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The correlation of cognitive decline with frontotemporal dementia induced annualized gray matter loss using diffeomorphic morphometry.

This study uses large deformation medical image registration to analyze, in a disease-specific normalized space, the annual rate of gray matter atrophy caused by frontotemporal dementia (FTD) and its correlation with cognitive decline. The analysis consists of three parts. First, a labeled structural MRI atlas is deformed into the shape of an average FTD brain. Second, annualized FTD-related atrophy of gray matter structures is estimated for each patient in the database. Third, the group-wise annualized atrophy rate caused by FTD is correlated, for each gray matter voxel, with declining performance on cognitive tests. This study gives insight into the relationship between FTD-related progressive cortical atrophy and loss in cognitive function.

Aged↗

Brain morphometry using diffusion-weighted magnetic resonance imaging: application to schizophrenia.

Loss of cortical gray matter is accompanied by a commensurate increase in the sulcal and intraventricular cerebrospinal fluid volume. On diffusion-weighted magnetic resonance imaging, this would be reflected as a higher apparent diffusion coefficient in affected brain regions. On the basis of the above premise, we suggest that the apparent diffusion coefficient may be used as a surrogate marker for the assessment of regional brain volume deficits. We demonstrate this approach by voxelwise analysis of registered apparent diffusion coefficient images from a group of 15 patients with schizophrenia and 15 age-matched healthy controls. We found widespread regional apparent diffusion coefficient increases in patients. Affected areas included the bilateral insular cortex, hippocampus, temporal lobe, and occipital areas. These results largely concur with previous findings of cortical volume deficits in schizophrenia.

Adult↗

Pathology and morphometry of the paraspinous muscles in nonidiopathic scoliosis.

The muscle fibers in 19 patients with nonidiopathic scoliosis were generally small, especially on the concave side of the curve. Type 1 fibers were more frequently atrophic than type 2 fibers, but the former usually remained larger than the latter. Type 1 preponderance was greater on the convex side of the curve; type 2A preponderance occurred bilaterally. These changes are similar to those of idiopathic scoliosis. They resemble those of endurance training or stretch and are interpreted as secondary to the curve.

Adolescent↗

A Bayesian morphometry algorithm.

Most methods for structure-function analysis of the brain in medical images are usually based on voxel-wise statistical tests performed on registered magnetic resonance (MR) images across subjects. A major drawback of such methods is the inability to accurately locate regions that manifest nonlinear associations with clinical variables. In this paper, we propose Bayesian morphological analysis methods, based on a Bayesian-network representation, for the analysis of MR brain images. First, we describe how Bayesian networks (BNs) can represent probabilistic associations among voxels and clinical (function) variables. Second, we present a model-selection framework, which generates a BN that captures structure-function relationships from MR brain images and function variables. We demonstrate our methods in the context of determining associations between regional brain atrophy (as demonstrated on MR images of the brain), and functional deficits. We employ two data sets for this evaluation: the first contains MR images of 11 subjects, where associations between regional atrophy and a functional deficit are almost linear; the second data set contains MR images of the ventricles of 84 subjects, where the structure-function association is nonlinear. Our methods successfully identify voxel-wise morphological changes that are associated with functional deficits in both data sets, whereas standard statistical analysis (i.e., t-test and paired t-test) fails in the nonlinear-association case.

Aged↗

Ultrastructural morphometry of normal human dermal-epidermal junction. The influence of age, sex, and body region on laminar and nonlaminar components.

To obtain baseline data for future studies on such processes as wound healing, carcinogenesis, and blistering, a morphometric analysis of the dermal-epidermal junction was undertaken on normal skin from 3 or 4 standard sites on the arm and leg of 12 subjects aged 20-60 years. Lamina densa was thinner in females than in males (p less than 0.01) but no sex difference was apparent for lamina lucida. Both laminar elements were thinner beneath melanocytes than beneath keratinocytes. Sex, age, and body region had no apparent influence on numbers of hemidesmosomes or basal cell plasmalemmal vesicles, nor was there a significant variation of these structures among individuals. Numbers of dermal microfibril bundles diminished with age (p less than 0.01). Anchoring fibril counts varied widely both among individuals (p less than 0.025) and within the same subject; there were fewer in the upper arm compared with different parts of the leg (p less than 0.005). These results emphasize the importance of appropriate controls in studies of physiologic and pathologic conditions involving the dermal-epidermal junction.

Adult↗

Quantitative evaluation of severity in psoriatic lesions using three-dimensional morphometry.

The severity of psoriasis has been traditionally assessed by measures, such as the psoriasis area and severity index (PASI), the psoriasis severity scores, and the lesional severity scores. As a result, even experienced dermatologists show variations when attempting to determine the severity of psoriasis. Therefore, a better non-invasive and objective measurement of clinical signs is needed. In this study, an instrument, a so-called 'stereoimage optical topometer' (SOT), based on a new concept of 'stereoimaging' was used to measure the three-dimensional skin surface. The aim of this study was to compare the results obtained by the SOT with the visual score of psoriasis lesion. Thirty psoriatic patients were enrolled in this study. Initially, the severity of the infiltration and the scale of 134 psoriatic lesions were assessed by using a visual scoring system (0: none, 1: mild, 2: moderate, 3: severe, and 4: very severe), as scored by five dermatologists. The SOT was then used to quantify the severity of each psoriatic lesion using four three-dimensional SOT parameters (Sa, SL, SA, and SV). Secondly, the involved skin-surface area in the psoriasis cases was scored by the naked eye by the five dermatologists and by image analysis. Statistically significant differences were observed between grades 0, 1, 2, and 3 in terms of the severity measurements of the individual psoriatic lesions by SOT when using the parameters Sa, SL, SA, and SV. Therefore, it was concluded that there is a strong correlation between the results measured by visual scoring and by SOT in psoriasis.

Adult↗

Long-term synaptic morphometry changes after induction of long-term potentiation and long-term depression in the dentate gyrus of awake rats are not simply mirror phenomena.

Mechanisms of expression of long-term synaptic plasticity are believed to involve morphological changes of the activated synapses and remodelling of connectivity. Here, we investigated changes in synaptic and neuronal parameters in the dentate gyrus 24 h after induction of long-term potentiation (LTP) and long-term depression (LTD) in awake rats. In dentate granule cells, tetanization of the medial or lateral perforant paths induces LTP in specific synaptic bands along the dendrites in the middle and outer molecular layers, respectively, and tetanization of the lateral path induces robust LTD heterosynaptically in the middle molecular layer. This functional segregation allowed us to assess morphological changes associated with LTP and LTD in each pathway in the same population of neurons. Electron microscopy and unbiased counting methods were used to estimate neuronal density, axospinous, axodendritic and perforated synapse density, multiple synapse bouton density and postsynaptic density (PSD) area. Whereas there was no change in neuronal density, PSD area and multiple synapse boutons 24 h after either LTP or LTD, there was a noninput-specific increase in unperforated axospinous synapses after both LTP and LTD. However, we found that LTP of the medial, but not lateral, perforant path is associated with a specific increase in perforated axospinous synapses in the potentiated area. We also show that heterosynaptic LTD is associated with an input-specific increase in axodendritic synapse density. These results suggest that each perforant pathway may differ with respect to the nature of LTP-induced long-term changes and show that morphologically LTD is not simply the converse of LTP.

Animals↗

Effect of long-term vitamin D2 treatment on bone morphometry and biochemical values in anticonvulsant osteomalacia.

Quantitative morphometric analyses of iliac crest biopsies from 20 epileptic patients receiving chronic anticonvulsant therapy have been performed before and after 4-8 months of vitamin D2 treatment with 9 000 U per day. Biochemical quantities, including serum 25-hydroxycholecalciferol (25-HCC) and serum parathyroid hormone (iPTH), were measured. The anticonvulsant osteomalacia found in the initial bone biopsies was characterized by an increased amount of ummineralized bone, an increased bone resorption and, contrary to vitamin D deficiency, an increased bone mineralization and bone formation. Bone resorption and bone formation were probably equally increased since the amount of cancellous bone was normal. Except for a slight increase in osteoidcovered surfaces and osteoclastic resorption surfaces, the bone changes were normalized after vitamin D2 treatment, leading to a mean serum level of 25-HCC 2.4 times above normal. Serum iPTH was normal before and unchanged during D2 therapy. The urinary calcium excretion remained decreased. The investigation characterizes anticonvulsant osteomalacia as a specific bone disease different from that of vitamin D deects of vitamin D metabolites on receptor cells.

Adult↗

Aseptic necrosis of bone following renal transplantation. Clinical and biochemical aspects and bone morphometry.

Aseptic necrosis of bone has developed 5--48 months (mean 23) after renal transplantation in 22 (11%) of 195 patients with graft function for more than 6 months. The bone lesions were mainly localized to weight-bearing cancellous bone areas, most often the femoral heads. The mean duration of hemodialysis was significantly longer in recipients with aspetic necrosis than in those without. The serum concentration of phosphate was reduced and the serum concentration of parathyroid hormone increased in both groups of recipients. Quantitative histological examination of iliac crest biopsies showed a pronounced reduction of spongy bone (osteopenia) in recipients with aseptic necrosis compared with both normals and recipients without aseptic necrosis. Both patient groups showed similar changes in bone remodelling, indicating decreased bone formation. These findings suggest that osteopenia is an important contributory factor in the development of aseptic necrosis of bone after transplantation. The osteopenia may be a consequence of both the uremic bone disease before transplantation and the immunosuppressive treatment after transplantation.

Adolescent↗

Quantitation of gastric intestinal metaplasia by morphometry in Japanese patients.

With the aid of an image processor, the length of the intestinal metaplasia (IM) was recorded in 33 gastrectomy specimens (23 with early gastric cancer and 10 with gastric peptic ulcer). A total of 1917 sections were analyzed. The length of the areas with IM and the total length of the muscularis mucosa were measured in individual sections. The resulting ratio (length of IM/length of muscularis mucosa) was noted as the intestinal metaplasia index (IMI), as an expression of the extension of IM in the specimens. The IMI was influenced by the age of the patient and by the histologic type of the tumor: a higher IMI was found among older patients and among patients with adenocarcinoma of intestinal type. A comparison with a similar study done in gastrectomy specimens from Swedish patients indicates that despite the latter group being older, and the tumors being more advanced, the IM was much more extended in the gastric mucosa of the Japanese patients with gastric adenocarcinomas of intestinal type. From the results it is suggested that extended IM in the gastric mucosa may have some bearing on the histogenesis of gastric carcinomas, particularly adenocarcinomas of intestinal type.

Adenocarcinoma↗

Acute and subacute effects of thiamine deficiency on the morphometry and cell kinetics of jejunal and ileal epithelial cells.

The effects of acute and subacute thiamine deficiency on jejunal and ileal epithelial cells were studied in rats, using crypt and villus cell population, crypt cell production per crypt (CCPC), crypt growth fraction (Ip) and crypt cell cycle time (Tc) as parameters. In acute thiamine deficiency there was marked jejunal hypoplasia of the crypt and villus, but in the ileum there was hypoplasia only of the crypt. The jejunal epithelium of the subacute thiamine deficiency (STD) group showed no morphometric changes. In contrast, in the ileal epithelium of STD rats there was decreased crypt depth and villus cell population. Thiamine deficiency had no significant effect on CCPC, Ip and Tc.

Animals↗

Glomerular morphometry II: familial and nonfamilial haematuria.

Differential glomerular cell counts and measurements of glomerular diameter were made in 13 children with Alport's syndrome (AS), four with benign familial haematuria (BFH) and 15 with nonfamilial haematuria (NFH). Mesangial cellularity was increased in the six cases of NFH with diffuse mesangial deposits of IgA (IgA +). In AS, IgA + and -NFH, epithelial cellularity decreased with age while glomerular diameter increased. In AS mesangial and endothelial cellularity also decreased with age. These findings support the view that AS, IgA + and -NFH are three distinct entities. BFH, although similar in several respects to IgA -NFH, should nevertheless be retained as a separate category by virtue of its familial incidence of haematuria.

Adolescent↗

Classification of normal colorectal mucosa and adenocarcinoma by morphometry.

Semi-automatic image analysis was used to make a morphometrical assessment of 15 nuclear and cellular variables in normal (n = 20) and malignant (n = 30) colorectal epithelium. Principal components analysis on the matrix of correlations between variables identified four main sources of variation within the dataset. These were, in decreasing order of importance: (1) nuclear size, nuclear cytoplasmic ratio and nuclear position within the cell; (2) the variability of nuclear size; (3) nuclear elongation and polarity; (4) nuclear shape and its variation. Discriminant analysis was conducted between histologically normal mucosa (n = 10) and adenocarcinoma in ulcerative colitis (n = 20). Using stepwise variable selection, the mean nuclear cytoplasmic ratio (normal, mean 20.4 (s.d. +/- 2.0); tumour, mean 39.7 (s.d. +/- 7.0)) and the coefficient of variation of nucleus to cell apex distance (normal, mean 19.2 (s.d. +/- 7.5); tumour, mean 47.8 (s.d. +/- 9.1)) were chosen as discriminating features. They were used to derive a discriminant function which gave perfect discrimination between the two groups. Scatter plots of these two variables confirmed complete separation of normal mucosa from adenocarcinoma and provided a simple method of applying the discriminant function. Discriminatory performance did not deteriorate when the function was applied to further normals (n = 10) and adenocarcinoma (n = 10). This study highlights the descriptive differences between normal and malignant colorectal epithelium and shows that case allocation may be made to these two lesion categories using a morphometrically-derived classification rule.

Adenocarcinoma↗

Assessment of oesophagitis by histology and morphometry.

Morphometric measurements of nuclear area, nuclear concentration and nucleolar dimensions in defined tissue zones of orientated oesophageal biopsy sections were compared between three patient groups--asymptomatic/normal endoscopy (n = 8); symptomatic reflux/normal endoscopy (n = 17); and symptomatic/endoscopic oesophagitis (n = 15). No significant differences could be shown for any mean parameter between clinical groups. In a further group of 16 patients, identical morphometric measurements were made in non-orientated grasp biopsies and correlated with prolonged ambulatory pH data. No significant correlations could be shown between nuclear parameters and acid reflux measurements. These results suggest that morphometric measurement cannot be recommended as a diagnostic tool in the diagnosis of oesophagitis, although it may be useful in the assessment of individual therapeutic response in clinical trials.

Adult↗