1.The Radiation Dose Absorbed by Healthy Parenchyma Is a Predictor for the Rate of Contralateral Hypertrophy After Unilobar Radioembolization of the Right Liver
Nazim COSKUN ; Aslihan YILDIRIM ; Alptug Ozer YUKSEL ; Murat CANYIGIT ; Elif OZDEMIR
Korean Journal of Nuclear Medicine 2022;56(6):291-298
Purpose:
To investigate the predictors of contralateral hypertrophy in patients treated with unilobar transarterial radioembolization (TARE) with yttrium-90-loaded resin microspheres due to unresectable right-liver tumors.
Methods:
Patients who underwent right unilobar TARE with resin microspheres between May 2019 and September 2021 were screened retrospectively. Contralateral hypertrophy was evaluated by calculating the kinetic growth rate (KGR) in 8–10 weeks after TARE. The predictors of increased KGR were determined with linear regression analysis.
Results:
A total of 24 patients (16 with primary and 8 with metastatic liver tumors) were included in the study. After right unilobar TARE, mean volume of the left lobe increased from 368.26 to 436.16 mL, while the mean volume of the right lobe decreased from 1576.22 to 1477.89 mL. The median KGR of the left lobe was 0.28% per week. The radiation dose absorbed by the healthy parenchyma of the right lobe was significantly higher in patients with increased KGR (31.62 vs. 18.78 Gy, p = 0.037). Linear regression analysis showed that the dose absorbed by healthy parenchyma was significantly associated with increased KGR (b = 0.014, p = 0.043).
Conclusion
Patients who received right unilobar TARE for liver malignancies could develop a substantial contralateral hypertrophy, and the radiation dose absorbed by the healthy parenchyma of the right lobe was significantly associated with increased KGR in the left lobe. TARE could have a role for inducing contralateral hypertrophy as it offers the advantage of concurrent local tumor control along with its hypertrophic effect.
2.The Impact of Warmed Intravenous Contrast Material on the Bolus Geometry of Coronary CT Angiography Applications.
Tuncay HAZIROLAN ; Baris TURKBEY ; Erhan AKPINAR ; Murat CANYIGIT ; Musturay KARCAALTINCABA ; Bora PEYNIRCIOGLU ; Z Dicle BALKANCI ; Deniz AKATA ; Ferhun BALKANCI
Korean Journal of Radiology 2009;10(2):150-155
OBJECTIVE: This study was designed to investigate the effect of administration of warmed contrast material (CM) on the bolus geometry and enhancement as depicted on coronary CT angiography. MATERIALS AND METHODS: A total of 64 patients (42 men, 22 women; mean age, 56 years) were randomly divided into two groups. Group 1 included 32 patients administered CM (Omnipaque [Iohexol] 350 mg I/ mL; Nycomed, Princeton, NJ) saline solutions kept in an incubator at a constant temperature (37degrees C). Group 2 included 32 patients administered the CM saline solutions kept at constant room temperature (24degrees C). Cardiac CT scans were performed with a dual source computed tomography (DSCT) scanner. For each group, region of interest curves were plotted inside the ascending aorta, main pulmonary artery and descending aorta on test bolus images. Using enhancement values, time/enhancement diagrams were produced for each vessel. On diagrams, basal Hounsfield unit (HU) values were subtracted from sequentially obtained values. A value of 100 HU was accepted as a cut-off value for the beginning of opacification. The time to peak, the time required to reach 100 HU opacification, maximum enhancement and duration of enhancement above 100 HU were noted. DSCT angiography studies were evaluated for coronary vessel enhancement. RESULTS: Maximum enhancement values in the ascending aorta, descending aorta and main pulmonary artery were significantly higher in group 1 subjects. In the ascending aorta, the median time required to reach 100 HU opacification during the test bolus analysis was significantly shorter for group 2 subjects than for group 1 subjects. In the ascending aorta, the descending aorta and main pulmonary artery, for group 1 subjects, the bolus geometry curve shifted to the left and upwards as compared with the bolus geometry curve for group 2 subjects. CONCLUSION: The use of warmed CM yields higher enhancement values and a shorter time to reach maximum enhancement duration, resulting in a shift of the bolus geometry curve to the left that may provide optimized image quality.
Adult
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Aged
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Contrast Media/*administration & dosage
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*Coronary Angiography
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Female
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Humans
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Image Enhancement
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Image Processing, Computer-Assisted
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Injections, Intravenous
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Iohexol/*administration & dosage
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Male
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Middle Aged
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Prospective Studies
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*Temperature
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Tomography, X-Ray Computed