- Email: [email protected]
Using IVUS to improve treatment of complex lesions in the femoropopliteal arteries
Abstracts Olomouc, Olomouc, Czechia, Czech Republic, 3 Department of Neurosurgery, Ceske Budejovice Hospital, Ceske Budejovice, Czechia, Czech Republic, 4 Department of Neurosurgery, University Hospital Plzen, Plzen, Czechia, Czech Republic, 5 Department of Neurology, Ceske Budejovice Hospital, Ceske Budejovice, Czechia, Czech Republic, 6 Department of Neurology, Comprehensive Stroke Center, Charles University Faculty of Medicine and University Hospital Hradec Kralove, Hradec Kralove, Czechia, Czech Republic Background: Cerebral blood flow volume (BFV) is important factor for accurate diagnosis of neurovascular diseases and treatment indication. Study aims to assess correlations of BFV measurements in cervical and intracranial arteries between quantitative magnetic resonance angiography (qMRA) and duplex sonography. Methods: Consecutive patients with suspicion of cerebral vascular pathology were included in prospective study. All patients underwent qMRA and duplex sonography of the cervical and intracranial arteries with measurement of BFV in bilateral common (CCA), internal (ICA) and externa carotid arteries, vertebral arteries (VAs), middle, anterior and posterior cerebral arteries, posterior communicanting arteries and basilar artery (BA). DS was performed using two ultrasound machines by experienced sonographers. Two patients were examined twice. Correlations between BFV measurements were evaluated using Spearman’s correlation coefficient and inter-class correlation coefficient (ICC). Results: Totally 21 subjects (15 males, mean age 56.3§6.2 years) were included to the study. Duplex sonography inter-investigator correlation was excellent (ICC=0.972) as well as intra-investigator correlations of both qMRA and duplex sonography (ICC˃0.990). Mostly high correlations were recorded between qMRA and duplex sonography BFV measurements in particular cervical arteries but only low to moderate correlations were obtained for intracranial arteries. Mean differences between BFV measurements in CCA and its branches were 10.9§8.1%/15.0§11.9% when using qMRA/ duplex sonography, in ICA siphon and its branches 13.5§11.8%/ 35.4§34.2% when using qMRA/duplex sonography, and in both VAs and BA 24.1§19.7%/44.9§44.0% when using qMRA/duplex sonography, resp. Conclusion: Duplex sonography and qMRA are highly reproducible methods for blood flow volume measurement in cervical and intracranial arteries in routine clinical practice. The study was registered at ClinicalTrials.gov. NCT03591523 and supported by the Ministry of Health of the Czech Republic grants No. 16-29148A, 16-30965A, 17-31016A.
Transcranial doppler cerebral embolus detection during carotid and cardiac surgery: Successes and challenges David H. Evans Department of Cardiovascular Sciences, University of Leicester, United Kingdom Transcranial Doppler ultrasound (TCD) has proven to be a very sensitive tool for detecting emboli in the cerebral circulation. The basic principle of detection is extremely simple: if an embolus backscatters more power than the blood in which it is moving, then the transitory increase in power can be detected and measured. In general even relatively small gas bubbles will be detected, but some larger solid emboli may be missed. TCD has been used to study spontaneous embolism in patients with various conditions including carotid artery stenosis, cardiac disorders, and acute stroke and in many types of interventional procedures including carotid endarterectomy and stenting, catheter ablation for atrial fibrillation, coronary artery bypass grafting and valve replacement surgery. The outcomes of these
S27
studies have been of mixed success: embolus detection during carotid surgery seemingly leading to improvements in surgical and medical treatment, whilst the value of embolus detection during cardiac surgery is still very much in question. In the case of carotid artery surgery intraoperative monitoring has alerted surgeons to manoeuvres during the dissection phase of the operation that are causing embolization to occur and thus change their technique, and has aided in the development of pharmaceutical strategies to dramatically reduce the incidence of stroke in the immediate post-operative period. In the case of cardiac surgery the picture is much less clear. A common problem after cardiac surgery is postoperative cognitive decline (POCD) which has been been attributed to a number of factors including the presence of new ischaemic lesions in the brain due to emboli entering the cerebral circulation during surgery, but there is no clear evidence of this and in a recently published systematic review of 18 studies, 9 studies with a total of 647 patients showed a positive association between POCD and embolic load, whilst in the other 9 with a total of 434 patients there appeared to be no association. There are several reasons why, even if embolization is an important factor, studies have so far failed to prove an association. Firstly although vast numbers of emboli occur during cardiac surgery it is likely that most of them are gaseous and our studies have suggested probably insignificant. Secondly emboli may only be a part of the story as some studies have shown associations between POCD and type of anaesthesia, blood pressure variations, impaired autoregulation, biomarkers associated with inflammation, use of neuroprotective agents, and the use of hypothermia. Using IVUS to improve treatment of complex lesions in the femoropopliteal arteries Richard Allan Senior Vascular Sonographer, Flinders Medical Centre, Bedford Park, SA, Australia Despite rapid advances in in peripheral endovascular therapy over the last 15 years, the rate of restenosis and revascularization in the femoropopliteal arteries remains high. This is particularly the case for more complex lesions, such as longer lesions, those with severe calcification and chronic total occlusions (CTO). The recognised limitations of angiography, particularly the planar and luminal nature of the imaging, result in incomplete assessment of lesion characteristics which may well contribute to problems with achieving satisfactory outcomes. Intravascular ultrasound (IVUS) is a fundamentally different mode of imaging to angiography and is able to produce high quality imaging of the entire artery rather than just the lumen. IVUS provides a range of imaging parameters, many of which are unique to this form of imaging and are unobtainable with angiography. IVUS can therefore assist with a more complete characterisation of the artery and lesion beyond the luminal silhouette and diameters provided by angiography. In this presentation, the role of intravascular imaging (IVUS) in treating complex femoropopliteal lesions will be reviewed, drawing on more than five years’ experience with this technology. The value of IVUS both before and after treatment will be discussed. This will include how pre-treatment IVUS imaging can assist selection of the most appropriate treatment methods by providing accurate assessment of vessel dimensions, length of the diseased segment, severity of calcification, presence of negative remodelling and the degree of plaque eccentricity. This information can inform the choice of treatment technology as well as optimising device size and the length of treatment. IVUS can also provide unique information after initial treatment. This includes accurate measurement of minimum lumen size post angioplasty and stenting, the presence of dissection and the effects of
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atherectomy, including assessment of the effectiveness of plaque removal and identification of vessel wall damage. IVUS imaging is simple, quick and safe to use during endovascular interventions and can provide unique information that can supplement standard angiographic imaging and help optimise treatments. Using ultrasound to assist the treatment of femoropopliteal CTO Richard Allan Senior Vascular Sonographer, Flinders Medical Centre, Bedford Park, SA, Australia Chronic total occlusions (CTO) represent some of the most difficult lesions to treat with endovascular techniques. Crossing the occlusion is a critical step because successful crossing of the lesion must be achieved before treatment can be initiated. Sub-intimal crossing has been a mainstay of endovascular techniques but limits the treatment options available to the interventionist. Luminal crossing is more challenging but provides an opportunity to use adjunctive techniques such as atherectomy that may improve the effectiveness of angioplasty. Conventional imaging methods, such as duplex ultrasound and CTA, have significant limitations for assessing these lesions prior to treatment. In particular the interventionist has no information regarding the presence of vascular micro-channels within these lesions that may provide a path through the occluded lumen and so allow successful luminal crossing. Imaging of micro-channels within CTO has been demonstrated in animals but there are currently no non-invasive means of identifying these structures in humans. In an observational study, we have performed contrast-enhanced ultrasound (CEUS) on 37 patients with femoropopliteal CTO and identified micro-channels in 34 cases (92%). Most micro-channels had a linear configuration and this was associated with a higher rate of complete or partial luminal crossing compared with mixed or tortuous configurations. Identification of micro-channels with CTOs may be useful for planning of the optimal crossing method. We have also investigated the use of conventional ultrasound to directly guide a specialized crossing device through CTOs. Guidance of attempted luminal crossing is currently performed using angiography however this imaging is unable to image the occluded section, limiting ability to guide the crossing wire or device through the lesion. Crossing of CTO using a specialized crossing device was attempted in 56 cases, with ultrasound guidance used in 31 cases and angiographic guidance in 25 cases. There was a significantly higher rate of partial or complete luminal crossing when ultrasound guidance was used. This resulted in a higher rate of atherectomy and a lower rate of secondary stenting compared to angiographic guidance. This experience suggests that ultrasound may have a role in the treatment of CTO both by providing information about the nature of the CTO prior to treatment and by improving the rate of luminal crossing.
SESSION 6D: BREAST Ethnicity and characteristics of triple negative breast cancer (TNBC) Sudhir Vinayak Chair, Radiology Department, AGA Khan University Hospital, Nairobi, Kenya, Africia Studies of the prevalence of hormone receptor status; ER/PR/ HER2 in breast cancer from Sub Saharan Africa (SSA) are fraught with inconsistencies. There are multitude of reasons for these inconsistencies but the most prominent are inadequate breast biopsy material, small sample sizes, poor histopathology services and suboptimal handling of specimens. As an example, ER/PR/HER2 receptors for breast cancers are not part of the routine assessment for breast cancer
Volume 45, Number S1, 2019 and testing is only available in a couple of centers across the entire country. Variability in Radiology, Surgery and laboratory methodology and interpretation makes comparison between data difficult. Available data shows a huge variability in the prevalence of TNBC within the sub-Saharan region. This is due to these factors and almost all suggest a much higher incidence of TNBC compared to the West. Core biopsy as a diagnostic tool is only available in academic or subspecialty hospital settings. Most diagnoses are based on tissue obtained by Fine Needle Aspiration (FNA). Given these constraints, making comparison between breast cancer data from the developed and developing world should be interpreted with caution. As part of a larger funded study investigating the prevalence of Triple Negative Breast Cancer (TNBC) in Kenya, we organized a multidisciplinary workshop for participants from ten provincial health care facilities, all of whom are involved in providing breast cancer care. We sought to provide an overview of TNBC and importance of appropriate tissue collection and handling, identifying gaps in diagnostic processes, suggested remedial strategies and provided hands on training. We describe our experience, impact and outcome of this workshop. Our aim was to accurately determine the histologic type and prevalence of ER/PR/HER2 using standardized methodology of ultrasound guided core biopsies. During the workshop, we trained Physicians how to perform core biopsies, thereafter store and transport biopsy samples. Results: A total of 301 cases of breast cancer were included in the study. Invasive ductal carcinoma (NOS) was the most common histologic type (84.2%). ER positivity was seen in 72.8%, PR in 64.8% and HER2 in 17.6% of all cases. Triple negative breast cancers (TNBC) constituted 20.2 % of the cases. There was a significant association between receptor status and histologic grade (p<0.001) and statistically significant trend of increasing pathological stage of tumor (pT) associated with TNBC (p=0.020). Conclusions: We present a definitive prospective analysis of IHC data from a single center and demonstrate that prevalence of ER/PR/ HER2 receptor status from SSA is comparable with that in the West, which contradicts previous reports. Breast imaging in difficult women Merran McKessar Mater Imaging, Sydney, NSW, Australia Breast imaging can be hard to get right. You can take a beautiful set of images at 2,4,6,8,10 and 12 o’clock in both breasts, documenting normal tissue, and miss the cancer completely. You can simply “miss” the cancer in your survey, or perhaps misinterpret scanned tissue. Breast imaging is operator dependent, and you are the operator. Your ability to provide accurate assessment depends on knowing what you are looking for, your ability to interpret normal from abnormal, and documenting that information accurately. Performing breast ultrasound requires knowledge of anatomy, an understanding of the wide range of normal appearance, and the spectrum of benign, atypical, suspicious and malignant findings superimposed upon this wide range of normal. What can make breast ultrasound difficult includes patient factors such as age, mobility, breast size and density, and history prior surgery or treatment. Lack of information regarding these factors, and even patient demeanour, may also cause difficulty. The reason for breast examination is paramount: Is this a diagnostic examination or a screening study? Is there a history of prior benign, atypical or malignant pathology? Is there an MRI or mammography finding requiring correlation? Is there a clinical lump or symptom that is causing concern? Is the referring doctor’s clinical concern the thing that is worrying this woman?
Transcranial doppler cerebral embolus detection during carotid and cardiac surgery: Successes and challenges David H. Evans Department of Cardiovascular Sciences, University of Leicester, United Kingdom Transcranial Doppler ultrasound (TCD) has proven to be a very sensitive tool for detecting emboli in the cerebral circulation. The basic principle of detection is extremely simple: if an embolus backscatters more power than the blood in which it is moving, then the transitory increase in power can be detected and measured. In general even relatively small gas bubbles will be detected, but some larger solid emboli may be missed. TCD has been used to study spontaneous embolism in patients with various conditions including carotid artery stenosis, cardiac disorders, and acute stroke and in many types of interventional procedures including carotid endarterectomy and stenting, catheter ablation for atrial fibrillation, coronary artery bypass grafting and valve replacement surgery. The outcomes of these
S27
studies have been of mixed success: embolus detection during carotid surgery seemingly leading to improvements in surgical and medical treatment, whilst the value of embolus detection during cardiac surgery is still very much in question. In the case of carotid artery surgery intraoperative monitoring has alerted surgeons to manoeuvres during the dissection phase of the operation that are causing embolization to occur and thus change their technique, and has aided in the development of pharmaceutical strategies to dramatically reduce the incidence of stroke in the immediate post-operative period. In the case of cardiac surgery the picture is much less clear. A common problem after cardiac surgery is postoperative cognitive decline (POCD) which has been been attributed to a number of factors including the presence of new ischaemic lesions in the brain due to emboli entering the cerebral circulation during surgery, but there is no clear evidence of this and in a recently published systematic review of 18 studies, 9 studies with a total of 647 patients showed a positive association between POCD and embolic load, whilst in the other 9 with a total of 434 patients there appeared to be no association. There are several reasons why, even if embolization is an important factor, studies have so far failed to prove an association. Firstly although vast numbers of emboli occur during cardiac surgery it is likely that most of them are gaseous and our studies have suggested probably insignificant. Secondly emboli may only be a part of the story as some studies have shown associations between POCD and type of anaesthesia, blood pressure variations, impaired autoregulation, biomarkers associated with inflammation, use of neuroprotective agents, and the use of hypothermia. Using IVUS to improve treatment of complex lesions in the femoropopliteal arteries Richard Allan Senior Vascular Sonographer, Flinders Medical Centre, Bedford Park, SA, Australia Despite rapid advances in in peripheral endovascular therapy over the last 15 years, the rate of restenosis and revascularization in the femoropopliteal arteries remains high. This is particularly the case for more complex lesions, such as longer lesions, those with severe calcification and chronic total occlusions (CTO). The recognised limitations of angiography, particularly the planar and luminal nature of the imaging, result in incomplete assessment of lesion characteristics which may well contribute to problems with achieving satisfactory outcomes. Intravascular ultrasound (IVUS) is a fundamentally different mode of imaging to angiography and is able to produce high quality imaging of the entire artery rather than just the lumen. IVUS provides a range of imaging parameters, many of which are unique to this form of imaging and are unobtainable with angiography. IVUS can therefore assist with a more complete characterisation of the artery and lesion beyond the luminal silhouette and diameters provided by angiography. In this presentation, the role of intravascular imaging (IVUS) in treating complex femoropopliteal lesions will be reviewed, drawing on more than five years’ experience with this technology. The value of IVUS both before and after treatment will be discussed. This will include how pre-treatment IVUS imaging can assist selection of the most appropriate treatment methods by providing accurate assessment of vessel dimensions, length of the diseased segment, severity of calcification, presence of negative remodelling and the degree of plaque eccentricity. This information can inform the choice of treatment technology as well as optimising device size and the length of treatment. IVUS can also provide unique information after initial treatment. This includes accurate measurement of minimum lumen size post angioplasty and stenting, the presence of dissection and the effects of
S28
Ultrasound in Medicine & Biology
atherectomy, including assessment of the effectiveness of plaque removal and identification of vessel wall damage. IVUS imaging is simple, quick and safe to use during endovascular interventions and can provide unique information that can supplement standard angiographic imaging and help optimise treatments. Using ultrasound to assist the treatment of femoropopliteal CTO Richard Allan Senior Vascular Sonographer, Flinders Medical Centre, Bedford Park, SA, Australia Chronic total occlusions (CTO) represent some of the most difficult lesions to treat with endovascular techniques. Crossing the occlusion is a critical step because successful crossing of the lesion must be achieved before treatment can be initiated. Sub-intimal crossing has been a mainstay of endovascular techniques but limits the treatment options available to the interventionist. Luminal crossing is more challenging but provides an opportunity to use adjunctive techniques such as atherectomy that may improve the effectiveness of angioplasty. Conventional imaging methods, such as duplex ultrasound and CTA, have significant limitations for assessing these lesions prior to treatment. In particular the interventionist has no information regarding the presence of vascular micro-channels within these lesions that may provide a path through the occluded lumen and so allow successful luminal crossing. Imaging of micro-channels within CTO has been demonstrated in animals but there are currently no non-invasive means of identifying these structures in humans. In an observational study, we have performed contrast-enhanced ultrasound (CEUS) on 37 patients with femoropopliteal CTO and identified micro-channels in 34 cases (92%). Most micro-channels had a linear configuration and this was associated with a higher rate of complete or partial luminal crossing compared with mixed or tortuous configurations. Identification of micro-channels with CTOs may be useful for planning of the optimal crossing method. We have also investigated the use of conventional ultrasound to directly guide a specialized crossing device through CTOs. Guidance of attempted luminal crossing is currently performed using angiography however this imaging is unable to image the occluded section, limiting ability to guide the crossing wire or device through the lesion. Crossing of CTO using a specialized crossing device was attempted in 56 cases, with ultrasound guidance used in 31 cases and angiographic guidance in 25 cases. There was a significantly higher rate of partial or complete luminal crossing when ultrasound guidance was used. This resulted in a higher rate of atherectomy and a lower rate of secondary stenting compared to angiographic guidance. This experience suggests that ultrasound may have a role in the treatment of CTO both by providing information about the nature of the CTO prior to treatment and by improving the rate of luminal crossing.
SESSION 6D: BREAST Ethnicity and characteristics of triple negative breast cancer (TNBC) Sudhir Vinayak Chair, Radiology Department, AGA Khan University Hospital, Nairobi, Kenya, Africia Studies of the prevalence of hormone receptor status; ER/PR/ HER2 in breast cancer from Sub Saharan Africa (SSA) are fraught with inconsistencies. There are multitude of reasons for these inconsistencies but the most prominent are inadequate breast biopsy material, small sample sizes, poor histopathology services and suboptimal handling of specimens. As an example, ER/PR/HER2 receptors for breast cancers are not part of the routine assessment for breast cancer
Volume 45, Number S1, 2019 and testing is only available in a couple of centers across the entire country. Variability in Radiology, Surgery and laboratory methodology and interpretation makes comparison between data difficult. Available data shows a huge variability in the prevalence of TNBC within the sub-Saharan region. This is due to these factors and almost all suggest a much higher incidence of TNBC compared to the West. Core biopsy as a diagnostic tool is only available in academic or subspecialty hospital settings. Most diagnoses are based on tissue obtained by Fine Needle Aspiration (FNA). Given these constraints, making comparison between breast cancer data from the developed and developing world should be interpreted with caution. As part of a larger funded study investigating the prevalence of Triple Negative Breast Cancer (TNBC) in Kenya, we organized a multidisciplinary workshop for participants from ten provincial health care facilities, all of whom are involved in providing breast cancer care. We sought to provide an overview of TNBC and importance of appropriate tissue collection and handling, identifying gaps in diagnostic processes, suggested remedial strategies and provided hands on training. We describe our experience, impact and outcome of this workshop. Our aim was to accurately determine the histologic type and prevalence of ER/PR/HER2 using standardized methodology of ultrasound guided core biopsies. During the workshop, we trained Physicians how to perform core biopsies, thereafter store and transport biopsy samples. Results: A total of 301 cases of breast cancer were included in the study. Invasive ductal carcinoma (NOS) was the most common histologic type (84.2%). ER positivity was seen in 72.8%, PR in 64.8% and HER2 in 17.6% of all cases. Triple negative breast cancers (TNBC) constituted 20.2 % of the cases. There was a significant association between receptor status and histologic grade (p<0.001) and statistically significant trend of increasing pathological stage of tumor (pT) associated with TNBC (p=0.020). Conclusions: We present a definitive prospective analysis of IHC data from a single center and demonstrate that prevalence of ER/PR/ HER2 receptor status from SSA is comparable with that in the West, which contradicts previous reports. Breast imaging in difficult women Merran McKessar Mater Imaging, Sydney, NSW, Australia Breast imaging can be hard to get right. You can take a beautiful set of images at 2,4,6,8,10 and 12 o’clock in both breasts, documenting normal tissue, and miss the cancer completely. You can simply “miss” the cancer in your survey, or perhaps misinterpret scanned tissue. Breast imaging is operator dependent, and you are the operator. Your ability to provide accurate assessment depends on knowing what you are looking for, your ability to interpret normal from abnormal, and documenting that information accurately. Performing breast ultrasound requires knowledge of anatomy, an understanding of the wide range of normal appearance, and the spectrum of benign, atypical, suspicious and malignant findings superimposed upon this wide range of normal. What can make breast ultrasound difficult includes patient factors such as age, mobility, breast size and density, and history prior surgery or treatment. Lack of information regarding these factors, and even patient demeanour, may also cause difficulty. The reason for breast examination is paramount: Is this a diagnostic examination or a screening study? Is there a history of prior benign, atypical or malignant pathology? Is there an MRI or mammography finding requiring correlation? Is there a clinical lump or symptom that is causing concern? Is the referring doctor’s clinical concern the thing that is worrying this woman?