[Abstract] Objective To study the selection of acquisition speed and its diagnostic value of dynamic fecography in the examination of functional outlet obstruction constipation. Methods Dynamic fecography was performed on patients with constipation using a digital gastrointestinal machine, and the acquisition speeds of 1 frame/S, 3 frames/S, and 4 frames/S were selected for 68, 76, and 73 cases, respectively, and then measured for the three types of diseases: anterior rectal protrusion, descending perineum, and puborectalis muscle spasm syndrome, respectively. The measured values of the three acquisition speed examinations were statistically analyzed to seek the optimal acquisition speed for dynamic fecal imaging and to evaluate its diagnostic value. RESULTS Dynamic fecography with 1-frame/S acquisition speed was significantly different from 3-frame/S and 4-frame/S in the measurement and display of the three types of diseases, and the latter two acquisition speeds were better. In contrast, there was no statistically significant difference between the 3-frame/S and 4-frame/S acquisition speeds in the measurement and visualization of the three categories of disease. Conclusion Dynamic fecography with 3 and 4 frames/S acquisition speeds can show the three types of functional outlet obstruction constipation well and accurately, but the dynamic fecography with 3 frames/S acquisition speed is the best examination method when analyzing the factors of the radiation dose received by the patient and the loss of the X-ray machine bulb tube. Lei Zhidan, Department of Radiology, Henan Provincial People’s Hospital [Keywords] functional outlet obstruction; constipation; defecography; dynamic acquisition method; diagnostic value The velocity selection of dynamic defecography and it’s diagnostic value in constipation of functional outlet obstruction LEI Zhi-dan , JIA Wu Cling, WEN Ze-jun, LI Jian-min, REN Jin-xiang (Department of Radiology , Henan Provincial People@s Hospital, Zhengzhou, China) Provincial People@s Hospital, Zhengzhou 450003 , China ) [Abstract] Objective To study the velocity selection of dynamic defecography in constipation Objective To study the velocity selection of dynamic defecography in constipation of functional outlet obstruction, and evaluate it’s diagnostic value. Methods The 217 cases’ patients with constipation of The 217 cases’ patients with constipation of functional outlet obstruction were underwent by using digital fluoroscopic imaging unit. The velocity selection of dynamic defecography were The velocity selection of dynamic defecography were separate 1 frame per second,3 and 4 frames per second. The imaging materials including all kinds of velocity and three kinds of diseases were analyzed by a blind study , and the data were processed. The imaging materials including all kinds of velocity and three kinds of diseases were analyzed by a blind study , and the data were processed by statistics. Results Significant differences in constipation of functional outlet obstruction were observed between 1 frame per second and 3 frames per second. Significant differences in constipation of functional outlet obstruction were observed between 1 frame per second and 3 or 4 frames per second. The dynamic defecography with 3 or 4 frames per second velocity was superior to 1 frame per second. The dynamic defecography with 3 or 4 frames per second velocity was superior to 1 frame per second. There were no differences between 3 frames per second and 4 frames per second. The dynamic defecography with 3 or 4 frames per second velocity can both present three kinds of diseases. But thinking of the X-ray dose which patient accepted and the wastage of X-ray unit, the dynamic defecography with 3 frames per second velocity was superior to 1 frame per second. But thinking of the X-ray dose which patient accepted and the wastage of X-ray unit, the dynamic defecography with 3 frames per second velocity is a satisfactory method in diagnosing constipation of functional outlet obstruction. obstruction of functional outlet; constipation; defecography; dynamic photography; diagnostic evaluate Defecography is one of the most important examinations for functional outlet obstruction [1. 2], and scholars at home and abroad have made a lot of efforts in the areas of examination methods, contrast instruments and drugs. Scholars at home and abroad have carried out extensive research on its examination methods, contrast instruments and drugs. However, fewer studies have been conducted on dynamic fecography [2. 3], especially on the selection of acquisition speed for dynamic fecography, which has not been reported by the authors. We collected 217 cases of dynamic fecography with different acquisition speeds from January 2005 to March 2006 and analyzed them to seek the optimal acquisition speed of dynamic fecography and its diagnostic value for functional outlet obstruction constipation. 1 MATERIALS AND METHODS 1.1 General information In this group, there were 217 cases, including 68 cases with an acquisition speed of 1 frame/S, 76 cases with 3 frames/S and 73 cases with 4 frames/S. There were 31 male cases and 186 female cases, and their ages ranged from 23 to 71 years old, with an average age of 38 years old. The shortest history was 3 months, the longest was 33 years, and the average age was 8 months.186 female patients 133 cases had a history of having one child, 41 cases had a history of having 2 or more children, and 12 cases had no history of childbearing.217 cases had different degrees of abdominal distension and discomfort, anal cramping, feeling of incomplete evacuation, and difficulty in defecation, but colonoscopy and barium enema did not show any organic lesions. 1.2 Examination methods The DIAGNOST 93 digital gastrointestinal machine of Philips Company was used for fecal imaging, and the stationary phase, anal lifting phase, forceful evacuation phase and mucous membrane phase were taken respectively. During the process from the beginning to the end of forceful evacuation, 1 frame/S, 3 frames/S, and 4 frames/S were chosen for 68, 76, and 73 patients to take dynamic films, while the resting phase, the anal lifting phase, and the mucosal phase were still taken in the conventional way. The contrast agent was made from barium jelly with simulation effect, which was prepared with reference to the method of Shang Kezhong, Li Dongbing, Wang Zhijie et al [1.4. 5]. 1.3 Methods of analysis A set of data was measured independently and accurately by three radiologists for each of the three categories of rectal proptosis (proptosis depth), perineal descent (anal sitting distance) and puborectal muscle spasm syndrome (arcuate indentation depth) in each group. The measured values were statistically processed separately using SPSS 10.0 for windows software, and the three acquisition speeds of dynamic fecography were compared, so as to seek the optimal acquisition speed of dynamic fecography and evaluate its diagnostic value for functional outlet obstruction diseases. The diagnosis was made according to the criteria of Lu Renhua [1. 6]. 2 RESULTS 2.1 Rectal anterior protrusion Of the 217 patients, 164 had different degrees of rectal anterior protrusion, of which 51 were detected at 1 fps, 57 at 3 fps, and 56 at 4 fps. The maximal depth of anterior protrusion measured at 1 fps was similar to that measured at 3 fps (u1=3.32>2.58, P12.58, P1′2.58, P12.58, P1′2.58, P12.58, P22.58, P12.58, P12.58, P1′2.58, P1′2.58, P22.58, P12.58). 2.58, P22.58, P2′2.58, P22.58, P2′2.58, P32.58, P3′2.58, P32.58, P3′