Comparison of bone scintigraphy with single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) in the detection of sphenoid bone extension from nasopharyngeal carcinoma (NPCA): A retrospective study

ABSTRACT

BACKGROUND/OBJECTIVE: Skeletal metastasis is one of the major clinical problems in managing cases of NPCA. Beginning osseous metastasis in the form of sphenoid bone extension is commonly seen in NPCA.Imaging modalities mainly used in detecting sphenoid bone extension are bone scintigraphy with SPECT and MRI. In this paper, the ability of bone scintigraphy with SPECT and MRI in detecting sphenoid bone extension was compared.MATERIALS AND METHODS: Twelve patients with nasopharyngeal carcinoma were studied by bone scintigraphy with SPECT and MRI. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of each modality against the gold standard, which is sphenoid bone biopsy, were computed. Statistical analysis was done using the McNemar's Test.RESULTS: The overall performances of bone scintigraphy with SPECT versus MRI were the following: sensitivity 89% vs 78%, specificity 33% vs 67%, positive predictive value 80% vs 88% and negative predictive value 50% vs 50%. There was no significant difference between the two modalities using McNemar's test (p>0.05).CONCLUSION: Bone scintigraphy with SPECT and MRI were both equally effective and were complementary with each other in detecting sphenoid bone extension in patients with NPCA.