatus or inferior meatal window. The same procedure is repeated until fungal ball can be completely removed (Figure 4(d)).

Okanoue et al. described the combined approach using a Foley catheter instead of the gauze-assisted technique [11] . They insert the catheter into the maxillary sinus from the inferior meatal antrostomy. The inflated balloon (10 ml) causes fungal debris to extrude into the nasal cavity through the middle meatal antrostomy. Debris may remain on inferior or posterior wall of the maxillary sinus, which can then be removed by curved suction, forceps or curved microdebrider blades. This is easy and effective way to remove a fungal ball.

Endoscopic medial maxillectomy with medial sift of preserved inferior turbinate

is a procedure for FRS that was introduced in 2008 (Japanese article) [12] . It was described that the head of the inferior turbinate is cut once using turbinate scissors up to the middle meatal antrostomy. This was done so that there is sufficient visualization of the sinus from the inferior meatus. After sifting the preserved inferior turbinate to the posterior midline position, the medial maxillectomy is performed from the middle meatal antrostomy using the backbiter cutting forceps. After the removal of fungal ball, the turbinate is repositioned and sutured with the anterior mucosa in its original position. This method was effective and has been widely accepted in Japan because it utilizes a relatively easy technique with a straight endoscope and instruments from to the inferior meatus. It is similar to the previously reported endoscopic medial maxillectomy with preservation of the inferior turbinate [13] [14] . These approaches are managed through the posterior side of the nasolacrimal duct. Therefore, it is difficult to obtain good visualization of the fungal ball located in the area between the nasolacrimal duct and anterior wall of the maxillary sinus (Figure 5(a)). In such a difficult case, endoscopic modified medial maxillectomy (EMMM) is the preferred choice (Figure 5(b)) [15] . Tsuta et al. first described this effective procedure for chronic sinusitis showing a transnasal endoscopic medial maxillectomy with preserved inferior turbinate and nasolacrimal duct in 1993 (Figure 6)

[16] . A vertical incision is made in the mucosa of the lateral wall along the anterior margin of the inferior turbinate to the nasal floor (Figure 6(a)). The lateral nasal mucosa is separated from the medial maxillary wall bone (Figure 6(b)). They described that this procedure is initiated by an incision similar to the one used for submucosal resection of the inferior turbinate. After resection of the bone of the inferior turbinate, osteotomy of the medial maxillary bone is performed. At this time, the bone around the nasolacrimal duct is removed gently, and then the nasolacrimal duct is free from the bone (Figure 6(c)). The preserved inferior turbinate mucosa and the nasolacrimal duct can be swung from side to side. The authors called these steps of the procedure “the swing method.” After the removal of fungal debris, the turbinate is repositioned and sutured with the anterior mucosa in its original position (Figure 6(d)). This procedure is similar to the modified transnasal endoscopic medial maxillectomy for inverted papilloma published in 2011 [17] . When it is necessary to obtain improved access to the maxillary sinus, osteotomy of the anterior wall of the maxillary sinus can be added. These approaches have become widely accepted and recognized as EMMM (we call it EM-three) for FRS.