Gastrointestinal intervention in children

Interventional radiology is a rapidly growing discipline in paediatrics. Many non-vascular interventional techniques may be used in the gastrointestinal tract in children. The technically simpler and more common of these may be adopted by any paediatric radiologist with an interest in interventional radiology. Other rarer and more complex techniques are currently restricted to specialist centres with a higher overall caseload. This review emphasizes the common procedures such as oesophageal dilatation, gastrostomy, insertion of transgastric jejunal feeding tubes and biopsy. Less common salivary, hepatobiliary, pancreatic and intestinal interventions are also described.

[Radiology: from diagnostic tool to interventional procedures]

This article represents the author's personal view and experience on the gradual shift from diagnostic to interventional radiology during the past 30 years. The first interventional procedures almost exclusively concerned vascular medicine. Progress in cross-sectional imaging with ultrasound, CT and MRI opened opportunities for further applications such as abdominal and musculoskeletal interventional procedures. Interventional radiology takes place in a grey area between specialties. Interspecialty turf battles can be the result, often at the expense of the interests of the patient. Training programmes have been devised that can be followed by professionals from different specialties, and it may be expected that physicians other than radiologists could perform radiological interventions, at least in part. This development should stimulate close cooperation between specialties, rather than the exclusive claiming of certain procedures. The progress of interventional radiology has benefitted from the multidisciplinary approach to clinical problems; this multidisciplinary approach should also be the basis for future developments in minimally invasive image-guided interventional procedures.

New approaches to catheter navigation for interventional radiology simulation

For over 20 years, interventional methods have improved the outcomes of patients with cardiovascular disease. However, these procedures require an intricate combination of visual and tactile feedback and extensive training. In this paper, we describe a series of novel approaches that have led to the development of a high-fidelity simulation system for interventional neuroradiology. In particular, we focus on a new approach for real-time deformation of devices such as catheters and guidewires during navigation inside complex vascular networks. This approach combines a real-time incremental Finite Element Model (FEM), an optimization strategy based on substructure decomposition, and a new method for handling collision response in situations where the number of contact points is very large. We also briefly describe other aspects of the simulation system, from patient-specific segmentation to the simulation of contrast agent propagation and fast volume-rendering techniques for generating synthetic X-ray images in real time. Although currently targeted at stroke therapy, our results are applicable to the simulation of any interventional radiology procedure.

Trends in workforce diversity in vascular surgery programs in the United States

BACKGROUND

U.S. black and Hispanic populations are growing at a steady pace. In contrast, the medical profession lacks the same minority growth and representation. Women are also under-represented in many surgical disciplines. The purpose of this study was to assess trends in the proportion of women, blacks, and Hispanics admitted to vascular surgery (VS) and related specialties, and to compare them with each other and with a surgical specialty, orthopedic surgery (OS), with a formal diversity initiative.

METHODS

Data on the fellowship pool of VS, interventional radiology (IR), and interventional cardiology (IC), as well as the resident pools of general surgery (GS) and orthopedic surgery (OS), were obtained from U.S. graduate medical education reports for 1999 through 2005. Cochrane-Armitage trend tests were used to assess trends in the proportion of females, blacks, and Hispanics in relation to the total physician workforce for each subspecialty.

RESULTS

No significant trends in the proportion of females, blacks, or Hispanics accepted into VS and IC fellowship programs occurred during the study period. In contrast, IR, GS, and OS programs revealed significant trends for increasing proportions of at least one of the underrepresented study groups. In particular, OS, which has implemented a diversity awareness program, showed a positive trend in female and Hispanic trainees (P < .04 and P < .02, respectively). Blacks showed a significant increasing trend only in IR (P = .05). Conversely, a positive trend toward continued growth in the Hispanic group was seen in GS (P < .001), IR, and OS (P = .04 and P = .02, respectively).

CONCLUSIONS

The racial/ethnic and gender composition of the physician trainee pool in vascular specialties, particularly VS, has not matched the increasing growth of underrepresented groups in the US population of patients with vascular disease. Formal programs to recruit qualified women and minorities appear successful in increasing workforce diversity.

[Interventional neuroradiology. Current status--future prospects]

First developed in the 1960s, interventional neuroradiology has vastly improved the management of patients with vascular diseases of the brain and spine, including vascular malformations and stroke. Gradually replacing open-skull neurosurgical approaches, endovascular occlusion of ruptured intracranial aneurysms has improved the post-bleed prognosis. With the increasing number of fortuitously discovered aneurysms, international randomized studies are being organized to determine whether preventive treatment is better than abstention. A wide range of therapeutic strategies are available for brain arteriovenous malformations, including hyperselective embolization, open-skull surgery, radiosurgery, and abstention. The choice depends on multiple parameters, including symptoms, clinical status, the angioarchitecture of the malformation, and the patient's psychology and wishes (...).

One size (doesn't) fit all

The current radiology workflow model is inherently flawed by its emphasis on quantity over quality, limited accountability, and relative inflexibility of the technology. This adverse affect of technology inflexibility is of particular importance within radiology, because it is the single medical specialty completely dependent on technology for all its existence. For practicing radiologists, the human-computer interaction involves a multitude of individual events that collectively constitute the interpretation process. These individual workflow steps include image retrieval, display, presentation, navigation, processing, manipulation, decision support, and reporting. Considering the heterogeneous nature of the diverse population of end users, it is no surprise that the relative rigidity of the supporting technology creates a tremendous burden on radiologists' performance. The ideal scenario would be the creation of adaptive technology, which would consist of flexible and intuitive software that adapts to the unique needs and preferences of each individual end user, as well as the specific task at hand, while maintaining "best practice" guidelines. This interactive software would take into account a number of variables (education and training, computer experience, personality, visual perception, motor skills) to create user-specific profiles, which can be stored in a centralized database, independent of the specific vendor and technology being used. This user-specific software would also integrate affective computing technologies to dynamically adjust to end users' ever changing emotional states and stress levels. The end result would be the creation of intuitive technology that dynamically adapts to the changing needs and abilities of users, as opposed to the current inflexible technology paradigm.

Belgian Neuroradiology in 2007: where are we and where are we going to?

Neuroimaging is a sub-specialized field of radiology experiencing major and rapid changes in both the day-to-day clinical practice and the investigative field. In the present review article we summarize which are ongoing debates and challenges, and which are the domains of excellence of Belgian Neuroradiology.

What's new in target volume definition for radiologists in ICRU Report 71? How can the ICRU volume definitions be integrated in clinical practice?

The optimal definition of the size, shape and location of gross tumour volume is one of the most important steps in the planning of radiation therapy, and necessitates a proper understanding of the procedure from both the oncologic radiologist and the radiation oncologist. This overview reports on the different terms and concepts that have been recommended in the ICRU Reports for this purpose; the latest Report 71 focuses on both previously given recommendations, and especially on electron beam therapy. This paper also highlights some of the problems that are encountered in the use of the International Commission on Radiation Units and Measurements (ICRU) recommendations in clinical practice, and at the interface between the radiation oncologist and the diagnostic oncologist.

Image-based brachytherapy: a forum for collaboration between radiation oncologists and diagnostic radiologists

There has been increased interest in implementing image-guided brachytherapy to better define the structures of interest and assess the radiation dose distribution in tumors and surrounding normal tissues. This is particularly helpful in the treatment of pelvic malignancies such as cervix cancer and prostate cancer, in which the tumor lies in close relationship to the bladder and rectosigmoid. This provides a forum for the collaboration of diagnostic radiologists and radiation oncologists.

New methods for the management of esophageal varices

Bleeding from esophageal varices (EVs) is a catastrophic complication of chronic liver disease. Many years ago, surgical procedures such as esophageal transection or distal splenorenal shunting were the only treatments for EVs. In the 1970s, interventional radiology procedures such as transportal obliteration, left gastric artery embolization, and partial splenic artery embolization were introduced, improving the survival of patients with bleeding EVs. In the 1980s, endoscopic treatment, endoscopic injection sclerotherapy (EIS), and endoscopic variceal ligation (EVL), further contributed to improved survival. We combined IVR with endoscopic treatment or EIS with EVL. Most patients with EVs treated endoscopically required follow-up treatment for recurrent varices. Proper management of recurrent EVs can significantly improve patients’ quality of life. Recently, we have performed EVL at 2-mo (bi-monthly) intervals for the management of EVs. Longer intervals between treatment sessions resulted in a higher rate of total eradication and lower rates of recurrence and additional treatment.

Evidence-based Practice in Radiology: Steps 3 and 4—Appraise and Apply Interventional Radiology Literature

When introducing new interventional radiology techniques or devices, it is important to learn from previous experiences and to remember that there are numerous examples of new techniques that were initially enthusiastically promoted and then subsequently abandoned when early promise was not realized. Appropriateness of new or established interventional radiology techniques to specific clinical conditions must be determined from clinical experience, from communication with experts in the field and/or careful review of available medical literature, and on an individual patient basis by means of review of clinical notes and diagnostic imaging studies. Several paradigms for evidence-based practice (EBP) exist. One model proposes that a central specialized process involving academic centers should primarily construct valid guidelines to direct practice at all levels of medical practice ("top-down" model). An alternative model integrates "the best research evidence with clinical expertise and patient values" ("bottom-up" model). This article will focus on the bottom-up model and describe the use of EBP by individual practitioners or groups of practitioners in optimizing literature review and critical appraisal. EBP is applied to two scenarios as a means of deciding the appropriateness of introducing interventional radiology techniques in a community hospital setting. The authors will also briefly discuss other applications for EBP techniques in interventional radiology, including development of practice guidelines or policy to ensure appropriate and safe practices.

Modern trends in interventional radiology

OBJECTIVE

To review the current applications of Interventional Radiology (IR), outline newer technologies and techniques and emphasize the role of Interventional Radiologists as clinical practitioners.

BACKGROUND

IR is a clinical modality that makes use of imaging guidance for the performance of minimally invasive treatment. The development of new imaging technologies and interventional devices has greatly increased the number of medical conditions that may now be treated by IR.

SUMMARY

Promising new treatments in cancer therapy, the treatment of fibroids, venous access and spine interventions as well as advances in non-invasive vascular imaging, pharmacological therapies and peripheral arterial and venous interventions are providing exciting opportunities for IR, attracting significant patient interest and promising tremendous public benefit.