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An original computer program designed to help in histological diagnosis of thyroid tumours is presented. The literature is given on the use of computer technologies in current morphology.
OBJECTIVES: The purpose of this study was to assess morphology and composition of culprit and stable coronary lesions by multidetector computed tomography (MDCT). BACKGROUND: Noninvasive identification of culprit lesions has the potential to improve noninvasive risk stratification in patients with acute chest pain. METHODS: Thirty-seven patients with acute coronary syndrome (ACS) or stable angina underwent coronary 16-slice MDCT and invasive selective angiography. In all significant coronary lesions two observers measured the degree of stenosis, plaque area at stenosis, and remodeling index and assessed plaque composition. Differences between culprit lesions in patients with ACS and stable lesions in patients with ACS or stable angina were determined. RESULTS: We analyzed 40 lesions with excellent image quality in 14 patients with ACS and 9 patients with stable angina. Culprit lesions in patients with ACS (n = 14) had significantly greater plaque area and a higher remodeling index than both stable lesions in patients with ACS (n = 13) and in patients with stable angina (n = 13) (17.5 +/- 5.9 mm2 vs. 9.1 +/- 4.8 mm2 vs. 13.5 +/- 10.7 mm2, p = 0.02; and 1.4 +/- 0.3 vs. 1.0 +/- 0.4 vs. 1.2 +/- 0.3, p = 0.04, respectively). The prevalence of non-calcified plaque was 100%, 62%, and 77%, respectively, and the prevalence of calcified plaque was 71%, 92%, and 85%, respectively, in culprit lesions in patients with ACS and in stable lesions in patients with ACS or stable angina. CONCLUSIONS: We introduce the concept of noninvasive detection and characterization of coronary atherosclerotic lesions in patients with ACS by MDCT. We identified differences in lesion morphology and plaque composition between culprit lesions in ACS and stable lesions in ACS or stable angina, consistent with previous intravascular ultrasound studies.
The reduction in size of the ventricular areas in the computer tomogram as a morphological substrate of a generalised cerebral edema in 43 patients correlated better with the vigilance than with the EEG findings. This fact as well as the representation possibility of additional intracranial haemorrhages favour the computer tomography in the posttraumatic acute phase as compared to the electroencephalography, which should be employed in the subacute phase.
The morphology of pancreatic carcinoma as determined by sonography and computer-assisted tomography is described. Differential diagnosis and diagnostic pitfalls are discussed.
A computer-assisted measurement of synrinxes was performed on MR images in a series of 26 patients with syringomyelia-Chiari complex. Syrinx data such as length, surface area, contour, and greater diameter were statistically correlated to each other and with the main clinical symptomatology of the patients. In general, a direct relationship between the various measurements of the syrinxes exists. Nevertheless, although a slight relationship could be established between the presence of muscular atrophy and a greater length and contour of the syrinxes, the present study suggests that the evaluation of syrinx dimensions cannot be brought into relation with the nature or distribution of clinical symptomatology. Because a reduction in the syrinx is generally the aim of surgery, this conclusion should be born in mind when a surgical treatment is offered to syringomyelic patients.
Multi-detector computed tomography (MDCT) permits detection of coronary plaque. However, noise and blurring impair accuracy and precision of plaque measurements. The aim of the study was to evaluate MDCT post-processing based on non-linear image deblurring and edge-preserving noise suppression for measurements of plaque size. Contrast-enhanced MDCT coronary angiography was performed in four subjects (mean age 55 +/- 5 years, mean heart rate 54 +/- 5 bpm) using a 16-slice scanner (Siemens Sensation 16, collimation 16 x 0.75 mm, gantry rotation 420 ms, tube voltage 120 kV, tube current 550 mAs, 80 mL of contrast). Intravascular ultrasound (IVUS; 40 MHz probe) was performed in one vessel in each patient and served as a reference standard. MDCT vessel cross-sectional images (1 mm thickness) were created perpendicular to centerline and aligned with corresponding IVUS images. MDCT images were processed using a deblurring and edge-preserving noise suppression algorithm. Then, three independent blinded observers segmented lumen and outer vessel boundaries in each modality to obtain vessel cross-sectional area and wall area in the unprocessed MDCT cross-sections, post-processed MDCT cross-sections and corresponding IVUS. The wall area measurement difference for unprocessed and post-processed MDCT images relative to IVUS was 0.4 +/- 3.8 mm2 and -0.2 +/- 2.2 mm2 (p < 0.05), respectively. Similarly, Bland-Altman analysis of vessel cross-sectional area from unprocessed and post-processed MDCT images relative to IVUS showed a measurement difference of 1.0 +/- 4.4 and 0.6 +/- 4.8 mm2, respectively. In conclusion, MDCT permitted accurate in vivo measurement of wall area and vessel cross-sectional area as compared to IVUS. Post-processing to reduce blurring and noise reduced variability of wall area measurements and reduced measurement bias for both wall area and vessel cross-sectional area.
BACKGROUND AND OBJECTIVE: Pulmonary embolism often extends to pleural surfaces, resulting in pleural-based parenchymal lesions. This study was carried out in order to evaluate the clinical value of transthoracic sonography (TS) for the diagnosis of pulmonary embolism. PATIENTS AND METHODS: A prospective study was performed in 45 patients (27 men, 18 women; mean age: 63.4 years; range: 24-88 years) with suspected pulmonary embolism. Transthoracic sonography was performed in all patients. In addition, helical computed tomography (CT) was carried out in 40 patients. Other diagnostic procedures included the estimation of D-dimeres, echocardiography, venous duplex sonography of the legs and ventilation/perfusion scanning. The diagnosis of pulmonary embolism was accepted when an embolus was detected on CT or as a conclusive result of the other investigations. RESULTS: Pulmonary embolism was established in 33 patients. Peripheral parenchymal lesions suspicious of pulmonary embolism were detected by transthoracic sonography in 26 patients (79%). In seven patients with central pulmonary embolism diagnosed by CT, no peripheral lesions could be detected by sonography. One patient with sonographic signs of pulmonary embolism had a diffuse bronchogenic adenocarcinoma which was diagnosed on autopsy. The sensitivity of transthoracic sonography (computed tomography) for pulmonary embolism was 79% (76%) and the specificity 92% (100%). The positive and negative predictive values of transthoracic sonography for the detection of pulmonary embolism were 96% and 61% (100% and 61%), respectively. The accuracy was 82% (82%). CONCLUSIONS: A substantial number of pulmonary emboli involve the peripheral lung areas. Transthoracic sonography is a non-invasive technique for diagnosing such parenchymal alterations and may serve as an alternative method in the diagnosis of pulmonary embolism.
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83 patients with a transient ischemic attack have been investigated by computerized tomography. 71 patients had symptoms in the region of the middle cerebral artery, 12 in the basilar region. In 14 patients a hypodense lesion in the CT was found. Two of those patients showed multiple lesions. Two of those patients showed multiple lesions. The lesion affected always the region of the middle cerebral artery. Atrophy mostly of minimal degree was diagnosed in 31 patients.
The alleged relationship between the cross sectional shape of the hair shaft and the form of the hair, eg, curly or straight hair, has been challenged. By serial sections of human hair follicles from ten patients representing the three biological races, the relation between the follicle form and the hair form was studied. Using three-dimensional computer-aided reconstruction it was demonstrated that the follicle form determines the hair form, eg, the Negroid follicle has a helical form, whereas that of the Oriental follicle is completely straight. The caucasoid follicle represent variation between these extremes. However, even a straight caucasoid follicle may produce a hair shaft that has an oval cross section.
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OBJECTIVE: The aim of this study was to analyze the potential usefulness of MR signal intensity in differentiating malignant from benign pleural disease. SUBJECTS AND METHODS: Forty-five patients with pleural lesions identified on CT scans were subsequently examined by MR imaging at 0.5 T. T1-weighted, proton density-weighted, T2-weighted, and enhanced T1-weighted spin-echo images were obtained. For 34 patients, a diagnosis of malignant (n = 18) or benign (n = 16) disease was established. The morphologic features of the pleural lesions and MR signal intensity on T1-weighted, proton density-weighted, T2-weighted, and enhanced T1-weighted images were evaluated, and the ratio of lesion to muscle signal intensity was computed. RESULTS: Assessment of morphologic features by MR imaging and CT was not significantly different. High signal intensity on proton density-weighted and T2-weighted images was observed in all malignant lesions and in two benign lesions (sensitivity, 100%; specificity, 87%; negative predictive value, 100%). The ratio of lesion to muscle signal intensity on T1-weighted, proton density-weighted, T2-weighted, and enhanced T1-weighted images discriminated between malignant and benign lesions (p < .0001). For the subgroup of lesions misinterpreted by CT (n = 6), the evaluation of MR signal intensity on long-TR images made it possible to differentiate malignant from benign conditions. CONCLUSION: MR signal intensity is a valuable additional feature for differentiating malignant from benign pleural disease. Signal hypointensity with long-TR sequences is a reliable predictive sign of benign pleural disease.
OBJECTIVE: Echolucency of carotid atherosclerotic plaques, as evaluated by computerized B-mode ultrasonographic images, has been associated with an increased incidence of brain infarcts on cerebral computed tomographic scans. We tested the hypotheses that characterization of carotid plaques on spiral computed tomographic images correlates with that on computerized B-mode ultrasonographic images and that spiral computed tomographic imaging predicts the histomorphometric plaque content. METHODS: The study included 38 patients with neurologic symptoms and at least 50% stenosis of the ipsilateral carotid artery. High-resolution B-mode ultrasonographic images and spiral computed tomographic images of carotid plaques were computer processed to yield a quantitative measure, the gray scale level of the plaque. RESULTS: The mean Hounsfield value for spiral computed tomographic images correlated with the gray scale median for B-mode ultrasonographic images (univariate linear regression analysis: r = 0.45; P = .01) and the histologic content of calcification in the plaque (r = 0.34; P = .04) but not with lipid, hemorrhage, or fibrous tissue in the plaque. CONCLUSIONS: Spiral computed tomographic imaging seems to correlate with B-mode ultrasonographic imaging for showing plaque characteristics. Spiral computed tomographic attenuation was also correlated with the amount of calcification noted on histologic examination but not with lipid and hemorrhage, the components thought to characterize vulnerable, rupture-prone plaques.
BACKGROUND: Directional coronary atherectomy has recently become available to treat coronary stenoses. This study was performed to determine the relation of patient characteristics and stenosis morphology to procedural outcome with directional coronary atherectomy to gain insight into which patients might be best treated with this device. METHODS AND RESULTS: Four hundred stenoses from 378 patients consecutively treated at six major referral institutions were analyzed. Angiographic data were assessed at a central angiographic laboratory using standardized morphological criteria and computer-assisted quantitative dimensional analyses. Procedural success was achieved in 87.8% of stenoses, and major ischemic complications (death, myocardial infarction, and emergency bypass surgery) occurred in 6.3% of patients. Lesion success and complications were closely correlated with recognized modified American College of Cardiology/American Heart Association Task Force lesion morphological criteria. Observed for type A stenoses were 93% success and 3% complication rates; for type B1 stenoses, 88% success and 6% complication rates; and for type B2 stenoses, 75% success and 13% complication rates, respectively. There were too few type C stenoses treated to analyze. Furthermore, multivariate testing demonstrated stenosis angulation (multivariate p less than 0.001), proximal tortuosity (p less than 0.001), decreased preatherectomy minimum lumen dimension (p = 0.032), and calcification (p = 0.041) to correlate independently with adverse outcome and complex, probably thrombus-associated stenoses to have a favorable outcome (p = 0.055). Operator experience (p = 0.020) and a history of restenosis (p = 0.022) also favorably influenced outcome. CONCLUSIONS: The procedural outcome of directional coronary atherectomy is highly associated with coronary stenosis morphology. Furthermore, after appropriate stratification for morphology and clinical presentation, overall atherectomy procedural outcome may be similar to that achieved with coronary angioplasty. However, specific subsets of patients may have relatively better outcome with either atherectomy or balloon angioplasty.
OBJECTIVES: To characterize how the morphological features of the cancellous bone of the maxilla and mandible differ in patients with sickle cell anemia compared with normal subjects. METHODS: Periapical radiographs of 18 young African American patients with sickle cell anemia and 18 control African Americans were digitized at 600 d.p.i. A customized computer program measured 24 morphological features of the trabecular and marrow architecture in the anterior maxilla and mandible. The mean values for each of the features were determined for the sickle cell and control groups and compared by anatomical site. RESULTS: Patients with sickle cell anemia have a significant increase in area of the marrow (53% compared with 47% in controls) and a less complex trabecular structure as evidenced by fewer skeletal branch points per square cm (451 compared with 584 in controls in the anterior maxilla and, 553 compared with 678 in controls in the anterior mandible). All values are significantly different (P < 0.001). CONCLUSIONS: The data support the hypothesis that an automated image-interpretation program can distinguish patients with sickle cell anemia from normal individuals.
BACKGROUND: Global hypomethylation of DNA is frequently observed in human tumours. This alteration is detected in early adenomas in colorectal tumorigenesis. Information is currently acquired after extraction of DNA from tissues, digestion with nucleases, and analysis by reverse phase chromatography, or treatment with restriction enzymes followed by gel electrophoresis analysis and Southern hybridisation with radiolabelled probes. AIMS: The purpose of our work was to evaluate the global methylation status of DNA in malignant lesions without loosing the histopathological features of the samples. PATIENTS: The investigation was performed on paired normal-tumour tissues from 13 patients undergoing surgical resection of colorectal adenocarcinomas. METHODS: Antibodies raised against 5-methylcytidine can be used to label methyl rich regions in interphase nuclei. This technique was adapted to the study of paraffin embedded tissues and an immunohistochemical method was developed to assess the global methylation status of individual nuclei while preserving cell morphology and tissue architecture. Computer assisted quantification of the staining intensity was performed on malignant and normal zones of human colon tissues to test the correlation between the immunolabelling signal and the respective histological patterns observed. RESULTS: Qualitative and quantitative differences were observed and measured between the normal and malignant part of each sample. Morphologically altered nuclei displayed densely labelled spots within faintly labelled areas whereas normal nuclei were darker and uniformly stained. Image analysis allowed calculation of the average integrated optical density of the nuclei in both types of tissues, demonstrating a constant and significantly lower intensity for the former type of cells.
As a model for the effect of hormones and growth factors on three-dimensional growth of mammalian cells, we have analyzed the effect of insulin on the three-dimensional growth and morphology of Chinese hamster ovary (CHO) colonies grown on the surface of agar. Sequential photographs in dark-field illumination of growing colonies have been analyzed with computer-assisted techniques. In this analysis the entire shape of each colony in a sizeable population (up to 10(5) colonies per experiment) can be measured and distributions of parameters derived from these measurements can be studied. In fetal calf serum (FCS), insulin has a dose-related stimulatory effect on cell growth that is most pronounced when growth has slowed down. In 10% FCS, insulin has a similar but diminished effect. When CHO cells are grown conventionally on plastic substrata or in suspension, insulin has little effect on cell growth at 4% serum concentration. Computer analysis of changes in the distribution of colony morphology proved to be a sensitive, dose-dependent, and reproducible assay of a hormonal effect. As little as 5 ng of insulin per ml added to 10% FCS causes a shift in the distribution of colony morphologies. In 4% FCS, 50 ng of insulin per ml is required to produce a detectable change in the colony morphology distribution. Computer analysis of cells grown three-dimensionally on agar provides a powerful approach to studying the effects of hormones and provides observations not available when cells are grown on plastic substrata.
Two cases are reported of surgically confirmed acute spinal epidural haematoma demonstrated by computed tomography at the time of presentation. Five distinct appearances were encountered. The variable morphology and the role of computed tomography in diagnosing this condition are discussed.