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PubMed1990

[Centroblast morphology: a morphometric evaluation by means of computer-aided image analysis].

In cytologic preparations, cell images from 30 cases of high grade malignant Non-Hodgkin's lymphoma (NHL) and 10 cases of tonsillitis have been analysed using a colour TV microscope system, high resolution scanning and image processing. Multivariate analysis of 30 cell features allowed satisfying recognition and discrimination of centrocytes, centrocyte-like centroblasts, ordinary centroblasts and multilobated centroblasts. In addition, according to their image analytical data, the ordinary centroblasts from NHL formed 5, and those from tonsillitis 4 well defined, homogeneous clusters. Even at simultaneous analysis, there was an essential overlap only between centroblast subtype 3 from NHL and subtype 9 from tonsillitis, but reliable discrimination of all the rest.

Computers↗
PubMedDate not supplied

[Computed tomography in the evaluation of tumor regression after neoadjuvant therapy: X-ray surgery and X-ray morphological comparisons].

An analysis was made of chest computed tomograms of 38 small-cell lung cancer patients subjected to radical surgical treatment after neoadjuvant therapy. CT data were compared with the findings of macro- and microscopic examination of surgical specimens. In 24 (63.2%) patients, computed tomograms made before surgery showed complete tumor response confirmed by gross examination in 22 (96.1%) of them. However, microscopic examination found cancer cells in 8 (33.3%) patients. In 2 (8.3%) patients, small residual tumors could be detected by sight, which was confirmed by pathological examination. In 14 (36.8%) patients with partial response, radiological and gross examination findings fully coincided. Nevertheless, in 2 (14.3%) cases the "residual tumor" appeared to be a segment of fibrocicatrical tissue under pathological examination. On the basis of the CT findings the values of diagnostic sensitivity, accuracy and specificity in tumor response evaluation were calculated which made up 87.5%, 68.4% and 54.5% respectively. With sufficiently high sensitivity, CT specificity is low. CT makes it possible to objectively define the response of small-cell lung cancer to neoadjuvant therapy. However, the conclusion about complete response to the treatment can be made only on the basis of a comprehensive evaluation of the results of all available investigation methods and pathological examination.

Carcinoma, Small Cell↗
PubMedDate not supplied

[Prognostic evaluation in multiple myeloma. Relationship between immunological types, single prognostic factors, clinical staging systems, morphological classification systems and survival].

The prognostic value of the multiple myeloma (MM) immunological type, of 20 different single prognostic variables, of 11 clinical staging systems, and of 6 morphological classification systems was evaluated in 121 patients (71 males and 50 females, 75 MM IgG, 26 MM IgA, and 20 MM micromolecular), who were followed from diagnosis to demise. The values of the prognostic variables related to diagnosis were correlated with survival by means of univariate analysis; multivariate analysis according to Cox's model was employed to select highly-significant parameters correlated with survival among these variables. Every patient was retrospectively staged according to each clinical and morphological system. Mean survivals were computed for each group on the basis of immunological type, mean value of each prognostic factor, clinical and morphological stage. Survival curves were computed and compared. All prognostic parameters showed a significant relationship with survival, even though p-value differed. Multivariate analysis according to Cox's model has indicated the following variables as significantly correlated with survival: bone marrow plasma cell percentage, degree of lytic bone lesions, hemoglobinemia value, and serum levels of beta 2-microglobulin. Each clinical and morphological staging system, as well as immunological types and mean value of single prognostic parameters, have divided patients into separate groups with significant differences in mean survival and in survival curves. All of these factors could be taken into account for correct prognostic evaluation, and, if they were applied in different steps of diagnosis and therapy, it would be possible to study the MM patient under different perspectives, in order to have a more complete picture of the disease and of the patient.

Adult↗
PubMed1998

Computer-assisted sperm head morphometry analysis (ASMA) of cryopreserved ram spermatozoa.

Normal sperm morphology has been shown to be indicative of male fertility; however, subjective methods of assessing morphology are highly variable. Computer-assisted sperm morphometry analysis (ASMA) has been developed for the objective analysis of sperm head dimensions. Developing applicable protocols for sperm head morphometry analysis increases the efficiency of these systems. The objective of the current study was to develop accurate methods for employing ASMA of ram sperm heads. Staining methods, optimal sperm sample numbers microscopic magnification and sampling variation within and between technicians were assessed. Frozen semen from 10 fertile rams was thawed and prepared on slides for morphometric analysis. Staining spermatozoa with hematoxylin and rose bengal stains yielded the best results. Ram sperm head morphometry was accurately evaluated on at least 100 spermatozoa at x 40 objective magnification. Using these techniques, a sample could be analyzed in approximately 3 min. No significant differences in sperm head measurements were detected between 2 technicians. The system properly recognized and digitized ram spermatozoa 95% of the time. The morphometric measurements of sperm heads for all rams were as follows: length = 8.08 microns, width = 4.80 microns, width:length ratio = 0.59, area = 29.13 micron 2 and perimeter = 23.93 microns. The mean within analysis coefficients of variation for all individual analyses and parameters ranged from 4.8% for length to 6.0% for area. The variation between replicate analysis was 2.4% or less for both technicians. When applying proper sample preparation and analysis procedures no differences in measurements or variation were observed between the 2 system operators.

Animals↗
PubMed1995

The computed axial tomography of the brain in protein energy malnutrition.

Forty consecutive new cases of protein energy malnutrition were evaluated clinically and biochemically; in addition, the brain morphology was assessed by computed tomography within 24 hours of admission. Cerebral shrinkage was shown in six of 14 (42.9%) cases of marasmus, ten of 14 (71.4%) cases of kwashiorkor, and 11 of 12 (91.7%) cases of marasmic-kwashiorkor. Ventricular dilatation was demonstrated in 57.1% of marasmus cases, 71.4% of kwashiorkor cases and 91.7% of patients suffering from marasmic-kwashiorkor. However, none of the subjects studied showed any changes in the brain stem or cerebellum. Only ten returned 2 months after nutritional rehabilitation for repeat tomograms. None of these repeat tomograms showed any residual morphological changes. The study demonstrated that the brain is affected in all types of malnutrition, albeit in different proportions, but these changes are completely reversible.

Brain↗
PubMed1996

Quantitative immunohistochemistry of factor VIII-related antigen in breast carcinoma: a comparison of computer-assisted image analysis with established counting methods.

Microvessel density in the area of the most intense neovascularization in invasive breast carcinoma is reported to be an independent prognostic factor. The established method of enumeration of microvessel density is to count the vessels using an ocular raster (counted microvessel density [CMVD]). The vessels were detected by staining endothelial cells using Factor VIII-related antigen. The aim of the study was to compare the CMVD results with the percentage of factor VIII-related antigen-stained area using computer-assisted image analysis. A true color red-green-blue (RGB) image analyzer based on a morphologically reduced instruction set computer processor was used to evaluate the area of stained endothelial cells. Sixty invasive breast carcinomas were included in the analysis. There was no significant correlation between the CMVD and the percentage of factor VIII-related antigen-stained area (Spearman correlation coefficient = 0.24, confidence interval = 0.02-0.46). Although high CMVD was significantly correlated with poorer recurrence free survival (P = .024), percentage of factor VIII-related antigen-stained area showed no prognostic value. Counted microvessel density and percentage of factor VIII-related antigen-stained area showed a highly significant correlation with vessel invasion (P = .0001 and P = .02, respectively). There was no correlation between CMVD and percentage of factor VIII-related antigen-stained area with other prognostic factors. In contrast to the CMVD within malignant tissue, the percentage of factor VIII-related antigen-stained area is not suitable as an indicator of prognosis in breast cancer patients.

Breast Neoplasms↗
PubMed2003

Metopic synostosis: Defining the temporal sequence of normal suture fusion and differentiating it from synostosis on the basis of computed tomography images.

Only the metopic suture normally fuses during early childhood; all other cranial sutures normally fuse much later in life. Despite this, metopic synostosis is one of the least common forms of craniosynostosis. The temporal sequence of normal physiologic metopic suture fusion remains undefined and controversial. Therefore, diagnosis of metopic synostosis on the basis of computed tomography images alone can prove misleading. The present study sought to determine the normal sequence of metopic suture fusion and characterize both endocranial and ectocranial suture morphology. An analysis of computed tomography scans of 76 trauma patients, ranging in age from 10 days to 18 months, provided normative craniofacial data that could be compared to similar data obtained from the preoperative computed tomography scans of 30 patients who had undergone surgical treatment for metopic synostosis. Metopic suture fusion was complete by 6 to 8 months in all nonsynostotic patients, with initiation of suture fusion evident as early as 3 months of age. Fusion was found to commence at the nasion, proceed superiorly in progressive fashion, and conclude at the anterior fontanelle. Although an endocranial ridge was not commonly seen in synostotic patients, an endocranial metopic notch was virtually diagnostic of premature suture fusion and was seen in 93 percent of synostotic patients. A metopic notch was not seen in any nonsynostotic patient. The morphologic and normative craniofacial data presented permit diagnosis of metopic synostosis based on computed tomography images obtained beyond the normal fusion period.

Cranial Sutures↗
PubMed1993

Analysis of morphology and gait function after intraarticular calcaneal fracture.

Open reduction and internal fixation is suggested by an increasing number of investigators as preferable treatment of displaced intraarticular calcaneal fractures. Assuming that quasianatomical reduction coincides with adequate function, many surgeons rely on morphological parameters (standard radiography, computed tomography) to demonstrate the effectiveness of surgery by achieving an optimum restoration of calcaneal geometry and joint surfaces. In order to correlate morphologic parameters and functional assessment, a prospective study was performed on 45 patients after surgical treatment of intraarticular calcaneal fractures using standard radiographic and computed tomographic scores, clinical evaluation, and gait analysis (dynamic pedography). Mean follow-up time after reconstruction was 23 months (range 18-50). Although clinical evaluation and assessment of gait function corresponded well with each other, radiographic scores showed a poor to moderate correlation with functional evaluation (r = 0.29-0.62); this was probably due to the missing analysis of soft tissue parameters. The comparison of clinical results and gait parameters with the individual radiographical parameters allowed us to identify those factors, with the greatest influence seen on the functional prognosis (i.e., calcaneal width, arthrosis in the neighboring joints). Morphologic analysis after calcaneal reconstruction based on radiographic techniques cannot predict subsequent function or substitute for functional assessment. However, it does allow for practical conclusions for surgical strategy in primary osseous reconstruction or secondary corrections.

Activities of Daily Living↗
PubMed2003

Morphological relationship between the cranial base and dentofacial complex obtained by reconstructive computer tomographic images.

The aims of this study were to investigate the relationships between the cranial base, including the glenoid fossa and maxillofacial morphology, obtained by three-dimensional (3D) computed tomography (CT). The specimens were 45 Skeletal I and Skeletal II dry skulls of modern Japanese males without marked crowding, anterior crossbite, or maxillofacial asymmetry, which had been preserved in the Tokyo University Museum. To examine the differences in the cranial base and maxilla between two groups classified by the median value of N line-A [N defined as a perpendicular line to Frankfort horizontal (FH) through point N, and N line-A as the distance between N and point A]. The specimens with an N-A line less than 1.5 mm were classified as the small group, and those with an N line-A more than 1.5 mm as the large group. Correlation coefficients showed that S-SE was positively related to N-Ba, S-N, S-Ba, and angleFH to S-Ba, and negatively related to SE-N. Ba-X, Ba-Y and Gf-X showed positive correlation with S-Ba and angleFH to S-Ba. For the small group S-SE was longer, angleFH to S-Ba was larger, and Ba-X, Gf-X, A-X, ANS-X, and PNS-X located more posterior and in addition more inferior in ANS-Y. The evidence suggests that S-SE, which is a main component factor of the anterior cranial base, and the antero-posterior position of glenoid fossa, is related to the position of the maxilla. The length and inclination of the posterior cranial base, which is related to Ba, influenced the position of the glenoid fossa.

Adult↗
PubMed2005

A feasibility study of contrast enhancement of acute myocardial infarction in multislice computed tomography: comparison with magnetic resonance imaging and gross morphology in pigs.

INTRODUCTION: Late enhancement magnetic resonance imaging (MRI) of myocardial infarction (MI) is clinically established. There are no reports on MI assessment using state-of-the-art multislice CT technology. For this reason, animal experiments were conducted to examine the applicability of contrast-enhanced ECG-gated multislice computed tomography (MSCT) for the detection of acute MI. The results were correlated with MRI and postmortem tissue staining. MATERIAL AND METHODS: Acute MI was induced in 14 pigs by balloon occlusion of the LAD. In 8 animals, the LAD was reperfused after 45 minutes. In 6 animals, the LAD was permanently blocked. MR imaging was performed 15 minutes after the administration of 0.2 mmol Gd-DTPA/kg/bodyweight. Subsequently, 16-slice MSCT was performed at various timepoints after injecting 120 mL of iodinated contrast medium. 2,3,5-Triphenyltetrazolin-chloride (TTC) staining was acquired for all hearts investigated. Correlation analysis was applied to compare the area of MI derived from MRI, MSCT, and TTC. The reperfused infarcts were compared with the nonreperfused infarcts using an unpaired t test. RESULTS: : Mean infarct area as measured by TTC staining was 18.3% +/- 7.8% of the left ventricular area. Good correlation of the spatial extent of the infarcted area was found for TTC and MRI as well as for TTC and MSCT data obtained 5 minutes postcontrast injection. MSCT imaging demonstrated a significant difference in density (P < 0.001) between nonreperfused (47.0 +/- 6.6 HU) and reperfused (116.4 +/- 19.8 HU) infarction. CONCLUSION: In our pilot study, contrast-enhanced MSCT was feasible to assess myocardial viability in pigs. MSCT also affords differentiation of nonreperfused and reperfused acute MI. MI sizes derived from MSCT imaging correlate well to those obtained with MRI and TTC.

Animals↗
PubMed1992

Estimating the electrotonic structure of neurons with compartmental models.

1. A procedure based on compartmental modeling called the "constrained inverse computation" was developed for estimating the electrotonic structure of neurons. With the constrained inverse computation, a set of N electrotonic parameters are estimated iteratively with use of a Newton-Raphson algorithm given values of N parameters that can be measured or estimated from experimental data. 2. The constrained inverse computation is illustrated by several applications to the basic example of a neuron represented as one cylinder coupled to a soma. The number of unknown parameters estimated was different (ranging from 2 to 6) when different sets of constraints were chosen. The unknowns were chosen from the following: dendritic membrane resistivity Rmd, soma membrane resistivity Rms, intracellular resistivity Ri, membrane capacity Cm, dendritic membrane area AD, soma membrane area As, electrotonic length L, and resistivity-free length, rfl (rfl = 2l/d1/2 where l and d are length and diameter of the cylinder). The values of the unknown parameters were estimated from the values of an equal number of known parameters, which were chosen from the following: the time constants and coefficients of a voltage transient tau 0, tau 1, ..., C0, C1, ..., voltage-clamp time constants tau vc1, tau vc2, ..., and input resistance RN. Note that initially, morphological data were treated as unknown, rather than known. 3. When complete morphology was not known, parameters from voltage and current transients, combined with the input resistance were not sufficient to completely specify the electrotonic structure of the neuron. For a neuron represented as a cylinder coupled to a soma, there were an infinite number of combinations of Rmd, Rms, Ri, Cm, AS, AD, and L that could be fitted to the same voltage and current transients and input resistance. 4. One reason for the nonuniqueness when complete morphology was not specified is that the Ri estimate is intrinsically bound to the morphology. Ri enters the inverse computation only in the calculation of the electrotonic length of a compartment. The electrotonic length of a compartment is l[4 Ri/(dRmd)]1/2, where l and d are the length and diameter of the compartment. Without complete morphology, the inverse computation cannot distinguish between a change in d or l and a change in Ri. Even when morphology is known, the accuracy of the Ri estimate obtained by any fitting procedure is affected by systematic errors in length and diameter measurements (i.e., tissue shrinkage); the Ri estimate is inversely proportional to the length measurement and proportional to the square root of the diameter measurement.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1980

[Computer tomography for gynaecological carcinomas (authors's transl)].

The morphology of gynaecological cancers was studied by computer tomography in 220 ovarian and uterine carcinomas. The value of the method with regard to staging and diagnosis is discussed. Non-invasive computer tomography for gynaecological cancers is indicated. 1. In order to obtain significant information regarding the extent of the tumour and its regional metastases. 2. In order to reduce the need for other invasive diagnostic measures. 3. For improving treatment by interdisciplinary procedures, particularly with respect to planning of radiation therapy. 4. For the early recognition of recurrences and for objective evaluation of the result of treatment.

Female↗
PubMed1996

Inhibitory effects of isoproterenol on PAF-induced endothelial cell permeability and morphological changes.

Using a model to study vascular permeability under hydrostatically perfused bovine pulmonary artery endothelial cell (EC) monolayers and a software to automatically analyse cell morphological parameters in a computer image workstation, the effects of isoproterenol (IPN) on platelet-activating factor (PAF)-induced changes in EC monolayer permeability and cell morphological parameters were studied. Albumin has the fortifying effect on endothelial barrier function. After treatment of EC monolayer with 10(-8) mol/L PAF, trans-monolayer permeability increased, cell surface area decreased, and intercellular space enlarged. As pretreatment with 10(-4) mol/L IPN, PAF-induced EC permeability increment and morphological changes were blocked. The results suggest that EC contraction and intercellular gap expansion are important mechanisms for PAF-induced high vascular permeability. IPN inhibits the effects of PAF via stabilization of EC morphology and prevention of intercellular gap formation.

Adrenergic beta-Agonists↗
PubMedDate not supplied

[Computed tomography in refined diagnosis of abdominal aortic aneurysm: comparison of radiation therapies versus surgical outcomes and morphological studies of resected abdominal aortic fragments].

The results of computed tomography (CT) was compared with ultrasonographic and angiographic findings in 168 patients. All data of radiation diagnosis of abdominal aortic aneurysms (AAA) were compared with those of operations and morphological studies of the resected fragments of the aortic parts changed due to aneurysms. These comparisons provided a detailed characterization of the potentialities of CT performed on a third-generation unit in the presurgical diagnosis of this abnormality. At the same time, detailed XCT findings (semeiotics of AAA and their complications, such infiltration, dissection, and rupture) are given. The study shows benefits of the refined AAA by applying routine CT. The paper gives a diagnostic algorithm of using radiation studies (ultrasonography, CT, angiography) in the diagnosis of AAA. Third-generation CT units widely used in clinical practice are shown to provide necessary and complete information on the magnitude of AAA. This makes it possible to extend the capacities of timely detection of this abnormality and to make a successful surgical intervention.

Aged↗
PubMed1988

Computer-assisted breast cancer grading.

Morphological tumour differentiation has been shown in numerous studies to give a good prognosis in breast cancer, but as histological grading is based upon a subjective assessment of microscopical appearances, difficulties in consistency and reproducibility are inevitable. A review of the many conventional methods served to highlight a common limitation in their approach; lack of structure. We introduce a new approach which seeks to overcome the problem, by formalizing the methods and identifying aspects which are well suited to computer aided analysis, these being incorporated into a microcomputer system facilitating the collection and appraisal of morphometric data. Within the Information Technology Institute (ITRI) at Brighton Polytechnic a research team is carrying out multidisciplinary work into the elucidation of biological systems. This programme, entitled 'Intelligent Medical Systems', used methods of mathematical signal processing and artificial intelligence, applied to a number of areas, one of which is described in this paper. The aim has been to utilize the inherent skill exercised by the histopathologist in interpreting microscopical images, whilst making quantitization more accurate and reproducible. the system has been developed within a highly structured framework and will have applications in teaching and routine histological analysis. The value of artificial intelligence techniques in the wider issues of this area is discussed.

Artificial Intelligence↗
PubMed1991

A comparison of four new time-domain techniques for discriminating monomorphic ventricular tachycardia from sinus rhythm using ventricular waveform morphology.

Electrical management of intractable tachycardia via implantable antitachycardia devices has become a major form of therapy. Newly advanced methods of ventricular tachycardia detection propose examination of changes in intraventricular electrogram morphology in addition to or in combination with earlier rate-based detection algorithms. Unfortunately, most of the proposed morphology analysis techniques have computational demands beyond the capabilities of present devices or may be adversely affected by amplitude and baseline fluctuations of the intraventricular electrogram. We have designed four new computationally efficient time-domain algorithms for distinguishing ventricular electrograms during monomorphic ventricular tachycardia (VT) from those during sinus rhythm using direct analysis of the ventricular electrogram morphology. All four techniques are independent of amplitude fluctuations and three of the four are independent of baseline changes. These new techniques were compared to correlation waveform analysis, a previously proposed method for distinction of VT from sinus rhythm. Evaluation of these four new algorithms was performed on data from 19 consecutive patients with 31 distinct monomorphic ventricular tachycardia morphologies. Three of the algorithms performed as well or better than correlation waveform analysis but with one-tenth to one-half the computational demands.

Aged↗
PubMed1994

Morphological study of the rostral interstitial nucleus of the medial longitudinal fasciculus in the monkey, Macaca mulatta, by Nissl, Golgi, and computer reconstruction and rotation methods.

We have studied the morphology of silver-impregnated neurons (rapid Golgi technique) in the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF), a center involved in the control of vertical and torsional saccadic eye movements. This morphological study of riMLF neurons in the rhesus monkey was undertaken to further our understanding of the functional circuitry of the oculomotor system. Our study employed Nissl, Golgi, and computer-assisted methods. The cytoarchitectonic boundaries of the riMLF and its relationships to neighboring structures were determined in both Nissl and Golgi preparations. Five (I-V) distinct morphological types of riMLF neurons were distinguished in the Golgi impregnations on the basis of soma size, dendritic size, numbers of primary dendrites, number of dendritic branch points, as well as form, number, and distribution of dendritic appendages. Type I neurons impregnated most frequently and had the most extensive and highly branched dendritic tree. Type II neurons displayed thick dendrites with complex dendritic appendages, but the dendritic tree was much more compact than that of type I cells. Type III and type V cells had fusiform somas and relatively unbranched dendritic trees but differed greatly in size as well as dendritic morphology. The type IV cell was the smallest neuron and had many characteristics of the local interneurons found in other thalamic, subthalamic, hypothalamic and midbrain centers. The type V was the largest neuron, least frequently impregnated, and found only at rostral riMLF levels. Digitized reconstructions of each type of neuron were rotated by the computer, which revealed that the dendritic trees of types I, III, and V occupy a disk-like compartment in the riMLF neuropil. In contrast, the tree of types II and IV occupy a roughly spherical compartment. We suggest that three of the cell types are well suited for specific purposes: type II cells for receiving topographically organized inputs that contain spatial information, type I cells for short-lead burst neuron output to the motor neurons or other premotor centers, and type IV cells for inhibitory inputs to type I cells.

Animals↗