9 results
1 - Introduction
-
- By Richard Towbin, University of Arizona, Kevin M. Baskin, University of Pittsburgh Medical Center, David Aria, Phoenix Children's Hospital, Robin Kaye, University of Arizona
- Edited by Richard Towbin, Kevin Baskin
-
- Book:
- Pediatric Interventional Radiology
- Published online:
- 05 June 2015
- Print publication:
- 18 June 2015, pp 1-21
-
- Chapter
- Export citation
-
Summary
History
The subspecialty of interventional radiology has its roots in the late 1950s and early 1960s with the development of catheterization techniques for cardiovascular angiography. The following two decades resulted in a remarkable growth and development of both diagnostic radiologic techniques and biologically compatible materials. This evolution of equipment and methodology has played a major role in the development, acceptance, and utilization of interventional radiology.
Cross-sectional imaging with ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) has, in most instances, allowed the radiologist to accurately localize and describe a pathologic process anywhere in the body. More recently, the addition of positron emission tomography (PET) has allowed radiologists to observe the regional physiology of a lesion and help plan interventional procedures accordingly. Using these powerful imaging techniques, the interventionalist can plan the safest approach to the lesion and target the most active region while avoiding uninvolved structures.
The development of new devices, especially in small sizes, has led to an ever-increasing number of non-vascular and vascular interventional procedures in the pediatric population. The advances in materials were generally targeted for use in the adult population. However, it was not long until children were also benefiting as a result of the creativity of interventionalists working with all ages and sizes of pediatric patients. Over the last several years there has been a substantial increase in the number of interventionalists specifically trained to treat children as well as a rapid growth in the number of interventional procedures being performed.
An overview of our practice growth over the last three decades defines the changes that have occurred in the field. In the late 1970s we began to make the transition in the name of the specialty from special procedures to interventional radiology. In the early years the practice consisted mainly of the “ographies” – diagnostic angiography, myelography, arthrography, etc. In this period a busy service might do 50 to 75 cases per year. The introduction of cross-sectional imaging with CT and US significantly propelled the field of pediatric interventional radiology forward.
8 - Vascular interventions
-
- By Richard Towbin, University of Arizona, Kevin M. Baskin, University of Pittsburgh Medical Center, David Aria, Phoenix Children's Hospital, Carrie Schaefer, University of Arizona
- Edited by Richard Towbin, Kevin Baskin
-
- Book:
- Pediatric Interventional Radiology
- Published online:
- 05 June 2015
- Print publication:
- 18 June 2015, pp 404-476
-
- Chapter
- Export citation
-
Summary
General angiographic considerations
Introduction
Most vascular interventional techniques that were initially developed for the treatment of adult vascular disease can be applied to the pediatric patient, providing appropriate technical modifications are made. There are issues specific to pediatric patients that require consideration in order to safely and successfully use vascular interventional techniques in this population. The problems that need to be overcome include the small patient size, the child's inability to cooperate, vulnerability to hypothermia and blood loss, volume limits for fluids and contrast media, the small size and fragility of access vessels, and, in the neonate, physiological differences related to fetal circulation. The wide range of patient sizes and clinical indications require that the operator be familiar with the vascular problems affecting children and techniques required to treat them. In addition, the interventionalist should be experienced with pediatric sedation and resuscitation, fluid administration, drug dosages, and contrast injection volumes for children of all ages and sizes. Catheterization supplies including needles, guide wires, sheaths, and other materials must be available in a range of sizes appropriate to the child being treated, and the operator should be familiar with the technique of custom shaping of catheters.
Indications
A large proportion of angiographic studies in the pediatric population are performed in conjunction with endovascular therapies (Table 8.1).
Current indications for diagnostic cerebral angiography include central nervous system (CNS) vasculitis, hemorrhage, cerebral ischemia, trauma, and investigation of vascular malformations, strokes, and vasospasm prior to endovascular therapy. Visceral angiography is most commonly indicated to investigate and treat hypertension, ischemia or occlusion related to organ transplantation, gastrointestinal bleeding, hemorrhage after penetrating or blunt trauma, varicoceles, and vascular malformations. Indications for extremity angiography include vascular mapping prior to surgical reconstruction of complex hand and foot anomalies, following penetrating injury and to investigate ischemic vasculopathy. In addition to the investigation of congenital heart disease, thoracic angiography is needed to study and treat hemoptysis, cyanosis (e.g., pulmonary AV malformations), and pulmonary embolism.
6 - Genitourinary interventions
-
- By Richard Towbin, University of Arizona, Kevin M. Baskin, University of Pittsburgh Medical Center, David Aria, Phoenix Children's Hospital
- Edited by Richard Towbin, Kevin Baskin
-
- Book:
- Pediatric Interventional Radiology
- Published online:
- 05 June 2015
- Print publication:
- 18 June 2015, pp 297-355
-
- Chapter
- Export citation
-
Summary
History
Minimally invasive techniques are well suited for use in the child's urinary tract. As a result, the urinary tract was one of the initial systems to be treated using a percutaneous approach. In spite of the numerous percutaneous procedures that are currently available to diagnose and treat problems involving the urinary tract, it is this area of interventional practice that has grown the least in the past decade. The relatively limited involvement by interventional radiologists is likely due to a variety of factors including the preference of urologists to perform combined percutaneous and surgical procedures in the operating room.
As is the case in other systems, interventional procedures in the genitourinary system result in less pain, shorter hospital stays, and faster recovery than open surgical alternatives. In addition, in most hospitals there is a shorter time between request for and performance of the procedure with lower cost than open surgery. Despite these factors, referrals to the interventional service favor children with failed surgical procedures, after-hours procedures, or other difficult cases. A willingness to help with these cases often leads in time to more frequent referral of the many children who could benefit from image-guided therapy that are not currently being seen by the pediatric interventionalist for routine procedures.
Anatomic considerations
To successfully perform genitourinary procedures a fundamental understanding of the anatomy of the kidneys, including the peculiarities of renal vascular and morphologic anomalies and post-transplant relationships, is essential to maximize desirable outcomes while avoiding complications. While a complete review is beyond the scope of this text, the reader is encouraged to seek out some of the excellent texts and monographs that focus on this material.
With their long axis aligned with the psoas muscles, the kidneys are normally located between T12 and L2 to L3, although with ectopia they may be positioned anywhere between the thorax and the pelvis in the retroperitoneum. Their lateral borders are normally rotated 30 degrees posterior to the frontal plane. Kidneys may be malrotated, fused (horseshoe kidney), duplicated, ectopic (crossed-fused renal ectopia), dysplastic, or unilaterally absent (agenesis).
5 - Hepatobiliary interventions
-
- By Kevin M. Baskin, University of Pittsburgh Medical Center, Richard Towbin, University of Arizona, David Aria, Phoenix Children's Hospital, Robin Kaye, University of Arizona
- Edited by Richard Towbin, Kevin Baskin
-
- Book:
- Pediatric Interventional Radiology
- Published online:
- 05 June 2015
- Print publication:
- 18 June 2015, pp 250-296
-
- Chapter
- Export citation
3 - Thoracic interventions
-
- By Richard Towbin, University of Arizona, Kevin M. Baskin, University of Pittsburgh Medical Center, David Aria, Phoenix Children's Hospital, Carrie Schaefer, University of Arizona
- Edited by Richard Towbin, Kevin Baskin
-
- Book:
- Pediatric Interventional Radiology
- Published online:
- 05 June 2015
- Print publication:
- 18 June 2015, pp 97-150
-
- Chapter
- Export citation
-
Summary
History
In the past, relatively few thoracic interventional procedures were performed in the pediatric population. The majority of thoracic procedures have been performed by physicians and surgeons in their offices, on the wards, in emergency rooms, and in the clinics. This appears to be changing. Interventionalists, using image guidance, are now performing an increasing number of diagnostic and therapeutic procedures. Traditionally, most thoracic procedures involved diagnostic aspiration (thoracentesis), drainage of pleural fluid, or biopsy of pulmonary lesions. Recently, more complex interventions involving the tracheobronchial tree have become possible. The availability of high-quality ultrasound (US), computed tomography (CT), and to a lesser extent magnetic resonance imaging (MRI), has led to a wider range and larger number of procedures being performed each year.
Interventional radiology and thoracic interventions
To achieve maximal involvement, the interventionalist needs to play an active role in the patient care team. It is important to work closely with pediatricians, oncologists, cardiologists, pulmonologists, general and cardiovascular surgeons, and others, to clearly define the goals of each procedure and develop a treatment plan. As the treatment plan is tailored to each child's needs, attention to detail is critical for a successful outcome.
Three important features of the thoracic region bear directly on management decisions for image-guided therapy. First, the bony thorax may limit the use of US. Therefore transducer selection is important. Whenever possible, use of a higher frequency transducer with a small footprint is recommended. Second, air-filled lung also limits sonographic visualization. Thus the risks associated with transgression of pleura and lung parenchyma may not be predicted with US guidance. However, there are situations where US can be useful, such as for visualization of pleural and subpleural lesions and mediastinal pathology, and for evaluation of pulmonary masses or other pathology when non-aerated lung is interposed between the target and the pleura.
4 - Abdominopelvic interventions
-
- By Kevin M. Baskin, University of Pittsburgh Medical Center, Richard Towbin, University of Arizona
- Edited by Richard Towbin, Kevin Baskin
-
- Book:
- Pediatric Interventional Radiology
- Published online:
- 05 June 2015
- Print publication:
- 18 June 2015, pp 151-249
-
- Chapter
- Export citation
-
Summary
Introduction
Patient problems in the abdomen and pelvis demand the fullest expression of clinical interventional radiology. From acute trauma to chronic renal failure, from solid organ biopsy to dilation of hollow viscera, from gastrojejunostomy tube exchange to transgastric drainage of a pancreatic pseudocyst, abdominopelvic interventional procedures can challenge practitioners on every level: intellectually, technically, emotionally, and ethically.
Virtually any problem in this region can be solved by distinctly different methods and with use of a variety of imaging approaches. For example, a pelvic fluid collection may be accessible from transrectal, transgluteal, or percutaneous access, using ultrasound, CT, or fluoroscopy, or a combination of multiple modalities. One may use a straight needle, a curved needle, or no needle at all (in the case of trocar access). These and many other choices are available to the interventionalist, and solutions must be individualized to each patient presentation.
Perhaps one of the most essential questions the interventional radiologist must answer is to what degree he or she will become integrated into the patient's total care. One can limit a practice to the provision of technical expertise in the performance of procedures on demand. It is our belief, professed throughout this text, that our involvement in patient care should ideally begin with consultation for assessment and planning at the time of initial presentation, and should end when the problem for which we have been consulted has been resolved, for problems that fall within our scope of practice, in a manner and by a process that is indistinguishable from any other procedure-based practitioner. It is to this end that this chapter is directed.
Gastrostomy and related procedures
Introduction
Adequate nutrition is essential for normal growth and development. In order for children with chronic illnesses or those who are unwilling or unable to take in adequate calories or essential nutrients to thrive, nutritional supplementation is necessary. In children with normal digestive function it is preferable to utilize the gastrointestinal (GI) tract for feeding to avoid hyperalimentation and its complications.
7 - Musculoskeletal and soft tissue interventions
-
- By Kevin M. Baskin, University of Pittsburgh Medical Center, Richard Towbin, University of Arizona, David Aria, Phoenix Children's Hospital, Carrie Schaefer, University of Arizona
- Edited by Richard Towbin, Kevin Baskin
-
- Book:
- Pediatric Interventional Radiology
- Published online:
- 05 June 2015
- Print publication:
- 18 June 2015, pp 356-403
-
- Chapter
- Export citation
-
Summary
History
In the past, the primary approach to diagnostic and therapeutic procedures involving the musculoskeletal (MSK) system has been open surgery by orthopedic surgeons, with the exceptions of joint aspiration and arthrography. Over time an increasingly broad range of these procedures are carried out using image-guided approaches, and consequently interventional radiologists are exercising a larger role, both in procedural collaboration with the orthopedic surgeons, neurosurgeons, rheumatologists, and other related proceduralists, as well as a more substantial role in clinical consultation for evaluation and management of relevant patients. It is in the MSK system that the modular approach to procedure development has worked particularly well, and this has led to an increasing diversity of patient problems that fall within the scope of practice of the pediatric interventionalist and an increasingly fertile area for innovation and collegial development of creative solutions. It is likely that this trend will continue and over time there will be fewer open procedures performed and increasing integration of interventional involvement in the care of these patients.
Interventional radiology and musculoskeletal interventions
Team approach
Interventions for problems that involve the MSK system and soft tissues can often be accomplished with improved out-comes, less surgical trauma, and a shorter recovery time if image-guided techniques are used compared to traditional open surgical approaches. For example, traumatic fracture of the pelvis with both anterior and posterior instability has traditionally been treated using a large anterior incision and plating across the reduced sacroiliac (SI) fracture. The same objective, stabilization of the posterior ring instability, can be accomplished through a small posterolateral incision with image-guided placement of one or more screws across the SI fracture after closed reduction of the dislocation. Details and advantages of this procedure are outlined below under “Orthopedic interventions.” Because of the infrequency of this problem, interventionalists seldom have a depth of experience with the required hardware and delivery systems, while orthopedic surgeons usually lack training with sophisticated cross-sectional image guidance.
Collaboration allows optimal application of asymmetric skill sets to optimize high-quality outcomes not easily achieved by either subspecialty in isolation.
2 - Central venous access
-
- By Kevin M. Baskin, University of Pittsburgh Medical Center, Richard Towbin, University of Arizona
- Edited by Richard Towbin, Kevin Baskin
-
- Book:
- Pediatric Interventional Radiology
- Published online:
- 05 June 2015
- Print publication:
- 18 June 2015, pp 22-96
-
- Chapter
- Export citation
-
Summary
History
The history of venous cannulation extends over 250 years. Intravenous therapy was first performed in children in the 1940s. In 1973, Broviac and associates introduced the tunneled silicone central venous catheter (CVC) for prolonged hyper-alimentation. Six years later, Hickman and colleagues presented an alternative to the Broviac right atrial catheter with a larger lumen. The Hickman catheter has subsequently gained popularity for a broader range of indications. Initially, tunneled right atrial catheters were inserted by surgical cut-down of the proximal cephalic vein and subcutaneous tunneling to the anterior chest wall. However, this approach was not always successful because of the small caliber of the cephalic vein. Thus, cut-down of the larger and more central internal or external jugular veins was introduced in the early 1980s, and soon after methods were described for percutaneous insertion of subclavian venous catheters. Over the years, surgical techniques have been adapted so that central lines could be inserted percutaneously without and with imaging guidance.
Interventional radiology and CVC insertion
In the past, interventionalists were primarily consulted to evaluate and treat catheter dysfunction or catheter-related complications, through diagnostic venography as well as image-guided redirection of malpositioned catheters and retrieval of intravascular catheter fragments. Advances in imaging, especially sonography, and in interventional techniques allowed interventionalists to gain venous access even in patients whose major venous pathways (jugular, subclavian, and femoral) had become occluded. In the late 1980s, surgical techniques for placement of central lines were adapted to allow for primary percutaneous insertion. Since that time, successful placement of CVCs in angiography suites has become the norm in virtually all facilities worldwide where interventional services are available. The percutaneous technique is equally adaptable for both children and adults. Over the last few years, referrals for insertion of CVCs have increased dramatically. In many large pediatric centers, pediatric interventionalists provide leadership of the multispecialty coalition responsible for the many diverse aspects of care of the complex population of patients who require central venous access. Image-guided percutaneous insertion of central and peripheral catheters for venous access is now the fastest growing segment of pediatric interventional practice.
8 - Ischemia in children
- Edited by Heike E. Daldrup-Link, University of California, San Francisco, Charles A. Gooding, University of California, San Francisco
-
- Book:
- Essentials of Pediatric Radiology
- Published online:
- 06 December 2010
- Print publication:
- 02 September 2010, pp 220-255
-
- Chapter
- Export citation