Differentiation of normal and neoplastic bone tissue in dynamic gadolinium-enhanced magnetic resonance imaging: validation of a semiautomated technique.

PURPOSE: This study was undertaken to clinically validate the accuracy of a semiautomated software tool for analysing the enhancement curve in focal malignant bone lesions. MATERIALS AND METHODS: Twenty-three patients affected by cancer with malignant focal bone lesions underwent dynamic gadolinium-enhanced magnetic resonance (MR) imaging using the following protocol: T1-weighted turbo spin-echo sequences (time to repeat [TR] 600 ms, time to echo [TE] 8.6 ms, field of view [FOV] 40x40 cm) before and after intravenous injection of gadolinium-containing contrast agent. Image postprocessing was performed using the software DyCoH. Each region of interest (5x5 pixels), drawn to include the area of the lesion with the highest values of the area under the curve map, was analysed to obtain time-intensity curves and relative perfusion parameters: time to peak (TTP), peak intensity (PI), slope (60-s slope), intensity at 60 s after contrast agent injection (60-s I) and final intensity (FI). RESULTS: Data were obtained by analysing 86 malignant lesions and 86 apparently normal bone regions. PI, 60-s slope, 60-s I and FI were significantly different between neoplastic and apparently normal (p<0.001) samples. Sensitivity, specificity and accuracy were, respectively, 94%, 93% and 94% at a PI threshold of 100 (signal-to-noise ratio), with positive and negative predictive values of 93% and 94%. At a threshold value of 0.85 for 60-s slope, sensitivity and specificity values were both 91%. CONCLUSIONS: The semiautomated technique we report appears to be accurate for identifying neoplastic tissue and for mapping perfusion parameters, with the added value of a consistent measurement of perfusion parameters on colour-coded maps.

Incidence of new fractures in women with osteoporosis-induced vertebral fractures detected on routine lateral chest radiographs.

PURPOSE: Vertebral fractures represent one of the major complications of osteopororis. Diagnosis is followed by a pharmacological, interventional or surgical treatment. Up to day there are non practice guidelines for a screening evaluation of bone fractures in elderly and most of the fractures remain undiagnosed. We prospectively evaluated the prevalence of vertebral fractures on chest X-rays to determine the diagnostic and prognostic roles of chest X-ray in predicting new bone fractures 2 years after the initial radiogram. MATERIALS AND METHODS: Between March 2004 and October 2005, 4,045 women underwent chest X-ray in our radiology department for any indication. We identified 166 women with the presence of at least one vertebral fracture. A questionnaire was administered to these women to collect information about diagnosis of osteoporosis, history of malignancy, systemic diseases, osteoporosis-inducing drugs and pharmacological, radiological or surgical treatment received. RESULTS: Out of the 166 women (age 73+/-10.5 years) with vertebral fractures, we interviewed 101 women; 13 had died and 52 were not found. Most of the patients were on menopause (97.1%, 98/101) with an average age of menopause of 48,2 years (+/-6 years). Among the patients on menopause, 15,8% (16/101) had undergone hysterectomy. All patients received a diagnosis of osteoporosis, which was reached with a chest X-ray report in 23.7% (24/101) of cases. A new skeletal fracture occurred in 20.5% (5/27) of patients receiving treatment against a frequency of 20.8% (16/74) in patients without treatment. No statistical difference was found between the groups (p = 0.374). CONCLUSIONS: Inadequate treatment may explain the lack of a substantial difference in new fracture risk between treated and untreated patients. For these reason we discuss about the evaluation of an adeguate therapeutic approaches in prevention of osteoporosis-induced fractures.