Role of Hydrocolonic Sonography in the Detection of Colonic Neoplastic Lesions

Abstract

This article evaluates the role of hydrocolonic sonography in the study of colon neoplastic lesions in daily gastroenterology practice. Consecutive patients referred for optical colonoscopy were randomly and prospectively enrolled to hydrocolonic sonography. All patients went through hydrocolonic sonography (HS) before optical colonoscopy (OS). In total, 108 patients (57 men), with an average age of 68.9 years, participated in the study. Indications for colonoscopy were colorectal cancer screening (50.0%), unspecific abdominal symptoms (45.4%), and liver metastasis or suspicious lymph nodes (4.6%). Inspection of the entire colon was possible in 86.8% of patients by OC and 89.6% of patients by HS. Globally, the sensitivity and specificity of HS in polyp detection were 24.2% and 99.7%, respectively. For polyps >10 mm, hydrocolonic sonography achieved sensitivity, specificity, positive predictive value, and negative predictive value of 80.0%, 99.7%, 92.8%, and 99.5%, respectively. Optical colonoscopy detected 12 cancers, all identified with hydrocolonic sonography, showing a sensitivity and specificity of 100%. The technique was well tolerated by 94.3% of patients. Hydrocolonic sonography is feasible, safe, well tolerated, and inexpensive, allowing the detection of polyps larger than 10 mm and colon cancer with good accuracy in this study population. In the appropriate setting, it may be a complementary technique in the study of the colon.

Hydrocolonic Sonography. A Forgotten Technique

“…In our study, HS sensitivity for small lesions was low, but improved in the case of larger lesions (Table 3). This relation, directly proportion-al between sensitivity and size, has been observed in previous studies, in which lesions smaller than 7 mm sensitivity ranged between 0 [3] and 5% [5], while in lesions equal to or greater than 7 mm a sensitivity of 12,5 % has been mentioned [6], although most range between 50 and 91% [2,3,5]. In adenocarcinomas, which are bigger lesions (Table 1 and 2), sensitivity was higher between 70.6 and 100% [2][3][4][5][7][8][9][10][11].…”

“…HS exhibits the typical limitations of ultrasound such as those related with obsesity [3,6], poor acoustic window [3], the presence of gas [3,5] or high operator dependency. Furthermore, the presence of faecal remains [3,5], the existence of anatomical variants such as the redundancy of sigmoid colon [5], the existence of poorly repleted areas or the disposition of the transverse colon make the study difficult. HS requires toleration to repletion and although it is possible to decrease the volume of saline solution that is introduced, incomplete studies may result [3,6].…”

“…Furthermore, the presence of faecal remains [3,5], the existence of anatomical variants such as the redundancy of sigmoid colon [5], the existence of poorly repleted areas or the disposition of the transverse colon make the study difficult. HS requires toleration to repletion and although it is possible to decrease the volume of saline solution that is introduced, incomplete studies may result [3,6]. Complications such as vasovagal episodes and diaphoresis have also been reported [6].…”

“…By contrast, the use of ultrasound in the detection of lesions of the colon is not widespread, since the findings described, such as wall thickening, irregular hypoechoic wall, and / or loss of stratification [2,3], frequently correspond to advanced stages of the disease. Its main limitation is the presence of intracolonic gas, which prevents the correct visualization of the colonic wall.…”

“…Its main limitation is the presence of intracolonic gas, which prevents the correct visualization of the colonic wall. However, this gas can be removed by the retrograde instillation of a water or saline solution in the colon as an enema [2][3][4][5][6][7][8][9][10][11][12]. This technique called Hydrocolonic Sonography (HS), fills and relaxes the colon, significantly improving its visualization.…”