M.D. Tanabaeva, S.A. Taukeleva, Almaty Institute for Advanced Medical Studies, Almaty, Kazakhstan. In recent years, diagnosis of inflammatory diseases of the sphenoid sinus has improved significantly, primarily due to the widespread introduction of computed tomography of the paranasal sinuses into routine ENT practice. Accumulated data in recent years indicate that sphenoiditis is much more common than diagnosed. According to the Otolaryngology Clinic of Kursk Medical University, every fifth patient with sinusitis had sphenoid sinus involvement. (Piskunov S.Z., 2002) Statistical analysis of our data showed that among patients hospitalized in the department with various forms of inflammatory diseases of the paranasal sinuses, sphenoid sinus involvement was detected in every twentieth patient. Acute sphenoiditis typically occurs more frequently during flu epidemics, cold seasons, and off-season periods. Acute sphenoiditis is extremely rare during the hot summer months. The primary and fundamental principle in treating any inflammatory sinusitis is drainage, outflow, and restoration of aeration. Acute and chronic inflammation of the sphenoid sinus are no exception to this principle. The most physiological method for treating sphenoiditis is probing the natural opening of the sphenoid sinus. In routine ENT practice, this procedure is rarely performed due to technical difficulties, difficult access, and lack of visual inspection. All of this requires the highest level of qualification from the physician performing probing and subsequent irrigation of the natural opening of the sphenoid sinus. With the advent of endoscopic technology, visual examination of the natural opening of the sphenoid sinus has become possible, allowing not only improved diagnosis of sphenoiditis but also better identification of its causes. Furthermore, the technique for probing the natural ostium of the sphenoid sinus has been significantly simplified. However, probing alone does not always completely resolve inflammatory sphenoiditis; sinus irrigation and the administration of certain medications are often required to establish drainage and restore aeration. To achieve the desired effect, we have now introduced endoscopic catheterization of the natural ostium of the sphenoid sinus into our daily practice. This procedure is performed with the patient in a supine position. For successful catheterization, we recommend mandatory preliminary anemia and adrenalization of the nasal mucosa, particularly the projection area of ??the middle nasal meatus in the anterior regions. Catheterization is performed under local anesthesia with 10% lidocaine solution. A rigid endoscope with a 30° tube is used for a thorough examination of the nasal cavity using the standard technique. This technique is extremely gentle and minimizes potential damage, while endoscopic visual control allows the procedure to be performed in virtually all anatomical conditions. By introducing endoscopic catheterization of the sphenoid sinus, we are able to treat virtually all cases of acute sphenoiditis without surgical incision. Moreover, this is accomplished in a very short time. Typically, one or two procedures are sufficient. In chronic cases of sphenoiditis, a single procedure immediately alleviates the severity of the condition, including occipital pain, purulent discharge from the nasopharynx, weakness, and malaise. Further treatment and the need for surgical intervention are typically determined on an individual basis.