Pictorial review: Renal ultrasound.

Ultrasound (US) is the first-line imaging modality for evaluating azotemic patients for urinary obstruction and renal size. US is also valuable for distinguishing congenital variants and simple cystic lesions from renal masses. Doppler US is effective in detection of renal calculi and evaluation of vascular pathology. Unfortunately, renal US is limited in distinguishing causes of medical renal disease. The kidneys have a complex internal architecture with a highly variable appearance on US. This article illustrates non-neoplastic renal conditions, including normal and embryological variants, parenchymal, cystic, and vascular diseases. Renal infections, calcifications, and trauma and fluid collections are also discussed, with an emphasis on distinguishing US features and pathophysiology.

US and MR Imaging of Pectoralis Major Injuries.

During the past 2 decades, the frequency of pectoralis major muscle injuries has increased in association with the increased popularity of bench press exercises. Injury of the pectoralis major can occur at the muscle origin, muscle belly, musculotendinous junction, intratendinous region, and/or humeral insertion-with or without bone avulsion. The extent of the tendon injury ranges from partial to complete tears. Treatment may be surgical or conservative, depending on the clinical scenario and anatomic characteristics of the injury. The radiologist has a critical role in the patient's treatment-first in detecting and then in characterizing the injury. In this article, the authors review the normal anatomy and anatomic variations of the pectoralis major muscle, classifications and typical patterns of pectoralis major injuries, and associated treatment considerations. The authors further provide an instructive guide for ultrasonographic (US) and magnetic resonance (MR) imaging evaluation of pectoralis major injuries, with emphasis on a systematic approach involving the use of anatomic landmarks. After reviewing this article, the reader should have an understanding of how to perform-and interpret the findings of-US and MR imaging of the pectoralis major. The reader should also understand how to classify pectoralis major injuries, with emphasis on the key findings used to differentiate injuries for which surgical management is required from those for which nonsurgical management is required. Familiarity with the normal but complex anatomy of the pectoralis major is crucial for performing imaging-based evaluation and understanding the injury findings. ©RSNA, 2017 Online supplemental material is available for this article.

Serial magnetic resonance imaging findings of intracerebral spread of listeria utilising subcortical U-fibres and the extreme capsule.

We present a case of Listeria monocytogenes cerebral abscess with axonal spread via the subcortical U-fibres and extreme capsule on magnetic resonance imaging, with follow-up studies demonstrating serial reduction in oedema and enhancement pattern of the white-matter fibre tracts following antimicrobial treatment. We discuss the microbiological mechanism of bacterial mobility to account for these unique imaging features. Recognition of this distinct pattern of spread of L. monocytogenes cerebral abscess may aid in diagnosis and enable early microbiological culture and treatment.

High resolution CT study of the chorda tympani nerve and normal anatomical variation.

OBJECTIVE: The aim of this study was to define the normal anatomical variation of the course of the CTN through the mastoid temporal bone on high resolution CT (HRCT). MATERIALS AND METHODS: Retrospective review of 27 consecutive normal HRCT bilateral temporal bones (n = 54, 14 males and 13 females, mean age 41 years) reconstructed at 0.4-mm slice thickness specifically measuring (1) origin of CTN from the posterior genu of the facial nerve (CNVII) and (2) the lateral-most position of the CTN from the mastoid segment of CNVII. RESULTS: The mean distance of the CTN origin from the mastoid segment of CNVII was 11.5 mm (standard deviation, SD = 3.2, 95% CI 10.7-12.3) with no statistically significant difference between the left and right side observed (p = 0.08). The most lateral distance of the CTN from CNVII was a mean of 1.3 mm (SD = 0.6, 95% CI 1.2-1.7), range 0-2.5 mm and again no statistical significance between contralateral sides was observed (p = 0.11). These measurements demonstrated an excellent level of agreement between observers as assessed by intraclass correlation calculation. CONCLUSIONS: Reproducible measurements demonstrate variability of the CTN in both its origin from the mastoid segment of CNVII and its lateral-most course. Precise description of the course of the CTN with HRCT may be useful for planning of otologic surgery and limiting inadvertent nerve injury.

Coronal plane fracture of the femoral condyles: anatomy, injury patterns, and approach to management of the Hoffa fragment.

OBJECTIVE: The purpose of this article is to provide a review of coronal fractures of the femoral condyles, known as Hoffa fractures. This includes a review of the normal anatomy of the femoral condyles, examples of the injury, and postoperative imaging findings after surgical treatments. CONCLUSIONS: Knowledge of anatomy with related pathology, orthopedic trends, imaging findings, and complications, is important in assessing Hoffa fractures.