Contrast Enhanced Multispectral Optoacoustic Tomography and MRI for Non-invasive Assessment of Intestinal Transit Time in Children With Chronic Bowel Emptying Disorders
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- ICG signal intensitiy
研究概览
简要总结
The project presented here is a monocentric clinical study conducted by the Pediatric Surgery and Pediatrics departments of the University Hospital Erlangen. The study aims to experimentally expand the diagnostic approach for patients aged 0-17 years suffering from chronic bowel emptying disorders, regardless of any underlying causal or previously treated conditions.
At the core of this clinical study is the application of Multispectral Optoacoustic Tomography (MSOT) in combination with the oral contrast agent Indocyanine Green (ICG) to measure gastrointestinal transit time in children. Unlike conventional X-ray diagnostics, MSOT is radiation-free and considered non-invasive, although it has not yet been standardized for routine clinical use. Additionally, a contrast-free, non-invasive MRI technique will be employed to assess the peristalsis of intestinal segments.
The study aims to standardize the collection and evaluation of patient data following the administration of ICG and subsequent measurements using MSOT and MRI. The objective is to assess gastrointestinal transit time and peristalsis and, ultimately, to optimize therapy for affected patients. This is of particular importance in the coloproctology specialist consultation within the Pediatric Surgery and Pediatrics departments, as follows:
It enables differentiation between patients with slow transit constipation and outlet obstruction.
It allows for a more targeted application and evaluation of neuromodulation therapy, which is used within clinical studies.
This approach allows for the identification of specific intestinal segments with delayed transit time, enabling targeted electrical stimulation of these regions.
A control group of healthy adult volunteers will participate in the study on a voluntary basis.
详细描述
The term chronic defecation disorders encompasses a wide range of conditions in the current medical literature. Among them, idiopathic chronic constipation represents the central subgroup of patients, often suffering from therapy-refractory symptoms. However, other causes of chronic defecation disorders must also be considered, such as Hirschsprung's disease, cystic fibrosis, congenital malformations and their postoperative complications, or neurogenic bladder and rectal emptying disorders. Additionally, chronic fissures, congenital anal stenosis, and previous abdominal surgeries can contribute to chronic defecation disorders.
In most cases, the underlying cause is not a single, well-controlled symptom but rather a heterogeneous symptom complex. Chronic constipation, for instance, is defined based on various symptoms as per the Rome IV criteria, requiring a duration of at least three months for diagnosis. In children, this condition frequently presents as a combination of defecation difficulties, severe abdominal pain, food refusal, encopresis, enuresis, and reduced activity levels, often necessitating a multimodal and sometimes highly burdensome therapy. Patients typically experience significant distress and markedly reduced quality of life.
The prevalence of chronic constipation in children and adolescents is high, with reported rates reaching up to 34%. However, in more than 90% of cases, no organic cause can be identified. Conservative treatment approaches are often inadequate or fail to prevent long-term chronicity. Despite this, defecation disorders in children and adolescents are frequently underestimated and sometimes managed within psychiatric treatment settings, which may lead to long-term physical and psychological developmental impairments.
Diagnostic Challenges
Following the exclusion of manifest organic causes, the differentiation between "slow transit constipation" (STC) and "outlet obstruction" (OO) remains a major diagnostic challenge in children. Further complicating matters, many pediatric patients exhibit mixed forms of both conditions.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Diagnostic
- 盲法
- None
入排标准
- 年龄范围
- 1 Year 至 —（Child, Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Patient Group
- •Written informed consent from the participant (starting at age 6).
- •Written informed consent from the legal guardian(s).
- •Suspected or confirmed diagnosis of chronic defecation disorder.
- •Age ≤ 18 years.
- •Willingness and ability to participate, with sufficient German language skills to understand the informed consent document.
- •Control Group
- •Written informed consent from the participant.
- •Age > 18 years.
- •BMI < 25 or medical suitability for MSOT examination as assessed by a physician.
- •Willingness and ability to participate, with sufficient German language skills to understand the informed consent document.
排除标准
- •Age < 1 year.
- •Pregnancy or breastfeeding.
- •Tattoos in the examination area.
- •Subcutaneous fat tissue thickness > 3 cm.
- •Known hypersensitivity to ICG, sodium iodide, or iodine.
- •Thyroid dysfunction, including hyperthyroidism or focal/diffuse thyroid autonomy.
- •Recent thyroid function testing with radioactive iodine treatment (within two weeks before or after the study).
- •Impaired renal function.
- •Use of specific medications, including:
- •Beta-blockers,
- •Anticonvulsants,
- •Cyclopropane,
- •Bisulfite compounds,
- •Haloperidol,
- •Meperidine,
- •Metamizole,
- •Methadone,
- •Morphine,
- •Nitrofurantoin,
- •Opium alkaloids,
- •Phenobarbital,
- •Phenylbutazone,
- •Probenecid,
- •Rifamycin,
- •Any injection containing sodium bisulfite.
- •General contraindications for MRI, such as electrical implants (e.g., pacemakers, perfusion pumps).
- •Severe claustrophobia preventing MRI examination.
研究组 & 干预措施
Control Group
The control group consists of young, healthy adults without bowel emptying disorders. The aim of this group is to provide baseline measurements for gastrointestinal transit time and peristalsis using Multispectral Optoacoustic Tomography (MSOT) and MRI, allowing for comparison with the intervention group and ensuring the reliability of the diagnostic approach.
干预措施: MSOT with ICG (Diagnostic Test)
Control Group
The control group consists of young, healthy adults without bowel emptying disorders. The aim of this group is to provide baseline measurements for gastrointestinal transit time and peristalsis using Multispectral Optoacoustic Tomography (MSOT) and MRI, allowing for comparison with the intervention group and ensuring the reliability of the diagnostic approach.
干预措施: MRI (Diagnostic Test)
Transit Disorder Group
The intervention group consists of pediatric patients suffering from chronic defecation disorders, including idiopathic chronic constipation, slow transit constipation (STC), and outlet obstruction (OO). The aim of the intervention is to assess gastrointestinal transit time and peristalsis using a novel, non-invasive combination of Multispectral Optoacoustic Tomography (MSOT) and MRI.
干预措施: MSOT with ICG (Diagnostic Test)
Transit Disorder Group
The intervention group consists of pediatric patients suffering from chronic defecation disorders, including idiopathic chronic constipation, slow transit constipation (STC), and outlet obstruction (OO). The aim of the intervention is to assess gastrointestinal transit time and peristalsis using a novel, non-invasive combination of Multispectral Optoacoustic Tomography (MSOT) and MRI.
干预措施: MRI (Diagnostic Test)
结局指标
主要结局
ICG signal intensitiy
时间窗: From enrollment to the end of measurements after one week
Measurement of qualitative and quantitative ICG signal within the lumen of the GI tract, expressed in arbitrary units (AU).
MRI-Based Diagnostic Image Quality
时间窗: From enrollment to the end of measurements after one week
Assessment of overall MRI image quality using a standardized grading scale.
MRI Motion Robustness
时间窗: Time Frame: From enrollment to the end of measurements after one week.
Evaluation of motion artifacts in MRI imaging, scored on a predefined motion robustness scale.
MRI-Based Peristalsis Frequency
时间窗: Time Frame: From enrollment to the end of measurements after one week
Measurement of peristaltic contractions per minute in different intestinal segments.
MRI-Based Peristalsis Amplitude
时间窗: Time Frame: From enrollment to the end of measurements after one week.
Quantification of bowel wall movement amplitude in millimeters (mm).
次要结局
- Single-Wavelength Optoacoustic Signal(From enrollment to the end of measurements after one week)
- Optoacoustic Spectrum Analysis(From enrollment to the end of measurements after one week)
- Ultrasound imaging(From enrollment to the end of measurements after one week)
- Gastrointestinal Symptom Assessment(From enrollment to the end of the study after one year.)
- Demographic parameters(From enrollment to the end of measurements after one week)
研究者
Dr. med. Sonja Diez
PD Dr. med. Sonja Diez
Friedrich-Alexander-Universität Erlangen-Nürnberg