RESUMEN
We studied histology, findings on H-1 magnetic resonance (MR) imaging, and correlations of P-31 MR spectroscopy with microelectrode pH and pO2 measurements in the BA1112 rhabdomyosarcoma in WAG/Rij/Y rats. Intratumoral hemorrhage was a prominent feature on MR images and pathologic specimens. Eosinophilic necrosis could be seen microscopically but was not discernible on images. The peaks seen on P-31 MR spectra were similar to those reported in other tumors. The intratumoral pH was neutral despite low pO2 values and P-31 MR evidence for impaired metabolic status.
Asunto(s)
Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Rabdomiosarcoma/diagnóstico , Animales , Concentración de Iones de Hidrógeno , Trasplante de Neoplasias , Oxígeno/fisiología , Presión Parcial , Ratas , Rabdomiosarcoma/patología , Rabdomiosarcoma/fisiopatologíaRESUMEN
The authors studied the influence of gating, cardiac cycle, and timing of rephasing gradients upon the detection of pulmonary emboli by MRI. Serial single-section MR images were obtained in normal dogs and dogs with experimental pulmonary emboli. Images with cardiac gating, respiratory gating, and ungated images were obtained. Cardiac gating in systole and late magnetization rephasing had the best diagnostic accuracy. Gated images were clearly superior to ungated; with combined cardiac and respiratory gating, sensitivity was 82% and specificity 88%. These results are sufficiently promising to warrant further studies.