The increased sensitivity of future radio telescopes will result in requirements for higher dynamic range within the image as well as better resolution and immunity to interference. In this paper we propose a new matrix formulation of the imaging equation in the cases of non co-planar arrays and polarimetric measurements. Then we improve our parametric imaging techniques in terms of resolution and estimation accuracy. This is done by enhancing both the MVDR parametric imaging, introducing alternative dirty images and by introducing better power estimates based on least squares, with positive semi-definite constraints. We also discuss the use of robust Capon beamforming and semi-definite programming for solving the self-calibration problem. Additionally we provide statistical analysis of the bias of the MVDR beamformer for the case of moving array, which serves as a first step in analyzing iterative approaches such as CLEAN and the techniques proposed in this paper. Finally we demonstrate a full deconvolution process based on the parametric imaging techniques and show its improved resolution and sensitivity compared to the CLEAN method.

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Transvaginal natural orifice transluminal endoscopic surgery (vNOTES) was previously described as a feasible approach to perform several procedures including hysterectomy followed by uterosacral ligament suspension [1,2]. Approaching the cul-de-sac with vNOTES while the uterus is intact allowing access to the uterosacral ligaments. This enables attainment of apical support by placing sutures on the ligaments, shortening them, and reinforcing their attachment to the cervix. The objective of this video is to demonstrate a surgical technique for vNOTES uterosacral ligament hysteropexy (ULH). Design: Stepwise demonstration of the technique with narrated video footage. This video report is part of an institutional, investigational review board−approved study. Setting: Academic tertiary referral center. Interventions: This video presents our team's vNOTES technique for ULH in a woman aged 37 years (gravida 3 para 3) who presented with pelvic organ prolapse quantification stage 3 symptomatic uterine prolapse. The patient requested uterine prolapse repair surgery while retaining the uterus. After performing a posterior colpotomy and entering the posterior cul-de-sac, the alexis and then the GelPOINT V-path transvaginal access platform (Applied Medical, Rancho Santa Margarita, CA) were placed into the vagina. Three trocars were inserted into the port. We used a 10-mm scope with a 30˚-angle view. The instruments included a needle driver and a clinch grasper. The next step was to identify the uterosacral ligamentous structures. Once identified, 2 absorbable vicryl sutures and 1 nonabsorbable Ti-cron suture were placed on each ligament and then secured with large bites into the junctional portion of the uterosacral ligament with the posterior aspect of the cervix. The GelPOINT was then extracted, and the sutures locked in place to shorten the uterosacral ligaments and reinforce their attachment to the cervix. After all the suspensory sutures were tied, cystoscopy was performed to assess ureteral patency. The vaginal incision was then reapproximated in a horizontal manner, using continuous absorbable suture. Conclusion: vNOTES ULH appears to be feasible in women with uterine prolapse when uterus conservative treatment is desired. Advantages of this technique include good exposure of the ureter, lowering the risk of ureteric injury. In addition, the absence of incisions on the abdomen eliminates the risk of abdominal wound infection and incisional pain and yields a better cosmetic outcome. Further studies are needed to appraise the long-term outcomes and demonstrate the ultimate use of this modality.

OBJECTIVE: To evaluate a possible correlation between a new variable—persistent breech presentation—and the success rate of external cephalic version (ECV). METHODS: This was a retrospective study of ECVs performed from January 2008 through January 2019 in an Israeli tertiary care hospital. The study group included all pregnant women who underwent an ECV at or beyond 37 weeks of gestation. Persistent breech presentation was defined as persistent breech presentation during all ultrasound examinations performed between the anatomy scan at mid-pregnancy and the gestational week when ECV was attempted. Women in whom cephalic presentation was documented at least once on these ultrasound examinations were defined as not having persistent breech presentation. The primary outcome was defined as the success rate of ECV, and the secondary outcome was defined as the mode of delivery after a successful ECV. RESULTS: We identified 1,271 women with breech presentation during the study period. They had undergone median of five (range 2–7) ultrasound examinations. External cephalic version was attempted in 684 women (53.8%), with a success rate of 61.5%. External cephalic version succeeded in 19.6% of those with persistent breech presentation (44/224) compared with 82.0% (377/460) of those without persistent breech presentation (P<.001). Ultimately, women with persistent breech presentation and successful ECV experienced a lower rate of vaginal delivery (27.3% vs 79%, P<.001), and a higher rate of instrumental (29% vs 13%, P<.001) and cesarean deliveries (43% vs 7%, P<.001) compared with the nonpersistent breech presentation group. The rate of noninstrumental vaginal delivery among women with persistent breech presentation, regardless of ECV, was 5.4%. CONCLUSION: Women with persistent breech presentation experienced a high rate of ECV failure and a low rate of spontaneous vaginal delivery.