Evaluation of disinfection and sterilization of reusable angioscopes with the duck hepatitis B model.
(1/11)
PURPOSE: Nosocomial transmission of viral hepatitis and retrovirus infection has been reported. The expected risk is greatest for the hepatitis B virus (HBV). The duck HBV (DHBV) has similar biologic and structural characteristics to HBV and has been adopted as a suitable model for disinfectant testing. METHODS: Angioscopic examination of the external jugular vein was performed on DHBV-infected ducks. After use, the instrument was air dried for 3 minutes. Samples were obtained by flushing the channel with 5 mL of phosphate buffered saline solution. The samples were collected immediately after drying (control), after flushing with 5 mL of water, after glutaraldehyde disinfection for 5, 10, and 20 minutes, and after ethylene oxide gas sterilization. Angioscopes were either precleaned or uncleaned before disinfection/sterilization. Residual infectivity was assessed with inoculation of samples into the peritoneal cavity of day-old ducks (n = 231). RESULTS: DNA analysis results of liver samples showed that all 38 control ducks became infected. The frequency of DHBV infection was reduced to 93% (14 of 15) by flushing the angioscope with 5 mL of sterile water. No transmission occurred after the use of any of the properly precleaned and disinfected/sterilized angioscopes. However, after the use of the uncleaned angioscopes, the transmission rate was 90% (9 of 10) and 70% (7 of 10) after 5 and 10 minutes of contact time, respectively, in 2% glutaraldehyde. Even after the recommended 20 minutes of contact time, there was still 6% (2 of 35) transmission. After ethylene oxide sterilization, two of the recipient ducklings (2 of 35) were infected with DHBV. CONCLUSION: There was no disease transmission after reuse of disposable angioscopes adequately cleaned before disinfection or sterilization. However, if the angioscopes are inadequately cleaned, DHBV can survive despite glutaraldehyde disinfection or ethylene oxide sterilization. This contrasts with previous in vitro and in vivo data with solid surgical instruments. It is postulated that the presence of a narrow lumen or residual protein shielding within the lumen may compromise effective inactivation of hepadnaviruses on angioscopes, with the potential risk for patient-to-patient transmission. (+info)
Carbon dioxide column angioscopy: a new endovascular imaging technique.
(2/11)
A new angioscopic technique with a CO(2) gas medium for prolonged viewing sessions in the carotid artery is described. A stationary column of CO(2) gas, angled 17-30 degrees subhorizontally and buoyed against a balloon catheter, can be safely maintained. During 10-20-min sessions in dogs, endothelia, thrombi, stent filaments, coils, and an intimal flap were visualized. This technique eliminates the need for continuous saline infusion, which has prevented the application of angioscopy in the carotid artery. (+info)
Prospective randomized study comparing the Teleflex Medical SaphLITE Retractor to the Ethicon CardioVations Clearglide Endoscopic System.
(3/11)
BACKGROUND: Several minimally invasive saphenous vein harvesting techniques have been developed to reduce morbidities associated with coronary artery bypass grafting. This prospective, randomized study was designed to compare two commonly used minimally invasive saphenous vein harvesting techniques, the SaphLITE Retractor System (Teleflex Medical) and the Clearglide Endoscopic Vessel Harvesting System (Ethicon CardioVations, Inc.). METHODS: Between January 2003 and March 2004, a total of 200 patients scheduled for primary, nonemergent coronary artery bypass grafting, with or without concomitant procedures were randomized into two groups: SaphLITE (n = 100) and Clearglide (n = 100). Pre-, intra- and postoperative data was collected and subjected to statistical analysis. Randomization provided homogenous groups with respect to preoperative risk factors. RESULTS: Harvest location for the SaphLITE group was thigh (n = 40), lower leg (n = 5) and both lower leg and thigh (n = 55). The location of harvest for the Clearglide group was thigh (n = 3), lower leg (n = 16) and both lower leg and thigh (n = 81). The mean incision length was 3.6 cm (range, 2-6) in the SaphLITE group versus 2.1 cm (range, 1-4) in the Clearglide group (p < 0.05). The total incision length was 12.9 cm versus 8.9 (p < 0.05) in the SaphLITE and Clearglide groups. Conversion to the open technique occurred in 5 SaphLITE patients and 7 Clearglide patients. Intraoperative leg exploration for bleeding occurred in two of the Clearglide patients and none of the SaphLITE patients. Post-operative complications specifically related to minimally invasive harvesting technique, including a two-week post-discharge visit, were not statistically different between the groups. CONCLUSION: The saphenous vein can be safely harvested utilizing the SaphLITE and Clearglide systems. While the Clearglide system allows for fewer incisions (number and length) and less harvest time, these benefits may be outweighed by the increased cost of the Clearglide system compared to the SaphLITE retractor. (+info)
MRI endoscopy using intrinsically localized probes.
(4/11)
Magnetic resonance imaging (MRI) is traditionally performed with fixed externally applied gradient magnetic fields and is hence intrinsically locked to the laboratory frame of reference (FoR). Here a method for high-resolution MRI that employs active, catheter-based, tiny internal probes that utilize the spatial properties of the probe itself for localization is proposed and demonstrated at 3 T. Because these properties are intrinsic to the probe, they move with it, transforming MRI from the laboratory FoR to the FoR of the device itself, analogous to an endoscope. The "MRI endoscope" can utilize loop coils and loopless antennas with modified sensitivity, in combination with adiabatic excitation by the device itself, to restrict the MRI sensitivity to a disk-shaped plane a few mm thick. Excitation with the MRI endoscope limits the eddy currents induced in the sample to an excited volume whose size is orders of magnitude below that excited by a conventional body MRI coil. Heat testing shows maximum local temperature increases of <1 degrees C during MRI, within regulatory guidelines. The method is demonstrated in a kiwifruit, in intact porcine and rabbit aortas, and in an atherosclerotic human iliac artery specimen, with in-plane resolution as small as 80 microm and 1.5-5 mm slice thickness. (+info)
Imaging of lysophosphatidylcholine in human coronary plaques by color fluorescence angioscopy.
(5/11)
Lysophosphatidylcholine (LPC) is a proinflammatory and proatherogenic substance, and it plays an important role in the initiation, progression, and destabilization of atherosclerotic plaques. If LPC in the vascular wall is visualized in vivo, the mechanisms of atherosclerosis and the effects of medical and interventional therapies on atherosclerosis can be objectively evaluated. Therefore, this study was carried out to visualize LPC in human coronary plaques using a color fluorescence angioscopy (CFA) system. (1) The fluorescence characteristics of LPC were investigated by color fluorescence microscopy (CFM) using Trypan blue dye (TB) as an indicator. For fluorescence imaging, a combination of a band-pass filter (345 nm) and a band-absorption filter of 420 nm (A imaging), or a combination of a band-pass filter (470 nm) and a band-absorption filter of 520 nm (B imaging) was employed. (2) The fluorescence of LPC in the excised human coronary plaques was investigated by CFA and CFM scanning using the same filters as those in CFM. In the presence of TB, LPC exhibited a red fluorescence in both A and B imaging. This red fluorescence color in both A and B imaging was not observed for the other known major substances that constitute the atherosclerotic plaques. This red fluorescence color in both A and B imaging was detected by CFA in both white and yellow plaques that were classified by conventional angioscopy. This fluorescence color was found to be distributed in a web-like or diffuse configuration by CFM scanning. LPC in the human coronary plaques was successfully visualized by CFA using TB as an indicator. (+info)
Towards real-time intravascular endoscopic magnetic resonance imaging.
(6/11)
Coronary angioscopy will not replace angiography as the gold standard for imaging atherosclerotic coronary arteries. However, there may well be a clinical niche for a technology that gives accurate information regarding a specific lesion, if that information can be used to improve the acute or chronic outcome of an interventional procedure. Our experience demonstrates that angioscopy indeed provides this information. Using angioscopy, we now have access to information regarding arterial wall disease that heretofore has been available only at necropsy. In addition, whereas angiography has provided only a 2-dimensional, gray-scale image of the coronary vessels, angioscopy offers a full-color, 3-dimensional perspective of the intracoronary surface morphology. These important lesion-specific details, not reliably available from angiography alone, may ultimately be used to improve patient outcome and to assess risk. (+info)