Materials & Methods: Total of 45 volunteers aged 18-65 years were included in this study. The degree of overlap in percentage, depth of IJV from skin, antero-posterior (AP) and transverse diameters (TD) of IJV were measured in real time with ultrasound (US). Measurements were taken in the HA, CA and MA in neutral and 30° head rotation on both the right and left side of the neck.
Results: The HA had lower percentage of overlap when compared to CA and MA in neutral and 30° head rotation (p= 0.002 to ≤0.001). The IJV was more shallow in the CA and MA. The AP and TD of the IJV were larger in the MA when compared to HA (p=<0.001) and CA (p =0.026 to < 0.001) and the right IJV has a larger AP and TD in all approaches.
Discussion: The HA had the least percentage of overlap compared to CA and MA, therefore the risk of accidental ICA puncture can be reduced. The apparent overlap seen in MA may not reflect the actual scenario because of the way the US beam cuts the vessel. The AP and TD of IJV were significantly increased in the MA, which would ease CVC.
Conclusion: We conclude and recommend the medial oblique probe position with 30° head rotation provides optimal real time sonographic parameters for US guided IJV cannulation.
Methods: 383 snores from 40 participants who complained of snoring were digitally recorded during natural and induced sleep using a level III polysomnography monitor with a built-in microphone. During drug-induced sleep endoscopy (DISE), the real-time site of upper airway obstruction was assessed, and the sound frequency of snoring was recorded synchronously.
Results: The mean peak of snoring frequency for unilevel palatal, oropharynx and epiglottis obstruction were 522.5, 482.4 and 300.0 Hz, respectively. Most participants showed multilevel obstruction at the palate and oropharynx, in which the mean for bi-peak snoring frequency were 402.90 Hz and 1086.96 Hz, respectively. Severity of OSA was significantly associated with multilevel obstruction.
Conclusions: There was a significant association between the snoring sound frequency and site of unilevel obstruction. Palatal or oropharyngeal obstruction produced sound at mid-frequency range, while the epiglottis produced a low frequency range. Multilevel obstruction documented a bi-peak snoring frequency.