Leiomyosarcoma of the inferior vena cava. Ultrasonographic appearance

Ultrasonographic features of six leiomyosarcomas of the inferior vena cava are described. In most cases, the presentation is typical enough to strongly suggest the histologic diagnosis. The tumor is usually greater than 10 cm long, hypoechoic, heterogeneous. Cystic components can be found. It is sharply demarcated from neighboring organs which are displaced. The mass is located at the very place of the inferior vena cava, the lumen of which is no longer seen. It is fusiform shaped, surprisingly sparing the aorta. Differential diagnosis along with other radiologic examinations, pathologic findings, and prognosis are discussed.     

Short-acting beta-adrenergic blockade and the fetus. A case report.

An infant was born to a woman who received intravenous esmolol for intrapartum supraventricular tachyarrhythmia. Despite the very short acting and cardio-selective beta-1 adrenergic blockade induced by that agent, neonatal effects can occur up to 48 hours after delivery.     

Temporomandibular joint: morphology and signal intensity characteristics of the disk at MR imaging

Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement.     

Mobilization of early hematopoietic progenitor cells with BB-10010: a genetically engineered variant of human macrophage inflammatory protein- 1 alpha

BB-10010 is a genetically engineered variant of human macrophage inflammatory protein-1 alpha with improved solution properties. We show here that it mobilizes stem cells into the peripheral blood. We investigated the mobilizing effects of BB-10010 on the numbers of circulating 8-day spleen colony-forming units (CFU-S8), CFU-S12, and progenitors with marrow repopulating ability (MRA). A single subcutaneous dose of BB-10010 caused a twofold increase in circulating numbers of CFU-S8, CFU-S12, and MRA 30 minutes after dosing. We also investigated the effects of granulocyte colony-stimulating factor (G- CSF) and the combination of G-CSF with BB-10010 on progenitor mobilization. Two days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA progenitors by 25.7-, 19.8-, and 27.7-fold. A single administration of BB-10010 after 2 days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA even further to 38-, 33-, and 100- fold. Splenectomy resulted in increased circulating progenitor numbers but did not change the pattern of mobilization. Two days of treatment with G-CSF then increased circulating CFU-S8, CFU-S12, and MRA by 64-, 69-, and 32-fold. A single BB-10010 administration after G-CSF treatment further increased them to 85-, 117-, and 140-fold, respectively, compared with control. We conclude that BB-10010 causes a rapid increase in the number of circulating hematopoietic progenitors and further enhances the numbers induced by pretreatment with G-CSF. BB- 10010 preferentially mobilized the more primitive progenitors with marrow repopulating activity, releasing four times the number achieved with G-CSF alone. Translated into a clinical setting, this improvement in progenitor cell mobilization may enhance the efficiency of harvest and the quality of grafts for peripheral blood stem cell transplantation.     

Construct validity of nine new inanimate exercises for robotic surgeon training using a standardized setup

Background

As more surgeons choose to complete procedures robotically, validated training tools are needed so that they can acquire and maintain the technical skills required to proficiently use robotic systems. The purpose of this study was to show construct validity of nine new inanimate training exercises for robot-assisted surgery. The inanimate training exercises were designed to span several core technical skills required to use a robotic system.

Methods

New (n = 30) and experienced (n = 11) robotic surgeons participated in the study. New robotic surgeons had not yet completed their first robotic surgery case and participated in this study before attending their robotic certification course. Experienced robotic surgeons had completed more than 200 robotic surgery cases. The raw scores from the exercises were reported so that other research groups could easily define custom proficiency levels. Example normalized scores that could be used in proficiency-based curricula were computed. These normalized scores balanced efficiency (completion time) and accuracy (exercise-specific errors) to measure performance. Finally, the setup was standardized using a custom docking model, which enabled consistent and repeatable completion of the inanimate exercises across surgeons.

Results

For all nine exercises, experienced robotic surgeons completed the exercises significantly faster than new robotic surgeons (p < 0.01). Similarly, experienced robotic surgeons achieved higher normalized scores than new robotic surgeons for all nine exercises (p < 0.01). Finally, consistent robot setup was achieved using the custom docking model based on an analysis of the robot kinematic data.

Conclusions

In summary, all nine inanimate exercises showed construct validity. The results suggest that the inanimate exercises along with the custom docking model can be used as part of proficiency-based curricula to improve robotic surgeon training.