Nghiên cứu đặc điểm hình ảnh và giá trị của cắt lớp vi tính 64 dãy trong chẩn đoán u tuyến thượng thận

Study of imaging characteristic and value of 64-slice CT in diagnosis of Adrenal tumor

SUMMARY:

Objective: This study aims to describe the characteristic and value of diagnostic adrenal tumor on 64-slice CT scanner

Materials and Methods: Prospective and cross-sectional descriptive study of 39 patients were diagnosed adrenal tumor on 64-slice CT scanner. The receiver operating characteristic (ROC) curves for the value of size, the attenuation values at the unenhanced CT and the relative percentage washout (RPW) and absolute percentage washout (APW) values for the differential diagnosis of adenoma from nonadenoma.

Results: Adrenal tumor was common as adenoma (16/38) with the feature of often homogeneous, clearly limited and small size (2.5 cm), and about 11.5 HU on precontrast attenuation. Pheocromocytoma was often heterogeneous, large size of 4.76cm and in conjunction with high levels of dynamic enhancement (108.3 Hu and 111.7 Hu). Tumor adrenal malignant was large size of 8.83cm, often unknown limits, infiltrates surrounding and invading IVC (2/3 cases). The area under the ROC curve and cut off with size were 0.896 and 3.29 cm, the attenuation values at the unenhanced CT were 0.984 and 24 Hu, APW were 0.937 and 57.6% and RPW were 0.994 and 43.7% (p <0.001). The sensitivity, specificity and accuracy at the threshold size of 3.29 cm were 88.2%, 90.9% and 89.7%, respectively; at threshold 24 Hu were 94.1%, 95% and 94.6%; at threshold APW = 57.6% and RPW = 43.7% were 94.1%, 85%, 89.2% and 94.1%, 100%, 97.3%, respectively.

Conclusion: 64-slice CT scanner is effective methods to characterize and diagnose adrenal tumor. The relative percentage washout (RPW), absolute percentage washout (APW), the attenuation values at the unenhanced CT and the size criteria appear optimal for discriminating an adrenal adenoma from a nonadenoma.

Keywords: Adrenal Gland Neoplasms, Adrenal Glands, radiography.