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Acquiring image data of bone biopsies by a micro-CT scanner is today a common technique. The amount of data to be assessed is huge. The task to assess quantitative measures requires a concise visualization. We present visualization techniques that can be used interactively on state-of-the-art PCs and demonstrate how the frontier can be pushed further. A skeletonization process is applied to the image of the bone to create the central surface. After triangulation this surface can be renderd at interactive frame rates. When the surface is additionally colored by local measures (mean grey value of image data, local thickness) the overall structure and details can be recognized at the same time. This can facilitate the exploration of the biopsy and can help finding special features.

Vertebral fracture is one of the major adverse clinical consequences of osteoporosis; however, there are few data concerning the incidence of vertebral fracture in population samples of men and women. The aim of this study was to determine the incidence of vertebral fracture in European men and women. A total of 14,011 men and women aged 50 years and over were recruited from population-based registers in 29 European centers and had an interviewer-administered questionnaire and lateral spinal radiographs performed. The response rate for participation in the study was approximately 50%. Repeat spinal radiographs were performed a mean of 3.8 years following the baseline film. All films were evaluated morphometrically. The definition of a morphometric fracture was a vertebra in which there was evidence of a 20% (+4 mm) or more reduction in anterior, middle, or posterior vertebral height between films--plus the additional requirement that a vertebra satisfy criteria for a prevalent deformity (using the McCloskey-Kanis method) in the follow-up film. There were 3174 men, mean age 63.1 years, and 3,614 women, mean age 62.2 years, with paired duplicate spinal radiographs (48% of those originally recruited to the baseline survey). The age standardized incidence of morphometric fracture was 10.7/1,000 person years (pyr) in women and 5.7/1,000 pyr in men. The age-standardized incidence of vertebral fracture as assessed qualitatively by the radiologist was broadly similar-12.1/1,000 pyr and 6.8/1,000 pyr, respectively. The incidence increased markedly with age in both men and women. There was some evidence of geographic variation in fracture occurrence; rates were higher in Sweden than elsewhere in Europe. This is the first large population-based study to ascertain the incidence of vertebral fracture in men and women over 50 years of age across Europe. The data confirm the frequent occurrence of the disorder in men as well as in women and the rise in incidence with age.

Osteoporosis is mainly diagnosed by means of bone densitometry. Dual X-ray absorptiometry examinations represent the basis for a highly reproducible and correct measurement. At present, densitometry is the only method at our disposal capable of assessing material-related fracture risk. The calculation of general fracture risk is dependent on a number of varios factors and is, therefore, not to be deduced from bone density values only. Reference values are necessary in order to estimate bone strength. The most sensible way to achieve this is to compare measured values with a normal, healthy population (T score). Material-related fracture risk increases with the decrease of bone density.

The problem of quantifying the structure of cancellous bone has been addressed in the past by histomorphometry and more recently by imaging techniques using X-ray attenuation. The current approaches compute and describe parts of the construction of the trabecular net. We developed a new technique which quantifies cancellous bone of human lumbar vertebrae as a whole. The interactions, transactions, and interrelationships of all parts of the structural composition of the trabeculae are accounted for and quantified. The method is based on the concept of structural complexity within the framework of nonlinear dynamics. The methodology was developed by using axial high resolution computed tomography images. The technique was transferred to quantitative computed tomography images and is based on the non-invasive assessment of 50 human L3 specimens. The value of Houndsfield units per pixel representing trabecular bone of the vertebrae was transformed into color-encoded and alphabet-encoded symbols. The procedure of transformation of the X-ray attenuation pixels into symbols was necessary as a basis on which measures of complexity were introduced to assess the composition of symbols within the images. The development of a generalization of symbolic dynamics, a mathematical method, to work with two-dimensional images was a prerequisite. The results of this study demonstrate that the structural composition of cancellous bone declines more rapidly than bone mineral density during the loss of bone. This outcome strongly suggests an exponential relationship between bone mineral density and the architectural composition of cancellous bone. Normal trabecular bone has a complex ordered structure. The structural composition during the osteopenic phase of bone loss is characterized by lower structural complexity and a significantly higher level of architectural disorder. A high grade of osteoporosis leads again to an ordered structure, although its structural complexity is minimal.

Background: The prevalence of radiographically defined vertebral deformities, as a marker of vertebral osteoporosis, was calculated in a population based cross-sectional survey in Germany., Method: Lateral spine X-rays were taken according to a standardized protocol and evaluated centrally. Three thousand nine hundred and eighty subjects (2064 male and 1916 female) aged 50 to 79 years, have been examined in 8 German centers., Results: Based on McCloskey's method of deformity definition the age-standardized mean prevalence of vertebral deformities in Germany was 10.2% for males and 10.5% for females. Based on the definition by Melton/Eastell a significant higher prevalence was calculated (males 17.8%, females 18.7%). The prevalence increased with age in both sexes with a steeper increase in females. There was no difference in East and West German populations. There were substantial variations between the centers regarding the prevalence of deformities in females and males.

The European Vertebral Osteoporosis Study (EVOS) is one of the largest studies to investigate the prevalence of osteoporosis related vertebral fractures in a population based cross-sectional study. One of the main tasks was to create standards and logistics to obtain uniform and comparable radiographs in all 36 European centers. Furthermore the central reading of the X-rays and the morphometry of the vertebral bodies were 2 important challenges. This paper describes the standardized patient positioning and making of the radiographs as well as their morphometry, reading, and evaluation.

Purpose: The accuracy and reproducibility of morphometric measurements (Morphometric X-ray Absorptiometry = MXA) of vertebrae were determined. The significant difference of the change in height of vertebral bodies in follow-up studies was computed for MXA methods and digitised spinal radiographs as well., Material and Methods: The measurements were carried out on two new Dual X-ray Absorptiometry (DXA) devices (device A = Expert, Lunar Corp., device B = QDR 2000 Plus, Hologic Inc.). The data were obtained by using the European Spine Phantom (ESP) and lumbar spine specimens., Results: The accuracy of vertebral morphometry performed on radiographs is 2.0%, on the device A 2.3%, and on the device B 4.9%. Measurements taken with the ESP showed a reproducibility of 1.0 to 3.0%, whereas measurements of fractured vertebrae resulted in 5.1 to 6.0%., Conclusion: The results of the morphometric measurements demonstrate that a reliable fracture analysis in phantoms and specimens is possible. Further in-vivo studies are necessary.

The radiological diagnosis of osteoporosis is primarily based on osteodensitometry. The continuous development of new methods requires persistent analysis of its potential and limits. The knowledge of the differences of osteodensitometric methods is essential for understanding patient reports. The acronyms are internationally established, their correct usage is advocated.

Today the indication of hysterosalpingography is supplied via radiography in the diagnosis of female infertility patients. Hence, a different group of patients is now selected in contrast to the previous indications. The venous intravasation in uterine and adnexal vessels among infertility patients was observed in only 0.4% of our cases. The relationship between the changed indication, the technique of HSG, the changed permeability of the vessels after surgery, and the rare occurrence of intravasation is discussed.

In 83 of 86 patients with multiple sclerosis (MS) cranial magnetic resonance imaging (MRT) demonstrated lesions consistent with the clinical diagnosis. All the patients had either clinically typical MS oralaboratory-confirmed diagnosis of MS. The sensitivity of MRI is compared to those of computed tomographic (CT) scanning, evoked potential testing and cerebrospinal fluid analysis. The features of MS revealed by MRI are interpreted in terms of the macroscopic pathology and correlated with the clinical findings. The importance of particular findings (cystic appearance of lesions, spread of periventricular patches into the centrum semiovale) for the patients prognosis in stressed.

The case of a 29-year-old female patient is presented as an example of formation and resorption of a post-traumatic intrapulmonary hematoma. This case is compared with the findings in the literature and discussed. The importance of diagnostic differentiation from malignant coin lesions is pointed out.

Magnetic resonance imaging (MRI) has the advantage of high sensitivity compared to other diagnostic imaging techniques in focal pathological lesions of the brain in multiple sclerosis patients. However, the specificity of this examination method is limited. Diseases of the central nervous system due to other, different causes could produce a similar magnetic resonance image. Clinically examined cases of malignant and toxic affections of the brain caused by inflammatory, degenerative, traumatic and vascular diseases are presented and compared with the changes occurring in multiple sclerosis.

175 patients with definite multiple sclerosis underwent nuclear magnetic resonance imaging. T1-weighted images showed in 59 patients (34%) periventricular lesions with a central area of decreased signal intensity. They appear as lacunar defects in the walls of the lateral ventricle system. In accordance with neuropathological findings we suggest that in these plaques a cystic degeneration has replaced gliosis. Patients with cystic defects are characterized by a high activity of the disease (e.d. increased annual production of plaques) and a poor prognosis. Lacunae are found in the early stages of the disease and provide a prognostic sign in multiple sclerosis.

The vertebral veins and their anastomoses to the other venous vascular regions are represented in their anatomy, physiological and pathophysiological function, with a special reference to the spreading of tumor cells through the veins of the vertebral column. The causes of the accumulation of metastases in the trunk skeleton and brain is pointed out by malignant tumors of the prostata, of the ren, of the lung, of the mamma, of the genital organs and the thyroid gland. The signification of the vertebral venous system as a spread of metastases is emphasized under consideration of the tumor cell kinetics in the blood-flow and the different forms of the metastatic formations, and is verifying by experienced clinical cases and reviews of the literature.