Dimitri A. Parra

Imaging of Ambiguous Genitalia: Classification and Diagnostic Approach

Disorders of sex development (DSDs) are congenital conditions in which the development of chromosomal, gonadal, or anatomic sex is atypical. DSDs can be classified broadly into four categories on the basis of gonadal histologic features: female pseudohermaphroditism (46,XX with two ovaries); male pseudohermaphroditism (46,XY with two testes); true hermaphroditism (ovotesticular DSD) (both ovarian and testicular tissues); and gonadal dysgenesis, either mixed (a testis and a streak gonad) or pure (bilateral streak gonads). Imaging plays an important role in demonstrating the anatomy and associated anomalies. Ultrasonography is the primary modality for demonstrating internal organs; genitography is used to assess the urethra, vagina, and any fistulas or complex tracts; and magnetic resonance imaging is used as an adjunct modality to assess for internal gonads and genitalia. Early and appropriate gender assignment is necessary for healthy physical and psychologic development of children with ambiguous genitalia. Gender assignment can be facilitated with a team approach that involves a pediatric endocrinologist, geneticist, urologist, psychiatrist, social worker, neonatologist, nurse, and radiologist, allowing timely diagnosis and proper management.

Normal Doppler Spectral Waveforms of Major Pediatric Vessels: Specific Patterns

Every major vessel in the human body has a characteristic flow pattern that is visible in spectral waveforms obtained in that vessel with Doppler ultrasonography (US). Spectral waveforms reflect the physiologic status of the organ supplied by the vessel, as well as the anatomic location of the vessel in relation to the heart. In addition, the waveforms may be affected by age- and development-related hemodynamic differences. For example, adults tend to have higher flow velocities, whereas neonates, particularly those born prematurely, have higher resistance to flow, especially in the cerebral and renal vascular beds. As Doppler US is performed with increasing frequency for vascular evaluation in children, the recognition of normal flow patterns has become imperative. Familiarity with the waveforms characteristic of specific veins and arteries in children is important. In addition, an understanding of the hemodynamic factors involved provides a useful basis for interpreting waveform abnormalities.

Increased complexity and complications associated with multiple peripherally inserted central catheter insertions in children: the tip of the iceberg.

PURPOSE To assess the effects of repeated placements of peripherally inserted central catheters (PICCs) on the venous system in children. MATERIALS AND METHODS Children who underwent successful first-time PICC placements between 2005 and 2007 were retrospectively evaluated. Patient demographics, procedural data, and complications were obtained from hospital databases. Data from subsequent PICC insertions were compared with those from previous PICC insertions. A generalized estimating equation was used with appropriate statistical tests for data analysis. RESULTS PICCs were grouped into four groups: first PICCs (n = 1,274), second PICCs (n = 167), third PICCs (n = 52), and fourth to seventh PICCs (n = 32). Successive PICCs were associated with progressively increased difficulty of access compared with earlier PICCs, as demonstrated by significant increases in procedural duration (P = .01) and fluoroscopy time (P = .005). Increased complexity was also evident through significant increases in the percentages of cases that required venography/digital subtraction angiography (P <.0001), multiple attempts to gain venous access (P <.0001), and a switch to another limb for venous access (P <.0001) between subsequent and first PICCs. In addition, rates of procedural complications also increased for subsequent PICCs compared with first PICCs (P <.0001). Furthermore use of the most preferred vein for vascular access significantly decreased in subsequent versus first PICC insertions (P <.0001). CONCLUSIONS Increased procedural complexity and complications were found with successive PICC insertions. These results confirm the need for a prospective study to directly assess the long-term effects of PICCs on venous patency.

Sonographic diagnosis of intestinal polyps in children.

Although colonoscopy is the modality of choice for the diagnosis of intestinal polyps, sonography may be the first diagnostic modality in the evaluation of children with this pathology. Graded compression sonography of the small and large bowel may be useful in diagnosing intestinal polyps. A specific diagnosis is possible in many cases as most polyps have a characteristic appearance. Although sonography is not intended to replace endoscopy in the diagnostic work-up of intestinal polyps, it is important for radiologists to be aware of this appearance as they can be the first in making the diagnosis of intestinal polyps using sonography.

Are Cuffed Peripherally Inserted Central Catheters Superior to Uncuffed Peripherally Inserted Central Catheters? A Retrospective Review in a Tertiary Pediatric Center

PURPOSE To assess the use of cuffed peripherally inserted central catheters (PICCs) compared with uncuffed PICCs in children with respect to their ability to provide access until the end of therapy. MATERIALS AND METHODS A retrospective review of PICCs inserted between January 2007 and December 2008 was conducted. Data collected from electronic records included patient age, referring service, clinical diagnosis, inserting team (pediatric interventional radiologists or neonatal intensive care unit [NICU] nurse-led PICC team), insertion site, dates of insertion and removal, reasons for removal, and need for a new catheter insertion. A separate subset analysis of the NICU population was performed. Primary outcome measured was the ability of the PICCs to provide access until the end of therapy. RESULTS Cuffed PICCs (n = 1,201) were significantly more likely to provide access until the end of therapy than uncuffed PICCs (n = 303) (P = .0002). Catheter removal before reaching the end of therapy with requirement of placement of a new PICC occurred in 26% (n = 311) of cuffed PICCs and 38% (n = 114) of uncuffed PICCs. Uncuffed PICCs had a significantly higher incidence of infections per 1,000 catheter days (P = .023), malposition (P = .023), and thrombus formation (P = .022). In the NICU subset analysis, cuffed PICCs had a higher chance of reaching end of therapy, but this was not statistically significant. CONCLUSIONS In this pediatric population, cuffed PICCs were more likely to provide access until the end of therapy. Cuffed PICCs were associated with lower rates of catheter infection, malposition, and thrombosis than uncuffed PICCs.

Successful use of indwelling tunneled catheters for the management of effusions in children with advanced cancer

Malignant pleural effusion (MPE) and ascites (MA) negatively impact quality of life of palliative patients. Treatment options are limited. This studys purpose is to examine the experience with indwelling tunneled catheters (ITCs) for management of MPE/MA in children with advanced cancer.

Computed Tomography Angiography in Acute Gastrointestinal and Intra-abdominal Bleeding in Children: Preliminary Experience

Acute gastrointestinal (GI) and intra-abdominal bleeding from different etiologies is a medical emergency with a significant morbidity and mortality. Fast detection and localization of the bleeding site are essential for effective hemostatic therapy [1]. In children with a GI bleed, it is important to assess the hemodynamic status and to establish the site of bleeding and a differential diagnosis according to the presentation and the age of the patient [2]. In trauma, a prompt diagnosis of a bleeding site can improve the efficacy of patient management [3]. Rupture and bleeding are a known presentation of solid tumours, including hepatoblastoma and hepatocellular carcinoma [4]. The most frequent causes of GI and intra-abdominal bleeding in children are shown in Table 1. The initial approach to a patient with GI bleed is endoscopy, which can be diagnostic and therapeutic. If it fails, then catheter angiography is considered. With trauma or tumoural bleeding, angiography is considered according to the diagnostic imaging workup and clinical picture. Pediatric angiography has recognized complications, which nowadays are less frequent due to the improvement in the equipment and the use of ultrasound (US) for vascular access [5]. In taking this into consideration, it is important to adequately select the group of patients that will benefit from a conventional catheter angiography in this particular clinical setting. Computed tomography angiography (CTA) has an emerging role in the diagnosis of acute GI bleed in adults. Its

Technique, Safety, and Yield of Bone Biopsies for Histomorphometry in Children

PURPOSE To evaluate image-guided bone biopsy for bone histomorphometry to assess osteoporosis in children with respect to safety and yield. MATERIALS AND METHODS A single-center retrospective review was performed of 79 bone biopsies in 73 patients performed between 2007 and 2015. Biopsies of the iliac bone were performed under general anesthesia, after tetracycline labeling, using a Rochester needle (Medical Innovations International, Inc, Rochester, Minnesota). Ultrasound and fluoroscopic guidance were used in all procedures. Biopsy technique, technical success, safety, and histomorphometry results (complete, incomplete, none) were analyzed. RESULTS There were 41 male patients (51.8%). Technical success was achieved in 76/79 (96%) procedures. Of 79 biopsies, 75 (95%) were uneventful. Unplanned overnight observation was required in 3 (minor SIR grade B), and prolonged hospital stay owing to hematoma causing nerve compression pain was required in 1 (major SIR grade D). Complete histomorphometric reports were obtained in 69 (87%) procedures, incomplete reports were obtained in 7 (9%), and no reports were obtained in 3(4%). Incomplete reports were insufficient to provide a definitive diagnosis or guide treatment. Histomorphometry impacted subsequent therapy in 69 (87%) biopsies. CONCLUSIONS Image-guided bone biopsy for osteoporosis using the Rochester needle is a valuable and safe technique for establishing the diagnosis of osteoporosis and directing treatment based on histomorphometry results.

Technical tips to perform safe and effective Ultrasound Guided steroid joint injections in children

BackgroundThe aim of this article is to describe the technique used to perform ultrasound guided steroid joint injections in children in a group of joints that can be injected using ultrasound as the only image guidance modality.FindingsThe technique is described and didactic figures are provided to illustrate key technical concepts.ConclusionIt is very important to be familiar with the sonographic appearance of the pediatric joints and the developing bone when performing ultrasound-guided joint injections in children.

Gastrointestinal Interventions in Children

Gastrointestinal (GI) interventions comprise a large component of nonvascular interventions in children. This chapter includes the most common pediatric GI interventions: balloon dilatation and enterostomy access.