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Since the 1990s, hybrid imaging by means of software and hardware image fusion alike allows the intrinsic combination of functional and anatomical image information. This review summarises the state-of-the-art of dual-modality imaging with a focus on clinical applications. We highlight selected areas for potential improvement of combined imaging technologies and new applications. In the second part, we briefly review the background of dual-modality PET/CT imaging, discuss its main applications and attempt to predict technological and methodological improvements of combined PET/CT imaging. After a decade of clinical evaluation, PET/CT will continue to have a significant impact on patient management, mainly in the area of oncological diseases. By adopting more innovative acquisition schemes and data processing PET/CT will become a fast and dose-efficient imaging method and an integral part of state-of-the-art clinical patient management.

Since the 1990s, hybrid imaging by means of software and hardware image fusion alike allows the intrinsic combination of functional and anatomical image information. This review summarises in three parts the state-of-the-art of dual-technique imaging, with a focus on clinical applications. We will attempt to highlight selected areas of potential improvement of combined imaging technologies and new applications. In this first part, we briefly review the origins of hybrid imaging and comment on the status and future development of single photon emission tomography (SPECT)/computed tomography (CT). In short, we could predict that, within 10 years, we may see all existing dual-technique imaging systems, including SPECT/CT, in clinical routine use worldwide. SPECT/CT, in particular, may evolve into a whole-body imaging technique with supplementary use in dosimetry applications.

The development of powerful and comprehensive medical ontologies that support formal reasoning on a large scale is one of the key requirements for clinical computing in the next millennium. Taxonomic medical knowledge, a major portion of these ontologies, is mainly characterized by generalization and part-whole relations between concepts. While reasoning in generalization hierarchies is quite well understood, no fully conclusive mechanism as yet exists for part-whole reasoning. The approach we take emulates part-whole reasoning via classification-based reasoning using SEP triplets, a special data structure for encoding part-whole relations that is fully embedded in the formal framework of standard description logics.

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The rapid growth of diagnostic-imaging technologies over the past two decades has dramatically increased the amount of nontextual data generated in clinical medicine. The architecture of traditional, text-oriented, clinical information systems has made the integration of digitized clinical images with the patient record problematic. Systems for the classification, retrieval, and integration of clinical images are in their infancy. Recent advances in high-performance computing, imaging, and networking technology now make it technologically and economically feasible to develop an integrated, multimedia, electronic patient record. As part of The National Library of Medicine's Biomedical Applications of High-Performance Computing and Communications program, we plan to develop Image Engine, a prototype microcomputer-based system for the storage, retrieval, integration, and sharing of a wide range of clinically important digital images. Images stored in the Image Engine database will be indexed and organized using the Unified Medical Language System Metathesaurus and will be dynamically linked to data in a text-based, clinical information system. We will evaluate Image Engine by initially implementing it in three clinical domains (oncology, gastroenterology, and clinical pathology) at the University of Pittsburgh Medical Center.

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Since the 1990s, hybrid imaging by means of software and hardware image fusion alike allows the intrinsic combination of functional and anatomical image information. This review summarises in three parts the state of the art of dual-technique imaging with a focus on clinical applications. We will attempt to highlight selected areas of potential improvement of combined imaging technologies and new applications. In this third part, we discuss briefly the origins of combined positron emission tomography (PET)/magnetic resonance imaging (MRI). Unlike PET/computed tomography (CT), PET/MRI started out from developments in small-animal imaging technology, and, therefore, we add a section on advances in dual- and multi-modality imaging technology for small animals. Finally, we highlight a number of important aspects beyond technology that should be addressed for a sustained future of hybrid imaging. In short, we predict that, within 10 years, we may see all existing multi-modality imaging systems in clinical routine, including PET/MRI. Despite the current lack of clinical evidence, integrated PET/MRI may become particularly important and clinically useful in improved therapy planning for neurodegenerative diseases and subsequent response assessment, as well as in complementary loco-regional oncology imaging. Although desirable, other combinations of imaging systems, such as single-photon emission computed tomography (SPECT)/MRI may be anticipated, but will first need to go through the process of viable clinical prototyping. In the interim, a combination of PET and ultrasound may become available. As exciting as these new possible triple-technique—imaging systems sound, we need to be aware that they have to be technologically feasible, applicable in clinical routine and cost-effective.

Since the 1990s, hybrid imaging by means of software and hardware image fusion alike allows the intrinsic combination of functional and anatomical image information. This review summarises in three parts the state of the art of dual-technique imaging with a focus on clinical applications. We will attempt to highlight selected areas of potential improvement of combined imaging technologies and new applications. In this third part, we discuss briefly the origins of combined positron emission tomography (PET)/magnetic resonance imaging (MRI). Unlike PET/computed tomography (CT), PET/MRI started out from developments in small-animal imaging technology, and, therefore, we add a section on advances in dual- and multi-modality imaging technology for small animals. Finally, we highlight a number of important aspects beyond technology that should be addressed for a sustained future of hybrid imaging. In short, we predict that, within 10 years, we may see all existing multi-modality imaging systems in clinical routine, including PET/MRI. Despite the current lack of clinical evidence, integrated PET/MRI may become particularly important and clinically useful in improved therapy planning for neurodegenerative diseases and subsequent response assessment, as well as in complementary loco-regional oncology imaging. Although desirable, other combinations of imaging systems, such as single-photon emission computed tomography (SPECT)/MRI may be anticipated, but will first need to go through the process of viable clinical prototyping. In the interim, a combination of PET and ultrasound may become available. As exciting as these new possible triple-technique—imaging systems sound, we need to be aware that they have to be technologically feasible, applicable in clinical routine and cost-effective.

A deeper understanding of the role of specific genes, proteins, pathways and networks in health and disease, coupled with the development of technologies to assay these molecules and pathways in patients, promises to revolutionise the practice of clinical medicine. In particular, the discovery and development of novel drugs targeted to disease-specific alterations could benefit significantly from non-invasive imaging techniques assessing the dynamics of specific disease-related parameters. Here we review the application of imaging biomarkers in the management of patients with brain tumours, especially malignant glioma. This first part of the review focuses on imaging biomarkers of general biochemical and physiological processes related to tumour growth such as energy, protein, DNA and membrane metabolism, vascular function, hypoxia and cell death. These imaging biomarkers are an integral part of current clinical practice in the management of primary brain tumours. The second article of the review discusses the use of imaging biomarkers of specific disease-related molecular genetic alterations such as apoptosis, angiogenesis, cell membrane receptors and signalling pathways. Current applications of these biomarkers are mostly confined to experimental small animal research to develop and validate these novel imaging strategies with future extrapolation in the clinical setting as the primary objective.

The Hypertext atlas of Dermatopathology, the Atlas of Fetal and Neonatal Pathology and Hypertext atlas of Pathology (this one in Czech only) are available at . These atlases offer many clinical, macroscopic and microscopic images, together with short introductory texts. Most of the images are annotated and arrows pointing to the important parts of the image can be activated.

The Virtual Microscope interface is used for the access to the histological images obtained in high resolution using automated microscope and image stitching, possibly in more focusing planes. Parts of the image prepared in advance are downloaded on demand to save the memory of the user's computer. The virtual microscope is programmed in JavaScript only, works in Firefox/Mozilla and MSIE browsers without need to install any additional software.

AIMS--To determine if a clinically important polymorphonuclear leucocyte infiltrate and surface gastric epithelial metaplasia occur in the second part of the duodenum in coeliac disease; to evaluate the utility of these morphological criteria in the differential diagnosis of coeliac disease and peptic duodenitis. METHODS--49 mucosal biopsy specimens of the second part of the duodenum reported as showing inflammation were reviewed. Sections were prepared with haematoxylin and eosin, periodic acid Schiff, and Warthin-Starry stains. Clinical presentation, outcome, and immunological investigations were assessed. RESULTS--Four cases confirmed as coeliac disease on clinical and immunological grounds showed acute inflammation and surface epithelial gastric metaplasia. Increased intraepithelial lymphocytes (IELs) were found in each of the four. CONCLUSIONS--Clinically important polymorphonuclear leucocyte infiltration and surface epithelial gastric metaplasia may occur in the duodenal mucosa in coeliac disease and should not be used as diagnostic features to exclude the diagnosis of coeliac disease in the absence of confirmatory clinical and immunological information.

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This report is the third part of a trilogy from a multidisciplinary study which was undertaken to investigate gene and protein expression in a large cohort of patients with well defined and diverse clinical phenotypes. The aim of part 3 was to review which of the analytical techniques that we had used would be the most useful for differential diagnosis, and which would provide the most accurate indication of disease severity. Careful clinical appraisal is very important and every DMD patient was correctly diagnosed on this basis. In contrast, half of the sporadic BMD patients and all of the sporadic female patients had received different tentative diagnoses based on clinical assessments alone. Sequential observations of quantitative parameters (such as the time taken to run a fixed distance) were found to be useful clinical indicators for prognosis. Intellectual problems might modify the impression of physical ability in patients presenting at a young age. Histopathological assessment was accurate for DMD but differentiation between BMD and other disorders was more difficult, as was the identification of manifesting carriers. Our data on a small number of women with symptoms of muscle disease indicate that abnormal patterns of dystrophin labelling on sections may be an effective way of differentiating between female patients with a form of limb girdle dystrophy and those carrying a defective Xp21 gene. Dystrophin gene analysis detects deletions/duplications in 50 to 90% of male patients and is the most effective non-invasive technique for diagnosis. Quantitative Western blotting, however, would differentiate between all Xp21 and non-Xp21 male patients. In this study we found a clear relationship between increased dystrophin abundance (determined by densitometric analysis of blots) and clinical condition, with a correlation between dystrophin abundance and the age at loss of independent mobility among boys with DMD and intermediate D/BMD. This indicates that blotting is the most sensitive and accurate technique for diagnosis and prognosis.

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The nucleotide sequence of a 3.5-kb BamHI fragment from Listeria monocytogenes 12067, a human clinical isolate of serotype 4b, has been determined. The DNA fragment harbors the gene for listeriolysin, part of the gene for a phosphatidylinositol-specific phospholipase C, and part of the gene for a metalloprotease. Comparison of the sequence with corresponding sequences from two other L. monocytogenes isolates revealed a significant number of nucleotide differences. Several of the differences give rise to amino acid substitutions. The most variable region was the examined part of the mpl gene, whereas the lisA gene showed a relatively high degree of conservation, particularly at the amino acid level. To analyze the pattern of sequence variability in the lisA gene, a 160-bp region covering nine nucleotide differences was sequenced from 36 isolates of different origins. This work showed that the strains can be grouped into two major types according to the nucleotide sequences. Oligonucleotide probing of a larger number of L. monocytogenes isolates showed that the observed differences can be used to subdivide the species. The data suggest a correspondence between the sequence type of the lisA gene and flagellar antigens. Assays based on hybridization or the polymerase chain reaction with type-specific oligonucleotides may provide fast and easy alternative methods for strain typing.

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An anaerobic transport system (ATS) which provides for catalytic removal of oxygen was evaluated by using in vitro-prepared polymicrobial mixtures of logphase bacteria and clinical specimens. Inoculated swabs were stored at room temperature in (i) aerobic, (ii) anaerobic glove box, and (iii) ATS environments, and bacteria were quantitated after 2, 24, 48, and 72 h. Bacteria in a three-part mixture of Bacteroides fragilis, Peptostreptococcus anaerobius, and Escherichia coli and in a five-part mixture of B. fragilis, P. anaerobius, Fusobacterium nucleatum, Staphylococcus epidermidis, and Pseudomonas aeruginosa survived 72 h of storage in the ATS and anaerobic glove box environments, but the anaerobic species were inactivated in the aerobic storage except for B. fragilis in pure culture or in the three-part mixture. Changes in relative proportions among the species in a mixture were least in the ATS and anaerobic glove box environments and greatest during the aerobic storage, particularly in the five-part mixture. Bacteria present in pure or mixed culture in clinical specimens generally survived 72 h of storage in the ATS. These data indicate that changes in relative proportions occur with prolonged storage even under anaerobic conditions, but that the ATS would be most effective for preserving anaerobic bacteria and preventing drastic concentration changes and overgrowth of facultative and aerobic bacteria.

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Doctors may feel uncomfortable with the prospect of discussing a human immunodeficiency virus (HIV) antibody test with their patient. This is in part because they do not enquire about high risk activity as part of a medical history. With increasing medical and public awareness of both the clinical manifestations and social implications of HIV infection, it is important that all doctors receive guidance on how to deal with these issues. Counselling is not the usual term used to describe obtaining informed consent. In the general medical setting, tests for hepatitis B and syphilis are routinely carried out without specific consent even though results of these tests may have profound effects on both the patient and their sexual partners. However society and ethical considerations have made HIV testing different. HIV testing will inevitably become more widespread, and thus become a more routine part of patient investigation and management.

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Enabling a developing country to become self-sufficient in health care is a major feat. This two-part article outlines how a general practice training project was established in Uganda to prepare postgraduate students to work in rural hospitals. The first part looked at the setting, personnel, and facilities. Part 2 outlines the curricula and clinical practice.

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Herniation of the hindbrain occurs when the lowest parts of the cerebellum and sometimes part of the medulla are moved downwards through the foramen magnum, a pressure difference acting across the foramen magnum moulding the tissues into a plug. It is suggested that the clinical course in both adults and babies with spina bifida may be explained by the hindbrain hernia acting as a valve.

The term 'Chiari Type I deformity' is commonly used for an abnormality in which the tonsils and lowermost parts of the cerebellar hemispheres are prolapsed through a normal foramen magnum. Acute herniation may occur as a result of space-occupying lesions. Chronic herniation may be morphologically identical although it tends to be more severe. Sometimes it will produce few symptoms which often may be delayed so that the original causative lesion may not be apparent. Causes include bone softening, tumour, or previous meningitis. Birth injury is probably the commonest cause of the deformity, which presents clinically in adults.

In infants with severe forms of spina bifida a hindbrain herniation is present. This abnormality may be called 'Chiari Type II deformity' or Arnold—Chiari deformity and is an intra-uterine abnormality in which the fourth ventricle and medulla are grotesquely herniated before they are properly developed and the foramen magnum is enlarged.

The commonest clinical presentation of Chiari Type I deformity is syringomyelia, which is usually not diagnosed until adult life. Other presentations include syringobulbia, headache, oscillopsia, attacks of giddiness, lower cranial nerve palsies, and ataxia. Particularly characteristic are cough headache and cough syncope. Syringomyelia and syringobulbia in particular may be irreversible by the time they are diagnosed. Nevertheless, surgical decompression may be successful in relieving symptoms of headache, cough syncope, and long-tract compression; most cases of syringomyelia show some improvement and in others progression of the disease is arrested. Operative techniques for hindbrain herniation are discussed.

Chiari Type II deformity is probably responsible for the progression of hydrocephalus after birth in the majority of babies with spina bifida. Measurement of pressure in the cerebrospinal fluid above and below the foramen magnum shows that intermittent pressure difference is commonly present at times of neurological deterioration. Surgical decompression of the hernia in adults allows correction of the valvular effect, which may be monitored by pressure measurements. In babies the associated hydrocephalus is usually so gross that it requires separate treatment, but pressure monitoring may be of value in assessing the state of the disease.

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Uveitis is an ocular disease frequently encountered in dogs and cats. Its importance relates to the fact that it can induce severe ocular pain and or result in permanent loss of vision. In addition, uveitis can be the first or only manifestation of a systemic, life-threatening disease. Since uveitis can present in a manner similar to a number of other ocular conditions, it behooves the clinician to first establish a prompt, accurate diagnosis in order to give the appropriate prognosis and treatment.

The first part of this review includes applied anatomy and physiology of the uveal tract, followed by a description of the various etiological factors found in uveitis. The second part deals with clinical signs and findings in anterior and posterior uveitis and with the sequelae of this ocular inflammatory process. Lastly, the third part contains therapeutic guidelines and a list of comprehensive reviews on this major topic in veterinary ophthalmology.

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This study reviews the presentation, etiology, imaging characteristics and reasons for missed diagnosis of Andersson lesion (AL) and analyzes the surgical results of short segment fixation in the thoracolumbar region. This is a retrospective single center study. Fourteen patients (15 lesions) who were operated for AL were analyzed. The study was designed in two parts. The first part consisted of analysis of clinical and radiological features (MRI and radiographs) to highlight, whether definitive characteristics exist. The second part consisted of analysis of outcome of short segment fixation as measured by VAS, Frankel score, AsQoL index, and union, with assessment of complications. The follow-up was 42.33 ± 19.29 months (13 males and 1 female) with a mean age of 61.13 ± 19.74 years. There was predisposing trauma in five patients. There was a delay in presentation of the patients by 5.86 ± 2.50 months. There was misdiagnosis in all the cases, at primary orthopedic level (ten cases were put on anti-tuberculous treatment due to its MRI resemblance to infection) and all but one case at radiologist level. Radiographs and MRI had characteristic features in all cases, and MRI could detect posterior element affection in 14 lesions as against only 8 posterior lesions detected in radiographs. In all patients, there was a patient’s delay and/or physician’s delay to arrive at a diagnosis. Spinal fusion was seen in all the cases. Outcome measures of VAS, Frankel score, and AsQoL index showed significant improvement (P < 0.002). No major complications occurred. There is a lack of awareness of AL leading to misdiagnosis. Definite clinico-radiological features do exist in AL and short segment fixation is effective.

Patients with a lacunar stroke syndrome may have cortical infarcts on brain imaging rather than lacunar infarcts, and patients with the clinical features of a small cortical stroke (partial anterior circulation syndrome, PACS) may have lacunar infarcts on imaging. The aim was to compare risk factors and outcome in lacunar syndrome (LACS) with cortical infarct, LACS with lacunar infarct, PACS with cortical infarct, and PACS with lacunar infarct to determine whether the clinical syndrome should be modified according to brain imaging.
 As part of a hospital stroke registry, patients with first ever stroke from 1990 to 1998 were assessed by a stroke physician who assigned a clinical classification using clinical features only. A neuroradiologist classified recent clinically relevant infarcts on brain imaging as cortical, posterior cerebral artery territory or lacunar.
 Of 1772 first ever strokes, there were 637 patients with PACS and 377 patients with LACS who had CT or MRI. Recent infarcts were seen in 395 PACS and 180 LACS. Atrial fibrillation was more common in PACS with cortical than lacunar infarcts (OR 2.3, 95% confidence interval (95% CI) 0.9-5.5), and in LACS with cortical than lacunar infarcts (OR 3.9, 1.2-12). Severe ipsilateral carotid stenosis or occlusion was more common in PACS with cortical than lacunar infarcts (OR 3.5, 1.3-9.5); and in LACS with cortical than lacunar infarcts (OR 3.7, 1.1-12).
 In conclusion, patients with cortical infarcts are more likely to have severe ipsilateral carotid stenosis or atrial fibrillation than those with lacunar infarcts irrespective of the presenting clinical syndrome. Brain imaging should modify the clinical classification and influence patient investigation.



Multimodality medical imaging takes advantage of the strengths of different imaging modalities to provide a more complete picture of the anatomy under investigation. Many complementary modalities have been combined to form such systems and some are gaining use clinically. One combination that has not been developed, in large part due to technical difficulties, is a combined MR and ultrasound imaging system. Such a system offers the potential to combine the strengths of these modalities in a wide range of diagnostic and therapeutic applications. The goal of this study was to evaluate the feasibility of performing simultaneous multimodality ultrasound and MR imaging. An ultrasound imaging system capable of operation in a clinical MR imager was developed, and methods to perform simultaneous imaging were investigated. Simultaneous imaging was feasible without any mutual interference by either filtering the transmitted and received ultrasound signal, or by synchronizing data acquisition between the two imaging systems. Spatial registration between the two modalities was achieved by using a reference phantom with implanted glass beads in orthogonal planes. Excellent agreement was observed between spatial measurements of an object made with both modalities, and the feasibility of using this system in vivo was demonstrated in a rabbit model. Simultaneous ultrasound and MR imaging is achievable, and can provide complementary information about an object under investigation. This demonstration of technical feasibility and the development of a prototype system open up the potential to investigate the promising clinical applications of this combined technology.

INTRODUCTION

The study assessed whether there is a greater incidence of divarication of the recti and whether between-recti distance is greater in patients with abdominal aortic aneurysm (AAA).

PATIENTS AND METHODS

The study consisted of two parts: a radiological and a clinical assessment. All patients with a confirmed AAA on computerised tomography were included and compared with patients in whom AAA was excluded with imaging. Between-recti distance was measured using a computerised image viewer and clinical divarication was assessed by a surgical registrar or consultant.

RESULTS

In the radiological part of the study, 108 patients with AAA were compared with 84 with colorectal cancer. Median between-recti distance was 38 mm (range, 25–59 mm) in the AAA group and 27 mm (range, 20–44.5 mm) in the non-AAA group (P = 0.006). AAA diameter did not correlate with between-recti distance. The clinical study included 50 patients (25 AAA). The groups were well matched, with only a greater incidence of diabetes in the AAA group (20% vs 0%; P = 0.018). AAA patients were more likely to have clinically detected divarication of the recti (76% vs 36%; P = 0.004).

CONCLUSIONS

Patients with AAA have greater radiological and clinical evidence of divarication. It is suggested that patients with divarication be screened for AAA.

Background

Information systems can play a key role in care innovations including task redesign and shared care. Many demonstration projects have presented evidence of clinical and cost effectiveness and high levels of patient satisfaction. Yet these same projects often fail to become part of everyday clinical routines. The aim of the paper is to gain insight into a common paradox that a technology can meet the criteria for success set out at the start of the project yet fail to become part of everyday clinical routines.

Methods

We evaluated a telecare service set up to reduce the workload of ophthalmologists. In this project, optometrists in 10 optical shops made digital images to detect patients with glaucoma which were further assessed by trained technicians in the hospital. Over a period of three years, we conducted interviews with the project team and the users about the workability of the system and its integration in practice. Beside the interviews, we analyzed record data to measure the quality of the images. We compared the qualitative accounts with these measurements.

Results

According to our measurements, the quality of the images was at least satisfactory in 90% of the cases, i.e. the images could be used to screen the patients – reducing the workload of the ophthalmologist considerably. However, both the ophthalmologist and the optometrists became increasingly dissatisfied respectively with the perceived quality of the pictures and the perceived workload.

Through a detailed analysis of how the professionals discussed the quality of the pictures, we re-constructed how the notion of quality of the images and being a good professional were constructed and linked. The IT system transformed into a quality system and, at the same time, transformed the notions of being a good professional. While a continuous dialogue about the quality of the pictures became an emblem for the quality of care, this dialogue was hindered by the system and the way the care process was structured.

Conclusion

To conceptualize what telemedicine does in interdisciplinary work practices, a fine-tuned analysis is needed to assess how IT systems re-shape the social relations between professional groups. Such transformations should not be exclusively attributed to the technology itself or to the professionals working with it. Instead we need to assess these technologies through an empirically grounded study of the sociotechnical functioning of telemedicine.

This study is in two parts. In the first synovial fluid from 1892 patients with 14 different arthropathies was examined microscopically. Crystals of different types were identified and the disease distribution of these and various cell types, including several not previously reported in synovial fluid, have been described. These features have been used to derive a series of microscopic diagnostic criteria for each arthropathy. The criteria have been used in the second part of the study to examine synovial fluids from 200 patients without knowledge of any clinical diagnosis. Cytological and clinical diagnoses were compared at the end of the study. Matching diagnoses were made in 71 (35.5%) and a short list of differential diagnoses (based on cytological criteria), which included the clinical diagnosis, was made in a further 43 (21.5%). Of the rest, 63 (31.5%) were correctly described as inflammatory or non-inflammatory and in five (2.5%) no diagnosis could be made. Only in seven cases (3.5%) was an inaccurate (false positive) cytological diagnosis made. The results indicate that synovial fluid microscopy is a potentially more important diagnostic screening test in rheumatological and orthopaedic practice than it would at first appear from published reports.

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A prospective clinical and radiological correlation study was performed to determine the frequency, and the clinical and radiological features of callosal infarction. From 1 January 1993 to the end of December 1993 282 cases of cerebral infarction seen in the Neurology service of the University Hospital of Dijon were studied prospectively. Eight cases with callosal ischaemic lesions were identified by CT and MRI. A callosal disconnection syndrome occurred in only five of eight patients, related to a single, large infarct or several infarctions in the anterior part of the corpus callosum. Clinical features were characterised by left ideomotor apraxia, construction apraxia, and left agraphia in all five cases. Alien hand was noted in only two cases. There were gait disorders in three cases with MRI features of multiple lacunes in a large part of the corpus callosum, and also the subcortical areas of both hemispheres. It is emphasised that callosal infarctions are not rare and that they contribute to the clinical features of strokes. As well as the classic incomplete callosal disconnection syndrome, these callosal ischaemic lesions may induce non-specific gait disorders.

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With the ageing population in most countries, disorders of bone and mineral metabolism are becoming increasingly relevant to every day clinical practice. Consequently, the interest in, and the need for effective measures to be used in the screening, diagnosis and follow-up of such pathologies have markedly grown. Together with clinical and imaging techniques, biochemical tests play an important role in the assessment and differential diagnosis of metabolic bone disease. These biochemical indices are non-invasive, comparatively inexpensive and, when applied and interpreted correctly, helpful tools in the diagnostic and therapeutic assessment of metabolic bone disease.

This second part of the two part series reviews the current evidence regarding the clinical use of biochemical markers of bone remodelling in the management of osteoporosis.

Venous thromboembolism (VTE) remains a serious problem, and treatments surrounding this potentially life-threatening disease continue to evolve. Evidence-based guidelines purport the need for minimally invasive catheter-based procedures as part of the armamentarium to prevent and treat VTE. When the appropriate clinical scenarios arise, intravascular ultrasound (IVUS) becomes a necessary part of those procedures to provide alternative imaging that complements traditional venography. IVUS of the major axial veins provides a 360-degree two-dimensional gray scale ultrasound image of lumen and vessel wall structures. IVUS remains the criterion standard for venous imaging when contemplating catheter-based procedures from the common femoral vein to the inferior vena cava. Not only can precise location and size of these veins be determined by the IVUS probe from key landmarks and venous branches, but other important abnormalities can be visualized. These include external compression, acute and chronic thrombus, fibrosis, mural wall thickening, spurs, and trabeculations. Specific procedures that use IVUS include the treatment of venous obstruction and the placement of vena cava filters at the bedside. IVUS remains a vital part of accurately imaging the major axial veins when contemplating catheter-based procedures to prevent or treat VTE-related disorders.