Diagnostic value of the post-processing technique of multi-slice spiral CT in orbital cyst diseases

To analyze the features of CT imaging of orbital cystic disease.

A total of 30 patients were pathologically confirmed with orbital cystic disease between January 2007 and March 2012. Prior to operation, the participants underwent CT scans with image processing by maximum intensity projection (MIP) and volume rendering (VR). Preoperative CT diagnostic outcomes were compared with postoperative pathological findings.

The patients presented with round, oval and dumbbell shaped masses. Fourteen cases of dermoid cyst and 8 cases of epidermoid cyst showed heterogeneous density. Among the dermoid cyst patients, 6 cases had demixing phenomenon, 3 cases had lipid drift and 5 cases showed mild or moderate intensity enhancement in the cyst wall. No intensity enhancement was observed in the epidermoid cyst patients. Five cases had high intensity due to hemorrhage and 3 patients presented with adjacent sclerotin arc compression; 5 cases of myxoid cyst had homogenous density and no intensity enhancement was found when iohexol was injected. Three patients with atheromatous cyst had heterogeneous density, with CT value ranging from -36Hu to 191Hu. Floss was noted centrally in 1 case and mild to moderate intensity enhancement was observed in the cyst wall with iohexol injection.

Multi-slice CT is useful in the diagnosis of orbital cystic disease. Multi-slice CT combined with image processing can be helpful in displaying the location and size of masses, and revealing the relationship between masses and surrounding boney tissue, providing an objective basis for surgical planning when combined with 3D-CT imaging.