The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Hawkins-Hunter Retrograde Transcutaneous Nephrostomy: A New Technique

Retrograde nephrostomy, a new technique to aid in stone management, has been performed successfully in dogs. It has also been used without complication in a human patient to help remove a renal stone percutaneously under local anesthesia. The technique consists of placing a coaxial catheter over a guidewire under fluoroscopy into the exact calyx desired and advancing a long needle out to the skin to establish a transcutaneous tract. The advantages of the technique include increased control and precision of tract placement, efficient working angles for percutaneous stone removal, and the ability to perform the procedure under local anesthesia

Standardized Measurement of the Future Liver Remnant Prior to Extended Liver Resection: Methodology and Clinical Associations

Background. There is no agreement regarding the preoperative measurement of liver volumes and the minimal safe size of the liver remnant after extended hepatectomy. Methods. In 20 patients with hepatobiliary malignancy and no underlying chronic liver disease, volumetric measurements of the liver remnant (segments 2 and 3 ± 1) were obtained before extended right lobectomy (right trisegmentectomy). The ratios of future liver remnant to total liver volume were calculated by using a formula based on body surface area. In 12 patients, response to preoperative right trisectoral portal vein embolization was evaluated. In 15 patients who underwent the planned resection, preoperative volumes were correlated with biochemical and clinical outcome parameters. Results. The future liver remnants increased after portal vein embolization (26% versus 36%, P < .01). Smaller size liver remnants were associated with an increase in postoperative liver function tests (P < .05) and longer lengths of hospital stay (P < .02). Preliminary data indicates an increase in major complications for liver volumes ≤25% (P = .02). Conclusions. A simple method of measurement provides an assessment of the liver remnant before resection. It is useful in evaluating response to portal vein embolization and in predicating the outcome before extended liver resections. (Surgery 2000;127:512–9.