The Stethoscope–Tuning Fork (ST) Test, or Ahmadizadeh Test, for the diagnosis of sinusitis was first introduced in 1987.1 It is based on physical property of sound, which is heard louder through solid materials. A vibrating tuning fork (256 or 512 Hz) is placed in the middle of the patient's forehead while the examiner listens intermittently to the tone over the antra with a stethoscope (Figure 1 and Figure 2). The vibration will be louder over the side where more density is present. The test result is considered positive when asymmetrical sound transmission is present. The positive ST test result, along with clinical findings, will help the examiner to diagnose the presence of sinus abnormalities.
Ahmadizadeh A. Stethoscope–Tuning Fork Test (Ahmadizadeh Test) for Diagnosis of Sinusitis. Arch Otolaryngol Head Neck Surg. 2001;127(10):1288. doi: