Use of Intraosseous Doppler Ultrasonography to Study Skeletal Physiology - Echo-Os Study: Exploratory Study Before Its Use in Space Physiology
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 30
- 试验地点
- 3
- 主要终点
- Change in tibial intracortical blood flow velocity, induced by physiological maneuvers in supine position (sub-protocol 1)
研究概览
简要总结
Use of intraosseous Doppler ultrasonography to study skeletal physiology ("Echo-Os Study"). Exploratory study before its use in space physiology.
Bones have a complex vascular network providing nutrients and oxygen to bone cells. The physiology of intraosseous blood circulation remains very little known to date, particularly in human. Human bone vascularization studying is very difficult because of a lack of simple tools for functional exploration of bone vascular perfusion. For blood flow studies, ultrasonography is best suited, allowing for dynamic non-invasive measures. Bone has until now been considered to stop ultrasound and therefore prevent any intraosseous measurements. From a physics viewpoint, bones conduct ultrasound waves well, but they are reflected differently compared to soft tissues. A specific analysis of the ultrasound returned by the bone, using specific correction factors, is therefore needed to interpret ultrasound signals, reconstruct an anatomical image, and extract physiological information. The system proposed in this study combines standard conventional low-frequency ultrasound probes with a specific analysis of ultrasound wave reflection. This system makes it possible to reconstruct an anatomical bone image and record the pulsatile signal of intraosseous vascular perfusion. The investigators will use this system to study the vascular reactivity induced by different physiological maneuvers.
This protocol proposes to study the following mechanisms of blood flow regulation at the level of tibia cortical bone: flow-mediated dilation induced by endothelium (with arterial occlusion test), vasoconstriction induced by sympathetic activation (with static handgrip test), and vasoconstriction induced by veno-arteriolar reflex (with venous occlusion test). This is a pilot study in physiology performed with healthy volunteers. This study will verify whether our intraosseous ultrasound system can properly measure physiological responses expected during these maneuvers. This protocol will also establish links between perfusion and bone architecture at tibial level.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 20 Years 至 70 Years（Adult, Older Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •for sub-protocol 1:
- •Male aged 20-40 years
- •Inclusion criteria for sub-protocol 2:
- •Male aged 20-40 years & 50-70 years
- •Body height of at least 180 cm (in order to have tibia length of 43-45 cm allowing the positioning of ultrasonic probe at distal tibia, and occlusive cuff at calf level)
- •Bone densitometry with available report performed within 5 last years (if none has been done, possibility to perform densitometry covered by the study at selection or inclusion visit)
- •Inclusion criteria common for both sub-protocols:
- •Healthy volunteer without chronic pathology (in particular no known rhythm disorder) or long-term treatment
- •No symptomatic acute medical event requiring treatment on the visit days
- •No history of tibia fractures
- •Body Mass Index between 19 and 26
- •Affiliation to the French Social Security System
- •Written informed consent
- •Non-Inclusion criteria:
- •Inability to stay still for 20 minutes (tremor)
- •Active smoking (stopped less than 1 year ago)
- •History of prolonged corticosteroid treatment
- •Deprivation of liberty by legal or administrative decision
- •Subject to involuntary psychiatric treatment
- •Subject to a legal protection measure
- •For sub-study 1: Osteoporosis known at interview
排除标准
- •Any abnormality or deviation from the selection criteria identified during the clinical examination at the inclusion visit (non-sinus rhythm in ECG, body temperature > 38°C, blood pressure or heart rate outside the defined standards, etc.)
研究组 & 干预措施
"Intraosseous ultrasonography"
All subjects of each sub-protocol receive identical intervention (single group assignment for each of 2 sub-protocols).
干预措施: Intraosseous ultrasonography at tibia before, during, and after a physiological vascular stimulation (venous occlusions, arterial occlusion, handgrip) (Device)
结局指标
主要结局
Change in tibial intracortical blood flow velocity, induced by physiological maneuvers in supine position (sub-protocol 1)
时间窗: before, at the end of venous occlusion (40 mmHg 3 minutes); before, at the end of arterial occlusion (200 mmHg 2 min); at 2, 5, and 10 min of post-occlusion period; before, at the end of handgrip (30% maximum voluntary force for 3 minutes)
Velocity (mm/s) of intracortical blood flow at medial tibia level and its response to venous occlusion, arterial occlusion, handgrip, will be assessed via Ultrasound Vector Flow Mapping
次要结局
- Change in leg skin and muscle blood flow, induced by physiological maneuvers in supine position (sub-protocol 1)(before, at the end of venous occlusion (40 mmHg 3 minutes); before, at the end of arterial occlusion (200 mmHg 2 min); at 2, 5, and 10 min of post-occlusion period; before, at the end of handgrip (30% maximum voluntary force for 3 minutes))
- Comparison of changes in tibial intracortical blood flow with changes in leg skin and muscle blood flow, induced by physiological maneuvers in supine position (sub-protocol 1)(before, at the end of venous occlusion (40 mmHg 3 minutes); before, at the end of arterial occlusion (200 mmHg 2 min); at 2, 5, and 10 min of post-occlusion period; before, at the end of handgrip (30% maximum voluntary force for 3 minutes))
- Reproducibility of the change in tibial intracortical blood flow velocity, induced by physiological maneuvers in supine position (sub-protocol 1)(before, at the end of venous occlusion (40 mmHg 3 minutes); before, at the end of arterial occlusion (200 mmHg 2 min); at 2, 5, and 10 min of post-occlusion period; before, at the end of handgrip (30% maximum voluntary force for 3 minutes))
- Change in tibial intracortical blood flow velocity, induced by occlusion maneuvers in +45° head up tilt position (sub-protocol 2)(Ultrasonography acquisition sequences of 5 secondes will be performed before and during each occlusions.)
- Change in tibial ultradistal bone blood flow velocity, induced by occlusion maneuvers in +45° head up tilt position (sub-protocol 2)(Ultrasonography acquisition sequences of 5 secondes will be performed before and during each occlusions.)
- Comparison of intraosseous ultrasonography and computed tomography for Cortical bone thickness characterisation (sub-protocol 2)(First, intraosseous ultrasonography is performed at +45° head up tilt position (30 minutes for all occlusion steps), then the subject sits down and tomography is performed (10 minutes))
- Comparison of intraosseous ultrasonography and computed tomography for Cortical bone porosity characterisation (sub-protocol 2)(First, intraosseous ultrasonography is performed at +45° head up tilt position (30 minutes for all occlusion steps), then the subject sits down and tomography is performed (10 minutes))