Presence Of Vascular Occlusion Research Articles

A Curious Case of “Septic Shock”

BackgroundTakayasu arteritis, also known as “pulseless disease,” causes proximal occlusion of the lumen of large arteries of the neck and arm, leading to impalpable pulses and “pseudohypotension.” This may misdirect the management plan for a patient in the emergency setting if the presence of vascular occlusion is not previously known. Case ReportWe describe a young woman who presented to the emergency department (ED) with fever. On evaluation, she had shock, which was not responsive to a fluid bolus. Bedside Rapid Diagnostic Test was positive for Plasmodium vivax, and a diagnosis of severe vivax malaria was made. She was started on intravenous artesunate and vasopressors in view of her persistent hypotension in the face of a normal central venous pressure. A thorough examination at that time revealed palpable lower limb pulses with feeble upper limb pulses. Vasopressors were tapered while monitoring lower limb blood pressure. Computed tomographic angiogram confirmed the diagnosis of Takayasu arteritis. Why Should an Emergency Physician Be Aware of This?Hypotension and shock are regularly encountered in the ED. Occlusive arterial disease involving upper limbs can mimic refractory shock, leading to potentially harmful and unnecessary interventions. Emergency physicians should be aware of this possibility. A simple routine of quickly checking all peripheral pulses would help them avoid this pitfall.

Radiological features of IgG4-related disease in the head, neck, and brain

Immunoglobulin (Ig) G4-related disease is a recently designated benign clinical entity histopathologically characterized by sclerosing inflammation and infiltration of numerous IgG4+ plasma cells that affects multiple organs. The purpose of this study is to characterize the imaging findings of patients with histopathologically proven IgG4-related disease in the head, neck, and brain. A total of 17 patients (15 males, 2 females; mean age, 66.1 ± 7.4years) with histopathologically proven IgG4-related disease in the head, neck, and brain were identified in two hospitals between January 2004 and December 2010. Imaging findings were retrospectively reviewed, with particular attention to the location and number of lesions, internal architecture, enhancement patterns, presence of vascular occlusion or compression, and changes in adjacent bones. The lesions, presented as either enlarged gland(s), or focal, localized nodules/masses, were distributed in the lacrimal gland (n = 7), the parotid gland (n = 14), the submandibular gland (n = 10), the pituitary gland (n = 2), skull base dura mater (n = 2), and the pterygopalatine fossa (n = 3). All lesions were well-defined and iso- to hypointense on T2-weighted magnetic resonance images and showed homogeneous enhancement. No lesion showed vascular occlusion or compression. Bones adjacent to the lesions showed remodeling (erosion or sclerosis) without signs of destruction (n = 6). Four patients had lesions involving multiple areas which extended along the trigeminal nerve, accompanied by expansion of neural foramina along their courses, with no signs of bone destruction. Sites of predilection for IgG4-related disease in the head, neck, and brain include the lacrimal, salivary, and pituitary glands. Recognition of the typical radiological features of IgG4-related disease, such as well-defined lesion borders, T2 hypointensity, homogeneous and gradual enhancement pattern, absence of vascular occlusion or compression, and presence of bone remodeling without destruction, may be of help in the diagnosis of this benign clinical entity.

Actinomycosis of the Nasopharynx Causing Carotid Occlusion

Actinomycosis is a chronic, fibrotic infection caused by gram-positive bacteria that can mimic destructive processes such as malignancy or tuberculosis. Cervicofacial actinomycosis is the most common clinical form of actinomycosis and should be considered in the differential diagnosis of aggressive lesions of the nasopharynx. A case of actinomycosis of the nasopharynx extending to the skull base and resulting in occlusion of the internal carotid artery is presented. The presence of vascular occlusion by an infiltrative process, disproportionate bony destruction relative to the soft tissue involvement and lack of adenopathy should raise the suspicion of an inflammatory process as the etiology and not a tumor.

Effect of perfusion on exercised muscle: MR imaging evaluation.

An ischemic clamp model of exercise was used to evaluate the potential role of blood flow in mediating changes in the magnetic resonance imaging appearance of skeletal muscle. Proton relaxation times of muscle were serially estimated in 10 healthy subjects (a) before exercise, (b) after exercise in the presence of vascular occlusion (VO1), (c) during vascular reocclusion after 1 minute of reperfusion (VO2), and (d) after reinstitution of continuous flow. T1 and T2 of active muscles were increased during VO1. During VO2, there were additional increases in relaxation times of active muscles. Reinstitution of continuous flow was associated with a continuous decrease in the T2 of exercised muscle. Hence, blood flow was not required for increases in T1 and T2 with exercise. Additional relaxation time increases occurred after a brief period of reperfusion; however, continuous flow was associated with a decrease in T2.