An-Hua Li

Sun Yat-Sen University Cancer Center, Shengcheng, Guangdong, China

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Publications (15)34.66 Total impact

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    ABSTRACT: Breast ultrasound images along coronal plane contain important diagnosis information. However, conventional clinical 2D ultrasound cannot provide such images. In order to solve this problem, we developed a novel ultrasound system aimed at providing breast coronal images. In this system, a spatial sensor was fixed on an ultrasound probe to obtain the image spatial data. A narrow-band rendering method was used to form coronal images based on B-mode images and their corresponding spatial data. Software was developed for data acquisition, processing, rendering and visualization. In phantom experiments, 20 inclusions with different size (5–20 mm) were measured using this new system. The results obtained by the new method well correlated with those measured by a micrometer (y = 1.0147x, R2 = 0.9927). The phantom tests also showed that this system had excellent intra- and inter-operator repeatability (ICC > 0.995). Three subjects with breast lesions were scanned in vivo using this new system and a commercially available three-dimensional (3D) probe. The average scanning times for the two systems were 64 s and 74 s, respectively. The results revealed that this new method required shorter scanning time. The tumor sizes measured on the coronal plane provided by the new method were smaller by 5.6–11.9% in comparison with the results of the 3D probe. The phantom tests and preliminary subject tests indicated the feasibility of this system for clinical applications by providing additional information for clinical breast ultrasound diagnosis.
    Ultrasonics 09/2014; · 2.03 Impact Factor
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    ABSTRACT: Spatial annotation is an essential step in breast ultrasound imaging, because the follow-up diagnosis and treatment are based on this annotation. However, the current method for annotation is manual and highly dependent on the operator's experience. Moreover, important spatial information, such as the probe tilt angle, cannot be indicated in the clinical 2-D annotations. To solve these problems, we developed a semi-automated 3-D annotation method for breast ultrasound imaging. A spatial sensor was fixed on an ultrasound probe to obtain the image spatial data. Three-dimensional virtual models of breast and probe were used to annotate image locations. After the reference points were recorded, this system displayed the image annotations automatically. Compared with the conventional manual annotation method, this new annotation system has higher accuracy as indicated by the phantom test results. In addition, this new annotation method has good repeatability, with intra-class correlation coefficients of 0.907 (average variation: ≤3.45%) and 0.937 (average variation: ≤2.85%) for the intra-rater and inter-rater tests, respectively. Breast phantom experiments simulating clinical breast scanning further indicated the feasibility of this system for clinical applications. This new annotation method is expected to facilitate more accurate, intuitive and rapid breast ultrasound diagnosis.
    Ultrasound in medicine & biology 12/2013; · 2.46 Impact Factor
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    ABSTRACT: There is a strong need for early assessment of tumor response to chemotherapy in order to avoid the adverse effects of unnecessary chemotherapy and to allow early transition to second-line therapy. The purpose of this study was to determine the feasibility of ultrasonic spectral analysis for the in vivo characterization of changes in tumor microstructure in the evaluation of tumor response to chemotherapy using diagnostic ultrasound. Experiments were approved by the regional animal care committee. Twenty-four MCF-7 breast cancer bearing nude mice were treated with adriamycin or sterile saline administered by intraperitoneal injection. Ultrasonic radio-frequency (RF) data was collected using a clinically available ultrasound scanner (6-MHz linear transducer). Linear regression parameters (spectral slope and midband-fit) regarding the calibrated power spectra from the RF signals were tested to monitor tumor response to treatment. The section equivalent to the ultrasound imaging plane was stained with hematoxylin and eosin to allow for assessment of the density of tumor cell nuclei. Treatment with adriamycin significantly reduced tumor growth in comparison with the control group (p = 0.003). Significant changes were observed in the ultrasonic parameters of the treated relative to the untreated tumors (p < 0.05). The spectral slope increased by 48.5%, from -10.66 +/- 2.96 to -5.49 +/- 2.69; the midband-fit increased by 12.8%, from -57.10 +/- 7.68 to -49.81 +/- 5.40. Treated tumors were associated with a significant decrease in the density of tumor cell nuclei as compared with control tumors (p < 0.001). Ultrasonic spectral analysis can detect changes in tumor microstructure after chemotherapy, and this will be helpful in the early evaluation tumor response to chemotherapy.
    BMC Cancer 06/2013; 13(1):302. · 3.33 Impact Factor
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    ABSTRACT: BACKGROUND: Currently used morphologic criteria have limitations in assessing tumor response to chemotherapy because of the relatively slow tumor shrinkage as measured by conventional morphologic imaging. Functional imaging techniques show promising results in early assessment of tumor response to treatment. PURPOSE: To quantitatively detect changes in tumor perfusion during chemotherapy with contrast-enhanced ultrasound. MATERIAL AND METHODS: Twenty-three MCF-7 breast cancer bearing nude mice treated by either adriamycin (n 11) or sterile saline (n 12) were imaged before and after treatment with an ultrasound scanner after bolus injection of SonoVue. Regions of interest within the tumor were analyzed offline to determine perfusion parameters including peak enhancement (PE), area under the curve of wash-in (WiAUC), rise time (RT), wash-in rate (WiR), wash-in perfusion index (WiPI), and quality of fit (QOF). Hematoxylin and eosin was used to assess tumor cell density and immunohistochemical analysis was performed for evaluation of microvascular density (MVD). RESULTS: Treatment with adriamycin significantly reduced tumor growth in comparison to the control group (P < 0.001). There was no significant difference in perfusion parameters before treatment. Treatment with adriamycin resulted in a significant decrease in PE, WiAUC, WiR, and WiPI in comparison with control group (P < 0.01). The tumor cell density estimated by pathology slice was significantly lower in treated tumors than in control tumors after treatment (P < 0.001). Immunohistochemistry showed significant decreases of MVD in treated tumors as compared with control tumors (P < 0.001) after treatment. CONCLUSION: Quantitative contrast-enhanced ultrasound can detect the change of tumor perfusion after chemotherapy, which may enable early assess tumor response to chemotherapy.
    Acta Radiologica 05/2013; · 1.33 Impact Factor
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    ABSTRACT: There is a strong need to assess early tumor response to chemotherapy in order to avoid adverse effects from unnecessary chemotherapy and allow early transition to second-line therapy. This study was to quantify tumor perfusion changes with dynamic contrast-enhanced ultrasound (CEUS) in the evaluation of early tumor response to cytotoxic chemotherapy. Sixty nude mice bearing with MCF-7 breast cancer were administrated with either adriamycin or sterile saline. CEUS was performed on days 0, 2, 4 and 6 of the treatment, in which time-signal intensity (SI) curves were obtained from the intratumoral and depth-matched liver parenchyma. Four perfusion parameters including peak enhancement (PE), area under the curve of wash-in (WiAUC), wash-in rate (WiR) and wash-in perfusion index (WiPI) were calculated from perfusion curves and normalized with respect to perfusion of adjacent liver parenchyma. Histopathological analysis was conducted to evaluate tumor perfusion, tumor cell density, microvascular density (MVD) and proliferating cell density. Significant decreases of tumor normalized perfusion parameters (i.e., nPE, nWiAUC, nWiR and nWiPI) were noticed between adriamycin-treated and control groups (<0.01) 2 days after therapy. There were significant differences of tumor volumes between control and treated groups on day 6 (<0.001) while there were no significant differences in tumor volume on days 0, 2 and 4 (>0.05). Significant decreases of tumor perfusion, tumor cell density, MVD and proliferating cell density were seen in adrianycin-treated group 2 days after therapy when compared to control group (<0.001). Dynamic CEUS for quantification of tumor perfusion could be used for early detection of cancer response to cytotoxic chemotherapy prior to notable tumor shrinkage.
    PLoS ONE 05/2013; 8(3):e58274. · 3.53 Impact Factor
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    ABSTRACT: Objectives The purpose of the study was to detect tumor blood flow changes after chemotherapy with contrast-enhanced destruction-replenishment sonography. Methods Twenty-four MCF-7 breast cancer-bearing nude mice were included in this study. Animals received either adriamycin or sterile saline and underwent contrast-enhanced sonography before and after treatment using a destruction-replenishment technique. A monoexponential function, y = A(1 - e(-βt)), was used to fit the replenishment kinetics, where the plateau signal intensity A reflects the percent blood volume; the time constant β reflects the average speed of blood; and their product A*β reflects the nutrient blood flow. Tumor blood perfusion was compared to measurements of cell density and microvascular density. Results Volumes of the treated tumors were significantly reduced after 7 days of adriamycin treatment compared with the control tumors (P < .001). Before adriamycin administration, there was no significant difference in blood perfusion between the treated and control groups (P > .05). Treatment with adriamycin resulted in a significant decrease in A, β, and A*β (P <.001) compared with the control tumors. The tumor cell density and microvascular density estimated by pathologic slices were significantly lower in the treated tumors than in the control tumors (P <.001). Conclusions Quantification of tumor blood flow using contrast-enhanced destruction-replenishment sonography shows the potential to evaluate tumor responses to chemotherapy.
    Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 04/2013; 32(4):683-90. · 1.40 Impact Factor
  • The British journal of radiology 02/2013; · 2.11 Impact Factor
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    ABSTRACT: Portal vein embolization (PVE) has become a standard preoperative procedure to promote hypertrophy of the future remnant liver to reduce postoperative liver failure. Whether PVE accelerates tumor growth is still controversial. We developed a left PVE procedure and investigated its effect on liver hypertrophy and tumor growth in a rabbit liver tumor model. VX2 tumors were implanted in both the external left and right middle lobe (the bilateral group) or in the external left lobe only (the unilateral group) of rabbit liver. Both groups were further divided into a PVE or a sham/control group. Tumor volume and tumor growth rate as volume relative increase were determined by ultrasound. Liver volume-to-body weight index, an index for liver volume, was compared. Serum HGF was measured by ELISA. In the bilateral PVE group, tumor volume and relative increase value in the nonembolized lobe were significantly (71% and 65%, respectively) greater than those in the control group at 5 d post-PVE. In the unilateral PVE group, liver volume-to-body weight index of the nonembolized lobes was significantly increased by 17%. Increase of serum HGF level after PVE was correlated well with both tumor growth and liver hypertrophy. Left PVE promoted both the growth of implanted tumors and liver hypertrophy in the nonembolized liver, in which serum HGF might play an important role.
    Journal of Surgical Research 04/2012; 178(1):255-63. · 2.02 Impact Factor
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    ABSTRACT: This paper introduces a new graph-based method for segmenting breast tumors in US images. BACKGROUND AND MOTIVATION: Segmentation for breast tumors in ultrasound (US) images is crucial for computer-aided diagnosis system, but it has always been a difficult task due to the defects inherent in the US images, such as speckles and low contrast. The proposed segmentation algorithm constructed a graph using improved neighborhood models. In addition, taking advantages of local statistics, a new pair-wise region comparison predicate that was insensitive to noises was proposed to determine the mergence of any two of adjacent subregions. Experimental results have shown that the proposed method could improve the segmentation accuracy by 1.5-5.6% in comparison with three often used segmentation methods, and should be capable of segmenting breast tumors in US images.
    Ultrasonics 08/2011; 52(2):266-75. · 2.03 Impact Factor
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    ABSTRACT: To quantify tumor blood flow by using contrast material-enhanced destruction-replenishment ultrasonography (US) to evaluate tumor response to different doses of an agent for antiangiogenic treatment in hepatoma-bearing mice, with histologic measurements of microvascular density (MVD) as the reference standard. Experiments were approved by the regional animal care committee. Mice bearing subcutaneous H22 hepatoma were treated with different doses of thalidomide, 100 mg/kg in group B and 200 mg/kg in group C. Group A (control group) was treated with 0.5% carboxylmethylcellulose. Treatment groups and the control group included 10 mice each. Contrast-enhanced US was used to evaluate the percentage of nonenhanced area, and contrast-enhanced destruction-replenishment US was used to evaluate tumor blood flow. Tumor blood flow was compared with measurements of MVD. Comparisons were made by using one-way analysis of variance and the post hoc least significant difference test for multiple comparisons. Contrast-enhanced gray-scale US showed significant increases in the percentage of nonenhanced area in group C (mean, 10.56% ± 7.25 [standard deviation]), as compared with groups A (mean, 2.40% ± 3.12; P = .004) and B (mean, 3.75% ± 5.55; P = .012). Contrast-enhanced destruction-replenishment US showed significant decreases of tumor blood flow in groups B and C, as compared with group A (P = .003 and P < .001, respectively), and the blood flow in group C was significantly lower than that of group B (P = .01). Immunohistochemical analysis revealed significant decreases of MVD in groups B and C, as compared with MVD in group A (P = .002 and P < .001, respectively); however, there was no significant difference in MVD between groups B and C (P = .21). Quantification of tumor blood flow by using contrast-enhanced destruction-replenishment US shows the potential to guide drug dosage during antiangiogenic therapy.
    Radiology 02/2011; 259(2):406-13. · 6.34 Impact Factor
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    ABSTRACT: To assess the validity of contrast-enhanced ultrasonic parametric perfusion imaging in the evaluation of antiangiogenic tumor treatment by using histology as the reference standard. H22 hepatoma-bearing mice were treated with thalidomide or placebo by intraperitoneal injection. Contrast-enhanced ultrasound was performed on day 8 after bolus injection of SonoVue. Three different parametric perfusion images were calculated based on the following parameters: area under the curve (AUC), maximum intensity (IMAX) and perfusion index (PI). A score from 1 to 5 (1 = low, 5 = excellent) was used for analysis of parametric perfusion images by two independent readers. Immunohistochemical analysis was performed for evaluation of microvascular density (MVD). Treatment with thalidomide resulted in a significant decrease in perfusion scores assigned to AUC, IMAX and PI parametric images as compared with control tumors (P < 0.001). Immunohistochemistry showed significant decreases of MVD in treated tumors as compared with control tumors (P = 0.002). MVD was positively correlated with the perfusion scores assigned to AUC parametric images (r = 0.568, P = 0.009), IMAX parametric images (r = 0.614, P = 0.004) and PI parametric images (r = 0.636, P = 0.003). Contrast-enhanced ultrasonic parametric perfusion imaging provides a noninvasive tool to directly visualize tumor perfusion changes after antiangiogenic tumor treatment.
    European journal of radiology 02/2011; 81(6):1360-5. · 2.65 Impact Factor
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    ABSTRACT: The purpose of this study was to quantify tumor blood perfusion with contrast-enhanced gray-scale ultrasound in the evaluation of tumor response to chemotherapy. Mice bearing H22 hepatoma were treated with cisplatin or placebo by intraperitoneal injection. Contrast-enhanced gray-scale ultrasound was performed on day 8 after bolus injection of a lipid-based ultrasound contrast agent. Regions of interest within the tumor were analyzed offline to determine area under the curve, maximum intensity, perfusion index, mean transit time, time to peak, and quality of fit. Immediately after imaging, mice were euthanized, and tumor tissue was removed for fixation in 10% formalin solution. Microvascular density was measured after anti-CD34 staining. The volume of treated tumors was significantly smaller than that of control tumors (p < 0.001). Treatment with cisplatin resulted in a significant decrease in perfusion index and maximum intensity compared with control tumors (p < 0.05). There were no significant differences between control and treated tumors (p > 0.05) with respect to area under the curve, mean transit time, and time to peak. The microvascular density of treated tumors was significantly lower than that of control tumors (p < 0.001). Quantitative analysis of tumor blood perfusion with contrast-enhanced ultrasound can be used for noninvasive assessment of functional changes in tumors after chemotherapy.
    American Journal of Roentgenology 01/2011; 196(1):W13-7. · 2.90 Impact Factor
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    ABSTRACT: To investigate genes around the locus D4S2964 affected by loss of heterozygosity (LOH) and their clinical implications. Four hundred and forty single nucleotide polymorphisms (SNPs) located at 49 genes around D4S2964 were selected from the National Center for Biotechnology Information website for the SNPs microarray fabrication. LOH of SNPs markers in 112 cases of hepatocellular carcinoma (HCC) tissues and paired adjacent liver tissues were investigated by the SNPs microarray. The correlation between allelic losses with clinicopathological features and overall survival was analyzed. A fine map of LOH of SNPs in genes around D4S2964 was plotted. The average frequency of LOH in genes was 0.39. A correlation between cirrhosis and the FAL index (fractional allelic loss) was found (P = 0.0202). Larger tumor size was found to be significantly associated with LOH in genes ADP-ribosyltransferase 3 (ART3), nucleoporin 54 kDa (NUP54), scavenger receptor class B, member 2 (SCARB2) and coiled-coil domain containing 158 (CCDC158) (P = 0.043, P = 0.019, P = 0.001, P = 0.037, respectively). Kaplan-Meier analysis showed that patients with LOH in ARD1 homolog B (ARD1B) and septin 11 (SEPT11) had a significantly lower survival rate than those with retention (P = 0.021 and P = 0.004, respectively). A Cox regression model suggested that LOH in ARD1B and SEPT11, respectively, were predictors of the overall survival in HCC (P = 0.006 and P = 0.026, respectively). LOH in genes around D4S2964 may play an important role in HCC development and progression. LOH in ARD1B and SEPT11 could serve as novel prognostic predictors in HCC patients.
    World Journal of Gastroenterology 04/2010; 16(16):2046-54. · 2.55 Impact Factor
  • Ultrasound in Medicine and Biology - ULTRASOUND MED BIOL. 01/2009; 35(8).
  • An-Hua Li, Long-Zhong Liu, Wei Zhen, Pei
    Ultrasound in Medicine and Biology - ULTRASOUND MED BIOL. 01/2009; 35(8).