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Is volume rendered image display feasible for three-dimensional ultrasound guidance of interventional radiology procedures?
Abstracts ing system. Differentiation of benign from malignant lesions may require measurements of applied stress or of a strain standard, and refinement of the mechanical model. Future work will investigate these topics, and establish the repeatability of the strain measurements. 32418 Can power Doppler imaging help in acute ankle tendon pathologies? Rawool NM,* Nazarian LN, Radiology (Ultrasound), Thomas Jefferson University Hospital, Philadelphia, PA Objective: The aim of this study was to determine if power Doppler imaging (PDI) can help diagnose the acute nature of ankle tendon pathologies. Methods: Gray-scale and PDI imaging of the ankle was performed in 41 symptomatic patients with one of the commercially available highend ultrasound scanners using a 10 –13 MHz linear transducer. The tendons of the ankle, namely, the Achilles, posterior tibial (PTT), flexor digitorum, peroneus longus, and brevis and anterior tibial (ATT), were examined first on the symptomatic side and then on the contralateral asymptomatic side. The PDI parameters were optimized for each patient’s symptomatic side and then kept constant for the contralateral side. PDI flow if present was confirmed by pulsed Doppler. Results: In the 41 patients, the abnormal tendons detected were as follows: Achilles (11), PTT (28), and ATT (2). The pathologies seen were tendon tears (23), tendinitis (14), and tenosynovitis (4). In tendinitis, the tendon appeared thickened on gray scale, and the involved portion was heterogeneous and hypoechoic. In tendons with tears, the findings were similar to tendinitis, but in addition discontinuity of the tendon fibers were noted. In tenosynovitis, the tendon itself appeared normal, but the sheath around the tendon was thickened and hypoechoic. In all of the above cases increased blood flow on PDI was noted on the symptomatic side. This increased flow was seen within the tendon in cases of tendinitis and tendon tears and along the tendon sheath in cases of tenosynovitis. None of the corresponding contralateral tendons or tendon sheaths showed increased flow. Also, in five cases on the contralateral (asymptomatic) side, an hypoechoic area was noted within the tendon, but no increased flow was noted on PDI, hence confirming the chronic nature of the pathology. Conclusions: PDI imaging can be a complementary tool in diagnosing ankle tendon pathologies. Since on gray-scale imaging, hypoechoic areas can be noted in acute and chronic cases, PDI can help confirm the acute nature of the pathology. 32421 Ultrasound-guided infraclavicular brachial plexus block: Anatomic requisits and comparison with a nerve stimulator device Bargallo X,2 Sala X,3 Carrera A,1 Bianchi L,2 Bru C,2 1. Radiology, Hospital Clinic, Barcelona, Spain, 2. Anesthesia, Hospital Clinic, Barcelona, Spain, and 3. Anatomy, University of Barcelona, Barcelona, Spain Objective: The aim of this study was to show the normal ultrasound anatomy of the brachial plexus (BP) with anatomic correlation and to evaluate the ultrasonography as a guide to block the BP. Methods: Six patients with hand or wrist trauma requiring surgery were included. We selected an infraclavicular approach to block the BP. Ultrasonography was used to guide and place an insulated needle in contact with the target nerve (the lateral cord of the BP in this case). The needle was connected to a nerve stimulator device, which was used to assess muscle contraction (to a maximum of 2 mA) ensuring a good placement of the needle tip.
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Results: In 5 out of 6 patients, the needle placement was optimum obtaining a good muscular contraction. In the other case, a muscular response could not be obtained, and the anesthetic solution was injected under ultrasound guidance. A successful sensory block was obtained in all patients. No complications were observed. Conclusions: We present our preliminary results, which demonstrate ultrasonography is a safe and good method to guide BP block. Although this is a short series, ultrasonography has had good results with a high level of safety. 32426 Endoscopic ultrasonographic diagnosis of gastric adenoma and superficial elevated type of early gastric cancer Kubo M,1 Masuzawa M,2 Kaneko A,1 Nakama A,1 Fujimoto K,2 Hayashi N,3 1. Department of Internal Medicine, NTT West Osaka Hospital, Osaka, Japan, 2. Department.of Internal Medicine, Osaka Police Hospital, Osaka, Japan, and 3. Department of Molecular Therapeutic, Osaka University Graduate School, Osaka, Japan Objective: It is often difficult for endoscopic diagnosis to make a differential diagnosis of gastric adenoma and superficial elevated type of early gastric cancer, when the tumor size is less than 20 mm. Therefore, we performed endoscopic ultrasonographic diagnosis for gastric adenoma and early gastric cancer prior to EMR, compared the ultrasonograms and histological finding of the resected specimens of each lesion, and assessed the usefulness of ultrasonographic histological diagnosis of these lesions. Methods: The ultrasonographic diagnostic systems used for this study were SP501 and SP701 (Fujinon) attached with a cable type probe (20 MHz). Forty patients with biopsy diagnosis of gastric adenoma and 59 patients with biopsy diagnosis of early gastric cancer were enrolled in the study. The endoscopic ultrasonographic imaging diagnosis was carried out 3 weeks after the biopsy when the influence of the biopsy disappeared. Results: The results of ultrasonographic imaging diagnosis for the 99 patients were as follows: among the 40 gastric adenoma patients, gastric adenoma was detected in 19, gastric cancer in 17, and 4 patients were normal; and among the 59 early gastric cancer patients, gastric cancer was detected in 58 and gastric adenoma in 1. All the patients underwent EMR. When the ultrasonographic imaging diagnosis was matched with the histological diagnosis of the resected specimens, both diagnoses corresponded to each other for both diseases. Conclusions: In endoscopic ultrasonographic diagnosis, normal mucosal layer was visualized as two layers, which have different echo levels at 20 MHz. The ultrasonograms of gastric adenoma revealed maintenance of the first layer and the second layer as a lower echo area than the normal lamina propria mucosae. The ultrasonogram of cancer lesion was a rough, low-echo image of higher-brightness than the adenoma, and the first layer disappeared. The above-mentioned findings indicate that the endoscopic ultrasonographic diagnosis is useful for the diagnosis and differential diagnosis of gastric adenoma and superficial elevated type of early gastric cancer. 32435 Is volume rendered image display feasible for three-dimensional ultrasound guidance of interventional radiology procedures? Rose SC,* Nelson TR, Radiology, University of California Medical Center, San Diego, CA Objective: To date, reports of 3D US used for interventional guidance have employed multiplanar reformatted (MPR) image display. If feasible, volume rendered (VR) image display may be more intuitive for the operator. Our goal was to assess the conspicuity of various targets and devices comparing VR display to conventional MPR display.
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Ultrasound in Medicine and Biology
Methods: US phantoms were made using a petroleum gel. Corn starch was used to vary the echotexture. Three phantoms were created with (1) no starch (hypoechoic), (2) 5 ml of starch (isoechoic), or (3) 15 ml of starch (hyperechoic) added. Each phantom had 2-cm diameter hypoechoic, isoechoic, and hyperechoic gel targets imbedded. Implanted devices were a 22-gauge needle and a 14-gauge radiofrequency ablation probe (shaft and tines) introduced into the background gel at 20 and 60 degree inclinations. 3D US volume data sets were acquired. Target and needle conspicuity were judged using a 5-point visual rating scale. The 2D MPR image was held as the reference standard. VR image conspicuity was judged for combinations of 7 different post processing display parameters and compared to MPR images. Results: In only 1 of 9 possible background and target echotexture combinations, and 0 of 56 background and device combinations did VR imaging improve conspicuity compared to MPR. In all other combinations, VR resulted in significant degradation (72–100%) compared to MPR. VR provided diagnostically adequate visualization with regularity (72– 69%) when the target was more echogenic than the background, but less frequently (0 –33%) for all other target and device combinations. The adequacy of VR visualization varied widely depending on the display parameters selected. Conclusions: VR may cause significant degradation of target and device conspicuity compared to MPR that may restrict its ability to guide interventional procedures in some clinical situations. 32439 Analysis of cardiac valve function in neonatal mice using highfrequency ultrasound Lacefield JC,*1,2,5 Spence JR,5 Marlatt NM,3,5 Grant CW,3 Brown A,4,6 1. Electrical and Computer Engineering, University of Western Ontario, London, ON, Canada, 2. Medical Biophysics, University of Western Ontario, London, ON, Canada, 3. Biochemistry, University of Western Ontario, London, ON, Canada, 4. Physiology and Pharmacology, University of Western Ontario, London, ON, Canada, 5. Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada, and 6. Neurodegeneration Research Group, Robarts Research Institute, London, ON, Canada Objective: Methods are developed for high-resolution pulsed Doppler evaluation of cardiac valve function in neonatal mice. These techniques should permit in vivo characterization of valvular defects in murine models for human congenital heart disease. Methods: B-mode ultrasound images and pulsed Doppler data are obtained from anesthetized mice within 24 hours of birth using a 40-MHz ultrasound biomicroscopy system (Model VS40, VisualSonics, Inc.). The animal is mildly restrained on a three-axis micropositioning stage to allow the ultrasound focus to be located precisely and reproducibly. The Doppler sample volume is placed at the left ventricular inflow and aortic outflow tracts while imaging from the parasternal short-axis or parasternal long-axis view. Doppler signals acquired using a 20-kHz pulse repetition frequency are quadrature demodulated and the I and Q waveforms digitized for offline spectral analysis. In our initial study, wild type and EphA3⫺/⫺ mice are examined to verify a suspected disruption in atrioventricular valve development caused by deletion of the EphA3 receptor tyrosine kinase. Qualitative and quantitative evidence of valve defects will be sought by using the digitized Doppler data to detect and estimate mitral regurgitant flow volumes in the knockout animals. Results: Preliminary investigations of neonatal mice demonstrate that a 3-cycle Doppler pulse length (corresponding to a 60-m range gate) resolves flow streams across individual heart valves. However, cardiac anatomical landmarks are less identifiable in B-mode images acquired from neonates compared to images acquired from juvenile mice, so location of the sample volume within the heart must be guided by
Volume 29, Number 5S, 2003 inspection of the Doppler spectrum. This requirement is not expected to restrict the planned measurements. Conclusions: Ultrasound biomicroscopy provides an effective means for assessing intracardiac flow dynamics in neonatal mice despite the small size of the animals (approximately 2 cm and 1–1.5 g). The qualities that position ultrasound as the primary technology for clinical cardiac imaging are equally evident in micro-imaging applications like the study described here. 32441 The use of angle correction in assessment of the peak systolic velocity of the fetal middle cerebral artery Abel DE,*1 Grambow SC,2 Brancazaio LR,1 Hertzberg BS,3 Hall KA,3 McNally PJ,3 Moore N,3 Pelton JE,3 1. Maternal-Fetal Medicine, Duke University Medical Center, Durham, NC, 2. Biostatistics, Duke University Medical Center, Durham, NC, and 3. Radiology, Duke University Medical Center, Durham, NC Objective: The peak systolic velocity (PSV) of the fetal middle cerebral artery (MCA) as measured by Doppler ultrasonography has been studied as a technique by which more invasive procedures may be avoided in the isoimmunized patient. The objective of this study was to assess the ability to obtain a zero degree angle of insonation at four different locations. Methods: This study was performed on 143 normal fetuses. PSV measurements were assessed at the central portion of the vessel closest to its origin from the internal carotid artery as well as the most peripheral portion. The MCA proximal to the transducer was compared with the distal MCA for a total of four locations per fetus. For each of the four locations, angle corrected PSV measurements were collected if the angle of insonation was not at 0 degrees. The percentage of PSV measurements at each site that required angle correction was then calculated. Data were analyzed using linear mixed models. Where appropriate, p-values were adjusted for multiple comparisons using the Tukey procedure. Results: Gestational age ranged from 16.1 to 41 weeks (mean ⫽ 26.8 weeks). The four sites, proximal central (PC), proximal peripheral (PP), distal central (DC), and distal peripheral (DP) were compared. The percentage of PSV measurements requiring angle correction was the following: PC ⫽ 90/129 (69.8%), PP ⫽ 87/125 (69.6%), DC ⫽ 85/120 (70.8%), DP ⫽ 82/116 (70.7%). For each site, the average angle needed for correction was as follows (mean ⫾ SE): PC ⫽ 19.8 ⫾ 1.1°, PP ⫽ 23.3 ⫾ 1.1°, DC ⫽ 17.4 ⫾ 1.1°, DP ⫽ 17.3 ⫾ 1.2° (F statistic ⫽ 6.13, P ⫽ .0005). Significant differences were noted between UP and DC (P ⫽ .0017) and UP and DP (P ⫽ .0013). Conclusions: The proximal peripheral site required the least amount of angle correction. In addition, this site may require the greatest angle if indeed angle correction is needed. The role of angle correction in the assessment of PSV at different MCA locations warrants further investigation in fetuses at risk. 32442 Clinical and ultrasonographic correlation in cutaneous localized scleroderma Bouer M,*1 Messina MC,2 Oliveira IR,1 1. Radiologia, Hospital das Clı´nicas da FMUSP, Sa˜ o Paulo, Brazil, and 2. Dermatologia, Hospital das Clı´nicas da FMUSP, Sa˜ o Paulo, Brazil Objective: The aim of this study was to describe the ultrasonographic findings in localized scleroderma and correlation with the clinical aspect. Methods: 12 patients presenting localized scleroderma lesions with clinical and anatomo-pathological diagnostic were submitted to ultrasonographic examinations with an equipment GE LOGIQ 700 using a
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Results: In 5 out of 6 patients, the needle placement was optimum obtaining a good muscular contraction. In the other case, a muscular response could not be obtained, and the anesthetic solution was injected under ultrasound guidance. A successful sensory block was obtained in all patients. No complications were observed. Conclusions: We present our preliminary results, which demonstrate ultrasonography is a safe and good method to guide BP block. Although this is a short series, ultrasonography has had good results with a high level of safety. 32426 Endoscopic ultrasonographic diagnosis of gastric adenoma and superficial elevated type of early gastric cancer Kubo M,1 Masuzawa M,2 Kaneko A,1 Nakama A,1 Fujimoto K,2 Hayashi N,3 1. Department of Internal Medicine, NTT West Osaka Hospital, Osaka, Japan, 2. Department.of Internal Medicine, Osaka Police Hospital, Osaka, Japan, and 3. Department of Molecular Therapeutic, Osaka University Graduate School, Osaka, Japan Objective: It is often difficult for endoscopic diagnosis to make a differential diagnosis of gastric adenoma and superficial elevated type of early gastric cancer, when the tumor size is less than 20 mm. Therefore, we performed endoscopic ultrasonographic diagnosis for gastric adenoma and early gastric cancer prior to EMR, compared the ultrasonograms and histological finding of the resected specimens of each lesion, and assessed the usefulness of ultrasonographic histological diagnosis of these lesions. Methods: The ultrasonographic diagnostic systems used for this study were SP501 and SP701 (Fujinon) attached with a cable type probe (20 MHz). Forty patients with biopsy diagnosis of gastric adenoma and 59 patients with biopsy diagnosis of early gastric cancer were enrolled in the study. The endoscopic ultrasonographic imaging diagnosis was carried out 3 weeks after the biopsy when the influence of the biopsy disappeared. Results: The results of ultrasonographic imaging diagnosis for the 99 patients were as follows: among the 40 gastric adenoma patients, gastric adenoma was detected in 19, gastric cancer in 17, and 4 patients were normal; and among the 59 early gastric cancer patients, gastric cancer was detected in 58 and gastric adenoma in 1. All the patients underwent EMR. When the ultrasonographic imaging diagnosis was matched with the histological diagnosis of the resected specimens, both diagnoses corresponded to each other for both diseases. Conclusions: In endoscopic ultrasonographic diagnosis, normal mucosal layer was visualized as two layers, which have different echo levels at 20 MHz. The ultrasonograms of gastric adenoma revealed maintenance of the first layer and the second layer as a lower echo area than the normal lamina propria mucosae. The ultrasonogram of cancer lesion was a rough, low-echo image of higher-brightness than the adenoma, and the first layer disappeared. The above-mentioned findings indicate that the endoscopic ultrasonographic diagnosis is useful for the diagnosis and differential diagnosis of gastric adenoma and superficial elevated type of early gastric cancer. 32435 Is volume rendered image display feasible for three-dimensional ultrasound guidance of interventional radiology procedures? Rose SC,* Nelson TR, Radiology, University of California Medical Center, San Diego, CA Objective: To date, reports of 3D US used for interventional guidance have employed multiplanar reformatted (MPR) image display. If feasible, volume rendered (VR) image display may be more intuitive for the operator. Our goal was to assess the conspicuity of various targets and devices comparing VR display to conventional MPR display.
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Ultrasound in Medicine and Biology
Methods: US phantoms were made using a petroleum gel. Corn starch was used to vary the echotexture. Three phantoms were created with (1) no starch (hypoechoic), (2) 5 ml of starch (isoechoic), or (3) 15 ml of starch (hyperechoic) added. Each phantom had 2-cm diameter hypoechoic, isoechoic, and hyperechoic gel targets imbedded. Implanted devices were a 22-gauge needle and a 14-gauge radiofrequency ablation probe (shaft and tines) introduced into the background gel at 20 and 60 degree inclinations. 3D US volume data sets were acquired. Target and needle conspicuity were judged using a 5-point visual rating scale. The 2D MPR image was held as the reference standard. VR image conspicuity was judged for combinations of 7 different post processing display parameters and compared to MPR images. Results: In only 1 of 9 possible background and target echotexture combinations, and 0 of 56 background and device combinations did VR imaging improve conspicuity compared to MPR. In all other combinations, VR resulted in significant degradation (72–100%) compared to MPR. VR provided diagnostically adequate visualization with regularity (72– 69%) when the target was more echogenic than the background, but less frequently (0 –33%) for all other target and device combinations. The adequacy of VR visualization varied widely depending on the display parameters selected. Conclusions: VR may cause significant degradation of target and device conspicuity compared to MPR that may restrict its ability to guide interventional procedures in some clinical situations. 32439 Analysis of cardiac valve function in neonatal mice using highfrequency ultrasound Lacefield JC,*1,2,5 Spence JR,5 Marlatt NM,3,5 Grant CW,3 Brown A,4,6 1. Electrical and Computer Engineering, University of Western Ontario, London, ON, Canada, 2. Medical Biophysics, University of Western Ontario, London, ON, Canada, 3. Biochemistry, University of Western Ontario, London, ON, Canada, 4. Physiology and Pharmacology, University of Western Ontario, London, ON, Canada, 5. Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada, and 6. Neurodegeneration Research Group, Robarts Research Institute, London, ON, Canada Objective: Methods are developed for high-resolution pulsed Doppler evaluation of cardiac valve function in neonatal mice. These techniques should permit in vivo characterization of valvular defects in murine models for human congenital heart disease. Methods: B-mode ultrasound images and pulsed Doppler data are obtained from anesthetized mice within 24 hours of birth using a 40-MHz ultrasound biomicroscopy system (Model VS40, VisualSonics, Inc.). The animal is mildly restrained on a three-axis micropositioning stage to allow the ultrasound focus to be located precisely and reproducibly. The Doppler sample volume is placed at the left ventricular inflow and aortic outflow tracts while imaging from the parasternal short-axis or parasternal long-axis view. Doppler signals acquired using a 20-kHz pulse repetition frequency are quadrature demodulated and the I and Q waveforms digitized for offline spectral analysis. In our initial study, wild type and EphA3⫺/⫺ mice are examined to verify a suspected disruption in atrioventricular valve development caused by deletion of the EphA3 receptor tyrosine kinase. Qualitative and quantitative evidence of valve defects will be sought by using the digitized Doppler data to detect and estimate mitral regurgitant flow volumes in the knockout animals. Results: Preliminary investigations of neonatal mice demonstrate that a 3-cycle Doppler pulse length (corresponding to a 60-m range gate) resolves flow streams across individual heart valves. However, cardiac anatomical landmarks are less identifiable in B-mode images acquired from neonates compared to images acquired from juvenile mice, so location of the sample volume within the heart must be guided by
Volume 29, Number 5S, 2003 inspection of the Doppler spectrum. This requirement is not expected to restrict the planned measurements. Conclusions: Ultrasound biomicroscopy provides an effective means for assessing intracardiac flow dynamics in neonatal mice despite the small size of the animals (approximately 2 cm and 1–1.5 g). The qualities that position ultrasound as the primary technology for clinical cardiac imaging are equally evident in micro-imaging applications like the study described here. 32441 The use of angle correction in assessment of the peak systolic velocity of the fetal middle cerebral artery Abel DE,*1 Grambow SC,2 Brancazaio LR,1 Hertzberg BS,3 Hall KA,3 McNally PJ,3 Moore N,3 Pelton JE,3 1. Maternal-Fetal Medicine, Duke University Medical Center, Durham, NC, 2. Biostatistics, Duke University Medical Center, Durham, NC, and 3. Radiology, Duke University Medical Center, Durham, NC Objective: The peak systolic velocity (PSV) of the fetal middle cerebral artery (MCA) as measured by Doppler ultrasonography has been studied as a technique by which more invasive procedures may be avoided in the isoimmunized patient. The objective of this study was to assess the ability to obtain a zero degree angle of insonation at four different locations. Methods: This study was performed on 143 normal fetuses. PSV measurements were assessed at the central portion of the vessel closest to its origin from the internal carotid artery as well as the most peripheral portion. The MCA proximal to the transducer was compared with the distal MCA for a total of four locations per fetus. For each of the four locations, angle corrected PSV measurements were collected if the angle of insonation was not at 0 degrees. The percentage of PSV measurements at each site that required angle correction was then calculated. Data were analyzed using linear mixed models. Where appropriate, p-values were adjusted for multiple comparisons using the Tukey procedure. Results: Gestational age ranged from 16.1 to 41 weeks (mean ⫽ 26.8 weeks). The four sites, proximal central (PC), proximal peripheral (PP), distal central (DC), and distal peripheral (DP) were compared. The percentage of PSV measurements requiring angle correction was the following: PC ⫽ 90/129 (69.8%), PP ⫽ 87/125 (69.6%), DC ⫽ 85/120 (70.8%), DP ⫽ 82/116 (70.7%). For each site, the average angle needed for correction was as follows (mean ⫾ SE): PC ⫽ 19.8 ⫾ 1.1°, PP ⫽ 23.3 ⫾ 1.1°, DC ⫽ 17.4 ⫾ 1.1°, DP ⫽ 17.3 ⫾ 1.2° (F statistic ⫽ 6.13, P ⫽ .0005). Significant differences were noted between UP and DC (P ⫽ .0017) and UP and DP (P ⫽ .0013). Conclusions: The proximal peripheral site required the least amount of angle correction. In addition, this site may require the greatest angle if indeed angle correction is needed. The role of angle correction in the assessment of PSV at different MCA locations warrants further investigation in fetuses at risk. 32442 Clinical and ultrasonographic correlation in cutaneous localized scleroderma Bouer M,*1 Messina MC,2 Oliveira IR,1 1. Radiologia, Hospital das Clı´nicas da FMUSP, Sa˜ o Paulo, Brazil, and 2. Dermatologia, Hospital das Clı´nicas da FMUSP, Sa˜ o Paulo, Brazil Objective: The aim of this study was to describe the ultrasonographic findings in localized scleroderma and correlation with the clinical aspect. Methods: 12 patients presenting localized scleroderma lesions with clinical and anatomo-pathological diagnostic were submitted to ultrasonographic examinations with an equipment GE LOGIQ 700 using a