Purpose: The aim of our study is to assess pre-contrast CT value and signal intensity loss of adrenal adenoma on dual phase chemical shift MRI.
Materials and Methods: From May 1997 to December 2004, 52 patients with adrenal adenoma were examined with pre-contrast CT and dual chemical shift MRI. Eleven of 52 were proven by surgery and the rest did not show any change for 12 months period. All patients were studied with CT (GE Hispeed Advantage SG, SP LightSpeed Qx/i-α) and 1.5 T MRI units (Magnetom Quantum and Sonata, Siemens, Germany) with a body-coil. CT was scanned with slice thickness of 3 mm, 5 mm or 10 mm, and pitch of 1. In additional to the MR routine sequences such as FLASH and HASTE, dual chemical shift sequence was scanned (TR/TE/FA＝140/2.3 and 5.2/90). Hounsfield units (HU) on pre contrast CT, signal intensity ratio (SIR), and signal noise ratio (SNR) on MRI were measured. Signal intensities were measured quantitatively in opposed-phase (OP), in-phase (IP) and background noise (N). SIRs (OP/IP) and SNRs (OP-N)/(IP-N) were calculated as well as mean and standard deviation. Using JMP (commercial analysis software), correlation analysis was performed between HU and the parameters of SIR and SNR with linear regression method.
Results: The mean and SD of CT value, SNR and SIR was 12.6 ±15.04, SNR＝0.51 ±0.28, SIR＝0.47 ±0.30, respectively. Correlation coefficient between CT value and SNR was 0.78(p <0.001), and between CT value and SIR was 0.76(p <0.001).
Discussion and conclusion: SNR and SIR of in-phase and opposed-phase study is an established method for assessing of fat and water components in the adrenal adenoma. However, CT value also has the power for the evaluation of fat element. In this study the CT vs. SIR and the CT vs. SNR were correlated well. These results suggest that CT value may show the amount of fat element in adrenal nodule. In conclusion, pre-contrast CT value could suggest a good index of a lipid component of an adrenal adenoma. The signal intensity ratios are the reliable evaluation method for diagnosis adrenal adenomas. Keywords: adrenocortical adenoma, CT attenuation, dual chemical shift imaging.

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　Pregnancy-induced toxemia is named as pregnancy-induced hypertension syndrome and its definition is based on hypertension but not in proteinuria and edema. Previously pregnancy-induced toxemia is composed of three symptoms of hypertension, proteinuria and edema. In the present study, two studies were carried out. The first study examined renal patho-histology in 30 proteinuric patients who had a past history of toxemia. Ten patients had IgA nephropathy, 10 did glomerulosclerosis and 10 did focal glomerulosclerosis. The factors, such as the age of pregnancy, the levels of blood pressure and the degree of proteinuria during pregnancy, were not significantly different among three groups. However, the levels of serum creatinine in patients with focal glomerulosclerosis were significantly lower than those with IgA nephropathy and /or with glomerulosclerosis. In addition, there was no significantly difference of the two factors between the latter two groups. These data suggest that patients who were previously defined as having pregnancy-induced toxemia were composed at least of three types of nephropathy. From this study, patients who had proteinuria during pregnancy should be carefully followed up and if proteinuria persisted more than a year renal biopsy for diagnosis of nephropathy should be considered. In the second study, 52 patients who were diagnosed as having pregnancy-induced hypertension were followed up for a year after delivery. In 9 patients, high blood pressure more than 140 mmHg systolic or 90 mmHg diastolic was maintained beyond one year. A comparison between the patients whose blood pressure became less than 140 and 90 mmHg within a year and those did not revealed a significant difference in systolic blood pressure at the presentation of pregnancy-induced hypertension syndrome although any other factors such as age, the levels of proteinuria and so on. did not show any significant differences between the two groups. From the second study, the levels of systolic blood pressure might be predictable index for development of hypertension after delivery in patients with pregnancy-induced hypertension syndrome. Combining these two studies, it is concluded that if proteinuria or high blood pressure persists more than one year after delivery more cautious follow-up would be preferable.

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