The Diagnostic Value Of Lingua/pharynx Ratio For Lingual Hypertrophy In Obstructive Sleep Apnea Hypopnea Syndrome

Objective:Lingua/pharynx ratio（L/P ratio）is an effective index to assess the severity of retroglossal cross-sectional area（S）in patients with obstructive sleep apnea hypopnea syndrome（OSAHS）and is used to determine whether or not the lingual hypertrophy exists.However,the diagnostic criterion of the L/P ratio is unknown.Therefore,the purpose of this study is to clarity the diagnostic criteria of the L/P ratio.Methods:193 OSAHS patients were diagnosed by polysomnography（PSG）and accomplished polysomnography after nasopharyngeal tube insertion（NPT-PSG）and CT examination successfully.L/P ratio and S were measured in CT images.According to the NPT-AHI determined by NPT-PSG,all patients were divided into normal group,lingual hypertrophy group and glossocoma group.The AHI,NPT-AHI,S and L/P ratio were compared among three groups.Results:1)The L/P ratio was negatively correlated with S in all patients.2)There is no significant difference in AHI and NPT-AHI between the lingual hypertrophy group and glossocoma group（P>0.05）,and both of them had obvious differences compared with the normal group（P≤0.002）.There was no significant difference in S between the normal group and glossocoma group（P>0.05）,and both of them had obvious differences compared with lingual hypertrophy group（P<0.001）.There was no significant difference in L₁/P₁and L₂/P₂between the normal group and glossocoma group（P>0.05）,and both of them had obvious differences compared with lingual hypertrophy group（P<0.001）.3)For patients with lingual hypertrophy,L₁/P₁was greater than 0.8 or L₂/P₂was greater than 0.82.Conclusion:As the measurement of L₂/P₂was more easier than L₁/P₁.Therefore,we recommended that L₂/P₂could be used as an effective index to assess the severity of lingual hypertrophy.