Thirty years' experience with balloon dilation of benign postoperative biliary strictures: long-term outcomes.

PURPOSE: To determine the effectiveness of percutaneous balloon dilation of benign postoperative biliary strictures. MATERIALS AND METHODS: We received approval from our institutional review board to undertake this retrospective HIPAA-compliant study, and informed consent was waived. From April 1, 1977, to April 1, 2007, percutaneous biliary balloon dilation (PBBD) was performed in 85 patients with benign biliary strictures. In the 75 patients with follow-up (31 male, 44 female; mean age, 56 years; mean follow-up, 8 years), 205 PBBD procedures were performed during 112 treatments of 84 biliary strictures. PBBD of the stricture was performed with a noncompliant balloon (8-12-mm diameter). PBBD procedures were repeated at 2- to 14-day intervals until cholangiography demonstrated free drainage of contrast material to the bowel and no residual stenosis. An internal-external biliary drain was left in situ for a mean of 14-22 days and removed after a clinical trial of catheter clamping and a normal cholangiogram. RESULTS: All procedures were technically successful, and 52, 11, 10, and two patients underwent a total of one, two, three, and four PBBD treatments, respectively. Four of 205 procedures (2%) led to major complications: two subphrenic abscesses, one hepatic arterial pseudoaneurysm, and one case of hematobilia treated with transfusion. Six patients died from unrelated causes and three from hepatitis C-related liver failure. The probability of a patient not developing clinically significant restenosis at 5, 10, 15, 20, and 25 years was 0.52, 0.49, 0.49, 0.41, and 0.41, respectively, after the first PBBD treatment and 0.43, 0.30, 0.20, 0.20, and 0.20, respectively, after the second PBBD treatment. No significant difference was found in the rate of clinically significant restenosis after the first PBBD between strictures at anastomotic and nonanastomotic sites (P = .75). During the follow-up period, 56 of 75 patients (75%) had successful management with PBBD. CONCLUSION: PBBD of benign strictures demonstrates long-term effectiveness. No significant difference was found in the rate of clinically significant restenosis after PBBD of biliary strictures at anastomotic and nonanastomotic sites.

The origins of Better Jobs Better Care.

Better Jobs Better Care was the nation's largest single initiative created to reduce the high vacancy and turnover rates of direct care workers and improve workforce quality through both policy and practice changes. In this article, we describe the important role and key characteristics of direct care workers, what motivated the unique partnership between a provider association and a direct care worker advocacy organization to create this initiative, and how the initiative was designed to respond to the key challenges through applied research and demonstration projects. We conclude by discussing how BJBC has influenced providers, policy makers, and direct care workers to think about these frontline caregivers, who are the crux of the long-term care workforce.

Truth cube: establishing physical standards for soft tissue simulation.

Accurate real-time models of soft tissue behavior are key elements in medical simulation systems. The need for fast computation in these simulations, however, often requires simplifications that limit deformation accuracy. Validation of these simplified models remains a challenge. Currently, real-time modeling is at best validated against finite element models that have their own intrinsic limitations. This study develops a physical standard to validate real-time soft tissue deformation models. We took CT images of a cube of silicone rubber with a pattern of embedded Teflon spheres that underwent uniaxial compression and spherical indentation tests. The known material properties, geometry and controlled boundary conditions resulted in a complete set of volumetric displacement data. The results were compared to a finite element model analysis of identical situations. This work has served as a proof of concept for a robust physical standard for use in validating soft tissue models. A web site has been created to provide access to our database: http://biorobotics.harvard.edu/truthcube/ (soon to be http://www.truthcube.org).

Independent testing of soft tissue visco-elasticity using indentation and rotary shear deformations.

Numerous techniques exist to measure the mechanical properties of soft tissues in vivo, such as mechanical stretching, indentation or shearing, as well as elastographic methods employing ultrasound or other imaging modes. Many groups have reported properties which do not necessarily correspond with each other due to differences in choice of technique, tissue model or other variations. This work deliberately makes use of the two independent modes of indentation and rotary shear, on the same material samples, employing similar modeling approximations, to attempt to determine the common, underlying material properties. This paper introduces the ROSA-2 rotary shear instrument, and presents its mechanical characteristics, as well as presenting validation experiments that were performed to verify non-slip contact with tissue. Measurements made with it are compared with those acquired with the TeMPeST l-D indentation instrument. Initial testing showed reasonably agreement when testing silicone gel samples, over a restricted range of frequencies. When testing bovine liver samples in vitro and porcine liver in vivo, significant discrepancies were found. The potential sources of these differences will be discussed, as will directions for ongoing work.