The Comparative Study of Spiral CT and Operation in Congenital Malformation of the External and Middle Ear

Objective To improve the level of CT and reconstruction technique in diagnosis of congenital malformations in the external and middle ear. Materials and Methods 22 cases (24 ears) of deformity in the external and middle ear were performed with high differentiate scan in dual slice spiral CT and all the data were reconstructed by multiplanar reformation (MPR),curved multiplanar reformation(cMPR) and volume reconstruction (VR).The comparion of CT findings and operation was made in details. Results In 24 ears,external auditory canal stenosis was found in one ear,bony atresia in 18 ears and membranous atresia in 3 ears. The cavitas tympanica became narrow in 12 ears.The malleus was deformed or Absent in 23 ears,while tiny malleus found in one ear on CT pictures was Absent in operation. There were no incus in 4 ears and malformation in 16 ears. The body was enlarged and the long crus of incus was a little longer than normal in operation but the findings on CT were roughly normal in 2 ears. Small stapes was showed in 6 ears,other abnormity in 7 ears and deficiency in 5 ears. Fusion of incudomalleolar joint was in 14 ears,lightly disfiguration in one ear and Absence in 4 ears. Fusion of incudostapedial joint was in 1 ears,while disconnection in 5 ears and deficiency in 7 ears. Oval window was bony atresia in 8 ears,all the above findings were agree with operation. Round windows of 3 ears were bony atresia on operation,of which one ear was normal on the CT images. There was no the gap of pharyngotympanic tube in 3 ears on operation,of which one ear was co mmon on CT pictures while the anteposition of facial canal was in 8 ears,of while no abnormality in one ear on CT images. Conclusion The congenital malformations in the external and middle ear can mainly reflect through spiral CT high differentiate scan and multiple reconstruction and CT is advantage to the guides of surgical operation.