Clinical Application of 64-detector CT as Middle-ear Virtual Endoscipy and Three-dimensional Reconstruction of Ossicular Chain

Objective To assess the application of 64-detector CT for the virtual endoscopy(VE) ,the reconstruction of ossicular chain and the oblique reconstruction of stapes. Methods 33 patients were examined by GE Lightspeed 64-detector CT. The 66 ears include 31 chronic suppurative otitis media. All lesions were confirmed by clinical examination and operation. The data was transferred to a workstation via an internal Dicom network for post-processing. CTVE, SSD of ossicular chain and the oblique reconstruction of stapes were processed on 66 ears. CTVE, SSD of ossicular chain and the oblique reconstruction of stapes of normal ears were compared with anatomy and coronal and axial CT film, and that of ill ears were compared with operation and coronal and axial CT film. Results The representation of the structures of ill ears on CTVE and its comparison with coronal and axial CT film and operation: In 24 purulent otitis media, CTVE had a coincidence of 91.7% with operation of handle of malleus, 95.8% of head of malleus,95.8% of long limb of incus ,100% of short limb of incus, 87.5% of limbs of stapes. There were no significant differences between the rate of coincidence of CTVE and that of coronal and axial CT film, but CTVE、 SSD and the oblique reconstruction of stapes had a higher coincidence (average 93.3%、95%、91.7%) than coronal and axial CT film (average 90%). Conclusion CTVE, SSD of ossicular chain and the oblique reconstruction of stapes can wholely show the ossicular chain, and have a high coincidence of the destruction of ossicular chain. The imaging of CTVE, SSD of ossicular chain and reconstruction of stapes of 64-detector CT is clear and tridimensional with a short time, and can be applied in clinical examination.