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

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.

The "Raven Sign": A case of apical left lung herniation into the superior right hemithorax detected on 99mTc-MAA lung perfusion scintigraphy in a pediatric patient with pulmonary tuberculosis

Lung hernia is a rare finding described as the protrusion of lung tissue outside the pleural cavity. Lung perfusion scintigraphy is used for pre-operative assessment of high-risk patients prior to pneumonectomy This case report presents a case of an apical left lung hernia detected in a lung perfusion scan prior to elective pneumonectomy in a seven-year-old girl with pulmonary tuberculosis destroyed right lung and compensatory left lung hyperinflation.

Therapy dose calculation in Graves disease using 4-hour I-131 uptake measurements: A retrospective study

Twenty-four-hour radioactive iodine uptake (RAIU) is commonly used to compute for therapy dose in Graves disease (GD). The purpose of this study is to determine the feasibility of using 4-hour RAIU in calculating the dose by correlating 4-hour with 24-hour RAIU and comparing the actual therapy dose using 24-hour RAIU with the computed dose using 4-hour RAIU. A total of 83 GD patients (71% female, 29% male;18-50 years old), who underwent RAI therapy at USTH Section of Nuclear Medicine, were included. There was a strong and positive correlation between 4-hour and 24-hour RAIU values (r=0.736). Paired t-test did not show a statistical difference between the actual given therapy dose based on 24-hour RAIU and the computed therapy dose using 4-hour RAIU (p 0.078). This study showed that therapy dose calculation using 4-hour RAIU can be used in Graves disease patients with no rapid turnover.