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.