• Journal of Magnetics
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• 제19권3호
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• pp.261-265
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• 2014

Three-dimensional computed tomography is an effective tool to estimate the liver volume of living donors for the live liver transplantation. When additional operation is required, magnetic resonance imaging is conducted to determine the safety of the donor. This study compared the accuracy of magnetic resonance imaging and computed tomography in estimating 3D liver volume of 23 male and 7 female donors who underwent both magnetic resonance imaging and computed tomography tests before the transplantation. The analysis was conducted to see whether the liver's estimated total volumes and the left lobe volumes obtained from 3D-magnetic resonance imaging and 3D-computed tomography were identical. Volumes of the right lobe estimated with 3D-magnetic resonance imaging and 3D-computed tomography were compared with the actual volume of the right lobe harvested in the operating room because the volume of the right lobe is an important determinant in the safety of the donor. The total volume of the liver estimated from 3D-magnetic resonance imaging and 3D-computed tomography differed (1238.1904 units and 1402.364 units respectively). The left lobe volume of the liver estimated with 3D-magnetic resonance imaging and 3D-computed tomography also differed (450.530 units and 554.490 units, respectively). The right lobe volume of the liver estimated with 3D-magnetic resonance imaging and 3D-computed tomography were 787.660 units and 847.545 units, respectively, while the actual average right lobe volume of the harvested liver was 678.636 units. 3D-computed tomography has been widely used to estimate the right lobe volume of the donors' liver. However, 3D-magnetic resonance imaging was also very effective in estimating the volume of the liver. Thus, 3D-magnetic resonance imaging is also expected to become an important tool in determining the safety of the donors before transplantation.

• Radiation Oncology Journal
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• 제32권2호
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• pp.77-83
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• 2014

Purpose: To determine the prognostic and predictive value of liver volume in colorectal cancer patients with unresectable liver metastases. Materials and Methods: Sixteen patients received whole liver radiotherapy (WLRT) between January 1997 and June 2013. A total dose of 21 Gy was delivered in 7 fractions. Results: The median survival time after WLRT was 9 weeks. In univariate analysis, performance status, serum albumin and total bilirubin level, liver volume and extrahepatic metastases were associated with survival. The mean liver volume was significantly different between subgroups with and without pain relief (3,097 and 4,739 mL, respectively; p = 0.002). Conclusion: A larger liver volume is a poor prognostic factor for survival and also a negative predictive factor for response to WLRT. If patients who are referred for WLRT have large liver volume, they should be informed of the poor prognosis and should be closely observed during and after WLRT.

• 한국의학물리학회지:의학물리
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• 제19권3호
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• pp.178-185
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• 2008

간경변 및간암 환자의 증가로 간이식술의 필요성이 점점 증가되고 있고, 특히 공여자의 생체 간이식은 간이식술의 주된 분야를 차지하고 있으며 간이식 수술 전 공여자에서 간체적의 정확한 측정은 수술 후 공여자와 수여자의 간기능을 예측하는데 있어 중요한 자료가 되며, 성공적인 수술과 환자의 예후에 밀접한 영향을 미친다. 그러나 현재 환자의 간체적을 구하는 과정은 환자의 모든 CT 영상위의 간을 수작업을 통해 영상분할한 후에 3차원 간체적을 구하고 있으며 많은 시간과 노력이 필요한 작업이다. 이러한 문제를 해결하기 위해서 본 논문에서는 자동으로 간과 비장을 문턱값처리, 형태학적 영상처리, 3차원 영역확장법등의 기법을 이용하여 분할하는 알고리즘을 개발하여 체적을 구하는 시간을 단축하였다. 이러한 알고리즘의 정확성을 평가하기 위해서 동물의 실제 간과 비장을 팬텀으로 제작하여 실제 측정한 체적과 알고리즘으로 분할된 영상의 결과를 비교 평가하였다. 문턱치값의 설정에 따라 다른 결과를 보이는 특성이 있지만 자동으로 문턱치를 결정했을 때 비장과 간의 체적측정 오차는 9.27%, -4.52%이었으며, 수동으로 문턱치를 결정했을 때 최소 오차가 각각 0.2%, 0.17%의 결과를 보였다. 이러한 팬텀 연구를 통해 자동 분할 알고리즘으로 얻은 체적의 결과가 정확성과 재현성을 보여주어 추후 간체적을 구하는 보조수단으로 활용될 수 있을 것이라 예상된다.

• 대한핵의학회지
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• 제17권1호
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• pp.55-62
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• 1983

In 16 volunteers without clinical or laboratory evidence of liver disease, liver volume was determined using single-photon emission computed tomography(ECT). This technique provided excellent object contrast between the liver and its surroundings and permitted calculation of liver volume without geometric assumptions about the liver's configuration. Reproducibility of results was satisfactory, with a root-me an-square error of less than 2% between duplicate measurements in 16 individuals. The volume measurements were validated by the use of phantoms.

• Korean Journal of Radiology
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• 제23권7호
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• pp.720-731
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• 2022

Objective: We aimed to develop and test a deep learning algorithm (DLA) for fully automated measurement of the volume and signal intensity (SI) of the liver and spleen using gadoxetic acid-enhanced hepatobiliary phase (HBP)-magnetic resonance imaging (MRI) and to evaluate the clinical utility of DLA-assisted assessment of functional liver capacity. Materials and Methods: The DLA was developed using HBP-MRI data from 1014 patients. Using an independent test dataset (110 internal and 90 external MRI data), the segmentation performance of the DLA was measured using the Dice similarity score (DSS), and the agreement between the DLA and the ground truth for the volume and SI measurements was assessed with a Bland-Altman 95% limit of agreement (LOA). In 276 separate patients (male:female, 191:85; mean age ± standard deviation, 40 ± 15 years) who underwent hepatic resection, we evaluated the correlations between various DLA-based MRI indices, including liver volume normalized by body surface area (LV_BSA), liver-to-spleen SI ratio (LSSR), MRI parameter-adjusted LSSR (aLSSR), LSSR × LV_BSA, and aLSSR × LV_BSA, and the indocyanine green retention rate at 15 minutes (ICG-R15), and determined the diagnostic performance of the DLA-based MRI indices to detect ICG-R15 ≥ 20%. Results: In the test dataset, the mean DSS was 0.977 for liver segmentation and 0.946 for spleen segmentation. The Bland-Altman 95% LOAs were 0.08% ± 3.70% for the liver volume, 0.20% ± 7.89% for the spleen volume, -0.02% ± 1.28% for the liver SI, and -0.01% ± 1.70% for the spleen SI. Among DLA-based MRI indices, aLSSR × LV_BSA showed the strongest correlation with ICG-R15 (r = -0.54, p < 0.001), with area under receiver operating characteristic curve of 0.932 (95% confidence interval, 0.895-0.959) to diagnose ICG-R15 ≥ 20%. Conclusion: Our DLA can accurately measure the volume and SI of the liver and spleen and may be useful for assessing functional liver capacity using gadoxetic acid-enhanced HBP-MRI.

• Investigative Magnetic Resonance Imaging
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• 제20권4호
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• pp.231-240
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• 2016

Purpose: To determine whether liver stiffness (LS) measured by magnetic resonance elastography (MRE) can predict the outcome of radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC) patients. Materials and Methods: A total of 107 patients with Child-Pugh class A liver function who were treated with RFA for single HCC and who had undergone a gradient-echo MRE within 6 months before RFA were included. We evaluated the relationship between the LS values and the ablation volume, local tumor progression (LTP), and intrahepatic distant recurrence (IDR). We also constructed receiver operating characteristic (ROC) curves to examine the role of LS in predicting liver function deterioration, which was defined as an increase of Child-Pugh score by one point or more at 1 year after RFA. Results: There was no significant correlation between LS and ablation volume, and neither time to LTP nor IDR was associated with LS. Among the 66 patients who did not have recurrence 1 year after RFA, 5 patients (7.6%) developed liver function deterioration. A high LS value was significantly associated with development of liver function deterioration after RFA and the area under the ROC curve was 0.764 (95% CI 0.598-0.929, P = 0.003). Conclusion: LS measured by MRE could not predict ablation volume and tumor recurrence. However, high LS values were significantly associated with development of liver function deterioration.

• The Korean Journal of Physiology
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• 제2권1호
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• pp.9-15
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• 1968

Changes in gastrointestinal tissue blood volume induced by variations of venous pressure between 6 and 40 mmHg were studied in 32 rabbits. Venous pressure lowering was produced by withdrawal of appropriate volume of blood and venous pressure elevation was obtained by partial occlusion of intra-thoracic vena cava inferior. Estimation of regional tissue blood volume was performed by means of regional distribution of injected $Cr^{51}-labeled$ red blood cells. The following results were obtained. 1. At the normal control venous pressure value of 18 mmHg, spleen showed the highest value of tissue blood volume expressed on weight basis, namely, $111{\mu}l/gm$, Liver tissue blood volume was $95\;{\mu}l/gm$, small intestine 24 and stomach $21\;{\mu}l/gm$, respectively. 2. Linear relationships were observed between venous pressure change and gastrointestinal tissue blood volume. The coefficients of correlation were: in spleen r=0.723; in liver r=0.791; in stomach r=0.704, respectively. In small intestine the relationship was less clear and r=0.358. Tissue blood volume of extrabdominal tissue, such as M. gastrocnemius was not influenced by venous pressure change. 3. The highest change in tissue blood volume expressed on weight basis was observed in spleen. The liver tissue showed the next highest change. Change in total tissue blood volume, however, was greatest in liver and next greatest in small intestine. This was interpreted by the fact that total weight of these two organs was much greater than that of spleen. 4. The mechanism that the change in tissue blood volume lies in the venous system which has a great compliance was discussed.

• Journal of International Society for Simulation Surgery
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• 제1권1호
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• pp.37-40
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• 2014

Purpose For living donor liver transplantation, liver segmentation is difficult due to the variability of its shape across patients and similarity of the density of neighbor organs such as heart, stomach, kidney, and spleen. In this paper, we propose an automatic segmentation of the liver using multi-planar anatomy and deformable surface model in portal phase of abdominal contrast-enhanced CT images. Method Our method is composed of four main steps. First, the optimal liver volume is extracted by positional information of pelvis and rib and by separating lungs and heart from CT images. Second, anisotropic diffusing filtering and adaptive thresholding are used to segment the initial liver volume. Third, morphological opening and connected component labeling are applied to multiple planes for removing neighbor organs. Finally, deformable surface model and probability summation map are performed to refine a posterior liver surface and missing left robe in previous step. Results All experimental datasets were acquired on ten living donors using a SIEMENS CT system. Each image had a matrix size of $512{\times}512$ pixels with in-plane resolutions ranging from 0.54 to 0.70 mm. The slice spacing was 2.0 mm and the number of images per scan ranged from 136 to 229. For accuracy evaluation, the average symmetric surface distance (ASD) and the volume overlap error (VE) between automatic segmentation and manual segmentation by two radiologists are calculated. The ASD was $0.26{\pm}0.12mm$ for manual1 versus automatic and $0.24{\pm}0.09mm$ for manual2 versus automatic while that of inter-radiologists was $0.23{\pm}0.05mm$. The VE was $0.86{\pm}0.45%$ for manual1 versus automatic and $0.73{\pm}0.33%$ for manaual2 versus automatic while that of inter-radiologist was $0.76{\pm}0.21%$. Conclusion Our method can be used for the liver volumetry for the pre-surgery planning of living donor liver transplantation.

• Radiation Oncology Journal
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• 제30권4호
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• pp.189-196
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• 2012

Purpose: To investigate the safety of high dose hypofractionated radiotherapy (RT) in patients with small hepatocellular carcinoma (HCC) in terms of liver volumetric changes and clinical liver function. Materials and Methods: We retrospectively reviewed 16 patients with small HCC who were treated with high dose hypofractionated RT between 2006 and 2009. The serial changes of the liver volumetric parameter were analyzed from pre-RT and follow-up (FU) computed tomography (CT) scans. We estimated linear time trends of whole liver volume using a linear mixed model. The serial changes of the Child-Pugh (CP) scores were also analyzed in relation to the volumetric changes. Results: Mean pre-RT volume of entire liver was 1,192.2 mL (range, 502.6 to 1,310.2 mL) and mean clinical target volume was 14.7 mL (range, 1.56 to 70.07 mL). Fourteen (87.5%) patients had 4 FU CT sets and 2 (12.5%) patients had 3 FU CT sets. Mean interval between FU CT acquisition was 2.5 months. After considering age, gender and the irradiated liver volume as a fixed effects, the mixed model analysis confirmed that the change in liver volume is not significant throughout the time course of FU periods. Majority of patients had a CP score change less than 2 except in 1 patient who had CP score change more than 3. Conclusion: The high dose hypofractionated RT for small HCC is relatively safe and feasible in terms of liver volumetric changes and clinical liver function.

• Preventive Nutrition and Food Science
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• 제20권4호
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• pp.266-275
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• 2015

Exposure to cadmium (Cd) has harmful effects on the liver and kidney. Resveratrol (RES) is an herbal substance that functions as a protective mediator. This study aimed to investigate the effects of RES on the histology of liver and kidney in Cd-exposed mice. Male mice were divided into 4 groups daily receiving normal saline (1 mL normal saline/d), Cd (1 mg/kg/d), RES (20 mg/kg/d), and Cd plus RES, respectively. After 4 weeks, the liver and kidney components were evaluated using stereological methods. The total volume and number of hepatocytes, and volume of fibrous tissue were respectively increased by 34%, 58%, and a 3-fold in the Cd-exposed mice in comparison to the control animals (P<0.03). On the other hand, the volume of the main vasculature (sinusoids and central veins) was decreased by 36% in the Cd group compared to the control mice (P<0.03). Considering the kidney, the results showed a 3-fold increase in the total glomeruli volume and a 7-fold increase in fibrous tissue in the Cd-treated group compared to the control mice (P<0.03). After Cd treatment, a 32% reduction was observed in the volume and length of the proximal and distal convoluted tubules. RES-treatment alone did not induce any structural changes. In comparison to the Cd group, an increase in the normal components of the liver and kidney and a decrease in the formation of the fibrous and degenerated tissues were observed in the Cd+RES-treated mice (P<0.03).