Maria F. Ladino-Torres

A critical evaluation of US for the diagnosis of pediatric acute appendicitis in a real-life setting: how can we improve the diagnostic value of sonography?

BackgroundWe have observed that day-to-day use of US for acute appendicitis does not perform as well as described in the literature.ObjectiveReview the diagnostic performance of US in acute appendicitis with attention to factors that influence performance.Materials and methodsRetrospective review of all sonograms for acute appendicitis in children from May 2005 to May 2010 with attention to the rate of identification of the appendix, training of personnel involved and diagnostic accuracy.ResultsThe appendix was identified in 246/1,009 cases (24.4%), with identification increasing over time. The accuracy of US was 85–91% with 35 false-positives and 54 false-negatives. Pediatric sonographers were significantly better at identifying the appendix than non-pediatric sonographers (P < 0.0001). Increased weight was the only patient factor that influenced identification of the appendix (P = 0.006). CT use was stable over the 5 years but declined in cases where the appendix was identified by US.ConclusionIn day-to-day use, US does not perform as purported in the literature. We do not visualize the appendix as often as we should and false-negative and false-positive exams are too common. To improve the diagnostic performance of this modality, involvement by experienced personnel and/or additional training is needed.

Reevaluating the sonographic criteria for acute appendicitis in children: a review of the literature and a retrospective analysis of 246 cases.

RATIONALE AND OBJECTIVES There has been little rigorous evaluation of the sonographic criteria for acute appendicitis in children. Our clinical experience has called the traditional diagnostic criteria into question. We set out to review the literature, evaluate the most commonly applied diagnostic criteria for acute appendicitis, and identify those criteria that best predict the presence of disease. MATERIALS AND METHODS A critical review of the literature concerning the sonographic diagnosis of acute appendicitis was performed. Based on diagnostic criteria identified in that review, two independent, blinded pediatric radiologists retrospectively reviewed 246 right lower quadrant ultrasound examinations in which the appendix was identified with attention to commonly described diagnostic criteria for acute appendicitis. Multivariate and classification and regression tree analysis were performed to identify criteria that predict appendicitis. RESULTS In a multivariate analysis, inflammation of the periappendiceal fat is the only finding that statistically significantly predicts acute appendicitis (OR = 68.93, P < .0001). Other criteria such as diameter, noncompressibility, hyperemia, the presence of an appendicolith, and loss of stratification of the appendiceal wall do not independently predict appendicitis. CONCLUSION Periappendiceal fat infiltration is the most important diagnostic criterion for acute appendicitis in children. Strict application of other criteria such as diameter should be avoided.

Expanding upon the Unilateral Hyperlucent Hemithorax in Children

Unilateral hyperlucent hemithorax is a common pediatric chest radiographic finding that may also be seen at computed tomography. It may result from congenital or acquired conditions involving the pulmonary parenchyma, airway, pulmonary vasculature, pleural space, and chest wall, as well as from technical factors such as patient rotation. Unilateral hyperlucent hemithorax has a broad differential diagnosis that includes unilateral emphysematous or bullous disease, pneumatocele, foreign body aspiration, Swyer-James syndrome, congenital lobar emphysema, endobronchial mass, unilateral pulmonary agenesis, proximal interruption of the pulmonary artery, scimitar syndrome, diaphragmatic hernia, and Poland syndrome. Although certain causes of unilateral hyperlucent hemithorax are clinically significant and potentially life threatening, others are of minimal or no clinical significance. When evaluating a patient with this finding, it is important to establish whether the apparent unilateral hyperlucent hemithorax is truly too lucent (hypoattenuating) or if the contralateral hemithorax is too opaque (hyperattenuating). It is imperative that radiologists be aware of the various causes of unilateral hyperlucent hemithorax so that they may diagnose the underlying condition and appropriately guide patient management.

Another dimension to survival: predicting outcomes with fetal MRI versus prenatal ultrasound in patients with congenital diaphragmatic hernia.

PURPOSE A major determinant of survival in patients with congenital diaphragmatic hernia (CDH) is severity of pulmonary hypoplasia. This study addresses the comparative effectiveness of prenatal methods of lung assessment in predicting mortality, extracorporeal membrane oxygenation (ECMO), and ventilator dependency. METHODS We retrospectively reviewed all patients born with isolated CDH between 2004 and 2008. Lung-to-head ratio (LHR) and observed-to-expected LHR (OELHR) were obtained from prenatal ultrasounds. Percent-predicted lung volume (PPLV) was obtained from fetal MRI (fMRI). Postnatal data included in-hospital mortality, need for ECMO, and ventilator dependency at day-of-life 30. RESULTS Thirty-seven patients underwent 81 prenatal ultrasounds, while 26 of this sub-cohort underwent fMRI. Gestational age during imaging study was associated with LHR (p=0.02), but not OELHR (p=0.12) or PPLV (p=0.72). PPLV, min-LHR, and min-OELHR were each associated with mortality (p=0.03, p=0.02, p=0.01), ECMO (p<0.01, p<0.01, p=0.03), and ventilator dependency (p<0.01, p<0.01, p=0.02). For each outcome, PPLV was a more discriminative measure, based on Akaikes information criterion. Using longitudinal analysis techniques for patients with multiple ultrasounds, OELHR remained associated with mortality (p=0.04), ECMO (p=0.03), and ventilator dependency (p=0.02), while LHR was associated with ECMO (p=0.01) and ventilator dependency (p=0.02) but not mortality (p=0.06). CONCLUSION When assessing fetuses with CDH, OELHR and PPLV may be most helpful for counseling regarding postnatal outcomes.

MR enterography of perforated acute Meckel diverticulitis

Meckel diverticulum is the most common congenital anomaly of the small intestine that generally comes to attention due to a variety of complications, such as gastrointestinal tract bleeding, bowel obstruction or acute inflammation. These diverticula frequently are difficult to prospectively diagnose by imaging. Clinically, acute Meckel diverticulitis can be mistaken for acute appendicitis or Crohn disease. We present a 6-year-old boy with perforated acute Meckel diverticulitis that mimicked Crohn disease both clinically and by CT imaging and was definitively diagnosed using MR enterography.

Gastrointestinal Tumors in Children

Although tumors arising from the spleen, pancreas, and gastrointestinal tract in the pediatric population are relatively uncommon, imaging plays an important role in diagnosis, staging, and treatment planning. Initial imaging with abdominal radiograph contributes to the evaluation for intestinal obstruction, constipation, and mass effect, and sometimes may reveal areas of calcification.

Prenatal and postnatal markers of severity in congenital diaphragmatic hernia have similar prognostic ability.

The purpose of this study was to compare prenatal versus postnatal markers of congenital diaphragmatic hernia (CDH) severity at a single fetal‐care center.

MR enterography of ileocolovesicular fistula in pediatric Crohn disease

Crohn disease, a form of chronic inflammatory bowel disease is characterized by discontinuous inflammatory lesions of the gastrointestinal tract, has a variety of behavioral patterns, including penetrating or fistulous disease. While magnetic resonance enterography (MRE) excellently depicts inflamed bowel segments, it can also be used to assess for a variety of Crohn-disease-related extraintestinal complications, including fistulae. We present the MRE findings of a complex ileocolovesicular fistula in a 14-year-old boy with Crohn disease, where the fistulous tract to the urinary bladder was best delineated on precontrast T1-W imaging because of the presence of fecal material.

Diffuse uterine leiomyomatosis in a child

Leiomyomas are the most common benign uterine tumor; however, this entity is relatively uncommon in the pediatric population. Although leiomyomas most commonly present as solitary uterine masses, unusual patterns of growth have been described including diffuse leiomyomatosis. In this condition, the myometrium of the uterus is symmetrically expanded by innumerable confluent leiomyomas; this pattern of growth is quite uncommon and has never been reported in a pediatric patient. This case report illustrates the imaging appearance of diffuse uterine leiomyomatosis in an otherwise healthy 16-year-old girl.

Inter-radiologist agreement for CT scoring of pediatric splenic injuries and effect on an established clinical practice guideline

BackgroundThe American Pediatric Surgical Association (APSA) advocates for the use of a clinical practice guideline to direct management of hemodynamically stable pediatric spleen injuries. The clinical practice guideline is based on the CT score of the spleen injury according to the American Association for the Surgery of Trauma (AAST) CT scoring system.ObjectiveTo determine the potential effect of radiologist agreement for CT scoring of pediatric spleen injuries on an established APSA clinical practice guideline.Materials and methodsWe retrospectively analyzed blunt splenic injuries occurring in children from January 2007 to January 2012 at a single level 1 trauma center (n = 90). Abdominal CT exams performed at clinical presentation were reviewed by four radiologists who documented the following: (1) splenic injury grade (AAST system), (2) arterial extravasation and (3) pseudoaneurysm. Inter-rater agreement for AAST injury grade was assessed using the multi-rater Fleiss kappa and Kendall coefficient of concordance. Inter-rater agreement was assessed using weighted (AAST injury grade) or prevalence-adjusted bias-adjusted (binary measures) kappa statistics; 95% confidence intervals were calculated. We evaluated the hypothetical effect of radiologist disagreement on an established APSA clinical practice guideline.ResultsInter-rater agreement was good for absolute AAST injury grade (kappa: 0.64 [0.59–0.69]) and excellent for relative AAST injury grade (Kendall w: 0.90). All radiologists agreed on the AAST grade in 52% of cases. Based on an established clinical practice guideline, radiologist disagreement could have changed the decision for intensive care management in 11% (10/90) of children, changed the length of hospital stay in 44% (40/90), and changed the time to return to normal activity in 44% (40/90).ConclusionRadiologist agreement when assigning splenic AAST injury grades is less than perfect, and disagreements have the potential to change management in a substantial number of pediatric patients.