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This work intends to understand the spatial variation of channel morphological adjustment over 30 years (1987–2017). This region lacks an understanding of local variation in structural setup and its relative impact on channel morphological development as well as the direct control of channel hydrology in shaping the channel morphology. Besides measuring the reach-specific morphodynamics, this study is also engaged in understanding the impact of the allogenic processes (tectonics and gradient) and their local variations along with the response of autogenic processes and its reflection on channel morphological adjustment. Reach-specific channel morphodynamics is measured through training the observed dataset using the autoregressive integrated moving average model where the root mean squared error found at the best-fit model scenario was considered as the measure of relative variations in the morphometric variables. Channel reaches under direct structural control are morphologically most unstable where the faultline-induced possible sedimentation controls the fluvio-geomorphic processes intensively. The nature of morphological adjustment varies on different surface gradients but local variations in structural setup determine its spatial nature. The temporal variations of channel morphological parameters are responsive to peak discharge strength coupled with controls of channel gradient. Moreover, channel morphological change to hydrological variation is more sensitive on the piedmont surface compared to low gradient plain. This research contributes towards a close understanding of reach-specific channel morphological behaviour which is important while predicting its future and implementation of any river management strategies. [ABSTRACT FROM AUTHOR]

Hyperbaric oxygen therapy (HBOT) uses higher atmospheric pressure air or pure oxygen on the human body to facilitate wound healing. Usually, planimetry and oximetry are used in the quantitative evaluation of hyperbaric oxygen therapy effects. However, a noninvasive, quick and easy-to-perform method of evaluation is still required. Thus, the main aim of our study was to assess the usefulness of thermal imaging in evaluating the effects of hyperbaric oxygen therapy on hard-to-heal wounds and to compare these results with that of parameters obtained from planimetry. The studies were performed at the Burn Treatment Center in Siemianowice Slaskie. The study included 60 patients (28 women and 32 men) aged between 48 and 82 who had hard-to-heal wounds localized on their lower extremities. Thermal images were carried out during three stages (I: 0–10 sessions, II: 10–20 sessions and III: more than 20 sessions of HBOT) of the treatment cycle, before entering and after leaving the hyperbaric chamber, respectively. The results showed that the temperature of the regions of interest decreased with the number of completed treatments. Moreover, obtained isotherm area of crura as well as temperature differences between the regions of interest surrounding the wound decreased with the duration of treatment, which suggests an improvement in microcirculation through neovascularization. Our research may lead to planning of a new diagnostic device that uses and correlates several imaging techniques. It seems that the combination of thermal imaging with planimetry can give the physician an additional diagnosis information, as well as information about the effects of therapy at the structural and metabolic level. In addition, both methods are noninvasive, painless, fast and safe, which is very important in the treatment of hard-to-heal wounds. [ABSTRACT FROM AUTHOR]

The salivary glands and pancreas have comparable anatomic and antigenic properties and can share common pathogenetic mechanisms involving toxic or autoimmune processes. The aim of this study is to assess the correlation in size between the normal submandibular glands and the pancreas. The study was based on human autopsy specimens of the pancreas, neck and oral base from 22 adults, both sexes (mean age, 57.9 years). The pancreatic and submandibular ducts were injected with a contrast medium, and the area of the salivary and pancreatic glandular ductograms was measured with the aid of software for quantification of visual information. Samples of tissue from the salivary glands and the pancreas were studied by means of light microscopy. A high correlation was found between the planimetric size of the pancreas and the submandibular glands (correlation coefficient 0.497 and 0.699 for the right and the left gland, respectively). This ratio was close to 5:1. There were no significant differences in size for the left vs. right submandibular gland ( p = 0.39). The ductograms were significantly larger in size in males than in females ( p < 0.001). This study has proven a positive correlation in planimetric size between the normal submandibular glands and pancreas, a result that is expected to have possible clinical implications in the long-term follow-up of patients with chronic pancreatitis. [ABSTRACT FROM AUTHOR]

The dams are one of the important engineering structures used for water supply and different other important purposes. In order to provide safety, well-planned and implemented geodetic monitoring is very essential for such engineering structures, which constitute the aim of this study. In fact, micro-geodetic data can be exploited and used to survey the displacement of dam by measuring the horizontal and vertical coordinates at different dates from fixed positions (pillars) to other positions (targets). As a result, the superposition of the geodetic auscultation charts and the factors which can affect the stability of dams such as water level, hydrostatic pressure, and seismic state show a net correlation between these parameters and the auscultation variation at different periods. Geographical information system (GIS) techniques are used for mapping spatial variation of auscultation measures. These synthetic documents can help managers and decision makers in hydraulic management and water system protection. [ABSTRACT FROM AUTHOR]

Deep learning techniques are being rapidly applied to medical imaging tasks-from organ and lesion segmentation to tissue and tumor classification. These techniques are becoming the leading algorithmic approaches to solve inherently difficult image processing tasks. Currently, the most critical requirement for successful implementation lies in the need for relatively large datasets that can be used for training the deep learning networks. Based on our initial studies of MR imaging examinations of the kidneys of patients affected by polycystic kidney disease (PKD), we have generated a unique database of imaging data and corresponding reference standard segmentations of polycystic kidneys. In the study of PKD, segmentation of the kidneys is needed in order to measure total kidney volume (TKV). Automated methods to segment the kidneys and measure TKV are needed to increase measurement throughput and alleviate the inherent variability of human-derived measurements. We hypothesize that deep learning techniques can be leveraged to perform fast, accurate, reproducible, and fully automated segmentation of polycystic kidneys. Here, we describe a fully automated approach for segmenting PKD kidneys within MR images that simulates a multi-observer approach in order to create an accurate and robust method for the task of segmentation and computation of TKV for PKD patients. A total of 2000 cases were used for training and validation, and 400 cases were used for testing. The multi-observer ensemble method had mean ± SD percent volume difference of 0.68 ± 2.2% compared with the reference standard segmentations. The complete framework performs fully automated segmentation at a level comparable with interobserver variability and could be considered as a replacement for the task of segmentation of PKD kidneys by a human. [ABSTRACT FROM AUTHOR]

Introduction: Haematoma and oedema size determines outcome after intracerebral haemorrhage (ICH), with each added 10 % volume increasing mortality by 5 %. We assessed the reliability of semi-automated computed tomography planimetry using Analyze and Osirix softwares. Methods: We randomly selected 100 scans from 1329 ICH patients from two centres. We used Hounsfield Unit thresholds of 5-33 for oedema and 44-100 for ICH. Three raters segmented all scans using both softwares and 20 scans repeated for intra-rater reliability and segmentation timing. Volumes reported by Analyze and Osirix were compared to volume estimates calculated using the best practice method, taking effective individual slice thickness, i.e. voxel depth, into account. Results: There was excellent overall inter-rater, intra-rater and inter-software reliability, all intraclass correlation coefficients >0.918. Analyze and Osirix produced similar haematoma (mean difference: Analyze − Osirix = 1.5 ± 5.2 mL, 6 %, p ≤ 0.001) and oedema volumes (−0.6 ± 12.6 mL, −3 %, p = 0.377). Compared to a best practice approach to volume calculation, the automated haematoma volume output was 2.6 mL (−11 %) too small with Analyze and 4.0 mL (−18 %) too small with Osirix, whilst the oedema volumes were 2.5 mL (−12 %) and 5.5 mL (−25 %) too small, correspondingly. In scans with variable slice thickness, the volume underestimations were larger, −29%/−36 % for ICH and −29 %/−41 % for oedema. Mean segmentation times were 6:53 ± 4:02 min with Analyze and 9:06 ± 5:24 min with Osirix ( p < 0.001). Conclusion: Our results demonstrate that the method used to determine voxel depth can influence the final volume output markedly. Results of clinical and collaborative studies need to be considered in the context of these methodological differences. [ABSTRACT FROM AUTHOR]

Background: A variety of methods are used for estimating pituitary tumour size in clinical practice and in research. Quantitative methods, such as maximum tumour dimension, and qualitative methods, such as Hardy and Knosp grades, are well established but do not give an accurate assessment of the tumour volume. We therefore sought to compare existing measures of pituitary tumours with more quantitative methods of tumour volume estimation. Method: Magnetic resonance imaging was reviewed for 99 consecutive patients with pituitary adenomas awaiting surgery between 2010 and 2013. Maximal tumour diameter, Hardy and Knosp grades were compared with tumour volume estimates by the ellipsoid equation, [ $$ \frac{4}{3}\pi\ (a.b.c) $$], (i.e. ellipsoid volume) and slice-by-slice perimetry (i.e. perimeter volume). Results: Ellipsoid and perimeter methods of tumour volume estimation strongly correlated ( R = 0.99, p < 0.0001). However the correlation was less strong with increasing tumour size, with the ellipsoid method slightly underestimating. The mean differences were −0.11 (95 % CI, −0.35, 0.14), −0.74 (95 % CI, −2.2, 0.74) and −1.4 (95 % CI, −6.4, 3.7) for micro-tumours, macro-tumours and giant tumours respectively. Tumour volume correlated with maximal diameter, following a cubic distribution. Correlations of tumour volume with Hardy and Knosp grades was less strong. Conclusions: Perimeter and ellipsoid methods give a good estimation of tumour volume, whereas Knosp and Hardy grades may offer other clinically relevant information, such as cavernous sinus invasion or chiasmal compression. Thus the different methods of estimating tumour size are likely to have different clinical utilities. [ABSTRACT FROM AUTHOR]

Objectives: To deploy and evaluate a stereological point-counting technique on abdominal CT for the estimation of visceral (VAF) and subcutaneous abdominal fat (SAF) volumes.Methods: Stereological volume estimations based on point counting and systematic sampling were performed on images from 14 consecutive patients who had undergone abdominal CT. For the optimization of the method, five sampling intensities in combination with 100 and 200 points were tested. The optimum stereological measurements were compared with VAF and SAF volumes derived by the standard technique of manual planimetry on the same scans.Results: Optimization analysis showed that the selection of 200 points along with the sampling intensity 1/8 provided efficient volume estimations in less than 4 min for VAF and SAF together. The optimized stereology showed strong correlation with planimetry (VAF: r = 0.98; SAF: r = 0.98). No statistical differences were found between the two methods (VAF: P = 0.81; SAF: P = 0.83). The 95% limits of agreement were also acceptable (VAF: -16.5%, 16.1%; SAF: -10.8%, 10.7%) and the repeatability of stereology was good (VAF: CV = 4.5%, SAF: CV = 3.2%).Conclusions: Stereology may be successfully applied to CT images for the efficient estimation of abdominal fat volume and may constitute a good alternative to the conventional planimetric technique.Key Points: Abdominal obesity is associated with increased risk of disease and mortality. Stereology may quantify visceral and subcutaneous abdominal fat accurately and consistently. The application of stereology to estimating abdominal volume fat reduces processing time. Stereology is an efficient alternative method for estimating abdominal fat volume. [ABSTRACT FROM AUTHOR]

Stereology is a volume estimation method, typically applied to diagnostic imaging examinations in population studies where planimetry is too time-consuming (Chapman et al. Kidney Int 64:1035-1045, ), to obtain quantitative measurements (Nyengaard J Am Soc Nephrol 10:1100-1123, , Michel and Cruz-Orive J Microsc 150:117-136, ) of certain structures or organs. However, true segmentation is required in order to perform advanced analysis of the tissues. This paper describes a novel method for segmentation of region(s) of interest using stereology data as prior information. The result is an efficient segmentation method for structures that cannot be easily segmented using other methods. [ABSTRACT FROM AUTHOR]

Vena contracta width (VCW) and effective regurgitant orifice area (EROA) are well established methods for evaluating mitral regurgitation using transesophageal echocardiography (TEE). For color-flow Doppler (CF) measurements Nyquist limit of 50-60 cm/s is recommended. Aim of the study was to investigate the effectiveness of a baseline shift of the Nyquist limit for these measurements. After a comprehensive 2-dimensional (2D) TEE examination, the mitral regurgitation jet was acquired with a Nyquist limit of 50 cm/s (NL50) along with a baseline shift to 37.5 cm/s (NL37.5) using CF. Moreover a real time 3-dimensional (RT 3D) color complete volume dataset was stored with a Nyquist limit of 50 cm/s (NL50) and 37.5 cm/s (NL37.5). Vena contracta width (VCW) as well as Proximal Isovelocity Surface Area (PISA) derived EROA were measured based on 2D TEE and compared to RT 3D echo measurements for vena contracta area (VCA) using planimetry method. Correlation between VCA 3D NL50 and VCW NL50 was 0.29 ( p < 0.05) compared to 0.6 ( p < 0.05) using NL37.5. Correlation between VCA 3D NL50 and EROA 2D NL50 was 0.46 ( p < 0.05) vs. 0.6 ( p < 0.05) EROA 2D NL37.5. Correlation between VCA 3D NL37.5 and VCW NL50 was 0.45 ( p < 0.05) compared to 0.65 ( p < 0.05) using VCW NL37.5. Correlation between VCA 3D NL37.5 and EROA 2D NL50 was 0.41 ( p < 0.05) vs. 0.53 ( p < 0.05) using EROA 2D NL37.5. Baseline shift of the NL to 37.5 cm/s improves the correlation for VCW and EROA when compared to RT 3D NL50 planimetry of the vena contracta area. Baseline shift in RT 3D to a NL of 37.5 cm/s shows similar results like NL50. [ABSTRACT FROM AUTHOR]

Stereological techniques using point counting and planimetry have been used to estimate pituitary gland volume. However, many studies have estimated pituitary gland volume by the mathematical approach the elliptic formula. The objective of the current study was to determine pituitary gland volume using stereological methods and elliptic formula on magnetic resonance imaging (MRI). In this study, pituitary gland volumes were estimated in a total of 28 subjects (22 females, 6 males,) who were free of any pituitary or neurological symptoms and signs. The mean ± SD pituitary gland volumes for the point counting, planimetry and elliptic formulae groups were 582.14 ± 140.16 mm, 610.08 ± 133.17 mm, and 432.82 ± 147.38 mm, respectively. The mean CE for the pituitary gland volume estimates derived from the point counting technique was 8.07%. No significant difference was found between point counting and planimetric methods for the pituitary gland volume ( P > 0.05). In addition, there was a 26.14 and 29.71% underestimation of pituitary volume as measured by the elliptic formula compared to the point counting and planimetric techniques, respectively. From these results, it can be concluded that stereological techniques are unbiased, efficient and reliable methods and are ideally suitable for in vivo examination of MRI data for pituitary gland volume estimation. Hence, we suggest that estimating pituitary gland volume using MRI study and stereology may be clinically relevant for pituitary surgeons for the investigation of the structure and function of the pituitary gland. [ABSTRACT FROM AUTHOR]

The size of brain ventricles is especially relevant in some brain diseases such as epilepsy, schizophrenia and other neurodegenerative diseases. Many studies have been conducted to assess the brain ventricles. To the best of our knowledge, however, there is no fourth, third and lateral ventricles volume study evaluating the efficiency and accuracy of point-counting and planimetry methods of the Cavalieri principle in the literature. In the current study, we estimated the volume of intracerebral ventricles in normal subjects using stereological methods. The volumes of fourth, third and lateral ventricle were estimated in 14 young Turkish volunteers (7 males and 7 females), aged between 18 and 36 years and free of any neurological symptoms and signs, using serial magnetic resonance imaging (MRI). Volumes of intracerebral ventricles were determined on MRIs using the point-counting and planimetry methods. The mean results of the point-counting method were 14.7 ± 4.2, 8.7 ± 3.0 and 131.8 ± 33.1 mm for the fourth, third and lateral ventricles, respectively. The mean results of the planimetry method were 15.4 ± 3.4, 8.6 ± 3.5 and 153.7 ± 34.6 mm for the fourth, third and lateral ventricles, respectively. Ventricle volumes obtained by the two different methods were not statistically different ( p > 0.05) and they correlated well with each other. Good agreement was found between results obtained with the point-counting and planimetry techniques. The findings of the present study using stereological methods could provide data for the evaluation of normal and pathological volumes of intracerebral ventricles. [ABSTRACT FROM AUTHOR]

The cerebellum is involved in motor learning and cognitive function in human. Many studies have been conducted to assess the cerebellar volume. To the best of our knowledge, there is no cerebellar volume study evaluating the efficiency and the accuracy of point-counting and planimetry methods of the Cavalieri principle in the literature. In this study, the volume of cerebellum was estimated in 53 Turkish young volunteers (26 males and 27 females), aged between 20 and 25 who are free of any neurological symptoms and signs, using serial magnetic resonance (MR) images. The cerebellar volumes of subjects were determined on MR images using the point-counting and planimetry methods. The mean results of planimetry method were 116.69 ± 10.1 and 114.41 ± 9.3 cm3 in males and females, respectively. The mean results of point-counting method were 116.34 ± 10.6 and 113.48 ± 8.8 cm3 in males and females, respectively. Our results revealed that female subjects had less cerebellar volumes compared with males, although there was no statistical significant difference between genders ( P > 0.05). Total cerebellar volumes obtained by two different methods were not statistically different ( P = 0.189) and they were correlated well to each other ( r = 0.935). We found that the point-counting method takes less time than the planimetric method (mean 8 ± 3.6 vs. 15 ± 5.5 min). Thus, while planimetric and stereological approaches yield very similar results, the stereological method has the advantage of greater speed and, therefore, efficiency. [ABSTRACT FROM AUTHOR]

Several methods have been described to evaluate the degree of lumbar lordosis. However, suggested methods have used non-standardized terminology and landmarks to measure the degree of lumbar lordosis. In the present study a practical method for evaluating the degree of lumbar lordosis is described and, for this purpose, 24 lateral roentgenograms were obtained retrospectively from the archive of Department of Physical Medicine and Rehabilitation, Ondokuz Mayis University, Samsun, Turkey. The length between the superior and inferior angles of the first and fifth lumbar vertebral bodies, and the area behind the lumbar vertebral bodies, were estimated using the point counting and planimetry methods. A new unit, the projection area per length squared (PAL) was described on lateral roentgenograms. The planimetric approach was used as the gold standard in the present study. The point-counting method was also used to estimate the PAL and it was repeated three times to determine the variability of the technique. To evaluate the estimates’ accuracy, the results of point-counting were compared with those of the planimetry methods. The PAL changed by between 3.93 and 13.59% for the examined subjects. A high correlation was also noted between the results of the point-counting and planimetry methods ( r = 0.997). It is concluded that the PAL approach could provide accurate and reproducible data for evaluating the degree of lumbar lordosis and low back pain. [ABSTRACT FROM AUTHOR]

We compared two different magnetic resonance (MR) sequences [steady-state free precession (SSFP) and gradient echo fast low-angle shot (FLASH)] for the assessment of aortic valve areas in aortic stenosis using transesophageal echocardiography (TEE) as the standard of reference. Thirty-two patients with known aortic stenosis underwent MR (1.5 T) using a cine SSFP sequence and a cine FLASH sequence. Planimetry was performed in cross-sectional images and compared to the results of the TEE. In seven patients the grade of stenosis was additionally assessed by invasive cardiac catheterization (ICC). The mean aortic valve area measured by TEE was 0.97+/-0.19 mm(2), 1.00+/-0.25 mm(2) for SSFP and 1.25+/-0.23 mm(2) based on FLASH images. The mean difference between the valve areas assessed based on SSFP and TEE images was 0.15+/-0.13 cm(2) (FLASH vs TEE: 0.29+/-0.17 cm(2)). Bland-Altman analysis demonstrated that measurements using FLASH images overestimated the aortic valve area compared to TEE. Comparing ICC with MRI and TEE, only a weak to moderate correlation was found (ICC vs TEE: R=0.52, p=0.22; ICC vs SSFP: R=0.20, p=0.65; ICC vs FLASH: R=0.16, p=0.70). Measurements of the aortic valve area based on SSFP images correlate better with TEE compared to FLASH images. [ABSTRACT FROM AUTHOR]

The prognostic significance of the size of mastoid air cell system in the results of myringoplasty has been a matter of debate. Fifty ears with dry central perforation following C.S.O.M. were investigated. The size of mastoid air cell system was determined with planimetry of the X-ray picture and eustachian tube function was assessed using flourescein dye and nasal endoscopy. Myringoplasty was performed in all the 50 ears and postoperative results in terms of graft take up and hearing gain were assessed. The correlation between the size of mastoid air cell system, results of myringoplasty and tubal function has been discussed. The results show no correlation between the size of mastoid air cell system, postoperative results of myringoplasty and eustachian tube function. [ABSTRACT FROM AUTHOR]

We compared two methods of estimating the volume of 10 formalin-fixed brains using MRI. MRI was performed and total brain volume was then assessed using two distinct techniques: a stereological point-counting technique based on the Cavalieri principle, and an edge-tracing technique. The total brain volumes obtained using these two techniques were similar and correlated closely with each other ( r = 0.97). Both methods could be optimised to a similar degree while maintaining the coefficient of error at an acceptably low level. However, the stereological assessment of brain volume required between 20 min and 30 min per brain, depending on the number of points per sampling grid, compared with 1 h per brain using the planimetric method. Thus, while planimetric and stereological approaches yield very similar results, the stereological method has the advantage of greater speed and, therefore, efficiency. [ABSTRACT FROM AUTHOR]

The environment versus the genetic influence on the size of the mastoid pneumatization has been debated for years. A concrete evidence of the influence of environmental factors (e.g. inflammation) or heredity on pneumatization is still lacking. In this study the extent to mastoid peumatization in thirty otosclerotic ears was compared with control ears. The size of mastoid pneumatization was measured by the use of Law lateral x-ray projection with the help of planimetry. It was found that the average pneumatized area in otosclerotic ears was 14.73+ -3.55 cm2 compared to 10.60+3.62 cm2 in control ears which was statistically significant. In addition the mean area of mastoid air system was found to be more in the operated ears compared to the contralateral ears, the difference being statistically significant. However there was no correlation of mastoid pneumatization with degree and duration of hearing loss and type of otosclerotic focus. Our findings therefore show a link between otosclerosis and highly pneumatized mastoids thus indicating a likelihood of heredity playing a role in determining final type ot pneumatization. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Dermatological Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Dermatological Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The planimetric, flow cytometric, and immunohistochemical characteristics of the macrofollicular variant of papillary thyroid carcinoma (MFVPTC) have not been reported before. The clinical, morphological, immunohistochemical, planimetric, and flow cytometric characteristics of six cases of the MFVPTC and six of the follicular variant of papillary thyroid carcinoma (FVPTC) were analyzed. Patients had undergone surgical treatment. The mean age was 38 (range 29-64 yr), and five were women. Tumors had a mean size of 3.2 cm (range 0.3-4.5 cm). Half were originally diagnosed as goiter. Macrofollicles had a mean diameter of 345.5 μm, perimeter of 1237 μm, and area of 13,779 μm, with nuclear changes of PTC. Mean follow-up was 107 mo (range 12-277), and neither lymph node metastases nor recurrence were seen. Differences in diameter, perimeter, and area between the macrofollicular and follicular variants were found. Follicular neoplastic cells were thyroglobulin and S-100 protein positive in macrofollicles and normofollicles. All were negative to cytokeratin and to high-mol-wt keratin. All tumors were diploid. There were no significant differences in follow-up, DNA content, nor immunohistochemical reactivity. Differences in diameter ( p<0.00006), perimeter ( p<0.0001), and area ( p<0.001) were observed. It is important to recognize this variant because it could be misdiagnosed as benign thyroidal lesions. [ABSTRACT FROM AUTHOR]

A planimetric study of megakaryopoiesis in various chronic myeloproliferative diseases (CMPD) was performed and the results compared with those from controls and myelitis of rheumatic origin. Morphometric measurements included at least 200 megakaryocytes in each case observed in Giemsa-stained semithin sections of resin-embedded core biopsies. Twenty specimens were evaluated from the controls and inflammatory disorders and from each of the following CMPD: 1, chronic granulocytic leukaemia (CGL); 2, polycythaemia vera (P. vera); 3, chronic megakaryocytic-granulocytic myelosis without or with minimal increase in reticulin fibre content (CMGM); 4, myelofibrosis or osteomyelosclerosis (MF/OMS). Megakaryocytes were classified as follows: 1, normal megakaryocytes at all stages of maturation; 2, giant forms; 3, microforms; 4, intussusceptions; 5, a-nuclear cytoplasmic fragments; 6, naked nuclei or necrotic forms. The results of this study demonstrate obvious abnormalities of megakaryopoiesis in addition to the increase in absolute numbers of megakaryocytes per marrow area and their different sizes as reported earlier (Thiele et al. 1982). Aberrations are particularly conspicuous when pure granulocytic proliferation or neoplasia of CGL is compared with the so-called mixed cellularity of megakaryocytes and granulocytes in CMGM including MF/OMS. Abnormalities of the giant forms of megakaryocytes are especially evident and comprise irregular cellular and nuclear perimeters (as calculated by a modified shape factor) in the two latter entities (CMGM-MF/OMS). This remarkable feature is associated with a disorganization of nuclear development and/or a disproportionate nuclear-cytoplasmic ratio which has never been observed in CGL previously. In combination with this striking cellular anomaly, which is compatible with an extreme amoeboid shape of giant forms in CMGM and MF, intussuceptions and a-nuclear cytoplasmic fragments are frequently encountered. The final stage of megakaryopoiesis, i.e. naked nuclei, are increased in number in all CMPD, probably because of enhanced proliferation and platelet shedding. Naked nuclei are often small in CGL (as remnants of the frequent micromegakaryocytes) and large in P. vera and CMGM/MF (depending on the high incidence of giant megakaryocytes in these latter disorders). [ABSTRACT FROM AUTHOR]

By use of cryofracture and scanning electron microscopy of human amniochorion we have captured images of all the major layers of the tissue. Correlation of confocal and electron-microscope data has allowed greater understanding of how these cellular and acellular layers interconnect in order to maintain their integrity as a multilaminar tissue. This is not straightforward as mutual sliding or area change is required of concentric curved surfaces which expand and contract as does the amnion. In this paper we suggest a mechanism by which the amnion is able to slide with respect to the chorion and still maintain continuity as a structural unit. It is based on the observation of complementary gyri and sulci on surfaces facing the spongy layer which is a shear plane. Cellular detail at higher resolution of the amniotic epithelium and acellular layers provides a more complete description of structural composition than was previously available. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging is increasingly used in stroke trials for early diagnosis and follow-up of lesion size. Since volumetric measurement remains a laborious and time-consuming task, a rapid and reliable method for the assessment of lesion size has been developed and validated in diffusion weighted imaging (DWI) and fluid attenuated inversion recovery (FLAIR) sequences. These were serially obtained in 40 patients less than 8 h after the onset of symptoms of a middle cerebral artery territory stroke (day 1), as well as on days 3 and 18. For each of 16 (DWI) or 20 (FLAIR) transverse sections obtained on each occasion, lesion size was estimated as a percentage of the total hemisphere. Percentage values from all sections were summed up and expressed as arbitrary units. Results obtained using this approximate planimetric method (APM) were compared with those from a standard volumetric approach. Lesion volumes as determined by both methods were highly correlated (DWI: r=0.966, FLAIR: r=0.979, p<0.001). To conclude, the APM is simple, rapid and reliable for the estimation of lesion size in acute ischemic stroke. It can be recommended for broader application in clinical trials. [ABSTRACT FROM AUTHOR]