Francesco Snider

Low-Dose Multidetector CT Angiography in the Evaluation of Infrarenal Aorta and Peripheral Arterial Occlusive Disease

PURPOSE To investigate the ionizing radiation dose, image quality, and diagnostic performance of computed tomographic (CT) angiography of the peripheral arteries with three different CT angiographic acquisition protocols, with use of pretreatment digital subtraction angiography (DSA) as the reference standard. MATERIALS AND METHODS The study was approved by the institutional review board and performed in agreement with the 1990 Declaration of Helsinki and subsequent amendments. Each patient provided informed consent before undergoing CT. The authors performed a prospective, single-center, randomized comparison of three different x-ray exposure CT acquisition protocols in 60 randomized patients with peripheral arterial occlusive disease referred for 64-section multidetector CT angiography of the lower limb (0.625-mm collimation, intravenous administration of 100 mL of iomeprol [400 mg iodine per milliliter] at 4 mL/sec). The acquisition protocols were performed with (a) 120 kVp and a noise index of 26 (moderate noise reduction [MNR]), referred to as the 120-kVp MNR group; (b) 80 kVp and a noise index of 26, referred to as the 80-kVp MNR group; and (c) 80 kVp and a noise index of 30 (high noise reduction [HNR]), referred to as the 80-kVp HNR group. Axial and three-dimensional (3D) images were qualitatively and quantitatively compared by using the overall F test and pairwise comparisons. The X(2) test was used to compare the three protocols in terms of diagnostic performance in patients who also underwent DSA before an interventional procedure. RESULTS Significantly higher attenuation values were obtained in the vessels with the 80-kVp MNR and 80-kVp HNR acquisition protocols. No significant differences were noted in terms of image quality with either axial source images or 3D reconstructions. Likewise, no significant differences were found among the three protocols in terms of noise throughout the peripheral vasculature. Finally, no significant differences were found among the three groups with regard to diagnostic performance. Overall dose reductions of 48% and 61% were obtained for the 80-kVp MNR and 80-kVp HNR protocols, respectively. CONCLUSION Substantial reductions of radiation dose are achievable at multidetector CT angiography of the peripheral arteries without compromising image quality and diagnostic performance if acquisition protocols are modified appropriately and used in conjunction with a contrast material containing a high concentration of iodine.

Neuropsychologic effects of carotid endarterectomy

This study assessed neuropsychologic changes after internal carotid endarterectomy using a design that limited the confounding effects of surgical and anesthesiological stress. Twenty-eight patients (mean age = 65.9 years, SD = 8.4, range 45-79), underwent extensive neuropsychological assessment before and on the seventh day after carotid endarterectomy for symptomatic carotid stenosis greater than 75%. A similarly assessed control group of 30 patients underwent elective orthopaedic surgery. A third cognitive assessment was performed 4 months postoperatively on a subgroup of the study patients. No significant cognitive change occurred in the control group. The study patients showed significant improvement in verbal memory, constructive abilities, verbal attainment, and visual attention; a trend towards further improvement of verbal functions was evident at the late postoperative assessment. No side-specific cognitive change was observed. In conclusion, carotid endarterectomy performed for currently accepted indications significantly improves several cognitive functions.

Assessment of the Genetic Effects of Polymorphisms in the Osteoprotegerin Gene, TNFRSF11B, on Serum Osteoprotegerin Levels and Carotid Plaque Vulnerability

Background and Purpose— Osteoprotegerin (OPG) is a secretory glycoprotein which belongs to the tumor necrosis factor receptor family. Various mechanisms have been suggested by which calcification might alter atherosclerotic plaque stability, but the significance of this intimal calcification is controversial. High concentrations of OPG have been associated with the presence of vascular and cardiovascular diseases. This study was designed to assess the association between gene polymorphisms of the OPG gene (TNFRSF11B), the serum OPG level, and plaque stability in patients with carotid atherosclerosis. Methods— We studied 177 patients with internal carotid artery stenosis who underwent carotid endarterectomy and also 303 controls. Carotid endarterectomy samples removed from patients were assessed by immunohistochemistry. Concentrations of OPG were measured and gene polymorphisms were examined by polymerase chain reaction and restriction enzyme analysis and were compared, initially between patients with carotid atherosclerosis and controls, and subsequently between stable and unstable carotid plaques. Results— We found that the GG genotype of the T245G polymorphism, the CC genotype of the T950C polymorphism, and the CC genotype of the G1181C polymorphism were significantly higher in patients with carotid plaque than in controls (21.5% versus 10.9% , P<0.01; 15.8% versus 7.6%, P<0.01; and 20.3% versus 10.9%, P<0.01, respectively) and that these polymorphisms were associated with high serum OPG levels (4.02 [3.07] versus 2.94 [1.81] pmol/L; P<0.01), which were significantly higher in patients with unstable atherosclerotic plaques (5.86 [4.02] versus 3.53 [1.87] pmol/L; P<0.01). Conclusions— The TNFRSF11B gene polymorphisms studied are associated with high serum OPG levels and might be potential markers for plaque instability.

Surgical management of a uterine leiomyoma extending through the inferior vena cava into the right heart

Abstract We present a case of a 38-year-old woman with intravenous leiomyomatosis originating from the uterus involving the right ventricle, right atrium, inferior vena cava, and iliac veins. Tumors in the heart and the inferior vena cava were removed using cardiopulmonary bypass and circulatory arrest; 10 days after the cardiac operation, hysteroadnexectomy was performed.

Proximal Aneurysmal Neck: Dynamic ECG-gated CT Angiography—Conformational Pulsatile Changes with Possible Consequences for Endograft Sizing

PURPOSE To assess the magnitude of variations in size of the proximal neck of the abdominal aortic aneurysm (AAA) in patients selected to undergo endovascular abdominal aortic aneurysm repair (EVAR) and the potential effect on choice of endograft diameter by using 64-section dynamic electrocardiographically (ECG)-gated computed tomographic (CT) angiography. MATERIALS AND METHODS A prospective single-center study was performed in 40 patients with AAA who underwent both static and dynamic ECG-gated CT angiography. The ethical conduct of the study was approved by the departmental review board, and all patients provided written informed consent. Dynamic ECG-gated data sets were acquired with a low-dose acquisition protocol (100 kV) by using a 0.625-mm-section collimation (40 mL iomeprol [400 mg of iodine per milliliter] versus 80 mL). Pulsatility measurements were taken at suprarenal, juxtarenal, and infrarenal levels within the aneurysmal neck. Manual CT angiographic measurements were performed on modified axial images. On static axial images, one vascular surgeon and one interventional radiologist selected the diameter of the main body of the potential infrarenal stent-graft to implant. The diameter of the main body of the stent-graft selected was compared with the dynamic measurements obtained to calculate the potential relative oversizing performed. RESULTS A total of 40 patients were enrolled. Significant aortic pulsatility was demonstrated within the aneurysmal neck (mean variation, 9.01% ± 4.81 [standard deviation]; absolute change, 1.83 mm ± 1.01; P < .05). When compared with dynamic measurements, the diameter of the endograft selected on the basis of static images would be potentially changed in 12 of 40 (30%) patients. Comparing the minimum or maximum diameter of the aneurysmal neck with the diameter of the endograft selected on the basis of static images, the relative oversizing performed was considered inadequate in seven of 40 (18%) patients. CONCLUSION Dynamic ECG-gated CT may provide information in regard to pulsatile motion that could change the diameter of the endograft selected on the basis of static imaging measurements.

CT Angiography in Stent-Graft Sizing: Impact of Using Inner vs. Outer Wall Measurements of Aortic Neck Diameters

Purpose To assess the impact of using inner wall vs. outer wall measurements on stent-graft sizing for endovascular repair of abdominal aortic aneurysm (AAA). Methods Preoperative static and electrocardiographically-gated 64-slice computed tomographic angiography (CTA) datasets were acquired on 40 consecutive AAA patients (29 men; mean age 78.9±6 years, range 75–89). On static images, the aortic neck diameters were manually measured twice by 2 readers at 3 clinically relevant levels (supra-, juxta-, and infrarenal). The measurements were obtained from intima-to-intima (inner wall) and from adventitia-to-adventitia (outer wall). Dynamically reconstructed scans were also reviewed in each phase of the cardiac cycle to identify inner and outer minimum/maximum diameters. Using inner and outer wall measurements performed on static images, readers selected the size of a stent-graft that required inner neck diameter measurements and then one that required outer wall diameters. To calculate the relative oversizing, each selected stent-graft size was compared to that obtained using dynamic measurements. Oversizing <4% or >30% was considered inadequate. Results Mean variations for the inner and outer wall diameters of 9.75%±4.01% and 8.66%±3.71%, respectively, were recorded on static CTAs; the absolute changes in diameters were 1.82±0.63 mm and 1.91±0.64 mm, respectively. No statistically significant differences were found relative to aortic pulsatility at the 3 levels in the neck for the inner or outer wall diameters. Significant variability was seen between inner (mean 20.8±3.4 mm) vs. outer (mean 23.7±4.3 mm; p<0.05) wall diameters. Stent-graft sizes significantly changed on the basis of the measurement method and device; for example, using the outer diameter to size a stent-graft that requires an inner diameter reference changed 36% of the selected stent-graft sizes, with ∼20% being excessively oversized. Conversely, using the inner diameter to size an outer-diameter–based stent-graft resulted in nearly 40% of the sizes being altered. Based on dynamic measurements, the changes were more dramatic: the oversizing was considered excessive in up to 90% of patients if the measurement method did not match the stent-grafts stipulated reference. Conclusions These data suggest that stent-graft sizing should follow the manufacturers recommendations for using inner or outer diameter references based on dynamic patterns (mean value between diastolic and systolic diameters suggested).

Salmonella aortic aneurysm: Suggestions for diagnosis and therapy based on personal experience - A case report

Infectious aneurysm is a rare event, especially after the introduction of antibiotic therapy. However, its early detection is very important for timely treatment with antibiotics and surgical intervention. This pathology may generally be due to mycotic endocarditis or septic embolization, prevailing in the preantibiotic era, and to aortitis, whose incidence is actually increasing, mainly in subjects with preexisting large-vessel atherosclerosis and intimal defects. This clinical entity is usually defined as microbial arteritis and recognizes Salmonella spp as the microorganism most frequently isolated from blood or vascular tissue cultures. The authors present the case of a 56-year-old man with a history of hypertension that some weeks before admission manifested as hyperpyrexia and episodic lumbar pain, associated with hepatosplenomegaly and with a pulsing mass in the periumbilical region. Abdominal computed tomography (CT) scan documented a voluminous infrarenal aortic aneurysm with a markedly reduced and irregular vessel wall. The patient underwent surgical excision of the aneurysm, during which marked periaortic inflammation phenomena, complete absence of the posterior aortic wall for a length of 5-6 cm, and the exposure of the correspondent vertebral bodies were observed. Histopathologic examination of the aneurysmal tissue showed atheromatous and thrombotic aspects and confirmed strong signs of inflammation. This case may suggest that the occurrence of microbial aortitis, especially from Salmonella spp, should be taken into account in the presence of a septic status associated with back, abdominal, or thoracic pain.

Identification of a potential proinflammatory genetic profile influencing carotid plaque vulnerability

OBJECTIVE Atherosclerosis and vascular remodeling after injury are driven by inflammation and mononuclear cell infiltration. Unstable atherosclerotic plaques are characterized by a large necrotic core. In this study we investigated the distribution and interaction between gene polymorphisms encoding proinflammatory molecules in an Italian population with internal carotid artery stenosis (ICAS). We also evaluated whether reciprocal interaction between these gene polymorphisms increased the risk of plaque vulnerability. METHODS In this genetic association study, 11 proinflammatory gene polymorphisms were analyzed in 933 individuals comprising 344 patients with ICAS who underwent carotid endarterectomy and 589 controls without ultrasound evidence of atherosclerosis or intimal thickening. RESULTS We found that interleukin (IL) 6 (IL-6), IL-1β, monocyte chemoattractant protein-1 (CCL2) macrophage inflammatory protein-1α (CCL3), E-selectin (SELE), intercellular adhesion molecule 1 (ICAM1), and matrix metalloproteinase-3 (MMP-3), and 9 (MMP-9) gene variants were independently and significantly associated with ICAS. The association remained significant even after the Bonferroni correction. We also found a genetic profile associated with different risks for ICAS, depending on the number of high-risk genotypes simultaneously present in an individual. Furthermore, proinflammatory genetic profiles are significantly more common in individuals with unstable carotid plaque. CONCLUSIONS Our study shows, for the first time, a reciprocal interaction between proinflammatory genotypes for the development and progression of ICAS.

Lectin Pathway of Complement Activation Is Associated with Vulnerability of Atherosclerotic Plaques

Inflammatory mechanisms may be involved in atherosclerotic plaque rupture. By using a novel histology-based method to quantify plaque instability here, we assess whether lectin pathway (LP) of complement activation, a major inflammation arm, could represent an index of plaque instability. Plaques from 42 consecutive patients undergoing carotid endarterectomy were stained with hematoxylin-eosin and the lipid core, cholesterol clefts, hemorrhagic content, thickness of tunica media, and intima, including or not infiltration of cellular debris and cholesterol, were determined. The presence of ficolin-1, -2, and -3 and mannose-binding lectin (MBL), LP initiators, was assessed in the plaques by immunofluorescence and in plasma by ELISA. LP activation was assessed in plasma by functional in vitro assays. Patients presenting low stenosis (≤75%) had higher hemorrhagic content than those with high stenosis (>75%), indicating increased erosion. Increased hemorrhagic content and tunica media thickness, as well as decreased lipid core and infiltrated content were associated with vulnerable plaques and therefore used to establish a plaque vulnerability score that allowed to classify patients according to plaque vulnerability. Ficolins and MBL were found both in plaques’ necrotic core and tunica media. Patients with vulnerable plaques showed decreased plasma levels and intraplaque deposition of ficolin-2. Symptomatic patients experiencing a transient ischemic attack had lower plasma levels of ficolin-1. We show that the LP initiators are present within the plaques and their circulating levels change in atherosclerotic patients. In particular, we show that decreased ficolin-2 levels are associated with rupture-prone vulnerable plaques, indicating its potential use as marker for cardiovascular risk assessment in atherosclerotic patients.

Retrievable filter as an unusual cause of abdominal and lower back pain : A report of an exceptional case

Retrievable filter as an unusual cause of abdominal and lower back pain: A report of an exceptional case -