Pediatric Chest Imaging - part 3 pps

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Pediatric Chest Imaging - part 3 pps

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distress usually proceed to surgery. Older children and adults with recurrent pneumonia are also re- commended for surgery. The management of those patients with a radiologic CCAM who remain asymp- tomatic is less clear-cut. Certainly, there is a risk of infection developing in a CCAM and there are also several case reports of malignancy arising in CCAM. Bronchoalveolar carcinoma, pleuropulmonary blas- toma, rhabdomyosarcoma, and bronchogenic carci- noma have all been reported [6,15,21 –26]. Some authors advocate surgery in these patients, to eradi- cate the risk of future infection or tumor. Other Fig. 4. (A) Type II congenital cystic adenomatoid malformation in an asymptomatic neonate (antenatal diagnosis). Chest radiograph shows a hazy opacity in the right lower lobe and upward bowing of the minor fissure. (B) CT chest (lung windows) confirms the presence of several small cysts in the right lower lobe. This infant was managed conservatively. Fig. 3. (A) Type I congenital cystic adenomatoid malformation in a 12-month-old boy who presented with shortness of breath. Chest radiograph shows a hyperlucent right hemithorax, with contralateral shift of the heart and mediastinal structures. Sparse lung markings are seen in the right hemithorax. (From Donnelly LF. Chest. In: Fundamentals of pediatric radiology. Philadelphia: WB Saunders; 2001. p. 38.) (B) CT scan of the chest (lung windows) demonstrates a large cyst filling the right hemithorax. The compressed right middle lobe is seen behind the sternum. paterson306 Technique of Pediatric Thoracic CT Angiography Donald P. Frush, MD Division of Pediatric Radiology, Department of Radiology, Duke University Health System, 1905 McGovern-Davison Children’s Health Center, Box 3808, Erwin Road, Durham, NC 27710, USA One of the principle applications derived from the evolution of multidetector row CT (MDCT), initially seen with 16-slice and currently up to 64-slice CT, is CT angiography. The ease, safety, and quality of the examinations compared with traditional angiography were quickly recognized, and the value of CT angiography firmly established. For a variety of reasons, the earliest MDCT angiography with single- slice technology was problematic for the pediatric population [1–4]. Some of these problems included breathing artifact in children who could not hold their breath, small volumes of contrast material, relatively slow and inconsistent rates of injection, and small cardiovascular structures [4]. Although these same issues currently exist with pediatric CT angiography, much faster scanning and isotropic display with submillimeter image thickness have, to a large extent, minimized the impact of these factors. Nevertheless, it is still important to understand the special consid- erations with pediatric CT angiography [5]. In trying to make a potentially complex technique relatively simple and practical, the following material is divided into two parts: study preparation and study perform- ance. The format is essentially step-by-step (Box 1), with the supporting technical information either cited or included in tables. Despite the fact this material somewhat betrays the traditional academic format, a greater benefit is served: excellent CT angiography is possible in even the most problematic of pediat- ric cases. Planning the pediatric CT angiogram Determine that CT angiography is the appropriate examination In addition to CT angiography, considerations for thoracic cardiovascular structur al and functional assessment include echocardiography, MR angiogra- phy and venography, and conventional angiography. CT angiography is advantageous in that it provides a more global assessment of cardiovascular structures and adjacent structures, such as the lung and airway. The examination is also relatively quick to perform, with times that can approach 1 second given 64-slice technology. Sedation is rarely necessary compared with MR imaging and echocardiography, and the examination quality is more consistent (operator in- dependent). CT angiography is a relatively non- invasive procedure, compared with angiography. In addition, monitoring and direct observation of the patient are easier with CT angiography than with MR imaging. Contraindications for MR imaging vascular assessment including pacemakers and recent surgical procedures with some metallic materials are not present with CT a ngiography. Moreover, metal artifact is much less an issue with CT angiography than with MR angiography. For a more in-depth dis- cussion of the relative merits and disadvantages with CT angiography and MR angiography, the reader is referred to a recent series of reviews [5 –8]. There are disadvantages with CT angiography. CT angiography requires administration of intravenous (IV) contrast media. Adverse reactions, however, are singularly unusual in children. In addition, nephro- toxicity from contrast media in children is much less 0033-8389/05/$ – see front matter D 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.rcl.2004.09.013 radiologic.theclinics.com E-mail address: frush943@mc.duke.edu Radiol Clin N Am 43 (2005) 419 – 433 . nephro- toxicity from contrast media in children is much less 0 03 3-8 38 9/05/$ – see front matter D 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.rcl.2004.09.0 13 radiologic.theclinics.com E-mail. sternum. paterson306 Technique of Pediatric Thoracic CT Angiography Donald P. Frush, MD Division of Pediatric Radiology, Department of Radiology, Duke University Health System, 1905 McGovern-Davison. infant was managed conservatively. Fig. 3. (A) Type I congenital cystic adenomatoid malformation in a 12-month-old boy who presented with shortness of breath. Chest radiograph shows a hyperlucent

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