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Copyright of Journal of Medical Imaging & Radiation Sciences is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose To report the commissioning and validation of deformable image registration(DIR) software for adaptive contouring. Methods DIR (SmartAdapt®v13.6) was validated using two methods namely contour propagation accuracy and landmark tracking, using physical phantoms and clinical images of various disease sites. Five in-house made phantoms with various known deformations and a set of 10 virtual phantoms were used. Displacement in lateral, anterio-posterior (AP) and superior-inferior (SI) direction were evaluated for various organs and compared with the ground truth. Four clinical sites namely, brain (n = 5), HN (n = 9), cervix (n = 18) and prostate (n = 23) were used. Organs were manually delineated by a radiation oncologist, compared with the deformable image registration (DIR) generated contours. 3D slicer v4.5.0.1 was used to analyze Dice Similarity Co-efficient (DSC), shift in centre of mass (COM) and Hausdorff distances Hf 95%/avg . Results Mean (SD) DSC, Hf 95% (mm), Hf avg (mm) and COM of all the phantoms 1–5 were 0.84 (0.2) mm, 5.1 (7.4) mm, 1.6 (2.2) mm, and 1.6 (0.2) mm respectively. Phantom-5 had the largest deformation as compared to phantoms 1–4, and hence had suboptimal indices. The virtual phantom resulted in consistent results for all the ROIs investigated. Contours propagated for brain patients were better with a high DSC score (0.91 (0.04)) as compared to other sites (HN: 0.84, prostate: 0.81 and cervix 0.77). A similar trend was seen in other indices too. The accuracy of propagated contours is limited for complex deformations that include large volume and shape change of bladder and rectum respectively. Visual validation of the propagated contours is recommended for clinical implementation. Conclusion The DIR algorithm was commissioned and validated for adaptive contouring. [ABSTRACT FROM AUTHOR]

Objective: This study investigated whether postoperative low cardiac output and mortality in obstructed total anomalous pulmonary venous connection could be reduced by selective vertical vein patency. Methods: Fifty-eight patients undergoing rechanneling of total anomalous pulmonary venous connection between 1997 and 2006 were studied. The vertical vein was left patent in 27 patients (group I) and ligated in 31 (group II). Mean ages were 1.49 ± 1.63 and 4.37 ± 3.38 months for groups I and II, respectively. Results: Operative mortalities were 29.1% and 7.4% for ligated and unligated groups, respectively (relative risk 1.75, 1.16-2.64, P = .036). Age younger than 1 month, obstructive total anomalous pulmonary venous connection, hypoplastic pulmonary veins, pulmonary hypertensive crisis, low cardiac output, and vertical vein ligation were significant risk factors for death according to logistic regression analysis. Patients with obstructed total anomalous pulmonary venous connection undergoing vertical vein ligation demonstrated predominant right ventricular dysfunction (relative risk 2.93, 1.28-6.73, P = .011), pulmonary hypertensive crisis (relative risk 2.90, 1.25-6.75, P = .013), and 3.28 times the risk of death (95% confidence interval 1.08-9.99, P = .032) relative to the unligated group. Conclusions: In a subset of patients with obstructed total anomalous pulmonary venous connection, an unligated vertical vein reduces pulmonary arterial pressure, decreases perioperative pulmonary hypertensive crises, provides a temporary pop-off valve during pulmonary hypertensive crisis, and improves survival by providing superior hemodynamics. The high mortality in the ligated group suggests that patients with obstructed total anomalous pulmonary venous connection with postbypass moderate pulmonary hypertension possibly should not undergo vertical vein ligation. We propose routine use of an adjustable ligature around the vertical vein in all patients with more than moderate post-bypass pulmonary hypertension, allowing gradual tightening in increments without multiple reoperations. [Copyright &y& Elsevier]