Feasibility, Accuracy and Reproducibility of Ultrasound in Aneurysms of the Descending Thoracic Aorta
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 60
- 试验地点
- 1
- 主要终点
- Part 1 - Feasibility - Proportion of participants with successful ultrasound measurement of the diameter of the descending thoracic aorta
研究概览
简要总结
The goal of this observational study is to assess the applicability of non-invasive ultrasound in aneurysms of the descending thoracic aorta.
The main question it aims to answer is:
What is the feasibility of Ultrasound to visualise the Descending Thoracic Aorta, and can this imaging modality accurately measure the maximum size of aneurysms and residual sacs with acceptable reproducibility?
Participants are having their diagnosis confirmed or excluded by conventional imaging techniques (CT scans). Participants receive exactly the same standard of care regardless of their participation. The study offers an additional ultrasound scan, and the results will be compared with previous imaging.
详细描述
Aneurysms of the aortic artery are a significant public health issue. The number of newly diagnosed aneurysms of the thoracic aorta is on the rise, and aneurysm rupture is a catastrophic event associated with high mortality rates. The most proximal sections of the aorta (ascending and the aortic arch) are routinely scanned by echocardiography practitioners. The abdominal aorta is also easily visualised on transabdominal ultrasound, and there is a screening programme in the UK that is highly cost-effective and reduced the aneurysm-related number of deaths. However, the portion of the aorta in the chest (descending thoracic aorta) is not routinely assessed by ultrasound practitioners.
The diagnosis of descending thoracic aneurysms relies mostly on imaging techniques that use ionising radiation. In addition, these techniques are expensive and may not be widely available in some regions. In contrast, ultrasound is a non-invasive technique that allows visualisation of most parts of the body. Ultrasound machine suppliers have invested in better systems and transducers over the years and visualisation of the descending thoracic aorta may now be possible.
The main aims of this study are to assess the feasibility (Part 1), accuracy (Part 2) and reproducibility (Part 3) ultrasound in the diagnosis and monitoring of descending thoracic aortic aneurysms. Participants will be recruited from the vascular lab and outpatient clinics, and diameters of the descending thoracic aorta will be measured with non-invasive ultrasound. Data obtained from study measurements will be compared with computed tomography scans that patients had as part of their standard of care.
If the feasibility, accuracy and reproducibility of Ultrasound are clearly demonstrated, routine ultrasound scans of the descending thoracic aorta may be suggested.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Patients with diagnosed AAA or other vascular condition attending the vascular scanning department for routine ultrasound and confirmed healthy DTA (Control group).
- •Patients with known DTAA (including Type B dissection) or patients who had TEVAR previously (Case group).
- •Patients who have had CT as part of their standard of care.
- •Patients able to tolerate the scan (Lying in supine position).
- •Adults aged 18 or over.
- •Willing to provide consent.
排除标准
- •Patient under 18 years of age.
- •Previous thoracic surgery or body deformity (severe kyphosis, scoliosis, pleural effusion or chest wall trauma).
- •Patients without previous imaging of the thoracic aorta.
- •Life expectancy <2 years.
- •Pregnant Women.
- •Patients unwilling to provide consent or unable to comply with study requirements.
- •Patients too frail to travel to routine outpatient appointments.
- •Inability to attend the appointment due to time constraints or other commitments.
- •Although rare, ultrasound contraindications as described in the scanning protocol are also exclusion criteria.
研究组 & 干预措施
CONTROLS
Patients with healthy DTA (30 patients)
CASES
Patients with DTAA or TEVAR (30 patients)
结局指标
主要结局
Part 1 - Feasibility - Proportion of participants with successful ultrasound measurement of the diameter of the descending thoracic aorta
时间窗: Day 1 - At the single ultrasound study visit.
Number and percentage of participants in whom the descending thoracic aortic diameter can be obtained by transthoracic ultrasound. The units of Measure are total number and percentages.
Part 1 - Feasibility - Length of the descending thoracic aorta by Ultrasound
时间窗: Day 1 - At the single ultrasound study visit.
Total length of the descending thoracic aorta from the aortic isthmus to the coeliac axis. The unit of Measure is Centimetres (cms).
Part 1 - Feasibility - Ultrasound Quality Score
时间窗: Day 1 - At the single ultrasound study visit.
Number of ultrasound windows that allow visualisation of the descending thoracic aorta (0 to 3 windows) and allocation of a quality score. The Unit of Measure is a score created for this study (0-Windows: No views; 1 window: Poor; 2 windows: Moderate; 3 windows: Good). Higher scores mean better image quality.
Part 2 - Accuracy - Comparision between Transthoracic Ultrasound and CT
时间窗: Day 1 - At the single ultrasound study visit.
Calculate mean differences and limits of agreement between TUS and CT. Achieve high sensitivity and specificity.
Part 3 - Reproducibility - Intraclass correlation coefficient
时间窗: Day 1 - At the single ultrasound study visit.
Calculate inter- and intra-operator variability by intraclass correlation coefficient (ICC). The study aims to achieve good or excellent reliability.
次要结局
- Part 1 - Feasibility - Factors limiting visualisation of the Descending Thoracic Aorta(Day 1 - At the single ultrasound study visit.)
- Part 1 - Feasibility - Duration of Ultrasound Examination(Day 1 - At the single ultrasound study visit.)
- Part 1 - Feasibility - Patient Feedback Questionnaire(Day 1 - At the single ultrasound study visit.)