Accuracy of the dose delivery in prostate cancer patients-using an electronic portal imaging device [EPID]

Background: To correct patient positioning errors [setup errors] during prostate cancer treatment using EPID and fiducial gold markers, to improve the accuracy of the dose delivery in these patients

Materials and Methods: Fifteen patients with localized prostate carcinoma after implantation of fiducial gold markers in their prostate gland underwent the five-field IMRT planning technique. The plan was prepared in accordance with ICRU 50 guidance [PTV to receive 95-107% dose]. The software program reconstructed the three-dimensional position of the markers from the different Beams Eye Views [BEV]. The discrepancies of the seeds' positions [prostate surrogate] between plan and daily images were calculated three dimensionally. Then, necessary corrections were applied to match the prostate fiducial markers in the portal image with the BEV image in the planned one by moving the couch in the X, Y and Z directions

Results: Data from 15 patients and 469 fractions of radiotherapy were analyzed in this study. Two sets of data were available from EPID software before and after 3D set-up corrections. The mean of the population displacement in Left /Right [L/R], Anterior/Posterior [A/P] and Crania/Caudal [C/C] directions were 0.5, -1.0 and 2.4mm before, and -0.1, -0.5 and 0.9mm after corrections, respectively. The systematic and random errors for the measured populations in the three mentioned directions were 2.4, 2.7 and 2mm and 6.4, 5.9 and 6.1mm before corrections, and 1.1, 2.4 and 1.4mm and 3.8, 3.9 and 3.6mm after corrections, correspondingly

Conclusion: This study provides further evidence that using gold markers in the prostate improves dose delivery to the prostate. Also, it has been demonstrated that the EPID can be a powerful tool in the reduction of treatment setup errors and the quality assurance and verification of complex treatments

[Comparison of bleeding and transfusion in patients who undergo coronary artery bypass grafting with and without cardiopulmonary bypass]

Excessive Bleeding continues to play a key role and an important cause of morbidity and mortality after cardiopulmonary bypass [CPB]. The goal of this study was to determine the differences in bleeding and transfusion between OPCAB and on -pump CABG patients. In a randomized, double blinded prospective study 300 patient's undergoing coronary revascularization surgery were enrolled, 150 CABG patients were compared with 150 OPCAB patients. The patients were assessed during the first 72 hours to determine the postoperative side effects. The 2 groups were compared using the chi-square test or fisher's exact test and the rank sum test. CABG patients received more intraoperative red blood cells [P<0.0001], more albumin and more fresh- frozen plasma [P<0.0001]. Postoperatively, CABG patients were more likely to receive more platelets [29.3% ? 70.7%, P<0.007]. During the operative and the initial 4-hour postoperative period OPCAB patients exhibited greater blood loss [P<0.0001]; however, at 12,24and 72 hours postoperatively, CABG patients exhibited greater blood loss. There were4 death in CABG patients [P<0.05]. Despite not reversing the heparin at the end of the OPCAB surgery, OPCAB surgery was associated with an overall reduction in platelets, fresh- frozen plasma, Albumin and transfusion requirements