Faculty Bibliography

BACKGROUND: Rapid and accurate diagnosis of appendicitis, particularly with respect to the presence or absence of perforation, is essential in guiding appropriate management. Although many studies have explored sonographic findings associated with acute appendicitis, few investigations discuss specific signs that can reliably differentiate perforated appendicitis from acute appendicitis prior to abscess formation. OBJECTIVE: The purpose of our study was to identify sonographic findings that improve the specificity of US in the diagnosis of perforated appendicitis. Our assessment of hepatic periportal echogenicity, detailed analysis of intraperitoneal fluid, and formulation of select constellations of sonographic findings expands upon the literature addressing this important diagnostic challenge. MATERIALS AND METHODS: We retrospectively reviewed 116 abdominal US examinations for evaluation of abdominal pain in children ages 2 to 18 years from January 2008 to September 2011 at a university hospital pediatric radiology department. The study group consisted of surgical and pathology proven acute appendicitis (n = 51) and perforated appendicitis (n = 22) US exams. US exams without a sonographic diagnosis of appendicitis (n = 43) confirmed by follow-up verbal communication were included in the study population as the control group. After de-identification, the US exams were independently reviewed on a PACS workstation by four pediatric radiologists blinded to diagnosis and all clinical information. We recorded the presence of normal or abnormal appendix, appendicolith, appendiceal wall vascularity, thick-walled bowel, dilated bowel, right lower quadrant (RLQ) echogenic fat, increased hepatic periportal echogenicity, bladder debris and abscess or loculated fluid. We also recorded the characteristics of intraperitoneal fluid, indicating the relative quantity (number of abdominal regions) and quality of the fluid (simple fluid or complex fluid). We used logistic regression for correlated data to evaluate the association of diagnosis with the presence versus absence of each US finding. We conducted multivariable analysis to identify constellations of sonographic findings that were predictive of perforated appendicitis. RESULTS: The individual US findings of abscess/loculated fluid, appendicolith, dilated bowel and increased hepatic periportal echogenicity were significantly associated with perforated appendicitis when compared with acute appendicitis (P < 0.01). The sonographic observation of increased hepatic periportal echogenicity demonstrated a statistically significant association with perforated appendicitis compared with acute appendicitis (P < 0.01). The presence of complex fluid yielded a specificity of 87.7% for perforated appendicitis compared with the acute appendicitis group. The US findings of >/=2 regions or >/=3 regions with fluid had specificity of 87.3% and 99.0%, respectively, for perforated appendicitis compared with the acute appendicitis group. Select combinations of sonographic findings yielded high specificity in the diagnosis of perforated appendicitis compared with acute appendicitis. These constellations yielded higher specificity than that of each individual finding in isolation. The constellation of dilated bowel, RLQ echogenic fat, and complex fluid had the highest specificity (99.5%) for perforated appendicitis (P < 0.01). CONCLUSION: Our study demonstrates that identification of select constellations of findings using abdominal sonography, in addition to focused US examination of the right lower quadrant, can improve sonographic diagnosis of perforated appendicitis in the pediatric population.

Gliomatosis peritonei is a rare condition associated with ovarian teratomas. Even rarer is extraperitoneal gliomatosis. We present a case of extraperitoneal gliomatosis with pleural implants and implants within the flank muscles, which regressed after resection of the primary tumor.

OBJECTIVE: To compare the image quality of contrast-enhanced abdominopelvic 3D fat-suppressed T1-weighted gradient-echo imaging with radial and conventional Cartesian k-space acquisition schemes in paediatric patients. METHODS: Seventy-three consecutive paediatric patients were imaged at 1.5 T with sequential contrast-enhanced T1-weighted Cartesian (VIBE) and radial gradient echo (GRE) acquisition schemes with matching parameters when possible. Cartesian VIBE was acquired as a breath-hold or as free breathing in patients who could not suspend respiration, followed by free-breathing radial GRE in all patients. Two paediatric radiologists blinded to the acquisition schemes evaluated multiple parameters of image quality on a five-point scale, with higher score indicating a more optimal examination. Lesion presence or absence, conspicuity and edge sharpness were also evaluated. Mixed-model analysis of variance was performed to compare radial GRE and Cartesian VIBE. RESULTS: Radial GRE had significantly (all P < 0.001) higher scores for overall image quality, hepatic edge sharpness, hepatic vessel clarity and respiratory motion robustness than Cartesian VIBE. More lesions were detected on radial GRE by both readers than on Cartesian VIBE, with significantly higher scores for lesion conspicuity and edge sharpness (all P < 0.001). CONCLUSION: Radial GRE has better image quality and lesion conspicuity than conventional Cartesian VIBE in paediatric patients undergoing contrast-enhanced abdominopelvic MRI. KEY POINTS: * Numerous techniques are required to provide optimal MR images in paediatric patients. * Radial free-breathing contrast-enhanced acquisition demonstrated excellent image quality. * Image quality and lesion conspicuity were better with radial than Cartesian acquisition. * More lesions were detected on contrast-enhanced radial than on Cartesian acquisition. * Radial GRE can be used for performing abdominopelvic MRI in paediatric patients.

BACKGROUND: Shielding of the gonads is a dose-saving strategy in pediatric radiography and its use is the law in New York and the majority of other states. However, routine use of gonadal shields is controversial because of concerns that important diagnostic information can be obscured. OBJECTIVE: The purpose of this study was to assess the frequency and spatial distribution of key findings on portable neonatal abdominal radiographs. MATERIALS AND METHODS: We reviewed the 2,544 portable neonatal intensive care unit anteroposterior abdominal radiographs performed in 2010 at a university medical center, of which 962 were inadequately shielded. These 962 radiographs were reviewed by pairs of pediatric radiologists for the presence of findings in different regions, including bowel abnormalities, pneumatosis, free air, inguinal hernias, osseous abnormalities, and catheter/tube tips. RESULTS: The fewest pertinent findings were present below the level of the sacrosciatic notches (n = 181, 18.8%). Of the 853 abnormalities below the level of the iliac crests in our cohort, six were isolated to these regions, whereas others had concomitant abnormalities more superiorly. Of 35 radiographs with pneumatosis or suspected pneumatosis in the pelvis, 33 had pneumatosis in more superior regions. Suspected free air was never isolated to the pelvis. Osseous abnormalities were only present in the pelvis below the sacrosciatic notch, and 37.5% of lower extremity catheters terminated below the level of the sacrosciatic notches. CONCLUSION: Pertinent findings on neonatal intensive care unit abdominal radiographs are rarely isolated to the pelvic regions.

Purpose or Case Report: Distinguishing perforated from non-perforated appendicitis in children, a known limitation of ultrasound, may alter surgical management. We evaluated the diagnostic utility of select groups of sonographic findings for diagnosis of perforated appendicitis. Methods & Materials: With IRB approval, we retrospectively reviewed 116 abdominal ultrasound (US) exams obtained for evaluation of abdominal pain in children aged 2-18 years from 1/2008 to 9/2011 at a university hospital pediatric radiology department. The study group consisted of surgical and pathology proven acute appendicitis (n=51) and perforated appendicitis (n=22) US exams. Negative US exams for appendicitis (n=43) confirmed by follow up verbal communication comprised the control group. The de-identified US exams were independently reviewed on PACS workstations by four experienced pediatric radiologists blinded to diagnosis and clinical information. The radiologists recorded the presence of dilated bowel, right lower quadrant (RLQ) echogenic fat, increased hepatic periportal echogenicity, and intraperitoneal fluid, indicating quantity (number of abdominal quadrants) and quality of the fluid (simple or complex). Logistic regression for correlated data was used to evaluate the association of diagnosis with the presence versus absence of each US finding in addition to selected groups of US findings. Results: The select groups of findings included increased hepatic periportal echogenicity, echogenic fat, and complex fluid yielding a specificity of 95.0%for perforated appendicitis; increased hepatic periportal echogenicity and 2+ quadrants of fluid yielding a specificity of 96.1%; increased hepatic periportal echogenicity and dilated bowel with a specificity of 98.0%; and dilated bowel, echogenic fat and complex fluid with a specificity of 99.5%. The above constellations of sonographic findings yielded higher specificities than that of each of the following individual findings in isolation: presence of complex fluid (9!