Carotid stenosis: what is the high-risk population?

Uncovering the Hidden: A Study on Incidental Findings on CBCT Scans Leading to External Referrals

OBJECTIVES

This project aims to determine the prevalence of cone-beam computed tomography (CBCT) findings requiring referral. Additionally, the goal is to establish a reference standard protocol for incidental findings, outlining indications for further investigation and management protocol.

METHODS

Patients records from the Advanced Imaging Centre at the School of Dentistry, University of Alberta, underwent systematic examination to identify CBCT incidental findings. Radiographic findings requiring referral were categorised into 8 anatomic zones. Analysis assessed prevalence and a management protocol was developed for significant findings. Inferential analyses were conducted to determine the frequency and prevalence of specific findings requiring further investigation.

RESULTS

A total of 1260 CBCT interpretive reports were analysed. The most prevalent radiographic findings outside the areas of interest were found in the cervical vertebrae (18%), followed by the sinuses (15%), temporomandibular joints (8%), jaw lesions (7%), airway (5%), teeth (5%), soft tissue calcifications (5%), and other (1%).

CONCLUSIONS

Findings most commonly requiring external referral included carotid atheroma (2.7%), cervical vertebrae osteoarthritis (0.97%), jaw lesions (0.86%), adenoid and/or tonsillar hypertrophy (0.86%), and paranasal sinus pathology (0.73%). Increased medicolegal awareness and practitioner knowledge contribute to the rising number of CBCT-identified radiographic findings outside the area of concern. The study addresses the debate on reporting all CBCT/radiographic findings by exploring their prevalence and providing protocols. These guidelines assist dentists in identification, decision-making, and referral processes.

Transcarotid arterial revascularization is feasible and safe with concomitant inferior vena cava occlusion

Transcarotid artery revascularization (TCAR) has risen as a promising minimally invasive intervention for high-risk patients with favorable anatomy. TCAR's noninferiority to carotid endarterectomy regarding stroke is reliant on its flow reversal technology and lack of aortic arch manipulation. We present the case of a 79-year-old man with a chronically occluded inferior vena cava who safely underwent staged bilateral TCAR for bilateral high-grade carotid artery stenosis. Although chronic inferior vena cava occlusion alters flow mechanics, we suspect that any pressure gradient facilitating retrograde flow from the carotid artery to the femoral vein provides neuroprotective benefits.

Vortical Structures Promote Atheroprotective Wall Shear Stress Distributions in a Carotid Artery Bifurcation Model

Carotid artery diseases, such as atherosclerosis, are a major cause of death in the United States. Wall shear stresses are known to prompt plaque formation, but there is limited understanding of the complex flow structures underlying these stresses and how they differ in a pre-disposed high-risk patient cohort. A 'healthy' and a novel 'pre-disposed' carotid artery bifurcation model was determined based on patient-averaged clinical data, where the 'pre-disposed' model represents a pathological anatomy. Computational fluid dynamic simulations were performed using a physiological flow based on healthy human subjects. A main hairpin vortical structure in the internal carotid artery sinus was observed, which locally increased instantaneous wall shear stress. In the pre-disposed geometry, this vortical structure starts at an earlier instance in the cardiac flow cycle and persists over a much shorter period, where the second half of the cardiac cycle is dominated by perturbed secondary flow structures and vortices. This coincides with weaker favorable axial pressure gradient peaks over the sinus for the 'pre-disposed' geometry. The findings reveal a strong correlation between vortical structures and wall shear stress and imply that an intact internal carotid artery sinus hairpin vortical structure has a physiologically beneficial role by increasing local wall shear stresses. The deterioration of this beneficial vortical structure is expected to play a significant role in atherosclerotic plaque formation.

Shear stress metrics associated with pro-atherogenic high-risk anatomical features in a carotid artery bifurcation model

BACKGROUND

Diseases associated with atherosclerotic plaques in the carotid artery are a major cause of deaths in the United States. Blood-flow-induced shear-stresses are known to trigger plaque formation. Prior literature suggests that the internal carotid artery sinus is prone to atherosclerosis, but there is limited understanding of why only certain patients are predisposed towards plaque formation.

METHODS

We computationally investigate the effect of vessel geometry on wall-shear-stress distribution by comparing flowfields and wall-shear-stress-metrics between a low-risk and a novel predisposed high-risk carotid artery bifurcation anatomy. Both models were developed based on clinical risk estimations and patient-averaged anatomical features. The high-risk geometry has a larger internal carotid artery branching angle and a lower internal-to-carotid-artery-diameter-ratio. A patient-averaged physiological carotid artery inflow waveform is used.

FINDINGS

The high-risk geometry experiences stronger flow separation in the sinus. Furthermore, it experiences a more equal flow split at the bifurcation, thereby reducing internal carotid artery flowrate and increasing atherosclerosis-prone low-velocity areas. Lowest time-averaged-wall-shear-stresses are present at the sinus outer wall, where plaques are often found, for both geometries. The high-risk geometry has significantly high, unfavorable oscillatory-shear-index values not found in the low-risk geometry. High oscillatory-shear-index areas are located at the vessels outside walls distal to the bifurcation and on the sinus wall.

INTERPRETATION

These results highlight the effectiveness of oscillatory-shear-index, to augment classical time-averaged-wall-shear-stress, in evaluating pro-atherogenic geometry features. Furthermore, the flow split at the bifurcation is a promising clinical indicator for atherosclerosis risk as it can be directly accessed using clinical imaging, whereas shear-stress-metrics cannot.

Effect of the FDA Safety and Innovation Act on racial and gender diversity in neurosurgical device trials

OBJECTIVE

The US FDA uses evidence from clinical trials in its determination of safety and utility. However, these trials have often suffered from limited external validity and generalizability due to unrepresentative study populations with respect to clinical patient demographics. Section 907 of the FDA Safety and Innovation Act (FDASIA) of 2012 attempted to address this issue by mandating the reporting of certain study demographics in new device applications. However, no study has been performed on its effectiveness in the participant diversity of neurosurgical device trials.

METHODS

The FDA premarket approval (PMA) online database was queried for all original neurosurgical device submissions from January 1, 2006, to December 31, 2019. Endpoints of the study included racial and gender demographics of reported effectiveness trials, which were summated for each submission. Chi-square tests were performed on both endpoints for before and after years of FDASIA passage and implementation.

RESULTS

A total of 33 device approvals were analyzed, with 14 occurring before SIA implementation and 19 after. Most trials (96.97%) reported gender to the FDA, while 66.67% reported race and 63.64% reported ethnicity. Gender breakdown did not change significantly post-SIA (53.30% female, p = 0.884). Racial breakdown was significantly different from the 2010 US Census for all races (p < 0.001) both pre- and post-SIA. Only Native American race was significantly different in terms of representation post-SIA, increasing from 0% to 0.63% (p = 0.0187). There was no significant change in ethnicity.

CONCLUSIONS

The FDASIA, as currently written, does not appear to have had a significant impact on the racial or gender diversity of neurosurgical device clinical trial populations. This may be due to the noncompulsory nature of its guidance, or a lack of more stringent regulation on the composition of clinical trials themselves.

[Comparative analysis of safety of carotid endarterectomy performed in acutest and acute periods of ischaemic stroke]

Surgical revascularization of the carotid basin in the acutest period of ischaemic stroke, i.e., within 72 hours, will make it possible to prevent the development of recurrent stroke by removing an embologenically dangerous atherosclerotic plaque of the symptomatic carotid artery and to improve cerebral blood supply, having eliminated haemodynamic stenosis of the carotid artery. However, the problem of safety of carotid endarterectomy in patients during the acutest period of ischaemic stroke still remains debatable.

PURPOSE

To comparatively analyse safety of eversion carotid endarterectomy performed in the acutest (0-72 hours) and acute (4-14 days) periods of minor ischaemic stroke.

PATIENTS AND METHODS

Between January 2015 and December 2019, specialists of the Department of Vascular Surgery of Municipal Clinical Hospital # 7 of Kazan performed a total of 80 eversion carotid reconstructions in the period of minor ischaemic stroke within 14 days. The patients were divided into 2 groups depending on the terms of performing carotid endarterectomy. The first group comprised 32 (40.0%) patients operated on in the acutest period of ischaemic stroke, i.e., within 72 hours from the onset of first symptoms of neurological deficit. The second group included 48 (60.0%) patients subjected to carotid endarterectomy within 4 to 14 days from the onset of first signs of neurological deficit.

RESULTS

According to the obtained findings, haemorrhagic transformation in the early postoperative period occured in 2 Group Two patients, with one lethal outcome on POD 3. Cerebral ischaemia increased in one patient of each group without enlargement of the ischaemic zone according to brain computed tomography, with residual neurological deficit in Group I in remote period (Rankin scale score 1) and complete restoration in Group II (Rankin scale score 0). Recurrent minor ischaemic stroke on POD 1 developed in Group II with formation of a new lacunar region of ischaemia of the brain in the operated carotid basin and was verified by the findings of cerebral MRI with persisting neurological deficit for 6 months (Rankin scale score 2). The comparative assessment of severity of stroke on the day of operation and at discharge, as well as that of neurological symptomatology during the 1st and 6th months of follow up in both groups proved positive. No events of acute coronary syndrome, recurrent strokes or lethal outcomes were observed during the follow-up period.

CONCLUSION

According to the findings of our study, patients with acute cerebral circulation impairment caused by embologenically dangerous lesions of internal carotid arteries should be operated on within the first 72 hours, if there are no accompanying changes requiring time for correction thereof.

Repetitive peripheral magnetic stimulation for impairment and disability in people after stroke

BACKGROUND

Repetitive peripheral magnetic stimulation (rPMS) is a non-invasive treatment method that can penetrate to deeper structures with painless stimulation to improve motor function in people with physical impairment due to brain or nerve disorders. rPMS for people after stroke has proved to be a feasible approach to improving activities of daily living and functional ability. However, the effectiveness and safety of this intervention for people after stroke currently remain uncertain. This is an update of the review published in 2017.

OBJECTIVES

To assess the effects of rPMS in improving activities of daily living and functional ability in people after stroke.

SEARCH METHODS

On 7 January 2019, we searched the Cochrane Stroke Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL), in the Cochrane Library; MEDLINE; Embase; the Cumulative Index to Nursing and Allied Health Literature (CINAHL); PsycINFO; the Allied and Complementary Medicine Database (AMED); Occupational Therapy Systematic Evaluation of Evidence (OTseeker); the Physiotherapy Evidence Database (PEDro); ICHUSHI Web; and six ongoing trial registries. We screened reference lists, and we contacted experts in the field. We placed no restrictions on the language or date of publication when searching electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) conducted to assess the therapeutic effect of rPMS for people after stroke. Comparisons eligible for inclusion were (1) active rPMS only compared with 'sham' rPMS (a very weak form of stimulation or a sound only); (2) active rPMS only compared with no intervention; (3) active rPMS plus rehabilitation compared with sham rPMS plus rehabilitation; and (4) active rPMS plus rehabilitation compared with rehabilitation only.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion. The same review authors assessed methods and risk of bias, undertook data extraction, and used the GRADE approach to assess the quality of evidence. We contacted trial authors to request unpublished information if necessary. We resolved all disagreements through discussion.

MAIN RESULTS

We included four trials (three RCTs and one cross-over trial) involving 139 participants. Blinding of participants and physicians was well reported within all trials. We judged the overall risk of bias across trials as low. Only two trials (with 63 and 18 participants, respectively) provided sufficient information to be included in the meta-analysis. We found no clear effect of rPMS on activities of daily living at the end of treatment (mean difference (MD) -3.00, 95% confidence interval (CI) -16.35 to 10.35; P = 0.66; 1 trial; 63 participants; low-quality evidence) and at the end of follow-up (MD -2.00, 95% CI -14.86 to 10.86; P = 0.76; 1 trial; 63 participants; low-quality evidence) when comparing rPMS plus rehabilitation versus sham plus rehabilitation. We found no statistical difference in improvement of upper limb function at the end of treatment (MD 2.00, 95% CI -4.91 to 8.91; P = 0.57; 1 trial; 63 participants; low-quality evidence) and at the end of follow-up (MD 4.00, 95% CI -2.92 to 10.92; P = 0.26; 1 trial; 63 participants; low-quality evidence) when comparing rPMS plus rehabilitation versus sham plus rehabilitation. We observed a significant decrease in spasticity of the elbow at the end of follow-up (MD -0.48, 95% CI -0.93 to -0.03; P = 0.03; 1 trial; 63 participants; low-quality evidence) when comparing rPMS plus rehabilitation versus sham plus rehabilitation. In terms of muscle strength, rPMS treatment was not associated with improved muscle strength of the ankle dorsiflexors at the end of treatment (MD 3.00, 95% CI -2.44 to 8.44; P = 0.28; 1 trial; 18 participants; low-quality evidence) when compared with sham rPMS. No studies provided information on lower limb function or adverse events, including death. Based on the GRADE approach, we judged the quality of evidence related to the primary outcome as low, owing to the small sample size of the studies.

AUTHORS' CONCLUSIONS

Available trials provided insufficient evidence to permit any conclusions about routine use of rPMS for people after stroke. Additional trials with large sample sizes are needed to provide robust evidence for rPMS after stroke.

Surgery for Triple Pathology of Giant Vestibular Schwannoma Associated with Carotid Artery Stenosis and Intracranial Aneurysm: Case Report

Here we report the case of a 56-year-old woman who presented with a highly unusual combination of three pathologies, namely a giant left-sided vestibular schwannoma, severe stenosis of the left internal carotid artery, and a right anterior cerebral artery aneurysm. The chosen approach comprised three consecutive surgical procedures, namely (1) aneurysm embolization, (2) carotid stenosis stenting, and (3) vestibular schwannoma excision. This approach avoided complications and achieved a satisfactory functional outcome. To the best of our knowledge, this combination of three conditions has not been previously reported in the English-language literature.

Dyslipidaemia in the elderly: to treat or not to treat?

INTRODUCTION

The elderly population (i.e. aged ≥ 65 years) is increasing worldwide. Ageing is associated with a higher incidence and prevalence of cardiovascular disease (CVD). Areas covered: The prevalence of CVD risk factors including type 2 diabetes mellitus, hypertension and dyslipidaemia also increases with advancing age, contributing to the higher absolute CVD risk observed in the elderly. The present narrative review comments on the associations of dyslipidaemia with CVD as well as the effects of lifestyle measures and lipid-lowering drugs on lipids and CVD risk with a special focus on the elderly population. Individual treatment goals and therapeutic options according to current guidelines are also reviewed. Finally, we discuss special characteristics of the elderly that may influence the efficacy and safety of drug therapy and should be considered before selection of hypolipidaemic pharmacotherapy. Expert commentary: There may be a greater CVD benefit in older patients following drug therapy compared with younger ones. Treatment goals and therapeutic options should be individualized according to current guidelines. Specific characteristics that may influence the efficacy and safety of drug therapy in the elderly should be considered in relation to dyslipidaemia treatment.

[Carotid artery stenosis treated with modified carotid endarterectomy: report of two cases]

OBJECTIVE

Based on standard carotid endarterectomy, we performed modified carotid endarterectomy in two cases of carotid artery stenosis by changing the direction of the carotid artery incision to avoid restenosis of the internal carotid artery without using a patch. The two patients recovered smoothly without any complications. Compared with eversion or patch endarterectomy, this modified carotid endarterectomy avoids restenosis of the carotid artery and shortens operation time.

Repetitive peripheral magnetic stimulation for activities of daily living and functional ability in people after stroke

BACKGROUND

Repetitive peripheral magnetic stimulation (rPMS) is a form of therapy that creates painless stimulation of deep muscle structures to improve motor function in people with physical impairment from brain or nerve disorders. Use of rPMS for people after stroke has been identified as a feasible approach to improve activities of daily living and functional ability. However, no systematic reviews have assessed the findings of available trials. The effect and safety of this intervention for people after stroke currently remain uncertain.

OBJECTIVES

To assess the effect of rPMS for improving activities of daily living and functional ability in people after stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (August 2016), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 8) in the Cochrane Library (August 2016), MEDLINE Ovid (November 2016), Embase Ovid (August 2016), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) in Ebsco (August 2016), PsycINFO Ovid (August 2016), the Allied and Complementary Medicine Database (AMED) Ovid (August 2016), Occupational Therapy Systematic Evaluation of Evidence (OTseeker) (August 2016), the Physiotherapy Evidence Database (PEDro) (October 2016), and ICHUSHI Web (October 2016). We also searched five ongoing trial registries, screened reference lists, and contacted experts in the field. We placed no restrictions on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) conducted to assess the therapeutic effect of rPMS for people after stroke. Comparisons eligible for inclusion were (1) active rPMS only compared with 'sham' rPMS (a very weak form of stimulation or a sound only); (2) active rPMS only compared with no intervention; (3) active rPMS plus rehabilitation compared with sham rPMS plus rehabilitation; and (4) active rPMS plus rehabilitation compared with rehabilitation only.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion. The same review authors assessed methods and risk of bias and extracted data. We contacted trial authors to ask for unpublished information if necessary. We resolved all disagreements through discussion.

MAIN RESULTS

We included three trials (two RCTs and one cross-over trial) involving 121 participants. Blinding of participants and physicians was well reported in all trials, and overall risk of bias was low. We found no clear effect of rPMS on activities of daily living at the end of treatment (mean difference (MD) -3.00, 95% confidence interval (CI) -16.35 to 10.35; low-quality evidence) and at the end of follow-up (MD -2.00, 95% CI -14.86 to 10.86; low-quality evidence). Investigators in one study with 63 participants observed no statistical difference in improvement of upper limb function at the end of treatment (MD 2.00, 95% CI -4.91 to 8.91) and at the end of follow-up (MD 4.00, 95% CI -2.92 to 10.92). One trial with 18 participants showed that rPMS treatment was not associated with improved muscle strength at the end of treatment (MD 3.00, 95% CI -2.44 to 8.44). Another study reported a significant decrease in spasticity of the elbow at the end of follow-up (MD -0.48, 95% CI -0.93 to -0.03). No studies provided information on lower limb function and death. Based on the GRADE approach, we judged the certainty of evidence related to the primary outcome as low owing to the small sample size of one study.

AUTHORS' CONCLUSIONS

Available trials provided inadequate evidence to permit any conclusions about routine use of rPMS for people after stroke. Additional trials with large sample sizes are needed to determine an appropriate rPMS protocol as well as long-term effects. We identified three ongoing trials and will include these trials in the next review update.

Immediate versus delayed treatment for recently symptomatic carotid artery stenosis

BACKGROUND

The timing of surgery for recently symptomatic carotid artery stenosis remains controversial. Early cerebral revascularization may prevent a disabling or fatal ischemic recurrence, but it may also increase the risk of hemorrhagic transformation, or of dislodging a thrombus. This review examined the randomized controlled evidence that addressed whether the increased risk of recurrent events outweighed the increased benefit of an earlier intervention.

OBJECTIVES

To assess the risks and benefits of performing very early cerebral revascularization (within two days) compared with delayed treatment (after two days) for people with recently symptomatic carotid artery stenosis.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register in January 2016, the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library 2016, Issue 1), MEDLINE (1948 to 26 January 2016), EMBASE (1974 to 26 January 2016), LILACS (1982 to 26 January 2016), and trial registers (from inception to 26 January 2016). We also handsearched conference proceedings and journals, and searched reference lists. There were no language restrictions. We contacted colleagues and pharmaceutical companies to identify further studies and unpublished trials.

SELECTION CRITERIA

All completed, truly randomized trials (RCT) that compared very early cerebral revascularization (within two days) with delayed treatment (after two days) for people with recently symptomatic carotid artery stenosis.

DATA COLLECTION AND ANALYSIS

We independently selected trials for inclusion according to the above criteria, assessed risk of bias for each trial, and performed data extraction. We utilized an intention-to-treat analysis strategy.

MAIN RESULTS

We identified one RCT that involved 40 participants, and addressed the timing of surgery for people with recently symptomatic carotid artery stenosis. It compared very early surgery with surgery performed after 14 days of the last symptomatic event. The overall quality of the evidence was very low, due to the small number of participants from only one trial, and missing outcome data. We found no statistically significant difference between the effects of very early or delayed surgery in reducing the combined risk of stroke and death within 30 days of surgery (risk ratio (RR) 3.32; confidence interval (CI) 0.38 to 29.23; very low-quality evidence), or the combined risk of perioperative death and stroke (RR 0.47; CI 0.14 to 1.58; very low-quality evidence). To date, no results are available to confirm the optimal timing for surgery.

AUTHORS' CONCLUSIONS

There is currently no high-quality evidence available to support either very early or delayed cerebral revascularization after a recent ischemic stroke. Hence, further randomized trials to identify which patients should undergo very urgent revascularization are needed. Future studies should stratify participants by age group, sex, grade of ischemia, and degree of stenosis. Currently, there is one ongoing RCT that is examining the timing of cerebral revascularization.