CT-guided localization of pulmonary nodules in children prior to video-assisted thoracoscopic surgical resection utilizing a combination of two previously described techniques.

BACKGROUND: Pulmonary nodules in pediatric oncology patients can present a diagnostic and treatment dilemma. Imaging findings are often nonspecific and tissue diagnosis may be required for appropriate treatment. The smaller subpleural nodules may not be visualized and cannot be palpated during video-assisted thoracoscopic surgical (VATS) resection. Preoperative localization has been beneficial in obtaining an adequate pathological specimen. OBJECTIVE: This study presents experience in a large pediatric hospital using CT-guided preoperative localization of pulmonary nodules combining two previously utilized techniques, hook wire and methylene blue blood patch localization. MATERIALS AND METHODS: A search of the electronic medical record utilizing a medical record search application was performed to identify all patients who underwent preoperative lung nodule localization during a 12.5-year period (July 1999 through January 2012). A retrospective chart review of these patients was then performed. Pre- and postoperative imaging, interventional radiology procedural images and reports, surgical reports, and pathology reports were obtained and evaluated. RESULTS: Thirty-five patients, with 40 nodules, who underwent preoperative CT-guided lung nodule localization were identified. Patients ranged in age from 8 months to 21 years. The pulmonary nodules ranged in size from 1.4 mm to 18 mm. Twelve nodules were localized using a Kopans breast lesion localization needle with hook wire, 4 were localized using a methylene blue blood patch, and 24 were localized using the combination of these two techniques. The technical success rate of all procedures was 100%. A pathological diagnosis was determined in 39 patients (97.5%). There were 6 (15.0%) minor complications and no major complications. CONCLUSION: CT-guided lung nodule localization using the combined techniques of methylene blue blood patch and hook wire is safe, technically feasible and successful in children. Using this combination of techniques will consistently yield a pathological diagnosis, is currently the preferred technique at our tertiary pediatric hospital and could be considered the new best practice.

Venous thrombosis and stenosis after peripherally inserted central catheter placement in children.

BACKGROUND: Peripherally inserted central catheters (PICCs) can lead to development of venous thrombosis and/or stenosis. The presence of venous thrombosis and/or stenosis may preclude children with chronic medical conditions from receiving lifesaving therapies, from hemodialysis in end-stage renal disease to total parenteral nutrition in short bowel syndrome. Several adult studies have found an association between PICCs and venous thrombosis and/or stenosis, but none has evaluated for this association in children. OBJECTIVE: To determine the incidence of venous thrombosis and/or stenosis after PICC placement and identify factors that increase the risk of venous thrombosis and/or stenosis after PICC placement in children. MATERIALS AND METHODS: We conducted a retrospective review of children ages 1-18 years with a PICC placed between January 2010 and July 2013 at our center, and included those who had at least one vascular imaging study of the ipsilateral extremity (Doppler ultrasound, venogram or MR angiogram) after PICC placement. Logistic regression was applied to determine risk factors for development of venous thrombosis and/or stenosis. RESULTS: One thousand, one hundred and ten upper extremity PICCs were placed, with 703 PICCs in the right and 407 PICCs in the left. Eight hundred fifty-one imaging studies (609 Doppler ultrasounds, 193 contrast venograms and 49 MR angiograms) were performed in 376 patients. The incidence of venous thrombosis and/or stenosis in the imaged cohort was 26.3%. PICC laterality, insertion site, duration, patient height to PICC diameter ratio, and number of PICCs per patient were not associated with development of venous thrombosis and/or stenosis. Additionally, primary diagnosis and symptoms at the time of imaging did not predict findings of venous thrombosis and/or stenosis. However, patients exposed to non-PICC central venous catheters (CVC) were more likely to develop venous thrombosis and/or stenosis (odds ratio 1.95, 1.10-3.45). CONCLUSION: More than a quarter of the vascular imaging studies performed in this study cohort showed previously unknown venous thrombosis and/or stenosis, irrespective of PICC laterality, insertion site, duration and size and the number of PICCs. A history of CVC was associated with a nearly two-fold increase in risk of venous thrombosis and/or stenosis after PICC placement. We suggest that PICCs and CVCs should be placed judiciously in all children, but especially in those with lifelong medical conditions who are more likely to incur direct consequences from limited vascular access.

Comparison of complications between pediatric peripherally inserted central catheter placement techniques.

BACKGROUND: Peripherally inserted central catheter (PICC) is among the most common procedures performed in children in the hospital setting. PICC insertion can be simplified with the use of a sheathed needle as an alternative to the modified Seldinger technique. OBJECTIVE: To retrospectively evaluate PICC placement for the technique used and the incidence of complications at a large pediatric tertiary care center. MATERIALS AND METHODS: We retrospectively reviewed all PICC placements at a single institution over a 4-year period. We reviewed patient records for demographic data, PICC placement technique, catheter size and number of lumens, and the incidence of complications (i.e. multiple attempted puncture sites, phlebitis and vessel thrombosis). We analyzed complication rates between two placement techniques using a chi-square test. RESULTS: We identified 8,816 successful PICC placements, 4,749 (53.9%) in males and 4,067 (46.1%) in females. The average age of the patients for which a line was placed was 5.6 years (range 1 day to 45 years). A direct sheathed needle puncture technique was used in 8,362 (94.9%) placements and a modified Seldinger technique was used in 454 (5.1%). Complications occurred in 312 (3.7%) of direct sheathed needle puncture placements versus 17 (3.7%) of modified Seldinger placements (P = 0.99). Multiple puncture sites were required in 175 (2.1%) attempted direct sheathed needle puncture placements compared with 8 (1.7%) attempted modified Seldinger placements (P = 0.63). Phlebitis occurred in 94 (1.1%) direct sheathed needle puncture lines versus 5 (1.1%) modified Seldinger placed lines (P = 0.96). Vessel thrombosis occurred in 43 (0.5%) direct sheathed needle puncture lines versus 4 (0.9%) modified Seldinger placed lines (P = 0.30). CONCLUSION: The direct peel-away sheathed needle vessel puncture technique and the modified Seldinger technique used to place PICC lines in children have similar complication rates.

Use of cone-beam CT and live 3-D needle guidance to facilitate percutaneous nephrostomy and nephrolithotripsy access in children and adolescents.

BACKGROUND: Gaining access into non-dilated renal collecting systems for percutaneous nephrolithotripsy, particularly in patients with prohibitive body habitus and/or scoliosis, is often challenging using conventional techniques. OBJECTIVE: To evaluate the feasibility of cone-beam CT for percutaneous nephrostomy placement for subsequent percutaneous nephrolithotripsy in children and adolescents. MATERIALS AND METHODS: A retrospective review of percutaneous nephrostomy revealed use of cone-beam CT and 3-D guidance in 12 percutaneous nephrostomy procedures for 9 patients between 2006 and 2015. All cone-beam CT-guided percutaneous nephrostomies were for pre-lithotripsy access and all 12 were placed in non-dilated collecting systems. RESULTS: Technical success was 100%. There were no complications. CONCLUSION: Cone-beam CT with 3-D guidance is a technically feasible technique for percutaneous nephrostomy in children and adolescents, specifically for nephrolithotripsy access in non-dilated collecting systems.

Comparison of pediatric radiation dose and vessel visibility on angiographic systems using piglets as a surrogate: antiscatter grid removal vs. lower detector air kerma settings with a grid - a preclinical investigation.

The purpose of this study was to reduce pediatric doses while maintaining or improv-ing image quality scores without removing the grid from X-ray beam. This study was approved by the Institutional Animal Care and Use Committee. Three piglets (5, 14, and 20 kg) were imaged using six different selectable detector air kerma (Kair) per frame values (100%, 70%, 50%, 35%, 25%, 17.5%) with and without the grid. Number of distal branches visualized with diagnostic confidence relative to the injected vessel defined image quality score. Five pediatric interventional radiologists evaluated all images. Image quality score and piglet Kair were statistically compared using analysis of variance and receiver operating curve analysis to define the preferred dose setting and use of grid for a visibility of 2nd and 3rd order vessel branches. Grid removal reduced both dose to subject and imaging quality by 26%. Third order branches could only be visualized with the grid present; 100% detector Kair was required for smallest pig, while 70% detector Kair was adequate for the two larger pigs. Second order branches could be visualized with grid at 17.5% detector Kair for all three pig sizes. Without the grid, 50%, 35%, and 35% detector Kair were required for smallest to largest pig, respectively. Grid removal reduces both dose and image quality score. Image quality scores can be maintained with less dose to subject with the grid in the beam as opposed to removed. Smaller anatomy requires more dose to the detector to achieve the same image quality score.

Communication in diagnostic radiology: meeting the challenges of complexity.

OBJECTIVE: As patients and information flow through the imaging process, value is added step-by-step when information is acquired, interpreted, and communicated back to the referring clinician. However, radiology information systems are often plagued with communication errors and delays. This article presents theories and recommends strategies to continuously improve communication in the complex environment of modern radiology. CONCLUSION: Communication theories, methods, and systems that have proven their effectiveness in other environments can serve as models for radiology.

Endovascular venous thrombolysis in children younger than 24 months.

PURPOSE: To evaluate the technical feasibility and safety of percutaneous endovascular thrombolysis for extremity deep venous thrombosis (DVT) in children < 24 months old. MATERIALS AND METHODS: A retrospective chart review of a clinical and imaging database was performed for pediatric patients who underwent endovascular therapy for DVT between January 2010 and July 2013. Indications, techniques, technical and clinical success, and complications were reviewed. Techniques for thrombolysis included catheter-directed therapy (CDT) using alteplase infusion via a multi-side hole catheter, mechanical thrombectomy, and angioplasty. Short-term outcomes were assessed using surgical and imaging follow-up examinations for patency of the targeted vessel. Patients included 11 children (mean age, 9 mo; range, 3 wk-23 mo) who consecutively underwent endovascular thrombolysis for upper extremity (n = 6) or lower extremity (n = 5) DVT. The most common indication was preservation of venous access for future cardiac surgery or medical therapy. RESULTS: The most common risk factor was the presence of a central venous catheter (10 of 11 patients). All patients with upper extremity DVT had congenital heart disease. CDT and angioplasty were performed in all patients. Venous patency was established in all patients. A grade III (95%-100%) thrombolysis response was achieved in seven patients, and a grade II (50%-95%) thrombolysis response was achieved in four patients. A major complication of pulmonary embolism occurred in one patient with upper extremity thrombolysis and was managed by intravenous systemic alteplase and heparin. No recurrence of thrombosis was found on average follow-up of 11.8 months (range, 1-41 mo). CONCLUSIONS: Percutaneous endovascular thrombolysis for extremity DVT is safe and technically feasible in children < 24 months old.

Ultrasound-guided interventions in children.

There are a variety of available imaging modalities used for minimally invasive procedures in children, however, among the most frequently used is ultrasound (US). The advantages of US are vast and include real-time visualization, lack of ionizing radiation, and all-around versatility. US is also inexpensive, portable and widely available. In general US guided procedures in children have applications in nearly every aspect of medical therapy. Properly trained practitioners with US imaging experience and detailed knowledge of the relevant anatomy provide an invaluable service to the care of pediatric patients in many centers. This paper will discuss many of the image guided procedures that are performed in children and offer practical techniques from the collective experience of our practice at a large pediatric tertiary care center.

Clinically useful dilution factors for iodine and gadolinium contrast material: an animal model of pediatric digital subtraction angiography using state-of-the-art flat-panel detectors.

BACKGROUND: Iodinated and gadolinium contrast agents pose some risk for certain pediatric patients, including allergic-like reactions, contrast-induced nephropathy (CIN) and nephrogenic systemic fibrosis (NSF). Digital flat-panel detectors enhance image quality during angiography and might allow use of more dilute contrast material to decrease risk of complications that might be dose-dependent, such as CIN and NSF. OBJECTIVE: To assess the maximum dilution factors for iodine- and gadolinium-based contrast agents suitable for vascular imaging with fluoroscopy and digital subtraction angiography (DSA) on digital flat-panel detectors in an animal model. MATERIALS AND METHODS: We performed selective catheterization of the abdominal aorta, renal artery and common carotid artery on a rabbit. In each vessel we performed fluoroscopy and DSA during contrast material injection using iodinated and gadolinium contrast material at 100%, 80%, 50%, 33% and 20% dilutions. An image quality score (0 to 3) was assigned by each of eight evaluators. Intracorrelation coefficient, paired t-test, one-way repeated analysis of variance, Spearman correlation and receiver operating characteristic curve analysis were applied to the data. RESULTS: Overall the image quality scores correlated linearly with dilution levels. For iodinated contrast material, the optimum cut-off level for DSA when a score of at least 2 is acceptable is above 33%; it is above 50% when a score of 3 is necessary. For gadolinium contrast material, the optimum cut-off for DSA images is above 50% when a score of at least 2 is acceptable and above 80% when a score of 3 is necessary. CONCLUSION: Knowledge of the relationship between image quality and contrast material dilution might allow a decrease in overall contrast load while maintaining appropriate image quality when using digital flat-panel detectors.

Inferior vena cava filters in children: our experience and suggested guidelines.

Although use of inferior vena cava (IVC) filters for prophylaxis against pulmonary embolism (PE) is well reported in adults, long-term studies in children are lacking. We performed retrospective review of imaging and clinical database of IVC filters for the last 12 years. Thirty-five patients (mean age: 15.5 y) underwent filter placement and/or retrieval. Indications for placement were contraindication to anticoagulation with known deep venous thrombosis (DVT) (18) or high risk of venous thromboembolism (5), recurrent DVT despite anticoagulation (1), and prophylaxis before endovascular thrombolysis (8). All filter placements were technically successful without any complications. Filter retrieval was successful in 15 of 19 attempted (79%) at a mean of 42 days. Two complications occurred during retrieval: IVC stenosis successfully treated with angioplasty and contained IVC perforation. Endothelialization of filter prevented retrieval in 4 patients. Mean follow-up was 29.3 months. No patients had IVC thrombosis, breakthrough pulmonary embolism, filter fracture, or embolism. Two patients had recurrent DVT. Our results indicate that IVC filters can be successfully placed and retrieved in children with minimal procedural complications; follow-up demonstrates acceptable complication rate owing to presence of filters. Prophylactic IVC filter placement may be considered before endovascular thrombolysis for lower extremity DVT. Retrievable filters should be used in children for appropriate indications.

Use of an Amplatz dilator to facilitate transrectal abscess drainage in children.

Image-guided transrectal drainage is an effective treatment option for many deep pelvic abscesses in children. Currently, a variety of imaging and catheter techniques are used to access and drain these abscesses. The present report describes an approach for introducing the transrectal catheter by using transabdominal ultrasound guidance to direct transrectal advancement of an Amplatz dilator with coaxial placement of the metal cannula and inner trocar from a pigtail catheter set, followed by placement of the pigtail catheter via Seldinger technique. This approach eliminates some of the limitations of other transrectal techniques. The present report describes a single-institutional experience with this technique in 13 patients.

Creating a comprehensive customer service program to help convey critical and acute results of radiology studies.

OBJECTIVE: Communication of acute or critical results between the radiology department and referring clinicians has been a deficiency of many radiology departments. The failure to perform or document these communications can lead to poor patient care, patient safety issues, medical-legal issues, and complaints from referring clinicians. To mitigate these factors, a communication and documentation tool was created and incorporated into our departmental customer service program. This article will describe the implementation of a comprehensive customer service program in a hospital-based radiology department. MATERIALS AND METHODS: A comprehensive customer service program was created in the radiology department. Customer service representatives were hired to answer the telephone calls to the radiology reading rooms and to help convey radiology results. The radiologists, referring clinicians, and customer service representatives were then linked via a novel workflow management system. This workflow management system provided tools to help facilitate the communication needs of each group. The number of studies with results conveyed was recorded from the implementation of the workflow management system. RESULTS: Between the implementation of the workflow management system on August 1, 2005, and June 1, 2009, 116,844 radiology results were conveyed to the referring clinicians and documented in the system. This accounts for more than 14% of the 828,516 radiology cases performed in this time frame. CONCLUSION: We have been successful in creating a comprehensive customer service program to convey and document communication of radiology results. This program has been widely used by the ordering clinicians as well as radiologists since its inception.

Teleradiology 2010: technical and organizational issues.

In the United States, teleradiology using an external service to provide preliminary or final medical image interpretation is an increasingly necessary component of radiology services, especially for smaller institutions or practices. This review aims to provide a background history to the current teleradiology services provided and also addresses the limitations and issues involved in organising such a service.

IR challenges in the MSK system.

As the capability of medical imaging equipment improves, and relatively new modalities such as cone beam CT with guidance becomes more widely available, the range and complexity of image guided orthopedic procedures continues to expand. Challenges include the predictable technical and anatomic issues, as well as the complex operational and political issues associated with moving and integrating an interventional radiology service into the traditional operating room environment.

Image Gently: providing practical educational tools and advocacy to accelerate radiation protection for children worldwide.

The Alliance for Radiation Safety in Pediatric Imaging is an organization of over 45 international professional societies and agencies with the goal of promoting radiation safety for children. The Alliance, through the Image Gently campaign, uses social marketing techniques and critical partnerships with vendors, government agencies, and not-for-profit organizations, to advocate best practices in radiation use and safety. Advocacies include improving education regarding radiation risk to patients from medical imaging for radiologists, technologists, and referring physicians; promoting standardization of dose measurements and display across vendor equipment; and improving medical literacy for parents.

Exchange of an occluded nasojejunal tube facilitated by angioplasty balloon-induced rupture.

We describe a method of exchanging a blocked nasojejunal (NJ) tube involving the use of a percutaneous transluminal angioplasty balloon to rupture the tube, followed by insertion of a guidewire through this rupture to create a guide for subsequent placement of a modified NJ tube. We used this technique in a child with a critical need for an NJ tube, in whom routine guidewire exchange was not feasible because of tube obstruction as well as the patient's anatomic abnormalities. This technique might also be useful for other patients in whom standard techniques are ineffective.

Image Gently(SM): a national education and communication campaign in radiology using the science of social marketing.

Communication campaigns are an accepted method for altering societal attitudes, increasing knowledge, and achieving social and behavioral change particularly within public health and the social sciences. The Image Gently(SM) campaign is a national education and awareness campaign in radiology designed to promote the need for and opportunities to decrease radiation to children when CT scans are indicated. In this article, the relatively new science of social marketing is reviewed and the theoretical basis for an effective communication campaign in radiology is discussed. Communication strategies are considered and the type of outcomes that should be measured are reviewed. This methodology has demonstrated that simple, straightforward safety messages on radiation protection targeted to medical professionals throughout the radiology community, utilizing multiple media, can affect awareness potentially leading to change in practice.