OBJECTIVE: To define the MR appearance of discoid meniscus in children. MATERIALS AND METHODS: In 22 children (15 girls and 7 boys; age range 5-17 years; median age 9 years) who were referred for evaluation of painful knees 27 discoid lateral menisci were identified. Meniscal shape and signal intensity and abnormalities of the surrounding structures were evaluated and compared with adult standards. Clinical (11 knees) or surgical (10 knees) follow-up was available on 16 patients (21 knees). RESULTS: The menisci were classified as slab type (no. 20) or wedge type (no. 7). Transverse diameter at the midbody was 22.4 mm (range 10.5-36.7 mm) for discoid lateral menisci and 6 mm (range 5.1-28.3 mm) for medial menisci. Of 27 menisci, 23 had a central band of diffusely increased signal. Extension of intrameniscal signal to the joint space was noted in 16 of 23 menisci. Of 9 patients with intrameniscal signal who underwent surgery, only 7 had tears. Associated popliteal cysts occurred in 3 knees. No medial meniscal injury was observed. CONCLUSION: The characteristic MRI appearance of symptomatic discoid meniscus in children is that of a diffusely thick meniscus with a slab configuration and diffusely increased intrameniscal signal that may or may not extend to the joint surface.

Child↗

PubMedDate not supplied

CT and ultrasound imaging of retropharyngeal abscesses in children.

PURPOSE: To show the role of ultrasound (US) in distinguishing retropharyngeal abscess from adenitis in children. METHODS: Eleven infants and children had clinical symptoms suggestive of retropharyngeal infection. Radiographic evaluation included, lateral neck radiography (11/11), contrast-enhanced neck CT (10/11), contrast-enhanced neck MR (1/11), and real time US (11/11) patients. US was used to characterize masses as solid (adenitis) or complex (abscess) and for guiding intraoperative aspiration and drainage. RESULTS: Contrast CT and MR showed findings suspicious for abscess in all 11 cases. Only three children had surgically drainable abscesses. CT numbers within inflammatory masses did not distinguish adenitis from abscess. US was able to correctly diagnose abscess or adenitis in each case. CONCLUSION: Lateral neck radiography and contrast CT identify and localize retropharyngeal inflammatory masses in children. US, but not CT, distinguishes between adenitis and abscess and aids in intraoperative aspiration and drainage.

Abscess↗

PubMedDate not supplied

MR demonstration of ectopic fourth ventricular choroid plexus in Chiari II malformation.

An enhancing nodule was seen on T1-weighted enhanced scans at the tip of the caudally displaced cerebellar vermis in three patients with Chiari II malformation. The enhancing fibrovascular nodule found at the base of the cerebellum in patients with Chiari II malformation represents ectopic choroid plexus and should not be confused with a pathologic mass.

Arnold-Chiari Malformation↗