V. A. Obodov, E. S. Borzenkova, M. I. Shlyakhtov (Ekaterinburg Center of Scientific and Technical Complex "Microsurgery of the Eye", Director - O. V. Shilovskikh) Abstract. The work presents the long-term results of treating 20 patients with an advanced stage of lacrimal sac phlegmon using endoscopic endonasal surgical dacryorrhinocystostomy. The results were evaluated 6 months or more after the surgery. Complete recovery with restoration of lacrimal drainage into the nasal cavity was achieved in all patients. In recent years, due to the development of new technologies, endosurgical treatment has become the method of choice for treating lacrimal sac phlegmon. This method allows for emergency and minimally invasive elimination of not only phlegmonous inflammation of the lacrimal sac, but also general sanitization of the lacrimal ducts until complete recovery [1, 2]. Objective. Evaluation of the long-term results of endosurgical treatment of lacrimal sac phlegmon. Materials and methods. The long-term treatment outcomes of 20 patients with advanced lacrimal sac phlegmon treated with endoscopic endonasal surgical dacryocystorhinostomy in 2005 were analyzed. Of these, 16 were women and 4 were men, aged 19 to 77 years. The total disease duration ranged from 6 months to 10 years or more. By etiology: chronic dacryocystitis was observed in 17 patients, post-traumatic dacryocystitis - in 3. All patients at the time of presentation to our clinic had undergone prior treatment: conservative - in 4 cases, spontaneous opening of the lacrimal sac - in 6 (repeated - in 3), surgical external drainage without the formation of rhinostomy - in 9 (including multiple - in 4, with the formation of a fistula of the lacrimal sac - in 2), external dacryocystorhinostomy - in 1. In addition to the standard ophthalmological examination, all patients underwent endoscopic rhinoscopy before surgery to determine the condition of the nasal cavity and the possibility of endoscopic surgical intervention. Normal nasal anatomy was detected in only three patients. The remaining cases had abnormal nasal structures or pathological changes (or a combination of both), including a raised nasal septum, narrow nasal passages, an enlarged uncinate process, signs of chronic rhinitis, nasal mucosal polyposis, and traumatic lacrimal sac dislocation. All patients presented with uncontrast-enhanced CT scans of the orbits and paranasal sinuses in three projections; however, lacrimal sac enlargement on the affected side was noticeable. Prior to surgery, patients were prescribed antibiotic therapy: 0.5 g of cifran orally twice daily and 5 times daily of ciprolet epibulbarly. The treatment was performed endoscopically, endonasally, under general anesthesia, on an outpatient basis, regardless of the severity of changes in the skin and subcutaneous tissues in the projection of the lacrimal sac, using the technique described in the Color Atlas of Lacrimal Surgery (edited by Jane Olver, 2002). We did not perform local treatment or external drainage. Elimination of the lacrimal sac fistula (in 2 patients) was not performed surgically. The operation was completed by intubation of the lacrimal ducts with the Monoka silicone system through one of the lacrimal canaliculi with the outlet and fixation of its free ends on the ala of the nose - in 13 cases, with the Bika system through both lacrimal canaliculi with fixation in the nasal cavity - in 5 cases. In 3 cases, the operation was performed without intubation of the lacrimal ducts. Removal of the silicone systems was performed 1 month after the operation. Results and discussion. The outcome was assessed 6 months or more after the surgery. Complete recovery with restoration of tear drainage into the nasal cavity was achieved in all patients. The resulting rhinostomy was wide and well-functioning. Inflammatory processes on the skin over the lacrimal sac and infraorbital region resolved within the first 3 days after surgery without additional local treatment. No residual changes were observed in this area. Lacrimal sac fistulas healed spontaneously 1 week after surgery. In one case of traumatic dacryocystitis, a relapse occurred 3 months after surgery due to significant dislocation and dilation of the lacrimal sac. A repeat operation, taking these factors into account, resulted in complete recovery. Thus, endoscopic endonasal dacryocystorhinostomy is highly effective and should be the treatment of choice for lacrimal sac phlegmon at any stage. Endosurgical treatment of lacrimal sac phlegmon does not require additional local treatment of infraorbital tissue inflammation or surgical closure of fistulas. Long-Term Results of Treatment of Dacryocyst Phlegmons V. A. Obodov, E. S. Borzenkova, M. I. Shlyahtov (IRTC Eye Microsurgery Center Ekaterinburg) In this study, long-term results of treatment of 20 patients with the educated stage of a dacryocyst phlegmon were obtained using an endoscopic surgical method. The results were assessed at 6 or more months after surgery. Full convalescence with regeneration of the lacrimal outflow in a nasal sinus was achieved in all patients. References Cherkunov B. F. Diseases of the lacrimal organs. Samara, 2001. pp. 191–215. Malinovsky G. F., Motorny V. V. Practical treatment of diseases of the lacrimal organs. Minsk, 2000. pp. 164–167.