Non-invasive cardiac-pulmonary gating is proposed to improve the imaging resolution. It produces signals based on the cardiac-pulmonary motion of an animal in real-time. The system with the non-invasive gating consist...Non-invasive cardiac-pulmonary gating is proposed to improve the imaging resolution. It produces signals based on the cardiac-pulmonary motion of an animal in real-time. The system with the non-invasive gating consists of a digital signal processor (DSP), an electrocardiography (ECG) detection circuit and a thermoeouple circuit. An enhanced R wave detection algorithm based on zero crossing counts is used to adjust the low sample frequency associated with the respiratory rate of an animal. The thermocouple recognizes the respiration phase by sensing the temperature changes of the nasal airflow of an animal. The proposed gating can accurately generate the gating signal for freely breathing mice (weight of around 0.03 kg), and its respiratory signal is too weak to be detected. Apart from non-invasiveness, compared with other existing gating techniques, it occupies minimal space at lower cost. Actually, it can be used in micro-computed tomography (CT) and other systems needed to detect the cardiac-pulmonary motion. Several tests validate that the proposed cardiac-pulmonary gating can generate the gating signal as required. By using the gating technique, the image resolution is improved.展开更多
AIM: To determine the indicated referrals to a tertiary centre for patients with anorectal symptoms, the effect of the advised treatment and the discomfort of the tests.METHODS: In a retrospective study, patients refe...AIM: To determine the indicated referrals to a tertiary centre for patients with anorectal symptoms, the effect of the advised treatment and the discomfort of the tests.METHODS: In a retrospective study, patients referred for anorectal function evaluation (AFE) between May 2004 and October 2006 were sent a questionnaire, as were the doctors who referred them. AFE consisted of anal manometry, rectal compliance measurement and anal endosonography. An indicated referral was defined as needing AFE to establish a diagnosis with clinical consequence (fecal incontinence without diarrhea, 3rd degree anal sphincter rupture, congenital anorectal disorder, inflammatory bowel disease with anorectal complaints and preoperative in patients for re-anastomosis or enterostoma, anal fissure, fistula or constipation). Anal ultrasound is always indicated in patients with fistula, anal manometry and rectal compliance when impaired continence reserve is suspected. The therapeutic effect was noted as improvement, no improvement but reassurance, and deterioration.RESULTS: From the 216 patients referred, 167 (78%) returned the questionnaire. The referrals were indicated in 65%. Of these, 80% followed the proposed advice. Improvement was achieved in 35% and a reassurance in 57% of the patients, no difference existed between patient groups. On a VAS scale (1 to 10) symptoms improved from 4.0 to 7.2. Most patients reported no or little discomfort with AFE. CONCLUSION: Referral for AFE was indicated in 65%. Beneficial effect was seen in 92%: 35% improved and 57% was reassured. Advice was followed in 80%. Better instruction about indication for AFE referral is warranted.展开更多
基金Supported by the National Basic Research Program of China ("973" Program) (2006CB705700)~~
文摘Non-invasive cardiac-pulmonary gating is proposed to improve the imaging resolution. It produces signals based on the cardiac-pulmonary motion of an animal in real-time. The system with the non-invasive gating consists of a digital signal processor (DSP), an electrocardiography (ECG) detection circuit and a thermoeouple circuit. An enhanced R wave detection algorithm based on zero crossing counts is used to adjust the low sample frequency associated with the respiratory rate of an animal. The thermocouple recognizes the respiration phase by sensing the temperature changes of the nasal airflow of an animal. The proposed gating can accurately generate the gating signal for freely breathing mice (weight of around 0.03 kg), and its respiratory signal is too weak to be detected. Apart from non-invasiveness, compared with other existing gating techniques, it occupies minimal space at lower cost. Actually, it can be used in micro-computed tomography (CT) and other systems needed to detect the cardiac-pulmonary motion. Several tests validate that the proposed cardiac-pulmonary gating can generate the gating signal as required. By using the gating technique, the image resolution is improved.
文摘AIM: To determine the indicated referrals to a tertiary centre for patients with anorectal symptoms, the effect of the advised treatment and the discomfort of the tests.METHODS: In a retrospective study, patients referred for anorectal function evaluation (AFE) between May 2004 and October 2006 were sent a questionnaire, as were the doctors who referred them. AFE consisted of anal manometry, rectal compliance measurement and anal endosonography. An indicated referral was defined as needing AFE to establish a diagnosis with clinical consequence (fecal incontinence without diarrhea, 3rd degree anal sphincter rupture, congenital anorectal disorder, inflammatory bowel disease with anorectal complaints and preoperative in patients for re-anastomosis or enterostoma, anal fissure, fistula or constipation). Anal ultrasound is always indicated in patients with fistula, anal manometry and rectal compliance when impaired continence reserve is suspected. The therapeutic effect was noted as improvement, no improvement but reassurance, and deterioration.RESULTS: From the 216 patients referred, 167 (78%) returned the questionnaire. The referrals were indicated in 65%. Of these, 80% followed the proposed advice. Improvement was achieved in 35% and a reassurance in 57% of the patients, no difference existed between patient groups. On a VAS scale (1 to 10) symptoms improved from 4.0 to 7.2. Most patients reported no or little discomfort with AFE. CONCLUSION: Referral for AFE was indicated in 65%. Beneficial effect was seen in 92%: 35% improved and 57% was reassured. Advice was followed in 80%. Better instruction about indication for AFE referral is warranted.