Figure 3
Plan of Three Dimensional-Conformal Radiation-Therapy. (a, b, c): The distribution of target region, the target region includes the primary malignancy, pharyngeal lymphoid ring and upper cervical lymph node region; (d, e, f): The distribution of isodose curve, the total tissue dose is 70Gy/35f. The 95% isodose curve covered the planning target volume; (g), The dose-volume histogram showed that the radiation doses received by the surrounding normal tissues, which include brain stem, spinalcord and lens, are all lower than the safe dose threshold.