We thank Dr Kamal for his comments on our article and wish to clarify his concerns regarding our study.
First, topical antibiotics were included in the postoperative antibiotics regimen, and topical quinolones were used for 1 week. In endonasal dacryocystorhinostomy (DCR) cases, nasal steroids were also used for 2 to 3 weeks. Because it has been reported that prophylactic antibiotics are helpful in terms of surgical outcomes, broad-spectrum antibiotics were used in all patients for 1 week after surgery, and it does not seem inappropriate that we used third-generation cephalosporins, which prophylactically can cover both gram-positive and gram-negative bacteria uniformly in all patients where infection is not established. Also, because the silicone tubes generally were removed a few months after insertion, the use of prophylactic antibiotics or the nasal steroid is believed to have had little effect on the results of this study.
Second, the 8 patients who were reported to have discharge showed the discharge only at the time of tube removal, not during the entire period during which the silicone tube was in use. When an infection was suspected, we did not wait, but immediately removed the tube and treated our patients with proper antibiotics. Although the range of the extubation period was from 0.8 to 40 months, in most of the patients, the tube was removed within 6 months (28/39; 71.8%) and was maintained for more than 9 months in only 4 patients. The 2 patients had their tubes removed at 40 and 20 months, respectively, because they were lost to follow-up without any complications. They visited the hospital for recently developed discharges, and their tubes immediately were removed during the examination. The other 2 patients whose intubation period was more than 9 months had preoperative canalicular stenosis, which was not yet resolved after distal canaliculotomy. So, we thought that maintenance of the silicone tube would be helpful to raise the patency rate. Of course, however, if discharge developed, we removed the tube immediately and treated the patient with proper antibiotics. Currently, because maintaining the silicone tube for a longer period does not have a positive effect on the success rate of the procedure, as the author pointed out, the tube is removed within 2 to 3 months if the fluorescein dye passage is observed at the nasal ostium with an endoscope.
This study does not indicate that we have achieved successful clinical outcomes through adequate extubation after DCR, nor does it support the late removal of the silicone tube. The point of our study is that in cases of less successful surgery or of longer intubation period, pseudomonal infection may occur, which may influence surgical outcomes, and that in these cases, early removal of the tube coupled with culture studies is recommended, using proper antibiotics in case where cultures reveal pseudomonal infections.
Third, as stated before, appropriate antibiotics were used in all 3 patients who had their tubes removed for symptoms of discharges and showed pseudomonal infection in cultures. Because the results of the sensitivity test showed that Pseudomonas aeruginosa was sensitive to ceftazidime, amikacin, and ciprofloxacin, we used topical quinolone and systemic third-generation cephalosporin. Although pus discharge decreased with treatment, continued epiphora was observed, signifying surgical failure. Because sensitivity tests were not conducted for all strains, it was mentioned as a limitation of this study in the discussion; however, with regard to pseudomonas and discharge, we confirmed sensitivity results and applied adequate treatment.
Fourth, previous culture reports present results of chronic dacryocystitis patients with purulent discharges, which were cultured from purulent material or lacrimal sac biopsies at surgery. However, our study deals with postoperative bacteriology in DCR patients with epiphora resulting from lacrimal obstruction. Therefore, this study is basically different from previous reports in terms of patient group and the time of bacterial identification. Also, it should be noted that chronic dacryocystitis does not occur in all patients with nasolacrimal duct obstruction and that in those studies, the relationship between the cultured flora and surgical outcome was not studied. Thus, we disagree with the dismissal of the results of our report on the basis that the patterns of bacterial strains are the same.
Finally, we used mitomycin C only in revisions, not initially. It has not been confirmed whether the use of mitomycin C increases the success rate of DCR in patients with canalicular obstruction, and the focus of this study is neither on mitomycin C nor on how to increase the success rate of surgery for canalicular obstruction. Although infections can be affected for immunocompromised patients, none of our patients were diagnosed with HIV or any form of malignancy. Five patients were diagnosed with diabetes, but the disease was not related to surgical failure or pseudomonal growth.