Differentiating benign and malignant salivary gland tumours: diagnostic criteria and the accuracy of dynamic contrast-enhanced MRI with high temporal resolution.

OBJECTIVE: To determine the optimal diagnostic criterion of dynamic contrast-enhanced MRI (DCE-MRI) for predicting salivary gland malignancy using a dynamic sequence with high temporal resolution, as well as the accuracy of this technique. METHODS: The DCE-MRI findings of 98 salivary gland tumours (74 benign and 24 malignant) were reviewed. MR images were sequentially obtained at 5-s intervals for 370 s. Two parameters, peak time and washout ratio (WR) were determined from the time-signal intensity curve. The optimal thresholds of these parameters for differentiating benign and malignant tumours were determined, along with the diagnostic accuracy of the criterion using these thresholds. RESULTS: A peak time of 150 s and a WR of 30% were identified as optimal thresholds. As the criterion for malignancy, the combination of peak time <150 s and WR <30% provided a sensitivity of 79% (19/24), specificity of 95% (70/74) and an overall accuracy of 91% (89/98). Three of the five false-negative cases were malignant lymphomas of the parotid gland. CONCLUSION: Peak time <150 s with WR <30% comprised the optimal diagnostic criterion in predicting salivary gland malignancy, providing a sensitivity of 79% and specificity of 95%. The use of high temporal resolution might improve the accuracy of DCE-MRI. ADVANCES IN KNOWLEDGE: Although several studies have reported the usefulness of DCE-MRI in the differential diagnosis of salivary gland tumours, the specific diagnostic criteria employed have differed widely. We determined the optimal criterion and its accuracy using a dynamic sequence with high temporal resolution.

Space-occupying lesions in the right ventricle of a patient with antiphospholipid syndrome.

A 29-year-old woman presented with shortness of breath, vague chest pain, and prominent intermittent ejection systolic murmur. Transthoracic echocardiography showed a large mass in the right ventricular outflow tract. Transesophageal echocardiography demonstrated two masses that were adherent to the tricuspid valve and intermittently prolapsed through the pulmonary valve. Computed tomography of the chest corroborated the echocardiographic findings. Currently, there are no definitive guidelines regarding the optimal management of right heart thrombi in patients with antiphospholipid syndrome. Our patient did not respond to a standard dose of rt-PA used in the treatment of pulmonary embolus. She underwent successful surgical resection of the thrombi without complications.