Clinical evaluation of lymphoscintigraphy of the head and neck

Thirty-six patients underwent static and dynamic lymphoscintigraphies with 99m-Tc rhenium colloid in this series. Static lymphoscintigrams were obtained at 3 hours after injection and dynamic lymphoscintigraphy was carried out immediately after injection. 99m-Tc rhenium colloid in each volume of 0.25ml (3.7×10⁷ Bq) was applied by subcutaneous injection into bilateral areas behind the ears for the cervical lymph nodes, and by submucosal injection into the bilateral mucobuccal folds of the upper molar region for the submandibular lymph nodes. Most of the cases demonstrated abnormalities of the lymph node images; (1) asymmetry of lymph node drainage, (2) absence of lymph nodes, (3) reduced uptake, (4) rope-like appearance, (5) enlargement of lymph nodes, and (6) delay of flow rate along the cervical chain. The results of these two imaging techniques correctly predicted the metastatic involvement of cervical lymph nodes from malignant tumors at the rate of about 70%. This imaging technique of lymphoscintigraphy is one of the useful method for evaluating lymph node metastasis, and dynamic scintigraphy especially contributes to more accurate diagnosis of lymph node metastasis.