An assessment of the effectiveness of magnetic resonance imaging in delayed sequences after administration of Gd-DTPA contrast in the detection of metastatic lesions in the brain.
BACKGROUND
Advances in oncology in recent years have made it possible to undertake radical interventions even in advanced cases. Local treatment, surgical or radiosurgical, is applied ever more frequently in cases of metastases to the brain. This requires accurate determination of the number and location of metastases by means of imaging techniques. The goal of our research was to establish whether the use of sequences delayed by 20-30 minutes after gadolinium injection improves the number of metastatic lesions detected in the brain by MRI.


METHODS
Twenty-eight patients were studied, ranging in age from 24 to 72 years, diagnosed with malignant tumors and suspected metastases to the brain. MRI examinations were performed with a 2T unit in SE T1 immediately after i.v. administration of a 0.1 mmol/kg dose of gadolinium, and again 20-30 minutes after contrast injection; both sequences were done in axial projection in layers identical as in the SE T1 sequence made before gadolinium injection. The focal lesions were counted and classified by size. The number of detected lesions was calculated in each group, comparing early and late phases after contrast injection.


RESULTS
The number of all nodules found in the delayed sequences was significantly higher in comparison to the early phase after gadolinium injection.


CONCLUSIONS
Delayed sequence should be used to supplement basic sequences in the diagnosis of malignant metastases to the brain in selected oncological cases.
Grzesiakowska
Urszula
U
Department of Radiology, Institute of Oncology, Warsaw, Poland.
Tacikowska
Malgorzata
M
D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology*; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media / Q000494:pharmacology*; D005260:Female; D019786:Gadolinium DTPA / Q000494:pharmacology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
D003287:Contrast Media; D019786:Gadolinium DTPA