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PubMed1987

Prospective evaluation of prognostic value of morphometry in patients with primary breast cancer.

In a prospective study the predictive value of a multivariate morphometric prognostic index was evaluated in 195 patients with primary breast cancer who had not been treated with any form of chemotherapy or hormonal treatment. The presence or absence of distant tumour recurrence combined with the scores of the prognostic index were compared with the survival curves predicted in a previous study. The value of the presence of lymph node metastases, number of positive nodes, tumour size, mitotic activity index, and oestrogen receptor status in prediction of prognosis were also investigated. In agreement with the results of the previous retrospective study, the prospective use of the index had the strongest predictive prognostic value, followed by the mitotic activity index. Statistical analysis showed that the actual prognoses of 43 of the 195 patients (22%) were more accurately determined by the prognostic index rather than by using the presence of the lymph node metastases as the classifying variable. The prognostic index is consistently reproducible by different technicians; it is a reliable method of predicting distant recurrence of tumour and hence the prognosis of patients with primary breast carcinoma. It provides more prognostic information than the presence of lymph node metastases alone, and the index should be incorporated in routine pathology reports.

Adult↗
PubMed1989

Diamine oxidase plasma activities after treatment with heparin and jejunal morphometry in untreated coeliac disease.

Diamine oxidase plasma concentrations after treatment with heparin were measured and compared with the surface to volume ratio of jejunal biopsy samples assessed by a morphometric technique in patients with untreated and treated coeliac disease and in biopsied controls. As expected, enzyme activity was significantly lower in patients with untreated coeliac disease than in patients on a gluten-free diet and in biopsied controls. No difference was found between treated patients and biopsied controls. There was a significant overall correlation between plasma enzyme activity and surface to volume ratio of jejunal mucosa, although two untreated patients without an overt malabsorption syndrome but with a very low surface to volume ratio had normal enzyme activity. This study shows that in coeliac disease plasma diamine oxidase activity after treatment with heparin does not always mirror the extent of the jejunal lesions, particularly in those patients with minimal or unrelated symptoms who would benefit most from a valid screening test to identify their condition.

Adult↗
PubMed1990

Morphometry of the corpus callosum in monozygotic twins discordant for schizophrenia: a magnetic resonance imaging study.

The corpus callosum (CC) has been the focus of several morphometric studies of patients with schizophrenia, but the results of these studies have been contradictory. In an attempt to improve the reliability of morphometric measurements of the corpus callosum, a computerised image analysis system was used to measure the shape, area, thickness and length of the CC on magnetic resonance imaging (MRI) in 12 pairs of monozygotic twins discordant for schizophrenia (SC). No differences in CC area (anterior, middle, posterior thirds and total), length or vertical thickness of the CC body (at three levels) were demonstrated by t test comparisons of the affected SC and unaffected twins. Statistical analysis of a Fourier expansion series suggested differences in shape between normal and SC cotwins in the second harmonic of the anterior and middle segments and effects of gender on posterior CC shape. These results fail to replicate previous findings of altered length, thickness and area in the schizophrenic CC, but implicate disease-related shape differences in the anterior and middle segment of the corpus callosum and gender-related differences in splenium shape. The disease-related shape distortion suggest ventriculomegaly rather than an intrinsic abnormality of the corpus callosum.

Adult↗
PubMed2002

Morphometry of the corpus callosum in patients with questionable and mild dementia.

Previous studies have shown a reduction in corpus callosum area in advanced Alzheimer's disease, but it is unclear whether callosal atrophy is present in the transitional phase between health and the onset of dementia. The aim of this study was to investigate whether callosal atrophy is present in subjects with questionable and mild dementia and to assess the diagnostic value of callosal measures. In 83 subjects aged 72 to 85 years (33 normal controls, 27 patients with questionable dementia, 23 with mild Alzheimer's disease), magnetic resonance images were recorded and the mid-sagittal callosal area measured. Significant differences were found between normal controls and mild dementia. In subjects with questionable dementia callosal size was intermediate between normal controls and mild Alzheimer's disease. However, callosal measures were unsuitable for diagnostic differentiation between healthy subjects, subjects with questionable dementia, and subjects with mild Alzheimer's disease. The severity of white matter changes did not differ between the groups.

Aged↗
PubMed1975

Application of ultrastructural morphometry to lung biopsy specimens in pulmonary histiocytosis X.

Stereological techniques were applied to an electron microscopic study of biopsy samples from nine human lungs with diffuse pulmonary histiocytosis X, and the results were compared with values for normal lungs. This made possible a morphometric analysis of the tissue changes associated with the measurable abnormalities in gas transfer present in this disease. The small increases in arithmetic mean thickness of the alveolar-capillary membranes appeared insufficient to account for the reduction in gas transfer present. When compared with normal lung, a threefold increase in volumetric fraction of septal intercapillary tissue was found along with a corresponding decrease in septal capillaries. While uniformity of distribution cannot be determined by this method, it appears that abnormalities of blood gas transfer in this disease result primarily from a decrease in the available diffusing surface and the ventilation-perfusion distrubances with which these tissue changes are associated.

Adult↗
PubMed1981

Morphometry of pulmonary arteries from angiograms in chronic obstructive lung disease.

The application of morphometric techniques based on Strahler orders to the study of pulmonary angiograms is described. When the pulmonary arterial tree is ordered by Strahler's method, peripheral branches have the lowest orders and the main pulmonary artery the highest order. The mean diameter of vessels in each order can then be determined. Pulmonary angiograms were obtained from 16 patients, 10 of whom had chronic obstructive lung disease (COLD), the other six having normal angiograms. Six orders of branching were found in vessels of 1 mm diameter or greater, and a plot of log mean diameter versus order from the normal angiograms was linear. The mean diameters of orders 2, 3, and 4 (diameter 2 to 7 mm) from COLD patients were significantly reduced ((p less than 0.01) and the log mean diameter versus order plot was concave upwards. These changes were more marked when TLC was raised than when it was normal. Plots of diameters of vessels from zones of the lung in which the pathology was well advanced (as judged by radiological changes) showed even greater reduction in the middle orders. These changes are probably the result of stretching of vessels in emphysematous lesions and diminution of blood flow from loss of capillary bed.

Adult↗
PubMed1984

Atrophic rhinitis: snout morphometry for quantitative assessment of conchal atrophy.

Morphometric methods, either point counting or semiautomated planimetry, can be applied to photographic or impression prints of sections of the pig snout to measure the extent of conchal atrophy on a continuous scale as a morphometric index. Though relatively time consuming, the technique yields highly repeatable parametric data which do not depend heavily on expert, subjective judgment. It is therefore particularly suitable for quantitative analysis of the effects of experimental treatments or changes in management.

Animals↗
PubMed1987

Endothelial cell morphometry near branch junctions of rabbit aortae.

Endothelial cell morphometric data were gathered from corrosion casts of the aorta and its branches of six New Zealand white rabbits weighing 2-3 kg. The endothelial cell outlines were ditigized to provide cell orientation index (COI) from the equation COI = 2Ms/2M1-1, where 2Ms and 2M1 are the second moments of area about short and long axes of the cell. The COI varies from zero to infinity. The former occurs when cells are symmetrical (e.g., circular) since 2Ms = 2M1 and the latter occurs for a straight line. Large values of COI were found distal to intercostals, lumbars, and the aortorenal junction, and probably reflect relatively stable high shear regions. Values close to zero occur on the flow divider where the shear stress approaches zero. Other values were less predictable and we concluded that while the long axis of the cell appears to indicate flow direction, the shape of the cell does not appear to be a reliable indicator of either tensile forces or shear stress acting in it, but probably reflects a combination of the two.

Animals↗
PubMed2006

Age effects in time estimation: relationship to frontal brain morphometry.

Compared with many other cognitive functions, relatively little is known about time representation in the brain. Recent work shows disrupted timing and time estimation in older adults, although it is unclear whether these effects are the result of normal aging or disease-related processes. The present study examined time estimation in persons across the adult lifespan who were free from significant medical or psychiatric history. Results showed older adults exhibited greater variability in time estimation, but no evidence for systematic acceleration or slowing emerged. This variability was correlated with performance on a variety of cognitive tests including attention, working memory and executive function. Although no relationship emerged between time estimation and EEG indices from central regions, multiple MRI indices were significantly correlated with time estimation. Stepwise regression showed volume of the supplementary motor area predicted variability in time estimation. These results indicate that healthy aging is associated with altered time estimation and suggest that changes in frontal brain regions mediate these effects.

Adolescent↗
PubMed1996

Hippocampal MR imaging morphometry by means of general pattern matching.

PURPOSE: To determine the repeatability and validity of a pattern-matching method for the segmentation and measurement of hippocampi on magnetic resonance (MR) images. MATERIALS AND METHODS: Comparable two-dimensional MR images obtained in 18 subjects (nine healthy control subjects [six men, three women; aged 24-54 years] and nine patients with schizophrenia [six men, three women; aged 22-61 years]) were twice segmented manually and twice segmented by using pattern matching with digital atlas transformation. The atlas transformation was accomplished in two steps: global followed by local matching. Global matching was performed with use of landmarks; local matching was performed with use of a viscous fluid model. RESULTS: The mean percentage of difference between two atlas-based measurements was 1.33% +/- 1.23 (+/- standard deviation); that between two manual measurements was 4.67% +/- 4.71. The validity of the atlas transformation measurements was demonstrated by means of the high correlation (intraclass correlation coefficient = .96) with manual segmentation measurements. Schizophrenic hippocampal areas tended to be smaller; however, no differences in hippocampal shape were found between patients with schizophrenia and patients with control subjects. CONCLUSION: General pattern matching of a digital brain atlas to an individual MR image is a mathematically robust method of measurement that is reproducible and less variable than manual measurement.

Adult↗
PubMed2000

Pelvic CT morphometry in Down syndrome: implications for prenatal US evaluation--preliminary results.

PURPOSE: To characterize pelvic morphometric differences in patients with and those without Down syndrome by using computed tomography (CT) and to determine useful indexes for ultrasonographic (US) evaluation. MATERIALS AND METHODS: Pelvic CT scans in seven patients with Down syndrome and in 27 patients without Down syndrome were reviewed. Iliac angle, iliac length, sacroiliac joint angle, and anterior iliac wing separation were measured at superior, middle, and inferior transverse sacral levels. The effects of chromosomal status and transverse level were evaluated statistically. RESULTS: Significant differences were found for mean iliac angle (P < .007) and length (P < .005) between patients without Down syndrome (angle, 75 degrees; length, 8.4 cm) and those with Down syndrome (angle, 82 degrees; length, 7.5 cm). Depending on the level of measurement, variations in iliac angle between patients without and those with Down syndrome were as much as 13 degrees and 15 degrees, respectively, and variations in length were as much as 1.6 cm and 0.9 cm, respectively. The greatest differences were at the middle sacral level. Sacroiliac joint angle and the anterior iliac wing separation were not different between groups. CONCLUSION: Patients with Down syndrome had a larger mean iliac angle and a shorter mean iliac length. The most pronounced differences were at the middle sacral level, which suggests that this may be the optimal level for measuring these parameters at prenatal US.

Down Syndrome↗
PubMed1997

Morphometry and strain distribution in guinea pig duodenum with reference to the zero-stress state.

The aim of the present study is to determine the distribution of residual circumferential strains along the duodenum in anesthetized guinea pigs. A silicone elastomer was allowed to harden in the duodenal lumen under a pressure of 0.7 kPa. The duodenum was excised with the cast and photographed. The zero-stress state was obtained by cutting rings of duodenum radially. The geometric configuration at the zero-stress state is of fundamental importance, because it is the basic state with respect to which the physical stresses and strains are defined. A basic piece of information is the way the tangent vector rotates from one end of the circumference to the other. In the duodenum at zero-stress state, the total rotation of the tangent from one tip to the other is -500 to -850 , with the lowest absolute value in the proximal duodenum. In other words, the duodenum usually turns itself inside out on changing from a loaded state to the zero-stress state. The serosal circumference, the duodenal wall thickness, and the ratio of wall thickness to mucosal circumference decreased in the distal direction. In the pressurized state, the serosal Cauchy strain was tensile and increased in the distal direction; the mucosal Cauchy strain was compressive in the proximal half of the duodenum and tensile in the distal half. The large circumferential residual strains must be taken into account in a study of physiological problems in which the stresses and strains are important, e.g., the bolus transport function.

Animals↗
PubMed1982

Morphometry of right ventricular hypertrophy induced by strenuous exercise in rat.

Effects on the myocardium, particularly those structural properties of the capillary network relevant to tissue oxygenation, were studied morphometrically in rats subjected to a severe running program. Physical conditioning produced a 31% increase in right ventricular weight and only a 12% increase in the weight of the left ventricle. Quantitative analysis of right ventricular myocardium demonstrated relative decreases in capillary luminal volume density (-27%) and capillary luminal surface density (-20%) and an increase in the average maximum distance from the capillary wall to the mitochondria of myocytes (14%). In contrast, the contractile mass expanded in proportion to the growth of the ventricle through augmentation of the cross-sectional area (17%) and length (19%) of the average myocyte. Evaluation of the subcellular constituents of myocytes showed no change in the mitochondria-to-myofibril volume ratio. In conclusion, the capillary bed controlling oxygen availability, diffusion, and transport suggests that excessive physical activity may be detrimental to the myocardium.

Animals↗
PubMed1983

Medial morphometry and mechanics of sequential rabbit ear arteries and myograph ring segments.

The medial structure of three different branching orders of arteries in the rabbit ear was studied to assess the possible significance with regard to mechanical behavior determined with the in vitro myograph. The central ear artery, its main side branch, and a terminal branch were fixed while dilated in situ at 100 mmHg; this resulted in internal diameters of 960, 456, and 251 micron, respectively. The average ratio of medial thickness to internal diameter was 0.0293 for arteries in situ and 0.0487 for arterial rings in vitro. Measurements undertaken for the determination of smooth muscle (SM) stress included the percentage of SM in the media (74%) and the pitch of SM (0.89 degrees). These parameters were not significantly different in the three various-sized arteries or for the two myographs. Stereological estimates of SM cell volume, length, and diameter were based on counts of SM nuclei and their length. In evaluating the ring preparation of the vessel myographs, the damage due to the wires (20%) and cut edges (6.4%) was considered. The maximum active SM stress was approximately the same in the different-sized vessels with an average value of 3.14 X 10(5) N/m2. Since this stress is comparable to measurements made by others on different mechanical apparatus and consistent for the three arterial orders, these in vitro myographs should allow for valid comparison of arterial mechanical properties over the size range studied.

Animals↗
PubMed1985

Left ventricular failure induced by myocardial infarction. II. Tissue morphometry.

Three days after myocardial infarction involving 57% of the left ventricle in rats, the viable tissue of the left ventricle expanded 29%, whereas myocardial hypertrophy in the right ventricle was 19%. To determine whether tissue oxygenation in the hypertrophied ventricles was supported by a proportional growth of the capillary network, morphometric analysis was used to measure capillary luminal volume and surface densities and the diffusion distance for O2. The volume fraction of capillary lumen and the luminal surface of capillaries, related to O2 availability and diffusion, were altered by -21 and -19%, respectively, in the left ventricle and by -23 and -20%, respectively, in the right ventricle. The path length for O2 transport was found to be increased by 12 and 15% in the left and right ventricle, respectively. In contrast, myocyte mass expanded in proportion to tissue growth in the left ventricle and exceeded tissue growth by 5% in the right ventricle. Myocyte mitochondria and myofibrils both grew in proportion to the cells, so that their volume ratio was not changed in either ventricle. The relatively inadequate adaptation of the capillary vasculature suggests that hypertrophy after severe myocardial infarction may initially leave the heart more vulnerable to additional ischemic episodes.

Adenosine Triphosphate↗