US-guided Musculoskeletal Interventions in the Hip with MRI and US Correlation.

Hip pain is a commonly reported primary symptom with many potential causes. The causal entity can remain elusive, even after clinical history review, physical examination, and diagnostic imaging. Although there are many options for definitive treatment, many of these procedures are invasive, are associated with risk of morbidity, and can be unsuccessful, with lengthy revision surgery required. Percutaneous musculoskeletal intervention is an attractive alternative to more invasive procedures and an indispensable tool for evaluating and managing hip pain. US is an ideal modality for imaging guidance owing to its low cost, portability, lack of ionizing radiation, and capability for real-time visualization of soft-tissue and bone structures during intervention. The authors review both common and advanced US-guided procedures involving the pelvis and hip, including anesthetic and corticosteroid injections, percutaneous viscosupplementation, platelet-rich plasma injection to promote tendon healing, and microwave ablation for neurolysis. In addition, specific anatomic structures implicated in hip pain are discussed and include the hip joint, iliopsoas bursa, ilioinguinal nerve, lateral femoral cutaneous nerve, greater trochanteric bursa, iliotibial band, ischiogluteal bursa, hamstring tendon origin, piriformis muscle, and quadratus femoris muscle. The relevant US-depicted anatomy and principles underlying technically successful interventions also are discussed. Familiarity with these techniques can aid radiologists in assuming an important role in the care of patients with hip pain. ©RSNA, 2019.

Gadolinium-Based Contrast Agents in Kidney Disease: Comprehensive Review and Clinical Practice Guideline Issued by the Canadian Association of Radiologists.

Use of gadolinium-based contrast agents (GBCAs) in renal impairment is controversial, with physician and patient apprehension in acute kidney injury (AKI), chronic kidney disease (CKD), and dialysis because of concerns regarding nephrogenic systemic fibrosis (NSF). The position that GBCAs are absolutely contraindicated in AKI, CKD stage 4 or 5 (estimated glomerular filtration rate [eGFR] <30 mL/min/1.73 m2) and dialysis-dependent patients is outdated, and may limit access to clinically necessary contrast-enhanced MRI examinations. Following a comprehensive review of the literature and reported NSF cases to date, a committee of radiologists and nephrologists developed clinical practice guidelines to assist physicians in making decisions regarding GBCA administrations. In patients with mild-to-moderate CKD (eGFR ≥30 and <60 mL/min/1.73 m2), administration of standard doses of GBCA is safe and no additional precautions are necessary. In patients with AKI, with severe CKD (eGFR <30 mL/min/1.73 m2), or on dialysis, administration of GBCAs should be considered individually and alternative imaging modalities utilized whenever possible. If GBCAs are necessary, newer GBCAs may be administered with patient consent obtained by a physician (or their delegate), citing an exceedingly low risk (much less than 1%) of developing NSF. Standard GBCA dosing should be used; half or quarter dosing is not recommended and repeat injections should be avoided. Dialysis-dependent patients should receive dialysis; however, initiating dialysis or switching from peritoneal to hemodialysis to reduce the risk of NSF is unproven. Use of a macrocyclic ionic instead of macrocyclic nonionic GBCA or macrocyclic instead of newer linear GBCA to further prevent NSF is unproven. Gadopentetate dimeglumine, gadodiamide, and gadoversetamide remain absolutely contraindicated in patients with AKI, with stage 4 or 5 CKD, or on dialysis. The panel agreed that screening for renal disease is important but less critical when using macrocyclic and newer linear GBCAs. Monitoring for and reporting of potential cases of NSF in patients with AKI or CKD who have received GBCAs is recommended.