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Background: Significant geographical variations exist in amputation rates and utilization of diagnostic and therapeutic vascular procedures before lower extremity amputations in the United States. The purpose of this study was to evaluate the rates of diagnostic and therapeutic vascular procedures in the year prior to amputation in a contemporary population and correlate with pathological findings of the amputation specimens., Methods: A retrospective analysis was conducted of non-traumatic amputations from 2011 to 2017 at a rural community hospital. We reviewed the proportion of patients undergoing diagnostic (ankle brachial index with duplex ultrasound, computerized tomography angiogram and invasive angiogram) and therapeutic (endovascular and surgical revascularization) vascular procedures in the year prior to amputation. Prevalence of tissue viability and osteomyelitis were evaluated in all amputated specimens and atherosclerotic vascular disease (ASVD) was evaluated in major amputations. We also analyzed primary amputation rates among different subgroups., Results: 698 patients were included with 248 (36%) major amputations and 450 (64%) minor amputations. Any diagnostic procedure was performed in 59% of the major amputations and 49% of the minor amputations (P = 0.01). Any therapeutic revascularization procedure was performed in 34% of the major amputations and 28% of the minor amputations (P = 0.08). The pathology of major amputation specimens revealed severe ASVD in 57% and mild-moderate ASVD in 27% of specimens. Tissue viability was significantly higher in major amputations (90% vs 30%, P = 0.04) and osteomyelitis was significantly higher in minor amputations (50% vs 14%, P = 0.03). Primary amputations were performed in 66% of major amputations, 72% of minor amputations, 81% with mild to moderate ASVD and 54% with severe ASVD., Conclusion: Diagnostic and therapeutic vascular procedures appear under-utilized for patients undergoing lower extremity amputations at a rural community hospital. ASVD rates and tissue viability imply that revascularization could be of significant benefit to avoid major amputation.

Background: The risk assessment profile (RAP) score has been used to determine patients who would most benefit from lower extremity duplex ultrasound screening (LEDUS). We hypothesized that revising our LEDUS protocol to perform screening ultrasound examinations in patients with an RAP ≥8 within 48 h of admission would reduce the number of LEDUS performed without changing outcomes., Methods: A retrospective review was conducted on trauma patients admitted from July 1, 2014, to June 30, 2015, and July 1, 2016, to June 30, 2017. In 2014-2015, patients with an RAP score ≥5 underwent weekly LEDUS examinations starting on hospital day 4. In 2016-2017, the protocol was changed to start screening patients with an RAP score ≥8 by hospital day 2. Both protocols screened with weekly ultrasounds after the first examination. Demographic data, injury characteristics, LEDUS examination findings, chemoprophylaxis type, and venous thromboembolism incidence were collected., Results: A total of 602 patients underwent LEDUS examination in 2014-2015, whereas only 412 underwent LEDUS in 2016-2017. No significant difference was seen in the number of patients diagnosed with deep vein thrombosis (DVT) or pulmonary embolism. DVTs were most often identified on the first LEDUS examination in both cohorts. Of patients diagnosed with a DVT on an LEDUS examination, a significantly higher RAP score (12 versus 10), and a shorter time to first duplex (1 versus 3 d), and DVT diagnosis (2 versus 4 d) were observed in the 2016-2017 cohort. In patients diagnosed with a pulmonary embolism, no significant differences were demonstrated between cohorts., Conclusions: Refinement of LEDUS protocols can decrease overutilization of hospital resources without compromising trauma patient outcomes., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objectives: The placement of inferior vena cava filters (IVCF) continues to rise. Vascular specialists adopt different practices based on local expertise. This study was performed to assess the attitudes of vascular specialists towards the placement and retrieval of IVCF., Methods: An online survey of 28 questions related to practice patterns regarding IVCF was administered to 1429 vascular specialists. Vascular specialists were categorized as low volume if they place less than three IVCF per month and high volume if they place at least three IVCF per month. The responses of high volume and low volume were compared using two-sample t-tests and Chi-square tests., Results: A total of 259 vascular specialists completed the survey (18% response rate). There were 191 vascular surgeons (74%) and 68 interventional radiologists (26%). The majority of responders were in academic practice (67%) and worked in tertiary care centers (73%). The retrievable IVCF of choice was Celect (27%) followed by Denali (20%). Forty-two percent used a temporary IVCF and left it in situ instead of using a permanent IVCF. Eighty-two percent preferred placing the tip of the IVCF at or just below the lowest renal vein. Thirty-one percent obtained a venous duplex of the lower extremities prior to retrieval while 24% did not do any imaging. There were 132 (51%) low volume vascular specialists and 127 (49%) high volume vascular specialists. Compared to low volume vascular specialists, significantly more high volume vascular specialists reported procedural times of less than 30 min for IVCF retrieval (57% vs. 42%, P = 0.026). There was a trend for high volume to have fewer unsuccessful attempts at IVCF retrieval but that did not reach statistical significance ( P = .061). High volume were more likely to have attempted multiple times to retrieve an IVCF (66% vs. 33%, P < .001), and to have used bronchoscopy forceps (32% vs. 14%, P = .001) or a laser sheath (14% vs. 2%, P < .001) for IVCF retrieval. In general, vascular specialists were not comfortable using bronchoscopy forceps (65%) or a laser sheath (82%) for IVCF retrieval., Conclusions: This study underscores significant variability in vascular specialists practice patterns regarding IVCF. More studies and societal guidelines are needed to define best practices.

Background: Early identification of carotid and vertebral artery dissections has been advocated to reduce stroke among trauma patients. We sought to characterize trends in the diagnosis of traumatic carotid and vertebral artery dissections and association changes in stroke rate among Medicare beneficiaries., Methods: Using Medicare claims, we created a cohort of 5,961 beneficiaries admitted with a new traumatic carotid or vertebral artery dissection from 2001 to 2012. We calculated rates of stroke during hospitalization and 90 days of discharge. We calculated rates of carotid imaging using computed tomography-angiography, carotid duplex, and plain angiography index hospitalization. To study concurrent secular trends, we created a secondary cohort of patients admitted after any traumatic injury from 2001 to 2012 and determined rates of stroke and carotid imaging within this cohort., Results: From 2001 to 2012, incidence of traumatic carotid dissection increased 72% among Medicare beneficiaries (1.1-1.76 per 100,000 patients; rate ratio [RR], 1.72; 95% CI, 1.6-1.9, P < 0.001). Among patients diagnosed with traumatic carotid or vertebral artery dissections, the combined in-hospital and 90-day stroke rate did not change significantly (4.9% in 2001; 5.2% in 2012; RR, 1.06; 95% CI, 0.93-1.20; P = 0.094). Likewise, there was little change in mortality (10.3%; RR, 1.01; 95% CI, 0.95-1.06; P = 0.88). Among all trauma patients, the use of computed tomography angiography has increased 16-fold (2-35 per 100,000 patients; RR, 16.7; 95% CI, 13-19; P < 0.0001)., Conclusions: Despite increased diagnosis of carotid or vertebral artery dissection, there has been little change in stroke risk among trauma patients. Efforts to more effectively target imaging and treatment for these patients are necessary., (Published by Elsevier Inc.)

Background: Carotid endarterectomy (CEA) is currently performed by various surgical specialties with varying outcomes. This study analyzes different surgical practice patterns and their effect on perioperative stroke and cost., Methods: This is a retrospective analysis of prospectively collected data of 1000 consecutive CEAs performed at our institution by three different specialties: general surgeons (GS), cardiothoracic surgeons (CTS), and vascular surgeons (VS)., Results: VS did 474 CEAs, CTS did 404, and GS did 122. VS tended to operate more often on symptomatic patients than CTS and GS: 40% vs 23% and 31%, respectively (P < .0001). Preoperative workups were significantly different between specialties: duplex ultrasound (DUS) only in 66%, 30%, and 18%; DUS and computed tomography angiography in 27%, 35%, and 29%; and DUS and magnetic resonance angiography in 6%, 35%, and 52% for VS, CTS, and GS, respectively (P < .001). The mean preoperative carotid stenosis was not significantly different between the specialties. The mean heparin dosage was 5168, 7522, and 5331 units (P = .0001) and protamine was used in 0.2%, 19%, and 8% (P < .0001) for VS, CTS, and GS, respectively. VS more often used postoperative drains; however, no association was found between heparin dosage, protamine, and drain use and postoperative bleeding. Patching was used in 99%, 93%, and 76% (P < .0001) for VS, CTS, and GS, respectively. Bovine pericardial patches were used more often by CTS and ACUSEAL (Gore-Tex; W. L. Gore and Associates, Flagstaff, Ariz) patches were used more often by GS (P < .0001). The perioperative stroke/death rates were 1.3% for VS and 3.1% for CTS and GS combined (P = .055); and were 0.7% for VS and 3% for CTS and GS combined for asymptomatic patients (P < .034). Perioperative stroke rates for patients who had preoperative DUS only were 0.9% vs 3.3% for patients who had extra imaging (computed tomography angiography/magnetic resonance angiography; P = .009); and were 0.9% vs 3% for asymptomatic patients (P = .05). When applying hospital billing charges for preoperative imaging workups (cost of DUS only vs DUS and other imaging), the VS practice pattern would have saved $1180 per CEA over CTS and GS practice patterns; a total savings of $1,180,000 in this series., Conclusions: CEA practice patterns differ between specialties. Although the cost was higher for non-VS practices, the perioperative stroke/death rate was somewhat higher. Therefore, educating physicians who perform CEAs on cost-saving measures may be appropriate., (Copyright © 2014 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: The value and cost-effectiveness of less invasive alternative imaging (AI) modalities (duplex ultrasound scanning, computed tomography angiography, and magnetic resonance angiography) in the care of peripheral arterial disease (PAD) has been reported; however, there is no consensus on their role. We hypothesized that AI utilization is low compared with angiography in the United States and that patient and hospital characteristics are both associated with AI utilization., Methods: The Nationwide Inpatient Sample (2007-2010) was used to identify patients with an International Classification of Diseases-Ninth Edition diagnosis of claudication or critical limb ischemia (CLI) as well as PAD treatment (surgical, endovascular, or amputation). Patients with AI and those with angiography or expected angiography (endovascular procedures without imaging codes) were selected and compared. Multivariable logistic regression was performed for receiving AI stratified by claudication and CLI and adjusting for patient and hospital factors., Results: We identified 290,184 PAD patients, of whom 5702 (2.0%) received AI. Patients with AI were more likely to have diagnosis of CLI (78.8% vs 48.6%; P < .0001) and receive open revascularizations (30.4% vs 18.8%; P < .0001). Van Walraven comorbidity scores (mean [standard error] 5.85 ± 0.22 vs 4.10 ± 0.05; P < .0001) reflected a higher comorbidity burden in AI patients. In multivariable analysis for claudicant patients, AI was associated with large bed size (odds ratio [OR], 3.26, 95% confidence interval [CI], 1.16-9.18; P = .025), teaching hospitals (OR, 1.97; 95% CI, 1.10-3.52; P = .023), and renal failure (OR, 1.52; 95% CI, 1.13-2.05; P = .006). For CLI patients, AI was associated with black race (OR, 1.53; 95% CI, 1.13-2.08; P = .006) and chronic heart failure (OR, 1.29; 95% CI, 1.04-1.60; P = .021) and was negatively associated with renal failure (OR, 0.80; 95% CI, 0.67-0.95; P = .012). The Northeast and West regions were associated with higher odds of AI in claudicant patients (OR, 2.41; 95% CI, 1.23-4.75; P = .011; and OR, 2.59; 95% CI, 1.34-5.02; P = .005, respectively) and CLI patients (OR, 4.31; 95% CI, 2.20-8.36; P < .0001; and OR, 2.18; 95% CI, 1.12-4.22; P = .021, respectively). Rates of AI utilization across states were not evenly distributed but showed great variability, with ranges from 0.31% to 9.81%., Conclusions: National utilization of AI for PAD is low and shows great variation among institutions in the United States. Patient and hospital factors are both associated with receiving AI in PAD care, and AI utilization is subject to significant regional variation. These findings suggest differences in systems of care or practice patterns and call for a clearer understanding and a more unified approach to imaging strategies in PAD care., (Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Background: Surveillance is considered mandatory after endovascular repair (EVR), but its impact on imaging services remains unreported. This study reports the effect of EVR surveillance on imaging resources., Methods: A single-center's duplex database was interrogated from January 1, 2004 to January 1, 2012. All examinations requested by a vascular surgeon were reported, including preoperative abdominal aortic aneurysms, surveillance after EVR, lower limb arterial and venous duplex, and arteriovenous fistulae., Results: A total of 24 309 patients underwent duplex. The EVR surveillance increased from 192 scans in 2004 to 1325 scans in 2011, 9.5% (192 of 2030) and 34.4% (1325 of 3850) of each year's examinations. By 2011, EVR surveillance was the most common indication for duplex., Conclusion: Lifelong EVR surveillance creates a rapidly increasing workload for imaging services. Further research should aim to reduce the burden of EVR surveillance. Targeting surveillance to the minority of patients at greatest risk of endograft failure might optimize the usage of imaging resources.

Peripheral arterial disease is usually secondary to stenotic or occlusive atherosclerosis and is both common and increasing in western society. The majority of symptomatic patients have intermittent claudication and only a minority (<2% and typically those with diabetes mellitus or renal failure) progress to critical limb ischaemia, heralded by the onset of rest pain and/or tissue loss. Imaging is largely reserved for patients with disabling symptoms in whom revascularisation is planned. In these patients, accurate depiction of the vascular anatomy is critical for clinical decision making as the distribution and severity of disease are key factors determining whether revascularisation should be by endovascular techniques or open surgery. Driven by advances in technology, non-invasive vascular imaging has recently undergone significant refinement and has replaced conventional digital subtraction angiography for many clinical indications. In this review, the relative merits and limitations of duplex ultrasound, CT angiography, and magnetic resonance angiography are discussed, emerging imaging techniques are described, and complications relating to the use of intravascular contrast agents are highlighted.

Stenoses and occlusions of the anterior, middle, pre- and postcommunicating posterior cerebral, and basilar and intracranial vertebral arteries are reliably detected by transcranial Doppler (TCD) and transcranial color duplex sonography (TCCS). Diagnosis of carotid siphon stenosis is consistently obtained by transorbital Doppler sonography. Internationally accepted criteria for diagnosing intracranial arterial obstructions are lacking. Both TCD and TCCS reliably identify collateral flow through the anterior and posterior communicating arteries. It is unclear whether TCCS is more accurate than TCD for detecting intracranial obstructions and collaterals, as no study has examined this issue.

This chapter summarizes the diagnostic criteria and reliability of ultrasound detection of intracranial dural arteriovenous fistulae (DAVF), carotid-cavernous fistulae (CCF), and paragangliomas. In arteries feeding DAVF ultrasound shows increased blood flow, systolic and, especially, end-diastolic velocities causing a decreased resistance index (RI), and an increased diameter. The RI of the external carotid artery (ECA; cutoff: right, 0.72; left, 0.71) yielded a sensitivity of 74%, a specificity of 89%, a positive predictive value of 79%, and a negative predictive value of 86%, for detecting DAVF. Preliminary data suggest that contrastenhanced transtemporal color duplex sonography (CDS) may be useful for screening patients with clinical suspicion of DAVF of the transverse/sigmoid sinus. Most patients with CCF show a dilated superior ophthalmic vein with reversed blood flow direction. Decreased RI and increased blood flow and flow velocities are found in internal carotid arteries supplying the cavernous sinus directly through a fistula (type A CCF) at extracranial CDS, and sometimes in the cavernous sinus of CCF at transtemporal CDS. Definite diagnosis of DAVF and CCF is performed with catheter angiography. Typical CDS findings observed in paragangliomas of the head and neck include their solid, well-defined, and hypoechoic appearance, hypervascularity, intratumoral flow direction, displacement of the internal carotid artery (ICA) and ECA as well as the internal jugular vein. Whereas carotid body tumors can be visualized completely in most patients, other paragangliomas, for example, of the vagal nerve, are at best partially depicted due to their location in the upper neck. Confirmation of ultrasound suspicion of paraganglioma by magnetic resonance imaging or computed tomography of the neck is mandatory.

Objectives: Duplex ultrasound mapping of arm veins is being performed with increasing frequency. Unlike ultrasound testing in other areas, this has never been subjected to a gold standard invasive test to determine accuracy. Duplex mapping appears to have a good predictive value whenever large veins are demonstrated preoperatively, but its ability to accurately measure minimum-sized veins is unproven. In this study, we compared diameter measurements obtained under six different conditions and used the maximum diameter as the comparison gold standard., Methods: A 12-MHz linear probe was used to measure the cephalic and basilic vein cross-sectional diameters at the wrist level in 24 normal volunteers under the following conditions: (1) resting supine with a room temperature of 23 degrees to 24 degrees C, (2) supine with a tourniquet inflated to 65 mm Hg, (3) sitting with the arm dangling, (4) sitting with a tourniquet, (5) sitting after a 2-minute immersion in warm water (44 degrees C), and (6) same with tourniquet. Half the subjects underwent the protocol in a different order., Results: Vein diameters were significantly larger after submersion in warm water compared with supine (P < .05, pair-wise multiple comparison procedure, Student-Newman-Keuls method). Assuming the sitting position (from supine) resulted in a decreased arm vein diameter 58% of the time. In 25% of the normal subjects, the cephalic vein size was <2 mm, which increased to >2 mm after warming. All subjects had either a cephalic or a basilic vein at the wrist that was >3.1 mm after warming., Conclusion: Use of warm water immersion before vein diameter measurement in a sitting position, without a tourniquet, will result in significantly larger diameter findings in normal arm veins. These diameters are likely to more closely resemble the venous diameter after distension with arterial pressure. Further studies are needed to see if warming in patients could result in increased utilization of autogenous arm vein for dialysis access and bypass.

Renal artery stenosis is the most common cause of potentially remediable secondary hypertension. The most common causes include atherosclerosis and fibromuscular dysplasia. Particularly the atherosclerotic form is a progressive disease that may lead to gradual and silent loss of renal functional tissue. Thus, early diagnosis of renal artery stenosis is an important clinical objective since interventional therapy may improve or cure hypertension and preserve renal function. Screening for renal artery stenosis is indicated in the suspicion of renovascular hypertension or ischemic nephropathy in order to identify patients in which an endoluminal or a surgical revascularization is advisable. In the recent years many noninvasive tests have been proposed and evaluated in the clinical practice, in alternative to arteriography. These include nuclear scan, color Doppler sonography, CT angiography and MR angiography. Sonography is usually the first diagnostic modality for the non invasive evaluation of renal vascular disease with 95% sensitivity and 90% specificity when performed in dedicated laboratories. Despite sonography is highly affected by operator dependence, and it takes a lot of time to train good operators, actually is the best screening test because it is not expensive, non invasive and accurate. When a discrepancy exists between the clinical data and the results of US, other tests are mandatory.

Purpose: This study compares the ability of computer-derived B-mode ultrasound gray-scale measurements from a single longitudinal view (SLV) versus multiple cross-sectional views (MCSV) to differentiate symptomatic from asymptomatic carotid plaque causing more than 70% stenosis., Method: Seventy-four internal carotid artery (ICA) stenoses (70%-99%; 33 asymptomatic, 41 symptomatic within 3 months) were imaged to obtain the "best" SLV and five to eight MCSV images at 5 mm intervals from the carotid bifurcation. Digitized sonograms were computerized and normalized to the gray scale median (GSM) of blood (0) and vessel adventitia (200). Plaque GSM was determined for each frame (image analysis, MATLAB 5.3). General risk factors for stroke and plaque echogenicity (SLV GSM; minimum MCSV GSM; cross-sectional axial heterogeneity (highest minus lowest MCSV GSM) were determined for each group., Results: Risk factors for stroke were similar in both groups, as was mean SLV GSM: symptomatic, 34 (95% confidence interval [CI], 24.8-43.0), asymptomatic, 43 (CI, 32.6-53.2); P =.1. Minimum MCSV GSM was lower for symptomatic plaque: 7 (CI, 4.2-9.8] vs 18.3 (CI, 12.2-24.5); P =.002. Greater axial GSM heterogeneity was present in symptomatic plaque: 34.5 (CI, 27.2-41.9) vs 16 (CI, 11.0-20.8); P =.0001., Conclusions: MCSV cross-sectional imaging that enables objective assessment of regional plaque echolucency and heterogeneity is more sensitive than SLV sonography for differentiating symptomatic from asymptomatic plaque.

Background: Catheterizations and endovascular procedures in which the femoral artery is cannulated are sometimes complicated by iatrogenic pseudoaneuryms. Surgical repair of pseudoaneurysms was the treatment of choice until 1991 when compression was used in those that were small. A less uncomfortable technique involving the ultrasound scan-guided injection of thrombin (UGTI) has been used more recently. The purpose of this study was to prospectively evaluate the effectiveness of ultrasound scan-guided thrombin injection (UGTI) as a treatment of iatrogenic femoral pseudoaneurysms., Methods: From December 1998 to December 2000, 3734 femoral artery catheterizations were performed, and from those, 32 consecutive patients with 33 femoral pseudoaneurysms (0.88%) of less than 8 cm were prospectively enrolled for UGTI. With sterile technique, a 21-gauge or 22-gauge spinal needle was used to access the pseudoaneurysm and thrombin (100 to 6000 international units [IU]) was slowly injected until thrombosis occurred., Results: The initial success rate was 100%. Thirty-one cases (93.9%) remained successfully thrombosed with a single injection at day 30. Recurrence of two pseudoaneurysms (6.1%) was seen at day 1 and day 8. One patient had groin cellulitis develop, and the other had a bleed into the thigh after discharge; both were treated with open surgical repair. Fifteen patients underwent UGTI on an outpatient basis with 100% successful ablation. More than half of the patients were on an inpatient basis (53.1%). Hospital stay was 1 to 9 days, with 88.2% of the patients released on day 1 or 2. However, two patients had a prolonged stay: one from open repair (day 9) and the other from a gastrointestinal bleed (day 8). Pseudoaneurysms ranged from 1.7 to 7.5 cm and lasted 1 to 17 days before UGTI. Twenty-one of the patients (65.7%) continued undergoing anticoagulant therapy at the time of injection. Ten of the last 11 cases needed less than 800 IU, and nearly half of the pseudoaneurysms (49%) successfully thrombosed with less than 600 IU. No procedural complications or mortality were noted. No statistical significance was found between occurrence of the pseudoaneurysm and sheath size (with chi(2) test, P value =.05) or between the size of the pseudoaneurysm and successful thrombosis (with chi(2) test: degrees of freedom, 6 - 1 = 5; P value =.227426). A mean follow-up period of 11.8 months was documented (range, 71 to 24 months). Seven patients were lost to follow-up at less than 30 days., Conclusion: Percutaneous thrombin injection of iatrogenic pseudoaneurysms is an effective treatment. Not only is it minimally painful, but it can be done as an outpatient procedure and anticoagulation therapy does not hinder the success. Minimal thrombin seems necessary to successfully treat pseudoaneurysms that may further limit procedure-related complications.

Recent advances in ultrasound technology has led to the development of high resolution transducers, typically 7 to 10 MHZ, with grey-scale, pulsed wave duplex Doppler, colour Doppler and even power Doppler capabilities. Computed tomography, scintigraphy and magnetic resonance may be used to image the testis, but ultrasound is the most sensitive imaging modality available for demonstration of scrotal contents. Ultrasound has the additional advantages that it is relatively cheap and widely available, and does not involve the use of ionizing radiation. Real time grey-scale ultrasound provides good cross-sectional images, whilst pulsed Doppler and colour Doppler ultrasound provide quantitative and directional information on vascular flow within the testis. We have presented a pictorial review of normal findings encountered in sonographic imaging of several testes, as well as anatomical variants, and emphasized the importance of their recognition using various ultrasound techniques. We have also briefly reviewed ways of optimizing the images obtained from ultrasound scanners.

The role of ultrasound in the diagnosis of cerebrovascular disease is reviewed and is compared with other existing vascular imaging modalities. The present and future role of neurosonology is discussed including transcranial Doppler and carotid Doppler duplex ultrasound.