Sonographic Diagnosis of Metastatic Cervical Lymph Nodes in Primary Orofacial Malignancies: Role of the Radiologist's Experience.

BACKGROUND There is uncertainty surrounding the choice of a better imaging modality to detect metastases in cervical lymph nodes. The aim of this study is to examine the role of Ultrasound in the diagnosis of metastatic cervical lymph nodes in orofacial malignancies in a resource limited environment and the effect of the radiologist's experience in interpretation of the results. METHODS Sixty patients with various histologically diagnosed orofacial malignancies and clinical evidence of cervical lymph nodes metastases were examined with ultrasound by a consultant and a trainee radiologist. Affected lymph nodes were subsequently biopsied and examined histologically. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were calculated. Data were analyzed using Statistical Package for Social Sciences (SPSS) version 19 (SPSS Inc., Chicago, IL, USA) and Microsoft Excel 2010 (Microsoft, Redmond, WA, USA). Test of statistical significance was set at 0.05. RESULTS Ultrasonography examination by the consultant radiologist recorded a sensitivity of 80.0%, specificity of 57.1%, PPV of 77.5%, NPV of 60.0%, accuracy of 71.7% and a P value of 0.004. The trainee radiologist recorded a sensitivity of 69.2%, specificity 38.1%, PPV of 67.5%, NPV of 40.0%, accuracy of 58.3% and a P value of 0.566. CONCLUSION Ultrasonography is useful in the diagnosis of metastatic cervical lymph nodes in orofacial malignancies and the interpretation and reliability of the results depend on the experience of the radiologist. Examination of patients should therefore be done and interpreted by an experienced radiologist.