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Head and neck computed tomography virtual endoscopy: Evaluation of a new imaging technique

LARYNGOSCOPE 1999年第10期109卷 1570-1579页

作者： Gallivan, RP Nguyen, TH Armstrong, WB Univ Calif Irvine Med Ctr Dept Otolaryngol Head & Neck Surg Orange CA 92868 USA Univ Calif Irvine Dept Radiol Irvine CA 92717 USA Vet Affairs Med Ctr Dept Radiol Long Beach CA USA Vet Affairs Med Ctr Dept Surg Long Beach CA USA

Objective: To evaluate a new radiographic imaging technique: computed tomography virtual endoscopy (CTVE) for head and neck tumors. Study Design: Twenty-one patients presenting with head and neck masses who underwent axial computed tomography (CT) scan with contrast were evaluated by CTVE, Comparisons were made with video-recorded images and operative records to evaluate the potential utility of this new imaging technique, Methods: Twenty-one patients with aerodigestive head and neck tumors were evaluated by CTVE, One patient had a nasal cylindrical cell papilloma;the remainder, squamous cell carcinomas distributed throughout the upper aerodigestive tract. Patients underwent complete head and neck examination, flexible laryngoscopy, axial CT with contrast, CTVE, and in most cases, operative endoscopy, Available clinical and radiographic evaluations were compared and correlated to CTVE findings. Results: CTVE accurately demonstrated abnormalities caused by intraluminal tumor, but where there was apposition of normal tissue against tumor, inaccurate depictions of surface contour occurred. Contour resolution was limited, and mucosal irregularity could not be de fined. There was very good overall correlation between virtual images, flexible laryngoscopic findings, rigid endoscopy, and operative evaluation in cases where oncological resections were performed. CTVE appears to be most accurate in evaluation of subglottic and nasopharyngeal anatomy in our series of patients, Conclusion CTVE: is a new radiographic technique that provides surface-contour details, The technique is undergoing rapid technical evolution, and although the image quality is limited in situations where there is apposition of tissue folds, there are a number of potential applications for this new imaging technique.

关键词： computer-assisted image processing head and neck virtual endoscopy x-ray-computed tomography

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image analysis of benign and malignant neck masses

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ANNALS OF OTOLOGY RHINOLOGY AND LARYNGOLOGY 1998年第8期107卷 689-696页

作者： Plant, RL Eastern Virginia Med Sch Dept Otolaryngol Head & Neck Surg Norfolk VA 23507 USA

Current techniques for differentiating benign and malignant neck masses in computed tomography scans rely on basic features such as size and image density. Advances in digital imaging have led to development of sophisticated computerized image processing tools. Four different image processing algorithms were used to compare 10 patients with neck masses positive for squamous cell carcinoma and 11 patients with benign neck nodes. Statistically significant differences were seen between the malignant and benign masses for edge analysis and Fourier analysis. Significant differences were also seen in several texture parameters, although these results were considered less reliable. There were no differences between the two groups when compared by histogram analysis. It is concluded that both edge analysis and Fourier analysis can provide additional information to distinguish benign and malignant neck masses.

关键词： computer-assisted image processing head and neck neoplasms

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Rectal imaging and cancer

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SEMINARS IN SURGICAL ONCOLOGY 1998年第2期15卷 72-77页

作者： Vining, DJ Wake Forest Univ Bowman Gray Sch Med Dept Radiol Winston Salem NC 27157 USA

Rectal imaging has evolved substantially during the past 25 years and now offers surgeons exquisite anatomic detail and physiologic information. Dynamic cystoproctography, helical computed tomography, endoscopic ultrasonography, endorectal magnetic resonance imaging, and immunoscintigraphy have become standards for the diagnosis of rectal disease, staging of neoplasia, and survey of therapeutic results. The indications, limitations, anal relative costs of current imaging methods are reviewed, and advances in imaging technology that promise future benefits to colorectal surgeons are introduced. Semin. Surg. Oncol. 15:72-77, 1998. (C) 1998 Wiley-Liss, Inc.

关键词： rectal neoplasms colorectal neoplasms pelvic floor radiography diagnostic imaging X-ray computed tomography colonoscopy angiography ultrasonography endoscopy magnetic resonance imaging sensitivity and specificity computer-assisted image processing radioimmunodetection emission-computed tomography single-photon emission-computed tomography defecation lymph node metastasis neoplasm staging local neoplasm recurrence trends barium sulfate enema cost-benefit analysis

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A symbolic environment for visualizing activated foci in functional neuroimaging datasets

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Medical image Analysis 1998年第3期2卷 215-226页

作者： Rehm, Kelly Lakshminaryan, Kamakshi Frutiger, Sally Schaper, Kirt A. De Sumners, Witt Strother, Stephen C. Anderson, Jon R. Rottenberg, David A. PET Imaging Center Vet. Administration Medical Center Minneapolis MN United States Department of Radiology University of Minnesota Minneapolis MN United States Department of Neurology University of Minnesota Minneapolis MN United States Department of Mathematics Florida State University Tallahassee FL United States

This paper presents a symbolic visualization environment known as the Corner Cube environment, which was developed to facilitate rapid examination and comparison of activated foci defined by analyses of functional neuroimaging datasets. We have performed a comparative evaluation of this environment against maximum-intensity projection and 'gallery of slices' displays, and the results suggest that the Corner Cube environment has definite advantages over both conventional display techniques. We conclude that the Corner Cube is an effective tool for summarizing the spatial characteristics of activated foci within an easily understood visual context and is especially useful for displaying the similarities and differences in functional neuroimaging datasets.

关键词： Brain mapping computer graphics computer-assisted image processing Emission-computed tomography Observer performance experiment Statistical models

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Comparison of B-mode, M-mode and echo-tracking methods for measurement of the arterial distension waveform

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ULTRASOUND IN MEDICINE AND BIOLOGY 1997年第6期23卷 879-887页

作者： Stadler, RW Taylor, JA Lees, RS BOSTON HEART FDN CAMBRIDGEMA 02142 HARVARD UNIV MITDIV HLTH SCI & TECHNOLCAMBRIDGEMA 02142 HARVARD UNIV SCH MEDDIV AGINGBOSTONMA 02142 BETH ISRAEL HOSP HEBREW REHABIL CTR AGEDBOSTONMA 02142

Measurements of arterial diameter throughout the cardiac cycle (i.e., the arterial distension waveform) are conducted increasingly to study mechanical properties of the arterial wall and changes associated with disease. The distension waveform of peripheral arteries can be measured noninvasively via ultrasonic echo tracking, M-mode imaging, and B-mode imaging, Of these, echo tracking is the most popular method because of its single micrometer resolution during continuous measurements under ideal conditions, However, high resolution within continuous measurements does not imply high reproducibility between measurements. Therefore, we compared repeated measurements of the amplitude of common carotid artery distension in 26 subjects, obtained sequentially in random order by: 1. Off-line echo tracking of digitized radiofrequency ultrasound;2. M-mode imaging with automated edge detection;and 3. 30-Hz B-mode imaging with automated edge detection and model-based diameter estimation. In each case, the transducer was hand-held and was removed from the neck between repeated measurements. The amplitude of arterial distension was estimated from the serial diameter measurements by maximum likelihood (ML) estimation, by least-squares fit of a Fourier series model, and by application of a cubic smoothing spline. Within continuous measurements, the standard deviation of the ML distension amplitude for neighboring cardiac cycles was significantly smaller (p < 0.05) with echo-tracking (0.023 mm) than with the B-mode (0.036 mm) or M-mode (0.074 mm) methods. However, between discontinuous measurements on the same subject, the standard deviation of the ML distension amplitude was similar for the echo-tracking (0.076 mm) and B-mode (0.073 mm) methods. The Fourier series model and the cubic smoothing spline slightly reduced the standard deviation of the B-mode and M-mode distension amplitudes, but also reduced the mean amplitude estimate. On the basis of this relative comparison of method

关键词： ultrasound ultrasonic echo tracking computer-assisted image processing arterial distensibility arterial diameter

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A novel technique for mapping the lipid composition of atherosclerotic fatty streaks by en face fluorescence microscopy

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JOURNAL OF HISTOCHEMISTRY & CYTOCHEMISTRY 1997年第5期45卷 743-753页

作者： Klinkner, AM Bugelski, PJ Waites, CR Louden, C Hart, TK Kerns, WD UNIV PENN SCH VET MEDDEPT PATHOBIOLPHILADELPHIAPA 19104

We introduce here a new fluorescence microscopy technique for en face analysis of the atherosclerotic fatty streaks (FS). This technique is semiquantitative and has the sensitivity and resolution to map lipids to individual cells in FS less than 100 mu m in diameter. New Zealand White rabbits were fed an atherogenic diet for up to 26 weeks. Aortas were fixed in formalin and stained en bloc with the fluorescent dyes Nile red and filipin. Fluorescent staining was validated by correlating microfluorimetric and biochemical measurements of the lipid content in FS. To determine the cell types associated with the different staining patterns, FS were also evaluated by transmission electron microscopy (TEM) and immunohistochemistry (IH). Correlation of microfluorimetry, TEM, IH, and biochemical data indicated that regions rich in non-esterified cholesterol stained with filipin and fluoresced blue owing to accumulations of lipid vessicles and/or cholesterol crystals. Regions rich in neutral and polar lipids stained with Nile red and fluoresced yellow or orange, respectively, owing to accumulations of lipids in both macrophages and smooth muscle cells (SMC). Digital overlays of the filipin and Nile red images revealed that larger lesions (>0.5 mm diameter) had a ''nested'' distribution of lipids, with a blue (filipin) fringe surrounding an orange (Nile red) fringe surrounding a yellow (Nile red) center.

关键词： filipin Nile red computer-assisted image processing

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Spiral CT angiography and 3D reconstruction in patients with aortic coarctation

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EUROPEAN RADIOLOGY 1997年第9期7卷 1473-1477页

作者： Becker, C Soppa, C Fink, U Haubner, M MullerLisse, U Englmeier, KH Buhlmeyer, K Reiser, M DEUTSCH HERZZENTRUM MUNCHEN FREISTAATES BAYERN D-80335 MUNICH GERMANY GSF FORSCHUNGSZENTRUM UMWELT & GESUNDHEIT GMBH D-85764 OBERSCHLEISSHEIM GERMANY

The objective of this study was to assess the reliability of spiral CT angiography (CTA) and 3D reconstruction in patients with aortic coarctation (CoA). Eighteen patients with suspected or surgically proven coarctation were examined by spiral CT. In addition to the axial slices, 3D reconstructions, such as shaded surface display (SSD) and maximum intensity projection (MIP), were used to determine the diameters of the CoA and the pre-and poststenotic aorta and to visualise the collateral vessels. Diameters derived from cardiac catheterization were compared With those from CTA in 8 patients. The degree of aortic stenosis was correlated with blood pressure gradients (BPG) in 12 patients. The difference between the diameters of the CoA and the pre-and poststenotic aorta derived from MIP and angiography was not statistically significant (p = 0.69). With SSD the internal thoracic artery was detected in 16 and the posterior intercostal artery in 13 cases. The degree of aortic stenosis correlated poorly with the BPG (r = 0.51, r(2) = 0.26). CTA with 3D reconstruction rep.:resents a reliable noninvasive technique for the assessment of the degree of CoA and the visualisation of collateral vessels. It may serve as a follow-up investigation after intervention or surgical treatment.

关键词： X-ray CT aorta stenosis obstruction computer-assisted image processing thoracic aorta collateral circulation

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Digital radiographic measurement of approximal caries progression in fluoridated and non-fluoridated areas of Rio de Janeiro, Brazil

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COMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY 1997年第6期25卷 412-418页

作者： Lawrence, HP Benn, DK Sheiham, A UCL Dept Epidemiol & Publ Hlth London England London Hosp Coll Med Dept Dent Publ Hlth London E1 1BB England Univ Florida Coll Dent Dept Oral Surg & Diagnost Sci Gainesville FL USA

The effect of fluoridation on approximal caries progression was investigated using serial digitized bitewing images and conventional film images of 290 12-16-year-old schoolchildren who were lifetime residents of either Rio de Janeiro (a fluoridated area) or Mangaratiba and Angra dos Reis (non-fluoridated areas) in the state of Rio de Janeiro, Brazil. One examiner scored a maximum of 28 approximal surfaces of posterior teeth per subject using both methods. The intraexaminer reliability for rating lesion depth with digital images was comparable with that of the conventional bitewing films (namely, intraclass correlation of 0.99 and weighted Kappa scores of 0.82, respectively). Approximal surface D1S was 3.17+/-0.25 (s(x)) in fluoridated areas and 6.64+/-0.44 in non-fluoridated areas. After 1 year, the rate of caries progression in approximal surfaces was significantly lower in the fluoridated areas (0.54+/-0.14) as compared with the non-fluoridated areas (1.41+/-0.20) using Pitts' scoring system for conventional bitewing radiographs (P<0.001). Similarly, the digital radiographic method was able to detect subtle differences in approximal caries progression in the enamel and the dentin (overall mean: 0.34 mm/year in fluoridated areas vs 0.49 mm/year in nonfluoridated areas, P<0.05). The two radiographic methods were strongly correlated (r(s)=0.7). Assuming a constant rate over time, these results indicate that lesion progression from the outer half of the enamel into the outer half of the dentin takes approximately 3-4 years in schoolchildren from the fluoridated areas compared to 2 1/2 years in the non-fluoridated areas.

关键词： adolescence bitewing radiography caries progression computer-assisted image processing digital radiography fluoridation

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Skeletal pattern extraction of bone trabeculae using mathematical morphology

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Oral Radiology 1997年第1期13.0卷 35-43页

作者： Kumasaka, S. Matsuki, T. Kashima, I. Oral and Maxillofacial Radiology Kanagawa Dental College Yokosuka Kanagawa 238 82 Inaoka-cho Japan

Studies of morphology in extracting skeletal patterns of spiculae in mammograms served as a theoretical framework. Using studies of morphology in extraction of skeletal patterns of spiculae in mammograms as a theoretical framework, we applied a morphological filter (a combination of a skeleton operation and a single structuring clement) to the extraction of skeletal patterns of bone trabeculae on computed radiographic (CR) images. Then, the comparison of the original images with the extracted skeletal patterns and the relationship between the sequence number (n) of the operation and the extracted skeletal patterns was reviewed. The comparison showed that skeletal patterns of the original image were extracted as binary images when using a morphological filter, and that, when n was small (n=0 or 1), skeletal patterns of both fine and wider bone trabeculae were extracted. Furthermore, with an increase in n, skeletal patterns of fine bone were eliminated, and only wider skeletal patterns were extracted selectively. These findings suggest that development of a suitable morphological filter to extract the skeletal patterns of bone trabeculae may be an effective supplement for computer aided diagnosis of medical images (CADM) in the support of adequate diagnosis of bone diseases.

关键词： computer-assisted image processing Digital image processing image enhancement

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Computed tomography intravenous cholangiography

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Australasian Radiology 1997年第3期41卷 253-261页

作者： Nascimento, Sherry Murray, Wynne Wilson, Peter Pittwater Radiology Dee Why NSW Australia Pittwater Radiology Dee Why NSW 2099 812 Pittwater Road Australia

Indications for direct visualization of the bile ducts include bile duct dilatation demonstrated by ultrasound or CT scanning, where the cause of the bile duct dilatation is uncertain or where the anatomy of bile duct obstruction needs further clarification. Another indication is right upper quadrant pain, particularly in a post-cholecystectomy patient, where choledocholithiasis is suspected. A possible new indication is pre-operative evaluation prior to laparoscopic cholecystectomy. The bile ducts are usually studied by endoscopic retrograde cholangiopancreatography (ERCP), or, less commonly, trans-hepatic cholangiography. The old technique of intravenous cholangiography has fallen into disrepute because of inconsistent bile-duct opacification. The advent of spiral CT scanning has renewed interest in intravenous cholangiography. The CT technique is very sensitive to the contrast agent in the bile ducts, and angiographic and three-dimensional reconstructions of the biliary tree can readily be obtained using the CT intravenous cholangiogram technique (CT IVC). Seven patients have been studied using this CT IVC technique, between February 1995 and June 1996, and are the subject of the present report. Eight further studies have since been performed. The results suggest that CT IVC could replace ERCP as the primary means of direct cholangiography, where pancreatic duct visualization is not required.

关键词： Bile ducts Cholangiography computer-assisted image processing X-ray computed tomography

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