Main outcome measures
Burghart Sniffin’ Sticks®, a widely assessment test for smell disorders8, was used to assess the olfactory function in the study participants. Four values, threshold (T), discrimination (D), identification (I) and the TDI values were measured before treatment and 1 month later. A TDI value below 16.75 points represents functional anosmia. Also TDI value between 16.75 and 30.50 points represents hyposmia and TDI value of 30.75 points or more represents normosmia. The patient is considered to be improved when the TDI value has increased by 6 points
Participants’ nasal secretion was collected before treatment and 1 month later. Collection occurred immediately after sneezing. A stainless steel (approximately 10 mm × 5 mm × 2 mm) was clamped on the septum between the nostrils to allow the mucus to drain into a special 1.5-mL tube9. The collected secretion was transferred to centrifugation tubes after adding 0.5 mL of borate buffer solution. The protein content of the mucus was denatured by adding 3 mL borate buffer solution. The collected tubes were centrifuged at 4000 rpm for 30 minutes. The protein-free supernatant was evaporated and the residues obtained were dissolved in 10 mL of borate buffer solution. The carbon paste ion-selective electrode 10 was prepared by (blinded for review). It was designed to quantitatively analyze the calcium cation concentration of the collected nasal secretions of the participants before treatment and 1 month later.