No abstract

Fibromuscular dysplasia (FMD), a disease well described in the renal and cerebrovascular circulations, also manifests in the lower extremity (LE) arteries. This study reports on the clinical presentation, imaging findings, and treatment of patients with LE FMD seen at a single center. Over a 7-year span, 100 of 449 patients with FMD had imaging of the LE arteries, of which 62 were found to have LE FMD (13.8% of the entire FMD cohort including patients with and without LE imaging). The majority of patients were women (96.8%), with an average age of 52 ± 11.3 years at the time of diagnosis. All patients had FMD present in another vascular bed, most commonly in the renal (80.6%) and extracranial carotid arteries (79.0%). Most patients had multifocal FMD (95.2%) and bilateral LE disease (69.4%), with the external (87.1%), common (19.4%), and internal (11.3%) iliac arteries most commonly affected. Presenting symptoms of LE involvement included claudication (22.6%), atypical leg symptoms (14.5%), and dissection (6.5%), but most patients were asymptomatic (71.0%). Nearly all patients were managed conservatively (98.4%) and only 1 patient required intervention.

Cholesterol crystal emboli triggered muscle inflammation and necrosis with an intact circulation. PET/CTA may help in the early detection of inflammation caused by CCs.

Cholesterol crystal embolic (CCE) syndrome is often a clinically challenging condition that has a poor prognostic implication. It is a result of plaque rupture with release of cholesterol crystals into the circulation that embolize into various tissue organs. Plaque rupture seems to be triggered by an expanding necrotic core during cholesterol crystallization forming sharp tipped crystals that perforate and tear the fibrous cap. Embolizing cholesterol crystals then initiate both local and systemic inflammation that eventually lead to vascular fibrosis and obstruction causing symptoms that can mimic other vasculitic conditions. In fact, animal studies have demonstrated that cholesterol crystals can trigger an inflammatory response via NLRP3 inflammasome similar to that seen with gout. The diagnosis of CCE syndrome often requires a high suspicion of the condition. Serum inflammation biomarkers including elevated sedimentation rate, abnormal renal function tests and eosinophilia are useful but non-specific. Common target organ involvement includes the skin, kidney, and brain. Various testing including fundoscopic eye examination and other non-invasive procedures such as trans-esophageal echocardiography and magnetic resonance imaging may be helpful in identifying the embolic source. Treatment includes aspirin and clopidogrel, high dose statin and possibly steroids. In rare cases, mechanical intervention using covered stents may help isolate the ruptured plaque. Anticoagulation with warfarin is not recommended and might even be harmful. Overall, CCE syndrome is usually a harbinger of extensive and unstable atherosclerotic disease that is often associated with acute cardiovascular events.

Structural components of composite materials in aerospace industries are assembled using fasteners, installed by performing cutting processes, such as drilling, on the material. In composites, this is considered particularly critical, because delamination due to mechanical stresses and fiber/resin pullout may be facilitated during cutting, so that the structural integrity of composite laminates may be affected. Acoustic emission (AE) technique is employed to monitor the failure modes and damage mechanism of drilled composite materials, while in an attempt to improve the strength of the composites, thermal conditioning has been applied. This paper investigates the residual performance of drilled unidirectional glass fiber reinforced plastic (GFRP) laminates subjected to various thermal conditioning methods. Thermally treated laminates underwent three-point flexural tests under AE monitoring to compare their residual strength with the untreated ones. The results clearly show that the thermal conditioning could be used as an effective method for minimizing delamination in GFRPs.