Correlations between the Various Methods of Estimating Prostate Volume: Transabdominal, Transrectal, and Three-Dimensional US

OBJECTIVE: To evaluate the correlations between prostate volumes estimated by transabdominal, transrectal, and three-dimensional US and the factors affecting the differences. MATERIALS AND METHODS: The prostate volumes of 94 consecutive patients were measured by both transabdominal and transrectal US. Next, the prostate volumes of 58 other patients was measured by both transrectal and three-dimensional US. We evaluated the degree of correlation and mean difference in each comparison. We also analyzed possible factors affecting the differences, such as the experiences of examiners in transrectal US, bladder volume, and prostate volume. RESULTS: In the comparison of transabdominal and transrectal US methods, the mean difference was 8.4 +/- 10.5 mL and correlation coefficient (r) was 0.775 (p 0.05). The comparison between the transrectal and three-dimensional US methods revealed a mean difference of 3.7 +/- 3.4 mL and the correlation coefficient was 0.924 for the experienced examiner. Furthermore, no significant difference existed between examiners (p > 0.05). Prostate volume measured by transrectal US showed a positive correlation with the difference for the beginner only (r = 0.405, p < 0.05). CONCLUSION: In the prostate volume estimation by US, experience in transrectal US is important in the correlation with transabdominal US, but not with three-dimensional US. Also, less experienced examiners' assessment of the prostate volume can be affected by prostate volume itself.

Utility of Vascular Enhancement Technique (ClarifyTM) in Ultrasonographic Evaluation of Abdominal Vessels

PURPOSE: Vascular enhancement (VE) technology(ClarifyTM) is a new technique in vascular, B-mode imaging. The purpose of this study was to evaluate the value of VE technology in ultrasonographic diagnosis of abdominal vasculature. MATERIALS and METHODS: Seventy-one adult patients (39 men and 32 women; age range, 25-89 years; mean age, 56 years) who had undergone abdominal ultrasonography were included in this study. The imaging was performed with a 1.8-4.0 MHz convex array transducer (SONOLINE, Antares, Siemens Medical Solutions, WA) by an abdominal radiologist. The radiologist obtained images of the same vascular area with each of conventional ultrasonography imaging (CUS), tissue harmonic imaging (THI), CUS plus VE technique and THI plus VE technique. Images were divided into normal (56) and abnormal (15) groups. The vessel visibility, conspicuity of the vascular wall and contrast resolution with adjacent structures were evaluated in the normal group, and the lesion conspicuity and border sharpness were evaluated in the abnormal group. On the PACS monitor, the images were graded into four grades by two radiologists in consensus. Statistical analysis was performed using Wilcoxon signed rank test. RESULTS: In the normal group, all parameters of the ultrasonographic imaging which applied the VE technique were superior to those of the imaging without VE technique (p < 0.05). In the abnormal group, combined use of VE technique with CUS or THI provided better results than CUS or THI alone in terms of lesion conspicuity and border sharpness (p < 0.05). THI combined with VE technique provided the best image quality among the 4 ultrasonographic methods examined in this study for the evaluation of both normal and abnormal abdominal vessels (p < 0.05). CONCLUSION: VE technology was a helpful technique to evaluate the abdominal vasculature. Furthermore, VE technique combined with THI provided better image quality than other ultrasonographic methods in the evaluation of abdominal vessels.

Sonographic Evaluation of Breast Nodules: Comparison of Conventional, Real-Time Compound, and Pulse-Inversion Harmonic Images

OBJECTICE: To compare the use of conventional, real-time compound, and pulse-inversion harmonic imaging in the evaluation of breast nodules. MATERIALS AND METHODS: Fifty-two breast nodules were included in this study, conducted between May and December 2000, in which conventional, real-time compound, and pulse-inversion harmonic images were obtained in the same plane. Three radiologists, each blinded to the interpretations of the other two, evaluated the findings, characterizing the lesions and ranking the three techniques from grade 1, the worst, to grade 3, the best. Lesion conspicuity was assessed, and lesions were also characterized in terms of their margin, clarity of internal echotexture, and clarity of posterior echo pattern. The three techniques were compared using Friedman's test, and interobserver agreement in image interpretation was assessed by means of the intraclass correlation coefficient. RESULTS: With regard to lesion conspicuity, margin, and internal echotexture of the nodules, real-time compound imaging was the best technique (p < 0.05); in terms of posterior echo pattern, the best was pulse-inversion harmonic imaging (p < 0.05). Real-time compound and pulse inversion harmonic imaging were better than conventional sonography in all evaluative aspects. Interobserver agreement was greater than moderate. CONCLUSION: Real-time compound and pulse-inversion harmonic imaging procedures are superior to conventional sonography in terms of both lesion conspicuity and the further characterization of breast nodules. Real-time compound imaging is the best technique for evaluation of the margin and internal echotexture of nodules, while pulse-inversion harmonic imaging is very effective for the evaluation of the posterior echo patterns.

The Usefulness of Pulsatile Flow Detection in Measuring Resistive Index in Renal Doppler US

OBJECTIVE: To assess the usefulness of pulsatile flow detection (PFD), a newly developed function of color Doppler US, in measuring resistive index (RI) in renal Doppler US and to compare it with conventional color Doppler (CCD). MATERIALS AND METHODS: Fifty-six kidneys in 31 patients were randomly selected and divided into two groups. In group A, RI was measured first with the aid of CCD, and then with PFD. In group B, data were obtained in the reverse order. The time required for each RI measurement was recorded in seconds. The quality of the Doppler spectral waveform was subjectively graded as 0, 1, or 2 and examination time and waveform quality were compared between PFD and CCD. RESULTS: The time required to measure RI with PFD (PFD time) was less than with CCD (CCD time) (mean 42.7 secs vs. mean 70.3 secs; p = 0.031). There was no significant difference in PFD time between group A and B, but CCD time was shorter in group B (70.3 secs vs. 24.6 secs; p = 0.0004). Spectral waveform quality was not significantly different between PFD and CCD. CONCLUSION: The time required to measure RI in kidneys can be shortened with the aid of the PFD function in color Doppler US without affecting the quality of the examination.

Does Real-time Compound Imaging Improve Evaluation of Breast Cancer Compared to Conventional Sonography? / 한국유방암학회지

PURPOSE: Real-time compound imaging obtains multiple coplanar tomographic ultrasound images and combines them into a single compound image, reducing acoustic artifacts and noise. The purpose of this study is to determine if real-time compound imaging improves evaluation of breast cancer compared to conventional sonography. METHODS: From May 2000 to July 2001, we scanned the same axial plane with conventional sonography and real-time compound imaging in 520 patients with solid breast nodules. Twenty-eight cancers in 25 patients which were confirmed pathologically were included in this study. Twenty-five of 28 cases were invasive ductal carcinoma and the remaining three were ductal carcinoma in situ. Each image pair consisted of a conventional ultrasound and a real-time compound image with a stationary probe, to maintain an identical projection. The evaluating points were 1) contrast between cancer and normal breast tissue, 2) depiction of margin, 3) clarity of internal echotexture, 4) clarity of posterior echo pattern, and 5) clarity of internal microcalcifi-cation. Two radiologists graded for quality of images on a 5-point scale and in a blinded fashion and Wilcoxon rank test was used for comparison between conventional and real-time compound images. RESULTS: For reviewer 1/reviewer 2, compound image showed grade improvements in 1) contrast (1.4?0.5/1.4?0.7), 2) margin (1.4?0.5/1.8?0.4), 3) internal echotexture (1.0?0.5/1.4?0.7), 4) posterior echo pattern (?0.9?0.7/?0.8?0.7), and 5) internal microcalcification (1.8?0.5/1.8?0.5). In all evaluating points, there was statistically significant difference between conventional and compound images (P<0.05). CONCLUSION: Real-time compound imaging improves contrast, depiction of margin, and clarity of internal echotexture and internal microcalcification of the breast cancer. But compound image is not effective to evaluate posterior echo pattern of the breast cancer.

Ultrasonographic Evaluation of Focal Hepatic Lesions : Comparison of Fundamental, Tissue Harmonic, Fundamental Compound and Harmonic Compound Imaging Techniques

PURPOSE: To compare the ultrasonographic image quality of fundamental imaging (FI), tissue harmonic imaging (THI), fundamental compound imaging (FCI), and harmonic compound imaging (HCI) in the evaluation of focal hepatic lesions. MATERIALS AND METHODS: Ninety-four focal hepatic lesions (27 hemangiomas, 15 hepatocellular carcinomas, 14 metastases, and 38 cysts) in 74 patients [30 males and 44 females aged 33-82 (mean, 55) years] were included in our study. All patients underwent FI, THI, FCI, and HCI using an HDI 5000 Sono CT scanner (Advanced Technology Laboratories, Bothell, CA., U.S.A.) with a 2-5MHz convex transducer. Images were analysed by two abdominal radiologists who used a 4-point scale and reached a consensus. In the case of solid lesions, four parameters, as follows, were evaluated: lesion conspicuity, internal morphology, overall image quality, and peripheral halo. For cysts, three parameters (internal artifact, sharpness of margin, and posterior enhancement) were assessed. For statistical analysis, the Scheffe method (ANOVA test) was used. RESULTS: For solid lesions (hemangioma, hepatocellular carcinoma, and metastasis), THI, FCI and HCI were superior to FI in terms of lesion conspicuity, internal morphology and overall image quality (p<0.05), though for peripheral halo, the four imaging techniques were not statistically different. For cysts, THI, FCI and HCI revealed clearer internal artifact and better margin sharpness than FI (p<0.05), while in terms of posterior enhancement, THI was superior to both FI and FCI, and HCI was superior to FCI (p<0.05). CONCLUSION: For the evaluation of focal hepatic lesions, harmonic imaging techniques (i.e. THI and HCI) appear to provide better image quality than fundamental imaging techniques (i.e. FI and FCI). There is, however no significant difference in image quality between the two harmonic techniques.

Prostate Volume Measurement by TRUS Using Heights Obtained by Transaxial and Midsagittal Scanning : Comparison with Specimen Volume Following Radical Prostatectomy

OBJECTIVE: The purpose of this study was to determine, when measuring prostate volume by TRUS, whether height is more accurately determined by transaxial or midsagittal scanning. MATERIALS AND METHODS: Sixteen patients who between March 1995 and March 1998 underwent both preoperative TRUS and radical prostatectomy for prostate cancer were included in this study. Using prolate ellipse volume calculation (height x length x width x pi/6), TRUS prostate volume was determined, and was compared with the measured volume of the specimen. RESULTS: Prostate volume measured by TRUS, regardless of whether height was determined transaxially or midsagittally, correlated closely with real specimen volume. When height was measured in one of these planes, a paired t test revealed no significant difference between TRUS prostate volume and real specimen volume (p = .411 and p = .740, respectively), nor were there significant differences between the findings of transaxial and midsagittal scanning (p = .570). A paired sample test, however, indicated that TRUS prostate volumes determined transaxially showed a higher correlation coefficient (0.833) and a lower standard deviation (9.04) than those determined midsagittally (0.714 and 11.48, respectively). CONCLUSION: Prostate volume measured by TRUS closely correlates with real prostate volume. Furthermore, we suggest that when measuring prostate volume in this way, height is more accurately determined by transaxial than by midsagittal scanning.

Prostate Volume Measurement by TRUS Using Heights Obtained by Transaxial and Midsagittal Scanning : Comparison with Specimen Volume Following Radical Prostatectomy

OBJECTIVE: The purpose of this study was to determine, when measuring prostate volume by TRUS, whether height is more accurately determined by transaxial or midsagittal scanning. MATERIALS AND METHODS: Sixteen patients who between March 1995 and March 1998 underwent both preoperative TRUS and radical prostatectomy for prostate cancer were included in this study. Using prolate ellipse volume calculation (height x length x width x pi/6), TRUS prostate volume was determined, and was compared with the measured volume of the specimen. RESULTS: Prostate volume measured by TRUS, regardless of whether height was determined transaxially or midsagittally, correlated closely with real specimen volume. When height was measured in one of these planes, a paired t test revealed no significant difference between TRUS prostate volume and real specimen volume (p = .411 and p = .740, respectively), nor were there significant differences between the findings of transaxial and midsagittal scanning (p = .570). A paired sample test, however, indicated that TRUS prostate volumes determined transaxially showed a higher correlation coefficient (0.833) and a lower standard deviation (9.04) than those determined midsagittally (0.714 and 11.48, respectively). CONCLUSION: Prostate volume measured by TRUS closely correlates with real prostate volume. Furthermore, we suggest that when measuring prostate volume in this way, height is more accurately determined by transaxial than by midsagittal scanning.

Three-Dimensional Power Doppler Imaging

Three-dimensional (3-D) ultrasonographic imaging techniques have recently shown rapid development and theirclinical application has begun to attract considerable at-tention. Power Doppler sonography is known to be moresensitive than color Doppler for detecting blood flow, and there is also less noise and clutter. This paperdescribes the basic principles and initial clinical experience of 3-D power Doppler sonography.

Endoanal Ultrasound in Benign Anal Disorders: Findings and Usefulness

PURPOSE: To evaluate the usefulness of endoanal ultrasonography and to determine the imaging features of patients with fecal incontinence, anal abscess or anal fistula. MATERIALS AND METHODS: Twenty five patients underwent endoanal ultrasonography between October 1995 and July 1996. Ten of these were fecal incontinence cases, eight had an anal abscess, and seven, an anal fistula. The incontinence grading scale (IGS) was used for clinical grading of fecal incontinence and pudendal nerve terminal motor latency (PNTML) for pudendal nerve injury. Endoanal ultrasonographic features and operative findings were retrospectively reviewed. RESULTS: Endoanal ultrasonography revealed defective sphincteric muscles in all three patients with myogenic fecal incontinence, but in six of seven cases with neurogenic fecal incontinence, these muscles were not defective. Myogenic and neurogenic incontience showed different findings (p=0.033). In comparison with surgical findings, endoanal ultrasonography was 88% accurate in anal abscess cases and 86% accurate in those of anal fistula. CONCLUSION: Endoanal ultrasonography in conjunction with PNTML was very useful for the detection of the site and severity of sphincteric muscle defect and diagnosis of the etiology of fecal incontinence. Through analysis of the site and type of lesion, the procedure can also serve as a guide to the surgical treatment of patients with anal abscess or fistula.