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Results for “morphometry”

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PubMed2000

Preoperative severity of emphysema predictive of improvement after lung volume reduction surgery: use of CT morphometry.

STUDY OBJECTIVE: To determine how the volume and severity of emphysema measured by CT morphometry (CTM) before and after lung volume reduction surgery (LVRS) relates to the functional status of patients after LVRS. DESIGN: A histologically validated CT algorithm was used to quantify the volume and severity of emphysema in 35 patients before and after LVRS: total lung volume (TLV), normal lung volume (< 6.0 mL gas per gram of tissue), volume of mild/moderate emphysema (ME; 6.0 to 10.2 mL gas per gram of tissue), volume of severe emphysema (> 10.2 mL gas per gram of tissue), surface area/volume (SA/V; meters squared per milliliter), and surface area (SA; meters squared). Outcome parameters included maximal cardiopulmonary exercise (CPX) performance in 21 patients and routine pulmonary function in all patients. We hypothesized that baseline CTM parameters predict response to LVRS and that the change in these parameters may offer insight into mechanisms of improvement. PATIENTS AND INTERVENTION: Thirty-five patients with severe emphysema who had successful LVRS. RESULTS: The significant decrease in TLV following LVRS was entirely accounted for by a decrease in severe emphysema. The SA/V and the SA both increased significantly following LVRS. The change in maximal CPX in watts following surgery correlated significantly with baseline values of severe emphysema (r = 0.60), which was collinear with TLV, and SA/V. The change in diffusing capacity of the lung for carbon monoxide revealed a significant positive linear relationship with preoperative severe emphysema (r = 0.37) and a negative relationship with ME (r = -0.37). Change in watts revealed a strong relationship with changes in severe emphysema (r = -0.75) and weaker but significant relationships with change in TLV, ME, SA/V, and SA. Other measures of pulmonary function revealed significant albeit less dominant relationships with baseline CTM and change in these indexes. CONCLUSION: Using CTM, we have identified a close relationship between baseline severe emphysema, or change in severe emphysema, and the improvement in CPX after LVRS. These observations support a potential role of CTM in future clinical trials for predicting responders to LVRS and identifying mechanisms of improvement.

Algorithms↗

PubMed1999

Selective nuclear morphometry as a prognostic factor of survival in renal cell carcinoma.

In the present study, we sought to determine the predictive value of selective nuclear morphometry (SNM) for patient outcome in renal cell carcinoma (RCC). Tumor samples of 140 renal adenocarcinomas diagnosed and treated with radical nephrectomy and hilar lymphadenectomy between 1970 and 1988 with a minimum follow up of 5 years in all the cases were studied by SNM. The morphometric analysis was performed in the most malignant tumor selected zone. Selection was based on cytological criteria including nuclear grade. Nuclear morphometric features analyzed were: area, perimeter, major diameter, major and minor diameter of the equivalent ellipse, volume of the equivalent ellipse and sphere, circumference diameter, and shape factors. The results showed that in the selected zone tumor nuclei were larger than in the zones selected at random. There was an inverse correlation between morphometric parameters and survival and a direct one between tumoral grade and stage. Tumors of the long-term survival group of patients presented nuclei with smaller morphometric measurements than tumors of short term survival group, with significant differences between them (p < 0.05). In the survival analysis carried out by the Kaplan-Meier method significant differences existed between different groups formed from break point for: area, perimeter, major diameter, major and minor diameter of the ellipse, volume of the ellipse and sphere, circumference diameter and perimeter shape factor. In the multivariate analysis carried out by the Cox method, the feature with the most predictable value related to survival, was the tumor stage. Morphometric value with the highest punctuation in the test was major nuclear diameter. The rest of the morphometric values (except elliptic shape factor and elongation factor) were also significant but they did not improve prognostic information of the major nuclear diameter. SNM offers a useful aid in a more objective grading of RCC. Multivariate Cox analysis revealed additional value of karyometry to tumor stage. SNM can be a useful tool for stratification of patients with RCC.

Adolescent↗

PubMed2005

Genetic contributions to human gyrification: sulcal morphometry in Williams syndrome.

Although gyral and sulcal patterns are highly heritable, and emerge in a tightly controlled sequence during development, very little is known about specific genetic contributions to abnormal gyrification or the resulting functional consequences. Williams syndrome (WS), a genetic disorder caused by hemizygous microdeletion on chromosome 7q11.23 and characterized by abnormal brain structure and striking cognitive (impairment in visuospatial construction) and behavioral (hypersocial/anxious) phenotypes, offers a unique opportunity to study these issues. We performed a detailed analysis of sulcal depth based on geometric cortical surface representations constructed from high-resolution magnetic resonance imaging scans acquired from participants with WS and from healthy controls who were matched for age, sex, and intelligence quotient, and compared between-group differences with those obtained from a voxel-based morphometry analysis. We found bilateral reductions in sulcal depth in the intraparietal/occipitoparietal sulcus (PS) in the brains of participants with WS, as well as in the collateral sulcus and the orbitofrontal region in the left hemisphere. The left-hemisphere PS in the WS group averaged 8.5 mm shallower than in controls. Sulcal depth findings in the PS corresponded closely to measures of reduced gray matter volume in the same area, providing evidence that the gray matter volume loss and abnormal sulcal geometry may be related. In the context of previous functional neuroimaging findings demonstrating functional alterations in the same cortical regions, our results further define the neural endophenotype underlying visuoconstructive deficits in WS, set the stage for defining the effects of specific genes, and offer insight into genetic mechanisms of cortical gyrification.

Adolescent↗

PubMed1978

Ultrastructural morphometry of sparsely granulated prolactin cell adenomas of the human pituitary.

Fifteen sparsely granulated prolactin-producing adenomas and 10 nontumourous adenohypophyses, removed by surgical hypophysectomy, have been studied using morphometry at the electron microscopic level. Compared to non-tumourous prolactin cells, sparsely granulated adenomatous prolactin cells showed a significant decrease in diameter and volume density of secretory granules and an increased volume density of rough-surfaced endoplasmic reticulum and Golgi apparatus. The volume density of mitochondria remained unchanged. These results indicate that the cells of the adenoma are in a highly active functional state. It appears that the equilibrium between hormone synthesis, storage and release is altered in adenomatous prolactin cells.

Adenoma↗

PubMed1996

Quantification of normal head morphometry of stallion spermatozoa.

The heads of stallion spermatozoa were analysed by computer automated sperm head morphometry and the morphometric values of the major subpopulations of sperm heads were assessed. The criteria for normal dimensions of stallion sperm heads are proposed based on the analysis of these measurements. Semen samples were collected from 10 fertile and 10 subfertile stallions, processed by a standard method, smeared onto microscope slides and stained using haematoxylin. At least 200 properly digitized sperm heads were analysed from each stallion. The measurements for length, width, area, perimeter and width/length were recorded for each stallion. All sperm head measurements were placed in a statistical database and multivariate cluster analysis performed. Mean measurements for all parameters of the major clusters of fertile and subfertile stallions were compared by analysis of variance. The ranges of the values of the major clusters of fertile stallions were applied to all stallions to determine the percentage of normal sperm heads for each stallion. The mean values for length, width, area and perimeter in the major cluster of sperm head dimensions of fertile stallions were significantly different from those of the subfertile stallions (P < 0.001). The range of values of the major cluster of fertile stallions was length = 4.9-5.7 microns, width = 2.5-3.0 microns, width/length = 0.45-0.59, area = 10.3-12.1 microns2, and perimeter = 12.9-14.2 microns. On the basis of these values, a significantly (P < 0.001) higher percentage of normal sperm heads were found in the fertile group than in the subfertile group of stallions (52% versus 19%).

Analysis of Variance↗

PubMedDate not supplied

Characterization of Rhodnius neglectus from two regions of Brazil using isoenzymes, genitalia morphology and morphometry.

Among the triatomines considered as secondary in the epidemiology of Chagas disease, Rhodnius neglectus is frequently captured in artificial ecotopes, especially peridomiciliary ones, rarely producing colonies indoors. Nevertheless, the presence of breeding colonies in houses was unquestionably demonstrated in some areas of the State of Goiás, Brazil. Previous isoenzyme comparisons of this species with morphologically close triatomines, such as R. prolixus, R. robustus or R. nasutus, did not produce definitive conclusions because of doubt about the geographical origin of the R. neglectus. We present here, for the first time, the isoenzyme profile of topotypes of R. neglectus. In addition, wild caught specimens from the type locality, Uberaba (Minas Gerais, Brazil), were compared to wild caught specimens from Jaraguá (Goiás, Brazil), where R. neglectus is more frequently reported invading houses. We used isoenzyme, morphology and morphometry analysis. Neither morphological nor enzymatic differences were found between areas, but metric, size-related divergence was evidenced between them.

Animals↗

PubMed2000

Three-dimensional computer morphometry of the maxilla and face in infants with Pierre Robin sequence--a comparative study.

OBJECTIVE: To analyze the morphology of the maxillary crest in infants with Pierre Robin sequence using an anthropometric coordinate system and to compare the data with those of healthy infants. SETTING: The study was performed at a craniofacial center servicing a large geographic area. PARTICIPANTS: The study involved eight infants aged 1-28 days (average, 7 days) with an established diagnosis of Pierre Robin sequence and six healthy infants aged 1-43 days (average, 22 days). MAIN OUTCOME MEASURES: Physical models of the maxilla and face obtained by alginate replication were analyzed by computer morphometry yielding the three-dimensional topology of the maxillary crest. RESULTS: The maxillary crest of children with Pierre Robin sequence shows an increased inclination relative to the transverse plane (30 +/- 3.9 degrees) as compared with that of healthy infants (20 +/- 2.9 degrees). The maxillary crest of the patients is shortened in the sagittal direction by comparison with healthy controls. CONCLUSIONS: The increased inclination of the maxilla in infants with Pierre Robin sequence may aggravate the retroposition of the mandible and may thus be a pathogenetic factor contributing to the severe respiratory problems.

Alginates↗

PubMed2004

Spatial structuring of Triatoma infestans (Hemiptera, Reduviidae) populations from northwestern Argentina using wing geometric morphometry.

Wing geometric morphometry was used to study the spatial structuring of populations of Triatoma infestans from different villages, ecotopes, and sites within a village in northwestern Argentina. A total of 308 male and 197 female wings of T. infestans collected from peridomestic and domestic ecotopes in March 2000 was analyzed. On average, female bugs had a significantly larger wing size than males. Triatomines collected from domiciles or structures associated with chickens had larger wings than bugs collected from goat or pig corrals. The wing size of bugs did not differ significantly between villages. Discriminant analyses of wing shape showed significant divergence between villages, ecotopes, and individual collection sites. The study of metric variation of males between sites belonging to the same ecotope also revealed significant heterogeneity. Indeed, within the same section of the village the difference between two goat corrals was sometimes greater than that between neighboring goat and pig corrals. Thus, morphometric heterogeneity within villages may be the result not only of ecotope and host associations, but also of physical isolation between subunits. The strong structuring of T. infestans populations in the study area indicates that recolonization could be traced back to a small geographic source.

Animals↗

PubMed1986

The size and number of Langerhans islets correlated with their endocrine function: a morphometry on immunostained serial sections of adult human pancreases.

Surgical and autopsy specimens of normal pancreas from three human adults were submitted to morphometry of Langerhans islets and so-called extra insular islet cells, by measuring the islet radii on serial sections immunostained for either insulin or glucagon. All the islets contained in a test volume were measured including single cells, and the distribution of their radial sizes was studied. It was found that the distribution of islets was strongly skewed and continuous, with the majority of islets having radial values near to the minimum. From the fact that only one peak was found in the distribution curve, it is concluded that in spite of the distinction previously made between islets of Langerhans and so-called extra-islet cells, they are in fact both part of a continuous distribution. Moreover, the Weibull function, assumed as the theoretical distribution, fit well with the empirical histograms, giving support for the contention of continuous distribution with a single peak. Although the small islets account for a majority of the number of islets, they account for only a very small percentage of the islet volume. This is thought to indicate that the bulk of the endocrine functions of the pancreas are carried out by large islets, whereas the so-called extra-islet cells are likely to be their precursors. With regard to the cellular structure of the islets, it was found that the smaller the islet, the smaller the percentage of islets containing A cells, with the vast majority of cells in the smallest islets (often single cells) being B cells.

Adult↗

PubMed1990

Dose dependency of intratracheal elastase-induced changes in pressure volume curve and morphometry in rat lungs.

We studied the dose-dependency of the lung pressure-volume curve (n = 37) and morphometry (n = 30) with intratracheally administered elastase. Four weeks after elastase was instilled at dosages of 20 (EL-20), 40, 80, and 100 U/100 g wt., chord compliance between 50 and 70% of total lung capacity (TLC) (C50-70) and that between 80 and 100% TLC (C80-100) were measured. After a significant initial reduction, the weight of the EL-80 group recovered to the control level, whereas the weight curve of the EL-100 significantly decreased below that of the EL-80. Lung volumes of all the elastase-treated groups were significantly larger than those of control. Air-filled lung volumes monotonously increased when the elastase dose was increased from 20 to 80 U/100 g wt. In contrast lung volume of the EL-100 was significantly lower than that of the EL-80. On the other hand, liquid-filled lung volumes monotonously increased from 20 to 100 U/100 g wt. C80-100 was significantly smaller in the EL-100 than in the EL-80. The mean linear intercept increased and alveolar surface area decreased monotonously over the dose range tested. We conclude that there is a critical dose of elastase below which lung volume is increased and above which the increase is suppressed when elastase is administered intratracheally to Wistar rats.

Animals↗

PubMed2003

A comparison between pre- and posthibernation morphometry, hematology, and blood chemistry in viperid snakes.

Snakes from temperate climates are often made to hibernate in zoos to stimulate reproduction. Unfortunately, deaths have occurred during and after hibernation. This study evaluated the health status, pre- and posthibernation, of 31 adult viperid snakes. It included morphometric measurements, hematology, and blood chemistry. No differences were seen in body weights and weight to length ratios between pre- and posthibernation examinations, suggesting that the overall condition of the snakes did not change. No differences were seen in hematologic and blood chemistry parameters, except that bile acids (3alpha-hydroxybile acids) decreased, the implications of which are unknown. Three individuals had markedly high plasma uric acid levels posthibernation; of these, two individuals died from extensive visceral gout and one recovered with fluid therapy. Viperid snakes should be clinically healthy, well hydrated, and in good body condition when they are put into hibernation. They should be maintained in an environment with sufficient humidity and should have access to water. Blood samples should be collected on arousal for measuring plasma uric acid levels. Changes in morphometry, hematology, and blood chemistry appear to be abnormal and should be investigated thoroughly.

Animals↗

PubMedDate not supplied

Foot and ankle ligament morphometry.

This study primarily measured and established a morphometric spectrum of cross-sectional areas for foot and ankle ligaments with the use of a new freeze-fracture technique that was independent of ligament cross-sectional shape. Ligament morphometry measurements were made on a total of 121 bone-ligament-bone preparations that were harvested from 26 fresh (unembalmed) male cadaver feet. We used the traditional digital caliper method to measure length and the freeze-fracture technique to measure cross-sectional area. Cross-sectional area values ranged from 21.36 to 170.48 mm(2) and length values from 5.01 to 37.45 mm. In addition, area-to-length ratios ranged from 0.60 to 27.02 mm. Compared with the freeze-fracture technique, the digital caliper method, which assumed that ligament cross-sectional shape was rectangular, resulted in an approximately 35% difference in cross-sectional area.

Adult↗

PubMed1995

Morphological evaluation of cyclophosphamide testicular toxicity in rats using quantitative morphometry of spermatogenic cycle stages.

The testicular toxicity of cyclophosphamide (Cp) in rats was evaluated by quantitative morphometry of spermatogenic cycle stages. Nine-week-old male Sprague-Dawley rats in Group 1 were given a single oral administration of 100 mg/kg of Cp, and were sacrificed at 1, 7, 14 and 21 days thereafter. Rats in Group 2 were orally given 100 mg/kg/day of Cp for 2 days, followed by 50 mg/kg/day for the next 3 days, and were sacrificed at 1 and 4 days after the last administration. The numbers of seminiferous epithelia were counted in the seminiferous tubules of stages II, V, VII and XII of the spermatogenic cycle. The data were expressed as numbers of spermatogenic cells per Sertoli cells per seminiferous tubule cross section. Animals in Group 1 showed decreased preleptotene spermatocytes at Day 7, decreased zygotene spermatocytes at Day 14, and decreased pachytene spermatocytes at Day 21. In group 2, testicular toxicity could also be clearly detected by this morphometric approach. The present morphometric study thus indicates that testicular toxicity can be detected from Day 7 even after a single administration of Cp.

Animals↗

PubMed1985

Morphometry of lower lumbar vertebrae as seen on CT scans: newly recognized characteristics.

Transaxial computed tomographic (CT) sections represent a new approach to vertebral morphometry, allowing certain measurements to be made in vivo for the first time. The cross-sectional morphology of the bodies and pedicles of L3, L4, and L5 was studied in a series of 213 vertebrae. This revealed that the pedicles of L5 arise more laterally from the body of L5 than from L3. Further, the lateral surfaces of the L5 body are inclined obliquely, unlike those of L3. L4 is transitional in form between L3 and L5, more closely resembling the former. This morphology explains the fact, hitherto unnoticed, that the lateral outlines of the pedicles and the lateral borders of the body of L5 are not normally imaged on plain anteroposterior radiographs. It is evident that pathologic changes of the lateral borders of the body of L5 may be invisible also. In cases of transitional vertebrae in the lumbosacral region the presence or absence of the lateral outlines of the pedicles and of the lateral borders of the vertebral body may be of help in identifying the vertebrae on conventional projections.

Adolescent↗

PubMed2001

The anterior iliac separation: alternative index for pelvic morphometry in fetuses with Down syndrome.

OBJECTIVE: The goal of this study was to assess the diagnostic use of an anterior iliac separation measurement as an alternative index for the iliac angle in the assessment of fetal pelvic morphometry. SUBJECTS AND METHODS: In 358 fetuses, the anterior iliac separation, iliac length, and iliac angle were prospectively measured on antenatal sonography. All measurements were obtained at two axial levels (superior and inferior). The gestational age of the fetus was recorded. The anterior iliac separation was normalized by iliac length, and coefficients of variation were calculated for all measurements. The effects of axial level and gestational age were assessed in a linear regression model. The diagnostic use of the anterior iliac separation relative to that of the iliac angle was assessed in a comparison of 24 fetuses with Down syndrome and 247 non-Down syndrome fetuses. RESULTS: The anterior iliac separation was less variable than the iliac angle at both superior and inferior levels. There were statistically significant effects for gestational age and axial level on both the anterior iliac separation and the iliac angle, but there was no significant effect for either factor when the anterior iliac separation was normalized by the iliac length. Comparing Down and non-Down syndrome fetuses, we found that the normalized anterior iliac separation had discriminating power similar to the iliac angle. CONCLUSION: The linear measurement of the anterior iliac separation has diagnostic properties similar to the iliac angle and is subject to less measurement variability. This simpler measurement may be particularly useful when normalized by the iliac length.

Down Syndrome↗

PubMed1988

Morphometry of Rambourg-positive and Rambourg-negative beta-cell granules after culture with low and high glucose concentrations.

Dispersed islet cells from noninbred ob/ob mice were cultured for 3 days with 3 or 20 mM D-glucose and silver stained according to Rambourg et al. Two tinctorial subsets of dark and light intracellular granules were analyzed by morphometry at the ultrastructural level. The two types of granules were similar in size and shape. However, with 3 mM glucose the dark granule cores were surrounded by larger vesicles than the light granules. With 20 mM glucose, both types of granule vesicles and cores became smaller and dark-granule cores became more rounded, compared with cultures with 3 mM glucose. The higher glucose concentration also induced a marked decrease in the number (-84%) and volume density (-90%) of dark granules. In contrast, the number of light granules increased (+60%) with maintenance of their volume density. We suggest that the dark Rambourg-positive and the light Rambourg-negative beta-cell granules are functionally distinct subsets. The dark granules are probably engaged in insulin discharge. We discuss the unclear role of the light granules with a view to previously postulated heterogeneities of the insulin granule pool and their significance for exocytosis and intracellular hormone degradation.

Animals↗

PubMed2006

Effects of type 1 diabetes on gray matter density as measured by voxel-based morphometry.

The effects of type 1 diabetes and key metabolic variables on brain structure are not well understood. Sensitive methods of assessing brain structure, such as voxel-based morphometry (VBM), have not previously been used to investigate central nervous system changes in a diabetic population. Using VBM, we compared type 1 diabetic patients aged 25-40 years with disease duration of 15-25 years and minimal diabetes complications with an age-matched, nondiabetic control group. We investigated whether lower than expected gray matter densities were present, and if so, whether they were associated with glycemic control and history of severe hypoglycemic events. In comparison with control subjects, diabetic patients showed lower density of gray matter in several brain regions. Moreover, in the patient group, higher HbA(1c) levels and severe hypoglycemic events were associated with lower density of gray matter in brain regions responsible for language processing and memory. Our study represents the first comprehensive study of gray matter density changes in type 1 diabetes and suggests that persistent hyperglycemia and acute severe hypoglycemia have an impact on brain structure.

Adolescent↗

PubMedDate not supplied

The prognostic significance of morphometry for squamous cell hyperplasia of the laryngeal epithelium.

Laryngeal biopsies of squamous cell hyperplasia with atypia were graded by means of morphometry, using five non-correlated nuclear parameters preselected with linear discriminant analysis, and were tested for their prognostic significance, in a follow-up study. Fifty-two biopsy specimens were obtained from 18 patients who were merely followed and if necessary underwent a repeated biopsy examination. The lesions of 10 patients progressed to invasive carcinoma. In 8 patients the second or further biopsies were again classified as squamous cell hyperplasia with atypia. For both groups the mean follow-up period was 7.2 years (range: 3 1/2-11). In the progressive group 73% of the biopsies were morphometrically classified as prognostically unfavourable, whereas the clinical outcome on the basis of the last biopsy was correctly predicted for 6 out of the 10 cases (mean probability: 94%), the other 4 cases were 'mis-classified', although for 3 cases with a low probability (mean: 60%). For a valuable morphometrical classification of lesions of individual patients, the results as presented are still insufficient. Morphometrical classification probabilities may be improved when the numbers of untreated patients with squamous cell hyperplasia with atypia do increase.

Adult↗