Evaluation of adrenal masses using FIESTA-MRI sequence

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1 Evaluation of adrenal masses using FIESTA-MRI sequence 14.September.2018/Friday / Room 3 / GÖKHAN PEKİNDİL, FATMA CAN, CELAL BAYAR UNIVERSITY MEDICAL FACULTY DEP. OF RADIOLOGY MANİSA-TURKEY

2 Evaluation of adrenal masses using FIESTA-MRI sequence FIESTA (Fast Imaging Employing Steady-state Acquisition) sequence (GE Trademark (TrueFISP-Siemens / Balanced FFE-Philips) Ultrafast pulse sequence it is usually used as an adjunct to conventional T1-and T2-weighted sequences for superb anatomical details of abdomen

3 Signal changes noted on FIESTA sequence images are nonspecific Neither T2W nor T1W but looks like T2W

4 The main advantages of the FIESTA sequence Fast scaning time: sec its motion insensitivity insensitivity to flow void artifacts. higher contrast when compared with the FSE or the SSFSE pulse sequence, and sharp edge definition,

5 Evaluation of adrenal masses using FIESTA-MRI sequence SI.1178 SI.317 İn phase T1W Out of phase T1W Sı. 46 sı. 127 FIESTA FIESTA

6 Evaluation of adrenal masses using FIESTA-MRI sequence Therefore; We hypothesized that lipid rich adrenal adenomas may show decreased SI on FIESTA images, since most of the adrenal adenomas have intracellular fat We attempted to evaluate lipid rich adrenal adenomas comparing with non adenomas using FIESTA sequence in this study This is the FIRST study in the literature

7 Material and methods Retrospective study / only intracellular fat containing adenomas included 50 cases of typical adrenal adenoma which had intracellular fat diagnosed using inand-out of phase axial MRI images Lipid poor adrenal adenomas and fatty livers have not been included in the study 10 cases of adrenal non-adenomas for comparison (ASII < 20 %) Adrenal signal intensity index (ASII) > more than 20 % diagnostic criteria ASII = [(signal intensity on in-phase imaging signal intensity on out-phase imaging) (signal intensity on in-phase imaging)] 100% ASII: x100 = 90 % 1112 In phase Out of phase

8 Materials and Methods Mean Signal intensities (SI) of adrenal masses, liver, spleen parenchyma and psoas muscle were measured using 3 ROIs ( 3 cm2) on coronal FIESTA images and mean SI values were calculated liver adrenal sspleen psoas

9 Materials and Methods SI of Adrenal masses were compared with the SI of liver, spleen and muscle Ratios of : adrenal mass to- Liver ratio adrenal mass- to-spleen ratio adrenal mass to-psoas muscle ratio were calculated These values were also compared with the values of ASII of adrenal masses All values were also statistically compared or corraleted using Pearson correlation, T-test and Mann witney U test

10 Materials and Methods 1.5 Tesla MRI machine- GE was used All cases had Coronal FIESTA, axial T2W-T1W, axial T1 in-and-out of phases, LAVA dynamic contrast enhanced axial images (four phases) and DW-MRI images of upper abdomen Coronal FIESTA is performed using the following acquisition parameters: (TR/ TE: 2,000/150, Flip angle:70, bandwith: 83,33) ; Acquisition timing ( freq:256, phase:288, Nex:1, phase FOV:1, Acqs before pause:10); scanning range ( FOV:40, slice thickness:7, spacing:1).

11 Results 1. group: Adrenal lipid rich adenomas : 50 cases 26 female, 24 male between (24-80 y/o) mean: 58 years old Size of adenoma: longest diameter: mm, (mean 22 mm), ASII between % transvers diameter: mm.(mean 16 mm)

12 Case: Adrenal Adenoma In-phase SI: 196 Out phase SI: 84 ASII: 57% Liver SI: 86 Spleen SI: 82 Psoas muscle SI: 37 Adenoma SI: 48 In-phase SI: 196 Out phase SI: 84 ASII: 55%

13 Adrenal Adenoma Group FIESTA sequence Minimum SI Maximum SI Mean SI Adenoma SI İn phase SI Out of phase SI ASII % 38 % 88 % %67 Liver SI Psoas Muscle SI Spleen SI

14 Non-adenoma Group 2. Group Non adenoma: 10 cases 4 female, 6 male between (36-69 y/o) mean 55 years old Size of adrenal mass; longest diameter: mm. (mean 49 mm.), transvers diameter: mm. (mean 38 mm.) Adrenal Non-adenoma final diagnosis Metastases 4 Pheochromacytoma 4 Lymphoma 1 Adrenocortical carcinoma 1 Number of cases

15 Case: Adrenal Lymphoma İn phase Out of phase Adrenal mass Sİ: 100 In faz Sİ: 532 Out faz Sİ:532 ASII 0% Liver SI. 72 Spleen SI. 278

16 Case: Metastases Adrenal mass SI: 136 In phase Sİ: 175 Out phase Sİ: 157 ASII: 10% Liver SI: 77 Spleen SI 141

17 Case: Pheochromacytoma Adrenal mass SI: 297 In phase SI: 267 Out phase SI: 261 ASII: 2% Liver SI: 130 Spleen 172

18 Case: Adrenocortical Carcinoma Adrenal mass SI: 134 In phase SI: 305 Out-phase SI:275 ASII: 9% Liver SI:109 Spleen SI 194

19 Results Adrenal non-adenomas FIESTA SEQUENCE Mean Signal Intensity (SI) Adrenal non-adenomas 175 Liver 106 Psoas muscle 52 Spleen 173 İn phase 333 Out of phase 325 Signal Intensity Index 2%

20 Results Adrenal Adenomas vs non-adenomas FIESTA sequence Mean Signal Intensity FIESTA sequence Mean Signal Intensity Adrenal Adenoma 73 In phase 520 Out phase 160 ASII %67 Liver 108 Psoas muscle 52 Spleen 173 Non-Adenoma 175 In phase 333 Out phase 325 ASII % 2 Liver 106 Psoas muscle 52 Spleen 191

21 Adrenal lipid rich Adenoma Mean SI on FIESTA sequence Number of case Mean SI on FIESTA Adrenal non-adenoma *Mann-Whitney U p< Statistically Significant Difference

22 Statistical Results ****There are 2 significant correlations Pearson correlation test Adenoma SI & ASII % Adenoma SI & outfaz SI Adenoma-to-liver ratio & ASII % Adenoma-to-spleen ratio & ASII % Adenoma-to-psoas m. ratio & ASII% Adenoma SI & Spleen SI -0,036 poor negative 0,102 moderate positive 0,117 moderate positive -0,264 strongest negative -0,011 poor negative 0.646** strongest positive correlation Liver & psoas muscle SI 0.523** Liver & Spleen SI 0.484**

23 Results SI of Adenomas <lower than (Both Liver SI+Spleen SI) 96 % of cases SI of Adenomas equal = or >higher than Liver SI only in 2 cases SI of Adenomas <lower than Spleen SI 96% of cases (2 cases equal SI) SI of Nonadenomas >higher than Liver in 9 cases 90% only in 1 case less than liver SI of Nonadenomas > higherthan Spleen in 3 cases 30% in 7 cases slightly less than liver Our results show that there are overlapping SI values and gray zones for SI Probably it is arised from that intracellular fatty fraction of adenomas may show great variations, therefore if lipid component of adenoma is less, the difference of SI of adenoma and both liver and spleen Sıs are less and overlapping values may be seen

24 Practical Visually comparison Adenoma Typical 120 Adenoma Adenoma? Typical Adenoma Non adenoma-pheochroma

25 Conclusions As expected the adenoma SI to spleen SI ratio is the most valuable in this study Probably: SI of the Spleen parenchyma is not influenced many degenerations such as fatty infiltration of the liver And SI of psoas may also change depending on age of the case, physical activity, degenerative changes of muscleskeletal system etc.

26 Conclusion This study ONLY confirms that Intracellulary lipid rich adenomas can be revealed by proportional decreased signal intensity on FIESTA sequence. More lipid = More decreased signal on FIESTA The signal drop in a fat-containing tissue on the FIESTA sequence is similar to the in- and out-of-phase pulse sequences. Comprehensive evaluation of all the sequences acquired is needed to reach a correct diagnosis of adrenal adenomas however the FIESTA technique can be used only as an adjunct to the routine examination.

27 Conclusion FIESTA sequence may have a role in demonstration of intracellulary lipid component of the adrenal adenomas in cases who had more artifacts at in-and-out of phase imaging This study should be accepted as an initial study It is clear that studies with larger groups comparing of both lipid rich and poor adenomas with non adenomas are needed to reveal clinical impact of the study. Thank you for your attention!