Background: Telestration is an important teaching tool in minimally invasive surgery (MIS). While robotic surgery offers the added benefit of three-dimensional (3-D) visualization, telestration technology does not currently exist for this modality. This project aimed to develop a video algorithm to accurately translate a mentor's two-dimensional (2-D) telestration into a 3-D telestration in the da Vinci visual field.Materials and Methods: A prototype 3-D telestration system was constructed to translate 2-D telestration from a mentor station into 3-D graphics for the trainee at the robotic console. This system uses fast image correlation algorithms to allow 2-D images to be placed over the same anatomic location in the two separate video channels of the stereoscopic robotic visualization system. Three subjects of varying surgical backgrounds, blinded to the mode of telestration (2-D vs. 3-D), were tested in the laboratory, using a simulated robotic task.Results: There were few technologic errors (2), only one of which resulted in a task error, in 99 total trials. Only the experienced MIS staff surgeon had a significantly faster task time in 2-D than in 3-D (P < 0.05). The MIS fellow recorded the fastest task times in 2-D and 3-D (P < 0.05). There were nine task errors, six of which were committed by the MIS fellow. The nonsurgeon trainee had the least number of errors but also had the slowest times.Conclusions: Robotic telestration in 3-D is feasible and does not negatively impact performance in laboratory tasks. We plan to refine the prototype and investigate its use in vivo.

BACKGROUND:One of the most significant limitations of surgical robots has been their inability to allow multiple surgeons and surgeons-in-training to engage in collaborative control of robotic surgical instruments. We report the initial experience with a novel two-headed da Vinci surgical robot that has two collaborative modes: the "swap" mode allows two surgeons to simultaneously operate and actively swap control of the robot's four arms, and the "nudge" mode allows them to share control of two of the robot's arms.MATERIALS AND METHODS:The utility of the mentoring console operating in its two collaborative modes was evaluated through a combination of dry laboratory exercises and animal laboratory surgery. The results from surgeon-resident collaborative performance of complex three-handed surgical tasks were compared to results from single-surgeon and single-resident performance. Statistical significance was determined using Student's t-test.RESULTS:Collaborative surgeon-resident swap control reduced the time to completion of complex three-handed surgical tasks by 25% compared to single-surgeon operation of a four-armed da Vinci (P < 0.01) and by 34% compared to single-resident operation (P < 0.001). While swap mode was found to be most helpful during parts of surgical procedures that require multiple hands (such as isolation and division of vessels), nudge mode was particularly useful for guiding a resident's hands during crucially precise steps of an operation (such as proper placement of stitches).CONCLUSION:The da Vinci mentoring console greatly facilitates surgeon collaboration during robotic surgery and improves the performance of complex surgical tasks. The mentoring console has the potential to improve resident participation in surgical robotics cases, enhance resident education in surgical training programs engaged in surgical robotics, and improve patient safety during robotic surgery.

BACKGROUND: The dawn of laparoscopic surgery and the telecommunications revolution have given birth to the field of telesurgery. METHODS: Even now, surgery is being performed over great distances to bring expert surgical care to physically isolated patients with otherwise limited healthcare access. RESULTS: As technical obstacles are eliminated in the future, telesurgery will extend the reach of military surgeons to patients at sea and on the battlefield, and astronauts will undergo procedures performed by earthbound interventionalists. Just as the Internet has revolutionized the way everyday consumers shop, eventually, telesurgery may transform surgical care, as patients may stay in their local hospitals and simply "dial up" the best telesurgeon for their specific operation. Telesurgical teams have now formed to refine technical approaches to telesurgery, study the effects of telesurgery on human task performance, and establish telesurgery networks around the world. CONCLUSIONS: While some legitimate social, political, and economic issues remain as impediments to the routine practice of telesurgery, there is now no question that telesurgery will play a role in the delivery of surgical care in the twenty-first century.

Objective: To determine the effects of estrone sulfate alone or with different doses of medroxyprogesterone acetate on serum lipid and lipoprotein levels.Methods: A multicenter, double-masked, randomized trial for 1 year involved 682 postmenopausal women, aged 53.8 +/- 0.2 years (mean +/- standard deviation) with intact uteri. Subjects received fixed daily doses of 0.625 mg of estrone sulfate and one of the following regimens: placebo; 2.5 mg daily of medroxyprogesterone acetate; 5 mg daily of medroxyprogesterone acetate; or 10 mg of medroxyprogesterone acetate for the first 12 days of each 28-day cycle. Fasting lipid and lipoprotein levels were measured at baseline and weeks 12, 16, 24, 30, 36, and 52 of treatment. Absolute mean changes from baseline were determined by paired t test, and treatment effects were determined by analysis of variance.Results: Total cholesterol levels decreased significantly (P < .05) from baseline in all study groups; however, reduction was significantly greater (P < .001) in the 2.5-, 5-, and 10-mg groups (-13.3%, -15.2%, and -14.1%) than in the placebo group (-4.9%). Low-density lipoprotein cholesterol levels decreased significantly and equally in all groups (-10.1% to -12.3%). High-density lipoprotein cholesterol levels increased by 3.2% with unopposed estrogen (P < .05) and did not change from baseline with combined therapy. Triglyceride and very low-density lipoprotein cholesterol levels increased by 13.4% and 2.7%, respectively, in the placebo group, did not change in the 2.5-mg group, decreased by 10.2% and 2.0% and by 11.4% and 2.2% in the 5- and 10-mg groups, respectively (P < .05).Conclusion: Estrone sulfate at the daily dose of 0.625 mg alone or with medroxyprogesterone acetate significantly improved lipoprotein levels. Combined therapy with medroxyprogesterone acetate and estrone sulfate was associated with statistically significantly greater reduction in total cholesterol and statistically significantly less increase in triglyceride levels than unopposed estrone sulfate therapy. (C) 2001 by The American College of Obstetricians and Gynecologists.

Dimerization of the molecule of the title compound, [Co(C36H54N2O2)], an efficient dioxygen carrier, is prevented by the methyl and tert-butyl substituents. The square-planar complex is bisected by a crystallographic mirror plane, with disorder of the -CMe2-CMe2-region. Molecular dimensions [Co-O 1.846 (2) and Co-N 1.850 (2) Angstrom] are very similar to those of me related 3-tert-butylsalicylidenato complex.

The utility of the water-soluble (HOCH2)(2)PCH2CH2P(CH2OH)(2) ligand (dhmpe) in generating 19-electron complexes in aqueous solution was tested. in buffered aqueous solutions at pH 2, the ligand reacts with 17-e1ectron radicals generated by photolysis of water-soluble [(CpCH(2)CH(2)NH(3)(+))(2)Mo-2(CO)(6)][NO3-](2) to form 19-electron adducts. The formation of 19-electron adducts was established by disproportionation of [(CpCH(2)CH(2)NH(3)(+))(2)Mo-2(CO)(6)][NO3-](2) and by the reduction of methyl viologen, both standard indicators of 19-electron adduct formation. The crystal structures of the (HOCH2)(2)PCH2CH2P(CH2OH)(2) ligand and of one of its complexes, [Ni(dhmpe)(2)]Cl-2, were determined.

The syntheses of the water-soluble, chelating phosphines 1,2-bis(bis(hydroxybutyl)phosphino)ethane (1, n = 3; DHBuPE) and 1,2-bis(bis(hydroxypentyl)phosphino)ethane (1, n = 4; DHPePE) are reported. These ligands (and, in general, other 1,2-bis(bis(hydroxyalkyl)phosphino)ethane ligands) can be used to impart water solubility to metal complexes. As examples of this, the [Ni(DHPrPE)(2)Cl]Cl (2), [Rh(DHPrPE)(2)][Cl] (3), and [Ru(DHBuPE)(2)Cl(2)][Cl] (4) complexes were synthesized; they are indeed soluble in water (>0.5 M). Crystals of DHPrPE (1, n = 2) are monoclinic, space group P2(1)/c, with a = 9.5935(8) Å, b = 9.353(2) Å, c = 10.655(2) Å, alpha = 90 degrees, beta = 100.03(1) degrees, gamma = 90, V = 941.5(5) Å(3), R = 0.051, and Z = 2. Crystals of [Ni(DHPrPE)(2)Cl]Cl (2) are monoclinic, space group I2, with a = 15.951(3) Å, b = 11.454(2) Å, c = 20.843(3) Å, alpha = 90 degrees, beta = 91.24(2) degrees, gamma = 90 degrees, V = 3807(2) Å(3), R = 0.062, and Z = 4. Crystals of [Rh(DHPrPE)(2)][Cl] (3) are triclinic, space group P&onemacr;, with a = 13.900(2) Å, b = 15.378(2) Å, c = 18.058(2) Å, alpha = 87.71(1) degrees, beta = 75.03(1) degrees, gamma = 85.24(1), V = 3715(2) Å(3), R = 0.044, and Z = 4. Crystals of [Ru(DHBuPE)(2)Cl(2)][Cl] (4) are monoclinic, space group C2/c, with a = 14.310(2) Å, b = 21.630(2) Å, c = 15.459(3) Å, alpha = 90 degrees, beta = 99.83(1) degrees, gamma = 90, V = 4715(1) Å(3), R = 0.056, and Z = 4.