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1.
J Wound Care ; 33(Sup3): S51-S58, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38457307

ABSTRACT

DECLARATION OF INTEREST: The authors have no conflicts of interest to declare.


Subject(s)
Polyurethanes , Wound Healing , Humans
2.
PLoS One ; 19(2): e0297618, 2024.
Article in English | MEDLINE | ID: mdl-38422111

ABSTRACT

Microindentation of fresh biological tissues is necessary for the creation of 3D biomimetic models that accurately represent the native extracellular matrix microenvironment. However, tissue must first be precisely sectioned into slices. Challenges exist in the preparation of fresh tissue slices, as they can tear easily and must be processed rapidly in order to mitigate tissue degradation. In this study, we propose an optimised mounting condition for microindentation and demonstrate that embedding tissue in a mixture of 2.5% agarose and 1.5% gelatin is the most favourable method of tissue slice mounting for microindentation. This protocol allows for rapid processing of fresh biological tissue and is applicable to a variety of tissue types.


Subject(s)
Biomimetics , Extracellular Matrix , Food , Gelatin , Histocompatibility Testing
3.
J Endovasc Ther ; : 15266028241231171, 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38388373

ABSTRACT

OBJECTIVES: Comparative effectiveness of fenestrated endovascular aneurysm repair (FEVAR) and chimney graft endovascular aneurysm repair (ChEVAR) for juxtarenal aortic aneurysms (JAAs) remains unclear. Our objective was to identify and analyze the current body of evidence comparing the effectiveness of both techniques for JAA. METHODS: We performed a systematic review and meta-analysis comparing the effectiveness of FEVAR and ChEVAR for JAA repair. We searched MEDLINE, EMBASE, and Cochrane Register for Controlled Trials from January 1, 1990, for randomized and non-randomized studies assessing outcomes of FEVAR and ChEVAR for JAA repair. Screening, data extraction, risk of bias assessment, and GRADE (Grading of Recommendations, Assessments, Development, and Evaluations) certainty of evidence were performed in duplicate. Data were pooled statistically where possible. RESULTS: Nine retrospective cohort studies comparing the use of FEVAR and ChEVAR for juxtarenal aneurysm were included for meta-analysis. The FEVAR and ChEVAR arms of the meta-analysis consisted of 726 participants and 518 participants, respectively. There were 598 (86.8%) and 332 (81.6%) men in each arm. The mean diameter was larger in the ChEVAR arm (59 mm vs 52.5 mm). Both techniques had similar rates of postoperative 30-day mortality, 3.38% (8/237) versus 3.52% (8/227), acute kidney injury, 16.76% (31/185) versus 17.31% (18/104), and major adverse cardiac events, 7.30% (46/630) versus 6.60% (22/333). The meta-analysis supported the use of FEVAR for most outcomes, with significant advantage for technical success (odds ratio [OR]: 3.24, 95% CI: 1.24-8.42) and avoidance of type 1 endoleak (OR: 5.76, 95% CI: 1.94-17.08), but a disadvantage for spinal cord ischemia (OR: 10.21, 95% CI: 1.21-86.11), which had a very low number of events. The quality of evidence was "moderate" for most outcomes. CONCLUSION: Both endovascular techniques had good safety profiles. The evidence does not support superiority of either FEVAR or ChEVAR for JAA. CLINICAL IMPACT: While lack of equipoise has hampered the design of randomised trials of open versus endovascular repair of juxtarenal aortic aneurysms, concern about the durability of endovascular repair highlights the need for stronger evidence of the comparative efficacy of endovascular techniques. This review performed meta-analysis and evidence appraisal of recent data from large observational studies comparing fenestrated and chimney techniques, using a comprehensive outcome set. Superiority of either intervention could not be established due to differences in participants' baseline risk in each study arm. However, data suggests that both techniques are safe and suitable for use when indicated.

4.
J Vasc Surg ; 78(1): 158-165, 2023 07.
Article in English | MEDLINE | ID: mdl-36918105

ABSTRACT

OBJECTIVE: The aim of the study is to evaluate the natural history of extracranial cervical artery dissection (CAD) including comorbidities, symptoms at presentation, recurrence of symptoms, and long-term outcome following different treatment approaches. METHODS: A retrospective review of patients treated for acute CAD was performed over a 5-year period from January 2017 to April 2022. RESULTS: Thirty-nine patients were included in the study, 25 (64.1%) with acute internal carotid artery dissection and 14 (35.9%) with acute vertebral artery dissection. Thirty-four patients (87.1%) had spontaneous CAD, and five patients (12.8%) had traumatic CAD. The mean age of the cohort was 54.2 years. The mean time from symptom onset to presentation was 4.34 days. The most common symptoms in internal carotid artery dissection were unilateral weakness (44%), headache (44%), slurred speech (36%), facial droop (28%), unilateral paraesthesia (24%), neck pain (12%), visual disturbance (8%), and Horner's syndrome (8%). The most common symptoms in vertebral artery dissection were headache (35.7%), neck pain (35.7%), vertigo (28.57%), ataxia (14.28%), and slurred speech (14.28%). The imaging modalities used for diagnosis included computed tomography angiography (48.7%), magnetic resonance angiography (41%), and duplex ultrasound (10.2%). In patients with carotid artery dissection, 57% had severe stenosis, 24% had moderate stenosis, and 20% had mild stenosis. All patients treated were managed conservatively with either anticoagulation or antiplatelets. Long-term clinical follow-up was available for 33 patients (84.6%). Thirty patients (90.9%) reported complete resolution of symptoms, and three patients (9%) reported persistent symptoms. Anatomic follow-up with imaging was available for 17 patients (43.58%). Thirteen patients (76.47%) had complete resolution of dissection, two patients (11.76%) had partial resolution of dissection, and two patients (11.76%) had persistent dissection. There was one death unrelated to CAD in a multi-trauma patient. There were four early recurrent symptoms in the first 3 to 8 weeks post discharge. The mean follow-up time was 308.27 days. CONCLUSIONS: The majority of CADs can be managed conservatively with good clinical and anatomical outcome and low rates of recurrence.


Subject(s)
Carotid Artery, Internal, Dissection , Cerebrovascular Disorders , Vertebral Artery Dissection , Humans , Middle Aged , Carotid Artery, Internal, Dissection/complications , Carotid Artery, Internal, Dissection/diagnostic imaging , Carotid Artery, Internal, Dissection/therapy , Vertebral Artery Dissection/complications , Vertebral Artery Dissection/diagnostic imaging , Vertebral Artery Dissection/therapy , Neck Pain/etiology , Constriction, Pathologic , Aftercare , Patient Discharge , Magnetic Resonance Angiography , Headache , Arteries/pathology
5.
J Wound Care ; 31(2): 186-192, 2022 Feb 02.
Article in English | MEDLINE | ID: mdl-35148629

ABSTRACT

OBJECTIVE: Pseudomonas aeruginosa is a Gram-negative bacillus that commonly colonises lower limb venous ulcers. Its effects on venous ulcer healing are widely debated. It produces exotoxins and elastase, as well as forming biofilms in hard-to-heal wounds. It is postulated that these virulence factors lead to slower healing times in patients with lower limb venous ulcers colonised with Pseudomonas. This review aimed to summarise the available evidence pertaining to this topic. METHOD: A systematic review was performed in August 2019, where the Pubmed, Cochrane and Embase databases were searched for relevant literature according to PRISMA guidelines. Retrospective and prospective studies examining the effect of Pseudomonas colonisation on any measure of ulcer healing were included. RESULTS: Some 282 articles were screened, of which seven studies including 491 patients were ultimately included for analysis. Of these, no study demonstrated a significant association between Pseudomonas colonisation and delayed healing of venous ulcers. In five of the seven studies, the effect of Pseudomonas aeruginosa on initial ulcer size at presentation was recorded. CONCLUSION: All the studies demonstrated an association between ulcer size and the presence of Pseudomonas aeruginosa. While Pseudomonas aeruginosa may colonise larger ulcers or those with a worse prognosis, no evidence was found to support the hypothesis that this colonisation had a negative impact on lower limb venous ulcer healing.


Subject(s)
Varicose Ulcer , Humans , Lower Extremity , Prospective Studies , Pseudomonas aeruginosa , Retrospective Studies , Ulcer
6.
EJVES Vasc Forum ; 54: 13-20, 2022.
Article in English | MEDLINE | ID: mdl-34977837

ABSTRACT

OBJECTIVE: Previous studies have demonstrated amputation and mortality rates to be 14.3% - 30% and 11.4% - 28.9%, respectively, for all patients presenting with acute limb ischaemia (ALI). Rates of ALI are higher in patients with malignancy than in those without. Despite this, there remains uncertainty with regards to the most appropriate management for patients with cancer presenting with ALI. This is because of previously published high rates of associated morbidity and mortality in this population. The aim of this review was to summarise the available evidence reporting on outcomes of ALI in patients with underlying malignancy. METHOD: A systematic review was performed in August 2020 in accordance with the PRISMA guidelines. The Medline, Scopus, Cochrane, and Embase databases were searched with the following search string ((acute limb ischaemia) OR (acute limb ischemia)) AND ((cancer) OR (malignancy)). A total of 849 papers were identified and reviewed; six studies were included. Studies were assessed for bias using the National Institute of Health/National Heart, Lung and Blood Institute Quality Assessment Tool. Data including demographics, Rutherford classification, baseline performance scores, method of revascularisation, and peri-procedural outcomes were extracted and analysed. Data were pooled based on outcomes of interest and pooled prevalence was reported with 95% confidence intervals (CI). RESULTS: Six studies with 284 patients with cancer were included for analysis. The pooled overall risk of amputation was 15% (95% CI 5.9 - 26.9). The pooled 30 day mortality rate was 24% (95% CI 14.7 - 34.6). CONCLUSION: Despite limitations of interstudy selection bias and some clinical heterogeneity, the included studies demonstrated acceptable short and medium term outcomes for patients with cancer undergoing revascularisation for acute limb ischaemia. This is in line with current recommendations that patients with underlying malignancy should be considered strongly for revascularisation.

7.
Case Rep Vasc Med ; 2022: 5489653, 2022.
Article in English | MEDLINE | ID: mdl-35036021

ABSTRACT

A 47-year-old female presented to the emergency department with new episodes of hematemesis. She had a background of unresectable T4b + N1 + M0 esophageal squamous cell carcinoma. Contrast CT thoracic aorta diagnosed a ruptured mycotic aortic pseudoaneurysm of the descending aorta, forming a life threating aorto-esophageal fistula secondary to neoplasm. Due to the high risk of fatal haemorrhage, she underwent successful emergency thoracic endovascular aortic repair (TEVAR). Mycotic aortic pseudoaneurysms are a rare and often fatal complication of esophageal carcinomas. They represent a small subsection of aorto-esophageal fistulas. Early diagnosis with cross sectional imaging and vascular control of the sentinel bleed is essential for survival. TEVAR may be used as a bridge to palliative treatment in the case of unresectable esophageal carcinoma.

9.
J Vasc Surg Cases Innov Tech ; 7(1): 26-29, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33665527

ABSTRACT

Endoleaks are a frequent indication for reintervention after endovascular repair of an abdominal aortic aneurysm. Here we present a method of open repair of a persistent type II endoleak involving graft component separation and reconstruction, in a patient with symptomatic interval aneurysmal sac enlargement despite endovascular coiling and embolization. This case report demonstrates an alternative open technique of endograft component separation and reconstruction that may be required in cases where open repair with sac exploration and vessel oversewing is hindered by the graft position.

10.
Ir J Med Sci ; 190(1): 291-296, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32683604

ABSTRACT

INTRODUCTION: Communication is key to any successful relationship with the patient-physician partnership being no different. Recent advances in technology have provided us with an array of new communication tools such as the mobile phone, computer, internet, and email. This new technology has revolutionized communications; however, limitations to their widespread use include access, literacy, and willingness for both the physician and patient to change. METHODS: To gather international data, questionnaires were completed by patients attending vascular surgery outpatient clinics in hospitals in Ireland and Canada. RESULTS: Five hundred ninety-seven patients participated in the study. Of the participants, 83.2% were over 50 years old. The mean age was 63.1 years, with a range of 18-95 years. Overall, home phone call was the most preferred method of communication with 41.0% of patients selecting this option. Of the patients, 82.4% had a mobile phone but just 48.5% use text message. In those over the age of 70, 72.1% use a mobile phone and just 25.3% use text message. Of the participants, 64.1% had access to a computer, and 67.2% had access to the internet with a decline in the usage of both with increasing age. DISCUSSION: Within this patient population, the use of technologies decreases with increasing age of the patients. This demonstrates a large population of service users who are contented with conventional methods of communication. Change within healthcare ICT is inevitable, and therefore, these patients need to be guided and educated to allow a smooth transition from the old to the new.


Subject(s)
Telemedicine/methods , Vascular Surgical Procedures/methods , Adolescent , Adult , Aged , Aged, 80 and over , Communication , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Young Adult
11.
J Vasc Surg Cases Innov Tech ; 6(4): 703-706, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32904943

ABSTRACT

The COVID-19 pandemic is disrupting the provision of acute vascular surgery across the globe. Limited evidence of the impact of nosocomial infection on patient outcomes as well as concerns about critical care capacity will likely have an impact on surgical decision-making. Endovascular therapy offers a way by which perioperative risk can be reduced for vascular patients while also reducing the impact of acute surgery on intensive care unit capacity. This case report describes the management of a patient with complex aortoiliac occlusive disease by a hybrid endovascular approach in light of these constraints, with a successful outcome.

12.
Stroke ; 51(9): e250-e253, 2020 09.
Article in English | MEDLINE | ID: mdl-32755345

ABSTRACT

BACKGROUND AND PURPOSE: The purpose of this study is to examine the ability of ex vivo derived Agatston, Volume, and Density-Volume calcium scores or calcium density measurements to differentiate between carotid plaques based on preoperative cerebrovascular symptomatology. METHODS: Thirty-eight carotid plaques were acquired from standard endarterectomy. Micro-computed tomography was performed on the ex vivo samples. Image series were downsampled to represent the resolution of clinical multidetector computed tomography. Agatston, Volume, and Density-Volume carotid calcium scores were then calculated using coronary methodologies. The fractions of low- and high-density calcification were also determined. RESULTS: The coronary calcium scores could not differentiate between carotid plaques from asymptomatic versus symptomatic patients. However, plaques from asymptomatic patients contained significantly lower fractions of low-density calcification and higher fractions of high-density calcification. CONCLUSIONS: Screening for carotid calcium density in noncontrast computed tomography could reflect plaque stability.


Subject(s)
Calcinosis/diagnostic imaging , Carotid Artery Diseases/diagnostic imaging , Cerebrovascular Disorders/diagnostic imaging , Aged , Aged, 80 and over , Calcinosis/complications , Calcium/blood , Carotid Artery Diseases/complications , Carotid Stenosis/complications , Carotid Stenosis/diagnostic imaging , Carotid Stenosis/surgery , Cerebrovascular Disorders/etiology , Endarterectomy, Carotid , Female , Humans , Male , Middle Aged , Multidetector Computed Tomography , Plaque, Atherosclerotic , X-Ray Microtomography
13.
J Cardiovasc Comput Tomogr ; 14(1): 20-26, 2020.
Article in English | MEDLINE | ID: mdl-31303579

ABSTRACT

BACKGROUND: The Agatston Calcium Score is a predictor of major adverse cardiovascular events but it is unable to identify high-risk lesions. Recent research suggests that examining calcification phenotype could be more indicative of plaque stability. OBJECTIVE: To examine the Agatston score's ability to determine atherosclerotic calcification phenotype. METHODS: Micro-Computed Tomography was performed on 20 carotid and 20 peripheral lower limb lesions. ImageJ pixel histogram analysis quantified the non-calcified (≥30HU, <130HU) and calcified (≥130HU) tissue volumes. ImageJ '3D Objects Counter' plugin determined the calcified particle count, volumes and maximum attenuation density of each particle. Image stacks were subsequently downsampled to a resolution of 0.7 × 0.7 × 3 mm and an approximation for the Extra-Coronary Calcium Scores (ECCS) were calculated. Spearman's correlation examined the relationships between ECCS approximations and calcification parameters. RESULTS: ECCS has a strong positive correlation with the Calcified Volume Fraction (CVF) (rs = 0.865, p < 0.0005), weak positive correlations with Calcified Particle Fraction (CPF) (rs = 0.422, p = 0.007) and Microcalcification Fraction (micro-CF) (rs = 0.361, p = 0.022). There is no correlation evident between ECCS and Calcified Particle Index (CPI) (rs = -0.162, p = 0.318). It is apparent that there is a high prevalence of microcalcifications in both carotid and peripheral lower limb lesions. Additionally, an inverse relationship exists between calcified particle volume and maximum-recorded attenuation density. CONCLUSION: The density-weighted Agatston calcium scoring methodology needs to be reviewed. Calcium scoring which differentiates between critical calcification morphologies, rather than presenting a density-weighted score, is required to direct high-risk plaques towards tailored treatment.


Subject(s)
Carotid Artery Diseases/diagnostic imaging , Lower Extremity/blood supply , Peripheral Arterial Disease/diagnostic imaging , Plaque, Atherosclerotic , Vascular Calcification/diagnostic imaging , X-Ray Microtomography , Aged , Carotid Artery Diseases/surgery , Female , Humans , Male , Middle Aged , Peripheral Arterial Disease/surgery , Predictive Value of Tests , Prognosis , Radiographic Image Interpretation, Computer-Assisted , Reproducibility of Results , Rupture, Spontaneous , Severity of Illness Index , Vascular Calcification/surgery
14.
Cancer Chemother Pharmacol ; 82(5): 865-876, 2018 11.
Article in English | MEDLINE | ID: mdl-30178115

ABSTRACT

PURPOSE: 5-Fluorouracil (5FU) drug exposure correlates with treatment response and toxicity in cancer patients. Dosing is based upon body surface area which does not correlate with 5FU pharmacokinetics (PK)/pharmacodynamics. Therapeutic drug monitoring has enabled real-time 5FU dose adjustments: reducing toxicity with increased efficacy. The aim of this study was to assess feasibility of a 5FU monitoring service utilising a commercial kit in a quaternary cancer centre and to compare PK parameters to previously published studies. METHODS: Cancer patients receiving continuous infusional (CI) 5FU with ECOG PS 0-2, and adequate organ function, were eligible. Patients had blood samples taken at t = 0, mid infusion (if feasible) then 2 h pre infusion end. 5FU levels were measured using a commercial kit (My-5FU PCM™). A feasibility questionnaire was completed by trial nurses and toxicity data were recorded at baseline and at the commencement of the next cycle. 5FU pharmacokinetic exposure parameters were calculated. RESULTS: Twenty patients (12 male; 8 female), median age 62, (range 37-71) had samples taken. Twenty (100%) feasibility forms were available for assessment. Blood samples were taken at 51/69 (74%) specified time points. Ease of sample processing was recorded as easy in all 20 patients. Patient compliance with scheduled visits was 18/20 (90%). One form noted other difficulties with predicting end of infusion time. 19/20 patients had blood samples analysed. Mean measured 5FU AUC (0-Tlast) for 5FU 1 g/m2 with platinum: 35.8 h mg/L (range 28.56-44.26), mean Css 372.2 µg/L (range 297.5-461.0); 5FU 600 mg/m2 with platinum: 12.42 h mg/L (range 6.91-18.29), mean Css 111.0 µg/L (72.0-190.5) and 5FU 2400 mg/m2 as part of FOLFOX ± bevacizumab: 14.75 h mg/L (range 6.74-22.93), mean Css 320.70 µg/L (range 146.5-498.5). One patient had grade 4 neutropenia and one patient without PK parameters experienced febrile neutropenia (grade 4 neutropenia). Mucositis was observed in two patients: [5FU/platinum (1), grade 1, FOXFOX ± bevacizumab (1) grade 1]. Diarrhoea was reported in three patients [5FU/platinum (2) grade 1-2, FOXFOX ± bevacizumab (1) grade 1]. CONCLUSION: Therapeutic 5FU drug monitoring was feasible using commercial kits and analysers and hence warrants development as a routine standard of care in cancer patients. The variability in the 5FU exposure parameters is consistent with other studies using the My 5FU PCM kit.


Subject(s)
Ambulatory Care/methods , Drug Monitoring/methods , Fluorouracil/blood , Oncology Service, Hospital , Aged , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Area Under Curve , Blood Specimen Collection , Drug Monitoring/instrumentation , Drug-Related Side Effects and Adverse Reactions/blood , Drug-Related Side Effects and Adverse Reactions/etiology , Drug-Related Side Effects and Adverse Reactions/prevention & control , Feasibility Studies , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Fluorouracil/therapeutic use , Humans , Infusions, Intravenous , Male , Neoplasms/blood , Neoplasms/drug therapy , Patient Compliance , Pilot Projects , Specimen Handling
15.
Acta Biomater ; 80: 228-236, 2018 10 15.
Article in English | MEDLINE | ID: mdl-30218776

ABSTRACT

Calcification morphology can determine atherosclerotic plaque stability and is associated with increased failures rates for endovascular interventions. Computational efforts have sought to elucidate the relationship between calcification and plaque rupture in addition to predicting tissue response during aggressive revascularisation techniques. However, calcified material properties are currently estimated and may not reflect real tissue conditions. The objective of this study is to correlate calcification mechanical properties with three radiographic density groups obtained from corresponding Computed Tomography (CT) images. Seventeen human plaques extracted from carotid (n = 10) and peripheral lower limb (n = 7) arteries were examined using micro-computed tomography (µCT), simultaneously locating the calcified deposits within their internal structure and quantifying their densities. Three radiographic density groups were defined based on the sample density distribution: (A) 130-299.99 Hounsfield Units (HU), (B) 300-449.99 HU and (C) >450 HU. Nanoindentation was employed to determine the Elastic Modulus (E) and Hardness (H) values within the three density groups. Results reveal a clear distinction between mechanical properties with respect to radiographic density groups (p < 0.0005). No significant differences exist in the density-specific behaviours observed between carotid and peripheral samples. Previously defined calcification classifications indicate an association with specific radiographic density patterns. Scanning Electron Microscopy (SEM) examination revealed that density group A regions consist of both calcified and non-calcified tissues. Further research is required to define the radiographic thresholds which identify varying degrees of tissue calcification. This study demonstrates that the mechanical properties of fully mineralised atherosclerotic calcification emulate that of bone tissues (17-25 GPa), affording computational models with accurate material parameters. STATEMENT OF SIGNIFICANCE: Global mechanical characterisation techniques disregard the heterogeneous nature of atherosclerotic lesions. Previous nanoindentation results for carotid calcifications have displayed a wide range. This study evaluates calcification properties with respect to radiographic density obtained from Micro-CT images. This is the first work to characterise calcifications from peripheral lower limb arteries using nanoindentation. Results demonstrate a strong positive correlation between radiographic density and calcification mechanical properties. Characterising calcifications using their density values provides clarity on the variation in published properties for calcified tissues. Furthermore, this study confirms the hypothesis that fully calcified plaque tissue behaviour similar to that of bone. Appropriate material parameters for calcified tissues can now be employed in computational simulations.


Subject(s)
Atherosclerosis/diagnostic imaging , Atherosclerosis/physiopathology , Calcinosis/diagnostic imaging , Calcinosis/physiopathology , Aged , Arteries/pathology , Arteries/ultrastructure , Biomechanical Phenomena , Elastic Modulus , Female , Hardness , Humans , Male , X-Ray Microtomography
16.
J Vasc Surg ; 67(4): 1234-1246.e2, 2018 04.
Article in English | MEDLINE | ID: mdl-28899569

ABSTRACT

OBJECTIVE: Parameters other than maximum diameter that predict rupture of abdominal aortic aneurysms (AAAs) may be helpful for risk-benefit analysis in individual patients. The aim of this study was to characterize the biomechanical-structural characteristics associated with AAA walls to better identify the related mechanistic variables required for an accurate prediction of rupture risk. METHODS: Anterior AAA wall (n = 40) and intraluminal thrombus (ILT; n = 114) samples were acquired from 18 patients undergoing open surgical repair. Biomechanical characterization was performed using controlled circumferential stretching tests combined with a speckle-strain tracking technique to quantify the spatial heterogeneity in deformation and localized strains in the AAA walls containing calcification. After mechanical testing, the accompanying microstructural characteristics of the AAA wall and ILT types were examined using electron microscopy. RESULTS: No significant correlation was found between the AAA diameter and the wall mechanical properties in terms of Cauchy stress (rs = -0.139; P = .596) or stiffness (rs = -0.451; P = .069). Quantification of significant localized peak strains, which were concentrated in the tissue regions surrounding calcification, reveals that peak strains increased by a mean of 174% as a result of calcification and corresponding peak stresses by 18.2%. Four ILT types characteristic of diverse stages in the evolving tissue microstructure were directly associated with distinct mechanical stiffness properties of the ILT and underlying AAA wall. ILT types were independent of geometric factors, including ILT volume and AAA diameter measures (ILT stiffness and AAA diameter [rs = -0.511; P = .074]; ILT stiffness and ILT volume [rs = -0.245; P = .467]). CONCLUSIONS: AAA wall stiffness properties are controlled by the load-bearing capacity of the noncalcified tissue portion, and low stiffness properties represent a highly degraded vulnerable wall. The presence of calcification that is contiguous with the inner wall causes severe tissue overstretching in surrounding tissue areas. The results highlight the use of additional biomechanical measures, detailing the biomechanical-structural characteristics of AAA tissue, that may be a helpful adjunct to improve the accuracy of rupture prediction.


Subject(s)
Aorta, Abdominal/physiopathology , Aortic Aneurysm, Abdominal/complications , Aortic Rupture/etiology , Thrombosis/complications , Vascular Calcification/complications , Aged , Aorta, Abdominal/diagnostic imaging , Aorta, Abdominal/surgery , Aorta, Abdominal/ultrastructure , Aortic Aneurysm, Abdominal/diagnostic imaging , Aortic Aneurysm, Abdominal/physiopathology , Aortic Aneurysm, Abdominal/surgery , Aortic Rupture/diagnostic imaging , Aortic Rupture/physiopathology , Aortography/methods , Biomechanical Phenomena , Computed Tomography Angiography , Female , Humans , Male , Microscopy, Electron, Scanning , Middle Aged , Multidetector Computed Tomography , Regional Blood Flow , Risk Assessment , Risk Factors , Spectroscopy, Fourier Transform Infrared , Thrombosis/diagnostic imaging , Thrombosis/physiopathology , Thrombosis/surgery , Vascular Calcification/diagnostic imaging , Vascular Calcification/physiopathology , Vascular Calcification/surgery
17.
Ann Vasc Surg ; 44: 421.e1-421.e4, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28479458

ABSTRACT

BACKGROUND: Ulnar artery aneurysms are rare with less than 150 previously reported. Previously ulnar aneurysms have been most commonly noted as occurring in the distal ulnar artery close to the palmar arch. METHODS: We present the case of a 47-year-old male with a background history of human immunodeficiency virus (HIV) who attended our outpatient clinic with symptoms of distal embolization from a proximal ulnar artery aneurysm. RESULTS: Preoperatively, the aneurysm was thought to arise from the distal brachial artery, and only intraoperatively was the diagnosis of ulnar aneurysm made. The aneurysm was excised, and a reverse vein bypass graft anastomosed end to side on the brachial artery, and end to end on the distal ulnar. True ulnar artery aneurysms also involving the more proximal ulnar artery have been previously reported associated with vasculitic disorders. HIV has been previously associated with aneurysm formation in a number of anatomical locations. This case is noteworthy as it reports on the presentation and successful operative management of a true ulnar artery aneurysm arising in the proximal forearm in the setting of HIV, which has not been previously reported in medical literature. CONCLUSIONS: We present successful operative management of a true ulnar aneurysm in the proximal forearm using a reverse venous interposition bypass. Diagnosis of a proximal ulnar artery aneurysm may represent a diagnostic challenge given its rarity as it may mimic brachial artery aneurysm.


Subject(s)
Aneurysm/complications , Brachial Artery/surgery , Forearm/blood supply , HIV Infections/complications , Ulnar Artery , Vascular Grafting/methods , Veins/transplantation , Aneurysm/diagnostic imaging , Aneurysm/surgery , Brachial Artery/diagnostic imaging , HIV Infections/diagnosis , Humans , Male , Middle Aged , Treatment Outcome , Ulnar Artery/diagnostic imaging , Ulnar Artery/surgery , Ultrasonography, Doppler, Color
18.
Vascular ; 23(1): 93-8, 2015 Feb.
Article in English | MEDLINE | ID: mdl-24717960

ABSTRACT

The last two decades have seen increasing adoption of minimally invasive approaches to lumbar disc herniation management. As with many new advances in surgery, the risk profile of these contemporary approaches has yet to be well defined. We present the case of a 32-year-old man who presented with decreasing exercise tolerance over a 6-month period after microendoscopic lumbar discectomy and lamino-foraminotomy. Subsequent work-up revealed a large fistula between his right common iliac artery and inferior vena cava, resulting in high-output cardiac failure. This was managed well with an endovascular approach. This case highlights the importance of complication cognizance for patients who undergo minimally invasive lumbar disc surgery, as serious consequences can occur.


Subject(s)
Arteriovenous Fistula/therapy , Diskectomy/adverse effects , Endoscopy/adverse effects , Endovascular Procedures , Foraminotomy/adverse effects , Iliac Artery/injuries , Intervertebral Disc Displacement/surgery , Laminectomy/adverse effects , Microsurgery/adverse effects , Vascular System Injuries/therapy , Vena Cava, Inferior/injuries , Adult , Arteriovenous Fistula/diagnosis , Arteriovenous Fistula/etiology , Arteriovenous Fistula/physiopathology , Cardiac Output, High/etiology , Diskectomy/methods , Endoscopy/methods , Endovascular Procedures/instrumentation , Heart Failure/etiology , Humans , Iliac Artery/diagnostic imaging , Iliac Artery/physiopathology , Male , Microsurgery/methods , Stents , Tomography, X-Ray Computed , Treatment Outcome , Ultrasonography, Doppler, Color , Vascular System Injuries/diagnosis , Vascular System Injuries/etiology , Vascular System Injuries/physiopathology , Vena Cava, Inferior/diagnostic imaging , Vena Cava, Inferior/physiopathology
19.
Clin Immunol ; 147(1): 50-57, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23518598

ABSTRACT

In allergen challenged animal models, eosinophils localize to airway nerves leading to vagally-mediated hyperreactivity. We hypothesized that in allergic rhinitis eosinophils recruited to nasal nerves resulted in neural hyperreactivity. Patients with persistent allergic rhinitis (n=12), seasonal allergic rhinitis (n=7) and controls (n=10) were studied. Inferior nasal turbinate biopsies were obtained before, 8 and 48h after allergen challenge. Eight hours after allergen challenge eosinophils localized to nerves in both rhinitis groups; this was sustained through 48h. Bradykinin challenge, with secretion collection on the contralateral side, was performed to demonstrate nasal nerve reflexes. Twenty fourhours after allergen challenge, bradykinin induced a significant increase in secretions, indicating nasal hyperreactivity. Histological studies showed that nasal nerves expressed both vascular cell adhesion molecule-1 (VCAM-1) and chemokine (C-C motif) ligand 26 (CCL-26). Hence, after allergen challenge eosinophils are recruited and retained at nerves and so may be a mechanism for neural hyperreactivity.


Subject(s)
Allergens/immunology , Eosinophils/immunology , Nasal Mucosa/immunology , Nervous System/immunology , Rhinitis, Allergic, Perennial/immunology , Rhinitis, Allergic, Seasonal/immunology , Chemokine CCL26 , Chemokines, CC/immunology , Chemokines, CC/metabolism , Eosinophils/metabolism , Humans , Immunohistochemistry , Nasal Mucosa/innervation , Nasal Mucosa/metabolism , Nasal Provocation Tests , Nervous System/metabolism , Rhinitis, Allergic , Rhinitis, Allergic, Perennial/metabolism , Rhinitis, Allergic, Seasonal/metabolism , Vascular Cell Adhesion Molecule-1/immunology , Vascular Cell Adhesion Molecule-1/metabolism
20.
Am J Surg ; 200(4): e51-2, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20887834

ABSTRACT

Acute aortic plaque rupture is an uncommon cause of acute lower limb ischemia. The authors report sequence computed tomographic imaging of a distal aortic plaque rupture in a young man with bilateral lower limb complications. Clinical awareness, prompt recognition and imaging, and appropriate treatment of this uncommon condition are necessary to improve patient outcomes.


Subject(s)
Aneurysm, Ruptured/complications , Aortic Aneurysm, Abdominal/complications , Embolism/complications , Intermittent Claudication/etiology , Popliteal Artery , Acute Disease , Adult , Aneurysm, Ruptured/diagnostic imaging , Aneurysm, Ruptured/surgery , Angiography , Aortic Aneurysm, Abdominal/diagnostic imaging , Aortic Aneurysm, Abdominal/surgery , Aortography , Diagnosis, Differential , Embolectomy/methods , Embolism/diagnostic imaging , Embolism/therapy , Humans , Intermittent Claudication/diagnostic imaging , Intermittent Claudication/therapy , Male , Thrombolytic Therapy/methods , Tomography, X-Ray Computed
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