Unenhanced MRI of the Abdomen and Pelvis in the Comprehensive Evaluation of Acute Atraumatic Abdominal Pain in Children.

OBJECTIVE. The purpose of this study is to show the utility of rapid unenhanced MRI in the comprehensive assessment of acute atraumatic abdominal pain in children, including appendicitis and alternate diagnoses, and to review the MRI features of common acute abdominal and pelvic conditions in a large, single-institution cohort. CONCLUSION. Rapid unenhanced MRI is an excellent option for the initial, comprehensive evaluation of acute abdominal emergencies in pediatric patients because it can diagnose the full range of presenting abnormalities, including causes of abdominal pain warranting surgical and nonsurgical management.

Unique Case of Congenital Duodenal Atresia and a Choledochal Cyst and the Hypothesis of Their Embryological Evolution.

The concomitant occurrence of duodenal atresia (DA) and a choledochal cyst (CC) has rarely been reported. Knowledge of both the presentation and management of this rare co-occurrence is imperative in avoiding potential complications and sequelae, such as biliary metaplasia. Herein we describe a female infant born at 32 weeks gestational age who was diagnosed with duodenal atresia and annular pancreas postnatally, who had subsequent findings of malrotation and a choledochal cyst, as seen from contrast imaging. Uncomplicated repair of the DA and obstruction was performed at 4 days of life. She re-presented 2 years later with non-bloody, nonbilious emesis and was found to have elevated amylase, lipase and liver enzymes. Imaging revealed dilated intra-hepatic ducts, a distended gallbladder and a large choledochal cyst. She underwent a cholecystostomy tube placement followed by a definitive choledochal cyst excision with immediate improvement following surgery and full resolution of symptoms before discharge.

First-Line Diagnostic Evaluation with MRI of Children Suspected of Having Acute Appendicitis.

Background Advances in abdominal MRI have enabled rapid, free-breathing imaging without the need for intravenous or oral contrast material. The use of MRI as the primary imaging modality for suspected appendicitis has not been previously studied. Purpose To determine the diagnostic performance of MRI as the initial imaging modality in children suspected of having acute appendicitis. Materials and Methods The study included consecutive patients 18 years of age and younger presenting with acute abdominal pain at a tertiary care institution from January 2013 through June 2016 who subsequently underwent an unenhanced MRI examination as the primary diagnostic imaging modality. Electronic medical records and radiology reports were retrospectively evaluated for the feasibility and diagnostic performance of MRI, with surgical pathology and follow-up electronic records as reference standards. Statistical analyses were performed by using simple binomial proportions to quantify sensitivity, specificity, and accuracy, and exact 95% confidence intervals (CIs) were obtained. Results After exclusions, 402 patients (median age: 13 years; interquartile range [IQR], 9-15 years; 235 female patients; 167 male patients) were included. Sedation for MRI was required in 13 of 402 patients (3.2%; 95% CI: 1.7%, 5.5%). The appendix was visualized in 349 of 402 patients (86.8%; 95% CI: 83.1%, 90%); for the remaining patients, a diagnosis was provided on the basis of secondary signs of appendicitis. The sensitivity, specificity, and accuracy of MRI as the primary diagnostic imaging modality for the evaluation of acute appendicitis were 97.9% (95 of 97; 95% CI: 92.8%, 99.8%), 99% (302 of 305; 95% CI: 97.2%, 99.8%), and 98.8% (397 of 402; 97.1%, 99.6%), respectively. Among patients with negative findings for appendicitis at MRI, an alternate diagnosis was provided in 113 of 304 patients (37.2%; 95% CI: 31.7%, 42.9%). Conclusion When performed as the initial imaging modality in children suspected of having acute appendicitis, MRI examinations had high diagnostic performance for the diagnosis of acute appendicitis and in providing alternative diagnoses. © RSNA, 2019 See also the editorial by Dillman and Trout in this issue.

Pediatric interventional radiology workforce survey: 10-year follow-up.

BACKGROUND: Pediatric interventional radiology is a distinct subspecialty differing from both pediatric diagnostic radiology and adult interventional radiology. We conducted a workforce survey in 2005 to evaluate the state of pediatric interventional radiology at that time. Since then there have been many advancements to the subspecialty, including the founding of the Society for Pediatric Interventional Radiology (SPIR). OBJECTIVE: To evaluate the current state of the pediatric interventional radiology workforce and compare findings with those of the initial 2005 workforce survey. MATERIALS AND METHODS: We sent a two-part survey electronically to members of SPIR, the Society for Pediatric Radiology (SPR), the Society of Chairmen of Radiology in Children's Hospitals (SCORCH) and the Society of Interventional Radiology (SIR). Part 1 focused on individual practitioners (n=177), while part 2 focused on group practices and was answered by a leader from each group (n=88). We examined descriptive statistics and, when possible, compared the results to the study from 2005. RESULTS: A total of 177 individuals replied (a 331% increase over the first study) and 88 pediatric interventional radiology (IR) service sites responded (a 131.6% increase). Pediatric IR has become a more clinically oriented specialty, with a statistically significant increase in services with admitting privileges, clinics and performance of daily rounds. Pediatric IR remains diverse in training and practice. Many challenges still exist, including anesthesia/hospital support, and the unknown impact of the new IR residency on pediatric IR training, although the workforce shortage has been somewhat alleviated, as demonstrated by the decreased mean call from 165 days/year to 67.2 days/year. CONCLUSION: Pediatric interventional radiology practitioners and services have grown significantly since 2005, although the profile of this small subspecialty has changed and some challenges remain.

Thoracoscopic decortication vs tube thoracostomy with fibrinolysis for empyema in children: a prospective, randomized trial.

PURPOSE: Management of empyema has been debated in the literature for decades. Although both primary video-assisted thoracoscopic surgery (VATS) and tube thoracostomy with pleural instillation of fibrinolytics have been shown to result in early resolution when compared to tube thoracostomy alone, there is a lack of comparative data between these modes of management. Therefore, we conducted a prospective, randomized trial comparing VATS to fibrinolytic therapy in children with empyema. METHODS: After Institutional Review Board approval, children defined as having empyema by either loculation on imaging or more than 10,000 white blood cells/microL were treated with VATS or fibrinolysis. Based on our retrospective data using length of postoperative hospitalization as the primary end point, a sample size of 36 patients was calculated for an alpha of .5 and a power of 0.8. Fibrinolysis consisted of inserting a 12F chest tube followed by infusion of 4 mg tissue plasminogen activator mixed with 40 mL of normal saline at the time of tube placement followed by 2 subsequent doses 24 hours apart. RESULTS: At diagnosis, there were no differences between groups in age, weight, degree of oxygen support, white blood cell count, or days of symptoms. The outcome data showed no difference in days of hospitalization after intervention, days of oxygen requirement, days until afebrile, or analgesic requirements. Video-assisted thoracoscopic surgery was associated with significantly higher charges. Three patients (16.6%) in the fibrinolysis group subsequently required VATS for definitive therapy. Two patients in the VATS group required ventilator support after therapy, one of whom required temporary dialysis. No patient in the fibrinolysis group clinically worsened after initiation of therapy. CONCLUSIONS: There are no therapeutic or recovery advantages between VATS and fibrinolysis for the treatment of empyema; however, VATS resulted in significantly greater charges. Fibrinolysis may pose less risk of acute clinical deterioration and should be the first-line therapy for children with empyema.

Successful percutaneous drainage of duodenal hematoma after blunt trauma.

Duodenal hematoma after blunt trauma is usually treated nonoperatively with bowel rest, nasogastric tube suction, and intravenous hydration. We report a case in which obstructive symptoms persisted despite more than 2 weeks of conservative management. An ultrasound-guided percutaneous drain was placed, with successful resolution of symptoms.

Presumed appendiceal abscess discovered to be ruptured Meckel diverticulum following percutaneous drainage.

A Meckel diverticulum is an embryonic remnant of the omphalomesenteric duct that occurs in approximately 2% of the population. Most are asymptomatic; however, they are vulnerable to inflammation with subsequent consequences including diverticulitis and perforation. We report an 11-year-old boy who underwent laparoscopic appendectomy for perforated appendicitis at an outside institution. During his convalescence he underwent percutaneous drainage of a presumed postoperative abscess. A follow-up drain study demonstrated an enteric fistula. The drain was slowly removed from the abdomen over a period of 1 week. Three weeks following drain removal the patient reported recurrent nausea and abdominal pain. A CT scan demonstrated a 3.7-cm rim-enhancing air-fluid level with dependent contrast consistent with persistent enteric fistula and abscess. Exploratory laparoscopy was performed, at which time a Meckel diverticulum was identified and resected. This case highlights the diagnostic challenge and limitations of conventional radiology in complicated Meckel diverticulum.

Percutaneous biopsy of head and neck lesions with CT guidance: various approaches and relevant anatomic and technical considerations.

Deep-seated head and neck lesions, which traditionally were evaluated by surgical means, are now accessible with less invasive computed tomography-guided percutaneous needle biopsy techniques. Major vessels, the trachea, and osseous structures like the maxilla, mandible, and vertebrae often preclude direct access to these lesions. It is important to understand the anatomy relevant to safe access route planning and the techniques, advantages, and limitations associated with various approaches used for percutaneous biopsy of head and neck lesions. For biopsy of suprahyoid head and neck lesions, including those of the skull base and upper cervical vertebrae, various approaches such as the subzygomatic, retromandibular, paramaxillary, submastoid, transoral, and posterior approaches can be used. Lesions in the infrahyoid portion of the neck and lower cervical vertebrae can be accessed with the anterolateral approach (between the airways and the carotid sheath), posterolateral approach (posterior to the carotid sheath), and direct posterior approach. The location and extent of the lesions and their relationship to adjacent structures influence the choice of the trajectory to use. Careful planning of the procedure and considerable familiarity with head and neck anatomy are necessary for a biopsy that is both precise and safe.

Application of transcranial Doppler sonography in children with acute neurologic events due to primary cerebral and West Nile vasculitis.

We describe the use of serial transcranial Doppler studies to evaluate neurovascular disease in three girls presenting with acute stroke due to primary cerebral vasculitis (n = 2) and West Nile vasculitis (n = 1). Correlation of abnormal findings on transcranial Doppler sonography was compared with those of MR angiography and conventional angiography in each child. All three girls had left middle cerebral artery infarcts on MR imaging, with an abnormal left middle cerebral artery detected by MR angiography, conventional angiography, and transcranial Doppler sonography in each child. In all three cases, findings of the transcranial Doppler sonography, MR imaging, and catheter angiography were concordant.

Imaging-guided percutaneous biopsy of mediastinal lesions: different approaches and anatomic considerations.

Percutaneous needle biopsy with imaging guidance allows access to lesions in virtually all mediastinal locations. A direct mediastinal approach, which enables extrapleural needle placement, is the preferred method to avoid the risk of pneumothorax. Techniques that allow extrapleural access include the parasternal, paravertebral, transsternal, and suprasternal approaches, which are performed with computed tomographic or ultrasonographic guidance. The parasternal approach is used for biopsy of anterior or middle mediastinal lesions when the lesion or intervening mediastinal fat extends to the anterior chest wall, lateral to the sternum; injury to the internal mammary vessels is a potential complication. The paravertebral approach is used for biopsy of subcarinal and other posterior mediastinal lesions; saline solution is often injected to widen the mediastinum. The transsternal approach, which involves needle placement through the sternum, is used for biopsy of anterior or middle mediastinal lesions that are not accessible with the parasternal approach. Biopsy of superior mediastinal lesions can be performed with a suprasternal approach. An alternative to these direct mediastinal approaches involves advancing the needle through a pleural space created by an existing pleural effusion or iatrogenic pneumothorax. Another alternative is the transpulmonary approach, which involves transgression of the lung and visceral pleura by the needle and is associated with a substantial risk of pneumothorax.

New suction guide needle designed to reduce the incidence of biopsy-related pneumothorax: experimental evaluation in canine model.

In an attempt to remove air that enters the pleural space during computed tomography (CT)-guided coaxial transthoracic needle biopsy, the authors fashioned an 18-gauge experimental suction guide needle and evaluated the incidence of pneumothorax with this needle in comparison to the incidence of pneumothorax with a standard 18-gauge guide needle in a canine model. This experiment had animal care and use committee approval. Ten dogs underwent a biopsy of each lung, for a total of 20 lung biopsies. Half of the biopsies were performed by using the experimental needle (five right lungs, five left lungs), and half were performed by using a standard guide needle. CT revealed pneumothorax during the procedure and was performed to reveal pneumothorax 1 and 3 hours after the procedure. A significant reduction (P < .016) in intraprocedural lung biopsy-associated pneumothorax was found when the experimental guide needle was used.

Transhepatic ipsilateral right portal vein embolization extended to segment IV: improving hypertrophy and resection outcomes with spherical particles and coils.

PURPOSE: To analyze outcomes after right portal vein embolization extended to segment IV (right PVE + IV) before extended right hepatectomy, including liver hypertrophy, resection rates, and complications after embolization and resection, and to assess differences in outcomes with two different particulate embolic agents. MATERIALS AND METHODS: Between 1998 and 2004, transhepatic ipsilateral right PVE + IV with particles and coils was performed in 44 patients with malignant hepatobiliary disease, including metastases (n = 24), biliary cancer (n = 14), and hepatocellular carcinoma (n = 6). Right PVE + IV was considered if the future liver remnant (FLR; segments II/III with or without I) was less than 25% of the total estimated liver volume (TELV). Tris-acryl microspheres (100-700 microm; n = 21) or polyvinyl alcohol (PVA) particles (355-1,000 microm; n = 23) were administered in a stepwise fashion. Smaller particles were used to occlude distal branches, followed by larger particles to occlude proximal branches until near-complete stasis. Coils were then placed in secondary portal branches. Computed tomographic volumetry was performed before and 3-4 weeks after right PVE + IV to assess FLR hypertrophy. Liver volumes and postembolization and postoperative outcomes were measured. RESULTS: After right PVE + IV with PVA particles, FLR volume increased 45.5% +/- 40.9% and FLR/TELV ratio increased 6.9% +/- 5.6%. After right PVE + IV with tris-acryl microspheres, FLR volume increased 69.0% +/- 30.7% and FLR/TELV ratio increased 9.7% +/- 3.3%. Differences in FLR volume (P = .0011), FLR/TELV ratio (P = .027), and resection rates (P = .02) were statistically significant. Seventy-one percent of patients underwent extended right hepatectomy (86% after receiving tris-acryl microspheres, 57% after receiving PVA). Thirteen patients (29%) did not undergo resection (extrahepatic spread [n = 9], inadequate hypertrophy [n = 3], other reasons [n = 1]). No patient developed postembolization syndrome or progressive liver insufficiency after embolization or resection. One death after resection occurred as a result of sepsis and hemorrhage. Median hospital stays were 1 day after right PVE + IV and 7 days after resection. CONCLUSION: Transhepatic ipsilateral right PVE + IV with use of particles and coils is a safe, effective method for inducing contralateral hypertrophy before extended right hepatectomy. Embolization with small spherical particles provides improved hypertrophy and resection rates compared with larger, nonspherical particles.

Small (

PURPOSE: To retrospectively compare the diagnostic yield and complications associated with the use of short versus long needle paths for computed tomography (CT)-guided biopsy of small subpleural lung lesions. MATERIALS AND METHODS: The study was approved by the institutional review board, and the requirement for informed patient consent was waived. The medical and imaging records of patients who underwent CT-guided biopsy of subpleural pulmonary nodules measuring up to 2 cm in diameter were reviewed. The study included 176 patients (79 men, 97 women; age range, 18-84 years) who were divided into two groups: In group A, a direct approach in which the needle traversed a short lung segment was used. In group B, an indirect approach involving the use of a longer needle path was used. Diagnostic yield, accuracy, and pneumothorax and chest tube placement rates were compared between the two groups. Two-tailed t tests and Pearson chi(2) tests were used to analyze continuous and categorized variables, respectively. RESULTS: Group A comprised 48 patients; and group B, 128 patients. The mean needle path length was 0.4 cm in group A and 5.6 cm in group B. The short-path approach necessitated more needle punctures (mean, 2.9 vs 1.8 with long-path approach, P < .001) through the pleura. The diagnostic yield in group A was significantly lower than that in group B (71% vs 94%, P < .001), particularly in patients with small (0-1-cm) nodules (40% in group A vs 94% in group B, P < .001). The frequency of postbiopsy pneumothorax was identical (69%) in the two groups. However, more group B than group A patients required chest tube placement for treatment of pneumothorax (38% vs 17%, P = .006). CONCLUSION: Use of long-needle-path biopsy of subpleural lesions resulted in a higher diagnostic yield, especially for small nodules. However, compared with the short-needle-path technique, this approach was associated with a higher frequency of chest tube placement for pneumothorax.

Percutaneous ultrasound-guided biopsy in the definitive diagnosis of osteosarcoma.

Thirty-three patients with 35 bone lesions suspicious for osteosarcoma underwent image-guided biopsy. Of those 35 biopsies, 12 were performed with use of fluoroscopy or computed tomography (CT) guidance to target the osseous abnormality. Diagnostic magnetic resonance imaging revealed a soft tissue component in 23 cases; in these cases, biopsies were performed with use of ultrasonography (US) to target the soft tissue component of the tumor. Of the 35 tumors in which biopsy was performed, 33 (94%) were definitively diagnosed as osteosarcoma by image-guided biopsy. All 23 US-guided biopsies resulted in definitive diagnosis. Two of the 12 fluoroscopy- or CT-guided biopsies (17%) were inconclusive.

Fistulas of the lower urinary tract: percutaneous approaches for the management of a difficult clinical entity.

Fistulas of the lower urinary tract are uncommon conditions that may occur spontaneously or after therapy in patients with various pelvic abnormalities. When present, these fistulas are associated with urine leakage, which is often socially distressing and disabling. Unfortunately, factors that lead to the formation of genitourinary fistulas often increase their complexity or preclude surgical repair. A high failure rate is associated with surgical repair, and many patients are not optimal surgical candidates. For such patients, a percutaneous treatment approach is highly desirable. Percutaneous ureteral occlusion combined with insertion of a functioning nephrostomy tube allows complete diversion of urine in those patients in whom nephrostomy alone does not provide adequate relief. Many approaches to percutaneous ureteral occlusion have been used with variable success, including coils and gelatin sponge, isobutyl-2-cyanoacrylate, detachable balloons, radiofrequency electrocautery, ureteral clipping, and solid and soft polymer agents. Furthermore, percutaneous or retrograde ureteral stents may be used to preserve antegrade urine flow, and surgical options are also available. It is essential that the interventional radiologist involved in the care of these patients be familiar with these different techniques as well as with the limitations, pitfalls, and possible complications of their use.

Use of inferior vena caval filters and survival in patients with malignancy.

BACKGROUND: Inferior vena cava (IVC) filters have proven to be a viable alternative to anticoagulation therapy for the prevention of life-threatening pulmonary emboli (PE) for patients who have contraindications to anticoagulation therapy. The clinical benefit of placing IVC filters in patients with advanced-stage cancer is controversial. The current study reported the authors' experience with IVC filters in patients with cancer. METHODS: Between January 2000 and May 2003, IVC filters were placed in 308 patients with venous thromboembolic (VTE) disease. Of these patients, 267 had solid tumors and 41 had liquid tumors. Outcome was reviewed retrospectively with regards to patient survival as well as procedural and filter-related complications. Patients with solid and liquid tumors were used to generate Kaplan-Meier estimates for survival and the probability of surviving 30, 90, and 365 days was also calculated. The prognostic effect of age, primary malignancy, gender, extent of disease, indication, admission to the intensive care unit, and IVC thrombus on overall survival was also evaluated using univariate and multivariate Cox models for patients with solid tumors. RESULTS: The median survival periods for patients with solid and liquid tumors were 145 days and 207 days, respectively. The probability of survival at 30, 90, and 365 days was 0.81, 0.60, and 0.35, respectively, for patients with solid tumors and 0.85, 0.67, and 0.48, respectively, for patients with liquid tumors. There was no statistically significant difference in survival based on primary malignancy for solid tumors (P = 0.628) or between solid and liquid tumors (P = 0.16). For patients with solid tumors, a statistically significant difference in survival was found by extent of disease (P = 0.002). Patients with solid tumors classified as local disease (n = 15), locally advanced disease (n = 95), and widely metastatic or disseminated disease (n = 153) had a probability of survival at 30 days of 0.93, 0.87, and 0.76, respectively. Compared with patients with local disease, patients with metastatic or disseminated disease were 3.7 times more likely to die (P = 0.013). Patients with a history of deep venous thrombosis (DVT) and hemorrhage were 2 times more likely to die than patients with DVT and no history of hemorrhage (P = 0.0057). Documented complications occurred in 22 of 308 (7.1%) patients and included PE (n = 4), new caval thrombosis (n = 14), retroperitoneal hemorrhage (n = 2), and maldeployed filters (n = 2). CONCLUSIONS: IVC filters were shown to be safe and highly effective in preventing PE-related deaths in patients with cancer with VTE disease. Patients with a history of DVT and bleeding or metastatic/disseminated stage of disease had the lowest survival after IVC filter placement.

Vulvar venous malformations in an 11-year-old girl: a case report.

BACKGROUND: Unlike varicosities, which result from venous insufficiency, vascular malformations are developmental errors that do not regress. While these lesions are challenging to treat in most anatomic locations, genital venous malformations are particularly difficult problems for the gynecologist, urologist, or primary care physician who may identify them. The risk of surgical treatment has led to investigation of new therapeutic options for these vascular lesions. CASE: We describe an 11-year-old premenarchal female with bilateral, symptomatic vulvar venous malformations. These lesions were successfully treated with Doppler ultrasound-guided direct injection venography and ethanol sclerotherapy. CONCLUSION: Direct injection venography with ethanol sclerotherapy is an attractive diagnostic and therapeutic option for management of vulvar venous malformations.

Various approaches for CT-guided percutaneous biopsy of deep pelvic lesions: anatomic and technical considerations.

Access route planning for computed tomography-guided biopsy of deep pelvic masses remains challenging because vital structures often obstruct the projected needle path. The classical approach through the lower anterior abdominal wall allows access to lesions located anterior, superior, or lateral to the urinary bladder. However, this approach has limitations: Deep masses are difficult to reach because of intervening structures, the bowel or bladder may be unavoidably traversed, and peritoneal transgression is often painful. A transgluteal approach is useful for biopsy of presacral and perirectal lesions and lesions located posterolateral to the bladder. An anterolateral approach through the iliopsoas muscle allows safe extraperitoneal access to external and internal iliac nodes, masses located along the lateral pelvic sidewall, and adnexal lesions. A transosseous (transsacral or transiliac) approach can occasionally be used for otherwise inaccessible lesions. Use of a curved needle, change in patient position, or injection of saline solution to displace intervening structures may also be helpful. Familiarity with normal cross-sectional pelvic anatomy facilitates planning of a safe access route and helps avoid injury to adjacent structures. A thorough understanding of the advantages and disadvantages of each approach allows the clinician to choose the most appropriate approach in a given situation.