Abstract:Objective: To explore the clinical value of CT manifestation and methods of measurement of adenoid vegetation in children. Materials and Methods: Nasopharyngeal CT plain scans and dynamic CINE CT scan were obtained in 50 children aged 9 months to 14 years with operation proved adenoid hypertrophy as study group and 50 age and gender matched children without adenoid hypertrophy as control. Measurement of maximum thickness of adenoid/anterior-posterior diameter of nasopharyngeal air space ratio(A/N ratio), effective anterior-posterior diameter of nasopharyngeal air space(D value), effective sectional areas of nasopharyngeal air space(Sn) and difference of Sn on dynamic CINE CT(△S) were carried out at the level of sphenoccipital junction on midline sagittal plane. Results: On the transverse CT, hypertrophy adenoid manifested as soft tissue mass that was symmetric, unilateral or embedded into choana. Measurements of study group were: A/N ratio ranged from 0.61 to 0.86, D ranged from 1 to 2.8mm, Sn ranged from 0 to 97.86mm2 and △S ranged from 0 to 32.54mm2. The correspondent measurements of control group were 0.34~0.61, 7.5~12.2mm, 217.87~623.98mm2 and 175.87~274.02mm2 respectively. Conclusion: CT is much better than the lateral X-ray plain film measurement of nasopharynx in the diagnosis of adenoid vegetation for CT can provide much more information and can clearly depict the nasopharynx and CT CINE is especially useful to reflect the changes of nasopharynx with respiration. A/N ratio and D value can be used as indicators: pathologic adenoid hypertrophy should be considered when there is an A/N ratio greater than 0.71 and a D value less than 3mm.