A Case of Metronidazole-Induced Encephalopathy: Atypical Involvement of the Brain on MRI

Metronidazole is an antimicrobial agent widely used for the treatment of anaerobic infection or antibiotics-associated diarrhea. It is generally thought to be safe, but can induce reversible toxic encephalopathy in the case of excessive or cumulative over-dose. Metronidazole-induced encephalopathy generally demonstrates the characteristic features of typical lesion location and bilaterality on magnetic resonance imaging (MRI). We report a case of metronidazole-induced encephalopathy with the involvement of asymmetric white matter. To our knowledge, only a few cases have been reported with respect to white matter lesion characteristics on MRI with diffusion-weighted images.

Comparison of Metal Artifact Reduction for Orthopedic Implants versus Standard Filtered Back Projection: Value of Postoperative CT after Hip Replacement

PURPOSE@#To evaluate Metal Artifact Reduction for Orthopedic Implants (O-MAR, Philips Healthcare) technique compared with standard filtered back projection (SFBP) technique on post-operative hip CT regarding image noise reduction and detection of post-operative complications.@*MATERIALS AND METHODS@#Fifty-six hip CT scans after hip replacement with SFBP technique and O-MAR application were retrospectively reviewed. Region of interests (ROIs) were drawn at levels wherein acetabular cup and femoral head were largest at anterior and posterior acetabula, gluteus maximus muscle, subcutaneous fat adjacent to gluteus maximus muscle, and in area adjacent to prosthesis stem wherein lesser trochanter is largest. Hounsfield units (HU) were measured to evaluate artifact quantitatively; mean and standard deviations (SDs) calculated and compared. Periprosthetic complications were evaluated, and visibility rated between two reconstruction techniques; 1-SFBP better, 2–SFBP same as O-MAR, 3–O-MAR better.@*RESULTS@#Average HU was significantly lower in O-MAR at posterior acetabulum, gluteus maximus muscle, and subcutaneous fat (p < 0.05). SD for HU was significantly lower in O-MAR at all ROIs (p < 0.05). Mean visibility of periprosthetic complications was 2.0, so equivalent.@*CONCLUSION@#Reconstruction with O-MAR technique in post-operative hip CT scans after hip replacement yielded statistically significant decrease in image noise. However, visibility of periprosthetic complications was not impacted by reconstruction technique.

Clear Cell Sarcoma of the Wrist: MRI Findings with Diffusion-Weighted Image and Histopathologic Correlation

Clear cell sarcoma is rare and difficult to diagnose. Herein, we present a case of clear cell sarcoma in the dorsum of the wrist with MRI findings, including diffusion-weighted imaging, and histopathologic correlation, which was initially diagnosed as giant cell tumor of tendon sheath.

Current status of ultrasonography of the finger

The recent development of advanced high-resolution transducers has enabled the fast, easy, and dynamic ultrasonographic evaluation of small, superficial structures such as the finger. In order to best exploit these advances, it is important to understand the normal anatomy and the basic pathologies of the finger, as exemplified by the following conditions involving the dorsal, volar, and lateral sections of the finger: sagittal band injuries, mallet finger, and Boutonnière deformity (dorsal aspect); flexor tendon tears, trigger finger, and volar plate injuries (volar aspect); gamekeeper's thumb (Stener lesions) and other collateral ligament tears (lateral aspect); and other lesions. This review provides a basis for understanding the ultrasonography of the finger and will therefore be useful for radiologists.