A preliminary clinical study on endoscopic measurement of lesion area with the method of digital image processing technology / 生物医学工程学杂志

It is of great importance to measure the lesion area in scientific research and clinical practice. The present study aims to solve barrel distortion and measure lesion area with the technology of computer visualization. With the ultimate purpose to obtain the precise lesion area, the study, based on the original endoscopy system and digital image processing technology, dealt with the correction of barrel distortion by lens adjustment, calculated the gastric ulcer area with the aid of Qt database and finally developed an image processing software--Endoscope Assistant (EAS). The results showed that the EAS was accurate in vitro. It was employed to measure the gastric ulcer area of 45 patients and the results were compared with the traditional formula method. It could be well concluded that this technology is safe, accurate and economical for measuring gastric ulcer area.

A new computerized endoscopic balloon manometry to detect esophageal variceal pressure: experimental validation and clinical feasibility / 中华消化内镜杂志

Objective To evaluate the clinical reliability and feasibility of computerized endoscopic balloon manometry in vitro and in vivo, in measurement of pressure of esophageal varices. Methods Computerized endoscopic balloon manometry was used to measure the pressure of variceal model with different diameter (3 mm, 6 mm and 8 mm) and intraluminal pressures (ranging from 8 to 36 mm Hg), and the findings were compared with actual pressures. The technique was also applied in 23 patients with liver cirrhosis and esophageal varices, and its correlation with hepatic venous pressure gradient and other factors related with varices bleeding. Results The study in vitro showed that the measured intraluminal pressure was correlated significantly with the actual value ( r ≥ 0. 993, P ＜ 0. 001 ) without obvious measurement bias(95% CI = -0.13 cm H2O to 0. 33 cm H2O). The measurement in 23 patients were success with little variation coefficient (r≥0. 998) between repeated procedures. Regression analysis showed a good correlation between variceal pressure and hepatic venous pressure gradient (r=0. 858, P ＜ 0. 001 ). A higher variceal pressure was strongly associated with presence of previous bleeding episodes, vascular diameter and presence of red color signs, but did not correlate with the parameter of Child-Pugh classification ( t = 0. 31, P =0. 76). Conclusion Computerized endoscopic balloon manometry is reliable and feasible to examine esophageal variceal pressure, and is very likely to be a valuable clinical index for variceal bleeding.

A study of manometry of esophageal varices based on computer vision / 生物医学工程学杂志

Non-invasive manometry of esophageal varices is a cynosure of researchers. This paper develops a method based on computer vision. Experiments results reveal that correct pressure value can be got quickly.

Study of a digital video system for manometry of esophageal varices / 中华消化杂志

Objective To develop a digital video system for esophageal variceal manometry and to evaluate its reliability. Methods The system consists of esophageal variceal manometer, pressure transducer, video capture card and special computer programs. An artificial esophagus containing water-filled latex tube was designed, in which the pressure had been measured by this system in vitro. The pressures of esophageal varices had been measured by using the method in five patients. Results In vitro study, a good correlation was showed between the actual pressure and measured pressure in the artificial varices with different diameter (3,6,9 mm)(r=0.975, P