Current Endovascular Treatment Options in Acute Pulmonary Embolism.

Acute pulmonary embolism (PE) is a significant cause of mortality and morbidity across the globe. Over the last few decades, there have been major therapeutic advances in acute PE management, including catheter-based therapy. However, the effectiveness of catheter-based therapy in acute PE is not supported by Level I evidence, making the use of this promising treatment rather controversial and ambiguous. In this paper, we discuss the risk stratification of acute PE and review the medical and endovascular treatment options. We also summarize and review the data supporting the use of endovascular treatment options in acute PE and describe the potential role of the PE response team.

The Pain Crisis: Interventional Radiology's Role in Pain Management.

Pain is a complex syndrome that is difficult to treat. The increasing numbers of patients living with chronic diseases has led to increasing pain management needs and the rise of opioid use disorder (OUD) as a major and potentially lethal public health concern. Treatment of chronic pain with prescription opioids alone is not always successful, and a multidisciplinary approach is paramount to address the needs of patients at risk of developing or suffering from OUD. Interventional radiologists trained to perform minimally invasive procedures with negligible downtime and postprocedure pain can help stem the tide of opioid-related deaths and disability. This article reviews a wide range of minimally invasive procedures, including vertebral augmentation, sacroplasty, thermal ablation of osseous metastasis, nerve blocks, and gonadal vein embolization, that interventional radiologists are now using successfully to treat chronic pain. The evidence to support use of such procedures is highlighted. This article also briefly discusses emerging techniques such as arterial embolization and ablation for knee and shoulder osteoarthritis that have not yet been fully tested but exhibit strong potential in chronic pain management. By reducing opioid use in patients suffering from chronic pain, these minimally invasive procedures can potentially prevent escalation to OUD.

An analysis of factors associated with increased fluoroscopy time or the need for complex techniques at IVC filter retrieval.

OBJECTIVES: To evaluate factors associated with increased fluoroscopy time or the need for complex techniques at IVC filter retrieval. METHODS: This is a single-institution retrospective cohort study of 187 consecutive patients who underwent IVC filter retrieval. An analysis was performed on associations of patient factors with increased fluoroscopy time and/or the need for complex retrieval techniques. A complex retrieval was defined as one requiring more than standard sheath and snare technique. RESULTS: Access vein during filter placement was not associated with filter tilt at placement or removal (p = 0.61 and 0.48). Neither the direction of the hook nor its relationship to the tilt was associated with the need for complex retrieval or increased retrieval fluoroscopy time (p = 0.25, 0.23, p = 0.18, 0.23). Tilt angle at placement correlated with hook apposition at time of removal (p = 0.01). Hook apposition was associated with complex retrieval and increased fluoroscopy time (p < 0.01). Larger tilt angle at placement was not associated with complex retrieval (p = 0.22), but a larger angle at removal was (p < 0.01). Longer dwell time correlated with the need for complex retrieval (p = 0.02). Filter type, sex, and age were not associated with complex retrievals (p = 0.58, p = 0.90, p = 0.99). CONCLUSION: Contrary to previous hypotheses and studies, access vein for filter placement did not affect filter tilting, and direction of filter hook-tilt relationship did not affect retrieval fluoroscopy time or the need for complex retrieval techniques. Increased filter placement angle was associated with a larger angle at removal and hook-wall apposition, both of which were associated with complex retrievals. KEY POINTS: • Filter hook orientation did not correlate with retrieval complexity. • Filter insertion vein did not correlate with filter tilt. • Filter tilt and hook apposition to the caval wall at the time of retrieval correlated with retrieval procedure complexity.

Hypertrophic Olivary Degeneration: Neurosurgical Perspective and Literature Review.

BACKGROUND: Hypertrophic olivary degeneration (HOD) occurs because of posterior fossa or brainstem lesions that disrupt the dentato-rubro-olivary tract, well known as the Guillain-Mollaret triangle. Clinical and radiologic hallmarks of this condition are palatal myoclonus and T2 hyperintensity of the inferior olivary complex on magnetic resonance imaging (MRI), respectively. Because symptomatic HOD can complicate the recovery of patients with posterior fossa or brainstem lesions, the purpose of this study is to evaluate clinical and imaging findings of patients with HOD. METHODS: Sixteen patients (8 female and 8 male) with a mean age of 40.7 years, (range, 5-83 years) years were included in this study based on clinical symptoms and MRI findings. RESULTS: We reviewed the clinical and imaging findings in 16 cases of HOD at our institution. Seven patients (43.7%) had posterior fossa tumors, 6 patients (37.5%) had cavernoma, 2 patients (12.5%) sustained traumatic brain injury, and only 1 patient (6.2%) had cerebellar infarction. Posterior fossa surgery was performed in 13 (81.2%) of these patients. HOD was detected a mean of 7.2 months (range, 0.5-18 months) after surgery or primary neurologic insult. Unilateral HOD was observed in 10 patients (62.5%), while bilateral HOD was observed in only 6 patients (37.5%). Seven patients (43.7%) were asymptomatic for HOD, whereas 5 patients (31.2%) had symptoms attributable to HOD. Two patients died because of primary tumors, although mean follow-up after detection of HOD on MRI was 52.2 months (range, 1-120 months) in the remaining 14 patients. In these cases, no change in clinical symptoms or imaging findings was detected during follow-up. CONCLUSIONS: In this series, posterior fossa tumors and cavernomas were the most common causes of HOD. Although most of the patients with HOD remained asymptomatic, HOD complicated the course of recovery in almost one quarter of the patients included in this study. Neurosurgeons should be aware of HOD, which has characteristic clinical and imaging findings. In addition, HOD can complicate the recovery of patients with disruption to the dentato-rubro-olivary tract.

Lipopolysaccharide inhibition of glucose production through the Toll-like receptor-4, myeloid differentiation factor 88, and nuclear factor kappa b pathway.

UNLABELLED: Acute exposure to lipopolysaccharide (LPS) can cause hypoglycemia and insulin resistance; the underlying mechanisms, however, are unclear. We set out to determine whether insulin resistance is linked to hypoglycemia through Toll-like receptor-4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor kappaB (NFkappaB), a cell signaling pathway that mediates LPS induction of the proinflammatory cytokine tumor necrosis factor alpha (TNFalpha). LPS induction of hypoglycemia was blocked in TLR4(-/-) and MyD88(-/-) mice but not in TNFalpha(-/-) mice. Both glucose production and glucose utilization were decreased during hypoglycemia. Hypoglycemia was associated with the activation of NFkappaB in the liver. LPS inhibition of glucose production was blocked in hepatocytes isolated from TLR4(-/-) and MyD88(-/-) mice and hepatoma cells expressing an inhibitor of NFkappaB (IkappaB) mutant that interferes with NFkappaB activation. Thus, LPS-induced hypoglycemia was mediated by the inhibition of glucose production from the liver through the TLR4, MyD88, and NFkappaB pathway, independent of LPS-induced TNFalpha. LPS suppression of glucose production was not blocked by pharmacologic inhibition of the insulin signaling intermediate phosphatidylinositol 3-kinase in hepatoma cells. Insulin injection caused a similar reduction of circulating glucose in TLR4(-/-) and TLR4(+/+) mice. These two results suggest that LPS and insulin inhibit glucose production by separate pathways. Recovery from LPS-induced hypoglycemia was linked to glucose intolerance and hyperinsulinemia in TLR4(+/+) mice, but not in TLR4(-/-) mice. CONCLUSION: Insulin resistance is linked to the inhibition of glucose production by the TLR4, MyD88, and NFkappaB pathway.

Do low levels of circulating adiponectin represent a biomarker or just another risk factor for the metabolic syndrome?

The metabolic syndrome is currently defined by various combinations of insulin resistance, obesity, dyslipidaemia and hypertension. The tendency for these risk factors to appear simultaneously suggests a single aetiologic basis. A low level of circulating adiponectin is associated with the appearance of each metabolic syndrome risk factor. The following review summarizes a large body of evidence that suggests a low level of circulating adiponectin represents an independent risk factor and a possible biomarker for the metabolic syndrome. An association between the metabolic syndrome and low adiponectin supports the view that the development of the metabolic syndrome may be triggered by a single underlying mechanism. Clinical studies in the future may show that a low level of circulating adiponectin is a primary biomarker for a specific cluster of metabolic syndrome risk factors rather than all the possible combinations of risk factors currently used to identify the metabolic syndrome. The significance of low circulating adiponectin in risk assessment models should ultimately be compared against insulin resistance, obesity, dyslipidaemia, hypertension and other metabolic syndrome risk factors presently under consideration. Adiponectin can be measured reliably in a clinical setting; circulating values of adiponectin do not fluctuate on a diurnal basis as much as insulin, glucose, triglycerides or cholesterol and only 2-4 microl of blood are currently needed for its measurement.