Estimation and clinical verification of the effective and skin doses for pediatric and adult patients undergoing the cardiac interventional examination using five PMMA phantoms and TLD/ionization chamber technique.

BACKGROUND: Effective and skin doses gain much attention since the cardiac catheterization laboratory (CCL) is a place where both patients and medical staff are exposed to X-ray or fluoroscopy environment and gain a cumulative dose during the cardiac interventional procedure. OBJECTIVE: These doses for pediatric and adult patients undergone cardiac interventional examination using five PMMA phantoms and thermoluminescence dosimeter (TLD)/ionization chamber technique were estimated in this work with the further clinical verification. METHODS: Five PMMA phantoms (10, 30, 50, 70, and 90 kg) were customized to represent baby, child, adult female, adult male, and overweight adult (by Asian complexion standards), respectively, in accordance with the ICRU-48 report. Each phantom could be disassembled into 31 plates to insert TLD chips for measuring X-ray exposed dose or assisted with an auxiliary plate to insert high-sensitivity ionization chamber for surveying low-energy fluoroscopy dose. RESULTS: The data acquired from five phantoms were integrated into four semi-empirical formulas, in order to fit the binary quadratic form "Dose = A⋅BMI2+B⋅DAP2+C⋅BMI+ D⋅DAP+E". The latter linked the X-ray and fluoroscopy effective/skin doses, respectively, with a high coefficient of determination R2(from 0.888 to 0.986). CONCLUSIONS: The model refinement with DAP share adjustment is envisaged.

Different Mid-Term Prognostic Predictors of Major Adverse Events in Diabetic and Nondiabetic Peripheral Artery Disease Presenting With Critical Limb Ischemia.

We compared midterm prognostic predictors of peripheral artery disease (PAD) with or without diabetes mellitus (DM) presenting with critical lower limb ischemia (CLI). A total of 172 patients with PAD (109 DM; 63 non-DM) were enrolled. The major adverse events (MAEs) were death or amputation. The diabetic group had a higher MAE rate (39% vs 22%, P = .042) with a mean follow-up duration of 30 ± 19 months. In a multivariate binary logistic regression analysis, revascularization (odds ratio = 0.289, P = .006) and higher serum cholesterol (odds ratio=0.988, P = .027) predicted a lower MAE rate in the DM group. In contrast, the presence of severe chronic kidney disease (stage 4 or 5, odds ratio = 5.238, P = .025) was a positive predictor of MAEs in the nondiabetic group. In conclusion, the prognostic predictors of MAE in diabetic and nondiabetic patients with PAD and CLI were different.

Axillofemoral bypass relieves visceral malperfusion in type B aortic dissection.

A 58-year-old man with acute type B aortic dissection presented with right lower limb cyanosis, mesenteric ischemia, and acute renal failure. He was treated with extraanatomic right axillofemoral bypass surgery alone, recovered completely from renal, mesenteric, and lower extremity malperfusion shortly thereafter, and lived free of symptoms for the following year. Follow-up computed tomography angiograms documented adequate expansion of the true aortic lumen and good perfusion of visceral organs. Thus, managing such patients with coexisting visceral and extremity malperfusion may be accomplished with axillofemoral bypass exclusively, which can relieve ischemia of upstream abdominal organs and downstream lower extremities effectively and durably.