Intestinal Hyperechogenicity Confirmed by Evaluation of Gray Spectra

Condition(s) studied

Investigational drug(s) / intervention(s)

Evaluation of echogenicity: Patients ongoing a routine 2nd or 3rd trimester ultrasound will have an extra 5 minutes of ultrasound with a specific intestinal setting

Study summary

Hyperechoic bowel is an ultrasound anomaly observed in screening and diagnostic ultrasound, and associated with various fetal pathologies including cystic fibrosis, chromosomal abnormalities, maternal-fetal infections (notably Cytomegalovirus CMV) and intrauterine growth retardation. Suspicion of hyperechogenic intestines in a fetus during a screening ultrasound leads to referral of the mother to a specialized antenatal diagnostic consultation. If the diagnosis is confirmed, this may lead to further investigations, including genetic analyses, which are costly for the healthcare system. However, many of the patients referred after a screening examination for this reason actually have their diagnosis invalidated during the specialized consultation. These "false alarms" lead to an overload of specialist consultations, and are a source of concern for couples.

. However, many of the patients referred after a screening examination for this reason actually have their diagnosis invalidated during the specialist consultation. These "false alarms" lead to an overload of specialist consultations, and are a source of concern for couples.

The diagnosis of intestinal hyperechogenicity is difficult because it is based on the sonographer's subjective impression, with a 3-grade gradation according to the echogenicity of the intestine in relation to the bone (Slotnick and Abuhamad. 1996). According to this method, the evaluation is carried out by progressively decreasing the gain applied to the image: if the hyperechoic bowel disappears before the iliac bone, it's a grade 1; if the bowel and iliac bone disappear at the same time, it's a grade 2; and finally if the bowel is still visible on the image while the iliac bone has disappeared, it's a grade 3.

In addition to gain, which, if too high, tends to overestimate the diagnosis of hyperechoic bowel, other ultrasound parameters can vary the subjective impression of bowel echogenicity, such as the use of high-frequency probes or the application of harmonics, which also lead to overdiagnosis (Lee and Cho. 2003).

Eligibility

Primary outcome measure(s)

• Grey level comparison — At inclusion
  The gray levels measured on the fetal intestines will be compared before and after the application of a pre-established "intestines" adjustment program to the same patient carrying a healthy fetus during an ultrasound scan performed in the second or third trimester of pregnancy, by producing two gray level histograms covering two groups of pixels contained in 10x10mm ellipses containing either the fetal intestines or part of the fetal bone. The histograms obtained are associated with a greyscale average, provided by the camera. We will calculate the ratio between the average grey levels of the intestines and the bone, before and after applying the settings. The aim is therefore to compare, quantitatively and accurately, the gray levels at intestinal and bone levels in second- and third-trimester fetuses, before and after the application of specific presettings.

Trial sites (1)

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