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PubMed1990

[Histologic grade, DNA content and image analysis in soft tissue tumors].

Flow cytometry and image analysis technique were used to quantitate the nuclei of various soft tissue tumors. A single representing section from soft tissue sarcoma was used for histologic grading. Histologic and cytometric comparative analyses showed that all 21 benign tumors were diploid. Among 62 cases of soft tissue sarcoma, 45 (73%) were aneuploid. There was a significant difference in the nuclear area between benign and malignant tumors (P less than 0.01), diploid and aneuploid tumors (P less than 0.05). The two new techniques are valuable in cellular quantitative measurement for soft tissue tumors.

Adolescent↗
PubMedDate not supplied

A new method for lumbar herniated inter-vertebral disc diagnosis based on image analysis of transverse sections.

This paper describes an image analysis method that uses automatic algorithms for the evaluation of herniation classification and geometry in the diagnosis of lumbar herniated inter-vertebral disc (HIVD). The method uses boundary approximation that uses a B-spline curve to approximate circle-like disc boundary and excludes the herniation from other normal parts of the disc boundary and, feature recognition that classifies the herniation, and herniation shape reconstruction that infers the 3D geometry from one or more transverse sections. This method can be used as a qualitative and quantitative tool for the diagnosis of lumbar HIVD using transverse sections.

Adult↗
PubMedDate not supplied

Image analysis of particle dispersions in microscopy images of cryo-sectioned sausages.

Two feature extraction methods, the three-dimensional (3-D) local box-counting method and the area distribution method, are presented to describe the fat dispersion pattern on digital microscopy images of cryo-sectioned sausages. Both methods calculate whole arrays of variables for each microscopy image. The 3-D box-counting method calculates scale dependent (local) dimensions. This is in contrast to common fractal methods, which are univariate. Principal component analysis (PCA) was used to show that different sausages yield different fat dispersion patterns. Partial least square regression (PLS) shows that there is a correlation between the variables gained with both methods and the fat content.

Animals↗
PubMed1984

[Estimation of ventricular activation by scintigraphic phase image analysis].

We examined the capabilities of scintigraphic phase imaging in detecting the site of the onset of ventricular activation and the pattern of ventricular activation sequence. ECG-gated equilibrium cardiac blood pool scintigraphy was obtained in the left anterior oblique (LAO) and right anterior oblique (RAO) projections. The standard 12-lead electrocardiograms (ECG) were recorded in 29 cases with various conditions. These included seven normal subjects as controls, eight patients (pts) with complete right bundle branch block (CRBBB), one with CRBBB and left axis deviation (LAD), two with complete left bundle branch block (CLBBB), one with the Wolff-Parkinson-White (WPW) syndrome (B-type), six with right ventricular apical endocardial pacemakers, one with a right ventricular anterior wall myocardial pacemaker, and three with left ventricular apical myocardial pacemakers. Phase image analysis was performed using the first harmonic of the Fourier transform to fit a cosine curve to the time-activity curve of each pixel in the cardiac blood pool study. The results were as follows: In pts with WPW syndrome (B-type) and artificial pacemakers, the site of the earliest phase angle corresponded to the site of the onset of ventricular activation as predicted by ECG and chest radiographs, respectively. However, in normal subjects and in pts with CRBBB, the site of the earliest phase angle was observed at the basal (upper) interventricular septum, which was different from the site of the onset of ventricular activation previously reported by Sodi-Pallares et al and Durrer et al. This discrepancy may have been caused by the paradoxical motion of the basal (upper) interventricular septum in those cases. A similar discrepancy was also observed in pts with CLBBB. Although the site of onset of ventricular activation was predicted to be near the insertion of the anterior papillary muscle of the right ventricle by ECG and electrophysiology, the pixels showing early phase angle were distributed widely along the interventricular septum in those pts with CLBBB. This error in the phase image may have been caused by the extensive paradoxical motion of the interventricular septum. Thus, caution should be exercised in estimating the site of the onset of ventricular activation by phase images. The main direction of phase changes corresponded well to the ventricular activation sequence estimated using ECG in all subjects.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed2006

Functional imaging analysis contest (FIAC) analysis according to AFNI and SUMA.

The Functional Imaging Analysis Contest (FIAC) datasets were analyzed with the AFNI software package. Two types of linear regression analyses were carried out: "fixed shape" hemodynamic response, where a preselected incomplete gamma function is used to model each brief activation episode, and "variable shape" analysis, where the temporal shape of the response model in each stimulus block class is allowed to vary separately in each voxel. These time series regressions were carried out both in the volume and on the original data projected to individual standardized cortical surface models. Intersubject analyses were carried out voxel-wise on the regression amplitudes obtained from these time series results, using a multi-way within-subject analysis of variance (ANOVA). Group analysis of the block design demonstrated a significant repetition suppression of the BOLD signal within blocks in the superior and middle temporal gyrus. This effect may represent differences in the response to the first stimulus following a period of silence compared to the remaining sentences in the block. Analyzing the event-related data, Brodmann area 31 showed significant sentence effect and consecutive-sentence repetition effect. However, no significant speaker effect was found; these results may be consistent with the instructions to the subjects that they would be tested on the sentence content. Sentence by speaker interaction effects were found in bilateral middle temporal gyrus, left inferior frontal, and left inferior temporal gyrus.

Brain Mapping↗
PubMed2005

Teaching medical image analysis with the Insight Toolkit.

We present several case studies which examine the role that the Insight Toolkit (ITK) played in three medical image analysis courses and several conference tutorials. These courses represent the first use of ITK in a teaching environment, and we believe that a discussion of the teaching approach in each case and the benefits and challenges of ITK will be useful to future medical image analysis course development. ITK was found to provide significant value in a classroom setting since it provides both working "canned" algorithms, including some recently developed methods that are unavailable elsewhere, as well as a framework for developing new techniques and applications. Several areas of difficulty, particularly in regards to code complexity and advanced object-oriented design techniques, have been identified which may make the learning curve of ITK somewhat more complex than a language such as Matlab.

Algorithms↗
PubMed1989

Bone ingrowth into porous coated canine total hip replacements. Quantification by backscattered scanning electron microscopy and image analysis.

Bone ingrowth into titanium fiber mesh porous-surfaced canine total hip replacement prostheses was evaluated and quantified using a computer assisted image analysis system attached to a scanning electron microscope equipped with a back scattered electron detector. Excellent contrast between the bone, the porous metal and the soft tissues resulted in the backscatter mode, allowing easy differentiation of these components in real time by the image analysis based on gray scales. By three weeks the mean (+/- standard deviation) amount of bone ingrowth expressed as a percentage of porous layer measured 7.2% (+/- 1.5%) for the acetabular components, and 3.9% (+/- 1.7%) for the femoral components. At six weeks the amount of bone ingrowth increased to 10.5% (+/- 1.3%) for the acetabular components and 8.5% (+/- 1.4%) for the femoral components. Cementless prosthetic fixation using porous surfaced prostheses holds great promise in joint replacement surgery, and the ability to quantitate the amount of bone ingrowth will permit the evaluation of the efficacy of various techniques to improve bone ingrowth.

Animals↗
PubMed1989

A computerized image analysis method for measuring elastic tissue.

A computerized image analysis technique for quantifying area fractions of elastic tissue in light microscopic sections is presented that considers the nonuniform distribution of the elastic tissue. The method uses Verhoeff-van Gieson stained sections. The analysis is stratified vertically in three uniform layers starting at the dermo-epidermal junction and horizontally by two schemes. A standard method consists of five equally spaced measurements. The densest method uses the three areas that contain the most elastic tissue. The area fractions are determined by counting the positive and total pixels (thresholding). A validity test utilizing independent physical measurements demonstrated differences of no more than 1.7%. Reliability tests for reading the same section on different days and adjacent sections showed no significant differences (p less than 0.05) between the readings. Reliability tests of sections using different stain lots and adjacent biopsy sites also did not have significant differences. This method may be particularly useful for studies in which the distribution of the material to be measured may be very uneven, such as in solar elastosis.

Biopsy↗
PubMed2002

Automated identification of diploid reference cells in cervical smears using image analysis.

BACKGROUND: Acquisition of DNA ploidy histograms by image analysis may yield important information regarding the behavior of premalignant cervical lesions. Accurate selection of nuclei for DNA measurement is an important prerequisite for obtaining reliable data. Traditionally, manual selection of nuclei of diagnostic and reference cells is performed by an experienced cytotechnologist. In the present study, a method for the fully automated identification of nuclei of diploid epithelial reference cells in Feulgen- restained Papanicolaou (PAP) smears is described. METHODS: The automated procedure consists of a decision tree implemented on the measurement device, containing nodes with feature threshold values and multivariate discriminant functions. Nodes were constructed to recognize debris and inflammatory cells, as well as diploid and nondiploid epithelial cells of the uterine cervix. Evaluation of the classifier was performed by comparing resulting diploid integrated optical densities with those from manually selected reference cells. RESULTS AND CONCLUSION: On average, automatically acquired values deviated 2.4% from manually acquired values, indicating that the method described in this paper may be useful in cytometric practice.

Algorithms↗
PubMed1991

Morphometric studies in intraductal breast carcinoma using computerized image analysis.

A morphometric study was performed using computerized image analysis on the histologic specimens of 26 patients with intraductal carcinoma of the breast and 26 normal control patients. A significant incidence of necrosis (56%) was observed in the breast ducts containing intraductal carcinoma. This was characterized by one or more areas of necrosis surrounded by a rim of viable tumor cells. The mean diameter of the ducts containing intraductal carcinoma was 349 microns compared with a mean diameter of 90 microns for the normal ducts. The mean diameter of the ducts containing necrosis was 470 microns compared with a mean diameter of 192 microns for the ducts containing a solid pattern of intraductal carcinoma. Central necrosis occurred in 94% of the ducts more than 180 microns in radius, whereas only 34% of the ducts less than 180 microns in size contained necrosis. The width of the viable neoplastic tissue was less than 180 microns in 91% of the ducts. These results are analogous to the findings of Thomlinson and Gray in human lung tumor cords and provide indirect evidence for the existence of a hypoxic compartment in intraductal carcinoma of the breast. This could be an explanation for the higher local failure rate after conservative surgery and irradiation for infiltrating cancers containing an extensive intraductal component.

Adult↗
PubMed1995

A preliminary study of skin electrical injury with computerized image analysis.

This paper reports the application of computerized image analysis to a quantitative study of skin electrical injury in order to provide an objective and quantitative standard for identifying the electrical mark. The differences between antemortem and postmortem electrical injuries were also studied. In normal and electrically-injured human skin, the long/short axes ratio of nuclei were measured. The mean of epithelial basal cells was 1.4344 and 5.9325, respectively, the mean of hair follicle cells was 1.6193 and 4.5988, respectively, and the mean of capillary endothelial cells was 4.0229 and 4.3593, respectively. In rat specimens, the long/short axes ratio of nuclei of normal skin, at 15 and 5 min ante-mortem and at 5 min postmortem injury, the mean epithelial basal cells was 1.4124, 4.5417, 5.2282 and 5.0447, respectively. The mean of hair follicle cells was 1.4140, 4.4863, 4.1146 and 4.4522, respectively, while the mean of capillary endothelial cells was 2.8398, 3.7514, 3.6159 and 3.6977, respectively. The results indicate that the differences between electrical injuries and normal skin with respect to the ratios of long/short axes of the epithelial basal cell nuclei and hair follicle cell nuclei are of remarkable significance. On the other hand, no significant difference could be found between antemortem and postmortem injuries, nor between electrical injury and normal skin, concerning the long/short axes ratios of capillary endothelial cell nuclei. This result provides a preliminary objective standard for the changes of electrical skin injury.

Animals↗
PubMed1993

Comparative analysis of DNA ploidy and proliferative index in fine needle aspirates of non-Hodgkin's lymphomas by image analysis and flow cytometry.

To determine the application of image analysis (IA) to fine needle aspiration (FNA) of non-Hodgkin's lymphomas, 78 cases, categorized according to the Working Formulation, were analyzed and compared with those analyzed by flow cytometry (FCM). Aspirated material was immediately fixed in either IA fixative (31 cases) or acetone, stored at -70 degrees C (47 cases) for periods up to 48 months and postfixed in IA fixative. IA assessed DNA index (DI), ploidy balance, degree of hyperdiploidy and proliferation index (PI). DNA index, % S + G2M and RNA index were obtained by acridine orange FCM. There were no significant differences in measured variables between fresh and stored cases. Statistically significant differences between low, intermediate and high grade lymphomas were present in all evaluated variables except DNA ploidy (DI) (P = .074) measured by IA. DI, however, showed a very high correlation with the DI obtained by FCM (r = .94). PIs, although generally lower, also had a high correlation with S + G2M (r = .85). We conclude that results obtained by IA were comparable to results by FCM and that frozen material can be used to retrospectively evaluate ploidy and proliferation. IA is especially suitable for the evaluation of low-volume specimens obtained by FNA.

Biopsy, Needle↗
PubMed1983

Determination of myosin light chain phosphorylation using astronomical image analysis programs on autoradiographs of electrophoretic gels.

Computer image analysis programs developed by astronomers for celestial photometry were used for the analysis of autoradiographs of electrophoretic slab gels. Oxytocin-stimulated myosin light chain phosphorylation in mammary myoepithelial cells was studied by incubating cells with [32P]orthophosphate followed by oxytocin addition, polyacrylamide gel electrophoresis of cellular protein, and autoradiography of electrophoretic slab gels. After scanning and digitization of autoradiographs, [32P]phosphate incorporation into the myosin light chain was measured by the determination of radiation flux recorded on the X-ray film. Within seconds after oxytocin addition, the myosin light chain was fully phosphorylated. The large library of astronomical computer programs has applications for the quantitative analysis of both one- and two-dimensional electrophoretic gels.

Autoradiography↗
PubMed1998

Determination of bacterial cell dry mass by transmission electron microscopy and densitometric image analysis.

We applied transmission electron microscopy and densitometric image analysis to measure the cell volume (V) and dry weight (DW) of single bacterial cells. The system was applied to measure the DW of Escherichia coli DSM 613 at different growth phases and of natural bacterial assemblages of two lakes, Piburger See and Gossenköllesee. We found a functional allometric relationship between DW (in femtograms) and V (in cubic micrometers) of bacteria (DW = 435.V0.86); i.e., smaller bacteria had a higher ratio of DW to V than larger cells. The measured DW of E. coli cells ranged from 83 to 1,172 fg, and V ranged from 0.1 to 3.5 micron 3 (n = 678). Bacterial cells from Piburger See and Gossenköllesee (n = 465) had DWs from 3 fg (V = 0.003 micron 3) to 1,177 fg (V = 3.5 microns3). Between 40 and 50% of the cells had a DW of less than 20 fg. By assuming that carbon comprises 50% of the DW, the ratio of carbon content to V of individual cells varied from 466 fg of C micron-3 for Vs of 0.001 to 0.01 micron3 to 397 fg of C micron3 (0.01 to 0.1 micron3) and 288 fg of C micron3 (0.1 to 1 micron 3). Exponentially growing and stationary cells of E. coli DSM 613 showed conversion factors of 254 fg of C micron-3 (0.1 to 1 micron3) and 211 fg of C micron-3 (1 to 4 micron3), respectively. Our data suggest that bacterial biomass in aquatic environments is higher and more variable than previously assumed from volume-based measurements.

Bacteria↗
PubMed2001

Automated monitoring of activated sludge in a pilot plant using image analysis.

An automated procedure for the characterisation by image analysis of the morphology of activated sludge has been used to monitor the biomass in a pilot wastewater treatment plant, in complement to the usual settleability (sludge volume index, settling velocity) and size distribution (by laser granulometry) measurements.

Automation↗
PubMed1992

Comparison of image analysis with flow cytometry for DNA content analysis in pigmented lesions of the skin.

The DNA ploidy of 85 melanocytic skin lesions was determined by flow cytometry (FCM) and interactive image analysis (IA) using nuclear extracts of paraffin-embedded tissue. Of the 85 lesions analyzed, 43 were malignant melanomas in different stages of evolution, 15 were dysplastic nevi, 11 were Spitz nevi, and 16 were other types of nevi. Some of the last had features of congenital nevi. Within the melanoma category, there was 42% aneuploidy by FCM versus 56% by IA. Of those melanomas aneuploid by FCM, all but one were aneuploid by IA. All dysplastic nevi, 10/11 Spitz nevi and 15/16 other nevi were diploid by both methods. One of the 16 nevi from the "other types" category was tetraploid by IA but diploid by FCM. A single Spitz nevus was tetraploid by FCM but diploid by image analysis. While our results suggest that interactive IA is potentially a more sensitive method than FCM for detecting aneuploidy in cutaneous pigmented lesions, it remains to be shown whether this will translate into better prognostic assessment of the biologic behavior of melanocytic neoplasms than provided by flow cytometric ploidy analysis.

Aneuploidy↗
PubMed2000

Automated image analysis for monitoring oxidative burst in macrophages.

OBJECTIVE: To evaluate oxidative bursts induced by phorbol myristate acetate in phagocytes at the single-cell level by automated image analysis. STUDY DESIGN: The generation of reactive oxygen species was quantitatively expressed by means of histograms displaying the percentage of cells corresponding to each of the total optical densities measured. RESULTS: Macrophage subpopulations were quantitatively defined. This method allows detailed analysis of the amount of formazan per cell and the sites of deposition of blue precipitate in each cell. CONCLUSION: Image analysis is a reliable quantitative, single-cell assay for studying various cellular characteristics associated with macrophage functions.

Animals↗
PubMed1990

DNA quantification in colorectal carcinoma using flow and image analysis cytometry.

Numerous studies using flow cytometry (FCM) have shown that DNA quantification and ploidy classification can provide information of prognostic significance for patients with colorectal carcinoma; recent advances in image analysis cytometry (image cytometry, ICM) provide a new, alternative technique for DNA quantification. This study investigated whether (1) patients with colorectal carcinomas that exhibit a diploid pattern of DNA distribution have improved five-year survival statistics as compared to their non-diploid counterparts and (2) ICM provides quantitative data comparable to that obtained by FCM. DNA quantification and ploidy classification of 27 cases of primary colorectal carcinoma was performed on archival paraffin-embedded tissue by both FCM and ICM; 70% (19) of the tumors were classified as nondiploid by ICM while 56% (15) were similarly classified by FCM. Diploid tumors were associated with Dukes' stage A while nondiploid tumors were associated with Dukes' stage D. The overall five-year survival rate was 75% for patients with ICM diploid tumors and 67% for patients with FCM diploid tumors. The five-year survival was only 53% for patients with nondiploid tumors identified by both techniques. This study confirmed that DNA quantification is an important prognostic indicator for patients with colorectal carcinoma. It also showed that ICM provides data comparable to that of FCM and may be more sensitive.

Colorectal Neoplasms↗