Science.gov

Sample records for intraoperative warming comparison

  1. Comparison Study of Intraoperative Surface Acquisition Methods for Surgical Navigation

    PubMed Central

    Burgner, Jessica; Glisson, Courtenay L.; Herrell, S. Duke; Ma, Burton; Pheiffer, Thomas S.; Webster, Robert J.; Miga, Michael I.

    2013-01-01

    Soft-tissue image-guided interventions often require the digitization of organ surfaces for providing correspondence from medical images to the physical patient in the operating room. In this paper, the effect of several inexpensive surface acquisition techniques on target registration error and surface registration error (SRE) for soft tissue is investigated. A systematic approach is provided to compare image-to-physical registrations using three different methods of organ spatial digitization: 1) a tracked laser-range scanner (LRS), 2) a tracked pointer, and 3) a tracked conoscopic holography sensor (called a conoprobe). For each digitization method, surfaces of phantoms and biological tissues were acquired and registered to CT image volume counterparts. A comparison among these alignments demonstrated that registration errors were statistically smaller with the conoprobe than the tracked pointer and LRS (p < 0.01). In all acquisitions, the conoprobe outperformed the LRS and tracked pointer: for example, the arithmetic means of the SRE over all data acquisitions with a porcine liver were 1.73 ± 0.77 mm, 3.25 ± 0.78 mm, and 4.44 ± 1.19 mm for the conoprobe, LRS, and tracked pointer, respectively. In a cadaveric kidney specimen, the arithmetic means of the SRE over all trials of the conoprobe and tracked pointer were 1.50 ± 0.50 mm and 3.51 ± 0.82 mm, respectively. Our results suggest that tissue displacements due to contact force and attempts to maintain contact with tissue, compromise registrations that are dependent on data acquired from a tracked surgical instrument and we provide an alternative method (tracked conoscopic holography) of digitizing surfaces for clinical usage. The tracked conoscopic holography device outperforms LRS acquisitions with respect to registration accuracy. PMID:22929367

  2. Comparison of Folate Receptor Targeted Optical Contrast Agents for Intraoperative Molecular Imaging

    PubMed Central

    De Jesus, Elizabeth; Keating, Jane J.; Kularatne, Sumith A.; Jiang, Jack; Judy, Ryan; Predina, Jarrod; Nie, Shuming; Low, Philip; Singhal, Sunil

    2015-01-01

    Background. Intraoperative imaging can identify cancer cells in order to improve resection; thus fluorescent contrast agents have emerged. Our objective was to do a preclinical comparison of two fluorescent dyes, EC17 and OTL38, which both target folate receptor but have different fluorochromes. Materials. HeLa and KB cells lines were used for in vitro and in vivo comparisons of EC17 and OTL38 brightness, sensitivity, pharmacokinetics, and biodistribution. In vivo experiments were then performed in mice. Results. The peak excitation and emission wavelengths of EC17 and OTL38 were 470/520 nm and 774/794 nm, respectively. In vitro, OTL38 required increased incubation time compared to EC17 for maximum fluorescence; however, peak signal-to-background ratio (SBR) was 1.4-fold higher compared to EC17 within 60 minutes (p < 0.001). Additionally, the SBR for detecting smaller quantity of cells was improved with OTL38. In vivo, the mean improvement in SBR of tumors visualized using OTL38 compared to EC17 was 3.3 fold (range 1.48–5.43). Neither dye caused noticeable toxicity in animal studies. Conclusions. In preclinical testing, OTL38 appears to have superior sensitivity and brightness compared to EC17. This coincides with the accepted belief that near infrared (NIR) dyes tend to have less autofluorescence and scattering issues than visible wavelength fluorochromes. PMID:26491562

  3. Comparison of computed tomography, endosonography, and intraoperative assessment in TN staging of gastric carcinoma.

    PubMed Central

    Ziegler, K; Sanft, C; Zimmer, T; Zeitz, M; Felsenberg, D; Stein, H; Germer, C; Deutschmann, C; Riecken, E O

    1993-01-01

    From 1986 to 1990 a prospective comparative study was undertaken to compare the relative accuracy of computed tomography, endogastric ultrasonography, and intraoperative surgical assessment in evaluating the depth of invasion (T category) and involvement of lymph nodes (N category) of patients with gastric carcinoma. One hundred and eight consecutive patients, who were treated by total gastrectomy and previously evaluated with computed tomography, endogastric ultrasonography, and intraoperative surgical assessment, entered the study. Results (T and N category) were compared with those of histopathological staging (pT and pN category). T categories were correctly staged in 43% of cases with computed tomography, 86% with endogastric ultrasonography, and 56% with intraoperative surgical assessment. Computed tomography scanning correctly staged 51% of all N1 and N2 lymph nodes compared with 74% for endogastric ultrasonography and 54% for intraoperative surgical assessment. In general, computed tomography was more accurate for advanced stages of cancer and showed a tendency to overstage the T category and understage N category of gastric tumours. By contrast, endogastric ultrasonography was equally accurate for all T categories and showed an understaging for N categories. Intraoperative surgical assessment overstaged early T stages, understaged T4 tumours, and was equally accurate for all grades of N categories. Computed tomography scanning and intraoperative surgical assessment of T and N categories were of little value in staging of gastric carcinoma. Endogastric ultrasonography is more accurate than computed tomography scanning and intraoperative surgical assessment. Therefore endogastric ultrasonography should be introduced in the preoperative assessment of patients with gastric carcinoma. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8504959

  4. Comparison of intraoperative ultrasonography and cholangiography in detection of small common bile duct stones.

    PubMed Central

    Chardavoyne, R; Kumari-Subhaya, S; Auguste, L J; Phillips, G; Stein, T A; Wise, L

    1987-01-01

    High-resolution intraoperative ultrasonography was compared with conventional radiographic imaging in the detection of small common bile duct (CBD) stones (less than 5 mm in diameter). Sixteen mongrel dogs had laparotomy and ligation of distal CBD; 1 week to 10 days later, 0-3 gallstones of varying sizes (2-5 mm) were introduced into the dilated CBD (6-16 mm). High-resolution intraoperative ultrasonography of the CBD and a conventional intraoperative cholangiogram were performed to detect the presence and number of stones. The results of these two tests were evaluated independently by two ultrasonographers and two surgeons. There were 21 true-positive and five false-negative readings by sonogram compared with 17 and 9, respectively, by cholangiogram. Sensitivity of the sonogram was 81% and 65.4% by cholangiogram. Score of accuracy was 1.06 and 1.62 by cholangiogram and 0.81 and 0.87 by ultrasound (p less than 0.05). Intraoperative ultrasonography was found to be more sensitive in detecting small CBD stones when compared with intraoperative cholangiogram. PMID:3300578

  5. Assessing leg lengths intraoperatively in total hip arthroplasty: comparison of two methods.

    PubMed

    Mehra, Akshay; Moriso, Zachary N; Schemitsch, Emil; Waddell, James

    2013-09-01

    Leg length discrepancy post total hip arthroplasty surgery is common. Unequal leg lengths after total hip arthroplasty is the single most common reason for litigation against orthopaedic surgeons. Different methods for leg length assessment are used intraoperatively by surgeons, but no one method is 100% reliable and reproducible. The aim of this study was to compare 2 methods of intraoperative leg length assessment. Leg length discrepancy of 5 mm or less was achieved in 72.5% (37/51) of patients using method 1 and in 67% (34/51) of patients using method 2. Both methods assessed produced a discrepancy of greater than 5 mm in about a quarter of the patients. The difference was not found to be statistically significant (p < 0.05). Assessment of leg lengths intraoperatively is challenging even for experienced surgeons. The leg lengths may be better restored if more than one method of assessment is used during surgery. PMID:24081845

  6. Intraoperative diagnosis of central nervous system lesions: Comparison of squash smear, touch imprint, and frozen section

    PubMed Central

    Nanarng, Vikram; Jacob, Sunitha; Mahapatra, Debahuti; Mathew, Jacob E

    2015-01-01

    Background: Intraoperative diagnosis of central nervous system (CNS) lesions is of utmost importance for neurosurgeons to modify the approach at the time of surgery and to decide on further plan of management. The intraoperative diagnosis is challenging for neuropathologists. Aims: The study was undertaken to determine the accuracy of cytological techniques (crush smears and touch imprints), frozen sections of space occupying lesions of the CNS and compare it with histopathological diagnosis. Materials and Methods: A total of 75 specimens received intraoperatively were subjected to cytology and frozen section study. Results: Neoplastic lesions formed the major group with 62 (82.7%) cases while 13 (17.3%) were nonneoplastic. The diagnostic accuracy of “squash smears” was found to be 89.2%. “Touch imprints” showed diagnostic accuracy of 78.4%. The low accuracy of touch imprints was attributed to poor cellular yield. The diagnostic accuracy of “frozen section” was 75.7%. However, the overall diagnostic accuracy was 96%. Conclusion: We believe that the cytololgical methods and frozen sections are complimentary to each other and both should be used to improve the intraoperative diagnostic accuracy in the CNS lesion. PMID:26729974

  7. Comparison of Intraoperatively Built Custom Linked Seeds Versus Loose Seed Gun Applicator Technique Using Real-Time Intraoperative Planning for Permanent Prostate Brachytherapy

    SciTech Connect

    Zauls, A. Jason; Ashenafi, Michael S.; Onicescu, Georgiana; Clarke, Harry S.; Marshall, David T.

    2011-11-15

    Purpose: To report our dosimetric results using a novel push-button seed delivery system that constructs custom links of seeds intraoperatively. Methods and Materials: From 2005 to 2007, 43 patients underwent implantation using a gun applicator (GA), and from 2007 to 2008, 48 patientsunderwent implantation with a novel technique allowing creation of intraoperatively built custom links of seeds (IBCL). Specific endpoint analyses were prostate D90% (pD90%), rV100% > 1.3 cc, and overall time under anesthesia. Results: Final analyses included 91 patients, 43 GA and 48 IBCL. Absolute change in pD90% ({Delta}pD90%) between intraoperative and postoperative plans was evaluated. Using GA method, the {Delta}pD90% was -8.1Gy and -12.8Gy for I-125 and Pd-103 implants, respectively. Similarly, the IBCL technique resulted in a {Delta}pD90% of -8.7Gy and -9.8Gy for I-125 and Pd-103 implants, respectively. No statistically significant difference in {Delta}pD90% was found comparing methods. The GA method had two intraoperative and 10 postoperative rV100% >1.3 cc. For IBCL, five intraoperative and eight postoperative plans had rV100% >1.3 cc. For GA, the mean time under anesthesia was 75 min and 87 min for Pd-103 and I-125 implants, respectively. For IBCL, the mean time was 86 and 98 min for Pd-103 and I-125. There was a statistical difference between the methods when comparing mean time under anesthesia. Conclusions: Dosimetrically relevant endpoints were equivalent between the two methods. Currently, time under anesthesia is longer using the IBCL technique but has decreased over time. IBCL is a straightforward brachytherapy technique that can be implemented into clinical practice as an alternative to gun applicators.

  8. Comparison of Preoperative Temporal Bone CT with Intraoperative Findings in Patients with Cholesteatoma

    PubMed Central

    Rogha, Mehrdad; Hashemi, Sayyed Mostafa; Mokhtarinejad, Farhad; Eshaghian, Afrooz; Dadgostar, Alireza

    2014-01-01

    Introduction: Cholesteatoma is traditionally diagnosed by otoscopic examination and treated by surgery. The necessity for imaging in an uncomplicated case is controversial. This study was planned to investigate the usefulness of a preoperative high-resolution computed tomography (HRCT) scan in depicting the status of middle ear structures in the presence of cholesteatoma and also to compare the correspondence between pre- and intraoperative CT findings in patients with cholesteatoma. Materials and Methods: This prospective descriptive study was performed from January 2009 to May 2011 in 36 patients with cholesteatoma who were referred to the Kashani and Al-Zahra Clinics of Otolaryngology. Preoperative high-resolution temporal bone CT scans (axial and coronal views) were carried out and compared with intraoperative findings. Results: Evaluation of 36 patients and their CT scans revealed excellent correlation for sigmoid plate erosion, widening of aditus, and erosion of scutum; good correlation for erosion of malleus and tegmen; moderate correlation for lateral canal fistula (LCF) and erosion of mastoid air cells; and poor correlation for facial nerve dehiscence (FND), incus, and stapes erosion. Conclusion: A preoperative CT scan may be helpful in relation to diagnosis and decision making for surgery in cases of cholesteatoma and ossicular erosion. The CT scan can accurately predict the extent of disease and is helpful for detection of lateral canal fistula, erosions of dural plate, and ossicular erosions. However it is not able to distinguish between cholesteatoma and mucosal disease, facial nerve dehiscency, incus, and stapes erosion. PMID:24505568

  9. Intra-Operative Tissue Oxygen Tension Is Increased by Local Insufflation of Humidified-Warm CO2 during Open Abdominal Surgery in a Rat Model

    PubMed Central

    Marshall, Jean K.; Lindner, Pernilla; Tait, Noel; Maddocks, Tracy; Riepsamen, Angelique; van der Linden, Jan

    2015-01-01

    Introduction Maintenance of high tissue oxygenation (PtO2) is recommended during surgery because PtO2 is highly predictive of surgical site infection and colonic anastomotic leakage. However, surgical site perfusion is often sub-optimal, creating an obstructive hurdle for traditional, systemically applied therapies to maintain or increase surgical site PtO2. This research tested the hypothesis that insufflation of humidified-warm CO2 into the abdominal cavity would increase sub-peritoneal PtO2 during open abdominal surgery. Materials and Methods 15 Wistar rats underwent laparotomy under general anesthesia. Three sets of randomized cross-over experiments were conducted in which the abdominal cavity was subjected to alternating exposure to 1) humidified-warm CO2 & ambient air; 2) humidified-warm CO2 & dry-cold CO2; and 3) dry-cold CO2 & ambient air. Sub-peritoneal PtO2 and tissue temperature were measured with a polarographic oxygen probe. Results Upon insufflation of humidified-warm CO2, PtO2 increased by 29.8 mmHg (SD 13.3; p<0.001), or 96.6% (SD 51.9), and tissue temperature by 3.0°C (SD 1.7 p<0.001), in comparison with exposure to ambient air. Smaller, but significant, increases in PtO2 were seen in experiments 2 and 3. Tissue temperature decreased upon exposure to dry-cold CO2 compared with ambient air (-1.4°C, SD 0.5, p = 0.001). Conclusions In a rat model, insufflation of humidified-warm CO2 into the abdominal cavity during open abdominal surgery causes an immediate and potentially clinically significant increase in PtO2. The effect is an additive result of the delivery of CO2 and avoidance of evaporative cooling via the delivery of the CO2 gas humidified at body temperature. PMID:25835954

  10. Are active warming measures required during paediatric cleft surgeries?

    PubMed Central

    Rajan, Sunil; Halemani, Kusuma Ramachandra; Puthenveettil, Nitu; Baalachandran, Ramasubramanian; Gotluru, Priyanka; Paul, Jerry

    2013-01-01

    Background: During paediatric cleft surgeries intraoperative heat loss is minimal and hence undertaking all possible precautions available to prevent hypothermia and use of active warming measures may result in development of hyperthermia. This study aims to determine whether there will be hyperthermia on active warming and hypothermia if no active warming measures are undertaken. The rate of intraoperative temperature changes with and without active warming was also noted. Methods: This study was conducted on 120 paediatric patients undergoing cleft lip and palate surgeries. In Group A, forced air warming at 38°C was started after induction. In Group B, no active warming was done. Body temperature was recorded every 30 min starting after induction until 180 min or end of surgery. Intragroup comparison of variables was done using Paired sample test and intergroup comparison using independent sample t-test. Results: In Group A, all intraoperative temperature readings were significantly higher than baseline. In Group B, there was a significant reduction in temperature at 30 and 60 min. Temperature at 90 min did not show any significant difference, but further readings were significantly higher. Maximum rise in temperature occurred in Group A between 120 and 150 min and maximum fall in temperature in Group B was seen during first 30 min. Conclusion: In pediatric cleft surgeries, we recommend active warming during the first 30 minutes if the surgery is expected to last for <2h, and no such measures are required if the expected duration is >2h. PMID:24163452

  11. [Postoperative warming therapy in the recovery room. A comparison of radiative and convective warmers].

    PubMed

    Weyland, W; Fritz, U; Fabian, S; Jaeger, H; Crozier, T; Kietzmann, D; Braun, U

    1994-10-01

    Hypothermia (Tcore < 36 degrees C) can be observed in 60%-80% of all admissions to the post-anaesthetic recovery unit. Effective warming devices may accelerate rewarming, improve patient comfort, and suppress shivering thermogenesis. This study was designed to compare the efficiency of warming devices in extubated postoperative patients and their effect on postoperative oxygen uptake (VO2). METHODS. Thirty-five ASA I and II patients after laparoscopic hernioplastic repair with core temperatures < 36 degrees C were randomly assigned to either postoperative nursing under a radiant heater (group R, n = 11, Aragona Thermal Ceilings CTC X, Aragona Medical AB, Täby, Sweden), a forced air system (group L, n = 12, Bair Hugger, Augustine Medical Inc., Eden Prairie, Minnesota, USA), or a normal cotton hospital blanket (group K, n = 12). Anaesthesia was conducted totally intravenously with propofol, alfentanil, and vecuronium. Mean body temperature and total body heat were calculated from urinary bladder temperature and four subcutaneous temperature measurements. The rate of thermogenesis was calculated from continuous measurement of VO2 (Datex Deltatrac Metabolic Monitor, Datex Instrumentarium Corp., Helsinki, Finland). Heat balance was derived from the increase in total body heat minus body heat production. Heart rate and noninvasive blood pressure were measured by the Cardiocap (Datex Instrumentarium Corp., Helsinki, Finland). All data were transferred to an IBM-compatible computer at 60-s intervals. Measurements were stopped when core temperature reached 37 degrees C. The rate of change was calculated for each variable for the period 15 min after the beginning of rewarming to attainment of 37 degrees C. Data are presented as median, minima, and maxima (min<==>max); the Mann-Whitney U test was used to test for significance of group differences. RESULTS. All groups were comparable for body weight, height, age, and amount of postoperative infusions. Temperatures at admission were 35.2 (33.4<==>35.9), 34.7 (34.3<==>35.8), and 35.4 (34.3<==>35.9) degrees C for groups R, B, and K, respectively. No significant differences in the rate of central rewarming could be found for these groups with 0.81 (0.41<==>1.32), 0.76 (0.40<==>1.07), and 0.70 (0.37<==>1.13) degrees C/h (Fig. 1). The mean VO2 of 3.41 (3.07<==>3.73), 3.55 (2.78<==>4.06), and 3.79 (2.51<==>7.00) ml/kg/min also did not differ significantly (Fig. 3). Significant differences between groups R and B [4.39 (3.74<==>6.19) and 4.30 (3.46<==>6.67) ml/kg/min] and K [5.92 (3.79<==>10.64) ml/kg/min] were found for VO2 maxima during the course of investigation (Fig. 4). The heat balance revealed significant differences among treatment and control groups with -88 (-226<==>+30), -41 (-212<==>+12), and -191 (-265<==>-86) kJ/h for groups R, B, and K. We additionally calculated the heat balance as a quotient, which showed 0.70 (0.22<==>1.07), 0.86 (0.44<==>1.04), and 0.49 (0.31<==>0.79) for groups R, B, and K (Fig. 4). The mean rate-pressure product of all groups did not differ significantly during the period of investigation. CONCLUSIONS. Neither external heat supply by radiant heat nor by a forced warm air system significantly reduced rewarming time in extubated, awake patients. As measured by heat balance, both active treatments saved about 20% more body heat production than in the control group. Continuing peripheral vasoconstriction may be the reason for the low efficiency of heat transfer. Thermal treatment did reduce the peak load (max. VO2) on the oxygen transport systems, though shivering was treated by pethidine if it occurred. External rewarming did not reduce the average load (mean VO2). Thus, concerning the goal of accelerating rewarming, it appears more rational to prevent intraoperative heat loss. For a comparison of efficiency of different warming devices, postoperative extubated patients do not appear to be an ideal model for study. PMID:7818046

  12. Comparison of implant quality between loose and intra-operatively linked iodine-125 seeds in prostate cancer brachytherapy.

    PubMed

    Jarusevicius, Laimonas; Inciura, Arturas; Juozaityte, Elona; Vaiciunas, Kestutis; Vaitkus, Antanas; Sniureviciute, Migle

    2012-01-01

    From 2007 to 2010, 230 patients had iodine-125 seeds implanted (loose or intra-operatively linked into seed trains with variable seed-to-seed spacing). The primary aim was to evaluate differences in implant quality by comparing the intra-operative and post-implant dosimetry in patients treated with loose and intra-operatively linked seeds. The secondary aim was to evaluate the "learning curve" for the procedure. The following parameters were compared: the radiation dose to 90% of the prostate volume (D90), the radiation dose to 30% of the urethral volume (DU30), the percentage of the prostate volume receiving 100% or 200% of the prescribed dose (V100 or V200, respectively), the percentage of the rectal volume receiving 100% of the prescribed dose (VR100), and the homogeneity index (HI). We obtained the following results for loose vs. intra-operatively linked seeds: D90 (Gy), 184.7 ± 15.0 vs. 177.9 ± 12.7 (p = 0.002); V100 (%), 95.5 ± 2.4 vs. 94.9 ± 3.2 (p = 0.206); V200 (%), 35.1 ± 7.5 vs. 24.3 plusmn; 6,9 (p < 0.001); DU30 (Gy), 218.6 ± 24.1 vs. 197.4 ± 19.5 (p = 0.001); VR100 (cm³), 0.6 ± 0.47 vs. 0.3 ± 0.3 (p < 0.001); HI (%), 31.8 ± 7.3 vs. 44.0 ± 9.8 (p < 0.001). The advantages of intra-operatively linked seed implantation over loose seed implantation are a more homogeneous prostate dose and lower urethral and rectal doses. The disadvantage is a lower post-implant D90. Sufficient experience with the loose seed implantation procedure was obtained after the first 40 patients. There was essentially no learning curve when a new implantation method using intra-operatively linked seeds was subsequently initiated. PMID:22739013

  13. Comparison of Effects of Labetalol and Nitroglycerine on Intraoperative Blood Loss and Surgical Field Quality in Rhinoplasty Surgery

    PubMed Central

    Hadavi, Mohamad Reza; Zarei, Yadollah; Tarogh, Shojaolhagh

    2015-01-01

    BACKGROUND Rhinoplasty is one of the most common surgeries of the plastic surgery and as well as ear, throat and nose. Intra-operative bleeding during surgery is one of the most important factors that may impair the surgeon’s job. Providing a clean blood-free surgical filed makes the operation faster, easier and with a better quality. One way to achieve this goal is to induce hypotension. This study aimed to compare the impacts and outcomes of administration of labetalol or nitroglycerin for this purpose. METHODS In this randomized clinical trial, 60 ASA I and ASA II patients who were referred for rhinoplasty were enrolled. Patients were randomly assigned to two groups. Labetalol was given to the first and nitroglycerin to the second group of patients. Blood pressure and the amount of intra-operative bleeding during surgery and surgeon satisfaction were measured. RESULTS The average age of patients was 25.9±7.52 years. The average amount of bleeding among all patients was 117.87±324.86 ml, and the average quality of the surgical site was 1.65±4.48, considering all patients. The average quality and average surgical site bleeding between the two groups was not significant. CONCLUSION There was a little difference between labetalol and nitroglycerine on the effect of intraoperative blood loss and surgical field quality in rhinoplasty surgery. PMID:25606478

  14. Comparison of electron transport calculations in warm dense matter using the Ziman formula

    DOE PAGESBeta

    Burrill, D. J.; Feinblum, D. V.; Charest, M. R. J.; Starrett, C. E.

    2016-02-10

    The Ziman formulation of electrical conductivity is tested in warm and hot dense matter using the pseudo-atom molecular dynamics method. Several implementation options that have been widely used in the literature are systematically tested through a comparison to the accurate, but expensive Kohn–Sham density functional theory molecular dynamics (KS-DFT-MD) calculations. As a result, the comparison is made for several elements and mixtures and for a wide range of temperatures and densities, and reveals a preferred method that generally gives very good agreement with the KS-DFT-MD results, but at a fraction of the computational cost.

  15. Comparison of electron transport calculations in warm dense matter using the Ziman formula

    NASA Astrophysics Data System (ADS)

    Burrill, D. J.; Feinblum, D. V.; Charest, M. R. J.; Starrett, C. E.

    2016-06-01

    The Ziman formulation of electrical conductivity is tested in warm and hot dense matter using the pseudo-atom molecular dynamics method. Several implementation options that have been widely used in the literature are systematically tested through a comparison to the accurate, but expensive Kohn-Sham density functional theory molecular dynamics (KS-DFT-MD) calculations. The comparison is made for several elements and mixtures and for a wide range of temperatures and densities, and reveals a preferred method that generally gives very good agreement with the KS-DFT-MD results, but at a fraction of the computational cost.

  16. Simulations of the February 1979 stratospheric sudden warming: Model comparisons and three-dimensional evolution

    SciTech Connect

    Manney, G.L. ); Farrara, J.D.; Mechoso, C.R. )

    1994-06-01

    The evolution of the stratospheric flow during the major stratospheric sudden warming of February 1979 is studied using two primitive equation models of the stratosphere and mesosphere. The United Kingdom Meteorological Office Stratosphere-Mesosphere Model (SMM) uses log pressure as a vertical coordinate. A spectral, entropy coordinate version of the SMM (entropy coordinate model, or ECM) that has recently been developed is also used. The ECM produces a more realistic recombination and recovery of the polar vortex in the midstratosphere after the warming. Comparison of SMM simulations with forecasts performed using the University of California, Los Angeles general circulation model confirms the previously noted sensitivity of stratospheric forecasts to tropospheric forecast and emphasizes the importance of adequate vertical resolution in modeling the stratosphere. The ECM simulations provide a schematic description of the three-dimensional evolution of the polar vortex and the motion of air through it. During the warming, the two cyclonic vortices tilt westward and equatorward with height. Strong upward velocities develop in the lower stratosphere on the west (cold) side of a baroclinic zone as it forms over Europe and Asia. Strong downward velocities appear in the upper stratosphere on the east (warm) side, strengthening the temperature gradients. After the peak of the warming, vertical velocities decrease, downward velocities move into the lower stratosphere, and upward velocities move into the upper stratosphere. Transport calculations show that air with high ozone mixing ratios is advected toward the pole from low latitudes during the warming, and air with low ozone mixing ratios is transported to the midstratosphere from both higher and lower altitudes along the baroclinic zone in the polar regions. 32 refs., 23 figs., 1 tab.

  17. Simulations of the February 1979 stratospheric sudden warming: Model comparisons and three-dimensional evolution

    NASA Technical Reports Server (NTRS)

    Manney, G. L.; Farrara, J. D.; Mechoso, C. R.

    1994-01-01

    The evolution of the stratopsheric flow during the major stratospheric sudden warming of February 1979 is studied using two primitive equation models of the stratosphere and mesosphere. The United Kingdom Meteorological Office Stratosphere-Mesosphere Model (SMM) uses log pressure as a vertical coordinate. A spectral, entropy coordinate version of the SMM (entropy coordinate model, or ECM) that has recently been developed is also used. Comparison of SMM simulations with forecasts performed using the University of California, Los Angeles general circulation model confirms the previously noted sensitivity of stratospheric forecasts to tropospheric forecasts and emphasizes the importance of adequate vertical resolution in modeling the stratosphere. The ECM simulations provide a schematic description of the three-dimensional evolution of the polar vortex and the motion of air through it. During the warming, the two cyclonic vortices tilt westward and equatorward with height. Strong upward velocities develop in the lower stratosphere on the west (cold) side of a baroclinic zone as it forms over Europe and Asia. Strong downward velocities appear in the upper stratosphere on the east (warm) side, strengthening the temperature gradients. After the peak of the warming, vertical velocities decrease, downward velocities move into the lower stratosphere, and upward velocities move into the upper stratosphere.

  18. Comparison of intra-operative analgesia provided by intravenous regional anesthesia or brachial plexus block for pancarpal arthrodesis in dogs.

    PubMed

    De Marzo, C; Crovace, A; De Monte, V; Grimaldi, D; Iarussi, F; Staffieri, F

    2012-12-01

    The aim of this study was to compare intravenous regional anesthesia (IVRA) and brachial plexus block (BPB) for intra-operative analgesia in dogs undergoing pancarpal arthrodesis (PA). Twenty dogs scheduled for PA were intramuscularly sedated with acepromazine (0.03 mg/kg), general anesthesia was intravenously (IV) induced with thiopental (10 mg/kg) and, after intubation, maintained with isoflurane in oxygen. In 10 dogs (GIVRA) IVRA was performed on the injured limb administering 0.6 ml/kg of 0.5% lidocaine. In 10 dogs (GBPB) the BPB was performed at the axillary level with the help of a nerve stimulator and 0.3 ml/kg of a 1:1 solution of 2% lidocaine and 1% ropivacaine was injected. During surgery fentanyl (0.002 mg/kg IV) was administered if there was a 15% increase of HR and/or MAP compared to the values before surgical stimulation. All the standard cardiovascular and respiratory parameters were continuously monitored during surgery. The duration of surgery and the time of extubation were recorded. Data were compared with a 1-way ANOVA test (P<0.05). No patients required fentanyl administration during surgery. All the recorded parameters were similar in the two groups. The two techniques were similar in providing intra-operative analgesia in dogs undergoing orthopaedic surgery. PMID:22464864

  19. A Lagrangian analysis of a sudden stratospheric warming - Comparison of a model simulation and LIMS observations

    NASA Technical Reports Server (NTRS)

    Pierce, R. B.; Remsberg, Ellis E.; Fairlie, T. D.; Blackshear, W. T.; Grose, William L.; Turner, Richard E.

    1992-01-01

    Lagrangian area diagnostics and trajectory techniques are used to investigate the radiative and dynamical characteristics of a spontaneous sudden warming which occurred during a 2-yr Langley Research Center model simulation. The ability of the Langley Research Center GCM to simulate the major features of the stratospheric circulation during such highly disturbed periods is illustrated by comparison of the simulated warming to the observed circulation during the LIMS observation period. The apparent sink of vortex area associated with Rossby wave-breaking accounts for the majority of the reduction of the size of the vortex and also acts to offset the radiatively driven increase in the area occupied by the 'surf zone'. Trajectory analysis of selected material lines substantiates the conclusions from the area diagnostics.

  20. How warm was the last interglacial? New model-data comparisons.

    PubMed

    Otto-Bliesner, Bette L; Rosenbloom, Nan; Stone, Emma J; McKay, Nicholas P; Lunt, Daniel J; Brady, Esther C; Overpeck, Jonathan T

    2013-10-28

    A Community Climate System Model, Version 3 (CCSM3) simulation for 125 ka during the Last Interglacial (LIG) is compared to two recent proxy reconstructions to evaluate surface temperature changes from modern times. The dominant forcing change from modern, the orbital forcing, modified the incoming solar insolation at the top of the atmosphere, resulting in large positive anomalies in boreal summer. Greenhouse gas concentrations are similar to those of the pre-industrial (PI) Holocene. CCSM3 simulates an enhanced seasonal cycle over the Northern Hemisphere continents with warming most developed during boreal summer. In addition, year-round warming over the North Atlantic is associated with a seasonal memory of sea ice retreat in CCSM3, which extends the effects of positive summer insolation anomalies on the high-latitude oceans to winter months. The simulated Arctic terrestrial annual warming, though, is much less than the observational evidence, suggesting either missing feedbacks in the simulation and/or interpretation of the proxies. Over Antarctica, CCSM3 cannot reproduce the large LIG warming recorded by the Antarctic ice cores, even with simulations designed to consider observed evidence of early LIG warmth in Southern Ocean and Antarctica records and the possible disintegration of the West Antarctic Ice Sheet. Comparisons with a HadCM3 simulation indicate that sea ice is important for understanding model polar responses. Overall, the models simulate little global annual surface temperature change, while the proxy reconstructions suggest a global annual warming at LIG (as compared to the PI Holocene) of approximately 1(°)C, though with possible spatial sampling biases. The CCSM3 SRES B1 (low scenario) future projections suggest high-latitude warmth similar to that reconstructed for the LIG may be exceeded before the end of this century. PMID:24043870

  1. Comparison of Real-Time Intraoperative Ultrasound-Based Dosimetry With Postoperative Computed Tomography-Based Dosimetry for Prostate Brachytherapy

    SciTech Connect

    Nag, Subir; Shi Peipei; Liu Bingren; Gupta, Nilendu; Bahnson, Robert R.; Wang, Jian Z.

    2008-01-01

    Purpose: To evaluate whether real-time intraoperative ultrasound (US)-based dosimetry can replace conventional postoperative computed tomography (CT)-based dosimetry in prostate brachytherapy. Methods and Materials: Between December 2001 and November 2002, 82 patients underwent {sup 103}Pd prostate brachytherapy. An interplant treatment planning system was used for real-time intraoperative transrectal US-guided treatment planning. The dose distribution was updated according to the estimated seed position to obtain the dose-volume histograms. Postoperative CT-based dosimetry was performed a few hours later using the Theraplan-Plus treatment planning system. The dosimetric parameters obtained from the two imaging modalities were compared. Results: The results of this study revealed correlations between the US- and CT-based dosimetry. However, large variations were found in the implant-quality parameters of the two modalities, including the doses covering 100%, 90%, and 80% of the prostate volume and prostate volumes covered by 100%, 150%, and 200% of the prescription dose. The mean relative difference was 38% and 16% for doses covering 100% and 90% of the prostate volume and 10% and 21% for prostate volumes covered by 100% and 150% of the prescription dose, respectively. The CT-based volume covered by 200% of the prescription dose was about 30% greater than the US-based one. Compared with CT-based dosimetry, US-based dosimetry significantly underestimated the dose to normal organs, especially for the rectum. The average US-based maximal dose and volume covered by 100% of the prescription dose for the rectum was 72 Gy and 0.01 cm{sup 3}, respectively, much lower than the 159 Gy and 0.65 cm{sup 3} obtained using CT-based dosimetry. Conclusion: Although dosimetry using intraoperative US-based planning provides preliminary real-time information, it does not accurately reflect the postoperative CT-based dosimetry. Until studies have determined whether US-based dosimetry or postoperative CT-based dosimetry can better predict patient outcomes, the American Brachytherapy Society recommendation of CT-based postimplant dosimetry should remain the standard of care.

  2. Comparison of dexmedetomidine with fentanyl for maintenance of intraoperative hemodynamics in hypertensive patients undergoing major surgery: A randomized controlled trial

    PubMed Central

    Bilgi, Kanchan V.; Vasudevan, Arumugam; Bidkar, Prasanna Udupi

    2016-01-01

    Background: The objective of this study was to study and compare the effects of intravenous dexmedetomidine and fentanyl on intraoperative hemodynamics, opioid consumption, and recovery characteristics in hypertensive patients. Methods: Fifty-seven hypertensive patients undergoing major surgery were randomized into two groups, Group D (dexmedetomidine, n = 29) and Group F (fentanyl, n = 28). The patients received 1 μg/kg of either dexmedetomidine or fentanyl, followed by 0.5 μg/kg/h infusion of the same drug, followed by a standard induction protocol. Heart rate (HR), mean arterial pressures (MAPs), end-tidal isoflurane concentration, and use of additional fentanyl and vasopressors were recorded throughout. Results: Both dexmedetomidine and fentanyl caused significant fall in HR and MAP after induction and dexmedetomidine significantly reduced the induction dose of thiopentone (P = 0.026). After laryngoscopy and intubation, patients in Group D experienced a fall in HR and a small rise in MAP (P = 0.094) while those in Group F showed significant rise in HR (P = 0.01) and MAP (P = 0.004). The requirement of isoflurane and fentanyl boluses was significantly less in Group D. The duration of postoperative analgesia was longer in Group D (P = 0.015) with significantly lower postoperative nausea and vomiting (PONV) (P < 0.001). Conclusion: Infusion of dexmedetomidine in hypertensive patients controlled the sympathetic stress response better than fentanyl and provided stable intraoperative hemodynamics. It reduced the dose of thiopentone, requirement of isoflurane and fentanyl boluses. The postoperative analgesia was prolonged, and incidence of PONV was less in patients who received dexmedetomidine. PMID:27212770

  3. A Prospective Quasi-Randomized Comparison of Intraoperatively Built Custom-Linked Seeds Versus Loose Seeds for Prostate Brachytherapy

    SciTech Connect

    Ishiyama, Hiromichi; Satoh, Takefumi; Kawakami, Shogo; Tsumura, Hideyasu; Komori, Shouko; Tabata, Ken-ichi; Sekiguchi, Akane; Takahashi, Ryo; Soda, Itaru; Takenaka, Kouji; Iwamura, Masatsugu; Hayakawa, Kazushige

    2014-09-01

    Purpose: To compare dosimetric parameters, seed migration rates, operation times, and acute toxicities of intraoperatively built custom-linked (IBCL) seeds with those of loose seeds for prostate brachytherapy. Methods and Materials: Participants were 140 patients with low or intermediate prostate cancer prospectively allocated to an IBCL seed group (n=74) or a loose seed group (n=66), using quasirandomization (allocated by week of the month). All patients underwent prostate brachytherapy using an interactive plan technique. Computed tomography and plain radiography were performed the next day and 1 month after brachytherapy. The primary endpoint was detection of a 5% difference in dose to 90% of prostate volume on postimplant computed tomography 1 month after treatment. Seed migration was defined as a seed position >1 cm from the cluster of other seeds on radiography. A seed dropped into the seminal vesicle was also defined as a migrated seed. Results: Dosimetric parameters including the primary endpoint did not differ significantly between groups, but seed migration rate was significantly lower in the IBCL seed group (0%) than in the loose seed group (55%; P<.001). Mean operation time was slightly but significantly longer in the IBCL seed group (57 min) than in the loose seed group (50 min; P<.001). No significant differences in acute toxicities were seen between groups (median follow-up, 9 months). Conclusions: This prospective quasirandomized control trial showed no dosimetric differences between IBCL seed and loose seed groups. However, a strong trend toward decreased postimplant seed migration was shown in the IBCL seed group.

  4. Comparison of global warming impacts of automobile air-conditioning concepts

    SciTech Connect

    1995-12-31

    The global warming impacts of conventional vapor compression automobile air conditioning using HFC-134a are compared with the potential impacts of four alternative concepts. Comparisons are made on the basis of total equivalent warming impact (TEWI) which accounts for the effects of refrigerant emissions, energy use to provide comfort cooling, and fuel consumed to transport the weight of the air conditioning system. Under the most favorable assumptions on efficiency and weight, transcritical compression using CO{sub 2} as the refrigerant and adsorption cooling with water and zeolite beds could reduce TEWI by up to 18%rlative to HFC-134a compression air conditioning. Other assumptions on weight and efficiency lead to significant increases in TEWI relative to HFC-134a, and it is impossible to determine which set of assumptios is valid from existing data, Neither Stirling cycle or thermoelectric cooling will reduce TEWI relative to EFC-134a. Brief comments are also made concerning technical barriers that must be overcome for succesful development of the new technologies.

  5. Predictability of the stratospheric sudden warming and its impact on the tropospheric climate in January 2009 -Comparison with the warmings of 2004 and 2006-

    NASA Astrophysics Data System (ADS)

    Kuroda, Y.

    2010-12-01

    Predictability of the stratospheric sudden warming (SSW) and its following Northern Annular Mode (NAM) variability in the troposphere is examined for the winter of 2009, and comparison is made with other warmings of 2004 and 2006. The predictability was examined using sets of ensemble runs of a climate model of our institute. The SSW of 2009 is very unusual in the sense that it is caused by almost pure planetary wave of zonal-wavenumber 2 and such SSW is the only one that appears in the past. So it will be interesting to see how extend can we predict the occurrence of the SSW and following impact on the troposphere with the climate model. The result shows that the occurrence of the SSW can be predicted if prediction is initialized within 8 days before the peaked day. The limit is rather short compared with the one found in the previous studies, which shows limit longer than about 2 weeks. The predictability of the downward propagating tropospheric NAM variability following the SSW shows that very long predictability of a few months cannot be obtained even if the forecast is performed before the occurrence of the SSW. Predictability is limited to almost half months regardless of the initial time of the prediction. The situation was very different to the typical PJO-type warmings of 2004 and 2006.

  6. Comparison of the findings on preoperative dipyridamole perfusion scintigraphy and intraoperative transesophageal echocardiography: Implications regarding the identification of myocardium at ischemic risk

    SciTech Connect

    Watters, T.A.; Botvinick, E.H.; Dae, M.W.; Cahalan, M.; Urbanowicz, J.; Benefiel, D.J.; Schiller, N.B.; Goldstone, G.; Reilly, L.; Stoney, R.J. )

    1991-07-01

    The evidence of myocardium at potential ischemic risk on preoperative dipyridamole perfusion scintigraphy was compared with that of manifest ischemia on intraoperative transesophageal echocardiography in 26 patients at high risk of a coronary event undergoing noncardiac surgery. The clinical outcome was also assessed. Induced intraoperative wall motion abnormalities were more common in patients and myocardial segments with, than in those without, a preoperative reversible perfusion defect (both p less than 0.05). Conversely, a preoperative reversible perfusion defect was more common in patients and segments with, than in those without, a new intraoperative wall motion abnormality (both p less than 0.05). Six patients, five with a reversible scintigraphic defect but only three with a new wall motion abnormality, had a hard perioperative ischemic event. Events occurred more often among patients with, than in those without, a reversible perioperative scintigraphic defect (5 (33%) of 15 vs. 1 (9%) of 11) but this difference did not reach significance (p = 0.14), probably owing to the sample size. Intraoperative wall motion abnormalities were all reversible and did not differentiate between risk groups; these findings were possibly influenced by treatment. These preliminary data support the known relation between reversible scintigraphic defects and perioperative events and identify another manifestation of ischemic risk in the relation between reversible scintigraphic defects and induced intraoperative wall motion abnormalities. The value of intraoperative echocardiography in identifying ischemia and guiding therapy in patients with a reversible scintigraphic abnormality should be further assessed.

  7. Comparison of isokinetic muscle strength and muscle power by types of warm-up.

    PubMed

    Sim, Young-Je; Byun, Yong-Hyun; Yoo, Jaehyun

    2015-05-01

    [Purpose] The purpose of this study was to clarify the influence of static stretching at warm-up on the isokinetic muscle torque (at 60°/sec) and muscle power (at 180°/sec) of the flexor muscle and extensor muscle of the knee joint. [Subjects and Methods] The subjects of this study were 10 healthy students with no medically specific findings. The warm-up group and warm-up with stretching group performed their respective warm-up prior to the isokinetic muscle torque evaluation of the knee joint. One-way ANOVA was performed by randomized block design for each variable. [Results] The results were as follows: First, the flexor peak torque and extensor peak torque of the knee joint tended to decrease at 60°/sec in the warm-up with stretching group compared with the control group and warm-up group, but without statistical significance. Second, extensor power at 180°/sec was also not statistically significant. However, it was found that flexor power increased significantly in the warm-up with stretching group at 180°/sec compared with the control group and warm-up group in which stretching was not performed. [Conclusion] Therefore, it is considered that in healthy adults, warm-up including two sets of stretching for 20 seconds per muscle group does not decrease muscle strength and muscle power. PMID:26157247

  8. Weather Research and Forecasting Model Sensitivity Comparisons for Warm Season Convective Initiation

    NASA Technical Reports Server (NTRS)

    Watson, Leela R.; Hoeth, Brian; Blottman, Peter F.

    2007-01-01

    Mesoscale weather conditions can significantly affect the space launch and landing operations at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS). During the summer months, land-sea interactions that occur across KSC and CCAFS lead to the formation of a sea breeze, which can then spawn deep convection. These convective processes often last 60 minutes or less and pose a significant challenge to the forecasters at the National Weather Service (NWS) Spaceflight Meteorology Group (SMG). The main challenge is that a "GO" forecast for thunderstorms and precipitation is required at the 90 minute deorbit decision for End Of Mission (EOM) and at the 30 minute Return To Launch Site (RTLS) decision at the Shuttle Landing Facility. Convective initiation, timing, and mode also present a forecast challenge for the NWS in Melbourne, FL (MLB). The NWS MLB issues such tactical forecast information as Terminal Aerodrome Forecasts (TAFs), Spot Forecasts for fire weather and hazardous materials incident support, and severe/hazardous weather Watches, Warnings, and Advisories. Lastly, these forecasting challenges can also affect the 45th Weather Squadron (45 WS), which provides comprehensive weather forecasts for shuttle launch, as well as ground operations, at KSC and CCAFS. The need for accurate mesoscale model forecasts to aid in their decision making is crucial. Both the SMG and the MLB are currently implementing the Weather Research and Forecasting Environmental Modeling System (WRF EMS) software into their operations. The WRF EMS software allows users to employ both dynamical cores - the Advanced Research WRF (ARW) and the Non-hydrostatic Mesoscale Model (NMM). There are also data assimilation analysis packages available for the initialization of the WRF model- the Local Analysis and Prediction System (LAPS) and the Advanced Regional Prediction System (ARPS) Data Analysis System (ADAS). Having a series of initialization options and WRF cores, as well as many options within each core, provides SMG and NWS MLB with a lot of flexibility. It also creates challenges, such as determining which configuration options are best to address specific forecast concerns. The goal of this project is to assess the different configurations available and to determine which configuration will best predict warm season convective initiation in East-Central Florida. Four different combinations of WRF initializations will be run (ADAS-ARW, ADAS-NMM, LAPS-ARW, and LAPS-NMM) at a 4-km resolution over the Florida peninsula and adjacent coastal waters. Five candidate convective initiation days using three different flow regimes over East-Central Florida will be examined, as well as two null cases (non-convection days). Each model run will be integrated 12 hours with three runs per day, at 0900, 1200, and 1500 UTe. ADAS analyses will be generated every 30 minutes using Level II Weather Surveillance Radar-1988 Doppler (WSR-88D) data from all Florida radars to verify the convection forecast. These analyses will be run on the same domain as the four model configurations. To quantify model performance, model output will be subjectively compared to the ADAS analyses of convection to determine forecast accuracy. In addition, a subjective comparison of the performance of the ARW using a high-resolution local grid with 2-way nesting, I-way nesting, and no nesting will be made for select convective initiation cases. The inner grid will cover the East-Central Florida region at a resolution of 1.33 km. The authors will summarize the relative skill of the various WRF configurations and how each configuration behaves relative to the others, as well as determine the best model configuration for predicting warm season convective initiation over East-Central Florida.

  9. Intraoperative Stem Cell Therapy

    PubMed Central

    Coelho, Mónica Beato; Cabral, Joaquim M.S.; Karp, Jeffrey M.

    2013-01-01

    Stem cells hold significant promise for regeneration of tissue defects and disease-modifying therapies. Although numerous promising stem cell approaches are advancing in clinical trials, intraoperative stem cell therapies offer more immediate hope by integrating an autologous cell source with a well-established surgical intervention in a single procedure. Herein, the major developments in intraoperative stem cell approaches, from in vivo models to clinical studies, are reviewed, and the potential regenerative mechanisms and the roles of different cell populations in the regeneration process are discussed. Although intraoperative stem cell therapies have been shown to be safe and effective for several indications, there are still critical challenges to be tackled prior to adoption into the standard surgical armamentarium. PMID:22809140

  10. Monitoring for intraoperative awareness.

    PubMed

    Ouellette, S M; Simpson, C

    1998-12-01

    Despite advances in anesthetic technique and technology, intraoperative awareness continues to occur with alarming regularity. The psychological effects on patients and the medicolegal consequences to providers have created the need for a reliable monitor of the hypnotic component of anesthesia. A new technology known as bispectral analysis (BIS) has the potential to put an end to the devastating occurrence of intraoperative awareness, as well as improve the overall effectiveness of anesthetic delivery and the surgical experience. Applicable to almost any situation requiring sedation or general anesthesia, BIS's reliability is a real-time measure of hypnosis levels. PMID:9864589

  11. Intraoperative custom press-fit and standard press-fit femoral components in total hip arthroplasty. A comparison of surgery, charges, and early complications.

    PubMed

    Mathur, S K; Mont, M A; McCutchen, J W

    1996-07-01

    A consecutive group of 60 patients who had intraoperative custom press-fit total hip arthroplasties (67 hips; Identifit, Thackray, London, United Kingdom) was compared with a similar group of 60 patients who had standard press-fit arthroplasties (66 hips; McCutchen, Wright Medical Technologies, Arlington, Tennessee) to determine if there were differences in operative time and charges, as well as early complications and early radiographic results. The unilateral intraoperative custom group had an average anesthesia time of 3 hours, 39 minutes, an operating time of 2 hours and 26 minutes, and a blood loss of 725 mL. The averages for the standard group included an anesthesia time of 2 hours, 19 minutes, a surgical time of 1 hour, 25 minutes, and a blood loss of 480 mL. By 6 months after surgery, 49 (73%) in the custom group had subsidence of 2 mm or more, compared with 10 hips (15%) in the standard group. The custom group had 17 early postoperative complications versus 3 in the standard group. The charge for the hospital stay averaged $19,950 for the custom group and $14,322 for the standard group. At the present time, the high incidence of complications and the increased charges make the intraoperative custom hip replacement an unlikely first choice of recommendation. PMID:8831891

  12. Ecohydrological Consequences of Grasses Invading Shrublands: A Comparison of Cold and Warm Deserts

    NASA Astrophysics Data System (ADS)

    Wilcox, B. P.; Turnbull, L.; Young, M.; Williams, C. J.; Ravi, S.; Seyfried, M. S.; Bowling, D. R.; Scott, R. L.; Caldwell, T. G.; Wainwright, J.; Germino, M. J.

    2010-12-01

    Exotic grasses are altering native savannas and woodlands across the globe. In this paper, we summarize the current state of knowledge concerning the ecohydrological consequences of native-shrubland-to-grassland conversion. Our objectives are to understand ecohydrological changes at the local scale, such as soil-water content or hillslope erosion; and whether these small-scale changes have consequences for larger-scale phenomena such as flooding, sedimentation in rivers, groundwater recharge, energy budgets, and weather patterns. In addition, we are interested in identifying gaps in our knowledge and research priorities. Our analysis is based on a synthesis of relevant literature complemented by simulation modeling using HYDRUS-1D and MAHLERAN. In terms of runoff and erosion, we find that the influence of grass invasion on surface runoff and erosion is different for the cold and warm deserts. For cold deserts, runoff and erosion will increase while for the warm deserts the opposite is likely to occur. In particular, erosion the erosion hazard will be greatly amplified on steep slopes (>20%) following burning. In warm deserts, grass invasion may actually reduce runoff and erosion. In terms of the vertical fluxes of evaporation and soil water recharge we find that grass invasion will likely lead to higher soil water recharge in cold deserts but not to the extent that groundwater will be affected for many, many decades and then likely not very much. In warm deserts grass invasion likely has little affect on evapotranspiration fluxes or soil water.

  13. Accounting for carbon cycle feedbacks in a comparison of the global warming effects of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Gillett, Nathan P.; Damon Matthews, H.

    2010-07-01

    Greenhouse gases other than CO2 make a significant contribution to human-induced climate change, and multi-gas mitigation strategies are cheaper to implement than those which limit CO2 emissions alone. Most practical multi-gas mitigation strategies require metrics to relate the climate warming effects of CO2 and other greenhouse gases. Global warming potential (GWP), defined as the ratio of time-integrated radiative forcing of a particular gas to that of CO2 following a unit mass emission, is the metric used in the Kyoto Protocol, and we define mean global temperature change potential (MGTP) as an equivalent metric of the temperature response. Here we show that carbon-climate feedbacks inflate the GWPs and MGTPs of methane and nitrous oxide by ~ 20% in coupled carbon-climate model simulations of the response to a pulse of 50 × 1990 emissions, due to a warming-induced release of CO2 from the land biosphere and ocean. The magnitude of this effect is expected to be dependent on the model, but it is not captured at all by the analytical models usually used to calculate metrics such as GWP. We argue that the omission of carbon cycle dynamics has led to a low bias of uncertain but potentially substantial magnitude in metrics of the global warming effect of other greenhouse gases, and we suggest that the carbon-climate feedback should be considered when greenhouse gas metrics are calculated and applied.

  14. Weather Research and Forecasting Model Sensitivity Comparisons for Warm Season Convective Initiation

    NASA Technical Reports Server (NTRS)

    Watson, Leela R.

    2007-01-01

    This report describes the work done by the Applied Meteorology Unit (AMU) in assessing the success of different model configurations in predicting warm season convection over East-Central Florida. The Weather Research and Forecasting Environmental Modeling System (WRF EMS) software allows users to choose among two dynamical cores - the Advanced Research WRF (ARW) and the Non-hydrostatic Mesoscale Model (NMM). There are also data assimilation analysis packages available for the initialization of the WRF model - the Local Analysis and Prediction System (LAPS) and the Advanced Regional Prediction System (ARPS) Data Analysis System (ADAS). Besides model core and initialization options, the WRF model can be run with one- or two-way nesting. Having a series of initialization options and WRF cores, as well as many options within each core, creates challenges for local forecasters, such as determining which configuration options are best to address specific forecast concerns. This project assessed three different model intializations available to determine which configuration best predicts warm season convective initiation in East-Central Florida. The project also examined the use of one- and two-way nesting in predicting warm season convection.

  15. Interannual Comparison of Mesospheric Responses to Stratospheric Sudden Warmings, as Seen in SABER Data, 2002-2010

    NASA Astrophysics Data System (ADS)

    Picard, R. H.; Wintersteiner, P. P.; Winick, J. R.; Mlynczak, M. G.; Russell, J.; Marshall, T.

    2010-12-01

    The past decade has seen the most active sequence of boreal winters in the satellite era. Nine of the ten years witnessed major stratospheric sudden warmings (SSWs), including three of the most intense ever observed, and there were a number of minor warmings as well. This report documents TIMED/SABER observations of mesospheric structure throughout this period, providing an interannual comparison of the extent and timing of its response to these SSWs. Mesospheric cooling is associated with all events, in variable altitude ranges, and is usually seen first at the higher altitudes. Several SSWs perturbed the OH layer, in extreme cases producing a rise in its altitude followed by a descent to abnormally low levels. The timing of both cooling and OH layer changes with respect to the SSW is consistent from event to event. The occurrence of four SSWs within a period of ~35 days in 2008 produced a quasiperiodic response in the mesosphere that illustrates the temporal relationships even more clearly than the interannual comparisons do.

  16. A Comparison of Variable Total and Ultraviolet Solar Irradiance Inputs to 20 th Century Global Warming

    NASA Astrophysics Data System (ADS)

    Foukal, P. V.

    2002-05-01

    Analysis of spaceborne radiometry has shown that the total solar irradiance variation over the past two activity cycles was approximately proportional to the weighted difference between areas of dark spots and bright faculae and enhanced network. Empirical models of ultraviolet irradiance variation indicate that its behavior is dominated by changes in area of the bright component alone, whose photometric contrast increases at shorter wavelength.This difference in time behavior of total and UV irradiances could help to discriminate between their relative importance in forcing of global warming. Our recent digitization of archival Ca K images from Mt Wilson and NSO provides the first direct measurement of variations in area of the bright component, extending between 1915 and 1999 (previous models have relied on the sunspot number or other proxies to estimate the bright - component contribution). We use these more direct measurements to derive the time behavior of solar total and UV irradiance variation, over this period .We find that they are significantly different;the total irradiance variation accounts for over 80 percent of the variance in global temperature during this period, while the ultraviolet irradiance variation accounts for only about 20 percent. The amplitude of total irradiance variation in our model is smaller than required to influence global warming,in current climate models.Also, the impact of sulfate aerosol variations on the extended cooling between the 1940's and 1970's must be better understood before the significance of correlations between 20 th century global warming, and any solar activity index can be properly assessed. Despite these caveats, the lower correlation we find between global temperature and UV,compared to total, irradiance requires consideration in the search for physical mechanisms linking solar activity and climate. This work was supported in part under NASA grant NAG5-7607 to CRI, Inc., and NAG5-10998 to the Applied Physics Laboratory, Johns Hopkins University.

  17. What is "good reasoning" about global warming? A comparison of high school students and specialists

    NASA Astrophysics Data System (ADS)

    Adams, Stephen Thomas

    This study compares the knowledge and reasoning about global warming of 10 twelfth grade students and 6 specialists, including scientists and policy analysts. The study uses global warming as a context for addressing the broad objective of formulating goals for scientific literacy. Subjects evaluated a set of articles about global warming and evaluated policies proposed to ameliorate global warming, including a gasoline tax and a "feebate" system of fees and rebates on automobiles. All students and one scientist participated in a full treatment involving interviews and activities with a computer program (discussed below), averaging about 3.75 hours. In addition, five specialists participated in interviews only, averaging one hour. One line of analysis focuses on knowledge content, examining how subjects applied perspectives from both natural and social sciences. This analysis is positioned as an empirical component to the movement to develop content standards for science education, as exemplified by the recommendations of Science for All Americans (SFAA). Some aspects of competent performance in the present study hinged upon knowledge and skills advocated by SFAA (e.g., fluency with themes of science such as scale). Other aspects involved such skills as evaluating economic interests behind a scientific argument in the media or considering hidden costs in a policy area. By characterizing a range of approaches to how students and specialists performed the experimental tasks, the present study affords a view of scientific literacy not possible without this type of information. Another line of analysis investigates a measure of coherent argumentation from a computer program, Convince Me, in relation to policy reasoning. The program is based on a connectionist model, ECHO. Subjects used the program to create arguments about the aforementioned policies. The study compares Convince Me's Model's Fit argumentation measure to other measures, including ratings of 6 human judges about the quality of the arguments, a measure of the stability of subjects' views, and the number of statements in subjects' arguments. The pattern of significant correlations among several of these measures, plus interview findings, help to clarify cognitive and educational issues involved with using Convince Me (or related programs) in this area.

  18. Do cities simulate climate change? A comparison of herbivore response to urban and global warming

    USGS Publications Warehouse

    Youngsteadt, Elsa; Dale, Adam G.; Terando, Adam J.; Dunn, Robert R.; Frank, Steven D.

    2014-01-01

    Cities experience elevated temperature, CO2, and nitrogen deposition decades ahead of the global average, such that biological response to urbanization may predict response to future climate change. This hypothesis remains untested due to a lack of complementary urban and long-term observations. Here, we examine the response of an herbivore, the scale insect Melanaspis tenebricosa, to temperature in the context of an urban heat island, a series of historical temperature fluctuations, and recent climate warming. We survey M. tenebricosa on 55 urban street trees in Raleigh, NC, 342 herbarium specimens collected in the rural southeastern United States from 1895 to 2011, and at 20 rural forest sites represented by both modern (2013) and historical samples. We relate scale insect abundance to August temperatures and find that M. tenebricosa is most common in the hottest parts of the city, on historical specimens collected during warm time periods, and in present-day rural forests compared to the same sites when they were cooler. Scale insects reached their highest densities in the city, but abundance peaked at similar temperatures in urban and historical datasets and tracked temperature on a decadal scale. Although urban habitats are highly modified, species response to a key abiotic factor, temperature, was consistent across urban and rural-forest ecosystems. Cities may be an appropriate but underused system for developing and testing hypotheses about biological effects of climate change. Future work should test the applicability of this model to other groups of organisms.

  19. Do cities simulate climate change? A comparison of herbivore response to urban and global warming.

    PubMed

    Youngsteadt, Elsa; Dale, Adam G; Terando, Adam J; Dunn, Robert R; Frank, Steven D

    2015-01-01

    Cities experience elevated temperature, CO2 , and nitrogen deposition decades ahead of the global average, such that biological response to urbanization may predict response to future climate change. This hypothesis remains untested due to a lack of complementary urban and long-term observations. Here, we examine the response of an herbivore, the scale insect Melanaspis tenebricosa, to temperature in the context of an urban heat island, a series of historical temperature fluctuations, and recent climate warming. We survey M. tenebricosa on 55 urban street trees in Raleigh, NC, 342 herbarium specimens collected in the rural southeastern United States from 1895 to 2011, and at 20 rural forest sites represented by both modern (2013) and historical samples. We relate scale insect abundance to August temperatures and find that M. tenebricosa is most common in the hottest parts of the city, on historical specimens collected during warm time periods, and in present-day rural forests compared to the same sites when they were cooler. Scale insects reached their highest densities in the city, but abundance peaked at similar temperatures in urban and historical datasets and tracked temperature on a decadal scale. Although urban habitats are highly modified, species response to a key abiotic factor, temperature, was consistent across urban and rural-forest ecosystems. Cities may be an appropriate but underused system for developing and testing hypotheses about biological effects of climate change. Future work should test the applicability of this model to other groups of organisms. PMID:25163424

  20. Intraoperative virtual brain counseling

    NASA Astrophysics Data System (ADS)

    Jiang, Zhaowei; Grosky, William I.; Zamorano, Lucia J.; Muzik, Otto; Diaz, Fernando

    1997-06-01

    Our objective is to offer online real-tim e intelligent guidance to the neurosurgeon. Different from traditional image-guidance technologies that offer intra-operative visualization of medical images or atlas images, virtual brain counseling goes one step further. It can distinguish related brain structures and provide information about them intra-operatively. Virtual brain counseling is the foundation for surgical planing optimization and on-line surgical reference. It can provide a warning system that alerts the neurosurgeon if the chosen trajectory will pass through eloquent brain areas. In order to fulfill this objective, tracking techniques are involved for intra- operativity. Most importantly, a 3D virtual brian environment, different from traditional 3D digitized atlases, is an object-oriented model of the brain that stores information about different brain structures together with their elated information. An object-oriented hierarchical hyper-voxel space (HHVS) is introduced to integrate anatomical and functional structures. Spatial queries based on position of interest, line segment of interest, and volume of interest are introduced in this paper. The virtual brain environment is integrated with existing surgical pre-planning and intra-operative tracking systems to provide information for planning optimization and on-line surgical guidance. The neurosurgeon is alerted automatically if the planned treatment affects any critical structures. Architectures such as HHVS and algorithms, such as spatial querying, normalizing, and warping are presented in the paper. A prototype has shown that the virtual brain is intuitive in its hierarchical 3D appearance. It also showed that HHVS, as the key structure for virtual brain counseling, efficiently integrates multi-scale brain structures based on their spatial relationships.This is a promising development for optimization of treatment plans and online surgical intelligent guidance.

  1. Weather Research and Forecasting Model Sensitivity Comparisons for Warm Season Convective Initiation

    NASA Technical Reports Server (NTRS)

    Watson, Leela R.; Hoeth, Brian; Blottman, Peter F.

    2007-01-01

    Mesoscale weather conditions can significantly affect the space launch and landing operations at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS). During the summer months, land-sea interactions that occur across KSC and CCAFS lead to the formation of a sea breeze, which can then spawn deep convection. These convective processes often last 60 minutes or less and pose a significant challenge to the forecasters at the National Weather Service (NWS) Spaceflight Meteorology Group (SMG). The main challenge is that a "GO" forecast for thunderstorms and precipitation at the Shuttle Landing Facility is required at the 90 minute deorbit decision for End Of Mission (EOM) and at the 30 minute Return To Launch Site (RTLS) decision. Convective initiation, timing, and mode also present a forecast challenge for the NWS in Melbourne, FL (MLB). The NWS MLB issues such tactical forecast information as Terminal Aerodrome Forecasts (TAF5), Spot Forecasts for fire weather and hazardous materials incident support, and severe/hazardous weather Watches, Warnings, and Advisories. Lastly, these forecasting challenges can also affect the 45th Weather Squadron (45 WS), which provides comprehensive weather forecasts for shuttle launch, as well as ground operations, at KSC and CCAFS. The need for accurate mesoscale model forecasts to aid in their decision making is crucial. This study specifically addresses the skill of different model configurations in forecasting warm season convective initiation. Numerous factors influence the development of convection over the Florida peninsula. These factors include sea breezes, river and lake breezes, the prevailing low-level flow, and convergent flow due to convex coastlines that enhance the sea breeze. The interaction of these processes produces the warm season convective patterns seen over the Florida peninsula. However, warm season convection remains one of the most poorly forecast meteorological parameters. To determine which configuration options are best to address this specific forecast concern, the Weather Research and Forecasting (WRF) model, which has two dynamical cores - the Advanced Research WRF (ARW) and the Non-hydrostatic Mesoscale Model (NMM) was employed. In addition to the two dynamical cores, there are also two options for a "hot-start" initialization of the WRF model - the Local Analysis and Prediction System (LAPS; McGinley 1995) and the Advanced Regional Prediction System (ARPS) Data Analysis System (ADAS; Brewster 1996). Both LAPS and ADAS are 3- dimensional weather analysis systems that integrate multiple meteorological data sources into one consistent analysis over the user's domain of interest. This allows mesoscale models to benefit from the addition of highresolution data sources. Having a series of initialization options and WRF cores, as well as many options within each core, provides SMG and MLB with considerable flexibility as well as challenges. It is the goal of this study to assess the different configurations available and to determine which configuration will best predict warm season convective initiation.

  2. Comparison of Warm Blood Cardioplegia Delivery With or Without the Use of a Roller Pump

    PubMed Central

    Faber, Mizja M.; Noordzij, Peter G.; Hennink, Simon; Kelder, Hans; de Vroege, Roel; Waanders, Frans G.; Daeter, Edgar; Stehouwer, Marco C.

    2015-01-01

    Abstract: Various techniques for administration of blood cardioplegia are used worldwide. In this study, the effect of warm blood cardioplegia administration with or without the use of a roller pump on perioperative myocardial injury was studied in patients undergoing coronary artery bypass grafting using minimal extra-corporeal circuits (MECCs). Sixty-eight patients undergoing elective coronary bypass surgery with an MECC system were consecutively enrolled and randomized into a pumpless group (PL group: blood cardioplegia administration without roller pump) or roller pump group (RP group: blood cardioplegia administration with roller pump). No statistically significant differences were found between the PL group and RP group regarding release of cardiac biomarkers. Maximum postoperative biomarker values reached at T1 (after arrival intensive care unit) for heart-type fatty acid binding protein (2.7 [1.5; 6.0] ng/mL PL group vs. 3.2 [1.6; 6.3] ng/mL RP group, p = .63) and at T3 (first postoperative day) for troponin T high-sensitive (22.0 [14.5; 29.3] ng/L PL group vs. 21.1 [15.3; 31.6] ng/L RP group, p = .91), N-terminal pro-brain natriuretic peptide (2.1 [1.7; 2.9] ng/mL PL group vs. 2.6 [1.6; 3.6] ng/mL RP group, p = .48), and C-reactive protein (138 [106; 175] μg/mL PL group vs. 129 [105; 161] μg/mL RP group, p = .65). Besides this, blood cardioplegia flow, blood cardioplegia line pressure, and aortic root pressure during blood cardioplegia administration were similar between the two groups. Administration of warm blood cardioplegia with or without the use of a roller pump results in similar clinically acceptable myocardial protection. PMID:26834282

  3. How do surgeons make intraoperative decisions?

    PubMed Central

    Flin, Rhona; Youngson, George; Yule, Steven

    2007-01-01

    Surgeons' intraoperative decision making is a key element of clinical practice, yet has received scant attention in the surgical literature. In recent years, serial changes in the configuration of surgical training in the UK have reduced the time spent by trainees in the operating theatre. The opportunity to replace this lost experience with active teaching of decision making is important, but there seem to have been very few studies that have directly examined the cognitive skills underlying surgical decision making during operations. From the available evidence in surgery, and drawing from research in other safety‐critical occupations, four decision‐making strategies that surgeons may use are discussed: intuitive (recognition‐primed), rule based, option comparison and creative. Surgeons' decision‐making processes should be studied to provide a better evidence base for the training of cognitive skills for the intraoperative environment. PMID:17545353

  4. SU-E-T-537: Comparison of Intra-Operative Soft X-Rays to Low Energy Electron Beams for Treatment of Superficial Lesions

    SciTech Connect

    Chinsky, B; Diak, A; Gros, S; Sethi

    2014-06-01

    Purpose: Superficial soft x-ray applicators have recently been designed for use with existing intra-operative radiotherapy systems. These applicators may be used in treating superficial lesions which are conventionally treated with electron beams. The purpose of this abstract is to compare dose distributions of an intra-operative 50kV x-ray unit with low energy electrons for the treatment of superficial lesions. Methods: Dosimetric parameters for 1 and 3-cm diameter Intrabeam superficial x-ray applicators were measured with EBT3 Gafchromic film in a solid water phantom. Depth dose distributions and profiles (d=2, 5, 10 and 15mm) were obtained by prescribing a dose of 400cGy at 5mm depth below the phantom surface. Corresponding dose profiles for 6-MeV electrons were acquired from a Varian Clinac 21EX at 100 SSD. H and D calibration curves were generated for each modality for 0-800cGy. Results: Dose coverage, penumbra, dose uniformity, surface dose, and dose fall-off were examined. Compared to electrons, Intrabeam lateral dose coverage at 5mm depth was 70% larger with a much sharper (1/4) penumbra. Electron isodose levels bulged with depth, whereas Intrabeam isodose levels exhibited a convex cone shape. The Intrabeam dose profiles demonstrated horns in the dose distribution up to a 5mm depth and an exponential dose fall-off. Relative surface dose was higher for the Intrabeam applicators. Treatment times were comparable for both modalities. Conclusions: The very small penumbra of Intrabeam at shallow depths could be useful in treating superficial lesions adjacent to critical structures. The exponential dose fall-off of Intrabeam makes it appealing in the sparing of structures beyond the lesion. However, for lesions past a depth of 5mm, electrons would be desirable as they penetrate farther and provide skin sparing. Intrabeam may be preferable for sites that are difficult to treat with electrons due to mechanical and physical limitations.

  5. Comparison of Oxidation and Microstructure of Warm-Sprayed and Cold-Sprayed Titanium Coatings

    NASA Astrophysics Data System (ADS)

    Kim, KeeHyun; Kuroda, Seiji; Watanabe, Makoto; Huang, RenZhong; Fukanuma, Hirotaka; Katanoda, Hiroshi

    2012-06-01

    Thick titanium coatings were prepared by the warm spraying (WS) and cold spraying (CS) processes to investigate the oxidation and microstructure of the coating layers. Prior to the coating formations, the temperature and velocity of in-flight titanium powder particles were numerically calculated. Significant oxidation occurred in the WS process using higher gas temperature conditions with low nitrogen flow rate, which is mixed to the flame jet of a high velocity oxy-fuel (HVOF) spray gun in order to control the temperature of the propellant gas. Oxidation, however, decreased strikingly as the nitrogen flow rate increased. In the CS process using nitrogen or helium as a propellant gas, little oxidation was observed. Even when scanning electron microscopy or an x-ray diffraction method did not detect oxides in the coating layers produced by WS using a high nitrogen flow rate or by CS using helium, the inert gas fusion method revealed minor increases of oxygen content from 0.01 to 0.2 wt.%. Most of the cross-sections of the coating layers prepared by conventional mechanical polishing looked dense. However, the cross-sections prepared by an ion-milling method revealed the actual microstructures containing small pores and unbounded interfaces between deposited particles.

  6. Infrared absorption spectra, radiative efficiencies, and global warming potentials of perfluorocarbons: Comparison between experiment and theory

    NASA Astrophysics Data System (ADS)

    Bravo, IvN.; Aranda, Alfonso; Hurley, Michael D.; Marston, George; Nutt, David R.; Shine, Keith P.; Smith, Kevin; Wallington, Timothy J.

    2010-12-01

    Experimentally and theoretically determined infrared spectra are reported for a series of straight-chain perfluorocarbons: C2F6, C3F8, C4F10, C5F12, C6F14, and C8F18. Theoretical spectra were determined using both density functional (DFT) and ab initio methods. Radiative efficiencies (REs) were determined using the method of Pinnock et al. (1995) and combined with atmospheric lifetimes from the literature to determine global warming potentials (GWPs). Theoretically determined absorption cross sections were within 10% of experimentally determined values. Despite being much less computationally expensive, DFT calculations were generally found to perform better than ab initio methods. There is a strong wavenumber dependence of radiative forcing in the region of the fundamental C-F vibration, and small differences in wavelength between band positions determined by theory and experiment have a significant impact on the REs. We apply an empirical correction to the theoretical spectra and then test this correction on a number of branched chain and cyclic perfluoroalkanes. We then compute absorption cross sections, REs, and GWPs for an additional set of perfluoroalkenes.

  7. Innovations in Intraoperative Tumor Visualization.

    PubMed

    Visgauss, Julia D; Eward, William C; Brigman, Brian E

    2016-01-01

    In the surgical management of solid tumors, adequacy of tumor resection has implications for local recurrence and survival. The standard method of intraoperative identification of tumor margin is frozen section pathologic analysis, which is time-consuming with potential for sampling error. Intraoperative tumor visualization has the potential to significantly improve surgical cancer care across disciplines, by guiding accuracy of biopsies, increasing adequacy of resections, directing adjuvant therapy, and even providing diagnostic information. We provide an outline of various methods of intraoperative tumor visualization developed to aid in the real-time assessment of tumor extent and adequacy of resection. PMID:26614939

  8. Comparison of metabolic and biomechanic responses to active vs. passive warm-up procedures before physical exercise.

    PubMed

    Brunner-Ziegler, Sophie; Strasser, Barbara; Haber, Paul

    2011-04-01

    Active warm-up before physical exercise is a widely accepted practice to enhance physical performance, whereas data on modalities to passively raise tissue temperature are rare. The study compared the effect of active vs. passive warm-up procedures before exercise on energy supply and muscle strength performance. Twenty young, male volunteers performed 3 spiroergometer-test series without prior warm-up and after either an active or passive warm-up procedure. Oxygen uptake (VO2), heart rate (HR), pH value, and lactate were determined at 80% of individual VO2max values and during recovery. Comparing no prior warm-up with passive warm-up, pH values were lower at the fourth test minute (p < 0.004), and lactate values were higher at the sixth and third minutes of recovery (p < 0.01 and p < 0.010, respectively), after no prior warm-up. Comparing active with passive warm-up, HR was lower, and VO2 values were higher at the fourth and sixth test minutes (p < 0.033 and p < 0.011, respectively, and p < 0.015 and p < 0.022, respectively) after active warm-up. Differentiation between active and passive warm-up was more pronounced than between either warm-up or no warm-up. Conditions that may promote improved performance were more present after active vs. passive warm-up. Thus, athletes may reach the metabolic steady state faster after active warm-up. PMID:20733525

  9. Formation and evolution of periglacial landforms in context of global warming: Comparison Earth-Mars

    NASA Astrophysics Data System (ADS)

    Séjourné, A.; Costard, F.; Gargani, J.; Marmo, C.

    2012-04-01

    Abrupt climate-changes in the periglacial environments on Earth such as Central Yakutia (Siberia) deeply modified the landscape. This region is underlined by a continuous permafrost that is ice-rich, ~40-80% of ice by volume. The permafrost was formed during the last Pleistocene glaciation. A unique assemblage of landforms is observed: ice-wedge polygons, polygon-junction ponds and thermokarst lakes. The ice-wedges polygons are formed by thermal-contraction of an ice-cemented ground due to rapid drop of air temperature <0°C. The thawing of the network of polygons underlined by ice-wedges produces ponds localized at the junction of polygons. The thermokarst lakes are the result of the subsidence of the ground following the localized thawing of excess-ice. Most of thermokarst lakes were formed during the Holocene climatic optimum where higher temperatures induced the extensive thawing of the permafrost. Now, the planet Mars is a cold and dry desert, the mean pressure is 6 mbar and mean temperature is -55°C. However, in the last few years, evidences of Mars being an ice-rich planet have become increasingly abundant. The region of Utopia Planitia in the northern mid-latitudes contains relatively young (< 10 Myr) landforms: small-sized polygons (~100 m in diam.), polygon-junction pits (~10 m in diam.) and scalloped depressions (~100-1000 m in diam.). Several authors showed that they are possibly periglacial landforms like on Earth, however their origin is still enigmatic. We conducted a geomorphologic study of all landforms in Utopia Planitia with high-resolution satellite imagery and topographical data. Then, we compared the Martian morphologies with analogous periglacial landforms of Siberia to understand their processes of formation. In Utopia Planitia, the small-sized polygons have a morphology similar to ice-wedges polygons on Earth and indicate the presence of an ice-cemented ground. The polygon-junction pits are interpreted to be due the sublimation of potential ice-wedges and subsequent subsidence of the ground producing pits. The scalloped depressions are similar in shape and size to thermokarst lakes. They are thought to be due to degradation of ground-ice by melting or sublimation of ground-ice and subsidence of the ground. Our results show that the assemblage of landforms in Utopia Planitia indicates the presence of an ice-rich permafrost like on Earth. We suggest that this permafrost were formed during cold climatic periods and then were degraded during a relatively recent global warming. Our results show that the permafrost was degraded during a high obliquity periods of Mars. But the question is how major climate-changes could occur on Mars. Mars is thought to have undergone important variations in the orbital parameters during the last 10 Myr dramatically changing the climate. Therefore, Utopia Planitia is probably a marker of one of the last major climate change that occurred on Mars.

  10. Comparison between natural Rain drop size distributions and corresponding models near equilibrium state during warm rain

    NASA Astrophysics Data System (ADS)

    Barthes, Laurent; Mallet, Cécile

    2010-05-01

    Keywords: Rain Drop Size Distribution, Breakup, coalescence, disdrometer The study of the vertical evolution of raindrop size distributions (DSDs) during rainfall, from the freezing level isotherm to ground level, is a key to improving our understanding of the microphysics of rain. In numerous domains such as remote sensing, telecommunications, soil erosion, and the study of the rain's efficiency in 'washing' the atmosphere, the DSD plays an important role. Among the different processes affecting the evolution of DSD, breakup and coalescence are two of the most significant. Models of coalescence and breakup lead to equilibrium of the raindrop size distribution (DSD) after a fall through sufficient vertical height. At equilibrium, the DSD no longer evolves, and its shape is unique whatever the rain rate or LWC. This implies that the DSD is known, to within a multiplication constant. These models based on experimental measurements have been developed over the past 40 years. The Low and List (1982a,b) parameterization (hereinafter LL82) and the Greg M. McFarquhar (2004) model are both based on the same laboratory experiments, which lead to an equilibrium drop size distribution (EDSD) with two or three peaks, and an exponential tail with a slope of approximately Λ=65 cm-1. Numerous measurements using disdrometer collected in different climatic areas: Paris, France (Mars to October 2000), Iowa-City (April to October 2002), and Djougou (Benin June to September 2006) corresponding to 537 hours of rain period have shown that for high rain rates, close to a state of equilibrium, this slope lies between Λ=20 - 22 cm-1. This latter value is corroborated by others measurements found in the literature (Hu & Srivastava, 1995). Hu & Srivastava suggested that the Low and List parameterization may overestimate the effects of the breakup process. This hypothesis is in adequation with recent laboratory experiments (A.P. Barros 2008) in which the authors conclude that the number of fragments droplets produced when small drops and large drops collide is overestimate. As new parameterization of LL82 is not possible due to the lack of new sufficient large experimental dataset, we have simply tried in the present study to 'compensate' the problem previously mentioned by replacing the coalescence/breakup model proposed in LL82 by another one in which the breakup process is less dominant. In order to evaluate the relevance of this modification, some of the DSD parameters such as slope, mean volume diameter, and relation between moments are calculated, and comparisons with experimental DSD are made. Simulations at equilibrium lead to a DSD tail with a slope of 23 cm-1 and a mean volume diameter equal to 2.5 mm. These values are in good agreements with experimental data. Similarly, the linear relationship between No* and the rainfall rate is also in good agreement. In the last part, the modified parameterization is then used to study the evolution of an initially gamma-like DSD in a 1D vertical rain shaft. References Barros, A. P., O. P. Prat, P. Shrestha, F. Y. Testik, and L. F. Bliven, 2008. Revisiting Low and List (1982): evaluation of raindrop collision using laboratory observations and modeling. Journal of the Atmospheric Sciences. Vol. 65(9), pp. 2983-2993. Hu, Z., and R. C. Srivastava: 1995: Evolution of raindrop size distribution by coalescence, breakup, and evaporation: Theory and observations. J. Atmos. Sci., 52, 1761-1783. Low, T. B. and R. List, 1982a: Collision, coalescence, and breakup of raindrops. Part I: Experimentally established coalescence efficiencies and fragment size distributions in breakup. J. Atmos. Sci., 39, 1591-1606. ___ 1982b: Collision, coalescence, and breakup of raindrops. Part II: Parameterization of fragment size distributions. J. Atmos. Sci., 39, 1607-1618. McFarquhar, G. M, 2004: A new representation of collision-induced breakup of raindrops and its implications for the shapes of raindrop size distributions, J. Atmos. Sci., 61(7), 777-794.

  11. Dosimetry for electron Intra-Operative RadioTherapy: Comparison of output factors obtained through alanine/EPR pellets, ionization chamber and Monte Carlo-GEANT4 simulations for IORT mobile dedicate accelerator

    NASA Astrophysics Data System (ADS)

    Marrale, Maurizio; Longo, Anna; Russo, Giorgio; Casarino, Carlo; Candiano, Giuliana; Gallo, Salvatore; Carlino, Antonio; Brai, Maria

    2015-09-01

    In this work a comparison between the response of alanine and Markus ionization chamber was carried out for measurements of the output factors (OF) of electron beams produced by a linear accelerator used for Intra-Operative Radiation Therapy (IORT). Output factors (OF) for conventional high-energy electron beams are normally measured using ionization chamber according to international dosimetry protocols. However, the electron beams used in IORT have characteristics of dose per pulse, energy spectrum and angular distribution quite different from beams usually used in external radiotherapy, so the direct application of international dosimetry protocols may introduce additional uncertainties in dosimetric determinations. The high dose per pulse could lead to an inaccuracy in dose measurements with ionization chamber, due to overestimation of ks recombination factor. Furthermore, the electron fields obtained with IORT-dedicated applicators have a wider energy spectrum and a wider angular distribution than the conventional fields, due to the presence of electrons scattered by the applicator's wall. For this reason, a dosimetry system should be characterized by a minimum dependence from the beam energy and from angle of incidence of electrons. This become particularly critical for small and bevelled applicators. All of these reasons lead to investigate the use of detectors different from the ionization chamber for measuring the OFs. Furthermore, the complete characterization of the radiation field could be accomplished also by the use of Monte Carlo simulations which allows to obtain detailed information on dose distributions. In this work we compare the output factors obtained by means of alanine dosimeters and Markus ionization chamber. The comparison is completed by the Monte Carlo calculations of OFs determined through the use of the Geant4 application "iort _ therapy" . The results are characterized by a good agreement of response of alanine pellets and Markus ionization chamber and Monte Carlo results (within about 3%) for both flat and bevelled applicators.

  12. Comparison of warm and cold years on the southeastern Bering Sea shelf and some implications for the ecosystem

    NASA Astrophysics Data System (ADS)

    Stabeno, Phyllis J.; Kachel, Nancy B.; Moore, Sue E.; Napp, Jeffrey M.; Sigler, Michael; Yamaguchi, Atsushi; Zerbini, Alexandre N.

    2012-06-01

    The southeastern, middle shelf of the Bering Sea has exhibited extreme variability in sea ice extent, temperature, and the distribution and abundance of species at multiple trophic levels over the past four decades. From 1972-2000, there was high interannual variability of areal extent of sea ice during spring (March-April). In 2000, this shifted to a 5-year (2001-2005) period of low ice extent during spring, which transitioned to a 4-year (2007-2010) period of extensive sea ice. High (low) areal extent of sea ice in spring was associated with cold (warm) water column temperatures for the following 6-7 months. The ocean currents also differed between warm and cold years. During cold years, the monthly-mean currents over the shelf were largely westward, while in warm years the direction of currents was more variable, with northward flow during December-February and relatively weak flow during the remainder of the year. The types and abundance of zooplankton differed sharply between warm and cold years. This was especially true during the prolonged warm period (2001-2005) and cold period (2007-2010), and was less evident during the years of high interannual variability. During the warm period, there was a lack of large copepods and euphausiids over the shelf; however, their populations rebounded during cold period. Small crustacean zooplankton taxa did not appear to vary between and warm and cold years. For both walleye pollock and Pacific cod, year-class strength (recruitment) was low during the prolonged warm period, but improved during the following cold period. Year-class strength did not appear to vary as a function of warm and cold years during the period of high year-to-year variability. Also, recruitment of arrowtooth flounder (a predator of pollock and cod) did not appear influenced by the warm or cold years. Finally, the distribution and relative abundance of fin whales appeared to differ in warm and cold years, with fewer whales on the southeastern, middle shelf during warm years.

  13. Intraoperative fracture of phacoemulsification tip.

    PubMed

    Angmo, Dewang; Khokhar, Sudarshan K; Ganguly, Anasua

    2014-01-01

    Phacoemulsification (phaco) is an established procedure for cataract extraction and has undergone a significant advances in techniques, machines and phaco tips. The Aspiration Bypass System (ABS) phaco tip was introduced for phacoemulsification in 1998. The ABS tip allows fluid to be drawn through the opening when the phaco tip is occluded by nuclear material. The ABS tip allowed the safe use of high vacuum and flow rates and improved chamber stability by decreasing surge and therefore reducing intraoperative complications. To date, no disadvantages of ABS tips have been reported. We report a unique case of an intraoperative break of an ABS phaco tip during routine cataract surgery. PMID:24669153

  14. A national dosimetry audit of intraoperative radiotherapy

    PubMed Central

    Earner, B; Faulkner, P; Dancer, N

    2013-01-01

    Objective: National dosimetry audits are a fundamental part of quality assurance in radiotherapy, especially for new techniques. Intraoperative radiotherapy with a compact mobile kilovoltage X-ray source is a novel approach for the treatment of breast and other cancers. All seven current clinical sites in the UK were audited by a single visiting group and set of measurement equipment. Methods: Measurements of output, isotropy and depth doses were performed using an ion chamber in solid water, thermoluminescent dosemeters and radiochromic film, respectively. Results: The mean difference between measured and planned dose across all centres was ?3.22.7%. Measured isotropy was within 3% around the lateral plane of the X-ray source and +114% in the forward direction compared with the lateral plane. Measured depth doses were agreed within 52% of manufacturer-provided calibration values or a mean gamma index of 97% at a tolerance of 7%/0.5?mm. Conclusion: Agreement within measurement uncertainties was found for all three parameters except forward anisotropy, which is unlikely to be clinically significant. Steep dose gradients increase the sensitivity to small variations in positioning, but these tests are practical for use in interdepartmental audits and local baseline comparison. Advances in knowledge: The first UK interdepartmental audit of intraoperative radiotherapy builds confidence in the delivery of this treatment. PMID:24133058

  15. Sea surface temperatures of the mid-Piacenzian Warm Period: A comparison of PRISM3 and HadCM3

    USGS Publications Warehouse

    Dowsett, H.J.; Haywood, A.M.; Valdes, P.J.; Robinson, M.M.; Lunt, D.J.; Hill, D.J.; Stoll, D.K.; Foley, K.M.

    2011-01-01

    It is essential to document how well the current generation of climate models performs in simulating past climates to have confidence in their ability to project future conditions. We present the first global, in-depth comparison of Pliocene sea surface temperature (SST) estimates from a coupled ocean-atmosphere climate model experiment and a SST reconstruction based on proxy data. This enables the identification of areas in which both the climate model and the proxy dataset require improvement. In general, the fit between model-produced SST anomalies and those formed from the available data is very good. We focus our discussion on three regions where the data-model anomaly exceeds 2 ??C 1) In the high latitude North Pacific, a systematic model error may result in anomalies that are too cold. Also, the deeper Pliocene thermocline may cause disagreement along the California margin; either the upwelling in the model is too strong or the modeled thermocline is not deep enough. 2) In the North Atlantic, the model predicts cooling in the center of a data-based warming trend that steadily increases with latitude from +. 1.5 ??C to >+ 6 ??C. The discrepancy may arise because the modeled North Atlantic Current is too zonal compared to reality, which is reinforced by the lowering of the altitude of the Pliocene Western Cordillera Mountains. In addition, the model's use of modern bathymetry in the higher latitudes may have led the model to underestimate the northward penetration of warmer surface water into the Arctic. 3) Finally, though the data and model show good general agreement across most of the Southern Ocean, a few locations show offsets due to the modern land-sea mask used in the model. Additional considerations could account for many of the modest data-model anomalies, such as differences between calibration climatologies, the oversimplification of the seasonal cycle, and differences between SST proxies (i.e. seasonality and water depth). New SST estimates from data-sparse and regionally important areas will greatly enhance our ability to judge model performance. ?? 2011.

  16. Intraoperative transfusion practices in Europe

    PubMed Central

    Meier, J.; Filipescu, D.; Kozek-Langenecker, S.; Llau Pitarch, J.; Mallett, S.; Martus, P.; Matot, I.

    2016-01-01

    Background. Transfusion of allogeneic blood influences outcome after surgery. Despite widespread availability of transfusion guidelines, transfusion practices might vary among physicians, departments, hospitals and countries. Our aim was to determine the amount of packed red blood cells (pRBC) and blood products transfused intraoperatively, and to describe factors determining transfusion throughout Europe. Methods. We did a prospective observational cohort study enrolling 5803 patients in 126 European centres that received at least one pRBC unit intraoperatively, during a continuous three month period in 2013. Results. The overall intraoperative transfusion rate was 1.8%; 59% of transfusions were at least partially initiated as a result of a physiological transfusion trigger- mostly because of hypotension (55.4%) and/or tachycardia (30.7%). Haemoglobin (Hb)- based transfusion trigger alone initiated only 8.5% of transfusions. The Hb concentration [mean (sd)] just before transfusion was 8.1 (1.7) g dl−1 and increased to 9.8 (1.8) g dl−1 after transfusion. The mean number of intraoperatively transfused pRBC units was 2.5 (2.7) units (median 2). Conclusion. Although European Society of Anaesthesiology transfusion guidelines are moderately implemented in Europe with respect to Hb threshold for transfusion (7–9 g dl−1), there is still an urgent need for further educational efforts that focus on the number of pRBC units to be transfused at this threshold. Clinical trial registration. NCT 01604083. PMID:26787795

  17. Global Warming.

    ERIC Educational Resources Information Center

    Hileman, Bette

    1989-01-01

    States the foundations of the theory of global warming. Describes methodologies used to measure the changes in the atmosphere. Discusses steps currently being taken in the United States and the world to slow the warming trend. Recognizes many sources for the warming and the possible effects on the earth. (MVL)

  18. Comparison of two fluid warming devices for maintaining body core temperature during living donor liver transplantation: Level 1 H-1000 vs. Fluid Management System 2000

    PubMed Central

    Han, Sangbin; Choi, Junghee; Ko, Justin Sangwook; Gwak, Misook; Lee, Suk-Koo

    2014-01-01

    Background Rapid fluid warming has been a cardinal measure to maintain normothermia during fluid resuscitation of hypovolemic patients. A previous laboratory simulation study with different fluid infusion rates showed that a fluid warmer using magnetic induction is superior to a warmer using countercurrent heat exchange. We tested whether the simulation-based result is translated into the clinical liver transplantation. Methods Two hundred twenty recipients who underwent living donor liver transplantation between April 2009 and October 2011 were initially screened. Seventeen recipients given a magnetic induction warmer (FMS2000) were matched 1 : 1 with those given a countercurrent heat exchange warmer (Level-1 H-1000) based on propensity score. Matched variables included age, gender, body mass index, model for end-stage liver disease score, graft size and time under anesthesia. Core temperatures were taken at predetermined time points. Results Level-1 and FMS groups had comparable core temperature throughout the surgery from skin incision, the beginning/end of the anhepatic phase to skin closure. (P = 0.165, repeated measures ANOVA). The degree of core temperature changes within the dissection, anhepatic and postreperfusion phase were also comparable between the two groups. The minimum intraoperative core temperature was also comparable (Level 1, 35.6℃ vs. FMS, 35.4℃, P = 0.122). Conclusions A countercurrent heat exchange warmer and magnetic induction warmer displayed comparable function regarding the maintenance of core temperature and prevention of hypothermia during living donor liver transplantation. The applicability of the two devices in liver transplantation needs to be evaluated in various populations and clinical settings. PMID:25368785

  19. Comparison of net global warming potential and greenhouse gas intensity affected by management practices in two dryland cropping sites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little is known about the effect of management practices on net global warming potential (GWP) and greenhouse gas intensity (GHGI) that account for all sources and sinks of greenhouse gas (GHG) emissions in dryland cropping systems. The objective of this study was to compare the effect of a combinat...

  20. Comparison of mesozooplankton communities from a pair of warm- and cold-core eddies off the coast of Western Australia

    NASA Astrophysics Data System (ADS)

    Strzelecki, J.; Koslow, J. A.; Waite, A.

    2007-04-01

    We examined the abundance and biomass, size, trophic and community structure of the mesozooplankton within a pair of warm- and cold-core eddies off the west coast of Australia in October 2003, about five months after their initial formation. Zooplankton assemblages were highly diverse in both eddies, with little dominance by any taxa. Assemblages were significantly different in the two eddies, and night assemblages differed from day. Contrary to initial expectation, mesozooplankton abundance and biomass were twice as high in the warm-core eddy as in the cold-core eddy. This was consistent with the higher phytoplankton and microzooplankton biomass and higher primary production in the warm-core eddy. The source water for the warm-core eddy was Leeuwin Current water with about a 10% admixture of shelf water. The plankton biomass and productivity of these water masses are substantially higher than of subtropical Indian Ocean water, the source water for the mixed layer of the cold-core eddy. Five months after eddy formation, the abundance and biomass of zooplankton in the eddies continued to reflect the values generally observed in their parent water masses. The trophic structure of the zooplankton in both eddies was dominated by carnivores (mostly chaetognaths). Although this apparent trophic structure may be an artefact of sampling oligotrophic waters with coarse-meshed (335 μm) nets, it points to a 'lumpiness' in the Sheldon particle spectrum.

  1. Comparison of "warm and wet" and "cold and icy" scenarios for early Mars in a 3-D climate model

    NASA Astrophysics Data System (ADS)

    Wordsworth, Robin D.; Kerber, Laura; Pierrehumbert, Raymond T.; Forget, Francois; Head, James W.

    2015-06-01

    We use a 3-D general circulation model to compare the primitive Martian hydrological cycle in "warm and wet" and "cold and icy" scenarios. In the warm and wet scenario, an anomalously high solar flux or intense greenhouse warming artificially added to the climate model are required to maintain warm conditions and an ice-free northern ocean. Precipitation shows strong surface variations, with high rates around Hellas basin and west of Tharsis but low rates around Margaritifer Sinus (where the observed valley network drainage density is nonetheless high). In the cold and icy scenario, snow migration is a function of both obliquity and surface pressure, and limited episodic melting is possible through combinations of seasonal, volcanic, and impact forcing. At surface pressures above those required to avoid atmospheric collapse (˜0.5 bar) and moderate to high obliquity, snow is transported to the equatorial highland regions where the concentration of valley networks is highest. Snow accumulation in the Aeolis quadrangle is high, indicating an ice-free northern ocean is not required to supply water to Gale crater. At lower surface pressures and obliquities, both H2O and CO2 are trapped as ice at the poles and the equatorial regions become extremely dry. The valley network distribution is positively correlated with snow accumulation produced by the cold and icy simulation at 41.8° obliquity but uncorrelated with precipitation produced by the warm and wet simulation. Because our simulations make specific predictions for precipitation patterns under different climate scenarios, they motivate future targeted geological studies.

  2. Intraoperative laparoscopic complications for urological cancer procedures

    PubMed Central

    Montes, Sergio Fernández-Pello; Rodríguez, Ivan Gonzalez; Ugarteburu, Rodrigo Gil; Villamil, Luis Rodríguez; Mendez, Begoña Diaz; Gil, Patricio Suarez; Madera, Javier Mosquera

    2015-01-01

    AIM: To structure the rate of intraoperative complications that requires an intraoperative or perioperative resolution. METHODS: We perform a literature review of Medline database. The research was focused on intraoperative laparoscopic procedures inside the field of urological oncology. General rate of perioperative complications in laparoscopic urologic surgery is described to be around 12.4%. Most of the manuscripts published do not make differences between pure intraoperative, intraoperative with postoperative consequences and postoperative complications. RESULTS: We expose a narrative statement of complications, possible solutions and possible preventions for most frequent retroperitoneal and pelvic laparoscopic surgery. We expose the results with the following order: retroperitoneal laparoscopic surgery (radical nephrectomy, partial nephrectomy, nephroureterectomy and adrenalectomy) and pelvic laparoscopic surgery (radical prostatectomy and radical cystectomy). CONCLUSION: Intraoperative complications vary from different series. More scheduled reports should be done in order to better understand the real rates of complications. PMID:25984519

  3. Genome Dissection of Traits Related to Domestication in Azuki Bean (Vigna angularis) and Comparison with other Warm-season Legumes

    PubMed Central

    Isemura, Takehisa; Kaga, Akito; Konishi, Saeko; Ando, Tsuyu; Tomooka, Norihiko; Han, Ouk Kyu; Vaughan, Duncan A.

    2007-01-01

    Background The objective of this study was to dissect into quantitative trait loci (QTLs) the large morphological and physiological differences between cultivated azuki bean (Vigna angularis) and a wild relative and to infer the commonalities of the QTLs for domestication-related traits across the Asian Vigna and with other warm-season legumes. Methods Two linkage maps, for the BC1F1 and F2 populations, respectively, from the same cross between azuki bean and V. nepalensis were developed. Using these linkage maps QTLs for 33 domestication-related traits were analysed and mapped. The location of mapped QTLs was compared with locations of similar QTLs in other warm-season legumes. Key Results QTLs were detected for seed-, pod-, stem- and leaf-related traits. Most traits were controlled by between two and nine QTLs but several traits, such as pod dehiscence, were controlled by single genes. QTLs for domestication-related traits were restricted to particular regions of the azuki bean genome, especially linkage groups 1, 2, 4, 7 and 9. Linkage groups 1 and 2 had QTLs for a suite of traits including pod size, germination, seed size and lower stem length. QTLs on linkage groups 7 and 9 were associated with upper stem length, maximum leaf size and pod and seed size. Pleiotropy or close linkage of genes for domestication-related traits is suggested in these regions. While some QTLs are common to azuki bean and other warm-season legumes, many are recorded for the first time in azuki bean. Conclusions QTLs for a large number of domestication-related traits have been mapped for the first time in azuki bean. QTLs with unexpected effect and new QTLs for traits such as seed size have been found. The results provide a foundation that will be useful for improvement of azuki bean and related legumes. PMID:17728336

  4. Minimalism through intraoperative functional mapping.

    PubMed

    Berger, M S

    1996-01-01

    Intraoperative stimulation mapping may be used to avoid unnecessary risk to functional regions subserving language and sensori-motor pathways. Based on the data presented here, language localization is variable in the entire population, with only certainty existing for the inferior frontal region responsible for motor speech. Anatomical landmarks such as the anterior temporal tip for temporal lobe language sites and the posterior aspect of the lateral sphenoid wing for the frontal lobe language zones are unreliable in avoiding postoperative aphasias. Thus, individual mapping to identify essential language sites has the greatest likelihood of avoiding permanent deficits in naming, reading, and motor speech. In a similar approach, motor and sensory pathways from the cortex and underlying white matter may be reliably stimulated and mapped in both awake and asleep patients. Although these techniques require an additional operative time and equipment nominally priced, the result is often gratifying, as postoperative morbidity has been greatly reduced in the process of incorporating these surgical strategies. The patients quality of life is improved in terms of seizure control, with or without antiepileptic drugs. This avoids having to perform a second costly operative procedure, which is routinely done when extraoperative stimulation and recording is done via subdural grids. In addition, an aggressive tumor resection at the initial operation lengthens the time to tumor recurrence and often obviates the need for a subsequent reoperation. Thus, intraoperative functional mapping may be best alluded to as a surgical technique that results in "minimalism in the long term". PMID:9247814

  5. Intraoperative cholangiography and bile duct injury.

    PubMed

    Sarli, L; Costi, R; Roncoroni, L

    2006-01-01

    We are not in agreement with the opinion that the credit for excellent results after laparoscopic cholecystectomy is to be attributed to the routine performing of intraoperative cholangiography. We performed 2538 laparoscopic cholecystectomies without routine intraoperative cholangiography and we obtained very low rate and severity of common bile duct injuries: there was a total of four common bile duct injuries (0.16%), in no case was the injury a major transaction, and injuries were detected intraoperatively and easily repaired with a T-tube. Cholangiography could prevent bile duct transaction, but that it is not necessary for intraoperative cholangiography to be routinely performed for this purpose. It is sufficient for intraoperative cholangiography to be performed whenever the surgeon is in doubt as to the biliary anatomy or common bile duct clearance, and that when dissection of the cholecystic peduncle proves difficult he does not hesitate to convert to open access. PMID:16333543

  6. Comparison of different cooling regimes within a shortened liquid cooling/warming garment on physiological and psychological comfort during exercise

    NASA Technical Reports Server (NTRS)

    Leon, Gloria R.; Koscheyev, Victor S.; Coca, Aitor; List, Nathan

    2004-01-01

    The aim of this study was to compare the effectiveness of different cooling regime intensities to maintain physiological and subjective comfort during physical exertion levels comparable to that engaged in during extravehicular activities (EVA) in space. We studied eight subjects (six males, two females) donned in our newly developed physiologically based shortened liquid cooling/warming garment (SLCWG). Rigorous (condition 1) and mild (condition 2) water temperature cooling regimes were compared at physical exertion levels comparable to that performed during EVA to ascertain the effectiveness of a lesser intensity of cooling in maintaining thermal comfort, thus reducing energy consumption in the portable life support system. Exercise intensity was varied across stages of the session. Finger temperature, rectal temperature, and subjective perception of overall body and hand comfort were assessed. Finger temperature was significantly higher in the rigorous cooling condition and showed a consistent increase across exercise stages, likely due to the restriction of heat extraction because of the intensive cold. In the mild cooling condition, finger temperature exhibited an overall decline with cooling, indicating greater heat extraction from the body. Rectal temperature was not significantly different between conditions, and showed a steady increase over exercise stages in both rigorous and mild cooling conditions. Ratings of overall comfort were 30% higher (more positive) and more stable in mild cooling (p<0.001). The mild cooling regime was more effective than rigorous cooling in allowing the process of heat exchange to occur, thus maintaining thermal homeostasis and subjective comfort during physical exertion.

  7. Intraoperative OCT in Surgical Oncology

    NASA Astrophysics Data System (ADS)

    South, Fredrick A.; Marjanovic, Marina; Boppart, Stephen A.

    The global incidence of cancer is rising, putting an increasingly heavy burden upon health care. The need to effectively detect and treat cancer is one of the most significant problems faced in health care today. Effective cancer treatment typically depends upon early detection and, for most solid tumors, successful removal of the cancerous tumor tissue via surgical procedures. Difficulties arise when attempting to differentiate between normal and tumor tissue during surgery. Unaided visual examination of the tissue provides only superficial, low-resolution information and often with little visual contrast. Many imaging modalities widely used for cancer screening and diagnostics are of limited use in the operating room due to low spatial resolution. OCT provides cellular resolution allowing for more precise localization of the tumor tissue. It is also relatively inexpensive and highly portable, making it well suited for intraoperative applications.

  8. Intraoperative biomarkers in renal transplantation.

    PubMed

    Lohkamp, Laura-Nanna; Öllinger, Robert; Chatzigeorgiou, Antonios; Illigens, Ben Min-Woo; Siepmann, Timo

    2016-03-01

    The emerging need for biomarkers in the management of renal transplantation is highlighted by the severity of related complications such as acute renal failure and ischaemia/reperfusion injury (IRI) and by the increasing efforts to identify novel markers of these events to predict and monitor delayed graft function (DGF) and long-term outcome. In clinical studies candidate markers such as kidney injury molecule-1, neutrophil gelatinase-associated lipocalin and interleukin-18 have been demonstrated to be valid biomarkers with high predictive value for DFG in a post-transplant setting. However, studies investigating biomarkers for early diagnosis of IRI and assumable DGF as well as identification of potential graft recipients at increased risk at the time point of transplantation lack further confirmation and translation into clinical practice. This review summarizes the current literature on the value of IRI biomarkers in outcome prediction following renal transplantation as well their capacity as surrogate end points from an intraoperative perspective. PMID:26132511

  9. INTRAOPERATIVE USE OF HANDHELD SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY IMAGING IN MACULAR SURGERY

    PubMed Central

    DAYANI, POUYA N.; MALDONADO, RAMIRO; FARSIU, SINA; TOTH, CYNTHIA A.

    2012-01-01

    Purpose To describe the intraoperative use of handheld spectral domain optical coherence tomography (SDOCT) imaging in macular surgery. Design Prospective, observational case series. Methods A handheld SDOCT device was used to obtain preincision optical coherence tomography imaging in patients undergoing vitrectomy for macular diseases. After removal of the internal limiting membrane or the epiretinal membrane, repeat intraoperative imaging was obtained. Spectral domain optical coherence tomography findings were characterized. Results An efficient technique was established for obtaining intraoperative SDOCT imaging. A total of eight patients were included in the study. Four patients underwent surgery for macular hole, three patients for epiretinal membrane, and one for vitreomacular traction. Comparison of the preincision and intraoperative SDOCT images demonstrated distinct changes in retinal contour and macular hole configuration. Intraoperative SDOCT imaging identified additional membranes in two patients. Conclusion The intraoperative use of handheld SDOCT imaging provides an efficient method for visualizing macular pathology. This technology may, in certain cases, help confirm or identify diseases that may be difficult to visualize during surgery. PMID:19823107

  10. Intraoperative radiotherapy for breast cancer

    PubMed Central

    Williams, Norman R.; Pigott, Katharine H.; Brew-Graves, Chris

    2014-01-01

    Intra-operative radiotherapy (IORT) as a treatment for breast cancer is a relatively new technique that is designed to be a replacement for whole breast external beam radiotherapy (EBRT) in selected women suitable for breast-conserving therapy. This article reviews twelve reasons for the use of the technique, with a particular emphasis on targeted intra-operative radiotherapy (TARGIT) which uses X-rays generated from a portable device within the operating theatre immediately after the breast tumour (and surrounding margin of healthy tissue) has been removed. The delivery of a single fraction of radiotherapy directly to the tumour bed at the time of surgery, with the capability of adding EBRT at a later date if required (risk-adaptive technique) is discussed in light of recent results from a large multinational randomised controlled trial comparing TARGIT with EBRT. The technique avoids irradiation of normal tissues such as skin, heart, lungs, ribs and spine, and has been shown to improve cosmetic outcome when compared with EBRT. Beneficial aspects to both institutional and societal economics are discussed, together with evidence demonstrating excellent patient satisfaction and quality of life. There is a discussion of the published evidence regarding the use of IORT twice in the same breast (for new primary cancers) and in patients who would never be considered for EBRT because of their special circumstances (such as the frail, the elderly, or those with collagen vascular disease). Finally, there is a discussion of the role of the TARGIT Academy in developing and sustaining high standards in the use of the technique. PMID:25083504

  11. A novel optical approach to intraoperative detection of parathyroid glands

    PubMed Central

    McWade, Melanie A.; Paras, Constantine; White, Lisa M.; Phay, John E.; Mahadevan-Jansen, Anita; Broome, James T.

    2014-01-01

    Background Inadvertent removal of parathyroid glands is a challenge in endocrine operations. There is a critical need for a diagnostic tool that provides sensitive, real-time parathyroid detection during procedures. We have developed an intraoperative technique using near-infrared (NIR) fluorescence for in vivo, real-time detection of the parathyroid regardless of its pathologic state. Methods NIR fluorescence was measured intraoperatively from 45 patients undergoing parathyroidectomy and thyroidectomy. Spectra were measured from the parathyroid and surrounding neck tissues during the operation with the use of a portable, probe-based fluorescence system at 785-nm excitation. Accuracy was evaluated by comparison with histology or visual recognition by the surgeon. Results NIR fluorescence detected the parathyroid in 100% of patients. Parathyroid fluorescence was stronger (1.2–18 times) than that of the thyroid with peak fluorescence at 822 nm. Surrounding tissues showed no auto-fluorescence. Disease state did not affect the ability to discriminate parathyroid glands but may account for signal variability. Conclusions NIR fluorescence spectroscopy can detect intraoperatively the parathyroid regardless of tissue pathology. The signal may be caused by calcium-sensing receptors present in the parathyroid. The signal strength and consistency indicates the simplicity and effectiveness of this method. Its implementation may limit operative time, decrease costs, and improve operative success rates. PMID:24238054

  12. Cold and Dry vs. Warm and Wet: 3D Modelling of the Late Noachian Climate and Comparison with the Geological Evidence

    NASA Astrophysics Data System (ADS)

    Wordsworth, R.; Pierrehumbert, R.; Kerber, L.; Forget, F.; Head, J.

    2014-07-01

    We present 3D climate simulations of Mars during the late Noachian / early Hesperian period. Rain and snow deposition patterns in episodically warm and warm, wet scenarios are compared with the observed spatial distribution of valley networks.

  13. Comparison of prolonged warm and cold ischemia on the solitary kidney during partial nephrectomy in a rabbit model.

    PubMed

    Tyritzis, S I; Kyroudi, A; Liatsikos, E; Manousakas, T; Karayannacos, P; Kostomitsopoulos, N; Zervas, A; Pavlakis, K; Stolzenburg, J-U; Constantinides, C

    2007-12-01

    The aim of this study was to investigate the patterns of renal function recovery during partial nephrectomy (PN) on an experimental solitary kidney rabbit model and establish the upper tolerable time limits of applied ischemia. Forty-eight New Zealand rabbits underwent an open right nephrectomy and after 30 days, the animals were clustered into five groups (A, B, C, D, E). The first four groups received an open left PN, under different types of ischemia. Groups A (n = 8) and B (n = 10) were subjected to 90 and 60 min of warm ischemia (WI), respectively, while groups C (n = 10) and D (n = 10) received 90 and 120 min of cold ischemia (CI) with ice-slush cooling. Group E (n = 10) served as sham group. Serum determinations of creatinine (SCr) and BUN were recorded preoperatively and on postoperative days (POD) 1, 3, 6 and 15. The animals were euthanized and the remaining kidneys were harvested and evaluated microscopically. The type and duration of ischemia were statistically significant parameters (P < 0.001). Groups B, C and D exhibited a similar pattern of recovery from trial initiation to the 15th POD (P = 0.788 and P = 0.068, respectively). Group A was extremely differentiated, with 100% mortality caused by uremia. The microscopic findings were consistent to the serum biochemistry. In our solitary kidney rabbit model, the upper limits of tolerable WI seem to be set on 60 min. CI can safely preserve the model's renal function--even up to 120 min. PMID:17899112

  14. Comparison greenhouse gas (GHG) emissions and global warming potential (GWP) effect of energy use in different wheat agroecosystems in Iran.

    PubMed

    Yousefi, Mohammad; Mahdavi Damghani, Abdolmajid; Khoramivafa, Mahmud

    2016-04-01

    The aims of this study were to determine energy requirement and global warming potential (GWP) in low and high input wheat production systems in western of Iran. For this purpose, data were collected from 120 wheat farms applying questionnaires via face-to-face interviews. Results showed that total energy input and output were 60,000 and 180,000 MJ ha(-1) in high input systems and 14,000 and 56,000 MJ ha(-1) in low input wheat production systems, respectively. The highest share of total input energy in high input systems recorded for electricity power, N fertilizer, and diesel fuel with 36, 18, and 13 %, respectively, while the highest share of input energy in low input systems observed for N fertilizer, diesel fuel, and seed with 32, 31, and 27 %. Energy use efficiency in high input systems (3.03) was lower than of low input systems (3.94). Total CO2, N2O, and CH4 emissions in high input systems were 1981.25, 31.18, and 1.87 kg ha(-1), respectively. These amounts were 699.88, 0.02, and 0.96 kg ha(-1) in low input systems. In high input wheat production systems, total GWP was 11686.63 kg CO2eq ha(-1) wheat. This amount was 725.89 kg CO2eq ha(-1) in low input systems. The results show that 1 ha of high input system will produce greenhouse effect 17 times of low input systems. So, high input production systems need to have an efficient and sustainable management for reducing environmental crises such as change climate. PMID:26690584

  15. Global Warming?

    ERIC Educational Resources Information Center

    Eichman, Julia Christensen; Brown, Jeff A.

    1994-01-01

    Presents information and data on an experiment designed to test whether different atmosphere compositions are affected by light and temperature during both cooling and heating. Although flawed, the experiment should help students appreciate the difficulties that researchers face when trying to find evidence of global warming. (PR)

  16. Comparison of Obturation Quality in Modified Continuous Wave Compaction, Continuous Wave Compaction, Lateral Compaction and Warm Vertical Compaction Techniques

    PubMed Central

    Aminsobhani, Mohsen; Ghorbanzadeh, Abdollah; Sharifian, Mohammad Reza; Namjou, Sara; Kharazifard, Mohamad Javad

    2015-01-01

    Objectives: The aim of this study was to introduce modified continuous wave compaction (MCWC) technique and compare its obturation quality with that of lateral compaction (LC), warm vertical compaction (WVC) and continuous wave compaction techniques (CWC). The obturation time was also compared among the four techniques. Materials and Methods: Sixty-four single-rooted teeth with 0–5° root canal curve and 64 artificially created root canals with 15° curves in acrylic blocks were evaluated. The teeth and acrylic specimens were each divided into four subgroups of 16 for testing the obturation quality of four techniques namely LC, WVC, CWC and MCWC. Canals were prepared using the Mtwo rotary system and filled with respect to their group allocation. Obturation time was recorded. On digital radiographs, the ratio of area of voids to the total area of filled canals was calculated using the Image J software. Adaptation of the filling materials to the canal walls was assessed at three cross-sections under a stereomicroscope (X30). Data were statistically analyzed using ANOVA, Tukey’s post hoc HSD test, the Kruskal Wallis test and t-test. Results: No significant difference existed in adaptation of filling materials to canal walls among the four subgroups in teeth samples (P ≥ 0.139); but, in artificially created canals in acrylic blocks, the frequency of areas not adapted to the canal walls was significantly higher in LC technique compared to MCWC (P ≤ 0.02). The void areas were significantly more in the LC technique than in other techniques in teeth (P < 0.001). The longest obturation time belonged to WVC technique followed by LC, CW and MCWC techniques (P<0.05). The difference between the artificially created canals in blocks and teeth regarding the obturation time was not significant (P = 0.41). Conclusion: Within the limitations of this in vitro study, MCWC technique resulted in better adaptation of gutta-percha to canal walls than LC at all cross-sections with fewer voids and faster obturation time compared to other techniques. PMID:26056519

  17. Value of Intraoperative Sonography in Pancreatic Surgery.

    PubMed

    Weinstein, Stefanie; Morgan, Tara; Poder, Liina; Shin, Lewis; Jeffrey, R Brooke; Aslam, Rizwan; Yee, Judy

    2015-07-01

    The utility of intraoperative sonography for pancreatic disease has been well described for detection and evaluation of neoplastic and inflammatory pancreatic disease. Intraoperative sonography can help substantially reduce surgical time as well as decrease potential injury to tissues and major structures. Imaging with sonography literally at the point of care--the surgeon's scalpel--can precisely define the location of pancreatic lesions and their direct relationship with surrounding structures in real time during surgery. This article highlights our experience with intraoperative sonography at multiple institutional sites for both open and laparoscopic surgical procedures. We use intraoperative sonography for a wide range of pancreatic disease to provide accurate localization and staging of disease, provide guidance for enucleation of nonpalpable, nonvisible tumors, and in planning the most direct and least invasive surgical approach, avoiding injury to the pancreatic duct or other vital structures. PMID:26112636

  18. Anesthesia for intraoperative radiation therapy in children

    SciTech Connect

    Friesen, R.H.; Morrison, J.E. Jr.; Verbrugge, J.J.; Daniel, W.E.; Aarestad, N.O.; Burrington, J.D.

    1987-06-01

    Intraoperative radiation therapy (IORT) is a relatively new mode of cancer treatment which is being used with increasing frequency. IORT presents several challenges to the anesthesiologist, including patients who are debilitated from their disease or chemotherapy, operations involving major tumor resections, intraoperative interdepartmental transport of patients, and remote monitoring of patients during electron beam therapy. This report discusses the anesthetic management of ten children undergoing IORT. With adequate preparation and interdepartmental communication, complications can be avoided during these challenging cases.

  19. Virtual intraoperative surgical photoacoustic microscopy

    NASA Astrophysics Data System (ADS)

    Lee, Changho; Lee, Donghyun; Zhou, Qifa; Kim, Jeehyun; Kim, Chulhong

    2015-07-01

    A virtual intraoperative surgical photoacoustic microscopy at 1064 nm wavelength (VISPAM) system was designed and fabricated by integrating a commercial type surgical microscope and laser scanning photoacoustic microscopy (PAM) with a 1064 nm pulsed laser. Based on simple augmented reality device, VISPAM could simultaneously provide 2D depth-resolved photoacoustic and magnified microscope images of surgery regions on the same vision of surgeon via an eyepiece of the microscope. The invisible 1064 nm laser removed the interruption of surgical sight due to visible laser scanning of previous report, and decreased the danger of tissue damage caused by over irradiated laser. In addition, to approach the real practical surgery application, a needle-type transducer was utilized without a water bath for PA signal coupling. In order to verify our system's performance, we conducted needle guiding as ex vivo phantom study and needle guiding and injection of carbon particles mixtures into a melanoma tumor region as in vivo study. We expect that VISPAM can be essential tool of brain and ophthalmic microsurgery.

  20. Intraoperative complications during oral implantology.

    PubMed

    Lamas Pelayo, Joana; Peñarrocha Diago, Miguel; Martí Bowen, Eva; Peñarrocha Diago, Maria

    2008-04-01

    Dental implant placement is a controlled, programmed surgical procedure, not without its complications. The aim of the present paper is to study the intraoperative complications in implant surgery, carrying out a review of articles appearing in Medline over the last 10 years. Among the intra operative complications related with surgery, hemorrhagic accidents occur most frequently in the interforaminal region, since the majority of the vascular branches enter the mandibular bone in this region. Nerve damage can arise as a consequence of inferior alveolar nerve transposition or lateralization; or the excessive intrusion of drills or implant fixture into the mandibular canal. Mandibular fractures secondary to implant placement occur more easily when placing implants in atrophic mandible. Occasionally, incorrect positioning or lack of relative parallelism in the placing of the implants causes damage to an adjacent tooth. Absence of primary stability may occur as a result of overworking the implant bed during preparation, also to poor bone quality, and more frequently to immediate post-extraction implantation. Another possible complication is the migration of implants into the maxillary sinus. PMID:18379448

  1. Intraoperative radiation therapy following pancreaticoduodenectomy.

    PubMed Central

    Evans, D B; Termuhlen, P M; Byrd, D R; Ames, F C; Ochran, T G; Rich, T A

    1993-01-01

    OBJECTIVE: To determine the morbidity and mortality of pancreaticoduodenectomy followed by electron-beam intraoperative radiation therapy (EB-IORT). SUMMARY BACKGROUND DATA: Local recurrence following pancreaticoduodenectomy occurs in 50% to 90% of patients who undergo a potentially curative surgical resection for adenocarcinoma of the pancreatic head. To improve local disease control, a more aggressive retroperitoneal dissection has been combined with adjuvant EB-IORT. METHODS: Forty-one patients with malignant neoplasms of the periampullary region underwent pancreaticoduodenectomy followed by EB-IORT between January 1989 and May 1992. EB-IORT was delivered in a dedicated operative suite, eliminating the need for patient relocation. Electron-beam energies of 6 to 12 MeV were used to deliver 10 to 20 Gy to the treatment field following resection but before pancreatic, biliary, and gastrointestinal reconstruction. RESULTS: Median operative time was 9 hours, blood loss was 1 L, perioperative transfusion requirement was 2 units, and hospital stay was 20 days. One patient died of a postoperative myocardial infarction, and four patients required reoperation, one for an anastomotic leak. No patient failed to receive EB-IORT because of operative complications during the time period of this study. CONCLUSION: Adjuvant EB-IORT after pancreaticoduodenectomy can be delivered safely, with low mortality and acceptable morbidity. Images Figure 1. Figure 1. PMID:8101073

  2. Global warming

    NASA Astrophysics Data System (ADS)

    Houghton, John

    2005-06-01

    'Global warming' is a phrase that refers to the effect on the climate of human activities, in particular the burning of fossil fuels (coal, oil and gas) and large-scale deforestation, which cause emissions to the atmosphere of large amounts of 'greenhouse gases', of which the most important is carbon dioxide. Such gases absorb infrared radiation emitted by the Earth's surface and act as blankets over the surface keeping it warmer than it would otherwise be. Associated with this warming are changes of climate. The basic science of the 'greenhouse effect' that leads to the warming is well understood. More detailed understanding relies on numerical models of the climate that integrate the basic dynamical and physical equations describing the complete climate system. Many of the likely characteristics of the resulting changes in climate (such as more frequent heat waves, increases in rainfall, increase in frequency and intensity of many extreme climate events) can be identified. Substantial uncertainties remain in knowledge of some of the feedbacks within the climate system (that affect the overall magnitude of change) and in much of the detail of likely regional change. Because of its negative impacts on human communities (including for instance substantial sea-level rise) and on ecosystems, global warming is the most important environmental problem the world faces. Adaptation to the inevitable impacts and mitigation to reduce their magnitude are both necessary. International action is being taken by the world's scientific and political communities. Because of the need for urgent action, the greatest challenge is to move rapidly to much increased energy efficiency and to non-fossil-fuel energy sources.

  3. The effects of long-term graft preservation and prostaglandin E1 on intraoperative hemodynamic changes in liver transplantation. A comparison between orthotopic and heterotopic transplantation in the pig.

    PubMed

    Blankensteijn, J D; Schlejen, P M; Groenland, T H; Terpstra, O T

    1992-09-01

    The study aimed to compare the intraoperative hemodynamic changes during orthotopic liver transplantation (OLT) with those during heterotopic liver transplantation (HLT) after different durations of cold storage of the graft. The effect of prostaglandin E1 (PGE1) on these parameters was also studied. Sixty-nine female Yorkshire pigs underwent either OLT (n = 32) or HLT (n = 37) with a graft stored for 2 hr (n = 31), 24 hr (n = 16), 48 hr (n = 7), or 72 hr (n = 15). In 16 transplantations in the various groups, PGE1 was given intravenously to both donor and recipient animals and it was added to the preservation and flushing solutions. Univariate nonparametric tests (Mann-Whitney and Wilcoxon rank-sum) were used for analysis of cardiac output (CO), mean arterial pressure (MAP), left and right ventricular minute work (LVMW, RVMW), pulmonary capillary wedge pressure (PCWP), and systemic and pulmonary vascular resistance (SVR, PVR), at different intervals during the operative procedure. For the three main variables--i.e., the type of transplantation, the use of PGE1, and the preservation time, multiple regression analysis was performed. During HLT, portal vein clamping lowered MAP and CO, while during the anhepatic phase in OLT, SVR increased and CO dropped. After recirculation of the graft, an increase in PVR and a decrease in SVR were found in both OLT and HLT. At different stages of the surgical procedure, longer graft storage time diminished CO and MAP (P less than 0.001), especially in OLT. PGE1 appeared to reduce the cardiovascular reserves needed to compensate the changes after recirculation of the graft. The observed differences in intraoperative hemodynamics between OLT and HLT can partly be attributed to differences in operative techniques. Extension of the graft preservation period resulted in poor cardiac performance, more so in OLT than HLT. The native liver in HLT might be able to metabolize the presumed myocardial depressant factors, released by the graft upon reperfusion. Prostaglandin E1 did not protect against the reperfusion syndrome. PMID:1412721

  4. Incidence of Inadvertent Intraoperative Hypothermia and Its Risk Factors in Patients Undergoing General Anesthesia in Beijing: A Prospective Regional Survey

    PubMed Central

    Deng, Xiaoming; Fan, Ting; Fu, Runqiao; Geng, Wanming; Guo, Ruihong; He, Nong; Li, Chenghui; Li, Lei; Li, Min; Li, Tianzuo; Tian, Ming; Wang, Geng; Wang, Lei; Wang, Tianlong; Wu, Anshi; Wu, Di; Xue, Xiaodong; Xu, Mingjun; Yang, Xiaoming; Yang, Zhanmin; Yuan, Jianhu; Zhao, Qiuhua; Zhou, Guoqing; Zuo, Mingzhang; Pan, Shuang; Zhan, Lujing; Yao, Min; Huang, Yuguang

    2015-01-01

    Background/Objective Inadvertent intraoperative hypothermia (core temperature <360 C) is a recognized risk in surgery and has adverse consequences. However, no data about this complication in China are available. Our study aimed to determine the incidence of inadvertent intraoperative hypothermia and its associated risk factors in a sample of Chinese patients. Methods We conducted a regional cross-sectional survey in Beijing from August through December, 2013. Eight hundred thirty patients who underwent various operations under general anesthesia were randomly selected from 24 hospitals through a multistage probability sampling. Multivariate logistic regression analyses were applied to explore the risk factors of developing hypothermia. Results The overall incidence of intraoperative hypothermia was high, 39.9%. All patients were warmed passively with surgical sheets or cotton blankets, whereas only 10.7% of patients received active warming with space heaters or electric blankets. Pre-warmed intravenous fluid were administered to 16.9% of patients, and 34.6% of patients had irrigation of wounds with pre-warmed fluid. Active warming (OR = 0.46, 95% CI 0.26–0.81), overweight or obesity (OR = 0.39, 95% CI 0.28–0.56), high baseline core temperature before anesthesia (OR = 0.08, 95% CI 0.04–0.13), and high ambient temperature (OR = 0.89, 95% CI 0.79–0.98) were significant protective factors for hypothermia. In contrast, major-plus operations (OR = 2.00, 95% CI 1.32–3.04), duration of anesthesia (1–2 h) (OR = 3.23, 95% CI 2.19–4.78) and >2 h (OR = 3.44, 95% CI 1.90–6.22,), and intravenous un-warmed fluid (OR = 2.45, 95% CI 1.45–4.12) significantly increased the risk of hypothermia. Conclusions The incidence of inadvertent intraoperative hypothermia in Beijing is high, and the rate of active warming of patients during operation is low. Concern for the development of intraoperative hypothermia should be especially high in patients undergoing major operations, requiring long periods of anesthesia, and receiving un-warmed intravenous fluids. PMID:26360773

  5. [Intraoperative crisis and surgical Apgar score].

    PubMed

    Oshiro, Masakatsu; Sugahara, Kazuhiro

    2014-03-01

    Intraoperative crisis is an inevitable event to anesthesiologists. The crisis requires effective and coordinated management once it happened but it is difficult to manage the crises properly under extreme stressful situation. Recently, it is reported that the use of surgical crisis checklists is associated with significant improvement in the management of operating-room crises in a high-fidelity simulation study. Careful preoperative evaluation, proper intraoperative management and using intraoperative crisis checklists will be needed for safer perioperative care in the future. Postoperative complication is a serious public health problem. It reduces the quality of life of patients and raises medical cost. Careful management of surgical patients is required according to their postoperative condition for preventing postoperative complications. A 10-point surgical Apgar score, calculated from intraoperative estimated blood loss, lowest mean arterial pressure, and lowest heart rate, is a simple and available scoring system for predicting postoperative complications. It undoubtedly predicts higher than average risk of postoperative complications and death within 30 days of surgery. Surgical Apgar score is a bridge between proper intraoperative and postoperative care. Anesthesiologists should make effort to reduce the postoperative complication and this score is a tool for it. PMID:24724435

  6. Radiation safety consideration during intraoperative radiation therapy.

    PubMed

    Mobit, Paul N; Rajaguru, Priyadarshini; Brewer, Michael; Baird, Michael; Packianathan, Satyaseelan; Yang, Claus Chunli

    2015-04-01

    Using in-house-designed phantoms, the authors evaluated radiation exposure rates in the vicinity of a newly acquired intraoperative radiation therapy (IORT) system: Axxent Electronic Brachytherapy System. The authors also investigated the perimeter radiation levels during three different clinical intraoperative treatments (breast, floor of the mouth and bilateral neck cancer patients). Radiation surveys during treatment delivery indicated that IORT using the surface applicator and IORT using balloons inserted into patient body give rise to exposure rates of 200 mR h(-1), 30 cm from a treated area. To reduce the exposure levels, movable lead shields should be used as they reduce the exposure rates by >95%. The authors' measurements suggest that intraoperative treatment using the 50-kVp X-ray source can be administered in any regular operating room without the need for radiation shielding modification as long as the operators utilise lead aprons and/or stand behind lead shields. PMID:25267855

  7. Intraoperative cerebral blood flow imaging of rodents

    NASA Astrophysics Data System (ADS)

    Li, Hangdao; Li, Yao; Yuan, Lu; Wu, Caihong; Lu, Hongyang; Tong, Shanbao

    2014-09-01

    Intraoperative monitoring of cerebral blood flow (CBF) is of interest to neuroscience researchers, which offers the assessment of hemodynamic responses throughout the process of neurosurgery and provides an early biomarker for surgical guidance. However, intraoperative CBF imaging has been challenging due to animal's motion and position change during the surgery. In this paper, we presented a design of an operation bench integrated with laser speckle contrast imager which enables monitoring of the CBF intraoperatively. With a specially designed stereotaxic frame and imager, we were able to monitor the CBF changes in both hemispheres during the rodent surgery. The rotatable design of the operation plate and implementation of online image registration allow the technician to move the animal without disturbing the CBF imaging during surgery. The performance of the system was tested by middle cerebral artery occlusion model of rats.

  8. Intraoperative aortic dissection in pediatric heart surgery.

    PubMed

    Hibino, Narutoshi; Harada, Yorikazu; Hiramatsu, Takeshi; Yasukochi, Satoshi; Satomi, Gengi

    2006-06-01

    Intraoperative aortic dissection occurred in a 3-year-old-boy undergoing repair of an atrial septal defect. Transesophageal echocardiography was useful for the diagnosis, and conservative medical treatment under close observation was feasible in this case which involved a limited intimal tear. PMID:16714685

  9. Nuclear probes and intraoperative gamma cameras.

    PubMed

    Heller, Sherman; Zanzonico, Pat

    2011-05-01

    Gamma probes are now an important, well-established technology in the management of cancer, particularly in the detection of sentinel lymph nodes. Intraoperative sentinel lymph node as well as tumor detection may be improved under some circumstances by the use of beta (negatron or positron), rather than gamma detection, because the very short range (∼ 1 mm or less) of such particulate radiations eliminates the contribution of confounding counts from activity other than in the immediate vicinity of the detector. This has led to the development of intraoperative beta probes. Gamma camera imaging also benefits from short source-to-detector distances and minimal overlying tissue, and intraoperative small field-of-view gamma cameras have therefore been developed as well. Radiation detectors for intraoperative probes can generally be characterized as either scintillation or ionization detectors. Scintillators used in scintillation-detector probes include thallium-doped sodium iodide, thallium- and sodium-doped cesium iodide, and cerium-doped lutecium orthooxysilicate. Alternatives to inorganic scintillators are plastic scintillators, solutions of organic scintillation compounds dissolved in an organic solvent that is subsequently polymerized to form a solid. Their combined high counting efficiency for beta particles and low counting efficiency for 511-keV annihilation γ-rays make plastic scintillators well-suited as intraoperative beta probes in general and positron probes in particular Semiconductors used in ionization-detector probes include cadmium telluride, cadmium zinc telluride, and mercuric iodide. Clinical studies directly comparing scintillation and semiconductor intraoperative probes have not provided a clear choice between scintillation and ionization detector-based probes. The earliest small field-of-view intraoperative gamma camera systems were hand-held devices having fields of view of only 1.5-2.5 cm in diameter that used conventional thallium-doped sodium iodide or sodium-doped cesium iodide scintillation detectors. Later units used 2-dimensional arrays (mosaics) of scintillation crystals connected to a position-sensitive photomultiplier tube and, more recently, semiconductors such as cadmium telluride or cadmium zinc telluride. The main problems with the early units were their very small fields of view and the resulting large number of images required to interrogate the surgical field and the difficulty in holding the device sufficiently still for the duration (up to 1 min) of the image acquisition. More recently, larger field-of-view (up to 5 × 5 cm) devices have developed which are attached to an articulating arm for easy and stable positioning. These systems are nonetheless fully portable and small enough overall to be accommodated in typical surgical suites. PMID:21440694

  10. Intraoperative BiPAP in OSA Patients.

    PubMed

    Singh, Bhavna P; Ns, Kodandaram

    2015-04-01

    Obstructive sleep apnea syndrome (OSA) is characterized by recurrent episodes of partial or complete upper airway obstructions during sleep. Severe OSA presents with a number of challenges to the anesthesiologist, the most life threatening being loss of the airway. We are reporting a case where we successfully used intraoperative bi level positive pressure ventilation (BiPAP) with moderate sedation and a regional technique in a patient with severe OSA posted for total knee replacement (TKR). A 55-year-old lady with osteoarthritis of right knee joint was posted for total knee replacement. She had severe OSA with an apnea-hypopnea index of 35. She also had moderate pulmonary hypertension due to her long standing OSA. We successfully used in her a combined spinal epidural technique with intraoperative BiPAP and sedation. She had no complications intraoperatively or post operatively and was discharged on day 5. Patients with OSA are vulnerable to sedatives, anaesthesia and analgesia which even in small doses can cause complete airway collapse. The problem, with regional techniques is that it requires excellent patient cooperation. We decided to put our patient on intraoperative BiPAP hoping that this would allow us to sedate her adequately for the surgery. As it happened we were able to successfully sedate her with slightly lesser doses of the commonly used sedatives without any episodes of desaturation, snoring or exacerbation of pulmonary hypertension. Many more trials are required before we can conclusively say that intraoperative BiPAP allows us to safely sedate OSA patients but we hope that our case report draws light on this possibility. Planning ahead and having a BiPAP machine available inside the operating may allow us to use sedatives in these patients to keep them comfortable under regional anaesthesia. PMID:26023625

  11. Intraoperative BiPAP in OSA Patients

    PubMed Central

    Singh, Bhavna P

    2015-01-01

    Obstructive sleep apnea syndrome (OSA) is characterized by recurrent episodes of partial or complete upper airway obstructions during sleep. Severe OSA presents with a number of challenges to the anesthesiologist, the most life threatening being loss of the airway. We are reporting a case where we successfully used intraoperative bi level positive pressure ventilation (BiPAP) with moderate sedation and a regional technique in a patient with severe OSA posted for total knee replacement (TKR). A 55-year-old lady with osteoarthritis of right knee joint was posted for total knee replacement. She had severe OSA with an apnea-hypopnea index of 35. She also had moderate pulmonary hypertension due to her long standing OSA. We successfully used in her a combined spinal epidural technique with intraoperative BiPAP and sedation. She had no complications intraoperatively or post operatively and was discharged on day 5. Patients with OSA are vulnerable to sedatives, anaesthesia and analgesia which even in small doses can cause complete airway collapse. The problem, with regional techniques is that it requires excellent patient cooperation. We decided to put our patient on intraoperative BiPAP hoping that this would allow us to sedate her adequately for the surgery. As it happened we were able to successfully sedate her with slightly lesser doses of the commonly used sedatives without any episodes of desaturation, snoring or exacerbation of pulmonary hypertension. Many more trials are required before we can conclusively say that intraoperative BiPAP allows us to safely sedate OSA patients but we hope that our case report draws light on this possibility. Planning ahead and having a BiPAP machine available inside the operating may allow us to use sedatives in these patients to keep them comfortable under regional anaesthesia. PMID:26023625

  12. [Unintended cooling, active warming, and microcirculation in cardiosurgical patients].

    PubMed

    Aksel'rod, B A; Trekova, N A; Guleshov, V A; Tolstova, I A; Gus'kov, D A; Babaev, M A

    2010-01-01

    The study was undertaken to compare various methods to maintain a patient's body temperature and to evaluate their impact on microcirculation during myocardial revascularization under normothermal extracorporeal circulation (NTEC). The study enrolled 50 patients with NYHA Functional Classes III-IV coronary heart disease, who underwent aortocoronary bypass surgery under NTEC. A HICO-AQUATHERM 660 water-warming unit (Hirtz, Germany) was used in Group 1 patients (n=30). A Bair Hugger air-warming unit (Arizant, U.S.A.) with a mattress located under a patient was employed in Group 2 (n=20). Intraoperative microcirculation monitoring was carried out by a laser analyzer (Lazma, Moscow). PMID:21400730

  13. Global Warming: Physics and Facts

    SciTech Connect

    Levi, B.G.; Hafemeister, D.; Scribner, R.

    1992-05-01

    This report contains papers on: A tutorial on global atmospheric energetics and the greenhouse effect; global climate models: what and how; comparison of general circulation models; climate and the earth`s radiation budget; temperature and sea level change; short-term climate variability and predictions; the great ocean conveyor; trace gases in the atmosphere: temporal and spatial trends; the geochemical carbon cycle and the uptake of fossil fuel CO{sub 2}; forestry and global warming; the physical and policy linkages; policy implications of greenhouse warming; options for lowering US carbon dioxide emissions; options for reducing carbon dioxide emissions; and science and diplomacy: a new partnership to protect the environment.

  14. Global Warming: Physics and Facts

    SciTech Connect

    Levi, B.G. ); Hafemeister, D. , Washington, DC ); Scribner, R. )

    1992-01-01

    This report contains papers on: A tutorial on global atmospheric energetics and the greenhouse effect; global climate models: what and how; comparison of general circulation models; climate and the earth's radiation budget; temperature and sea level change; short-term climate variability and predictions; the great ocean conveyor; trace gases in the atmosphere: temporal and spatial trends; the geochemical carbon cycle and the uptake of fossil fuel CO{sub 2}; forestry and global warming; the physical and policy linkages; policy implications of greenhouse warming; options for lowering US carbon dioxide emissions; options for reducing carbon dioxide emissions; and science and diplomacy: a new partnership to protect the environment.

  15. Evaluation of intraoperative radioscopy on the coronal alignment of the tibial component in primary knee arthroplasty☆

    PubMed Central

    Cobra, Hugo; Hadid, Marcio Bruno; Jácome, Daniel Torres; de Sousa, Eduardo Branco; de Paula Mozella, Alan; e Albuquerque, Rodrigo Pires

    2015-01-01

    Objectives The present study had the objective of evaluating the effect of the use of intraoperative radioscopy in cases of primary knee arthroplasty, on the final alignment of the tibial component. Methods Patients who underwent total knee arthroplasty (TKA) between April 13, 2013, and April 20, 2013, were included in the study. These patients were evaluated retrospectively and two groups were identified: one in which intraoperative radioscopy was used to assess the positioning of the tibial component during the surgery and the other in which this resource was not used. Results The mean angle of alignment of the tibial component in relation to the tibial diaphysis was greater in the group without use of intraoperative radioscopy (90.82) than in the group with radioscopy (90.63), which was a statistically significant result (p < 0.05). Conclusion Use of intraoperative radioscopy during TKA produced a better mean angle of alignment between the tibial component and the tibial diaphysis, in comparison with nonuse. PMID:26535200

  16. The Art of Intraoperative Glioma Identification

    PubMed Central

    Zhang, Zoe Z.; Shields, Lisa B. E.; Sun, David A.; Zhang, Yi Ping; Hunt, Matthew A.; Shields, Christopher B.

    2015-01-01

    A major dilemma in brain-tumor surgery is the identification of tumor boundaries to maximize tumor excision and minimize postoperative neurological damage. Gliomas, especially low-grade tumors, and normal brain have a similar color and texture, which poses a challenge to the neurosurgeon. Advances in glioma resection techniques combine the experience of the neurosurgeon and various advanced technologies. Intraoperative methods to delineate gliomas from normal tissue consist of (1) image-based navigation, (2) intraoperative sampling, (3) electrophysiological monitoring, and (4) enhanced visual tumor demarcation. The advantages and disadvantages of each technique are discussed. A combination of these methods is becoming widely accepted in routine glioma surgery. Gross total resection in conjunction with radiation, chemotherapy, or immune/gene therapy may increase the rates of cure in this devastating disease. PMID:26284196

  17. Intraoperative identification of adrenal-renal fusion.

    PubMed

    Boll, Griffin; Rattan, Rishi; Yilmaz, Osman; Tarnoff, Michael E

    2015-01-01

    Adrenal - renal fusion is a rare entity defined as incomplete encapsulation of the adrenal gland and kidney with histologically adjacent functional tissue. This report describes the first published intraoperative identification of this anomaly during laparoscopic adrenalectomy. The patient was a 59-year-old man with chronic hypertension refractory to multiple antihypertensives found to be caused by a right-sided aldosterone-producing adrenal adenoma in the setting of bilateral adrenal hyperplasia. During laparoscopic adrenalectomy, the normal avascular plane between the kidney and adrenal gland was absent. Pathologic evaluation confirmed adrenal - renal fusion without adrenal heterotopia. Identified intraoperatively, this may be misdiagnosed as invasive malignancy, and thus awareness of this anomaly may help prevent unnecessarily morbid resection. PMID:26195881

  18. Intraoperative high-dose-rate brachytherapy.

    PubMed

    Nag, Subir; Hu, Kenneth S

    2003-10-01

    Although several modalities have been discussed, a comprehensive intraoperative program should have IOERT, IOHDR, and perioperative brachytherapy facilities available to treat all sites. Interstitial brachytherapy is preferable for the treatment of gross residual tumor; IORT (IOERT for accessible sites and IOHDR for poorly accessible sites) is added to irradiate intraoperatively the surrounding margins after gross resection; and fractionated EBRT could be used in moderate doses post-operatively to irradiate the entire area of potential microscopic disease. Depending on the volume and location of the tumor, and the available expertise and equipment, IOERT, IOHDR, or perioperative brachytherapy could be used along with EBRT and surgery for the optimal management of malignancies. Finally, the best results of IOHDR are obtained when used as a conformal boost to the tumor bed after resection in conjunction with supplementary EBRT. PMID:14989134

  19. Virtual Intraoperative Cholangiogram Using WebCL.

    PubMed

    Yu, Alexander; Demirel, Doga; Halic, Tansel; Kockara, Sinan

    2016-01-01

    In this paper, we propose a Virtual Intraoperative Cholangiogram (VIC) training platform. Intraoperative Cholangiogram (IC) is an imaging technique of biliary anatomy with using fluorescent fluids sensitive to the X-Rays. The procedure is often employed to diagnose the difficult cases such as abnormal anatomy or choledocholithiasis during the laparoscopic cholecystectomy. The major challenge in cholangiogram is accurate interpretation of the X-Ray image, which requires extensive case training. However, the training platforms that support generation of various IC cases have been lacking. In this study, we developed a web based platform to generate IC images from any virtual bile duct anatomy. As the generation of X-Ray image from 3D scene is a computationally intensive task, we utilized WebCL technology to parallelize the computation for achieving real-time rates. In this work, we present details of our WebCL IC generation algorithm and benchmark results. PMID:27046623

  20. The Art of Intraoperative Glioma Identification.

    PubMed

    Zhang, Zoe Z; Shields, Lisa B E; Sun, David A; Zhang, Yi Ping; Hunt, Matthew A; Shields, Christopher B

    2015-01-01

    A major dilemma in brain-tumor surgery is the identification of tumor boundaries to maximize tumor excision and minimize postoperative neurological damage. Gliomas, especially low-grade tumors, and normal brain have a similar color and texture, which poses a challenge to the neurosurgeon. Advances in glioma resection techniques combine the experience of the neurosurgeon and various advanced technologies. Intraoperative methods to delineate gliomas from normal tissue consist of (1) image-based navigation, (2) intraoperative sampling, (3) electrophysiological monitoring, and (4) enhanced visual tumor demarcation. The advantages and disadvantages of each technique are discussed. A combination of these methods is becoming widely accepted in routine glioma surgery. Gross total resection in conjunction with radiation, chemotherapy, or immune/gene therapy may increase the rates of cure in this devastating disease. PMID:26284196

  1. Tolerance of bile duct to intraoperative irradiation

    SciTech Connect

    Sindelar, W.F.; Tepper, J.; Travis, E.L.

    1982-09-01

    In order to determine the effects of intraoperative radiation therapy of the bile duct and surrounding tissues, seven adult dogs were subjected to laparotomy and intraoperative irradiation with 11 MeV electrons. Two animals were treated at each dose level of 2000, 3000, and 4500 rads. A single dog which received a laparotomy and sham irradiation served as a control. The irradiation field consisted of a 5 cm diameter circle encompassing the extrahepatic bile duct, portal vein, hepatic artery, and lateral duodenal wall. The animals were followed clinically for mor than 18 months after treatment, and autopsies were performed on dogs that died to assess radiation-induced complications or tissue damage. All dogs developed fibrosis and mural thickening of the common duct, which appeared by 6 weeks following irradiation and which was dose-related, being mild at low doses and more severe at high doses. Hepatic changes were seen as early as 6 weeks after irradiation, consisting of periportal inflammation and fibrosis. The hepatic changes appeared earliest at the highest doses. Frank biliary cirrhosis eventually developed at all dose levels. Duodenal fibrosis appeared in the irradiation portal, being most severe at the highest doses and in some animals resulting in duodenal obstruction. No changes were observed in irradiated portions of portal vein and hepatic artery at any dose level. It was concluded that intraoperative radiation therapy delivered to the region of the common duct leads to ductal fibrosis, partial biliary obstruction with secondary hepatic changes, and duodenal fibrosis if bowel wall is included in the field. Clinical use of intraoperative radiation therapy to the bile duct in humans may require routine use of biliary and duodenal bypass to prevent obstructive complications.

  2. Intraoperative anterior cruciate ligament graft contamination.

    PubMed

    Pasque, Charles B; Geib, Timothy M

    2007-03-01

    Intraoperative anterior cruciate ligament graft contamination is a rare but potentially devastating occurrence for any surgeon to encounter. Most instances in our experience have happened when a surgeon first enters practice or is operating in a new environment with new staff. Based on the currently available literature and the senior author's personal experience with 3 cases, intraoperative cleansing of the graft followed by implantation is a reasonable option. The protocol used successfully in these 3 cases includes getting the graft off of the floor immediately, removing any suture material in the graft, cleansing the graft for 15 to 30 minutes each in chlorohexidine and triple antibiotic solution, followed by a normal saline rinse. All graft sutures should then be replaced. The graft should then be resized and the tibial and femoral tunnels adjusted if needed. After implantation of the graft, additional intraoperative and postoperative intravenous antibiotic and/or oral antibiotic administration is also recommended for the first 1 to 2 weeks. Close clinical follow-up is also very important the first 6 weeks postoperatively and should include candid communication with the patient and family. PMID:17349486

  3. The effect of ephedrine on intraoperative hypothermia

    PubMed Central

    Jo, Youn Yi; Kim, Ji Young; Kim, Joon-Sik; Kwon, Youngjun

    2011-01-01

    Background Prevention of intraoperative hypothermia has become a standard of operative care. Since ephedrine has a thermogenic effect and it is frequently used to treat hypotension during anesthesia, this study was designed to determine the effect of ephedrine on intraoperative hypothermia of patients who are undergoing spine surgery. Methods Twenty-four patients were randomly divided to receive an ephedrine (the ephedrine group, n = 12) or normal saline (the control group, n = 12) infusion for 2 h. The esophageal temperature (the core temperature), the index finger temperature (the peripheral temperature) and the hemodynamic variables such as the mean blood pressure and heart rate were measured every 15 minutes after the intubation. Results At the end of the study period, the esophageal temperature and hemodynamic variables were significantly decreased in the control group, whereas those in the ephedrine group were stably maintained. The index finger temperature was significantly lower in the ephedrine group compared to that in the control group, suggesting the prevention of core-to-peripheral redistribution of the heat as the cause of temperature maintenance. Conclusions An intraoperative infusion of ephedrine minimized the decrease of the core temperature and it stably maintained the hemodynamic variables during spine surgery with the patient under general anesthesia. PMID:21602974

  4. Estimations of global warming potentials from computational chemistry calculations for CH(2)F(2) and other fluorinated methyl species verified by comparison to experiment.

    PubMed

    Blowers, Paul; Hollingshead, Kyle

    2009-05-21

    In this work, the global warming potential (GWP) of methylene fluoride (CH(2)F(2)), or HFC-32, is estimated through computational chemistry methods. We find our computational chemistry approach reproduces well all phenomena important for predicting global warming potentials. Geometries predicted using the B3LYP/6-311g** method were in good agreement with experiment, although some other computational methods performed slightly better. Frequencies needed for both partition function calculations in transition-state theory and infrared intensities needed for radiative forcing estimates agreed well with experiment compared to other computational methods. A modified CBS-RAD method used to obtain energies led to superior results to all other previous heat of reaction estimates and most barrier height calculations when the B3LYP/6-311g** optimized geometry was used as the base structure. Use of the small-curvature tunneling correction and a hindered rotor treatment where appropriate led to accurate reaction rate constants and radiative forcing estimates without requiring any experimental data. Atmospheric lifetimes from theory at 277 K were indistinguishable from experimental results, as were the final global warming potentials compared to experiment. This is the first time entirely computational methods have been applied to estimate a global warming potential for a chemical, and we have found the approach to be robust, inexpensive, and accurate compared to prior experimental results. This methodology was subsequently used to estimate GWPs for three additional species [methane (CH(4)); fluoromethane (CH(3)F), or HFC-41; and fluoroform (CHF(3)), or HFC-23], where estimations also compare favorably to experimental values. PMID:19402663

  5. Osteoid osteoma: localization by intraoperative magnification scintigraphy.

    PubMed

    Taylor, G A; Shea, N; O'Brien, T; Hall, J E; Treves, S T

    1986-01-01

    Surgical localization of osteoid osteomas is a major problem in the diagnosis and therapy of this lesion. Visual, tactile, and radiographic localization is often equivocal and as a consequence incomplete excision of the tumor, or excessive removal of bone may result. We performed magnification intraoperative bone scintigraphy using a portable gamma camera and a radioactive pointer in six patients with osteoid osteoma. Accurate localization and complete removal of the tumor was achieved in all six with only minimal delays in the surgical procedure. The advantages of this technique and recommendations for its use are discussed. PMID:3725449

  6. In vivo virtual intraoperative surgical photoacoustic microscopy

    NASA Astrophysics Data System (ADS)

    Han, Seunghoon; Lee, Changho; Kim, Sehui; Jeon, Mansik; Kim, Jeehyun; Kim, Chulhong

    2013-11-01

    We developed a virtual intraoperative surgical photoacoustic microscopy system by combining with a commercial surgical microscope and photoacoustic microscope (PAM). By sharing the common optical path in the microscope and PAM system, we could acquire the PAM and microscope images simultaneously. Moreover, by employing a beam projector to back-project 2D PAM images onto the microscope view plane as augmented reality, the conventional microscopic and 2D cross-sectional PAM images are concurrently mapped on the plane via an ocular lens of the microscope in real-time. Further, we guided needle insertion into phantom ex vivo and mice skins in vivo.

  7. In vivo virtual intraoperative surgical photoacoustic microscopy

    SciTech Connect

    Han, Seunghoon Kim, Sehui Kim, Jeehyun E-mail: chulhong@postech.edu; Lee, Changho Jeon, Mansik; Kim, Chulhong E-mail: chulhong@postech.edu; Department of Biomedical Engineering, The State University of New York at Buffalo, Buffalo, New York 14221

    2013-11-11

    We developed a virtual intraoperative surgical photoacoustic microscopy system by combining with a commercial surgical microscope and photoacoustic microscope (PAM). By sharing the common optical path in the microscope and PAM system, we could acquire the PAM and microscope images simultaneously. Moreover, by employing a beam projector to back-project 2D PAM images onto the microscope view plane as augmented reality, the conventional microscopic and 2D cross-sectional PAM images are concurrently mapped on the plane via an ocular lens of the microscope in real-time. Further, we guided needle insertion into phantom ex vivo and mice skins in vivo.

  8. Self-inflicted nail-gun injury with cranial penetration and use of intraoperative computed tomography

    PubMed Central

    Carnevale, Joseph A.; Morrison, John F.; Choi, David B.; Klinge, Petra M.; Cosgrove, G. Rees; Oyelese, Adetokunbo A.

    2016-01-01

    Background: Management of penetrating cranial trauma remains a high acuity and imaging intense neurosurgical disorder. Imaging of vital structures, including angiography, is typically conducted to understand the proximity of vital structures in comparison to a foreign body and prepare for intraoperative complications such as hemorrhage. Preservation of function following initial injury in cases where minimal neurological deficit exists is essential. Case Description: Here, we present a case using intraoperative computed tomography to assist in early detection and resolution of hemorrhage in the surgical management of an intact patient with self-inflicted penetrating cranial trauma. Conclusions: This method may aid in early detection of hemorrhage and prevention of consequential neurological deterioration or emergent need for secondary surgery. PMID:27213112

  9. Application experience of intraoperative neuromonitoring in thyroidectomy

    PubMed Central

    Zheng, Haitao; Jiang, Lixin; Wang, Xuewen; Hu, Jinchen; Ning, Jinrao; Wang, Dong; Li, Baoyuan; Zheng, Guibin; Xu, Jie

    2015-01-01

    Objective: The aim of this study is to summarize the experience of intraoperative neuromonitoring system for monitoring and protection of recurrent laryngeal nerve during thyroid surgery. Methods: There were 220 cases in this study, male 53, female 167, mean age 38.2 years old. 85 cases in the study had thyroid cancer, 19 cases had thyroid benign tumor, 90 cases had thyroid goiter, 3 cases had Hashimoto’s diseases, and 23 cases had hyperthyroidism. The tumor diameters were over than 5 cm in 113 cases. In the procedure, two recording needle electrodes were put into cricothyroid muscle; one stimulator electrodes was explored in tracheo-asophageal groove, if recurrent laryngeal nerves were right there or near, doctors could see the electromyogram and hear the toot honk. With careful dissection, recurrent laryngeal nerve could be found out till explored into the larynx site. Results: 207 cases (278 sizes) of 220 were finished, electromyogram was not drawn out in 13 cases; 9 cases were false-negative because of system and anesthesia questions; needle electrodes cannot be put in properly in 4 cases because of cricothyroid muscle cancer invasion. No permanent recurrent laryngeal nerve paralysis occurred, 2 cases with transient nerve paralysis recovered in one month. Conclusion: The intraoperative neuromonitoring system can avoid damage of the recurrent laryngeal nerves when exposing the recurrent laryngeal nerve in the whole operation, therefore, with less medical complications. PMID:26885214

  10. Intraoperative MRI in pediatric brain tumors.

    PubMed

    Choudhri, Asim F; Siddiqui, Adeel; Klimo, Paul; Boop, Frederick A

    2015-09-01

    Intraoperative magnetic resonance imaging (iMRI) has emerged as an important tool in guiding the surgical management of children with brain tumors. Recent advances have allowed utilization of high field strength systems, including 3-tesla MRI, resulting in diagnostic-quality scans that can be performed while the child is on the operating table. By providing information about the possible presence of residual tumor, it allows the neurosurgeon to both identify and resect any remaining tumor that is thought to be safely accessible. By fusing the newly obtained images with the surgical guidance software, the images have the added value of aiding in navigation to any residual tumor. This is important because parenchyma often shifts during surgery. It also gives the neurosurgeon insight into whether any immediate postoperative complications have occurred. If any complications have occurred, the child is already in the operating room and precious minutes lost in transport and communications are saved. In this article we review the three main approaches to an iMRI system design. We discuss the possible roles for iMRI during intraoperative planning and provide guidance to help radiologists and neurosurgeons alike in the collaborative management of these children. PMID:26346145

  11. Intracardiac leiomyomatosis presenting as an intraoperative consultation.

    PubMed

    Alves, António Joaquim Teixeira; Ferreira, Marco António; Gallego-Poveda, Javier; Matos, Ana; Costa-Silva, Artur; Nobre, Ângelo; Lopez-Beltran, António

    2016-06-01

    Intravenous leiomyomatosis (IVL) is an extremely rare variant of leiomyoma in which nodular masses of tumor grow within venous channels. Rarely, the tumor can reach the vena cava and right heart. We present a case of a 45-year-old woman, admitted with rapidly evolving exertional dyspnea. Cardiac ultrasonography revealed a "mass in the right chambers". She was submitted to right atriotomy plus tumorectomy, with intraoperative consultation requested. Grossly, the tumor was polypoid, firm, with a smooth surface. The frozen section showed a lesion composed of tortuous vessels and some areas with a fibrillar eosinophil extracellular matrix and others with spindle cells, without significant atypia, mitosis or necrosis. The diagnosis was deferred for definitive paraffin sections. In the definitive H&E and immunohistochemical stains, the case was diagnosed as an IVL and confirmed in the hysterectomy specimen. This is the first case report describing an intraoperative consultation of an intracardiac leiomyomatosis. Clinical information and pathologist awareness to this entity are essential for the correct diagnosis in frozen section. PMID:27067811

  12. Improved Visualization of Intracranial Vessels with Intraoperative Coregistration of Rotational Digital Subtraction Angiography and Intraoperative 3D Ultrasound

    PubMed Central

    Podlesek, Dino; Meyer, Tobias; Morgenstern, Ute; Schackert, Gabriele; Kirsch, Matthias

    2015-01-01

    Introduction Ultrasound can visualize and update the vessel status in real time during cerebral vascular surgery. We studied the depiction of parent vessels and aneurysms with a high-resolution 3D intraoperative ultrasound imaging system during aneurysm clipping using rotational digital subtraction angiography as a reference. Methods We analyzed 3D intraoperative ultrasound in 39 patients with cerebral aneurysms to visualize the aneurysm intraoperatively and the nearby vascular tree before and after clipping. Simultaneous coregistration of preoperative subtraction angiography data with 3D intraoperative ultrasound was performed to verify the anatomical assignment. Results Intraoperative ultrasound detected 35 of 43 aneurysms (81%) in 39 patients. Thirty-nine intraoperative ultrasound measurements were matched with rotational digital subtraction angiography and were successfully reconstructed during the procedure. In 7 patients, the aneurysm was partially visualized by 3D-ioUS or was not in field of view. Post-clipping intraoperative ultrasound was obtained in 26 and successfully reconstructed in 18 patients (69%) despite clip related artefacts. The overlap between 3D-ioUS aneurysm volume and preoperative rDSA aneurysm volume resulted in a mean accuracy of 0.71 (Dice coefficient). Conclusions Intraoperative coregistration of 3D intraoperative ultrasound data with preoperative rotational digital subtraction angiography is possible with high accuracy. It allows the immediate visualization of vessels beyond the microscopic field, as well as parallel assessment of blood velocity, aneurysm and vascular tree configuration. Although spatial resolution is lower than for standard angiography, the method provides an excellent vascular overview, advantageous interpretation of 3D-ioUS and immediate intraoperative feedback of the vascular status. A prerequisite for understanding vascular intraoperative ultrasound is image quality and a successful match with preoperative rotational digital subtraction angiography. PMID:25803318

  13. Intraoperative video panendoscopy for diagnosing sites of chronic intestinal bleeding.

    PubMed

    Flickinger, E G; Stanforth, A C; Sinar, D R; MacDonald, K G; Lannin, D R; Gibson, J H

    1989-01-01

    Intraoperative video panendoscopy was performed in 14 patients with chronic, recurrent gastrointestinal bleeding. All of the study patients had undergone extensive and expensive diagnostic testing including multiple radiographic contrast studies of the gastrointestinal tract, upper and lower endoscopy, nuclear bleeding scans, and selective mesenteric angiography without definition of the bleeding source. Intraoperative video panendoscopy, employing a segmental advance and look technique, allowed visualization and transillumination of the entire gut and identified mucosal disease in 13 patients (93 percent). Angiodysplasia of the colon and small intestine was the most common pathologic finding. Intraoperative video panendoscopy significantly influenced the operation performed in 13 patients (93 percent). Postoperative complications were minimal, with none being directly attributable to intraoperative video panendoscopy. Bleeding was totally controlled in 10 patients (71 percent) during a mean follow-up period of 25 months. Intraoperative video panendoscopy is a valuable technique for assisting in the management of the patient with recurrent gastrointestinal bleeding. PMID:2491932

  14. Comparison between whole-body vibration, light-emitting diode, and cycling warm-up on high-intensity physical performance during sprint bicycle exercise.

    PubMed

    Teles, Maria C; Fonseca, Ivana A T; Martins, Jeanne B; de Carvalho, Marielle M; Xavier, Murilo; Costa, Sidney J; de Avelar, Núbia C P; Ribeiro, Vanessa G C; Salvador, Fabiano S; Augusto, Leonardo; Mendonça, Vanessa A; Lacerda, Ana C R

    2015-06-01

    The purpose of this study was to compare the effects of light-emitting diode (LED) irradiation and whole-body vibration (WBV) delivered either in isolation or combination (LED + WBV), warm-up (WU), and a control (C) treatment on performance during a sprint bicycle exercise. Ten cyclists performed a 30-second sprint cycle test under these conditions. The LED light was applied at 4 points bilaterally. Whole-body vibration consisted of 5 minutes of squats associated with WBV. LED + WBV consisted of WBV followed by LED therapy. Warm-up consisted of 17 minutes of moderate-intensity bicycle exercise. Control consisted of 10 minutes at rest. Blood lactate (BL) and ammonia (BA) levels and skin temperature (ST) were determined. Peak power (842 ± 117 vs. 800 ± 106 vs. 809 ± 128 W [p = 0.02 and p = 0.01]), relative power (12.1 ± 1.0 vs. 11.5 ± 0.9 vs. 11.6 ± 1.0 W·kg [p = 0.02 and p = 0.02]), and relative work (277 ± 23 vs. 263 ± 24 vs. 260 ± 23 J·kg [p = 0.02 and p = 0.003]) were higher in the WU group compared with the control and LED groups. In the LED + WBV group, peak (833 ± 115 vs. 800 ± 106 W [p = 0.02]) and relative (11.9 ± 0.9 vs. 11.5 ± 0.9 W·kg [p = 0.02]) power were higher than those in the control group, and relative work (272 ± 22 vs. 260 ± 23 J·kg [p = 0.02]) were improved compared with the LED group. There were no differences for BL, BA, and ST. The findings of this study confirmed the effectiveness of a warm-up as a preparatory activity and demonstrated that LED + WBV and WBV were as effective as WU in improving cyclist performance during a sprint bicycle exercise. PMID:25764492

  15. Surgical Pathology and Intraoperative Consultation: An Audit

    PubMed Central

    GOLAM, Mostafa; QUEEN, Zarat

    2015-01-01

    Background: While intraoperative consultation has been used in Bangladesh for a long period of time, to date, there has been no published reporting on the performance of frozen sections. The current audit evaluates the performance of frozen sections in a well reputed medical center in Bangladesh, Anowara Medical Services. Objective: This retrospective study has been designed to measure the accuracy of frozen section diagnosis in a medical center in a third-world country, where many surgical procedures rely on intraoperative consultation. Methods: A series of 1379 intra- and peri-operative frozen section cases, from 2007 to 2014, was reviewed. Intraoperative tissue specimens received at Anowara Medical Services were processed for frozen sections. After examination of the frozen section that yielded the initial frozen section diagnoses, the frozen tissues were reprocessed for regular paraffin sectioning. These paraffin sections were examined by a second pathologist, and a final diagnosis was issued. The frozen section diagnosis and final diagnoses of all cases were retrospectively analysed to determine the accuracy of frozen section examination. Results: Overall, accurate diagnosis was made on frozen sections in 98.2% of the cases. The discrepant diagnoses were all clinically significant, i.e., there were discrepancies between benign and malignant diagnoses on frozen and paraffin sections. In 1% of the cases, diagnosis was deferred. Fifty percent of the deferred cases were benign. Two cases, received in formalin, were excluded. In both cases, the diagnosis was positive for malignancy. The number of false negative results (4 false negatives) was slightly lower than that of false positives (5 false positives). Specificity and sensitivity of 99.3% and 99.4% were achieved, respectively. In this study, the positive predictive value was 99.2% and the negative predictive value was 99.5%. Over the years, the number of discrepant diagnoses remained fairly constant. Conclusion: The present method has a satisfactory rate of accuracy of frozen section diagnosis, which is comparable to other remote and recent published series. The results of this study offer a testament to the reliability of frozen section diagnosis rendered by qualified pathologists in Bangladesh and may serve as evidence in building confidence among the surgeons who use this service for improved patient care. PMID:26715906

  16. Relationship of Postoperative Recatheterization and Intraoperative Bladder Distention Volume in Holmium Laser Enucleation of the Prostate for Benign Prostatic Hyperplasia

    PubMed Central

    Kim, Hyeon Jun; Lee, Han Yi; Song, Sang Hun

    2013-01-01

    Purpose The purpose of this study was to identify the risk factors for recatheterization after holmium laser enucleation of the prostate (HoLEP). Materials and Methods A total of 166 consecutive patients treated with HoLEP by a single surgeon from January 2010 to June 2011 were enrolled in this study. We collected data on preoperative and intraoperative parameters, including intraoperative bladder distention volume. The patients were divided into two groups. Group 1 included patients who voided successfully after removal of the catheter, and group 2 included patients who required recatheterization. Analysis and comparison of the perioperative parameters of both groups was performed for identification of risk factors for recatheterization. Results Recatheterization was required in 9 of 166 (5.4%) patients. No significant differences in age or preoperative parameters, including prostate-specific antigen, prostate volume, International Prostate Symptom Score, peak flow rate, postvoid residual urine, maximal bladder capacity, and Abrahams Griffiths number, were observed between the two groups. Of the intraoperative parameters, intraoperative bladder distention volume was significantly smaller in group 1 than in group 2 (700.65 mL vs. 897.78 mL, p<0.001). In the multivariate logistic regression analysis, after adjustment for other variables, intraoperative bladder distention volume was found to be a statistically significant risk factor for postoperative recatheterization (hazard ratio, 1.006; confidence interval, 1.002 to 1.010; p=0.002). Conclusions Nine of 166 (5.4%) patients failed to void after HoLEP and required catheterization. Intraoperative bladder distention volume was found to be a statistically significant risk factor for recatheterization in this patient group. PMID:23549294

  17. [Intraoperative neurophysiological monitoring improves outcome in neurosurgery].

    PubMed

    Sarnthein, J; Krayenbühl, N; Actor, B; Bozinov, O; Bernays, R

    2012-01-18

    Intraoperative Neurophysiological Mo-nitoring (IONM) identifies eloquent areas or nerves fibers during neurosurgical interventions and monitors their function. For several interventions IONM has become mandatory in neurosurgery. IONM increases patient safety during surgery as the risk of neurological deficits is reduced. Safer surgery reduces the time needed for the intervention and thereby reduces risk. IONM contributes to complete resection of tumors, which in turn prolongs patients' survival. Complicated surgical interventions associated with an elevated risk of neurological deficits have only become possible due to IONM. IONM comprises a variety of procedures that are selected for a particular intervention. With appropriate selection of the procedures IONM has been shown to improve neurological and functional outcome after neurosurgical interventions. PMID:22252591

  18. Optical technologies for intraoperative neurosurgical guidance.

    PubMed

    Valdés, Pablo A; Roberts, David W; Lu, Fa-Ke; PhD; Golby, Alexandra

    2016-03-01

    Biomedical optics is a broadly interdisciplinary field at the interface of optical engineering, biophysics, computer science, medicine, biology, and chemistry, helping us understand light-tissue interactions to create applications with diagnostic and therapeutic value in medicine. Implementation of biomedical optics tools and principles has had a notable scientific and clinical resurgence in recent years in the neurosurgical community. This is in great part due to work in fluorescence-guided surgery of brain tumors leading to reports of significant improvement in maximizing the rates of gross-total resection. Multiple additional optical technologies have been implemented clinically, including diffuse reflectance spectroscopy and imaging, optical coherence tomography, Raman spectroscopy and imaging, and advanced quantitative methods, including quantitative fluorescence and lifetime imaging. Here we present a clinically relevant and technologically informed overview and discussion of some of the major clinical implementations of optical technologies as intraoperative guidance tools in neurosurgery. PMID:26926066

  19. Intraoperative evoked potential monitoring in acetabular surgery.

    PubMed

    Calder, H B; Mast, J; Johnstone, C

    1994-08-01

    The effectiveness of intraoperative sciatic nerve monitoring was evaluated for 88 consecutive patients undergoing open reduction and internal fixation for acetabular fractures. Intervention outcomes and pre and postoperative electrophysiologic status were compared to postoperative functional findings. Only 2% of the patients demonstrated iatrogenic sciatic nerve palsies. Functional and evoked potential findings were in agreement for 89% of the patients with postoperative palsies, while 26% of the functionally normal patients showed abnormal evoked potentials. Intervention occurred in 55 surgeries; 80% of interventions involved the peroneal nerve. Forty one of the 55 patients who had interventions based on evoked potential results showed recovery of responses to baseline. Of the 14 patients with incomplete intervention recovery, 11 showed impaired postoperative responses. Patients with preoperative evoked potential abnormalities did not show increased susceptibility to iatrogenic evoked potential changes. PMID:8050225

  20. Intraoperative radiation therapy in recurrent ovarian cancer

    SciTech Connect

    Yap, O.W. Stephanie . E-mail: stbeast@stanford.edu; Kapp, Daniel S.; Teng, Nelson N.H.; Husain, Amreen

    2005-11-15

    Purpose: To evaluate disease outcomes and complications in patients with recurrent ovarian cancer treated with cytoreductive surgery and intraoperative radiation therapy (IORT). Methods and Materials: A retrospective study of 24 consecutive patients with ovarian carcinoma who underwent secondary cytoreduction and intraoperative radiation therapy at our institution between 1994 and 2002 was conducted. After optimal cytoreductive surgery, IORT was delivered with orthovoltage X-rays (200 kVp) using individually sized and beveled cone applications. Outcomes measures were local control of disease, progression-free interval, overall survival, and treatment-related complications. Results: Of these 24 patients, 22 were available for follow-up analysis. Additional treatment at the time of and after IORT included whole abdominopelvic radiation, 9; pelvic or locoregional radiation, 5; chemotherapy, 6; and no adjuvant treatment, 2. IORT doses ranged from 9-14 Gy (median, 12 Gy). The anatomic sites treated were pelvis (sidewalls, vaginal cuff, presacral area, anterior pubis), para-aortic and paracaval lymph node beds, inguinal region, or porta hepatitis. At a median follow-up of 24 months, 5 patients remain free of disease, whereas 17 patients have recurred, of whom 4 are alive with disease and 13 died from disease. Five patients recurred within the radiation fields for a locoregional relapse rate of 32% and 12 patients recurred at distant sites with a median time to recurrence of 13.7 months. Five-year overall survival was 22% with a median survival of 26 months from time of IORT. Nine patients (41%) experienced Grade 3 toxicities from their treatments. Conclusion: In carefully selected patients with locally recurrent ovarian cancer, combined IORT and tumor reductive surgery is reasonably tolerated and may contribute to achieving local control and disease palliation.

  1. Intraoperative urinary cyclic AMP monitoring in primary hyperparathyroidism.

    PubMed Central

    Schenk, W G; Wills, M; MacLeod, M S; Hanks, J B

    1993-01-01

    OBJECTIVE: This study examined the utility of intraoperative urinary cyclic 3'5' adenosine monophosphate (UcAMP), an indicator of parathyroid (PTH) hormone end-organ activity, as a "biochemical frozen section," signaling the real-time resolution of PTH hyperactivity during surgery for primary hyperparathyroidism. SUMMARY BACKGROUND DATA: The unsuccessful initial neck exploration for primary hyperparathyroidism, leaving the patient with persistent hyperfunctioning parathyroid tissue, results in part from the surgeon's inability intraoperatively to correlate a gland's gross appearance and size estimation with physiologic function. Preoperative imaging, intraoperative imaging, and intraoperative histologic/cytologic surveillance have not resolved this dilemma. METHODS: Twenty-seven patients underwent a prospective intraoperative UcAMP monitoring protocol. The patients all had a clinical diagnosis of primary hyperparathyroidism and an average preoperative serum calcium of 12.0 +/- 0.3 mg/dl. UcAMP was assayed intraoperatively using 20-minute nonequilibrium radioimmunoassay providing real-time feedback to the operating team. RESULTS: All patients had an elevated UcAMP confirming PTh hyperactivity at the beginning of the procedure. One patient, subsequently found to have an supernumerary ectopic adenoma, had four normal glands identified intraoperatively, and his intraoperative UcAMP values corroborated persistent hyperparathyroidism, the UcAMP of the remaining 26 patients decreased from 7.0 +/- 1.1 to 2.7 +/- 0.7 nm.dl GF (p < .00005) after complete adenoma excision, and they remain normocalcemic. The protocol provided useful and relevant information to the operating team, and aided in surgical decision-making, in 10 of the 27 cases (37%). CONCLUSION: Intraoperative biochemical surveillance with ucAMP monitoring reliably signals resolution of PTH hyperfunction. It is a useful adjunct to the surgeon's skill, judgment, and experience in parathyroid surgery. PMID:8387765

  2. Goal-directed therapy in intraoperative fluid and hemodynamic management

    PubMed Central

    Gutierrez, Maria Cristina; Moore, Peter G.; Liu, Hong

    2013-01-01

    Intraoperative fluid management is pivotal to the outcome and success of surgery, especially in high-risk procedures. Empirical formula and invasive static monitoring have been traditionally used to guide intraoperative fluid management and assess volume status. With the awareness of the potential complications of invasive procedures and the poor reliability of these methods as indicators of volume status, we present a case scenario of a patient who underwent major abdominal surgery as an example to discuss how the use of minimally invasive dynamic monitoring may guide intraoperative fluid therapy. PMID:24086168

  3. High-global warming potential F-gas emissions in California: comparison of ambient-based versus inventory-based emission estimates, and implications of refined estimates.

    PubMed

    Gallagher, Glenn; Zhan, Tao; Hsu, Ying-Kuang; Gupta, Pamela; Pederson, James; Croes, Bart; Blake, Donald R; Barletta, Barbara; Meinardi, Simone; Ashford, Paul; Vetter, Arnie; Saba, Sabine; Slim, Rayan; Palandre, Lionel; Clodic, Denis; Mathis, Pamela; Wagner, Mark; Forgie, Julia; Dwyer, Harry; Wolf, Katy

    2014-01-21

    To provide information for greenhouse gas reduction policies, the California Air Resources Board (CARB) inventories annual emissions of high-global-warming potential (GWP) fluorinated gases, the fastest growing sector of greenhouse gas (GHG) emissions globally. Baseline 2008 F-gas emissions estimates for selected chlorofluorocarbons (CFC-12), hydrochlorofluorocarbons (HCFC-22), and hydrofluorocarbons (HFC-134a) made with an inventory-based methodology were compared to emissions estimates made by ambient-based measurements. Significant discrepancies were found, with the inventory-based emissions methodology resulting in a systematic 42% under-estimation of CFC-12 emissions from older refrigeration equipment and older vehicles, and a systematic 114% overestimation of emissions for HFC-134a, a refrigerant substitute for phased-out CFCs. Initial, inventory-based estimates for all F-gas emissions had assumed that equipment is no longer in service once it reaches its average lifetime of use. Revised emission estimates using improved models for equipment age at end-of-life, inventories, and leak rates specific to California resulted in F-gas emissions estimates in closer agreement to ambient-based measurements. The discrepancies between inventory-based estimates and ambient-based measurements were reduced from -42% to -6% for CFC-12, and from +114% to +9% for HFC-134a. PMID:24328112

  4. Discontinuation of Living Donor Liver Transplantation due to Donor's Intraoperative Latex-Induced Anaphylactic Shock

    PubMed Central

    Shinoda, Masahiro; Tanabe, Minoru; Nagao, Keisuke; Kitago, Minoru; Fujisaki, Hiroto; Odaira, Masanori; Kawachi, Shigeyuki; Itano, Osamu; Obara, Hideaki; Matsubara, Kentaro; Shimojima, Naoki; Fuchimoto, Yasushi; Hoshino, Ken; Amagai, Masayuki; Kuroda, Tatsuo; Kitagawa, Yuko

    2012-01-01

    We report on a 33-year-old female liver donor candidate who developed intraoperative latex-induced anaphylactic shock during surgery for living donor transplantation. She was the mother of the organ recipient, who was a 9-year-old boy with biliary atresia. We planned extended lateral segmentectomy for her. Although we dissected the ligament around the left lobe, the systolic blood pressure suddenly dropped and her body became flushed and warm. We administered transfusion and an ephedrine injection to recover the blood pressure. Because she recovered after the treatment, we restarted the procedure. However, she went into shock again within a few minutes. We decided to discontinue the operation. Postoperative blood tests revealed an increase in IgE-RAST and basophil activation, suggesting that the anaphylactic shock was induced by latex. Because latex allergy has become a public health problem, this allergy should be kept in mind as a potential donor operation risk. PMID:23294079

  5. Comparison of scarab grub populations and associated pathogens and parasitoids in warm- or cool-season grasses used on transitional zone golf courses.

    PubMed

    Redmond, Carl T; Williams, David W; Potter, Daniel A

    2012-08-01

    Seven different turfgrass species or mixes used on golf courses in the United States' transitional climatic zone were maintained as randomized and replicated plots in separate stands mowed at fairway (1.6 cm) or rough (6.4 cm) cutting heights and sampled in autumn to assess the density and species composition of scarab grubs; incidence of disease and parasitism thereof; and extent of turf damage from foraging insectivorous skunks, Mephitis mephitis. Influence of grass species on parasitism by spring or autumn-active tiphiid wasps was further assessed on implanted grubs in open enclosures. Masked chafers (Cyclocephala spp.) were three-fold more abundant than Japanese beetle, Popillia japonica Newman, grubs in plots of Zoysia and Cynodon sp. mowed at fairway height, and P. japonica were five-fold more abundant than masked chafer grubs in cool-season turf plots mowed at rough height. Phyllophaga spp. accounted for <1% of grubs in the samples. Milky disease bacteria (Paenibacillus sp.) were the predominant pathogens of Cyclocephala spp., followed by Serratia sp. bacteria and gregarines (Stictospora cf. villani). Cyclocephala grub densities, milky disease incidence (25%), and parasitism by the native tiphiid Tiphia pygidialis Alien (10-12%) were especially high in zoysiagrass. Japanese beetle grubs were infected by Paenibacillus, Serratia, Stictospora, and microsporidia (Ovavesicula sp.), but incidence of individual pathogens was relatively low (<6%) and similar among grasses within each stand. Few nematode-infected grubs were found. Skunk damage was mainly in the cool-season fairway-height grasses, probably reflecting difficulty in foraging in the much tougher stolons and rhizomes of the warm season turfgrasses. The degree of natural suppression of scarab grubs provided by endemic pathogens or parasitoids is unlikely to be compromised by the grass species used on a particular site. PMID:22928312

  6. Development of a risk assessment tool for intraoperative pressure ulcers.

    PubMed

    Price, Molly C; Whitney, Joanne D; King, Cecil A; Doughty, Dorothy

    2005-01-01

    This article discusses the current literature related to intraoperative and preoperative risk factors for pressure ulcer development. Although surgical patients have a high risk of pressure ulcer development, the intraoperative period of patient care has often been missed as a time of increased risk. Pressure ulcers, which may originate in the operating room, may be incorrectly blamed on postoperative areas of care resulting from delay of pressure ulcer demarcation. In the literature review, current risk assessment tools do not adequately address intraoperative risk factors. A risk assessment tool that incorporates the specific variables relevant to the preoperative and intraoperative environment is proposed based on existing literature. A pilot study of the tool was done testing for intrarater reliability. PMID:15718953

  7. Intraoperative interstitial implantation of Iridium 192 in the breast

    SciTech Connect

    Mansfield, C.M.; Jewell, W.R.

    1984-02-01

    Intraoperative interstitial implantation of iridium 192 during a lumpectomy for carcinoma of the breast has been well tolerated by the patient. This procedure has decreased the need for anesthesia and repeat hospitalization.

  8. Heat sensitive microbubbles for intraoperative assessment of cancer ablation margin

    NASA Astrophysics Data System (ADS)

    Huang, Jiwei; Xu, Jeff S.; Schmidt, Carl; Xu, Ronald X.

    2012-03-01

    We developed a heat-sensitive microbubble (HSM) agent for intraoperative assessment of thermal ablation margins in cancer ablation therapies. The HSM agent, comprising a core of liquid perfluorocarbon (PFC) compound and a shell of biodegradable poly lactic-coglycolic acid (PLGA), was fabricated using an emulsion evaporation method. In our previous study, significant increase of ultrasound contrast was observed after heat activation of HSMs. In this study, intraoperative ultrasonic assessment of thermal ablation margins by HSMs was demonstrated in vivo in a pig model. HSMs were delivered to the pig liver by portal vein injection. Liver ablation was done using a RF ablation probe. Intraoperative ultrasound imaging with HSMs clearly delineated the ablation margin. Fluorescence images of liver tissue samples confirmed the existence and activation of HSMs. This result demonstrated that the HSM agent can be potentially utilized as a multimodal contrast agent for intraoperative ultrasonic and fluorescence assessment of thermal ablation margins in cancer ablation therapies.

  9. Role of intra-operative contrast-enhanced ultrasound (CEUS) in robotic-assisted nephron-sparing surgery.

    PubMed

    Alenezi, Ahmad N; Karim, Omer

    2015-03-01

    This review examines studies of intra-operative contrast-enhanced ultrasound (CEUS) and its emerging role and advantages in robotic-assisted nephron-sparing surgery. Contrast-enhanced ultrasound is a technology that combines the use of second-generation contrast agents consisting of microbubbles with existent ultrasound techniques. Until now, this novel technology has aided surgeons with procedures involving the liver. However, with recent advances in the CEUS technique and the introduction of robotics in nephron-sparing surgery, CEUS has proven to be efficacious in answering several clinical questions with respect to the kidneys. In addition, the introduction of the microbubble-based contrast agents has increased the image quality and signal uptake by the ultrasound probe. This has led to better, enhanced scanning of the macro and microvasculature of the kidneys, making CEUS a powerful diagnostic modality. This imaging method is capable of further lowering the learning curve and warm ischemia time (WIT) during robotic-assisted nephron-sparing surgery, with its increased level of capillary perfusion and imaging. CEUS has the potential to increase the sensitivity and specificity of intra-operative images, and can significantly improve the outcome of robotic-assisted nephron-sparing surgery by increasing the precision and diagnostic insight of the surgeon. The purpose of this article is to review the practical and potential uses of CEUS as an intra-operative imaging technique during robotic-assisted nephron-sparing surgery. PMID:25722751

  10. High-dose-rate remote afterloaders for intraoperative radiation therapy.

    PubMed

    Gao, Song; Delclos, Marc E; Tomas, Lyvia C; Crane, Christopher H; Beddar, Sam

    2007-11-01

    Intraoperative radiation therapy (IORT) is a treatment option that directly irradiates a surgically exposed tumor or tumor bed while preventing radiation exposure of normal tissues. This article discusses the high-dose-rate intraoperative radiation therapy (HDR-IORT) technique by reviewing the roles of IORT team members, discussing needed equipment and supplies, describing quality assurance processes, explaining the HDR-IORT treatment delivery procedure, and reviewing the post-treatment phase. PMID:18050890

  11. [Intraoperative ultrasonography in the staging of pancreatic head neoplasms].

    PubMed

    Alberti, Antonino; Dattola, Pasquale; Littori, Francesca; Dattola, Arturo; Maccarone, Pietro; Basile, Maurizio

    2002-01-01

    Tumours of the head of the pancreas constitute the fourth most common cause of cancer deaths. These tumours are characterised by low survival rates (5% at 5 years) and low surgical resectability rates (20-25%). Liver metastases, lymph-node and vascular involvement, and peritoneal metastases are, in our opinion, exclusion criteria for curative surgical resection. The aim of the study was to evaluate the impact of intraoperative ultrasonography on the staging of such tumours. Over the period from 1990 to 2000 we introduced intraoperative ultrasonography in the staging of pancreatic cancer. We evaluated 51 patients who at preoperative staging had been regarded as candidates for surgical therapy consisting in a pancreaticoduodenectomy. All patients had been staged by preoperative abdominal ultrasound, ERCP, CT and MRI. Intraoperative ultrasound and colour-Doppler imaging (from 1997 on) revealed involvement of (i) the liver, (ii) the splenomesenteric vessels and (iii) the portal vein. Intraoperative ultrasonography yielded a diagnosis of occult liver metastases in 10 cases and signs of vascular involvement (absence of cleavage, partial and total thrombosis) in 12. One false-negative was registered. Intraoperative ultrasonography in our experience showed 98% sensitivity and specificity in the detection of vascular and lymph-node involvement. Its sensitivity in the detection of liver metastases was 100%. Intraoperative ultrasound is a procedure with a very high sensitivity in the operative staging of cancer of the head of the pancreas. PMID:11942011

  12. Thin-Profile Transducers for Intraoperative Hemostasis

    NASA Astrophysics Data System (ADS)

    Zderic, Vesna; Mera, Thomas; Vaezy, Shahram

    2005-03-01

    Our goal has been to develop thin-profile HIFU applicators for intraoperative hemostasis. The HIFU device consisted of a concave PZT element encased in a spoon-shaped aluminum housing with the diameter of 4 cm and thickness of 1 cm. The housing front surface had a thickness of 3/4 ultrasound wavelength in aluminum (0.92 mm) to provide acoustic matching. The device had a resonant frequency of 6.26 MHZ, and efficiency of 42%. The ultrasound field was observed using hydrophone field mapping and radiation force balance. The full-width half-maximum (FWHM) dimensions of the focal region were 0.6 mm and 2.2 mm in lateral and axial direction, respectively. The maximal intensity at the focus was 9,500 W/cm2 (in water). The device was tested using BSA-polyacrylamide gel phantom and rabbit kidney in vivo. HIFU application for 10 s produced lesions in the gel phantom (lesion width of 3 mm), and rabbit kidney in vivo (lesion width of 8 mm). A thin-profile HIFU applicator has advantages of high efficiency, simple design, and small dimensions.

  13. [Intraoperative radiotherapy in malignant bone tumors].

    PubMed

    Yamamuro, T; Kotoura, Y

    1993-06-01

    When a bone tumor is confirmed to be malignant by biopsy and has not expanded into the soft tissue, intraoperative radiation therapy (IORT) is indicated for most parts of the four extremities. The irradiation area is exposed through an extensive skin incision, and the soft tissues are opened and retracted away from the irradiation area, leaving a layer of normal tissue directly covering the tumor. The irradiation is performed with 12-26 MeV electron beams from a betatron at a dose of 50-100 Gy, depending on the radiosensitivity of each tumor. The multifocal bilateral irradiation method is the best for minimizing complications of the soft tissues. Since 1978, we have performed IORT in combination with chemotherapy in 41 cases of malignant bone tumors and experienced only five cases of tumor recurrence one in the irradiated area and four in the non-irradiated area. Joint function in the irradiated limb was excellent. However, due to the high incidence of pathological fracture after IORT in osteolytic tumors, the limb eventually had to be replaced by a prosthesis. After 1984 when cisplatinum was introduced to our chemotherapy protocol, the cumulative 5 year survival rate increased to 81%, with the irradiated lesion preserved in situ in osteoblastic tumors and replaced with a prosthesis in osteolytic tumors. PMID:8341560

  14. Perspectives in Intraoperative Diagnostics of Human Gliomas

    PubMed Central

    Tyurikova, O.; Dembitskaya, Y.; Yashin, K.; Mishchenko, M.; Vedunova, M.; Medyanik, I.; Kazantsev, V.

    2015-01-01

    Amongst large a variety of oncological diseases, malignant gliomas represent one of the most severe types of tumors. They are also the most common type of the brain tumors and account for over half of the astrocytic tumors. According to different sources, the average life expectancy of patients with various glioblastomas varies between 10 and 12 months and that of patients with anaplastic astrocytic tumors between 20 and 24 months. Therefore, studies of the physiology of transformed glial cells are critical for the development of treatment methods. Modern medical approaches offer complex procedures, including the microsurgical tumor removal, radiotherapy, and chemotherapy, supplemented with photodynamic therapy and immunotherapy. The most radical of them is surgical resection, which allows removing the largest part of the tumor, reduces the intracranial hypertension, and minimizes the degree of neurological deficit. However, complete removal of the tumor remains impossible. The main limitations are insufficient visualization of glioma boundaries, due to its infiltrative growth, and the necessity to preserve healthy tissue. This review is devoted to the description of advantages and disadvantages of modern intraoperative diagnostics of human gliomas and highlights potential perspectives for development of their treatment. PMID:26543495

  15. Intraoperative Radiotherapy for Locally Advanced Rectal Cancer

    PubMed Central

    Kim, Myung Se; Kim, Jae Hwang

    2010-01-01

    Purpose Although intraoperative radiotherapy (IORT) is known to be a method that can reduce local recurrence in locally advanced colorectal cancer, it is not widely used. The aim of this study was to report our experience with IORT for locally advanced rectal cancer. Methods From 1991 to 1994, nine patients with locally advanced rectal cancer received IORT. External beam radiotherapy was given postoperatively in five patients and preoperatively in three. Seven patients received chemotherapy. IORT was done with 6-MeV or 9-MeV electrons, and 12 Gy was irradiated at the tumor bed. The median follow-up period was 84 months (range, 15 to 208 months). Results The median age of patients was 51 years (range, 42 to 73 years). All patients had advanced clinical T-stage (cT3/4) cancer. The overall and the disease-free survival rates were 66.7% and 66.7% at 5 years, respectively. One patient developed a local recurrence near the anastomosis site, which was out of the IORT field. Four patients died before the last follow-up; three from distant metastasis and one from secondary primary cancer. Adverse effects related to IORT did not occur. Conclusion Although the number of patients was small in this study, IORT is thought to be safe and effective in reducing local recurrence in locally advanced rectal cancer. However, the role of IORT should be refined in the era of preoperative radio-chemotherapy followed by total mesorectal excision. PMID:21152229

  16. intraoperative radiation therapy part 2. Clinical results.

    PubMed

    Calvo, Felipe A; Meirino, Rosa M; Orecchia, Roberto

    2006-08-01

    Intraoperative radiation therapy (IORT) has been used for over 30 years in Asia, Europe and America as a supplementary activity in the treatment of cancer patients with promising results. Modern IORT is carried out with electron beams (IOERT) produced by a linear accelerator generally used for external beam irradiation (EBRT) or a specialized mobile electron accelerator. HDR brachytherapy (HDR-IORT) has also been applied on selected locations. Retrospective analysis of clinical experiences in cancer sites such as operable pancreatic tumour, locally advanced/recurrent rectal cancer, head and neck carcinomas, sarcomas and cervical cancer are consistent with local tumour control promotion compared to similar clinical experiences without IORT. New emerging indications such as the treatment of breast cancer are presented. The IORT component of the therapeutical approach allows intensification of the total radiation dose without additional exposure of healthy tissues and improves dose-deposit homogeneity and precision. Results of the application of IORT on selected disease sites are presented with an analysis on future possibilities. To improve the methodology, clinical trials are required with multivariate analysis including patient, tumour and treatment characteristics, prospective evaluation of early and late toxicity, patterns of tumour recurrence and overall patient outcome. PMID:16859922

  17. Perspectives in Intraoperative Diagnostics of Human Gliomas.

    PubMed

    Tyurikova, O; Dembitskaya, Y; Yashin, K; Mishchenko, M; Vedunova, M; Medyanik, I; Kazantsev, V

    2015-01-01

    Amongst large a variety of oncological diseases, malignant gliomas represent one of the most severe types of tumors. They are also the most common type of the brain tumors and account for over half of the astrocytic tumors. According to different sources, the average life expectancy of patients with various glioblastomas varies between 10 and 12 months and that of patients with anaplastic astrocytic tumors between 20 and 24 months. Therefore, studies of the physiology of transformed glial cells are critical for the development of treatment methods. Modern medical approaches offer complex procedures, including the microsurgical tumor removal, radiotherapy, and chemotherapy, supplemented with photodynamic therapy and immunotherapy. The most radical of them is surgical resection, which allows removing the largest part of the tumor, reduces the intracranial hypertension, and minimizes the degree of neurological deficit. However, complete removal of the tumor remains impossible. The main limitations are insufficient visualization of glioma boundaries, due to its infiltrative growth, and the necessity to preserve healthy tissue. This review is devoted to the description of advantages and disadvantages of modern intraoperative diagnostics of human gliomas and highlights potential perspectives for development of their treatment. PMID:26543495

  18. Intraoperative Electroretinograms before and after Core Vitrectomy

    PubMed Central

    Yagura, Kazuma; Shinoda, Kei; Matsumoto, Soiti; Terauchi, Gaku; Watanabe, Emiko; Matsumoto, Harue; Akiyama, Goichi; Mizota, Atsushi; Miyake, Yozo

    2016-01-01

    Purpose To evaluate retinal function by intraoperative electroretinograms (ERGs) before and after core vitrectomy. Design Retrospective consecutive case series. Method Full-field photopic ERGs were recorded prior to the beginning and just after core vitrectomy using a sterilized contact lens electrode in 20 eyes that underwent non-complicated vitreous surgery. A light-emitted diode was embedded into the contact lens, and a stimulus of 150 ms on and 350 ms off at 2 Hz was delivered. The amplitudes and latencies of the a-, b-, and d-waves, photopic negative response (PhNR), and oscillatory potentials (OPs) were analyzed. The intraocular temperature at the mid-vitreous was measured at the beginning and just after the surgery with a thermoprobe. Results The intraocular temperature was 33.2 ± 1.3°C before and 29.4 ± 1.7°C after the vitrectomy. The amplitudes of the PhNR and OPs were significantly smaller after surgery, and the latencies of all components were prolonged after the surgery. These changes were not significantly correlated with the changes of the temperature. Conclusion Retinal function is reduced just after core vitrectomy in conjunction with significant temperature reduction. The differences in the degree of alterations of each ERG component suggests different sensitivity of each type of retinal neuron. PMID:27010332

  19. Intraoperative neurophysiological monitoring in spinal surgery

    PubMed Central

    Park, Jong-Hwa; Hyun, Seung-Jae

    2015-01-01

    Recently, many surgeons have been using intraoperative neurophysiological monitoring (IOM) in spinal surgery to reduce the incidence of postoperative neurological complications, including level of the spinal cord, cauda equina and nerve root. Several established technologies are available and combined motor and somatosensory evoked potentials are considered mandatory for practical and successful IOM. Spinal cord evoked potentials are elicited compound potentials recorded over the spinal cord. Electrical stimulation is provoked on the dorsal spinal cord from an epidural electrode. Somatosensory evoked potentials assess the functional integrity of sensory pathways from the peripheral nerve through the dorsal column and to the sensory cortex. For identification of the physiological midline, the dorsal column mapping technique can be used. It is helpful for reducing the postoperative morbidity associated with dorsal column dysfunction when distortion of the normal spinal cord anatomy caused by an intramedullary cord lesion results in confusion in localizing the midline for the myelotomy. Motor evoked potentials (MEPs) consist of spinal, neurogenic and muscle MEPs. MEPs allow selective and specific assessment of the functional integrity of descending motor pathways, from the motor cortex to peripheral muscles. Spinal surgeons should understand the concept of the monitoring techniques and interpret monitoring records adequately to use IOM for the decision making during the surgery for safe surgery and a favorable surgical outcome. PMID:26380823

  20. [Intraoperative monitoring of cerebral blood-flow and condition of cerebral at open and endovascular interventions in carotid system].

    PubMed

    Kuntsevich, G I; Tanashian, M M; Skrylev, S I; Krotenkova, M V; Shchipakin, V L; Koshcheev, A Iu; Lagoda, O V; Gemdzhian, E G; Medvedev, R B; Kulikova, S N

    2011-01-01

    The aim of our research is to study hemodynamic and embolic situation during the carotid endarterectomy (CEA), carotid angioplastic and stenting (CAS), and to reveal the prognostic significance of the data provided by intraoperative monitoring of the brain blood flow in exposing acute ischemic lesions in brain. Intraoperative monitoring of blood flow in artery ophthalmic vas carried out with 60% of patients, in the middle cerebral artery-with 40% during the main stages of CEA, and with 64 patients in the middle cerebral artery during CAS. The comparison of the data of intraoperative monitoring of blood flow in middle cerebral artery with the result of brain diffusion-weighted magnetic resonance imaging (DW-MRI) 24 hours after the operation shows, that solid microembolic signals and vasospasm are prognostic signals (sensibility and specifics make up 95%) in the development of acute ischemic cerebral lesions. The monitoring of blood flow in artery ophthalmic is of the greatest diagnostic value in estimation of the hemodynamic situation, but it is of the lowest practical value in detecting microembolic signals. According to the data of the intraoperative blood flow monitoring in middle cerebral artery in group CEA the development of acute ischemic cerebral lesions were predicted with 11,1% of patients and the cause of postoperative stroke, developed by 2,9% of the patients, was specified. According to the result of DW-MRI, acute ischemic cerebral lesions were diagnosed with 21% of patients, that is, 18% of ischemic cerebral lesions were asymptomatic. In group CAS ischemic cerebral lesions were prognosed with 30% of patients, actually they were later detected with 40,6% of cases by means of DW-MRI. According to the data of intraoperative of blood flow monitoring the cause of the development of postoperative stroke was specified in 6,2% of cause; in 34,4% of cause the acute ischemic cerebral lesions were asymptomatic. PMID:22027520

  1. A light blanket for intraoperative photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Hu, Yida; Wang, Ken; Zhu, Timothy C.

    2009-06-01

    A novel light source - light blanket composed of a series of parallel cylindrical diffusing fibers (CDF) is designed to substitute the hand-held point source in the PDT treatment of the malignant pleural or intraperitoneal diseases. It achieves more uniform light delivery and less operation time in operating room. The preliminary experiment was performed for a 9cmx9cm light blanket composed of 8 9-cm CDFs. The linear diffusers were placed in parallel fingerlike pockets. The blanket is filled with 0.2 % intralipid scattering medium to improve the uniformity of light distribution. 0.3-mm aluminum foil is used to shield and reflect the light transmission. The full width of the profile of light distribution at half maximum along the perpendicular direction is 7.9cm and 8.1cm with no intralipid and with intralipid. The peak value of the light fluence rate profiles per input power is 11.7mW/cm2/W and 8.6mW/cm2/W respectively. The distribution of light field is scanned using the isotropic detector and the motorized platform. The average fluence rate per input power is 8.6 mW/cm2/W and the standard deviation is 1.6 mW/cm2/W for the scan in air, 7.4 mW/cm2/W and 1.1 mW/cm2/W for the scan with the intralipid layer. The average fluence rate per input power and the standard deviation are 20.0 mW/cm2/W and 2.6 mW/cm2/W respectively in the tissue mimic phantom test. The light blanket design produces a reasonably uniform field for effective light coverage and is flexible to confirm to anatomic structures in intraoperative PDT. It also has great potential value for superficial PDT treatment in clinical application.

  2. A light blanket for intraoperative photodynamic therapy

    PubMed Central

    Hu, Yida; Wang, Ken; Zhu, Timothy C.

    2015-01-01

    A novel light source - light blanket composed of a series of parallel cylindrical diffusing fibers (CDF) is designed to substitute the hand-held point source in the PDT treatment of the malignant pleural or intraperitoneal diseases. It achieves more uniform light delivery and less operation time in operating room. The preliminary experiment was performed for a 9cmx9cm light blanket composed of 8 9-cm CDFs. The linear diffusers were placed in parallel finger-like pockets. The blanket is filled with 0.2 % intralipid scattering medium to improve the uniformity of light distribution. 0.3-mm aluminum foil is used to shield and reflect the light transmission. The full width of the profile of light distribution at half maximum along the perpendicular direction is 7.9cm and 8.1cm with no intralipid and with intralipid. The peak value of the light fluence rate profiles per input power is 11.7mW/cm2/W and 8.6mW/cm2/W respectively. The distribution of light field is scanned using the isotropic detector and the motorized platform. The average fluence rate per input power is 8.6 mW/cm2/W and the standard deviation is 1.6 mW/cm2/W for the scan in air, 7.4 mW/cm2/W and 1.1 mW/cm2/W for the scan with the intralipid layer. The average fluence rate per input power and the standard deviation are 20.0 mW/cm2/W and 2.6 mW/cm2/W respectively in the tissue mimic phantom test. The light blanket design produces a reasonably uniform field for effective light coverage and is flexible to confirm to anatomic structures in intraoperative PDT. It also has great potential value for superficial PDT treatment in clinical application. PMID:25983369

  3. Our intraoperative boost radiotherapy experience and applications

    PubMed Central

    Günay, Semra; Alan, Ömür; Yalçın, Orhan; Türkmen, Aygen; Dizdar, Nihal

    2016-01-01

    Objective: To present our experience since November 2013, and case selection criteria for intraoperative boost radiotherapy (IObRT) that significantly reduces the local recurrence rate after breast conserving surgery in patients with breast cancer. Material and Methods: Patients who were suitable for IObRT were identified within the group of patients who were selected for breast conserving surgery at our breast council. A MOBETRON (mobile linear accelerator for IObRT) was used for IObRt during surgery. Results: Patients younger than 60 years old with <3 cm invasive ductal cancer in one focus (or two foci within 2 cm), with a histologic grade of 2–3, and a high possibility of local recurrence were admitted for IObRT application. Informed consent was obtained from all participants. Lumpectomy and sentinel lymph node biopsy was performed and advancement flaps were prepared according to the size and inclination of the conus following evaluation of tumor size and surgical margins by pathology. Distance to the thoracic wall was measured, and a radiation oncologist and radiation physicist calculated the required dose. Anesthesia was regulated with slower ventilation frequency, without causing hypoxia. The skin and incision edges were protected, the field was radiated (with 6 MeV electron beam of 10 Gy) and the incision was closed. In our cases, there were no major postoperative surgical or early radiotherapy related complications. Conclusion: The completion of another stage of local therapy with IObRT during surgery positively effects sequencing of other treatments like chemotherapy, hormonotherapy and radiotherapy, if required. IObRT increases disease free and overall survival, as well as quality of life in breast cancer patients. PMID:26985156

  4. Automated intraoperative calibration for prostate cancer brachytherapy

    SciTech Connect

    Kuiran Chen, Thomas; Heffter, Tamas; Lasso, Andras; Pinter, Csaba; Abolmaesumi, Purang; Burdette, E. Clif; Fichtinger, Gabor

    2011-11-15

    Purpose: Prostate cancer brachytherapy relies on an accurate spatial registration between the implant needles and the TRUS image, called ''calibration''. The authors propose a new device and a fast, automatic method to calibrate the brachytherapy system in the operating room, with instant error feedback. Methods: A device was CAD-designed and precision-engineered, which mechanically couples a calibration phantom with an exact replica of the standard brachytherapy template. From real-time TRUS images acquired from the calibration device and processed by the calibration system, the coordinate transformation between the brachytherapy template and the TRUS images was computed automatically. The system instantly generated a report of the target reconstruction accuracy based on the current calibration outcome. Results: Four types of validation tests were conducted. First, 50 independent, real-time calibration trials yielded an average of 0.57 {+-} 0.13 mm line reconstruction error (LRE) relative to ground truth. Second, the averaged LRE was 0.37 {+-} 0.25 mm relative to ground truth in tests with six different commercial TRUS scanners operating at similar imaging settings. Furthermore, testing with five different commercial stepper systems yielded an average of 0.29 {+-} 0.16 mm LRE relative to ground truth. Finally, the system achieved an average of 0.56 {+-} 0.27 mm target registration error (TRE) relative to ground truth in needle insertion tests through the template in a water tank. Conclusions: The proposed automatic, intraoperative calibration system for prostate cancer brachytherapy has achieved high accuracy, precision, and robustness.

  5. Intraoperative cell salvage in revision hip surgery

    PubMed Central

    Herd, J.M.; Joseph, J.J.; McGarvey, M.; Tsimbouri, P.; Bennett, A.; Meek, R.M.D.; Morrison, A.

    2014-01-01

    Allogenic blood is a finite resource, with associated risks. Previous studies show intraoperative cell salvage (ICS) can reduce allogenic transfusion rates in orthopaedic surgery. However, there are concerns regarding efficacy and cost-effectiveness of ICS. This study was carried out to review ICS use in revision hip arthroplasty. All patients who underwent ICS and re-infusion between 2008 and 2010 in the Southern General Hospital (SGH) were audited. The fall in haemoglobin (Hb), volume of blood re-infused and postoperative allogenic transfusion rates were recorded. This group was compared to a similar SGH cohort who underwent surgery by the same surgeons between 2006 and 2008, and a pre-2005 control group where no ICS was used. The proportion of patients receiving a postoperative allogenic transfusion fell by 55% in the 2008–2010 ICS cohort compared with the control, and by 40% compared with the previous ICS group. In both instances, there was a statistically significant (p < 0.001) reduction in mean units transfused per patient; in the 2008–2010 ICS cohort, a mean of 0.8 units was used per patient, while 1.4 were used in the 2006–2008 cohort. 3.5 units were used in the control group. There was no statistically significant difference in age or preoperative Hb between the groups, or in length of hospital stay. In this study, ICS has been shown to be effective in reducing rates and volume of postoperative allogenic transfusion in patients undergoing revision hip surgery at the SGH. However, further work is needed to establish the effect of changing anaesthetic technique on postoperative allogenic transfusion rates. PMID:25568779

  6. Intraoperative Patient Selection for Tubeless Percutaneous Nephrolithotomy

    PubMed Central

    Lee, Joo Yong; Kim, Kyu Hyun; Kim, Man Deuk; Chung, Doo Yong; Cho, Kang Su

    2014-01-01

    This study was conducted to report our experience of intraoperative patient selection for tubeless percutaneous nephrolithotomy (PCNL) based on a tentative decision-making algorithm. Thirty-four consecutive patients who were scheduled to undergo tubeless PCNL were included and medical records were obtained from a prospectively maintained database for these patients. After completion of PCNL, the nephrostomy site was observed with a safety guidewire in place. If there was no significant bleeding through the tract, tubeless PCNL was performed, and in cases with significant bleeding or other complications, nephrostomy catheter insertion was performed as usual. In 29 cases (85.3%), tubeless PCNL was performed according to our decision-making protocol. Mean stone size was 7.33 9.35 cm2. Mean hospital stay was 2.61 1.01 days. The difference between preoperative and postoperative hemoglobin was 0.68 1.22 g/dL (p > 0.05). Visual analog pain scale scores immediately post-operation, on postoperative day one and on the day of discharge were 4.62 1.80, 3.25 1.68 (postoperative day one vs. operative day; p = 0.001), and 1.87 0.83 (the day of discharge vs. operative day; p = 0.001), respectively. The success rate with insignificant remnant stones was 85.2% and complete stone-free rate was 76.5%. In conclusion, tubeless PCNL was performed successfully with low complication rate and reduced pain score through our decision-making algorithm. PMID:25216439

  7. Global warming elucidated

    SciTech Connect

    Shen, S.

    1995-03-01

    The meaning of global warming and its relevance to everyday life is explained. Simple thermodynamics is used to predict an oscillatory nature of the change in climate due to global warming. Global warming causes extreme events and bad weather in the near term. In the long term it may cause the earth to transition to another equilibrium state through many oscillation in climatic patterns. The magnitudes of these oscillations could easily exceed the difference between the end points. The author further explains why many no longer fully understands the nature and magnitudes of common phenomena such as storms and wind speeds because of these oscillations, and the absorptive properties of clouds. The author links the increase in duration of the El Nino to global warming, and further predicts public health risks as the earth transitions to another equilibrium state in its young history.

  8. Reconciling Warming Trends

    NASA Technical Reports Server (NTRS)

    Schmidt, Gavin A.; Shindell, Drew T.; Tsigaridis, Konstantinos

    2014-01-01

    Climate models projected stronger warming over the past 15 years than has been seen in observations. Conspiring factors of errors in volcanic and solar inputs, representations of aerosols, and El NiNo evolution, may explain most of the discrepancy.

  9. Warm and Cool Dinosaurs.

    ERIC Educational Resources Information Center

    Mannlein, Sally

    2001-01-01

    Presents an art activity in which first grade students draw dinosaurs in order to learn about the concept of warm and cool colors. Explains how the activity also helped the students learn about the concept of distance when drawing. (CMK)

  10. Warm Hands and Feet

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Comfort Products, Inc. was responsible for the cold weather glove and thermal boots, adapted from a spacesuit design that kept astronauts warm or cool in the temperature extremes of the Apollo Moon Mission. Gloves and boots are thermally heated. Batteries are worn inside wrist of glove or sealed in sole of skiboot and are rechargeable hundreds of times. They operate flexible resistance circuit which is turned on periodically when wearer wants to be warm.

  11. Intraoperative probe-directed immunodetection using a monoclonal antibody

    SciTech Connect

    O'Dwyer, P.J.; Mojzisik, C.M.; Hinkle, G.H.; Rousseau, M.; Olsen, J.; Tuttle, S.E.; Barth, R.F.; Thurston, M.O.; McCabe, D.P.; Farrar, W.B.

    1986-12-01

    To assess monoclonal antibody (MAb) 17-1A and its F(ab')2 fragment in intraoperative radioimmunodetection and to evaluate further the clinical usefulness of a hand-held gamma-detecting probe (GDP), we injected radiolabeled monoclonal antibody 17-1A three to six days preoperatively or its F(ab')2 fragment two to three days preoperatively into 18 patients with colorectal cancer. Intraoperative GDP counts with tumor-tissue ratios of 1.5:1 or greater were obtained from 15 (75%) of 20 tumor sites, with ratios averaging 2.3:1 for fragments and 3.4:1 for whole antibody. The GDP counts contributed to intraoperative decision making in three patients, either by localization of tumor not identified by inspection or palpation or by mapping margins of resection with histologic confirmation of a local/regional recurrence. These preliminary data demonstrate that probe-directed, intraoperative radioimmunodetection can assist the surgeon in detecting subclinical tumor deposits and thus better evaluate the extent of primary or recurrent colorectal cancers intraoperatively.

  12. Intraoperative Contrast Enhanced Ultrasound Evaluates the Grade of Glioma

    PubMed Central

    Cheng, Ling-Gang; He, Wen; Zhang, Hong-Xia; Song, Qian; Ning, Bin; Li, Hui-Zhan; He, Yan; Lin, Song

    2016-01-01

    Objective. The aim of our study was to investigate the value of intraoperative contrast enhanced ultrasound (CEUS) for evaluating the grade of glioma and the correlation between microvessel density (MVD) and vascular endothelial growth factor (VEGF). Methods. We performed intraoperative conventional ultrasound (CUS) and CEUS on 88 patients with gliomas. All of the patients have undergone surgery and obtained the results of pathology. All patients have undergone intraoperative CUS and CEUS to compare the characteristics of different grade gliomas and the results of CUS and CEUS were compared with pathological results. Results. The time to start (TTS) and time to peak (TTP) of low grade glioma (LGG) were similar to those of edema and normal brain surrounding glioma. The enhanced extent of LGG was higher than that of the normal brain and edema. The TTS and TTP of high grade glioma were earlier than those of the edema and normal brain surrounding glioma. The enhancement of HGG was higher than that of LGG. The absolute peak intensity (API) was correlated with MVD and VEGF. Conclusion. Intraoperative CEUS could help in determining boundary of peritumoral brain edema of glioma. Intraoperative CEUS parameters in cerebral gliomas could indirectly reflect the information of MVD and VEGF. PMID:27069921

  13. Preoperative and intraoperative localisation of gastrointestinal bleeding of obscure origin.

    PubMed Central

    Lau, W Y; Fan, S T; Wong, S H; Wong, K P; Poon, G P; Chu, K W; Yip, W C; Wong, K K

    1987-01-01

    In the past six years, 37 patients with gastrointestinal bleeding of obscure origin had their bleeding sites localised preoperatively or intraoperatively. Preoperative investigations followed a regime consisting of endoscopy, barium meal and follow through, small bowel enema, 99mTc pertechnetate scan, 99mTc-labelled red blood cell scan and selective coeliac and mesenteric angiography. Bleeding lesions were localised preoperatively in 36 patients. In one patient, diagnostic laparotomy had to be carried out immediately before any investigation because the bleeding was severe. At operation, angiosarcoma of ileum was found. Unless preoperative investigations showed the lesions to be in anatomically fixed organs like the duodenum or colon, the lesions had still to be found at operation. Palpation and transillumination detected the lesion intraoperatively in 21 patients while only some lesions were found in three patients with multiple lesions. Sigmoidoscopy through enterotomies was required in one patient. Intraoperative enteroscopy was done for small lesions not found grossly at operation in nine patients, to detect additional lesions in three patients or to rule out suspicious lesion shown on preoperative tests in one patient. In another patient with diffuse lymphoma of small bowel with bleeding from only a small segment of jejunum, injection of methylene blue intraoperatively through a previously placed angiographic catheter stained the bleeding segment of jejunum blue. This segment was identified easily and resected. These preoperative and intraoperative localisation procedures were simple and effective and we recommend them to be used more freely. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:3498667

  14. Integrated assessment of global warming

    SciTech Connect

    Ott, K.O.

    1996-12-31

    The anomalies of sea surface temperatures, which show a warming trend since the 1850s through the decade 1960/70 of {Delta}SST {approximately} 0.3 C, are complemented by changes of the ground surface temperature ({Delta}GST). The global surface temperature change, based on these data, allows an integrated assessment of the associated increase in black-body irradiance and a comparison with the enhanced greenhouse-gas back-scattering. Information on the GST history is obtained from unfolding analyses of underground temperature distributions measured in 90 boreholes in Alaskan permafrost and Canadian bedrock. These analyses show GST increases ({Delta}GST) since the 19th century through 1960/70 of 3 C on average, with standard deviations of +1.8 C and {minus}0.9 C on the high and low end respectively. The onset of the warming trend, which is uncertain in the GST data, is timed more accurately by detailed length records of large valley glaciers in the US and the Alps. Evaluation of the heat capacities and heat transfer indicates that the temperature response to an increase in radiative forcing must be much larger on land than on the sea. Conversely, the observed large ratio of {Delta}GST and {Delta}SST can only be explained by increased radiative forcing. From 1960/70 through the warmest decade on record, 1980/90, global {Delta}SST and {Delta}SAT have further increased to 0.6 C and 0.8 C respectively, But, the most recent GST data are not accurate enough to extend the comparison through 1990. Calculation of the increase of radiative forcing from back-scattering of greenhouse gases for 1850 to 1970 yields 1.3 W/cm{sup 2}. The increase in black-body irradiance from 3.6 C warming on land and 0.3 C on sea provides the required balance. The warming on land of 3.6 C is larger than the average value of 3.0 C, but well within the observed range.

  15. Intraoperative autotransfusion: equipment, protocols, and guidelines.

    PubMed

    Raines, J; Buth, J; Brewster, D C; Darling, R C

    1976-08-01

    Blood obtained by intraoperative autotransfusion is: 1) readily available 2) sterile 3) compatible 4) normothermic 5) inexpensive and may be infused rapidly for volume support. We have made extensive modifications to commercially available equipment in order to provide a safe, effective IAT. The effects of IAT in our series of 85 patients are outlined below. Red Cell Mass is reduced after IAT because of irretrievable blood loss and hemolysis, and may be controlled by homologous transfusion when necessary. Red Cell Survival is normal after IAT. Hemolysis. Plasma free hemoglobin is consistently elevated after IAT, but clears within 24 hours. Platelets are normal for patients autotransfused less than 3,500 ml; micropore filters should not be used in cases where greater than 3,500 ml blood is expected to be reinfused; in cases where greater than 3,500 ml is reinfused, 10 units of platelets are recommended for every 3,000 ml of blood reinfused; IAT does effect platelets function; however, platelets circulating within the patient function normally. Coagulation. We use local ACD to eliminate extracorporeal surface clotting. Even with massive IAT we have never demonstrated any clinical or laboratory evidence of intravascular coagulopathy. "Dilutional coagulopathy" may be procuced when greater than 5,000 ml are reinfused, and may be controlled with fresh frozen plasma and platelet concentrates. Bilirubin levels were normal after IAT despite gross hemoglobinuria. Fat emboli were not noted after IAT. Air emboli must be a concern in IAT; HOWEVER, PROPER OPERATION AND EQUIPMENT MODIFICATION MAY ELIMINATE EMBOLI. Renal Failure was not noted after IAT. Alveolar-arterial Oxygen Difference and Blood Gases were normal after IAT. We feel IAT is not necessary if a blood loss less than 1,000 ml is expected. Also, if greater than 3,500 ml is expected additional backup (i.e. homologous transfusions, platelets, fresh frozen plasma) may be required. As banked donor blood reserves become more limited, IAT may become a routine part of general surgical procedures. PMID:957457

  16. Indocyanine green for intraoperative localization of ureter.

    PubMed

    Siddighi, Sam; Yune, Junchan Joshua; Hardesty, Jeffrey

    2014-10-01

    Intraurethral injection of indocyanine green (ICG; Akorn, Lake Forest, IL) and visualization under near-infrared (NIR) light allows for real-time delineation of the ureter. This technology can be helpful to prevent iatrogenic ureteral injury during pelvic surgery. Patients were scheduled to undergo robot-assisted laparoscopic sacrocolpopexy. Before the robotic surgery started, the tip of a 6-F ureteral catheter was inserted into the ureteral orifice. Twenty-five milligrams of ICG was dissolved in 10-mL of sterile water and injected through the open catheter. The same procedure was repeated on the opposite side. The ICG reversibly stained the inside lining of the ureter by binding to proteins on urothelial layer. During the course of robotic surgery, the NIR laser on the da Vinci Si surgical robot (Intuitive Surgical, Inc, Sunnyvale, CA) was used to excite ICG molecules, and infrared emission was captured by the da Vinci filtered lens system and electronically converted to green color. Thus, the ureter fluoresced green, which allowed its definitive identification throughout the entire case. In all cases of >10 patients, we were able to visualize bilateral ureters with this technology, even though there was some variation in brightness that depended on the depth of the ureter from the peritoneal surface. For example, in a morbidly obese patient, the ureters were not as bright green. There were no intraoperative or postoperative adverse effects attributable to ICG administration for up to 2 months of observation. In our experience, this novel method of intraurethral ICG injection was helpful to identify the entire course of ureter and allowed a safe approach to tissues that were adjacent to the urinary tract. The advantage of our technique is that it requires the insertion of just the tip of ureteral catheter. Despite our limited cohort of patients, our findings are consistent with previous reports of the excellent safety profile of intravenous and intrabiliary ICG. Intraurethral injection of ICG and visualization under NIR light allows for real-time delineation of the ureter. This technology can be helpful to prevent iatrogenic ureteral injury during pelvic surgery. PMID:24835212

  17. Warm up to the idea: Global warming is here

    SciTech Connect

    Lynch, C.F.

    1996-07-01

    This article summarizes recent information about global warming as well as the history of greenhouse gas emissions which have lead to more and more evidence of global warming. The primary source detailed is the second major study report on global warming by the Intergovernmental Panel on climate change. Along with comments about the environmental effects of global warming such as coastline submersion, the economic, social and political aspects of alleviating greenhouse emissions and the threat of global warming are discussed.

  18. Long range global warming

    SciTech Connect

    Rolle, K.C.; Pulkrabek, W.W.; Fiedler, R.A.

    1995-12-31

    This paper explores one of the causes of global warming that is often overlooked, the direct heating of the environment by engineering systems. Most research and studies of global warming concentrate on the modification that is occurring to atmospheric air as a result of pollution gases being added by various systems; i.e., refrigerants, nitrogen oxides, ozone, hydrocarbons, halon, and others. This modification affects the thermal radiation balance between earth, sun and space, resulting in a decrease of radiation outflow and a slow rise in the earth`s steady state temperature. For this reason the solution to the problem is perceived as one of cleaning up the processes and effluents that are discharged into the environment. In this paper arguments are presented that suggest, that there is a far more serious cause for global warming that will manifest itself in the next two or three centuries; direct heating from the exponential growth of energy usage by humankind. Because this is a minor contributor to the global warming problem at present, it is overlooked or ignored. Energy use from the combustion of fuels and from the output of nuclear reactions eventually is manifest as warming of the surroundings. Thus, as energy is used at an ever increasing rate the consequent global warming also increases at an ever increasing rate. Eventually this rate will become equal to a few percent of solar radiation. When this happens the earth`s temperature will have risen by several degrees with catastrophic results. The trends in world energy use are reviewed and some mathematical models are presented to suggest future scenarios. These models can be used to predict when the global warming problem will become undeniably apparent, when it will become critical, and when it will become catastrophic.

  19. Global warming on trial

    SciTech Connect

    Broeker, W.S.

    1992-04-01

    Jim Hansen, a climatologist at NASA's Goddard Space Institute, is convinced that the earth's temperature is rising and places the blame on the buildup of greenhouse gases in the atmosphere. Unconvinced, John Sununu, former White House chief of staff, doubts that the warming will be great enough to produce serious threat and fears that measures to reduce the emissions would throw a wrench into the gears that drive the Unites States' troubled economy. During his three years at the White House, Sununu's view prevailed, and although his role in the debate has diminished, others continue to cast doubt on the reality of global warming. A new lobbying group called the Climate Council has been created to do just this. Burning fossil fuels is not the only problem; a fifth of emissions of carbon dioxide now come from clearing and burning forests. Scientists are also tracking a host of other greenhouse gases that emanate from a variety of human activities; the warming effect of methane, chlorofluorocarbons and nitrous oxide combined equals that of carbon dioxide. Although the current warming from these gases may be difficult to detect against the background noise of natural climate variation, most climatologists are certain that as the gases continue to accumulate, increases in the earth's temperature will become evident even to skeptics. If the reality of global warming were put on trial, each side would have trouble making its case. Jim Hansen's side could not prove beyond a reasonable doubt that carbon dioxide and other greenhouse gases have warmed the planet. But neither could John Sununu's side prove beyond a reasonable doubt that the warming expected from greenhouse gases has not occurred. To see why each side would have difficulty proving its case, this article reviews the arguments that might be presented in such a hearing.

  20. [Intracoronary air embolism detected during intraoperative transesophageal echocardiography].

    PubMed

    Cabrera Schulmeyer, M C; Santelices Cuevas, E; Vega Sepúlveda, R; Allamand, F; De la Maza, J C

    2005-01-01

    A 39-year-old hypertensive man with severe aortic stenosis underwent aortic valve replacement monitored by intraoperative transesophageal echocardiography. Upon weaning the patient off extracorporeal circulation, hemodynamics became severely compromised, with hypotension, tachycardia, and elevated precordial electrocardiographic tracings. The echocardiographic images were instrumental during the episode to demonstrate that the anterior wall presented hypokinesis consistent with ischemia in the region but that there were also images of hyperrefringence highly suggestive of intracoronary air embolism. Intraoperative transesophageal echocardiography allowed us to diagnose the real cause of the ischemic event and rule out an atheromatous plaque as the source. Perfusion pressure was increased to treat the air embolism. The echocardiographic image demonstrated success, specifically restoration of left ventricular regional contractility. This experience revealed the usefulness of transesophageal echocardiography in intraoperative monitoring to diagnose ischemia, assess the cause, and guide treatment. PMID:16038178

  1. The Use of Optical Coherence Tomography in Intraoperative Ophthalmic Imaging

    PubMed Central

    Hahn, Paul; Migacz, Justin; O’Connell, Rachelle; Maldonado, Ramiro S.; Izatt, Joseph A.; Toth, Cynthia A.

    2012-01-01

    Optical coherence tomography (OCT) has transformed diagnostic ophthalmic imaging but until recently has been limited to the clinic setting. The development of spectral-domain OCT (SD-OCT), with its improved speed and resolution, along with the development of a handheld OCT scanner, enabled portable imaging of patients unable to sit in a conventional tabletop scanner. This handheld SD-OCT unit has proven useful in examinations under anesthesia and, more recently, in intraoperative imaging of preoperative and postoperative manipulations. Recently, several groups have pioneered the development of novel OCT modalities, such as microscope-mounted OCT systems. Although still immature, the development of these systems is directed toward real-time imaging of surgical maneuvers in the intraoperative setting. This article reviews intraoperative imaging of the posterior and anterior segment using the handheld SD-OCT and recent advances toward real-time microscope-mounted intrasurgical imaging. PMID:21790116

  2. Intraoperative Ultrasound-Fluoroscopy Fusion can Enhance Prostate Brachytherapy Quality

    SciTech Connect

    Orio, Peter F.; Tutar, Ismail B.; Narayanan, Sreeram; Arthurs, Sandra; Cho, Paul S.; Kim, Yongmin; Merrick, Gregory; Wallner, Kent E.

    2007-09-01

    Purpose: To evaluate a transrectal ultrasound (TRUS)-fluoroscopy fusion-based intraoperative dosimetry system. Method and Materials: Twenty-five patients were treated for prostate cancer with Pd-103 implantation. After the execution of the treatment plan, two sets of TRUS images were collected using the longitudinal and axial transducers of a biplanar probe. Then, three fluoroscopic images were acquired at 0, -15 and +15{sup o}. The three-dimensional locations of all implanted seeds were reconstructed from fluoroscopic images. A subset of the implanted seeds was manually identified in TRUS images and used as fiducial markers to perform TRUS-fluoroscopy fusion. To improve the implant quality, additional seeds were placed if adverse isodose patterns were identified during visual inspection. If additional seeds were placed, intraoperative dosimetry was repeated. Day 0 computed tomography-based dosimetry was compared with final intraoperative dosimetry to validate dosimetry achieved in the implant suite. Results: An average of additional 4.0 seeds was implanted in 16 patients after initial intraoperative dose evaluation. Based on TRUS-fluoroscopy fusion-based dosimetry, the V100 improved from 86% to 93% (p = 0.005), whereas D90 increased from 94% to 109% (p = 0.011) with the guided additional seed implantation. No statistical difference was observed in V200 and V300 values. V100 and D90 values were 95 {+-} 4% and 120 {+-} 24%, respectively, based on the final intraoperative dosimetry evaluation, compared with 95 {+-} 4% and 122 {+-} 24%, respectively, based on Day 0 computed tomography-based dosimetry. Conclusions: Implantation of extra seeds based on TRUS-fluoroscopy fusion-based intraoperative dosimetry can improve the final V100 and D90 values with minimal increase in V200 and V300 values.

  3. ENSO and greenhouse warming

    NASA Astrophysics Data System (ADS)

    Cai, Wenju; Santoso, Agus; Wang, Guojian; Yeh, Sang-Wook; An, Soon-Il; Cobb, Kim M.; Collins, Mat; Guilyardi, Eric; Jin, Fei-Fei; Kug, Jong-Seong; Lengaigne, Matthieu; McPhaden, Michael J.; Takahashi, Ken; Timmermann, Axel; Vecchi, Gabriel; Watanabe, Masahiro; Wu, Lixin

    2015-09-01

    The El Nio/Southern Oscillation (ENSO) is the dominant climate phenomenon affecting extreme weather conditions worldwide. Its response to greenhouse warming has challenged scientists for decades, despite model agreement on projected changes in mean state. Recent studies have provided new insights into the elusive links between changes in ENSO and in the mean state of the Pacific climate. The projected slow-down in Walker circulation is expected to weaken equatorial Pacific Ocean currents, boosting the occurrences of eastward-propagating warm surface anomalies that characterize observed extreme El Nio events. Accelerated equatorial Pacific warming, particularly in the east, is expected to induce extreme rainfall in the eastern equatorial Pacific and extreme equatorward swings of the Pacific convergence zones, both of which are features of extreme El Nio. The frequency of extreme La Nia is also expected to increase in response to more extreme El Nios, an accelerated maritime continent warming and surface-intensified ocean warming. ENSO-related catastrophic weather events are thus likely to occur more frequently with unabated greenhouse-gas emissions. But model biases and recent observed strengthening of the Walker circulation highlight the need for further testing as new models, observations and insights become available.

  4. Intraoperative wide bore nasogastric tube knotting: A rare incidence

    PubMed Central

    Lamba, Sangeeta; Sethi, Surendra K.; Khare, Arvind; Saini, Sudheendra

    2016-01-01

    Nasogastric tubes are commonly used in anesthetic practice for gastric decompression in surgical patients intraoperatively. The indications for its use are associated with a number of potential complications. Knotting of small-bore nasogastric tubes is usually common both during insertion and removal as compared to wide bore nasogastric tubes. Knotting of wide bore nasogastric tube is a rare complication and if occurs usually seen in long standing cases. We hereby report a case of incidental knotting of wide bore nasogastric tube that occurred intraoperatively. PMID:26957700

  5. Minimally Invasive Spinal Surgery with Intraoperative Image-Guided Navigation

    PubMed Central

    Kim, Terrence T.; Johnson, J. Patrick; Pashman, Robert; Drazin, Doniel

    2016-01-01

    We present our perioperative minimally invasive spine surgery technique using intraoperative computed tomography image-guided navigation for the treatment of various lumbar spine pathologies. We present an illustrative case of a patient undergoing minimally invasive percutaneous posterior spinal fusion assisted by the O-arm system with navigation. We discuss the literature and the advantages of the technique over fluoroscopic imaging methods: lower occupational radiation exposure for operative room personnel, reduced need for postoperative imaging, and decreased revision rates. Most importantly, we demonstrate that use of intraoperative cone beam CT image-guided navigation has been reported to increase accuracy. PMID:27213152

  6. Intraoperative wide bore nasogastric tube knotting: A rare incidence.

    PubMed

    Lamba, Sangeeta; Sethi, Surendra K; Khare, Arvind; Saini, Sudheendra

    2016-01-01

    Nasogastric tubes are commonly used in anesthetic practice for gastric decompression in surgical patients intraoperatively. The indications for its use are associated with a number of potential complications. Knotting of small-bore nasogastric tubes is usually common both during insertion and removal as compared to wide bore nasogastric tubes. Knotting of wide bore nasogastric tube is a rare complication and if occurs usually seen in long standing cases. We hereby report a case of incidental knotting of wide bore nasogastric tube that occurred intraoperatively. PMID:26957700

  7. Intraoperative neurophysiology in deep brain surgery for psychogenic dystonia

    PubMed Central

    Ramos, Vesper Fe Marie L; Pillai, Ajay S; Lungu, Codrin; Ostrem, Jill; Starr, Philip; Hallett, Mark

    2015-01-01

    Psychogenic dystonia is a challenging entity to diagnose and treat because little is known about its pathophysiology. We describe two cases of psychogenic dystonia who underwent deep brain stimulation when thought to have organic dystonia. The intraoperative microelectrode recordings in globus pallidus internus were retrospectively compared with those of five patients with known DYT1 dystonia using spontaneous discharge parameters of rate and bursting, as well as movement-related discharges. Our data suggest that simple intraoperative neurophysiology measures in single subjects do not differentiate psychogenic dystonia from DYT1 dystonia. PMID:26125045

  8. Model predicts global warming

    NASA Astrophysics Data System (ADS)

    Wainger, Lisa A.

    Global greenhouse warming will be clearly identifiable by the 1990s, according to eight scientists who have been studying climate changes using computer models. Researchers at NASA's Goddard Space Flight Center, Goddard Institute for Space Studies, New York, and the Massachusetts Institute of Technology, Cambridge, say that by the 2010s, most of the globe will be experiencing “substantial” warming. The level of warming will depend on amounts of trace gases, or greenhouse gases, in the atmosphere.Predictions for the next 70 years are based on computer simulations of Earth's climate. In three runs of the model, James Hansen and his colleagues looked at the effects of changing amounts of atmospheric gases with time.

  9. Surgery for intramedullary spinal cord tumors: the role of intraoperative (neurophysiological) monitoring.

    PubMed

    Sala, Francesco; Bricolo, Albino; Faccioli, Franco; Lanteri, Paola; Gerosa, Massimo

    2007-11-01

    In spite of advancements in neuro-imaging and microsurgical techniques, surgery for intramedullary spinal cord tumors (ISCT) remains a challenging task. The rationale for using intraoperative neurophysiological monitoring (IOM) is in keeping with the goal of maximizing tumor resection and minimizing neurological morbidity. For many years, before the advent of motor evoked potentials (MEPs), only somatosensory evoked potentials (SEPs) were monitored. However, SEPs are not aimed to reflect the functional integrity of motor pathways and, nowadays, the combined used of SEPs and MEPs in ISCT surgery is almost mandatory because of the possibility to selectively injury either the somatosensory or the motor pathways. This paper is aimed to review our perspective in the field of IOM during ISCT surgery and to discuss it in the light of other intraoperative neurophysiologic strategies that have recently appeared in the literature with regards to ISCT surgery. Besides standard cortical SEP monitoring after peripheral stimulation, both muscle (mMEPs) and epidural MEPs (D-wave) are monitored after transcranial electrical stimulation (TES). Given the dorsal approach to the spinal cord, SEPs must be monitored continuously during the incision of the dorsal midline. When the surgeon starts to work on the cleavage plane between tumor and spinal cord, attention must be paid to MEPs. During tumor removal, we alternatively monitor D-wave and mMEPs, sustaining the stimulation during the most critical steps of the procedure. D-waves, obtained through a single pulse TES technique, allow a semi-quantitative assessment of the functional integrity of the cortico-spinal tracts and represent the strongest predictor of motor outcome. Whenever evoked potentials deteriorate, temporarily stop surgery, warm saline irrigation and improved blood perfusion have proved useful for promoting recovery, Most of intraoperative neurophysiological derangements are reversible and therefore IOM is able to prevent more than merely predict neurological injury. In our opinion combining mMEPs and D-wave monitoring, when available, is the gold standard for ISCT surgery because it supports a more aggressive surgery in the attempt to achieve a complete tumor removal. If quantitative (threshold or waveform dependent) mMEPs criteria only are used to stop surgery, this likely impacts unfavorably on the rate of tumor removal. PMID:17653776

  10. Volumetric Intraoperative Brain Deformation Compensation: Model Development and Phantom Validation

    PubMed Central

    DeLorenzo, Christine; Papademetris, Xenophon; Staib, Lawrence H.; Vives, Kenneth P.; Spencer, Dennis D.; Duncan, James S.

    2012-01-01

    During neurosurgery, nonrigid brain deformation may affect the reliability of tissue localization based on preoperative images. To provide accurate surgical guidance in these cases, preoperative images must be updated to reflect the intraoperative brain. This can be accomplished by warping these preoperative images using a biomechanical model. Due to the possible complexity of this deformation, intraoperative information is often required to guide the model solution. In this paper, a linear elastic model of the brain is developed to infer volumetric brain deformation associated with measured intraoperative cortical surface displacement. The developed model relies on known material properties of brain tissue, and does not require further knowledge about intraoperative conditions. To provide an initial estimation of volumetric model accuracy, as well as determine the model’s sensitivity to the specified material parameters and surface displacements, a realistic brain phantom was developed. Phantom results indicate that the linear elastic model significantly reduced localization error due to brain shift, from >16 mm to under 5 mm, on average. In addition, though in vivo quantitative validation is necessary, preliminary application of this approach to images acquired during neocortical epilepsy cases confirms the feasibility of applying the developed model to in vivo data. PMID:22562728

  11. Capturing intraoperative deformations: research experience at Brigham and Women's Hospital.

    PubMed

    Warfield, Simon K; Haker, Steven J; Talos, Ion-Florin; Kemper, Corey A; Weisenfeld, Neil; Mewes, Andrea U J; Goldberg-Zimring, Daniel; Zou, Kelly H; Westin, Carl-Fredrik; Wells, William M; Tempany, Clare M C; Golby, Alexandra; Black, Peter M; Jolesz, Ferenc A; Kikinis, Ron

    2005-04-01

    During neurosurgical procedures the objective of the neurosurgeon is to achieve the resection of as much diseased tissue as possible while achieving the preservation of healthy brain tissue. The restricted capacity of the conventional operating room to enable the surgeon to visualize critical healthy brain structures and tumor margin has lead, over the past decade, to the development of sophisticated intraoperative imaging techniques to enhance visualization. However, both rigid motion due to patient placement and nonrigid deformations occurring as a consequence of the surgical intervention disrupt the correspondence between preoperative data used to plan surgery and the intraoperative configuration of the patient's brain. Similar challenges are faced in other interventional therapies, such as in cryoablation of the liver, or biopsy of the prostate. We have developed algorithms to model the motion of key anatomical structures and system implementations that enable us to estimate the deformation of the critical anatomy from sequences of volumetric images and to prepare updated fused visualizations of preoperative and intraoperative images at a rate compatible with surgical decision making. This paper reviews the experience at Brigham and Women's Hospital through the process of developing and applying novel algorithms for capturing intraoperative deformations in support of image guided therapy. PMID:15721230

  12. Avoiding and Managing Intraoperative Complications During Cervical Spine Surgery.

    PubMed

    Bible, Jesse E; Rihn, Jeffrey A; Lim, Moe R; Brodke, Darrel S; Lee, Joon Y

    2015-12-01

    The incidence of intraoperative complications in cervical spine surgery is low. However, when they do occur, such complications have the potential for causing considerable morbidity and mortality. Spine surgeons should be familiar with methods of minimizing such complications. Furthermore, if they do occur, surgeons must be prepared to immediately treat each potential complication to reduce any associated morbidity. PMID:26519429

  13. Fusion of intraoperative force sensoring, surface reconstruction and biomechanical modeling

    NASA Astrophysics Data System (ADS)

    Röhl, S.; Bodenstedt, S.; Küderle, C.; Suwelack, S.; Kenngott, H.; Müller-Stich, B. P.; Dillmann, R.; Speidel, S.

    2012-02-01

    Minimally invasive surgery is medically complex and can heavily benefit from computer assistance. One way to help the surgeon is to integrate preoperative planning data into the surgical workflow. This information can be represented as a customized preoperative model of the surgical site. To use it intraoperatively, it has to be updated during the intervention due to the constantly changing environment. Hence, intraoperative sensor data has to be acquired and registered with the preoperative model. Haptic information which could complement the visual sensor data is still not established. In addition, biomechanical modeling of the surgical site can help in reflecting the changes which cannot be captured by intraoperative sensors. We present a setting where a force sensor is integrated into a laparoscopic instrument. In a test scenario using a silicone liver phantom, we register the measured forces with a reconstructed surface model from stereo endoscopic images and a finite element model. The endoscope, the instrument and the liver phantom are tracked with a Polaris optical tracking system. By fusing this information, we can transfer the deformation onto the finite element model. The purpose of this setting is to demonstrate the principles needed and the methods developed for intraoperative sensor data fusion. One emphasis lies on the calibration of the force sensor with the instrument and first experiments with soft tissue. We also present our solution and first results concerning the integration of the force sensor as well as accuracy to the fusion of force measurements, surface reconstruction and biomechanical modeling.

  14. Intraoperative urodynamics in spinal cord surgery: a study of feasibility.

    PubMed

    Schaan, M; Boszczyk, B; Jaksche, H; Kramer, G; Günther, M; Stöhrer, M

    2004-02-01

    Intraoperative monitoring (IOM) of bladder function in spinal cord surgery is a challenging task due to vegetative influences, multilevel innervation and numerous supraspinal modulating factors. Despite routine use of urodynamics in neurosurgery for implantation of bladder stimulators or denervation of nerve fibres in spastic reflex bladders, application of IOM in patients with spinal cord tumours or tethered-cord syndrome is not widespread. Combining urodynamics with sphincter electromyography (EMG) in IOM enables identification of bladder efferents responsible for contraction and continence. We monitored four patients with ependymoma of the Cauda equina, one patient with tethered-cord syndrome and two patients with cervical intramedullary tumours. In all patients undergoing operations of the Cauda equina, identification of bladder efferents responsible for detrusor contraction was possible. There was good correlation between preoperative bladder dysfunction, preoperative urodynamics and intraoperative pressure increase by bladder contraction or latency between stimulation and contraction. This method proved unsuitable for intramedullary tumours where no contraction of the bladder could be observed while stimulating the spinal cord. Intraoperative monitoring of urodynamics is an effective tool for identifying bladder efferents in the Cauda equina. Intraoperative conclusions on bladder dysfunction through registration of pressure increase and latency are possible. PMID:14634852

  15. [Somatosensory evoked potentials and electromyography in spinal cord intraoperative monitoring].

    PubMed

    Szkiładź, E

    1997-01-01

    Intraoperative monitoring can be defined as an application of several electroneurophysiological techniques for nervous system monitoring throughout the surgery. The principal goal of monitoring is to identify new neurologic impairment early enough to find the cause and to prevent permanent deficits. This paper reviews monitoring techniques during surgery for spinal deformity. PMID:9446047

  16. High-accuracy registration of intraoperative CT imaging

    NASA Astrophysics Data System (ADS)

    Oentoro, A.; Ellis, R. E.

    2010-02-01

    Image-guided interventions using intraoperative 3D imaging can be less cumbersome than systems dependent on preoperative images, especially by needing neither potentially invasive image-to-patient registration nor a lengthy process of segmenting and generating a 3D surface model. In this study, a method for computer-assisted surgery using direct navigation on intraoperative imaging is presented. In this system the registration step of a navigated procedure was divided into two stages: preoperative calibration of images to a ceiling-mounted optical tracking system, and intraoperative tracking during acquisition of the 3D medical image volume. The preoperative stage used a custom-made multi-modal calibrator that could be optically tracked and also contained fiducial spheres for radiological detection; a robust registration algorithm was used to compensate for the very high false-detection rate that was due to the high physical density of the optical light-emitting diodes. Intraoperatively, a tracking device was attached to plastic bone models that were also instrumented with radio-opaque spheres; A calibrated pointer was used to contact the latter spheres as a validation of the registration. Experiments showed that the fiducial registration error of the preoperative calibration stage was approximately 0.1 mm. The target registration error in the validation stage was approximately 1.2 mm. This study suggests that direct registration, coupled with procedure-specific graphical rendering, is potentially a highly accurate means of performing image-guided interventions in a fast, simple manner.

  17. Integration of 3D intraoperative ultrasound for enhanced neuronavigation

    NASA Astrophysics Data System (ADS)

    Paulsen, Keith D.; Ji, Songbai; Hartov, Alex; Fan, Xiaoyao; Roberts, David W.

    2012-03-01

    True three-dimensional (3D) volumetric ultrasound (US) acquisitions stand to benefit intraoperative neuronavigation on multiple fronts. While traditional two-dimensional (2D) US and its tracked, hand-swept version have been recognized for many years to advantage significantly image-guided neurosurgery, especially when coregistered with preoperative MR scans, its unregulated and incomplete sampling of the surgical volume of interest have limited certain intraoperative uses of the information that are overcome through direct volume acquisition (i.e., through 2D scan-head transducer arrays). In this paper, we illustrate several of these advantages, including image-based intraoperative registration (and reregistration) and automated, volumetric displacement mapping for intraoperative image updating. These applications of 3D US are enabled by algorithmic advances in US image calibration, and volume rasterization and interpolation for multi-acquisition synthesis that will also be highlighted. We expect to demonstrate that coregistered 3D US is well worth incorporating into the standard neurosurgical navigational environment relative to traditional tracked, hand-swept 2D US.

  18. Warm Springs Creek, Idaho

    Warm Springs Creek is a tributary of the Big Wood River in south-central Idaho. It is one of eight sites at which the USGS is conducting an ecological assessment during the summer of 2014. Study results will be published in 2015....

  19. Warm and Cool Cityscapes

    ERIC Educational Resources Information Center

    Jubelirer, Shelly

    2012-01-01

    Painting cityscapes is a great way to teach first-grade students about warm and cool colors. Before the painting begins, the author and her class have an in-depth discussion about big cities and what types of buildings or structures that might be seen in them. They talk about large apartment and condo buildings, skyscrapers, art museums,…

  20. Warm and Cool Cityscapes

    ERIC Educational Resources Information Center

    Jubelirer, Shelly

    2012-01-01

    Painting cityscapes is a great way to teach first-grade students about warm and cool colors. Before the painting begins, the author and her class have an in-depth discussion about big cities and what types of buildings or structures that might be seen in them. They talk about large apartment and condo buildings, skyscrapers, art museums,

  1. Warming Up to Communication.

    ERIC Educational Resources Information Center

    Garner, Lucia Caycedo; Rusch, Debbie

    Daily warm-up exercises are advocated as a means of bridging the gap between previously unrelated activities outside the classroom and immersion into the second language, relaxing the class, and establishing a mood for communication. Variety, careful preparation, assuring that the students understand the activity, feeling free to discontinue an…

  2. Physics-based shape matching for intraoperative image guidance

    SciTech Connect

    Suwelack, Stefan Röhl, Sebastian; Bodenstedt, Sebastian; Reichard, Daniel; Dillmann, Rüdiger; Speidel, Stefanie; Santos, Thiago dos; Maier-Hein, Lena; Wagner, Martin; Wünscher, Josephine; Kenngott, Hannes; Müller, Beat P.

    2014-11-01

    Purpose: Soft-tissue deformations can severely degrade the validity of preoperative planning data during computer assisted interventions. Intraoperative imaging such as stereo endoscopic, time-of-flight or, laser range scanner data can be used to compensate these movements. In this context, the intraoperative surface has to be matched to the preoperative model. The shape matching is especially challenging in the intraoperative setting due to noisy sensor data, only partially visible surfaces, ambiguous shape descriptors, and real-time requirements. Methods: A novel physics-based shape matching (PBSM) approach to register intraoperatively acquired surface meshes to preoperative planning data is proposed. The key idea of the method is to describe the nonrigid registration process as an electrostatic–elastic problem, where an elastic body (preoperative model) that is electrically charged slides into an oppositely charged rigid shape (intraoperative surface). It is shown that the corresponding energy functional can be efficiently solved using the finite element (FE) method. It is also demonstrated how PBSM can be combined with rigid registration schemes for robust nonrigid registration of arbitrarily aligned surfaces. Furthermore, it is shown how the approach can be combined with landmark based methods and outline its application to image guidance in laparoscopic interventions. Results: A profound analysis of the PBSM scheme based on in silico and phantom data is presented. Simulation studies on several liver models show that the approach is robust to the initial rigid registration and to parameter variations. The studies also reveal that the method achieves submillimeter registration accuracy (mean error between 0.32 and 0.46 mm). An unoptimized, single core implementation of the approach achieves near real-time performance (2 TPS, 7–19 s total registration time). It outperforms established methods in terms of speed and accuracy. Furthermore, it is shown that the method is able to accurately match partial surfaces. Finally, a phantom experiment demonstrates how the method can be combined with stereo endoscopic imaging to provide nonrigid registration during laparoscopic interventions. Conclusions: The PBSM approach for surface matching is fast, robust, and accurate. As the technique is based on a preoperative volumetric FE model, it naturally recovers the position of volumetric structures (e.g., tumors and vessels). It cannot only be used to recover soft-tissue deformations from intraoperative surface models but can also be combined with landmark data from volumetric imaging. In addition to applications in laparoscopic surgery, the method might prove useful in other areas that require soft-tissue registration from sparse intraoperative sensor data (e.g., radiation therapy)

  3. Lumbar Lordosis of Spinal Stenosis Patients during Intraoperative Prone Positioning

    PubMed Central

    Lee, Su-Keon; Song, Kyung-Sub; Park, Byung-Moon; Lim, Sang-Youn; Jang, Geun; Lee, Beom-Seok; Moon, Seong-Hwan; Lee, Hwan-Mo

    2016-01-01

    Background To evaluate the effect of spondylolisthesis on lumbar lordosis on the OSI (Jackson; Orthopaedic Systems Inc.) frame. Restoration of lumbar lordosis is important for maintaining sagittal balance. Physiologic lumbar lordosis has to be gained by intraoperative prone positioning with a hip extension and posterior instrumentation technique. There are some debates about changing lumbar lordosis on the OSI frame after an intraoperative prone position. We evaluated the effect of spondylolisthesis on lumbar lordosis after an intraoperative prone position. Methods Sixty-seven patients, who underwent spinal fusion at the Department of Orthopaedic Surgery of Gwangmyeong Sungae Hospital between May 2007 and February 2012, were included in this study. The study compared lumbar lordosis on preoperative upright, intraoperative prone and postoperative upright lateral X-rays between the simple stenosis (SS) group and spondylolisthesis group. The average age of patients was 67.86 years old. The average preoperative lordosis was 43.5° (± 14.9°), average intraoperative lordosis was 48.8° (± 13.2°), average postoperative lordosis was 46.5° (± 16.1°) and the average change on the frame was 5.3° (± 10.6°). Results Among all patients, 24 patients were diagnosed with simple spinal stenosis, 43 patients with spondylolisthesis (29 degenerative spondylolisthesis and 14 isthmic spondylolisthesis). Between the SS group and spondylolisthesis group, preoperative lordosis, intraoperative lordosis and postoperative lordosis were significantly larger in the spondylolisthesis group. The ratio of patients with increased lordosis on the OSI frame compared to preoperative lordosis was significantly higher in the spondylolisthesis group. The risk of increased lordosis on frame was significantly higher in the spondylolisthesis group (odds ratio, 3.325; 95% confidence interval, 1.101 to 10.039; p = 0.033). Conclusions Intraoperative lumbar lordosis on the OSI frame with a prone position was larger in the SS patients than the spondylolisthesis patients, which also produced a larger postoperative lordosis angle after posterior spinal fusion surgery. An increase in lumbar lordosis on the OSI frame should be considered during posterior spinal fusion surgery, especially in spondylolisthesis patients. PMID:26929801

  4. Intraoperative tissue expansion in the surgical correction of craniosynostosis

    PubMed Central

    Doshier, Laura J; Fowler, Daniel; McEwan, Thomas; Baker, C Lynette; Muzaffar, Arshad R

    2015-01-01

    BACKGROUND: Wound healing complications can occur after calvarial vault expansion due to tension on the scalp flaps. OBJECTIVES: To compare wound healing outcomes in patients with craniosynostosis undergoing calvarial vault expansion with and without intraoperative tissue expansion of the scalp. METHODS: The present analysis was an institutional review board-approved, retrospective cohort study involving 40 consecutive patients at the University of Missouri Hospitals and Clinics (Columbia, Missouri, USA) who underwent calvarial vault expansion for nonsyndromic craniosynostosis between June 1, 2009 and June 30, 2012. Patients were divided into two sequential cohorts: the first 20 underwent calvarial vault expansion without intraoperative tissue expansion; the second 20 underwent calvarial vault expansion with intraoperative tissue expansion. The main outcome measures included presence or absence of wound healing complications (persistent scabbing or slow-healing wounds, hardware exposure, need for operative wound revision or healed but widened scars), with documented postoperative follow-up of at least three months. The primary end point was the presence of a well-healed scar; the secondary end point was the need for an operative revision. RESULTS: Patients in the intraoperative tissue expansion group had a higher percentage of well-healed scars (73.6%) than those in the nonexpansion group (42.1%) (P=0.0487). This difference was primarily due to scar widening in the nonexpansion group. CONCLUSIONS: The present study demonstrated that the use of intraoperative tissue expansion in patients with nonsyndromic craniosynostosis who underwent calvarial vault expansion resulted in a greater likelihood of a well-healed incision with a lower rate of poor scarring. PMID:25821768

  5. Transcutaneous vs. intraoperative quantitative ultrasound for staging bovine hepatic steatosis.

    PubMed

    Weijers, Gert; Starke, Alexander; Thijssen, Johan M; Haudum, Alois; Wohlsein, Peter; Rehage, Juergen; de Korte, Chris L

    2012-08-01

    The aim of this study was to test the hypothesis that quantitative analysis of transcutaneous (Transc) ultrasound (US) images can predict the liver fat content with similar accuracy and precision as using intraoperative (Intraop) US. The second goal was to investigate if a tissue mimicking phantom (TMP) might be used as reference for automatic gain compensation (AGC) vs. depth instead of using the data of a set of cows without hepatic alterations. A study was performed in post partum dairy cows (N = 151), as an animal model of human nonalcoholic fatty liver disease (NAFLD), to test these hypotheses. Five Transc and five Intraop US liver images were acquired in each animal and a liver biopsy was taken. In liver tissue samples, triacylglycerol (TAG) content was measured by biochemical analysis and hepatic alterations, other than hepatic steatosis, were excluded by clinical examination. Several preprocessing steps were performed before the ultrasound tissue characteristics (UTC) parameters of B-mode images were derived. Stepwise multiple linear regression analysis was performed on a training set (N = 76) and the results were used on the test group (N = 75) to predict the TAG content in the liver. In all cases, the residual attenuation coefficient (ResAtt) was the only selected parameter. Receiver operating characteristics (ROC) analysis was applied to assess the performance and area under the curve (AUC) of predicting TAG and to compare the sensitivity and specificity of the methods used. High ROC values for AUC (95%), sensitivity (87%) and specificity (83%) for both Intraop and Transc applications with control group as well as with phantom-based AGC were obtained. Consequently, it can be concluded that Transc results are equivalent to Intraop results. Furthermore, equivalent ROC values, when using TMP AGC, indicates the potential use of TMP-based corrections instead of normal group-based corrections. The high predictive values indicate that noninvasive quantitative US has a great potential for staging and screening on hepatic steatosis in cows. PMID:22749338

  6. Does ultrasongraphy predict intraoperative findings at cholecystectomy? An institutional review

    PubMed Central

    Stogryn, Shannon; Metcalfe, Jennifer; Vergis, Ashley; Hardy, Krista

    2016-01-01

    Background Ultrasonography (US) is the mainstay of biliary tract imaging, but few recent studies have tested its ability to diagnose acute cholecystitis (AC). Our objective was to determine how well a US diagnosis of AC correlates with the intraoperative diagnosis. We hypothesize that US underestimates this diagnosis, potentially leading to unexpected findings in the operating room (OR). Methods This retrospective review included all patients admitted to the acute care surgical service of a tertiary hospital in 2011 with suspected biliary pathology who underwent US and subsequent cholecystectomy. We determined the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of US using the intraoperative diagnosis as the gold standard. Further analysis identified which US findings were most predictive of an intraoperative diagnosis of AC. We used a recursive partitioning method with random forests to identify unique combinations of US findings that, together, are most predictive of AC. Results In total, 254 patients underwent US for biliary symptoms; 152 had AC diagnosed, and 143 (94%) of them underwent emergency surgery (median time to OR 23.03 hr). Ultrasonography predicted intraoperative findings with a sensitivity of 73.2%, specificity of 85.5% and PPV of 93.7%. The NPV (52.0%) was quite low. The US indicators most predictive of AC were a thick wall, a positive sonographic Murphy sign and cholelithiasis. Recursive partitioning demonstrated that a positive sonographic Murphy sign is highly predictive of intraoperative AC. Conclusion Ultrasonography is highly sensitive and specific for diagnosing AC. The poor NPV confirms our hypothesis that US can underestimate AC. PMID:26574703

  7. Role of intraoperative transesophageal echocardiography in pediatric cardiac surgery

    PubMed Central

    Jijeh, Abdulraouf M.Z.; Omran, Ahmad S.; Najm, Hani K.; Abu-Sulaiman, Riyadh M.

    2015-01-01

    Background Intraoperative transesophageal echocardiography (TEE) has a major role in detecting residual lesions during and/or after pediatric cardiac surgery. Methods All pediatric patients who underwent cardiac surgery between July 2001 and December 2008 were reviewed. The records of surgical procedure, intraoperative TEE, and predischarge transthoracic echocardiograms were reviewed to determine minor and major residual cardiac lesions after surgical repair. Results During the study period, a total of 2268 pediatric cardiac patients were operated in our center. Mean age was 21 months (from 1 day to 14 years). Of these patients, 1016 (48%) had preoperative TEE and 1036 (46%) were evaluated by intraoperative echocardiography (TEE or epicardial study). We identified variations between TEE and preoperative transthoracic echocardiography in 14 patients (1.3%). Only one surgical procedure was cancelled after atrial septal defect exclusion. The other 13 patients had minor variation from their surgical plan. Major residual lesions requiring surgical revision were detected in 41 patients (3.9%), with the following primary diagnoses: tetralogy of Fallot in 12 patients (29%), atrioventricular septal defect in seven patients (17%), ventricular septal defect in seven patients (17%), double outlet right ventricle in two patients (5%), Shone complex in two patients (5%), subaortic stenosis in two patients (5%), mitral regurgitation in two patients (5%), pulmonary atresia in two patients (5%), and five patients (12%) with other diagnoses. Conclusion Intraoperative TEE has a major impact in pediatric cardiac surgery to detect significant residual lesions. Preoperative TEE has a limited role in case of a high quality preoperative transthoracic echocardiography. We recommend routine use of intraoperative TEE during and/or after intracardiac repair in children. PMID:27053898

  8. Identification alone versus intraoperative neuromonitoring of the recurrent laryngeal nerve during thyroid surgery: experience of 2034 consecutive patients

    PubMed Central

    2014-01-01

    Background The aim of this study was to evaluate the ability of intraoperative neuromonitoring in reducing the postoperative recurrent laryngeal nerve palsy rate by a comparison between patients submitted to thyroidectomy with intraoperative neuromonitoring and with routine identification alone. Methods Between June 2007 and December 2012, 2034 consecutive patients underwent thyroidectomy by a single surgical team. We compared patients who have had neuromonitoring and patients who have undergone surgery with nerve visualization alone. Patients in which neuromonitoring was not utilized (Group A) were 993, patients in which was utilized (group B) were 1041. Results In group A 28 recurrent laryngeal nerve injuries were observed (2.82%), 21 (2.11%) transient and 7 (0.7%) permanent. In group B 23 recurrent laryngeal nerve injuries were observed (2.21%), in 17 cases (1.63%) transient and in 6 (0.58%) permanent. Differences were not statistically significative. Conclusions Visual nerve identification remains the gold standard of recurrent laryngeal nerve management in thyroid surgery. Neuromonitoring helps to identify the nerve, in particular in difficult cases, but it did not decrease nerve injuries compared with visualization alone. Future studies are warranted to evaluate the benefit of intraoperative neuromonitoring in thyroidectomy, especially in conditions in which the recurrent nerve is at high risk of injury. PMID:24942225

  9. Plant community responses to experimental warming across the tundra biome

    PubMed Central

    Walker, Marilyn D.; Wahren, C. Henrik; Hollister, Robert D.; Henry, Greg H. R.; Ahlquist, Lorraine E.; Alatalo, Juha M.; Bret-Harte, M. Syndonia; Calef, Monika P.; Callaghan, Terry V.; Carroll, Amy B.; Epstein, Howard E.; Jónsdóttir, Ingibjörg S.; Klein, Julia A.; Magnússon, Borgþór; Molau, Ulf; Oberbauer, Steven F.; Rewa, Steven P.; Robinson, Clare H.; Shaver, Gaius R.; Suding, Katharine N.; Thompson, Catharine C.; Tolvanen, Anne; Totland, Ørjan; Turner, P. Lee; Tweedie, Craig E.; Webber, Patrick J.; Wookey, Philip A.

    2006-01-01

    Recent observations of changes in some tundra ecosystems appear to be responses to a warming climate. Several experimental studies have shown that tundra plants and ecosystems can respond strongly to environmental change, including warming; however, most studies were limited to a single location and were of short duration and based on a variety of experimental designs. In addition, comparisons among studies are difficult because a variety of techniques have been used to achieve experimental warming and different measurements have been used to assess responses. We used metaanalysis on plant community measurements from standardized warming experiments at 11 locations across the tundra biome involved in the International Tundra Experiment. The passive warming treatment increased plant-level air temperature by 1-3°C, which is in the range of predicted and observed warming for tundra regions. Responses were rapid and detected in whole plant communities after only two growing seasons. Overall, warming increased height and cover of deciduous shrubs and graminoids, decreased cover of mosses and lichens, and decreased species diversity and evenness. These results predict that warming will cause a decline in biodiversity across a wide variety of tundra, at least in the short term. They also provide rigorous experimental evidence that recently observed increases in shrub cover in many tundra regions are in response to climate warming. These changes have important implications for processes and interactions within tundra ecosystems and between tundra and the atmosphere. PMID:16428292

  10. Intraoperative /sup 99m/Tc bone imaging in the treatment of benign osteoblastic tumors

    SciTech Connect

    Sty, J.; Simons, G.

    1982-05-01

    Benign bone tumors can be successfully treated by local resection with the use of intraoperative bone imaging. Intraoperative bone imaging provided accurate localization of an osteoid osteoma in a patella of a 16-year-old girl when standard radiographs failed to demonstrate the lesion. In a case of osteoblastoma of the sacrum in a 12-year old girl, intraoperative scanning was used repeatedly to guide completeness of resection. In these cases in which routine intraoperative radiographs would have failed, intraoperative scanning proved to be essential for success.

  11. Climate science: Pacemakers of warming

    NASA Astrophysics Data System (ADS)

    Brnnimann, Stefan

    2015-02-01

    In the first decades of the twentieth century, the Earth warmed rapidly. A coral-based climate proxy record of westerly winds over the equatorial Pacific suggests that wind strength and warming rate were linked, as they are today.

  12. PERENNIAL WARM-SEASON GRASSES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Warm-season grasses and can be used to augment the forage supply for grazing livestock operations in the northeastern U.S. Much of what is known about warm season grass production and management in the northeastern US was obtained from a soil conservation or wildlife habitat perspective. Warm-seas...

  13. Intraoperative Neuromonitoring for Superior Semicircular Canal Dehiscence and Hearing Outcomes

    PubMed Central

    Wenzel, Angela; Ward, Bryan K.; Ritzl, Eva K.; Gutierrez-Hernandez, Sergio; Della Santina, Charles C.; Minor, Lloyd B.; Carey, John P.

    2016-01-01

    Background Recent findings in patients with superior semicircular canal dehiscence (SCD) have shown an elevated ratio of summating potential (SP) to action potential (AP), as measured by electrocochleography (ECochG). Changes in this ratio can be seen during surgical intervention. The objective of this study was to evaluate the utility of intraoperative ECochG and auditory brainstem response (ABR) as predictive tools for postoperative hearing outcomes after surgical plugging via middle cranial fossa approach for SCD syndrome (SCDS). Methods This was a review of 34 cases (33 patients) in which reproducible intraoperative ECochG recordings were obtained during surgery. Diagnosis of SCDS was based on history, physical examination, vestibular function testing, and computed tomography imaging. Simultaneous intraoperative ECochG and ABR were performed. Pure-tone audiometry was performed preoperatively and at least 1 month postoperatively, and air-bone gap (ABG) was calculated. Changes in SP/AP ratio, SP amplitude, and ABR wave I latency were compared with changes in pure-tone average and ABG before and after surgery. Results Median SP/AP ratio of affected ears was 0.62 (interquartile range [IQR], 0.45–0.74) and decreased immediately after surgical plugging of the affected canal to 0.42 (IQR, 0.29–0.52; p < 0.01). Contralateral SP/AP ratio before plugging was 0.33 (IQR, 0.25–0.42) and remained unchanged at the conclusion of surgery (0.30; IQR, 0.25–0.35; p = 0.32). Intraoperative changes in ABR wave I latency and SP amplitude did not predict changes in pure-tone average or ABG after surgery (p > 0.05). Conclusion This study confirmed the presence of an elevated SP/AP ratio in ears with SCDS. The SP/AP ratio commonly decreases during plugging. However, an intraoperative decrease in SP/AP does not appear to be sensitive to either the beneficial decrease in ABGs or the mild high-frequency sensory loss that can occur in patients undergoing surgical plugging of the superior semicircular canal. Future work will determine the value of intraoperative ECochG in predicting changes in vestibular function. PMID:25333320

  14. The effects of warmed intravenous fluids, combined warming (warmed intravenous fluids with humid-warm oxygen), and pethidine on the severity of shivering in general anesthesia patients in the recovery room

    PubMed Central

    Nasiri, Ahmad; Akbari, Ayob; Sharifzade, GholamReza; Derakhshan, Pooya

    2015-01-01

    Background: Shivering is a common complication of general and epidural anesthesia. Warming methods and many drugs are used for control of shivering in the recovery room. The present study is a randomized clinical trial aimed to investigate the effects of two interventions in comparison with pethidine which is the routine treatment on shivering in patients undergoing abdominal surgery with general anesthesia. Materials and Methods: Eighty-seven patients undergoing abdominal surgery by general anesthesia were randomly assigned to three groups (two intervention groups in comparison with pethidine as routine). Patients in warmed intravenous fluids group received pre-warmed Ringer serum (38°C), patients in combined warming group received pre-warmed Ringer serum (38°C) accompanied by humid-warm oxygen, and patients in pethidine group received intravenous pethidine routinely. The elapsed time of shivering and some hemodynamic parameters of the participants were assessed for 20 min postoperatively in the recovery room. Then the collected data were analyzed by software SPSS (v. 16) with the significance level being P < 0.05. Results: The mean of elapsed time in the warmed intravenous serum group, the combined warming group, and the pethidine group were 7 (1.5) min, 6 (1.5) min, and 2.8 (0.7) min, respectively, which was statistically significant (P < 0.05). The body temperatures in both combined warming and pethidine groups were increased significantly (P < 0.05). Conclusions: Combined warming can be effective in controlling postoperative shivering and body temperature increase. PMID:26793258

  15. Global Warming And Meltwater

    NASA Astrophysics Data System (ADS)

    Bratu, S.

    2012-04-01

    In order to find new approaches and new ideas for my students to appreciate the importance of science in their daily life, I proposed a theme for them to debate. They had to search for global warming information and illustrations in the media, and discuss the articles they found in the classroom. This task inspired them to search for new information about this important and timely theme in science. I informed my students that all the best information about global warming and meltwater they found would be used in a poster that would help us to update the knowledge base of the Physics laboratory. I guided them to choose the most eloquent images and significant information. Searching and working to create this poster, the students arrived to better appreciate the importance of science in their daily life and to critically evaluate scientific information transmitted via the media. In the poster we created, one can find images, photos and diagrams and some interesting information: Global warming refers to the rising average temperature of the Earth's atmosphere and oceans and its projected evolution. In the last 100 years, the Earth's average surface temperature increased by about 0.8 °C with about two thirds of the increase occurring over just the last three decades. Warming of the climate system is unequivocal, and scientists are more than 90% certain most of it is caused by increasing concentrations of greenhouse gases produced by human activities such as deforestation and burning fossil fuel. They indicate that during the 21st century the global surface temperature is likely to rise a further 1.1 to 2.9 °C for the lowest emissions scenario and 2.4 to 6.4 °C for the highest predictions. An increase in global temperature will cause sea levels to rise and will change the amount and pattern of precipitation, and potentially result in expansion of subtropical deserts. Warming is expected to be strongest in the Arctic and would be associated with continuing decrease of glaciers, permafrost and sea ice. Other likely effects of the warming include more frequent occurrences of extreme weather events including heat waves, droughts and heavy rainfall events, species extinctions due to shifting temperature regimes, and changes in agricultural yields. Meltwater is the water released by the melting of snow or ice, including glacial ice and ice shelves in the oceans. Meltwater is often found in the ablation zone of glaciers, where the rate of snow cover is reduced. In a report published in June 2007, the United Nations Environment Program estimated that global warming could lead to 40% of the world's population being affected by the loss of glaciers, snow and the associated meltwater in Asia. This is one of many activities of the physics laboratory that the students of our high school are involved in.

  16. Abrupt warming of the Red Sea

    NASA Astrophysics Data System (ADS)

    Raitsos, D. E.; Hoteit, I.; Prihartato, P. K.; Chronis, T.; Triantafyllou, G.; Abualnaja, Y.

    2011-07-01

    Coral reef ecosystems, often referred to as “marine rainforests,” concentrate the most diverse life in the oceans. Red Sea reef dwellers are adapted in a very warm environment, fact that makes them vulnerable to further and rapid warming. The detection and understanding of abrupt temperature changes is an important task, as ecosystems have more chances to adapt in a slowly rather than in a rapid changing environment. Using satellite derived sea surface and ground based air temperatures, it is shown that the Red Sea is going through an intense warming initiated in the mid-90s, with evidence for an abrupt increase after 1994 (0.7°C difference pre and post the shift). The air temperature is found to be a key parameter that influences the Red Sea marine temperature. The comparisons with Northern Hemisphere temperatures revealed that the observed warming is part of global climate change trends. The hitherto results also raise additional questions regarding other broader climatic impacts over the area.

  17. Intraoperative tumor lysis syndrome in a child with Wilms' tumor

    PubMed Central

    Dhar, Mridul; Prakash, Shashi; Pandey, Vaibhav; Pai, Vishal Krishna

    2016-01-01

    Tumor lysis syndrome in an onco-metabolic emergency resulting from massive lysis of rapidly proliferating malignant cells seen commonly in patients with hematological malignancies such as acute lymphocytic leukemia and Burkitt's lymphoma and is quite rare in solid tumors. Spontaneous development of tumor lysis has been described among other trigger factors such as corticosteroid therapy, anesthesia, tumor manipulation during surgery and pyrexia. We describe such a case in a 5-year-old boy posted for excision and staging of a massive Wilms' tumor who developed a hyperkalemic cardiac arrest during the procedure and its subsequent intraoperative and postoperative management. Intraoperative cardiac arrest is a stressful situation for both the anesthesiologist and the surgeon, more so when it involves a child. The aim of this report is to make the anesthesiologist aware of the possibility and occurrence of such a phenomenon in children and be adequately prepared for such an emergency. PMID:26957712

  18. Intraoperative Functional Mapping and Monitoring during Glioma Surgery

    PubMed Central

    SAITO, Taiichi; MURAGAKI, Yoshihiro; MARUYAMA, Takashi; TAMURA, Manabu; NITTA, Masayuki; OKADA, Yoshikazu

    2015-01-01

    Glioma surgery represents a significant advance with respect to improving resection rates using new surgical techniques, including intraoperative functional mapping, monitoring, and imaging. Functional mapping under awake craniotomy can be used to detect individual eloquent tissues of speech and/or motor functions in order to prevent unexpected deficits and promote extensive resection. In addition, monitoring the patients neurological findings during resection is also very useful for maximizing the removal rate and minimizing deficits by alarming that the touched area is close to eloquent regions and fibers. Assessing several types of evoked potentials, including motor evoked potentials (MEPs), sensory evoked potentials (SEPs) and visual evoked potentials (VEPs), is also helpful for performing surgical monitoring in patients under general anesthesia (GA). We herein review the utility of intraoperative mapping and monitoring the assessment of neurological findings, with a particular focus on speech and the motor function, in patients undergoing glioma surgery. PMID:25744346

  19. Intraoperative Dexmedetomidine Promotes Postoperative Analgesia in Patients After Abdominal Colectomy

    PubMed Central

    Ge, Dong-Jian; Qi, Bin; Tang, Gang; Li, Jin-Yu

    2015-01-01

    Abstract Surgery-induced acute postoperative pain may lead to prolonged convalescence. The present study was designed to investigate the effects of intraoperative dexmedetomidine on postoperative analgesia following abdominal colectomy surgeries. Eighty patients scheduled for abdominal colectomy surgery under general anesthesia were divided into 2 groups, which were maintained using propofol/remifentanil/dexmedetomidine (PRD) or propofol/remifentanil/saline (PRS). During surgery, patients in the PRD group had a lower bispectral index (BIS) value, which indicated a deeper anesthetic state, and a higher sedation score right after extubation than patients in the PRS group. During the first 24 hours post surgery, PRD patients consumed less morphine in patient-controlled analgesia (PCA) and had a lower score in the visual analog scale (VAS) testing than their controls from the PRS group. Intraoperative administration of dexmedetomidine appears to promote the analgesic property of morphine-based PCA in patients after abdominal colectomy. PMID:26376397

  20. Intraoperative tumor lysis syndrome in a child with Wilms' tumor.

    PubMed

    Dhar, Mridul; Prakash, Shashi; Pandey, Vaibhav; Pai, Vishal Krishna

    2016-01-01

    Tumor lysis syndrome in an onco-metabolic emergency resulting from massive lysis of rapidly proliferating malignant cells seen commonly in patients with hematological malignancies such as acute lymphocytic leukemia and Burkitt's lymphoma and is quite rare in solid tumors. Spontaneous development of tumor lysis has been described among other trigger factors such as corticosteroid therapy, anesthesia, tumor manipulation during surgery and pyrexia. We describe such a case in a 5-year-old boy posted for excision and staging of a massive Wilms' tumor who developed a hyperkalemic cardiac arrest during the procedure and its subsequent intraoperative and postoperative management. Intraoperative cardiac arrest is a stressful situation for both the anesthesiologist and the surgeon, more so when it involves a child. The aim of this report is to make the anesthesiologist aware of the possibility and occurrence of such a phenomenon in children and be adequately prepared for such an emergency. PMID:26957712

  1. Intraoperative assessment of maxillary perfusion during Le Fort I osteotomy.

    PubMed

    Dodson, T B; Neuenschwander, M C; Bays, R A

    1994-08-01

    Intraoperative maxillary blood flow was measured using laser Doppler flowmetry (LDF) in two groups of patients undergoing orthognathic surgery. Group 1 (n = 14) consisted of patients undergoing Le Fort I osteotomy and group 2 (n = 8) consisted of patients undergoing isolated mandibular osteotomies. In group 1, the mean gingival blood flow (GBF) decreased significantly over time during the course of the operation from 29.5 mL/min/100 g of tissue to 13.2 mL/min/100 g of tissue (P = .0001). The mean GBF did not change significantly over time in group 2 (P = .39). The results of this study demonstrate that 1) LDF may be used to measure intraoperative GBF during Le Fort I osteotomy with an acceptable level of variability, and 2) maxillary GBF decreased significantly over time during Le Fort I osteotomy procedures. PMID:8040736

  2. Transsphenoidal pituitary resection with intraoperative MR guidance: preliminary results

    NASA Astrophysics Data System (ADS)

    Pergolizzi, Richard S., Jr.; Schwartz, Richard B.; Hsu, Liangge; Wong, Terence Z.; Black, Peter M.; Martin, Claudia; Jolesz, Ferenc A.

    1999-05-01

    The use of intraoperative MR image guidance has the potential to improve the precision, extent and safety of transsphenoidal pituitary resections. At Brigham and Women's Hospital, an open-bore configuration 0.5T MR system (SIGNA SP, GE Medical Systems, Milwaukee, WI) has been used to provide image guidance for nine transsphenoidal pituitary adenoma resections. The intraoperative MR system allowed the radiologist to direct the surgeon toward the sella turcica successfully while avoiding the cavernous sinus, optic chiasm and other sensitive structures. Imaging performed during the surgery monitored the extent of resection and allowed for removal of tumor beyond the surgeon's view in five cases. Dynamic MR imaging was used to distinguish residual tumor from normal gland and postoperative changes permitting more precise tumor localization. A heme-sensitive long TE gradient echo sequence was used to evaluate for the presence of hemorrhagic debris. All patients tolerated the procedure well without significant complications.

  3. Intraoperative blood loss in orthotopic liver transplantation: The predictive factors

    PubMed Central

    Pandey, Chandra Kant; Singh, Anshuman; Kajal, Kamal; Dhankhar, Mandeep; Tandon, Manish; Pandey, Vijay Kant; Karna, Sunaina Tejpal

    2015-01-01

    Liver transplantation has been associated with massive blood loss and considerable transfusion requirements. Bleeding in orthotopic liver transplantation is multifactorial. Technical difficulties inherent to this complex surgical procedure and pre operative derangements of the primary and secondary coagulation system are thought to be the principal causes of perioperative hemorrhage. Intraoperative practices such as massive fluid resuscitation and resulting hypothermia and hypocalcemia secondary to citrate toxicity further aggravate the preexisting coagulopathy and worsen the perioperative bleeding. Excessive blood loss and transfusion during orthotopic liver transplant are correlated with diminished graft survival and increased septic episodes and prolonged ICU stay. With improvements in surgical skills, anesthetic technique, graft preservation, use of intraoperative cell savers and overall perioperative management, orthotopic liver transplant is now associated with decreased intra operative blood losses. The purpose of this review is to discuss the risk factors predictive of increased intra operative bleeding in patients undergoing orthotopic liver transplant. PMID:26131330

  4. Segmentation-Based Registration of Organs in Intraoperative Video Sequences

    SciTech Connect

    Goddard Jr, James Samuel; Gee, Timothy Felix; Wang, Hengliang; Gorbach, Alexander M

    2006-01-01

    Intraoperative optical imaging of exposed organs in visible, near-infrared, and infrared (IR) wavelengths in the body has the potential to be use-ful for real-time assessment of organ viability and image guidance during surgical intervention. However, the motion of the internal organs presents significant challenges for fast analysis of recorded 2D video sequences. The movement observed during surgery, due to respiration, cardiac motion, blood flow, and mechanical shift accompanying the surgical intervention, causes organ reflection in the image sequence, making optical measurements for further analysis challenging. Correcting alignment is difficult in that the motion is not uniform over the image. This paper describes a Canny edge-based method for segmentation of the specific organ or region under study, along with a moment-based registration method for the segmented region. Experimental results are provided for a set of intraoperative IR image sequences.

  5. Toward Intraoperative Image-Guided Transoral Robotic Surgery

    PubMed Central

    Liu, Wen P.; Reaugamornrat, Sureerat; Deguet, Anton; Sorger, Jonathan M.; Siewerdsen, Jeffrey H.; Richmon, Jeremy; Taylor, Russell H.

    2014-01-01

    This paper presents the development and evaluation of video augmentation on the stereoscopic da Vinci S system with intraoperative image guidance for base of tongue tumor resection in transoral robotic surgery (TORS). Proposed workflow for image-guided TORS begins by identifying and segmenting critical oropharyngeal structures (e.g., the tumor and adjacent arteries and nerves) from preoperative computed tomography (CT) and/or magnetic resonance (MR) imaging. These preoperative planned data can be deformably registered to the intraoperative endoscopic view using mobile C-arm cone-beam computed tomography (CBCT) [1, 2]. Augmentation of TORS endoscopic video defining surgical targets and critical structures has the potential to improve navigation, spatial orientation, and confidence in tumor resection. Experiments in animal specimens achieved statistically significant improvement in target localization error when comparing the proposed image guidance system to simulated current practice. PMID:25525474

  6. Intraoperative MRI in pediatric neurosurgery—an update

    PubMed Central

    2014-01-01

    Since the advent of intraoperative magnetic resonance imaging (ioMRI) at the Brigham and Women’s Hospital in 1994, ioMRI has spread widely and in many different forms. This article traces the developmental history of ioMRI and reviews the relevant literature regarding it’s effectiveness in pediatric neurosurgery. While of considerable expense, current trends in healthcare essentially mandate the use of ioMRI in a growing number of cases. PMID:26835341

  7. Necrotizing Fasciitis: A Life-threatening Complication of Intraoperative Electromyography

    PubMed Central

    Shoakazemi, Alireza; Tubbs, R. Shane; Wingerson, Mary; Ajayi, Olaide; Zwillman, Michael E; Gottlieb, Jourdan; Hanscom, David

    2016-01-01

    Intraoperative neurophysiological monitoring is a commonly used practice during spine surgery. Complications of electromyography (EMG) needle electrode placement are very uncommon. We present a patient who was infected with necrotizing fasciitis in her left thigh due to an EMG needle electrode during a two-stage complex spine procedure. This case demonstrates that providers should continue to meticulously adhere to protocol when inserting and removing EMG needles, but also be cognizant during postoperative observation of the possibility of infection caused by EMG needles.

  8. Intraoperative neurophysiologic monitoring with Hoffmann reflex during thoracic spine surgery.

    PubMed

    Feyissa, Anteneh M; Tummala, Sudhakar

    2015-06-01

    The aim of this study was examine the role of Hoffmann reflex (H-reflex) monitoring in identifying intraoperative spinal cord injury and predicting postoperative neurological outcome in patients undergoing thoracic spine surgery. Despite the physiologic basis for the use of H-reflex to monitor spinal motor pathways, there are only a few reports highlighting its application as an intraoperative neuromonitoring tool. We retrospectively reviewed the electronic medical records of 19 consecutive patients who underwent thoracic spine surgery for metastatic thoracic spinal tumors between 2011 and 2013 at the MD Anderson Cancer Center. H-waves and somatosensory evoked potentials (SSEP) were simultaneously monitored in our series consisting of four female and 15 male patients aged 10-71 years. In 10 of 19 patients, bilateral H-waves and SSEP were stable throughout the monitoring. Five of 19 patients had a <50% transient reduction in H-wave amplitude that later returned to baseline. SSEP were absent from baseline throughout surgery in two of 19 patients. In our series, neither general anesthesia nor low dose muscle relaxants interfered with the H-waves. At 3 and 6 month follow-ups, none of the patients exhibited new postoperative neurological deficits. Stable intraoperative H-waves are suggestive of preserved postoperative neurologic outcomes. Intraoperative H-reflex monitoring could be a reasonable alternative especially when motor evoked potentials are unattainable. Given its greater sensitivity to spinal cord ischemia, relatively low cost and ease of acquisition, H-reflex monitoring could be a useful adjunct in during thoracic spine surgeries. PMID:25769258

  9. Pediatric intraoperative floppy iris syndrome associated with persistent pupillary membrane.

    PubMed

    Motley, W Walker; Melson, Andrew T

    2011-04-01

    Intraoperative floppy iris syndrome (IFIS) occurring during cataract surgery in adults has been widely reported in association with tamsulosin and other α-1(a) adrenergic antagonists; however, only one case of pediatric IFIS has been previously reported and was associated with congenital cataract. We report a case of a 1-month old girl with IFIS associated with bilateral persistent pupillary membranes without cataracts and the use of preoperative topical phenylephrine and pilocarpine for IFIS prophylaxis. PMID:21463957

  10. Modern preoperative and intraoperative management of hereditary angioedema.

    PubMed

    Szema, Anthony M; Paz, George; Merriam, Louis; Stellaccio, Francis; Jen, James

    2009-01-01

    Hereditary angioedema (HAE), deficiency of C1 esterase inhibitor, poses a risk of airway compromise during trauma, including surgery, due to activation of the complement cascade. Classical surgical management includes emergent/slash tracheostomy and cricothyrotomy, associated with high complication rates. We provide here an evidence-based review of available medical literature to construct guidelines for managing patients with HAE pre- and intra-operatively. We also describe our experience with a patient for whom we cared using these guidelines. Our objective was to explain new preventive measures to prevent airway compromise in HAE and their level of evidence for averting potential therapeutic misadventure. We analyzed PUBMED literature regarding airway management and etiology of angioedema and its prevention, followed by application of guidelines based on these data in a patient with HAE undergoing inguinal hernia repair. An analysis of contemporary literature yielded key points: (1) using a Cook Exchange catheter to facilitate re-intubation, (2) measuring cuff leak pressure to verify whether airway pressure had increased during surgery, (3) visualizing the airway directly using a fiberoptic laryngoscope connected to a digital flat-screen monitor for real-time assessment, (4) following conventional dictum to double stanozolol dosages 2 weeks before admission, (5) administering fresh frozen plasma pre- and intraoperatively, and (6) preparing recombinant C1 esterase inhibitor for instantaneous intraoperative use; and using FDA-approved human-derived C1-esterase inhibitor prophylactically. Biotechnology in the form of novel but currently available and in-practice medical devices, as well as new therapeutic agents, have expanded the armamentarium for safely managing patients with HAE pre- and intraoperatively. PMID:19368763

  11. A tool for intraoperative visualization of registration results

    NASA Astrophysics Data System (ADS)

    King, Franklin; Lasso, Andras; Pinter, Csaba; Fichtinger, Gabor

    2014-03-01

    PURPOSE: Validation of image registration algorithms is frequently accomplished by the visual inspection of the resulting linear or deformable transformation due to the lack of ground truth information. Visualization of transformations produced by image registration algorithms during image-guided interventions allows for a clinician to evaluate the accuracy of the result transformation. Software packages that perform the visualization of transformations exist, but are not part of a clinically usable software application. We present a tool that visualizes both linear and deformable transformations and is integrated in an open-source software application framework suited for intraoperative use and general evaluation of registration algorithms. METHODS: A choice of six different modes are available for visualization of a transform. Glyph visualization mode uses oriented and scaled glyphs, such as arrows, to represent the displacement field in 3D whereas glyph slice visualization mode creates arrows that can be seen as a 2D vector field. Grid visualization mode creates deformed grids shown in 3D whereas grid slice visualization mode creates a series of 2D grids. Block visualization mode creates a deformed bounding box of the warped volume. Finally, contour visualization mode creates isosurfaces and isolines that visualize the magnitude of displacement across a volume. The application 3D Slicer was chosen as the platform for the transform visualizer tool. 3D Slicer is a comprehensive open-source application framework developed for medical image computing and used for intra-operative registration. RESULTS: The transform visualizer tool fulfilled the requirements for quick evaluation of intraoperative image registrations. Visualizations were generated in 3D Slicer with little computation time on realistic datasets. It is freely available as an extension for 3D Slicer. CONCLUSION: A tool for the visualization of displacement fields was created and integrated into 3D Slicer, facilitating the validation of image registration algorithms within a comprehensive application framework suited for intraoperative use.

  12. Intraoperative findings in revision chronic otitis media surgery.

    PubMed

    Faramarzi, Abolhassan; Motasaddi-Zarandy, Masoud; Khorsandi, Mohammad-Taghi

    2008-03-01

    In this study, we reviewed the surgical findings in a series of revision tympanomastoidectomy to determine the most common causes of failure in chronic otitis media surgery. The intraoperative findings at revision mastoidectomy with tympanoplasty of 116 patients were analyzed. The most common sites of pathologic tissue at revision surgery (with cholesteatoma and/ or granulation tissue) were unexenterated cells of the sinodural angle. The most common mechanical cause of retention of debris in canal wall down procedures was facial ridge. PMID:18298298

  13. Misleading FLAIR imaging pattern after glioma surgery with intraoperative MRI.

    PubMed

    Lescher, Stephanie; Jurcoane, Alina; Schniewindt, Sonja; Senft, Christian; Hattingen, Elke

    2016-01-01

    Intraoperative MRI (iMRI) allows a more detailed appreciation of the extent of resection than does conventional neurosurgery and results in longer overall survival in patients with malignant glioma. However, it is unknown whether the intraoperative application of contrast agent influences the early postsurgical MRI. The preceding iMRI could alter the signals of MR sequences in the early postsurgical MRI, especially in sequences influenced by T1 contrast. Hereby, we investigate such iMRI-induced influences on the fluid-attenuated inversion recovery (FLAIR) sequence. We retrospectively analyzed postsurgical T2w, T1w, and FLAIR images by visual inspection and by signal measurements in 46 patients with malignant gliomas after tumor resection. Of these, n = 25 patients were operated with conventional microsurgery, and n = 21 patients were operated with contrast-enhanced iMRI-guided microsurgery. We measured signal intensity in the resection cavity, in the cerebrospinal fluid (CSF) of the ventricles, and in the normal brain tissue contralateral to the tumor-bearing hemisphere on axial FLAIR images and T1-weighted and T2-weighted images. In 18 patients, the FLAIR sequence revealed hyperintense signal changes of the CSF in the subarachnoid or ventricular spaces. Seventeen of these 18 patients had received intraoperative MRI. In both FLAIR and T1-weighted images, the signal of the CSF in the ventricles was significantly higher in patients with iMRI than in patients without iMRI. The intraoperative application of contrast agent that is used for iMRI significantly influences postsurgical MRI within the first 72 h. We found hyperintense signal changes of the CSF in the FLAIR sequence in the subarachnoid and intraventricular spaces mimicking subarachnoid hemorrhage. The findings may result in a misdiagnosis of subarachnoid hemorrhage (SAH) in these patients. PMID:26201972

  14. Global warming - A reduced threat

    SciTech Connect

    Michaels, P.J.; Stooksbury, D.E. )

    1992-10-01

    Issues associated with global warming are analyzed focusing on global and hemispheric temperature histories and trace gas concentrations; artificial warming from urban heat islands; high-latitude and diurnal temperatures; recent climate models; direct effects on vegetation of an increase in carbon dioxide; and compensatory cooling from other industrial products. Data obtained indicate that anthropogenerated sulfate emissions are mitigating some of the warming, and that increased cloudiness as a result of these emissions will further enhance night, rather than day, warming. It is noted that the sulfate emissions are not sufficient to explain all of the night warming. The sensitivity of climate to anthropogenerated aerosols, and the general lack of previously predicted warming, could drastically alter the debate on global warming in favor of less expensive policies. 61 refs.

  15. Prospective evaluation of intraoperative hemodynamics in liver transplantation with whole, partial and DCD grafts.

    PubMed

    Sainz-Barriga, M; Reyntjens, K; Costa, M G; Scudeller, L; Rogiers, X; Wouters, P; de Hemptinne, B; Troisi, R I

    2010-08-01

    The interaction of systemic hemodynamics with hepatic flows at the time of liver transplantation (LT) has not been studied in a prospective uniform way for different types of grafts. We prospectively evaluated intraoperative hemodynamics of 103 whole and partial LT. Liver graft hemodynamics were measured using the ultrasound transit time method to obtain portal (PVF) and arterial (HAF) hepatic flow. Measurements were recorded on the native liver, the portocaval shunt, following reperfusion and after biliary anastomosis. After LT HAF and PVF do not immediately return to normal values. Increased PVF was observed after graft implantation. Living donor LT showed the highest compliance to portal hyperperfusion. The amount of liver perfusion seemed to be related to the quality of the graft. A positive correlation for HAF, PVF and total hepatic blood flow with cardiac output was found (p = 0.001). Portal hypertension, macrosteatosis >30%, warm ischemia time and cardiac output, independently influence the hepatic flows. These results highlight the role of systemic hemodynamic management in LT to optimize hepatic perfusion, particularly in LDLT and split LT, where the highest flows were registered. PMID:20659091

  16. A biomechanical liver model for intraoperative soft tissue registration

    NASA Astrophysics Data System (ADS)

    Suwelack, Stefan; Talbot, Hugo; Röhl, Sebastian; Dillmann, Rüdiger; Speidel, Stefanie

    2011-03-01

    Organ motion due to respiration and contact with surgical instruments can significantly degrade the accuracy of image guided surgery. In most applications the ensuing soft tissue deformations have to be compensated in order to register preoperative planning data to the patient. Biomechanical models can be used to perform an accurate registration based on sparse intraoperative sensor data. Using elasticity theory, the approach can be formulated as a boundary value problem with displacement boundary conditions. In this paper, several models of the liver from the literature and a new simplified model are evaluated with regards to their application to intraoperative soft tissue registration. We construct finite element models of a liver phantom using the different material laws. Thereafter, typical deformation pattern that occur during surgery are imposed by applying displacement boundary conditions. A comparative numerical study shows that the maximal registration error of all non-linear models stays below 1.1mm, while the linear model produces errors up to 3.9mm. It can be concluded that linear elastic models are not suitable for the registration of the liver and that a geometrically non-linear formulation has to be used. Although the stiffness parameters of the non-linear materials differ considerably, the calculated displacement fields are very similar. This suggests that a difficult patient-specific parameterization of the model might not be necessary for intraoperative soft tissue registration. We also demonstrate that the new simplified model achieves nearly the same registration accuracy as complex quasi-linear viscoelastic models.

  17. Intraoperative Imaging in Neurosurgery: Where Will the Future Take Us?

    PubMed Central

    Jolesz, Ferenc A.

    2014-01-01

    Intraoperative MRI (ioMRI) dates back to the 1990s and since then has been successfully applied in neurosurgery for three primary reasons with the last one becoming the most significant today: (1) brain shift-corrected navigation, (2) monitoring/controlling thermal ablations, and (3) identifying residual tumor for resection. IoMRI, which today is moving into other applications, including treatment of vasculature and the spine, requires advanced 3 T MRI platforms for faster and more flexible image acquisitions, higher image quality, and better spatial and temporal resolution; functional capabilities including fMRI and DTI; non-rigid registration algorithms to register pre- and intraoperative images; non-MRI imaging improvements to continuously monitor brain shift to identify when a new 3D MRI data set is needed intraoperatively; more integration of imaging and MRI-compatible navigational and robot-assisted systems; and greater computational capabilities to handle the processing of data. The Brigham and Women’s Hospital’s “AMIGO” suite is described as a setting for progress to continue in ioMRI by incorporating other modalities including molecular imaging. A call to action is made to have other researchers and clinicians in the field of image guided therapy to work together to integrate imaging with therapy delivery systems (such as laser, MRgFUS, endoscopic, and robotic surgery devices). PMID:20960316

  18. Intraoperative wake-up test in neonatal neurosurgery.

    PubMed

    Govindarajan, Ramasamy; Babalola, Oluwaseun; Gad-El-Kareem, Magdy; Kodali, Nagendra S; Aronson, Judith; Abadir, Adel

    2006-04-01

    Intraoperative wake-up test (WPT) still remains the gold standard to monitor anterior spinal cord function during spinal surgery. However, the test requires patient cooperation and hence difficult to perform in very young children or mentally challenged. In this report, we describe a WPT in a newborn during surgical repair of a large myelomeningocele. We relied on mivacurium for intubation and the relaxant effect was allowed to wear-off to permit the use of intraoperative nerve stimulator. We used desflurane and propofol infusion for rapid titration of the anesthetic depth and BIS monitor to 'gauge' the 'wakefulness' of the child during the WPT. We employed lidocaine infusion to improve tolerance to the tracheal tube and to bestow beneficial effect on intracranial pressure during surgery and the WPT. The results of the WPT were judged to be satisfactory after confirming flexion and extension of the lower extremities at the hip and knee level, correlating it with the BIS values, and comparing it with the preoperative status. Frequently associated prematurity, higher possibility of remaining intubated in the immediate postoperative period and any new onset neurologic deficit not becoming apparent until after extubation makes intraoperative neuromonitoring relevant in this age group. Our methodology of management has permitted us to perform a delicate test safely and will allow us to repeat the WPT if needed during neonatal neurosurgery. PMID:16618301

  19. [Clinical research of intraoperative floppy iris syndrome during operation].

    PubMed

    Sun, Bing; Sun, Si-qin; Wen, Yue-chun; Liao, Rong-feng

    2008-12-01

    Intraoperative floppy iris syndrome (IFIS) has been recently identified as a new small pupil syndrome during phacoemulsification. This syndrome is characterized by three intraoperative features: a flaccid iris stroma that undulates and bellows in response to intraocular fluid currents; a propensity for the floppy iris stroma to prolapse toward the tip of phacoemulsification and side-port incisions despite proper wound construction; and progressive intraoperative pupil constriction despite standard preventive preoperative pharmacologic measures designed to prevent this. It is now mostly considered that IFIS is associated with the use of tamsolusin, a highly selective alpha-1A receptor antagonist for the treatment of benign prostatic hypertrophy. It is recommended that a careful history of the use of alpha-1 blocking agents be taken before cataract surgery to anticipate the occurrence of IFIS. A combination of strategies could decrease the complications of IFIS. These procedures include preoperative use of atropine, intracameral injection of dilute phenylephrine or epinephrine, the use of super-cohesive ophthalmic viscosurgical devices, lower phacoemulsification vacuum and aspiration settings and various iris hooks or pupil dilators. PMID:19187677

  20. Intraoperative augmented reality for minimally invasive liver interventions

    NASA Astrophysics Data System (ADS)

    Scheuering, Michael; Schenk, Andrea; Schneider, Armin; Preim, Bernhard; Greiner, Guenther

    2003-05-01

    Minimally invasive liver interventions demand a lot of experience due to the limited access to the field of operation. In particular, the correct placement of the trocar and the navigation within the patient's body are hampered. In this work, we present an intraoperative augmented reality system (IARS) that directly projects preoperatively planned information and structures extracted from CT data, onto the real laparoscopic video images. Our system consists of a preoperative planning tool for liver surgery and an intraoperative real time visualization component. The planning software takes into account the individual anatomy of the intrahepatic vessels and determines the vascular territories. Methods for fast segmentation of the liver parenchyma, of the intrahepatic vessels and of liver lesions are provided. In addition, very efficient algorithms for skeletonization and vascular analysis allowing the approximation of patient-individual liver vascular territories are included. The intraoperative visualization is based on a standard graphics adapter for hardware accelerated high performance direct volume rendering. The preoperative CT data is rigidly registered to the patient position by the use of fiducials that are attached to the patient's body, and anatomical landmarks in combination with an electro-magnetic navigation system. Our system was evaluated in vivo during a minimally invasive intervention simulation in a swine under anesthesia.

  1. Intraoperative echocardiographic detection of regurgitant jets after valve replacement

    NASA Technical Reports Server (NTRS)

    Morehead, A. J.; Firstenberg, M. S.; Shiota, T.; Qin, J.; Armstrong, G.; Cosgrove, D. M. 3rd; Thomas, J. D.

    2000-01-01

    BACKGROUND: Paravalvular jets, documented by intraoperative transesophageal echocardiography, have prompted immediate valve explantation by others, yet the significance of these jets is unknown. METHODS: Twenty-seven patients had intraoperative transesophageal two-dimensional color Doppler echocardiography, performed to assess the number and area of regurgitant jets after valve replacement, before and after protamine. Patients were grouped by first time versus redo operation, valve position and type. RESULTS: Before protamine, 55 jets were identified (2.04+/-1.4 per patient) versus 29 jets after (1.07+/-1.2 per patient, p = 0.0002). Total jet area improved from 2.0+/-2.2 cm2 to 0.86+/-1.7 cm2 with protamine (p<0.0001). In all patients jet area decreased (average decrease, 70.7%+/-27.0%). First time and redo operations had similar improvements in jet number and area (both p>0.6). Furthermore, mitral and mechanical valves each had more jets and overall greater jet area when compared to aortic and tissue valves, respectively. CONCLUSIONS: Following valve replacement, multiple jets are detected by intraoperative transesophageal echocardiography. They are more common and larger in the mitral position and with mechanical valves. Improvement occurs with reversal of anticoagulation.

  2. A New Measure for Monitoring Intraoperative Somatosensory Evoked Potentials

    PubMed Central

    Jin, Seung-Hyun; Kim, Jeong Eun; Choi, Young Doo

    2014-01-01

    Objective To propose a new measure for effective monitoring of intraoperative somatosensory evoked potentials (SEP) and to validate the feasibility of this measure for evoked potentials (EP) and single trials with a retrospective data analysis study. Methods The proposed new measure (hereafter, a slope-measure) was defined as the relative slope of the amplitude and latency at each EP peak compared to the baseline value, which is sensitive to the change in the amplitude and latency simultaneously. We used the slope-measure for EP and single trials and compared the significant change detection time with that of the conventional peak-to-peak method. When applied to single trials, each single trial signal was processed with optimal filters before using the slope-measure. In this retrospective data analysis, 7 patients who underwent cerebral aneurysm clipping surgery for unruptured aneurysm middle cerebral artery (MCA) bifurcation were included. Results We found that this simple slope-measure has a detection time that is as early or earlier than that of the conventional method; furthermore, using the slope-measure in optimally filtered single trials provides warning signs earlier than that of the conventional method during MCA clipping surgery. Conclusion Our results have confirmed the feasibility of the slope-measure for intraoperative SEP monitoring. This is a novel study that provides a useful measure for either EP or single trials in intraoperative SEP monitoring. PMID:25628803

  3. Global warming from HFC

    SciTech Connect

    Johnson, E.

    1998-11-01

    Using a variety of public sources, a computer model of hydrofluorocarbon (HFC) refrigerant emissions in the UK has been developed. This model has been used to estimate and project emissions in 2010 under three types of scenarios: (1) business as usual; (2) voluntary agreements to reduce refrigerant leakage; and (3) comprehensive regulations to reduce refrigerant leakage. This resulting forecast is that UK emissions of HFC refrigerants in 2010 will account for 2% to 4% of the UK`s 1990 baseline global warming contribution.

  4. Is Global Warming Accelerating?

    NASA Astrophysics Data System (ADS)

    Shukla, J.; Delsole, T. M.; Tippett, M. K.

    2009-12-01

    A global pattern that fluctuates naturally on decadal time scales is identified in climate simulations and observations. This newly discovered component, called the Global Multidecadal Oscillation (GMO), is related to the Atlantic Meridional Oscillation and shown to account for a substantial fraction of decadal fluctuations in the observed global average sea surface temperature. IPCC-class climate models generally underestimate the variance of the GMO, and hence underestimate the decadal fluctuations due to this component of natural variability. Decomposing observed sea surface temperature into a component due to anthropogenic and natural radiative forcing plus the GMO, reveals that most multidecadal fluctuations in the observed global average sea surface temperature can be accounted for by these two components alone. The fact that the GMO varies naturally on multidecadal time scales implies that it can be predicted with some skill on decadal time scales, which provides a scientific rationale for decadal predictions. Furthermore, the GMO is shown to account for about half of the warming in the last 25 years and hence a substantial fraction of the recent acceleration in the rate of increase in global average sea surface temperature. Nevertheless, in terms of the global average “well-observed” sea surface temperature, the GMO can account for only about 0.1° C in transient, decadal-scale fluctuations, not the century-long 1° C warming that has been observed during the twentieth century.

  5. Prospective evaluation of the utility of intraoperative confocal laser endomicroscopy in patients with brain neoplasms using fluorescein sodium: experience with 74 cases.

    PubMed

    Martirosyan, Nikolay L; Eschbacher, Jennifer M; Kalani, M Yashar S; Turner, Jay D; Belykh, Evgenii; Spetzler, Robert F; Nakaji, Peter; Preul, Mark C

    2016-03-01

    OBJECTIVE This study evaluated the utility, specificity, and sensitivity of intraoperative confocal laser endomicroscopy (CLE) to provide diagnostic information during resection of human brain tumors. METHODS CLE imaging was used in the resection of intracranial neoplasms in 74 consecutive patients (31 male; mean age 47.5 years; sequential 10-month study period). Intraoperative in vivo and ex vivo CLE was performed after intravenous injection of fluorescein sodium (FNa). Tissue samples from CLE imaging-matched areas were acquired for comparison with routine histological analysis (frozen and permanent sections). CLE images were classified as diagnostic or nondiagnostic. The specificities and sensitivities of CLE and frozen sections for gliomas and meningiomas were calculated using permanent histological sections as the standard. RESULTS CLE images were obtained for each patient. The mean duration of intraoperative CLE system use was 15.7 minutes (range 3-73 minutes). A total of 20,734 CLE images were correlated with 267 biopsy specimens (mean number of images/biopsy location, in vivo 84, ex vivo 70). CLE images were diagnostic for 45.98% in vivo and 52.97% ex vivo specimens. After initiation of CLE, an average of 14 in vivo images and 7 ex vivo images were acquired before identification of a first diagnostic image. CLE specificity and sensitivity were, respectively, 94% and 91% for gliomas and 93% and 97% for meningiomas. CONCLUSIONS CLE with FNa provided intraoperative histological information during brain tumor removal. Specificities and sensitivities of CLE for gliomas and meningiomas were comparable to those for frozen sections. These data suggest that CLE could allow the interactive identification of tumor areas, substantially improving intraoperative decisions during the resection of brain tumors. PMID:26926051

  6. Validation of a novel robotic telepathology platform for neuropathology intraoperative touch preparations

    PubMed Central

    Thrall, Michael J.; Rivera, Andreana L.; Takei, Hidehiro; Powell, Suzanne Z.

    2014-01-01

    Background: Robotic telepathology (RT) allows a remote pathologist to control and view a glass slide over the internet. This technology has been demonstrated to be effective on several platforms, but we present the first report on the validation of RT using the iScan Coreo Au whole slide imaging scanner. Methods: One intraoperative touch preparation slide from each of 100 cases were examined twice (200 total cases) using glass slides and RT, with a 3 week washout period between viewings, on two different scanners at two remote sites. This included 75 consecutive neuropathology cases and 25 consecutive general surgical pathology cases. Interpretations were compared using intraobserver variability. Results: Of the 200 total cases, one failed on RT. There were 47 total interpretive variances. Most of these were the result of less specific interpretations or an inability to identify scant diagnostic material on RT. Nine interpretive variances had potentially significant clinical implications (4.5%). Using the final diagnosis as a basis for comparison to evaluate these nine cases, three RT interpretations and three glass slide interpretations were considered to be discrepant. In the other three cases, both modalities were discrepant. This distribution of discrepancies indicates that underlying case difficulty, not the RT technology, probably accounts for these major variances. For the subset of 68 neoplastic neuropathology cases, the unweighted kappa of agreement between glass slides and RT was 0.68 (good agreement). RT took 225 s on average versus only 71 s per glass slide. Conclusions: This validation demonstrates that RT using the iScan Coreo Au system is a reasonable method for supplying remote neuropathology expertise for the intraoperative interpretation of touch preparations, but is limited by the slowness of the robotics, crude focusing, and the challenge of determining where to examine the slide using small thumbnail images. PMID:25191620

  7. Case report: Recurrent glossopharyngeal neuralgia after previous glossopharyngeal rhizotomy: Microvascular decompression with intra-operative neurophysiology.

    PubMed

    Price, Sally-Ann S; Davies, Owain; Walsh, Peter; Patel, Nikunj

    2015-12-01

    We present a case of recurrent vago-glossopharyngeal neuralgia after previous surgery, treated successfully with microvascular decompression using intra-operative neurophysiology monitoring. PMID:25958960

  8. RHIC warm-bore systems

    SciTech Connect

    Welch, K.M.

    1994-07-01

    Pressure profiles, in time, are calculated as a consequence of anticipated outgassing of various beam components (e.g., rf cavities, etc.) and warm-bore beam pipes. Gold beam lifetimes and transverse beam emittance growth are given for calculated average pressures. Examples of undesirable warm-bore conditions are presented such as contaminated experimental beam pipes and warm-bore magnets (i.e., DX). These examples may prove instructive. The methods used in making these calculations are presented in Section 2. They are applicable to all linear systems. The calculations given apply to the RHIC accelerator and more specifically to warm-bore regions of the machine.

  9. Benefit and accuracy of intraoperative 3D-imaging after pedicle screw placement: a prospective study in stabilizing thoracolumbar fractures

    PubMed Central

    Mittlmeier, Thomas; Gierer, Philip; Harms, Christoph; Gradl, Georg

    2009-01-01

    Internal fixation is the established dorsal standard procedure for the treatment of thoracolumbar fractures. The main problem of the procedure is the false positioning of the pedicle screws. The exact determination of pedicle screws has up to now only been possible through postoperative computed tomography. This study was intended to clarify the diagnostic value of intraoperative 3D scans after pedicle screw implantation in thoracolumbar spine surgery. The direct intraoperative consequences of the 3D scans are reported and the results of the 3D scans are compared with the postoperative computed tomography images. Intraoperative 3D scans were prospectively carried out from June 2006 to October 2008 on 95 patients with fractures of the thoracolumbar spine that have been treated with internal fixation. Screws positions were categorised intraoperatively, screws in relevant malposition were repositioned immediately. A computed tomography of the involved spinal section was carried out postoperatively for all patients. The positions of the pedicle screws were determined and compared in the axial reconstructions of both procedures. Four hundred and fourteen pedicles with enclosed screws were evaluated by the 3D scans. The time needed for carrying out the 3D scan amounts to an average of 8.2min. Eleven screws (2.7%) in ten patients were primarily intraoperatively repositioned on the basis of the 3D scan evaluation. Two of 95 patients had to have false positions of the screws revised secondarily following evaluation of the computed tomographies. The secondary postoperative revision rate of the patients amounts to 2.1%. In relation to the number of screws, this is a revision rate of 0.5%. The postoperative computed tomographies showed 323 pedicles without cortical penetration by the screws (78.0%). Ninety-one screws penetrated the pedicle wall (22%). It was possible to postoperatively compare the position classifications of 406 pedicle screws. The CT showed 378 correct screw positions, while 28 screws were positioned falsely. On the basis of the 3D scans, 376 of 378 correct positions were correctly assessed. Twenty-one of 28 false positions could be correctly classified. The sensitivity of all 3D scans reached 91.3% and the specificity 98.2%. The position of 97.8% of the pedicle screws was correctly recognised by the intraoperative 3D scan. Nine screws were classified falsely (2.2%). The comparison of the classification results showed significantly higher error findings by the 3D scan in the spinal section T110 (P=0.014). The image quality of the 3D scan correlates significantly with the width of the scanned pedicle, with the body mass index, the scanned spinal section and the extent of the fixation assembly. 3D scans showed a high accuracy in predicting pedicle screw position. Primary false placement of screws and primary neurovascular damage cannot be avoided. But intraoperative evaluation of the 3D scans resulted in a primary revision rate of 2.7% of the pedicle screws and we could lower the secondary revision rate to 0.5%. PMID:19513764

  10. Global Warming on Triton

    NASA Technical Reports Server (NTRS)

    Elliot, J. L.; Hammel, H. B.; Wasserman, L. H.; Franz, O. G.; McDonald, S. W.; Person, M. J.; Olkin, C. B.; Dunham, E. J.; Spencer, J. R.; Stansberry, J. A.; Buie, M. W.; Pasachoff, J. M.; Babcock, B. A.; McConnochie, T. H.

    1998-01-01

    Triton, Neptune's largest moon, has been predicted to undergo significant seasonal changes that would reveal themselves as changes in its mean frost temperature. But whether this temperature should at the present time be increasing, decreasing or constant depends on a number of parameters (such as the thermal properties of the surface, and frost migration patterns) that are unknown. Here we report observations of a recent stellar occultation by Triton which, when combined with earlier results, show that Triton has undergone a period of global warming since 1989. Our most conservative estimates of the rate of temperature and surface-pressure increase during this period imply that the atmosphere is doubling in bulk every 10 years, significantly faster than predicted by any published frost model for Triton. Our result suggests that permanent polar caps on Triton play a c dominant role in regulating seasonal atmospheric changes. Similar processes should also be active on Pluto.

  11. Global warming challenge

    SciTech Connect

    Hengeveld, H. )

    1994-11-01

    Global warming will necessitate significant adjustments in Canadian society and its economy. In 1979, the Canadian federal government created its Canadian Climate Program (CCP) in collaboration with other agencies, institutions, and individuals. It sought to coordinate national efforts to understand global and regional climate, and to promote better use of the emerging knowledge. Much of the CCP-coordinated research into sources and sinks of greenhouse gases interfaces with other national and international programs. Other researchers have become involved in the Northern Wetlands Study, a cooperative United States-Canada initiative to understand the role of huge northern bogs and muskegs in the carbon cycle. Because of the need to understand how the whole, linked climate system works, climate modeling emerged as a key focus of current research. 35 refs., 4 figs.

  12. Warm waters, bleached corals

    SciTech Connect

    Roberts, L.

    1990-10-12

    Two researchers, Tom Goreau of the Discovery Laboratory in Jamaica and Raymond Hayes of Howard University, claim that they have evidence that nearly clinches the temperature connection to the bleached corals in the Caribbean and that the coral bleaching is an indication of Greenhouse warming. The incidents of scattered bleaching of corals, which have been reported for decades, are increasing in both intensity and frequency. The researchers based their theory on increased temperature of the seas measured by satellites. However, some other scientists feel that the satellites measure the temperature of only the top few millimeters of the water and that since corals lie on reefs perhaps 60 to 100 feet below the ocean surface, the elevated temperatures are not significant.

  13. Interacting warm dark matter

    SciTech Connect

    Cruz, Norman; Palma, Guillermo; Zambrano, David; Avelino, Arturo E-mail: guillermo.palma@usach.cl E-mail: avelino@fisica.ugto.mx

    2013-05-01

    We explore a cosmological model composed by a dark matter fluid interacting with a dark energy fluid. The interaction term has the non-linear λρ{sub m}{sup α}ρ{sub e}{sup β} form, where ρ{sub m} and ρ{sub e} are the energy densities of the dark matter and dark energy, respectively. The parameters α and β are in principle not constrained to take any particular values, and were estimated from observations. We perform an analytical study of the evolution equations, finding the fixed points and their stability properties in order to characterize suitable physical regions in the phase space of the dark matter and dark energy densities. The constants (λ,α,β) as well as w{sub m} and w{sub e} of the EoS of dark matter and dark energy respectively, were estimated using the cosmological observations of the type Ia supernovae and the Hubble expansion rate H(z) data sets. We find that the best estimated values for the free parameters of the model correspond to a warm dark matter interacting with a phantom dark energy component, with a well goodness-of-fit to data. However, using the Bayesian Information Criterion (BIC) we find that this model is overcame by a warm dark matter – phantom dark energy model without interaction, as well as by the ΛCDM model. We find also a large dispersion on the best estimated values of the (λ,α,β) parameters, so even if we are not able to set strong constraints on their values, given the goodness-of-fit to data of the model, we find that a large variety of theirs values are well compatible with the observational data used.

  14. Local warming: daily temperature change influences belief in global warming.

    PubMed

    Li, Ye; Johnson, Eric J; Zaval, Lisa

    2011-04-01

    Although people are quite aware of global warming, their beliefs about it may be malleable; specifically, their beliefs may be constructed in response to questions about global warming. Beliefs may reflect irrelevant but salient information, such as the current day's temperature. This replacement of a more complex, less easily accessed judgment with a simple, more accessible one is known as attribute substitution. In three studies, we asked residents of the United States and Australia to report their opinions about global warming and whether the temperature on the day of the study was warmer or cooler than usual. Respondents who thought that day was warmer than usual believed more in and had greater concern about global warming than did respondents who thought that day was colder than usual. They also donated more money to a global-warming charity if they thought that day seemed warmer than usual. We used instrumental variable regression to rule out some alternative explanations. PMID:21372325

  15. Intraoperative photodynamic therapy in laryngeal part of pharynx cancers

    NASA Astrophysics Data System (ADS)

    Loukatch, Erwin V.; Trojan, Vasily; Loukatch, Vjacheslav

    1996-12-01

    In clinic intraoperative photodynamic therapy (IPT) was done in patients with primal squamous cells cancer of the laryngeal part of the pharynx. The He-Ne laser and methylene blue as a photosensibilizator were used. Cobalt therapy in the postoperative period was done in dose 45 Gr. Patients of control groups (1-th group) with only laser and (2-th group) only methylene blue were controlled during three years with the main group. The statistics show certain differences of recidives in the main group compared to the control groups. These facts are allowing us to recommend the use of IPT as an additional method in ENT-oncology diseases treatment.

  16. Necrotizing Fasciitis: A Life-threatening Complication of Intraoperative Electromyography.

    PubMed

    Shoakazemi, Alireza; Moisi, Marc; Tubbs, R Shane; Wingerson, Mary; Ajayi, Olaide; Zwillman, Michael E; Gottlieb, Jourdan; Hanscom, David

    2016-01-01

    Intraoperative neurophysiological monitoring is a commonly used practice during spine surgery. Complications of electromyography (EMG) needle electrode placement are very uncommon. We present a patient who was infected with necrotizing fasciitis in her left thigh due to an EMG needle electrode during a two-stage complex spine procedure. This case demonstrates that providers should continue to meticulously adhere to protocol when inserting and removing EMG needles, but also be cognizant during postoperative observation of the possibility of infection caused by EMG needles. PMID:26973803

  17. Intraoperative Optical Imaging and Tissue Interrogation During Urologic Surgery

    PubMed Central

    Hsu, Mark; Gupta, Mohit; Su, Li-Ming; Liao, Joseph C.

    2014-01-01

    Purpose of review To review optical imaging technologies in urologic surgery aimed to facilitate intraoperative imaging and tissue interrogation. Recent findings Emerging new optical imaging technologies can be integrated in the operating room environment during minimally invasive and open surgery. These technologies include macroscopic fluorescence imaging that provides contrast enhancement between normal and diseased tissue and microscopic imaging that provides tissue characterization. Summary Optical imaging technologies that have reached the clinical arena in urologic surgery are reviewed, including photodynamic diagnosis, near infrared fluorescence imaging, optical coherence tomography, and confocal laser endomicroscopy. PMID:24240512

  18. [Importance of preoperative and intraoperative imaging for operative strategies].

    PubMed

    Nitschke, P; Bork, U; Plodeck, V; Podlesek, D; Sobottka, S B; Schackert, G; Weitz, J; Kirsch, M

    2016-03-01

    Recent advances in preoperative and postoperative imaging have an increasing influence on surgical decision-making and make more complex surgical interventions possible. This improves the possibilities for frequently occurring challenges and promoting improved functional and oncological outcome. This manuscript reviews the role of preoperative and intraoperative imaging in surgery. Various techniques are explained based on examples from hepatobiliary surgery and neurosurgery, in particular real-time procedures, such as the online use of augmented reality and in vivo fluorescence, as well as new and promising optical techniques including imaging of intrinsic signals and vibrational spectroscopy. PMID:26939896

  19. Intraoperative spectral domain optical coherence tomography for vitreoretinal surgery

    PubMed Central

    Tao, Yuankai K.; Ehlers, Justis P.; Toth, Cynthia A.; Izatt, Joseph A.

    2011-01-01

    We demonstrate in vivo human retinal imaging using an intraoperative microscope-mounted optical coherence tomography system (MMOCT). Our optomechanical design adapts an Oculus Binocular Indirect Ophthalmo Microscope (BIOM3), suspended from a Leica ophthalmic surgical microscope, with spectral domain optical coherence tomography (SD-OCT) scanning and relay optics. The MMOCT enables wide-field noncontact real-time cross-sectional imaging of retinal structure, allowing for SD-OCT augmented intrasurgical microscopy for intraocular visualization. We experimentally quantify the axial and lateral resolution of the MMOCT and demonstrate fundus imaging at a 20 Hz frame rate. PMID:20967051

  20. Policy implications of greenhouse warming

    NASA Astrophysics Data System (ADS)

    Coppock, Rob

    1992-03-01

    A study panel of the National Academy of Sciences, National Academy of Engineering, and Institute of Medicine recently issued the report Policy Implications of Greenhouse Warming. That report examined relevant scientific knowldeg and evidence about the potential of greenhouse warming, and assayed actions that could slow the onset of warming (mitigation policies) or help human and natural systems of plants and animals adapt to climatic changes (adaptation policies). The panel found that, even given the considerable uncertainties knowledge of the relevant phenomena, greenhouse warming poses a threat sufficient to merit prompt action. People in this country could probably adapt to the changes likely to accompany greenhouse warming. The costs, however, could be substantial. Investment in mitigation acts as insurance protection against the great uncertainties and the possibility of dramatic surprises. The panel found mitigation options that could reduce U.S. emissions by an estimated 10 to 40 percent at modest cost.

  1. Feasibility assessment of the interactive use of a Monte Carlo algorithm in treatment planning for intraoperative electron radiation therapy.

    PubMed

    Guerra, Pedro; Udías, José M; Herranz, Elena; Santos-Miranda, Juan Antonio; Herraiz, Joaquín L; Valdivieso, Manlio F; Rodríguez, Raúl; Calama, Juan A; Pascau, Javier; Calvo, Felipe A; Illana, Carlos; Ledesma-Carbayo, María J; Santos, Andrés

    2014-12-01

    This work analysed the feasibility of using a fast, customized Monte Carlo (MC) method to perform accurate computation of dose distributions during pre- and intraplanning of intraoperative electron radiation therapy (IOERT) procedures. The MC method that was implemented, which has been integrated into a specific innovative simulation and planning tool, is able to simulate the fate of thousands of particles per second, and it was the aim of this work to determine the level of interactivity that could be achieved. The planning workflow enabled calibration of the imaging and treatment equipment, as well as manipulation of the surgical frame and insertion of the protection shields around the organs at risk and other beam modifiers. In this way, the multidisciplinary team involved in IOERT has all the tools necessary to perform complex MC dosage simulations adapted to their equipment in an efficient and transparent way. To assess the accuracy and reliability of this MC technique, dose distributions for a monoenergetic source were compared with those obtained using a general-purpose software package used widely in medical physics applications. Once accuracy of the underlying simulator was confirmed, a clinical accelerator was modelled and experimental measurements in water were conducted. A comparison was made with the output from the simulator to identify the conditions under which accurate dose estimations could be obtained in less than 3 min, which is the threshold imposed to allow for interactive use of the tool in treatment planning. Finally, a clinically relevant scenario, namely early-stage breast cancer treatment, was simulated with pre- and intraoperative volumes to verify that it was feasible to use the MC tool intraoperatively and to adjust dose delivery based on the simulation output, without compromising accuracy. The workflow provided a satisfactory model of the treatment head and the imaging system, enabling proper configuration of the treatment planning system and providing good accuracy in the dosage simulation. PMID:25365625

  2. Feasibility assessment of the interactive use of a Monte Carlo algorithm in treatment planning for intraoperative electron radiation therapy

    NASA Astrophysics Data System (ADS)

    Guerra, Pedro; Udías, José M.; Herranz, Elena; Santos-Miranda, Juan Antonio; Herraiz, Joaquín L.; Valdivieso, Manlio F.; Rodríguez, Raúl; Calama, Juan A.; Pascau, Javier; Calvo, Felipe A.; Illana, Carlos; Ledesma-Carbayo, María J.; Santos, Andrés

    2014-12-01

    This work analysed the feasibility of using a fast, customized Monte Carlo (MC) method to perform accurate computation of dose distributions during pre- and intraplanning of intraoperative electron radiation therapy (IOERT) procedures. The MC method that was implemented, which has been integrated into a specific innovative simulation and planning tool, is able to simulate the fate of thousands of particles per second, and it was the aim of this work to determine the level of interactivity that could be achieved. The planning workflow enabled calibration of the imaging and treatment equipment, as well as manipulation of the surgical frame and insertion of the protection shields around the organs at risk and other beam modifiers. In this way, the multidisciplinary team involved in IOERT has all the tools necessary to perform complex MC dosage simulations adapted to their equipment in an efficient and transparent way. To assess the accuracy and reliability of this MC technique, dose distributions for a monoenergetic source were compared with those obtained using a general-purpose software package used widely in medical physics applications. Once accuracy of the underlying simulator was confirmed, a clinical accelerator was modelled and experimental measurements in water were conducted. A comparison was made with the output from the simulator to identify the conditions under which accurate dose estimations could be obtained in less than 3 min, which is the threshold imposed to allow for interactive use of the tool in treatment planning. Finally, a clinically relevant scenario, namely early-stage breast cancer treatment, was simulated with pre- and intraoperative volumes to verify that it was feasible to use the MC tool intraoperatively and to adjust dose delivery based on the simulation output, without compromising accuracy. The workflow provided a satisfactory model of the treatment head and the imaging system, enabling proper configuration of the treatment planning system and providing good accuracy in the dosage simulation.

  3. Autophagic activation in vitrified-warmed mouse oocytes.

    PubMed

    Bang, Soyoung; Shin, Hyejin; Song, Haengseok; Suh, Chang Suk; Lim, Hyunjung Jade

    2014-07-01

    Vitrification involves the use of cryoprotectants (CPAs) and liquid nitrogen (LN2), which may cause osmotic damage and cryoinjury to oocytes. Autophagy is widely recognized as a survival or response mechanism elicited by various environmental and cellular stressors. However, the induction of autophagy in vitrified-warmed oocytes has not been examined. In this work, we investigated whether the vitrification-warming process induces autophagy in mouse oocytes. Metaphase II (MII) oocytes that were vitrified and stored in LN2 for at least 2 weeks were used in the study. In RT-PCR analyses, we observed that several Atg genes such as Atg5, Atg7, Atg12, LC3a (Map1lc3a), LC3b (Map1lc3b), and Beclin1 were expressed in MII mouse oocytes. Slight reduction in mRNA levels of Atg7 and Atg12 in vitrified-warmed oocytes was noted, and expression of these genes was not significantly influenced. Confocal live imaging analysis using oocytes from GFP-LC3 transgenic mice revealed that vitrified-warmed oocytes had a significantly higher number of GFP-LC3 puncta in comparison to fresh oocytes. The expression of BECLIN1 protein was also increased in vitrified-warmed oocytes. Treatment with 3-methyladenine, an inhibitor of autophagy, did not significantly affect the rates of oocyte survival, IVF, and embryonic development after warming and IVF. The results suggest that the observed autophagic activation in vitrified-warmed oocytes is a natural adaptive response to cold stress. Collectively, we show for the first time that vitrified-warmed mouse oocytes exhibit autophagic activation during warming and that this response is not induced by CPA-containing solutions. The induction of autophagy by cold temperature is first reported herein. PMID:24760879

  4. Histopathological and biochemical effects of intraoperative interstitial radiofrequency-induced hyperthermia and intraoperative electron radiation, alone and in combination, on normal canine liver tissue

    SciTech Connect

    Williford, K.J.

    1988-01-01

    Acute and chronic histopathologic and biochemical effects on normal canine liver tissue from a single intraoperative application of heat and radiation, heat alone, and radiation alone have been evaluated in 54 adult mongrel dogs. The tolerance of normal canine liver tissue to single doses of intraoperative radiation therapy (IORT) was evaluated at doses of 5, 10, 20, 30, and 40 Gy. In addition, intraoperative interstitial hyperthermia (43{degree}C, 60 minutes, 500 kHz) was applied alone and in combination with a single intraoperative dose of 30 Gy from an 18 MeV electron beam. Blood flow at the center of the implantation site before, during and after hyperthermia treatments was also evaluated.

  5. Toward Microendoscopic Electrical Impedance Tomography for Intraoperative Surgical Margin Assessment

    PubMed Central

    Halter, Ryan J.; Kim, Young-Joong

    2015-01-01

    No clinical protocols are routinely used to intraoperatively assess surgical margin status during prostate surgery. Instead, margins are evaluated through pathological assessment of the prostate following radical prostatectomy, when it is too late to provide additional surgical intervention. An intraoperative device potentially capable of assessing surgical margin status based on the electrical property contrast between benign and malignant prostate tissue has been developed. Specifically, a microendoscopic electrical impedance tomography (EIT) probe has been constructed to sense and image, at near millimeter resolution, the conductivity contrast within heterogeneous biological tissues with the goal of providing surgeons with real-time assessment of margin pathologies. This device consists of a ring of eight 0.6-mm diameter electrodes embedded in a 5-mm diameter probe tip to enable access through a 12-mm laparoscopic port. Experiments were performed to evaluate the volume of tissue sensed by the probe. The probe was also tested with inclusions in gelatin, as well as on a sample of porcine tissue with clearly defined regions of adipose and muscle. The probe's area of sensitivity consists of a circular area of 9.1 mm2 and the maximum depth of sensitivity is approximately 1.5 mm. The probe is able to distinguish between high contrast muscle and adipose tissue on a sub-mm scale (~500 μm). These preliminary results suggest that EIT is possible in a probe designed to fit within a 12-mm laparoscopic access port. PMID:24951675

  6. Intraoperative radiotherapy in stage I and II lung cancer

    SciTech Connect

    Hilaris, B.S.; Nori, D.; Martini, N.

    1987-01-01

    Lung cancer is the leading cause of cancer deaths in both men and women in the United States. Treatment depends on the type and stage of lung cancer. For stage I and II cancer, surgery is usually the treatment of choice. Radiation therapy is used in patients who are considered poor risks for surgical resection. Intraoperative brachytherapy is an effective alternative to external irradiation in this group of patients. From 1958 to 1984, 55 patients with non-small-cell lung cancer were explored at Memorial Sloan Kettering Cancer Center and found to have surgical stage I or II tumors, which were considered to be unresectable mainly because of severe obstructive pulmonary disease precluding adequate resection. All these patients were treated with intraoperative brachytherapy at the time of the thoracotomy. Forty-four percent of these patients received in addition external irradiation, mainly to the mediastinum. The overall 5-year survival calculated by the Kaplan-Meier Method was 32%, and the local disease-free survival was 63%. Cox regression multivariant analysis demonstrated that there is a distinct subgroup with a better prognosis based on tumor site and patient's age--ie, patients who were younger than 58 years of age and had right-side lesions.

  7. Floating the uvula: an intraoperative method for detecting bifidity.

    PubMed

    Suryadevara, Amar C; Tatum, Sherard A

    2007-01-01

    A bifid uvula, midline diastasis of the palatal muscles, and notching of the posterior hard palate have classically formed a triad diagnosing submucosal clefts. The uvula has thus served as a tool for clinicians to detect the earliest signs of clefting. In this case report, we discuss how mucosal lining may be held together by mucous viscosity, making it difficult to detect notching or a grossly bifid uvula. We demonstrate a simple intraoperative technique to easily overcome this force. This paper involves a case report of an 8-year-old female undergoing an adenotonsillectomy. A previously undetected bifid uvula was found only after floating the uvula in normal saline solution. This changed our surgical approach from a complete to a partial adenoidectomy. A bifid uvula may be considered the earliest form of a cleft palate, and more importantly, it has been shown in the literature to be associated with other anomalies as submucosal cleft, hyoplastic eustachian tube orifice, and absence of the salpingopharyngeal folds. The intraoperative technique of floating the uvula helps to overcome mucous viscosity and identify an otherwise missed bifid uvula. PMID:17049625

  8. Problem of intraoperative anatomical shift in image-guided surgery

    NASA Astrophysics Data System (ADS)

    Nauta, Haring J.; Bonnen, J. G.

    1998-06-01

    Experience with image guided, frameless stereotactic neurosurgery shows that intraoperative brain position shifts can be large enough to be problematic, and can occur in different directions at different directions at different stages of an operation. An understanding of the behavior of shifts will allow the surgeon to make the most appropriate use of the image guidance by first minimizing the shift itself, and then anticipating and compensating for any influence the remaining shift will have on the accuracy of the guidance. Three types of shift are described. Type I shift is a local outward bulging that occurs after the skull and dura are opened but before a mass lesion is resected. Type II shift is a local collapse of the brain tissue into the space previously occupied by the tumor. Type III shift is related to loss of cerebrospinal fluid or brain dehydration and is a generalized, more symmetric loss of brain volume. Strategies to minimize these types of shift include appropriate use of medical measures to reduce brain swelling early in the procedure without producing so much brain dehydration that Type II shift is accentuated later in the procedure. Other strategies include mechanical stabilization of brain position with retractors. Anticipating shift, the neurosurgeon should use the guidance as far as possible to map key boundaries early in the procedure before shift becomes more pronounced. Ultimately, however, the correction for the problem of intraoperative brain shift will require the ability to update the imaging data during the surgery.

  9. Stereoscopic Integrated Imaging Goggles for Multimodal Intraoperative Image Guidance.

    PubMed

    Mela, Christopher A; Patterson, Carrie; Thompson, William K; Papay, Francis; Liu, Yang

    2015-01-01

    We have developed novel stereoscopic wearable multimodal intraoperative imaging and display systems entitled Integrated Imaging Goggles for guiding surgeries. The prototype systems offer real time stereoscopic fluorescence imaging and color reflectance imaging capacity, along with in vivo handheld microscopy and ultrasound imaging. With the Integrated Imaging Goggle, both wide-field fluorescence imaging and in vivo microscopy are provided. The real time ultrasound images can also be presented in the goggle display. Furthermore, real time goggle-to-goggle stereoscopic video sharing is demonstrated, which can greatly facilitate telemedicine. In this paper, the prototype systems are described, characterized and tested in surgeries in biological tissues ex vivo. We have found that the system can detect fluorescent targets with as low as 60 nM indocyanine green and can resolve structures down to 0.25 mm with large FOV stereoscopic imaging. The system has successfully guided simulated cancer surgeries in chicken. The Integrated Imaging Goggle is novel in 4 aspects: it is (a) the first wearable stereoscopic wide-field intraoperative fluorescence imaging and display system, (b) the first wearable system offering both large FOV and microscopic imaging simultaneously, PMID:26529249

  10. ECG artifacts during intraoperative high-field MRI scanning.

    PubMed

    Birkholz, Torsten; Schmid, Markus; Nimsky, Christopher; Schttler, Jrgen; Schmitz, Bernd

    2004-10-01

    High-field magnetic resonance imaging (MRI) (1.5 T) has recently been introduced into the neurosurgical operating room for intraoperative resection control and functional neuronavigational guidance. However, long-lasting neurosurgical procedures in an operating room equipped with a high-field MRI scanner raise new challenges to the anesthesiologist. In particular, monitoring of vital signs during anesthesia requires equipment compatible with working in close vicinity to the strong magnetic field. However, even MRI-compatible electrocardiographic (ECG) monitoring interferes with electromagnetic fields, so several ECG artifacts can be observed in static and pulsed magnetic fields. As shown in this study, pulsed high-frequency fields induce characteristic field frequency-based artifacts in the ECG that can imitate malignant arrhythmia or provoke ST-segment abnormalities. The knowledge of possible and characteristic ECG artifacts during high-field MRI is therefore essential to prevent misinterpretation. Moreover, interference-free parameters such as pulse oximetry or invasive blood pressure curves are highly relevant during intraoperative MRI scans. PMID:15557829

  11. Intraoperative Three-Dimensional Imaging in Calcaneal Fracture Treatment

    PubMed Central

    Gwak, Heui-Chul; Kim, Jung-Han; Roh, Sang-Myung

    2015-01-01

    Background To compare the effectiveness of intraoperative three-dimensional (3D) image and conventional two-dimensional (2D) fluoroscopic images, which are used in the treatment of acute calcaneal fractures. Methods We retrospectively analyzed 40 patients who suffered calcaneal fracture and underwent surgery at Inje University Busan Paik Hospital. The patients were divided into two groups. Only 2D fluoroscopy was used to evaluate 20 patients of group 1. On the other hand, 3D fluoroscopy was performed on the remaining 20 patients of group 2; 3D fluoroscopy was performed on these patients after they were extensively evaluated by 2D fluoroscopy during surgery. We reviewed the radiographic and clinical outcomes of these patients, whose average follow-up period was 42.6 months. Results In group 2, 3D fluoroscopy detected four cases (20%) of articular incongruence and screw misplacement. All these complicated cases were corrected during surgery. At the final follow-up session, the mean American Orthopedic Foot and Ankle Society (AOFAS) hind foot score was 78.3 (range, 65 to 95) in group 1 and 82.3 (range, 68 to 95) in group 2. Conclusions Intraoperative 3D imaging of calcaneal fractures is considered to be useful in evaluating the congruence of joints and the placement of implants. PMID:26640632

  12. Stereoscopic Integrated Imaging Goggles for Multimodal Intraoperative Image Guidance

    PubMed Central

    Mela, Christopher A.; Patterson, Carrie; Thompson, William K.; Papay, Francis; Liu, Yang

    2015-01-01

    We have developed novel stereoscopic wearable multimodal intraoperative imaging and display systems entitled Integrated Imaging Goggles for guiding surgeries. The prototype systems offer real time stereoscopic fluorescence imaging and color reflectance imaging capacity, along with in vivo handheld microscopy and ultrasound imaging. With the Integrated Imaging Goggle, both wide-field fluorescence imaging and in vivo microscopy are provided. The real time ultrasound images can also be presented in the goggle display. Furthermore, real time goggle-to-goggle stereoscopic video sharing is demonstrated, which can greatly facilitate telemedicine. In this paper, the prototype systems are described, characterized and tested in surgeries in biological tissues ex vivo. We have found that the system can detect fluorescent targets with as low as 60 nM indocyanine green and can resolve structures down to 0.25 mm with large FOV stereoscopic imaging. The system has successfully guided simulated cancer surgeries in chicken. The Integrated Imaging Goggle is novel in 4 aspects: it is (a) the first wearable stereoscopic wide-field intraoperative fluorescence imaging and display system, (b) the first wearable system offering both large FOV and microscopic imaging simultaneously, (c) the first wearable system that offers both ultrasound imaging and fluorescence imaging capacities, and (d) the first demonstration of goggle-to-goggle communication to share stereoscopic views for medical guidance. PMID:26529249

  13. Intraoperative Evaluation of Breast Tumor Margins with Optical Coherence Tomography

    PubMed Central

    Nguyen, Freddy T.; Zysk, Adam M.; Chaney, Eric J.; Kotynek, Jan G.; Oliphant, Uretz J.; Bellafiore, Frank J.; Rowland, Kendrith M.; Johnson, Patricia A.; Boppart, Stephen A.

    2009-01-01

    As breast cancer screening rates increase, smaller and more numerous lesions are being identified earlier, leading to more breast-conserving surgical procedures. Achieving a clean surgical margin represents a technical challenge with important clinical implications. Optical coherence tomography (OCT) is introduced as an intraoperative high-resolution imaging technique that assesses surgical breast tumor margins by providing real-time microscopic images up to 2 mm beneath the tissue surface. In a study of 37 patients split between training and study groups, OCT images covering 1 cm2 regions were acquired from surgical margins of lumpectomy specimens, registered with ink, and correlated with corresponding histological sections. A 17 patient training set used to establish standard imaging protocols and OCT evaluation criteria demonstrated that areas of higher scattering tissue with a heterogeneous pattern were indicative of tumor cells and tumor tissue, in contrast to lower scattering adipocytes found in normal breast tissue. The remaining 20 patients were enrolled into the feasibility study. Of these lumpectomy specimens, 11 were identified with a positive or close surgical margin and 9 were identified with a negative margin under OCT. Based on histological findings, 9 true positives, 9 true negatives, 2 false positives, and 0 false negatives were found, yielding a sensitivity of 100% and specificity of 82%. These results demonstrate the potential of OCT as a real-time method for intraoperative margin assessment in breast conserving surgeries. PMID:19910294

  14. Intraoperative passive knee kinematics during total knee arthroplasty surgery.

    PubMed

    Young, Kathryn L; Dunbar, Michael J; Richardson, Glen; Astephen Wilson, Janie L

    2015-11-01

    Surgical navigation systems for total knee arthroplasty (TKA) surgery are capable of capturing passive three-dimensional (3D) angular joint movement patterns intraoperatively. Improved understanding of patient-specific knee kinematic changes between pre and post-implant states and their relationship with post-operative function may be important in optimizing TKA outcomes. However, a comprehensive characterization of the variability among patients has yet to be investigated. The objective of this study was to characterize the variability within frontal plane joint movement patterns intraoperatively during a passive knee flexion exercise. Three hundred and forty patients with severe knee osteoarthritis (OA) received a primary TKA using a navigation system. Passive kinematics were captured prior to (pre-implant), and after prosthesis insertion (post-implant). Principal component analysis (PCA) was used to capture characteristic patterns of knee angle kinematics among patients, to identify potential patient subgroups based on these patterns, and to examine the subgroup-specific changes in these patterns between pre- and post-implant states. The first four extracted patterns explained 99.9% of the diversity within the frontal plane angle patterns among the patients. Post-implant, the magnitude of the frontal plane angle shifted toward a neutral mechanical axis in all phenotypes, yet subtle pattern (shape of curvature) features of the pre-implant state persisted. PMID:25990930

  15. Explaining Warm Coronal Loops

    NASA Technical Reports Server (NTRS)

    Klimchuk, James A.; Karpen, Judy T.; Patsourakos, Spiros

    2008-01-01

    One of the great mysteries of coronal physics that has come to light in the last few years is the discovery that warn (- 1 INK) coronal loops are much denser than expected for quasi-static equilibrium. Both the excess densities and relatively long lifetimes of the loops can be explained with bundles of unresolved strands that are heated impulsively to very high temperatures. Since neighboring strands are at different stages of cooling, the composite loop bundle is multi-thermal, with the distribution of temperatures depending on the details of the "nanoflare storm." Emission hotter than 2 MK is predicted, but it is not clear that such emission is always observed. We consider two possible explanations for the existence of over-dense warm loops without corresponding hot emission: (1) loops are bundles of nanoflare heated strands, but a significant fraction of the nanoflare energy takes the form of a nonthermal electron beam rather then direct plasma heating; (2) loops are bundles of strands that undergo thermal nonequilibrium that results when steady heating is sufficiently concentrated near the footpoints. We present numerical hydro simulations of both of these possibilities and explore the observational consequences, including the production of hard X-ray emission and absorption by cool material in the corona.

  16. Defining Sudden Stratospheric Warmings

    NASA Astrophysics Data System (ADS)

    Butler, Amy; Seidel, Dian; Hardiman, Steven; Butchart, Neal; Birner, Thomas; Match, Aaron

    2015-04-01

    The general form of the definition for Sudden Stratospheric Warmings (SSWs) is largely agreed to be a reversal of the temperature gradient and of the zonal circulation polewards of 60° latitude at the 10 hPa level, as developed by the World Meteorological Organization (WMO) in the 1960s and 1970s. However, the details of the definition and its calculation are ambiguous, resulting in inconsistent classifications of SSW events. These discrepancies are problematic for understanding the observed frequency and statistical relationships with SSWs, and for maintaining a robust metric with which to assess wintertime stratospheric variability in observations and climate models. To provide a basis for community-wide discussion, we examine how the SSW definition has changed over time and how sensitive the detection of SSWs is to the definition used. We argue that the general form of the SSW definition should be clarified to ensure that it serves current research and forecasting purposes, and propose possible ways to update the definition.

  17. Warm dense crystallography

    NASA Astrophysics Data System (ADS)

    Valenza, Ryan A.; Seidler, Gerald T.

    2016-03-01

    The intense femtosecond-scale pulses from x-ray free electron lasers (XFELs) are able to create and interrogate interesting states of matter characterized by long-lived nonequilibrium semicore or core electron occupancies or by the heating of dense phases via the relaxation cascade initiated by the photoelectric effect. We address here the latter case of "warm dense matter" (WDM) and investigate the observable consequences of x-ray heating of the electronic degrees of freedom in crystalline systems. We report temperature-dependent density functional theory calculations for the x-ray diffraction from crystalline LiF, graphite, diamond, and Be. We find testable, strong signatures of condensed-phase effects that emphasize the importance of wide-angle scattering to study nonequilibrium states. These results also suggest that the reorganization of the valence electron density at eV-scale temperatures presents a confounding factor to achieving atomic resolution in macromolecular serial femtosecond crystallography (SFX) studies at XFELs, as performed under the "diffract before destroy" paradigm.

  18. Intraoperative Nerve Monitoring During Nerve Decompression Surgery in the Lower Extremity.

    PubMed

    Anderson, James C; Yamasaki, Dwayne S

    2016-04-01

    This article describes the benefits of intraoperative neurophysiologic monitoring (IONM) and proposes methods for integration into nerve decompression procedures. Standard procedures for intraoperative nerve monitoring (IONM) are illustrated as they would apply to the 3 nerve tunnels that have significant motor components within the lower extremity. PMID:27013416

  19. Shyness Trajectories in Slow-to-Warm-Up Infants: Relations with Child Sex and Maternal Parenting

    ERIC Educational Resources Information Center

    Grady, Jessica Stoltzfus; Karraker, Katherine; Metzger, Aaron

    2012-01-01

    Little is known about slow-to-warm-up temperament in infancy. This study examined the trajectory of shyness in children who were slow-to-warm-up in infancy in comparison to children with other temperament profiles in infancy. Participants were 996 mothers and children in the NICHD SECC studied from 6 months to first grade. Latent growth curve…

  20. Intraoperative bleeding control during cesarean delivery of complete placenta previa with transient occlusion of uterine arteries

    PubMed Central

    Kim, Ju Hyun; Joung, Eun-Ju; Lee, Soo-Jung; Kwack, Jae Young

    2015-01-01

    There are few methods to control heavy intra-operative bleeding during cesarean delivery of placenta previa. Transient occlusion of uterine arteries (TOUA) during operation has previously been reported as a quick and safe method to control intra-operative uterine bleeding. We reported 2 cases of cesarean delivery with complete placenta previa in which TOUA was performed to safely reduce intra-operative complication, especially heavy intra-operative bleeding. In the 2 cases, cesarean deliveries were safe and without any complications under the TOUA method. TOUA can be a good method to control heavy intra-operative bleeding during cesarean delivery of complete placenta previa with risk of heavy bleeding. PMID:26623419

  1. Recent Warming of Lake Kivu

    PubMed Central

    Katsev, Sergei; Aaberg, Arthur A.; Crowe, Sean A.; Hecky, Robert E.

    2014-01-01

    Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient. PMID:25295730

  2. Recent warming of lake Kivu.

    PubMed

    Katsev, Sergei; Aaberg, Arthur A; Crowe, Sean A; Hecky, Robert E

    2014-01-01

    Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient. PMID:25295730

  3. Amplified Arctic warming by phytoplankton under greenhouse warming.

    PubMed

    Park, Jong-Yeon; Kug, Jong-Seong; Bader, Jürgen; Rolph, Rebecca; Kwon, Minho

    2015-05-12

    Phytoplankton have attracted increasing attention in climate science due to their impacts on climate systems. A new generation of climate models can now provide estimates of future climate change, considering the biological feedbacks through the development of the coupled physical-ecosystem model. Here we present the geophysical impact of phytoplankton, which is often overlooked in future climate projections. A suite of future warming experiments using a fully coupled ocean-atmosphere model that interacts with a marine ecosystem model reveals that the future phytoplankton change influenced by greenhouse warming can amplify Arctic surface warming considerably. The warming-induced sea ice melting and the corresponding increase in shortwave radiation penetrating into the ocean both result in a longer phytoplankton growing season in the Arctic. In turn, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating, triggering additional positive feedbacks in the Arctic, and consequently intensifying the Arctic warming further. Our results establish the presence of marine phytoplankton as an important potential driver of the future Arctic climate changes. PMID:25902494

  4. Amplified Arctic warming by phytoplankton under greenhouse warming

    PubMed Central

    Park, Jong-Yeon; Kug, Jong-Seong; Bader, Jürgen; Rolph, Rebecca; Kwon, Minho

    2015-01-01

    Phytoplankton have attracted increasing attention in climate science due to their impacts on climate systems. A new generation of climate models can now provide estimates of future climate change, considering the biological feedbacks through the development of the coupled physical–ecosystem model. Here we present the geophysical impact of phytoplankton, which is often overlooked in future climate projections. A suite of future warming experiments using a fully coupled ocean−atmosphere model that interacts with a marine ecosystem model reveals that the future phytoplankton change influenced by greenhouse warming can amplify Arctic surface warming considerably. The warming-induced sea ice melting and the corresponding increase in shortwave radiation penetrating into the ocean both result in a longer phytoplankton growing season in the Arctic. In turn, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating, triggering additional positive feedbacks in the Arctic, and consequently intensifying the Arctic warming further. Our results establish the presence of marine phytoplankton as an important potential driver of the future Arctic climate changes. PMID:25902494

  5. Terrestrial Carbon Cycle Feedback to Climate Warming: Experimental Evidence

    NASA Astrophysics Data System (ADS)

    Luo, Y.; Zhou, X.; Sherry, R.

    2006-12-01

    Global climate modeling has demonstrated that climate warming would stimulate respiratory CO2 release from the terrestrial ecosystems to the atmosphere, which in turn leads to more warming in the climate system. This positive feedback between the climate change and the terrestrial carbon cycle can form a vicious cycle that potentially leads to a dangerous threat to ecosystem functioning and service. Some of the key processes underlying this feedback loop, however, have not been carefully examined by experimental studies. Those key processes include temperature sensitivity of ecosystem carbon influx; regulation of carbon processes by warming-induced changes in species composition, and nutrient and water availability; and phenology and timing of ecosystem processes under warming. We have conducted two warming experiments in a Southern Great Plains prairie to examine ecosystem responses to climate warming. We used infrared heaters to elevate soil temperature by approximately 2.0 and 4.0 oC, respectively, during the experimental period. Our results indicate that plant biomass growth increased by approximately 20% in the warmed plots in comparison to that in the control plots. The increased plant productivity likely resulted from extended length of growing seasons since warming advanced phenology of early-flowering species and delayed phenology of late-flowering species, leading to an extension of the growing season. Leaf photosynthesis, however, was not strongly affected by warming. Warming also considerably increased C4 plant biomass and caused slight decreases in growth of C3 plants. Increased C4 biomass and litter production resulted in decreases in quality and decomposition of bulk litter at the ecosystem scale, leading to an increase in litter mass at the soil surface. Soil respiration did not significantly increase in the first two years but increased by 8-10% in the last several years, largely due to increased root respiration and litter pool sizes. We did not observe much change in soil C content under warming, indicating that increased plant biomass counterbalanced the increased carbon loss via respiration. The increased biomass production was accompanied by increases in plant nitrogen uptake and use efficiency. Decreased litter quality and increased litter pools may trigger a negative nitrogen feedback to decrease nitrogen releases from litter and availability for plants over time. Overall, our data from the Great Plains prairie do not support the notion that warming stimulation of soil respiration is the major feedback process to climate change. A realistic prediction of the future carbon cycle and climate change may require more ecosystem processes other than the respiration to be incorporated into climate models.

  6. A quantitative microscopic approach to predict local recurrence based on in vivo intraoperative imaging of sarcoma tumor margins.

    PubMed

    Mueller, Jenna L; Fu, Henry L; Mito, Jeffrey K; Whitley, Melodi J; Chitalia, Rhea; Erkanli, Alaattin; Dodd, Leslie; Cardona, Diana M; Geradts, Joseph; Willett, Rebecca M; Kirsch, David G; Ramanujam, Nimmi

    2015-11-15

    The goal of resection of soft tissue sarcomas located in the extremity is to preserve limb function while completely excising the tumor with a margin of normal tissue. With surgery alone, one-third of patients with soft tissue sarcoma of the extremity will have local recurrence due to microscopic residual disease in the tumor bed. Currently, a limited number of intraoperative pathology-based techniques are used to assess margin status; however, few have been widely adopted due to sampling error and time constraints. To aid in intraoperative diagnosis, we developed a quantitative optical microscopy toolbox, which includes acriflavine staining, fluorescence microscopy, and analytic techniques called sparse component analysis and circle transform to yield quantitative diagnosis of tumor margins. A series of variables were quantified from images of resected primary sarcomas and used to optimize a multivariate model. The sensitivity and specificity for differentiating positive from negative ex vivo resected tumor margins was 82 and 75%. The utility of this approach was tested by imaging the in vivo tumor cavities from 34 mice after resection of a sarcoma with local recurrence as a bench mark. When applied prospectively to images from the tumor cavity, the sensitivity and specificity for differentiating local recurrence was 78 and 82%. For comparison, if pathology was used to predict local recurrence in this data set, it would achieve a sensitivity of 29% and a specificity of 71%. These results indicate a robust approach for detecting microscopic residual disease, which is an effective predictor of local recurrence. PMID:25994353

  7. Glaciology: Repeat warming in Greenland

    NASA Astrophysics Data System (ADS)

    Smith, Benjamin E.

    2012-06-01

    Greenland's glaciers have lost significant amounts of ice over the past decade. Rediscovered historical images of the ice margin show a record of southeast Greenland's response to the last major warming event in the 1930s.

  8. Separating Contributions from Anthropogenic Warming and from Natural Oscillations to Global Warming

    NASA Astrophysics Data System (ADS)

    Konrad Stips, Adolf; Macias, Diego; Garcia-Gorriz, Elisa

    2014-05-01

    During the past five decades, global air temperatures have been warming at a rather high rate (IPCC-2013) resulting in scientific and social concern. This warming trend is observed in field data sampling and model simulations and affects both air temperatures over land and over the ocean. However, the warming rate changes with time and this has led to question the causes underlying the observed trends. Here, we analyze recent measured and modeled data on global mean surface air temperature anomalies (GMTA) covering the last 160 years using spectral techniques. The spectral analysis of the measured data does show a strong secular trend (ST) and a clear multidecadal sinusoidal oscillation (MDV) that resembles the Atlantic Multidecadal Oscillation (AMO). The observed acceleration of the warming during the period from 1970 to 2000 therefore appears to be caused by a superimposition of anthropogenic-induced warming (~60%) with the positive phase of a multidecadal oscillation (~40%), while the recent slowdown (hiatus) of this tendency is likely due to a shift in the MDV phase. It has been proposed that this change in the MDV phase could mask the effect of global warming in the forthcoming decades and our analysis indicates that this is quite likely, the current hiatus being already a manifestation of this phenomenon. Most current generation global circulation models (CMIP5) do not reproduce this MDV and are missing the actual temperature hiatus. Therefore, it is less likely that such models could correctly forecast the temperature evolution during the coming decades. We propose here to use the climate dynamics that is inherent in the GMTA data to forecast temperatures until 2100. These forecasts, based on the analyzed secular trend and the multidecadal oscillations are indeed capable of reproducing the actual hiatus and generally result, in comparison to CMIP5 forecasts, in much lower temperature increases for 2100 of only about 1oC. Global mean air temperatures could be even decreasing for the next 2-3 decades. Henceforth, for a correct assessment of the anthropogenic-induced warming of the global air temperatures in the future natural multidecadal temperature oscillations should be taken into account.

  9. Compact intraoperative imaging device for sentinel lymph node mapping

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Bauer, Adam Q.; Akers, Walter; Sudlow, Gail; Liang, Kexian; Shen, Duanwen; Berezin, Mikhail; Culver, Joseph P.; Achilefu, Samuel

    2011-03-01

    We have developed a novel real-time intraoperative fluorescence imaging device that can detect near-infrared (NIR) fluorescence and map sentinel lymph nodes (SLNs). In contrast to conventional imaging systems, this device is compact, portable, and battery-operated. It is also wearable and thus allows hands-free operation of clinicians. The system directly displays the fluorescence in its goggle eyepiece, eliminating the need for a remote monitor. Using this device in murine lymphatic mapping, the SLNs stained with indocyanine green (ICG) can be readily detected. Fluorescence-guided SLN resection under the new device was performed with ease. Ex vivo examination of resected tissues also revealed high fluorescence level in the SLNs. Histology further confirmed the lymphatic nature of the resected SLNs.

  10. Beyond conventional pathology: towards preoperative and intraoperative lymph node staging.

    PubMed

    Winter, Marnie; Gibson, Rachel; Ruszkiewicz, Andrew; Thompson, Sarah K; Thierry, Benjamin

    2015-02-15

    Accurate detection of lymph node metastases is critical for many solid tumours to guide treatment strategies and determine prognostic outcomes. The gold standard for detection of metastasis is by histological analysis of formalin-fixed paraffin-embedded (FFPE) sections of removed lymph nodes; this analysis method has remained largely unchanged for decades. Recent studies have highlighted limitations in the sensitivity of this approach, at least in its current clinical use, to detect very small metastatic deposits. Importantly, the poor prognostic outcomes associated with the presence of such small tumour deposits are now well established in a number of cancers. In addition, histological analysis of FFPE sections cannot be used practically for intraoperative node assessment. Novel lymph node staging technologies are therefore actively being developed. This review critically presents the main advances in this field and discusses why these technologies have not been able to provide a better alternative to the current gold standard diagnostic technique. PMID:24469881

  11. Intraoperative radiation therapy first part: rationale and techniques.

    PubMed

    Calvo, Felipe A; Meirino, Rosa M; Orecchia, Roberto

    2006-08-01

    Intraoperative radiotherapy (IORT) is a technique where a high, single-fraction radiation dose is delivered during a surgical procedure to macroscopic tumours or tumour beds with minimal exposure of surroundings tissues which are displaced and shielded during the procedure. In this paper, the rationale for and use of IORT, both with electron beams (IOERT) and high-dose-rate brachytherapy (HDR-IORT) are discussed. For most tumours, the likelihood of obtaining local control (LC) improves when increasing doses can be administered. In many clinical situations, however, the dose that can be delivered safely to the tumour target is limited by the risk of damaging normal tissues. Special consideration is therefore given on this paper to the relationship between dose, LC and possible complications. Criteria for patient's selection and evaluation and information on sequencing and techniques are presented as well as some considerations on the need for a proper programme on quality assurance and periodical reporting of data. PMID:16844383

  12. Is current clinical practice modified about intraoperative breast irradiation?

    PubMed Central

    Massa, Michela; Franchelli, Simonetta; Panizza, Renzo; Massa, Tiberio

    2016-01-01

    After the results obtained in the two randomized clinical trial, the ELIOT trial and the TARGIT-A trial, a heated debate is going on concerning the question of applying intraoperative radiotherapy (IORT) instead of postoperative whole breast irradiation (WBI) after breast conservative treatment. Currently, many centers are applying the IORT following the strict selection criteria dictated by the working groups American Society for Radiation Oncology (ASTRO) and Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) and monitoring the oncological outcome together with radiation toxicity on breast tissue. The clinical experience of the Geneva University Hospital regarding the use of the Intrabeam system is evaluated and compared with current evidences. PMID:27199511

  13. Is current clinical practice modified about intraoperative breast irradiation?

    PubMed

    Massa, Michela; Franchelli, Simonetta; Panizza, Renzo; Massa, Tiberio

    2016-04-01

    After the results obtained in the two randomized clinical trial, the ELIOT trial and the TARGIT-A trial, a heated debate is going on concerning the question of applying intraoperative radiotherapy (IORT) instead of postoperative whole breast irradiation (WBI) after breast conservative treatment. Currently, many centers are applying the IORT following the strict selection criteria dictated by the working groups American Society for Radiation Oncology (ASTRO) and Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) and monitoring the oncological outcome together with radiation toxicity on breast tissue. The clinical experience of the Geneva University Hospital regarding the use of the Intrabeam system is evaluated and compared with current evidences. PMID:27199511

  14. Quality assurance and performance improvement in intraoperative neurophysiologic monitoring programs.

    PubMed

    Tamkus, Arvydas A; Rice, Kent S; McCaffrey, Michael T

    2013-03-01

    Quality assurance (QA) as it relates to intraoperative neurophysiological monitoring (IONM) can be defined as the systematic monitoring, evaluation, and modification of the IONM service to insure that desired standards of quality are being met. In practice, that definition is usually extended to include the concept that the quality of the IONM service will be improved wherever possible and, although there are some differences in the two terms, in this article the term QA will be understood to include quality improvement (QI) processes as well. The measurement and documentation of quality is becoming increasingly important to healthcare providers. This trend is being driven by pressures from accrediting agencies, payers, and patients. The essential elements of a QA program are described. A real-life example of QA techniques and management relevant to IONM providers is presented and discussed. PMID:23682539

  15. Intraoperative Periprosthetic Femur Fracture: A Biomechanical Analysis of Cerclage Fixation.

    PubMed

    Frisch, Nicholas B; Charters, Michael A; Sikora-Klak, Jakub; Banglmaier, Richard F; Oravec, Daniel J; Silverton, Craig D

    2015-08-01

    Intraoperative periprosthetic femur fracture is a known complication of total hip arthroplasty (THA) and a variety of cerclage systems are available to manage these fractures. The purpose of this study was to examine the in situ biomechanical response of cerclage systems for fixation of periprosthetic femur fractures that occur during cementless THA. We compared cobalt chrome (CoCr) cables, synthetic cables, monofilament wires and hose clamps under axial compressive and torsional loading. Metallic constructs with a positive locking system performed the best, supporting the highest loads with minimal implant subsidence (both axial and angular) after loading. Overall, the CoCr cable and hose clamp had the highest construct stiffness and least reduction in stiffness with increased loading. They were not demonstrably different from each other. PMID:25765131

  16. Intraoperative hypertensive crisis due to a catecholamine-secreting esthesioneuroblastoma

    PubMed Central

    Salmasi, Vafi; Schiavi, Adam; Binder, Zev A.; Ruzevick, Jacob; Orr, Brent A.; Burger, Peter C.; Ball, Douglas W.; Blitz, Ari M.; Koch, Wayne M.; Ishii, Masaru; Gallia, Gary L.

    2015-01-01

    Background Although uncommon, esthesioneuroblastomas may produce clinically significant amounts of catecholamines. Methods We report a patient with a catecholamine-secreting esthesioneuroblastoma who developed intraoperative hypertensive crisis. Results A patient with history of hypertension was referred to our skull base center for management of a residual esthesioneuroblastoma. A staged endonasal endoscopic approach was planned. At the conclusion of the first stage, a hypertensive crisis occurred. Work-up revealed elevated levels of serum and urinary catecholamines. The patient was treated with alpha adrenoceptor blockade prior to the second stage. Serum catecholamine levels following this second stage were normal. On immunohistochemical analysis, the tumor cells were found to be positive for tyrosine hydroxylase, the rate limiting enzyme in cathecholamine synthesis, and achaete-scute homologue 1, a transcription factor essential in the development of olfactory and sympathetic neurons. Conclusion Catecholamine production should be considered in the differential of unexpected extreme hypertension during surgical resection of esthesioneuroblastoma. PMID:25352487

  17. Cytology of bone lesions by intraoperative sampling during fracture treatment.

    PubMed

    Kinias, Ioannis S; Rammou-Kinia, Rea

    2002-03-01

    Cytology was performed on 314 patients who were treated by surgery for hip joint fracture, to determine and evaluate the role, accuracy, and perspective of intraoperative bone sampling. Specimens were collected from bone lesions during surgery by imprints or driller washing in normal saline. The results were compared with those of subsequent biopsies or clinical follow-up. All 13 neoplastic cases (malignant or benign) were identified by cytology. An accuracy rate of 69.2% was achieved by this method when the type and origin of the neoplasms were to be conclusive. There were no false-positive diagnoses, and all benign conditions showed negative results on cytology (specificity and sensitivity of 100%). Cytology can play a valuable role in the diagnosis of bone lesions. The morphologic diagnostic criteria allow for a high level of diagnostic accuracy of cytologic assessments in most cases of bone lesions, no matter the sampling technique. PMID:11892017

  18. Intraoperative raster photogrammetry--the PAR Corneal Topography System.

    PubMed

    Belin, M W

    1993-01-01

    The PAR Corneal Topography System (CTS) is a computer-driven corneal imaging system that uses close-range raster photogrammetry to measure and produce a topographic map of the corneal surface. The CTS determines distortion in a projected two-dimensional grid. Unlike Placido-disc-based videokeratoscopes, the PAR CTS produces a true topographic map (elevation map) and requires neither a smooth reflective surface nor precise spatial alignment for accurate imaging. Because the system uses two noncoaxial optical paths, it can be integrated into other optical devices. A modified CTS was integrated into an experimental erbium: YAG photoablative laser. The CTS successfully imaged corneas before, after, and during laser photoablation. Its ability to image nonreflective surfaces and to be integrated into other optical systems may make it suitable for intraoperative refractive monitoring. PMID:8450443

  19. Bacteremia during dacryocystorhinostomy: results of intra-operative blood cultures

    PubMed Central

    2014-01-01

    Background The aims of the study are to assess the prevalence of bacteremia during dacryocystorhinostomy (DCR) and to assess whether there is a need for post-operative prophylaxis. Prospective interventional study of 52 consecutive dacryocystorhinostomy performed in 50 patients over a period of 1 year from 2013 to 2014. Blood was drawn under strict aseptic conditions during two separate time points: fashioning of the nasal mucosal and creation of lacrimal sac flaps. The blood was inoculated into two blood culture bottles: the dual media as well as Columbia broth. Following withdrawal of blood, all patients received an intraoperative single dose of a cephalosporin antibiotic. Clean cases of primary acquired nasolacrimal duct obstructions (PANDO) without any sac discharge upon marsupialization (22%, 11/50) were not prescribed routine post-operative prophylaxis, whereas the remaining were prescribed oral antibiotics for 5 days. Results The mean age of patients was 41 years (range, 4–61 years). The most common diagnosis (70%, 35/50) was primary acquired nasolacrimal duct obstruction. Acute dacryocystitis was noted in 12% (6/50). External DCR was performed in 65% (34/52) and endoscopic DCR in 35% (18/52) of the cases. All the blood cultures were uniformly negative both in terms of abnormal physical changes in media as well subcultures; 22% (11/50) did not receive post-operative antibiotic prophylaxis. None of the patients developed any signs of wound infections. The anatomical and functional success rate was achieved in 98%. Conclusions This study did not find any intraoperative bacteremia during dacryocystorhinostomy and that none had wound infection irrespective of post-operative prophylaxis. PMID:25320650

  20. Does intraoperative fluoroscopy improve component positioning in total hip arthroplasty?

    PubMed

    Tischler, Eric H; Orozco, Fabio; Aggarwal, Vinay K; Pacheco, Haroldo; Post, Zachary; Ong, Alvin

    2015-01-01

    Accurate placement of components is imperative for successful outcomes after total hip arthroplasty (THA). Although technology-assisted techniques offer the potential for greater accuracy in prosthesis positioning, the need for additional resources prevents their widespread use. The goal of this study was to compare primary THA procedures performed with and without intraoperative fluoroscopic guidance with regard to accuracy of prosthesis placement, operative time, and postoperative complications. The authors reviewed 341 consecutive cases (330 patients) undergoing primary THA at the authors' institution from September 2007 to January 2010. Postoperative anteroposterior radiographs were used to measure acetabular inclination angle, leg length discrepancy, and femoral offset discrepancy. Operative time and postoperative complications related to implant positioning were recorded. Mean acetabular inclination angle, leg length discrepancy, and offset discrepancy for control vs study groups were 43.0° (range, 32.2°-61.4°) vs 43.8° (range, 29.0°-55.1°), 4.75 mm (range, 0-25) vs 4.24 mm (range, 0-27), and 8.47 mm (range, 0-9.7) vs 7.70 mm (range, 0-31), respectively. Complication rates were not significantly different between the control (8.1%) and study (5.3%) groups. Mean operative time was significantly higher in the study group compared with the control group (59.8 vs 52.8 minutes) (P<.0001). The findings showed that intraoperative fluoroscopy may not improve prosthesis accuracy or decrease postoperative complication rates compared with a freehand technique. Because of significantly increased operative time and cost associated with fluoroscopic guidance, the authors discourage the use of this technique in uncomplicated primary THA performed at high-volume arthroplasty institutions. PMID:25611413

  1. Factors associated with intraoperative conversion during robotic sacrocolpopexy

    PubMed Central

    Linder, Brian J.; Chow, George K.; Hertzig, Lindsay L.; Clifton, Marisa; Elliott, Daniel S.

    2015-01-01

    Objective To evaluate for potential predictors of intraoperative conversion from robotic sacrocolpopexy (RSC) to open abdominal sacrocolpopexy. Patients and Methods We identified 83 consecutive patients from 2002-2012 with symptomatic high-grade post-hysterectomy vaginal vault prolapse that underwent RSC. Multiple clinical variables including patient age, comorbidities (body-mass index [BMI], hypertension, diabetes mellitus, tobacco use), prior intra-abdominal surgery and year of surgery were evaluated for potential association with conversion. Results Overall, 14/83 cases (17%) required conversion to an open sacrocolpopexy. Patients requiring conversion were found to have a significantly higher BMI compared to those who did not (median 30.2kg/m2 versus 25.8kg/m2; p=0.003). Other medical and surgical factors evaluated were similar between the cohorts. When stratified by increasing BMI, conversion remained associated with an increased BMI. That is, conversion occurred in 3.8% (1/26) of patients with BMI ≤25 kg/m2, 14.7% (5/34) with BMI 25-29.9 kg/m2 and 34.7% (8/23) with BMI ≥30 kg/m2 (p=0.004). When evaluated as a continuous variable, BMI was also associated with a significantly increased risk of conversion to an open procedure (OR 1.18, p=0.004). Conclusions Higher BMI was the only clinical factor associated with a significantly increased risk of intra-operative conversion during robotic sacrocolpopexy. Recognition of this may aid in pre-operative counseling and surgical patient selection. PMID:26005974

  2. Hybrid intraoperative pulmonary artery stenting in redo congenital cardiac surgeries

    PubMed Central

    Sridhar, Anuradha; Subramanyan, Raghavan; Premsekar, Rajasekaran; Chidambaram, Shanthi; Agarwal, Ravi; Manohar, Soman Rema Krishna; Cherian, K.M.

    2014-01-01

    Objective Reconstruction of branch pulmonary arteries (PAs) can be challenging in redo congenital heart surgeries. Treatment options like percutaneous stent implantation and surgical patch angioplasty may yield suboptimal results. We present our experience with hybrid intraoperative stenting which may be an effective alternative option. Methods We retrospectively analyzed data of all patients with PA stenosis who underwent intraoperative PA branch stenting in our institution between January 2011 and December 2012. Results Ten patients [6 females, median age 10 (1.4 to 37) years], underwent hybrid stenting of the PA. Primary cardiac diagnoses were pulmonary atresia with ventricular septal defect (VSD) in three patients, pulmonary atresia with intact ventricular septum in two, Tetralogy of Fallot (TOF) in one, Double outlet right ventricle (DORV) with pulmonary stenosis (PS) in one, complex single ventricle in two and VSD with bilateral branch PA stenosis in one patient. Concomitant surgeries were revision/reconstruction of RV-PA conduit in 4, Fontan completion in 4, repair of TOF with conduit placement in 1 and VSD closure in 1 patient. The left PA was stented in 7, the right in 2 and both in 1, with a total of 11 stents. There were no complications related to stent implantation. Two early postoperative deaths were unrelated to stent implantation. At mean follow-up period of 14.8 (12–26) months, stent position and patency were satisfactory in all survivors. None of them needed repeat dilatation or surgical reintervention. Conclusion Hybrid stenting of branch PA is a safe and effective option for PA reconstruction in redo cardiac surgeries. With meticulous planning, it can be safely performed without fluoroscopy. PMID:24581095

  3. Adjuvant Intraoperative Photodynamic Therapy in Head and Neck Cancer

    PubMed Central

    Rigual, Nestor R.; Shafirstein, Gal; Frustino, Jennifer; Seshadri, Mukund; Cooper, Michele; Wilding, Gregory; Sullivan, Maureen A.; Henderson, Barbara

    2015-01-01

    IMPORTANCE There is an immediate need to develop local intraoperative adjuvant treatment strategies to improve outcomes in patients with cancer who undergo head and neck surgery. OBJECTIVES To determine the safety of photodynamic therapy with 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-a (HPPH) in combination with surgery in patients with head and neck squamous cell carcinoma. DESIGN, SETTING, AND PARTICIPANTS Nonrandomized, single-arm, single-site, phase 1 study at a comprehensive cancer center among 16 adult patients (median age, 65 years) with biopsy-proved primary or recurrent resectable head and neck squamous cell carcinoma. INTERVENTIONS Intravenous injection of HPPH (4.0 mg/m2), followed by activation with 665-nm laser light in the surgical bed immediately after tumor resection. MAIN OUTCOMES AND MEASURES Adverse events and highest laser light dose. RESULTS Fifteen patients received the full course of treatment, and 1 patient received HPPH without intraoperative laser light because of an unrelated myocardial infarction. Disease sites included larynx (7 patients), oral cavity (6 patients), skin (1 patient), ear canal (1 patient), and oropharynx (1 patient, who received HPPH only). The most frequent adverse events related to photodynamic therapy were mild to moderate edema (9 patients) and pain (3 patients). One patient developed a grade 3 fistula after salvage laryngectomy, and another patient developed a grade 3 wound infection and mandibular fracture. Phototoxicity reactions included 1 moderate photophobia and 2 mild to moderate skin burns (2 due to operating room spotlights and 1 due to the pulse oximeter). The highest laser light dose was 75 J/cm2. CONCLUSIONS AND RELEVANCE The adjuvant use of HPPH-photodynamic therapy and surgery for head and neck squamous cell carcinoma seems safe and deserves further study. PMID:23868427

  4. Single-trial detection for intraoperative somatosensory evoked potentials monitoring.

    PubMed

    Hu, L; Zhang, Z G; Liu, H T; Luk, K D K; Hu, Y

    2015-12-01

    Abnormalities of somatosensory evoked potentials (SEPs) provide effective evidence for impairment of the somatosensory system, so that SEPs have been widely used in both clinical diagnosis and intraoperative neurophysiological monitoring. However, due to their low signal-to-noise ratio (SNR), SEPs are generally measured using ensemble averaging across hundreds of trials, thus unavoidably producing a tardiness of SEPs to the potential damages caused by surgical maneuvers and a loss of dynamical information of cortical processing related to somatosensory inputs. Here, we aimed to enhance the SNR of single-trial SEPs using Kalman filtering and time-frequency multiple linear regression (TF-MLR) and measure their single-trial parameters, both in the time domain and in the time-frequency domain. We first showed that, Kalman filtering and TF-MLR can effectively capture the single-trial SEP responses and provide accurate estimates of single-trial SEP parameters in the time domain and time-frequency domain, respectively. Furthermore, we identified significant correlations between the stimulus intensity and a set of indicative single-trial SEP parameters, including the correlation coefficient (between each single-trial SEPs and their average), P37 amplitude, N45 amplitude, P37-N45 amplitude, and phase value (at the zero-crossing points between P37 and N45). Finally, based on each indicative single-trial SEP parameter, we investigated the minimum number of trials required on a single-trial basis to suggest the existence of SEP responses, thus providing important information for fast SEP extraction in intraoperative monitoring. PMID:26557929

  5. Application of intraoperative 3D ultrasound during navigated tumor resection.

    PubMed

    Lindner, D; Trantakis, C; Renner, C; Arnold, S; Schmitgen, A; Schneider, J; Meixensberger, J

    2006-08-01

    Intraoperative 3D ultrasound (3D-iUS) may enhance the quality of neuronavigation by adding information about brain shift and tumor remnants. The aim of our study was to prove the concept of 3D ultrasound on the basis of technical and human effects. A 3D-ultrasound navigation system consisting of a standard personal computer containing a video grabber card in combination with an optical tracking system (NDI Polaris) and a standard ultrasound device (Siemens Omnia) with a 7.5 MHz probe was used. 3D-iUS datasets were acquired after craniotomy, at different subsequent times of the procedure and overlaid with preoperative MRI. All patients underwent early postoperative 3D MRI including contrast agent within 24 hours after surgery. Acquisition of 3D iUS and the fusion with preoperative MRI was successful in 22/23 patients. The expenditure of time was at least 5 minutes for one intraoperative 3D US dataset. The technique was used three to seven times during surgery. The quality of the ultrasound images was superior in cases of metastasis, meningeoma and angioma over those in malignant glioma. Brain shifting ranged from 2-25 mm depending on localization and kind of tumor. A resection control was possible in 78%. All six neurosurgeons demonstrated a learning curve. The introduction of 3D ultrasound has increased the value of neuronavigation substantially, making it possible to update several times during surgery and minimize the problem of brain shift. Configuration of both the 3D iUS based on a standard ultrasound system and the MR navigation system is time- and especially cost-effective. Faster navigational datasets and more intuitive image-guided surgery enable novel and user-friendly display techniques. PMID:17041829

  6. The fate of unrevised stenoses in infrainguinal autologous vein grafts as detected by intraoperative duplex scanning.

    PubMed

    Idu, Mirza M; Ubbink, Dirk; Legemate, Dink A

    2005-01-01

    Intraoperative infrainguinal autologous vein graft stenoses are common, and some authors advise revision of these stenoses. But the natural history of these lesions is not clear. This study was undertaken to determine the natural history of duplex-detected intraoperative stenoses with a nonrevision policy. Intraoperative duplex scanning was performed in 46 infrainguinal autologous vein bypasses. The surgeon was blinded for the results of the intraoperative duplex scan and no intraoperative graft revision or modification of the routine postoperative protocol was performed after the duplex scan. Intraoperative duplex parameters and patient and bypass characteristics were correlated with the occurrence of an early graft event (occlusion or revision of a patent graft within 6 weeks postoperatively), which was the study's primary endpoint. Early graft event rate was 37% (17/46). PSV ratio and PSV-max were the only parameters with a significant correlation with the occurrence of an early graft event. An intraoperatively measured PSV ratio of > or =3.0 was the best predictor of an early graft failure with a sensitivity of 71% (95% CI: 50-83%) and a specificity of 90% (95% CI: 78-97%). In 12 of the 15 (80%) grafts matching this criterion an early graft event occurred, while only 5 (16%) early graft events occurred in the remaining 31 grafts (ie, a negative predictive value of 84%). When a PSV ratio of > or =3.0 was used as a cutoff value to predict early postoperative graft events, the likelihood ratios for a positive and negative test result were respectively 6.82 (95% CI: 2.23-20.8) and 0.33 (95% CI: 0.16-0.69). Unrevised intraoperative duplex-detected stenoses in infrainguinal autologous vein graft stenoses are a serious threat to early graft patency. The presence of an intraoperatively detected graft stenosis with a PSV ratio > or =3.0 is a strong predictor of early graft failure. PMID:16079940

  7. Intraoperative Imaging Guidance for Sentinel Node Biopsy in Melanoma Using a Mobile Gamma Camera

    PubMed Central

    Dengel, Lynn T.; More, Mitali J.; Judy, Patricia G.; Petroni, Gina R.; Smolkin, Mark E.; Rehm, Patrice K.; Majewski, Stan; Williams, Mark B.; Slingluff, Craig L.

    2016-01-01

    Objective To evaluate the sensitivity and clinical utility of intraoperative mobile gamma camera (MGC) imaging in sentinel lymph node biopsy (SLNB) in melanoma. Background The false-negative rate for SLNB for melanoma is approximately 17%, for which failure to identify the sentinel lymph node (SLN) is a major cause. Intraoperative imaging may aid in detection of SLN near the primary site, in ambiguous locations, and after excision of each SLN. The present pilot study reports outcomes with a prototype MGC designed for rapid intraoperative image acquisition. We hypothesized that intraoperative use of the MGC would be feasible and that sensitivity would be at least 90%. Methods From April to September 2008, 20 patients underwent Tc99 sulfur colloid lymphoscintigraphy, and SLNB was performed with use of a conventional fixed gamma camera (FGC), and gamma probe followed by intraoperative MGC imaging. Sensitivity was calculated for each detection method. Intraoperative logistical challenges were scored. Cases in which MGC provided clinical benefit were recorded. Results Sensitivity for detecting SLN basins was 97% for the FGC and 90% for the MGC. A total of 46 SLN were identified: 32 (70%) were identified as distinct hot spots by preoperative FGC imaging, 31 (67%) by preoperative MGC imaging, and 43 (93%) by MGC imaging pre- or intraoperatively. The gamma probe identified 44 (96%) independent of MGC imaging. The MGC provided defined clinical benefit as an addition to standard practice in 5 (25%) of 20 patients. Mean score for MGC logistic feasibility was 2 on a scale of 19 (1 = best). Conclusions Intraoperative MGC imaging provides additional information when standard techniques fail or are ambiguous. Sensitivity is 90% and can be increased. This pilot study has identified ways to improve the usefulness of an MGC for intraoperative imaging, which holds promise for reducing false negatives of SLNB for melanoma. PMID:21475019

  8. Intraoperative Imaging Guidance for Sentinel Node Biopsy in Melanoma Using a Mobile Gamma Camera

    SciTech Connect

    Dengel, Lynn T; Judy, Patricia G; Petroni, Gina R; Smolkin, Mark E; Rehm, Patrice K; Majewski, Stan; Williams, Mark B

    2011-04-01

    The objective is to evaluate the sensitivity and clinical utility of intraoperative mobile gamma camera (MGC) imaging in sentinel lymph node biopsy (SLNB) in melanoma. The false-negative rate for SLNB for melanoma is approximately 17%, for which failure to identify the sentinel lymph node (SLN) is a major cause. Intraoperative imaging may aid in detection of SLN near the primary site, in ambiguous locations, and after excision of each SLN. The present pilot study reports outcomes with a prototype MGC designed for rapid intraoperative image acquisition. We hypothesized that intraoperative use of the MGC would be feasible and that sensitivity would be at least 90%. From April to September 2008, 20 patients underwent Tc99 sulfur colloid lymphoscintigraphy, and SLNB was performed with use of a conventional fixed gamma camera (FGC), and gamma probe followed by intraoperative MGC imaging. Sensitivity was calculated for each detection method. Intraoperative logistical challenges were scored. Cases in which MGC provided clinical benefit were recorded. Sensitivity for detecting SLN basins was 97% for the FGC and 90% for the MGC. A total of 46 SLN were identified: 32 (70%) were identified as distinct hot spots by preoperative FGC imaging, 31 (67%) by preoperative MGC imaging, and 43 (93%) by MGC imaging pre- or intraoperatively. The gamma probe identified 44 (96%) independent of MGC imaging. The MGC provided defined clinical benefit as an addition to standard practice in 5 (25%) of 20 patients. Mean score for MGC logistic feasibility was 2 on a scale of 1-9 (1 = best). Intraoperative MGC imaging provides additional information when standard techniques fail or are ambiguous. Sensitivity is 90% and can be increased. This pilot study has identified ways to improve the usefulness of an MGC for intraoperative imaging, which holds promise for reducing false negatives of SLNB for melanoma.

  9. Impact of Surface Curvature on Dose Delivery in Intraoperative High-Dose-Rate Brachytherapy

    SciTech Connect

    Oh, Moonseong Wang Zhou; Malhotra, Harish K.; Jaggernauth, Wainwright; Podgorsak, Matthew B.

    2009-04-01

    In intraoperative high-dose-rate (IOHDR) brachytherapy, a 2-dimensional (2D) geometry is typically used for treatment planning. The assumption of planar geometry may cause serious errors in dose delivery for target surfaces that are, in reality, curved. A study to evaluate the magnitude of these errors in clinical practice was undertaken. Cylindrical phantoms with 6 radii (range: 1.35-12.5 cm) were used to simulate curved treatment geometries. Treatment plans were developed for various planar geometries and were delivered to the cylindrical phantoms using catheters inserted into Freiburg applicators of varying dimension. Dose distributions were measured using radiographic film. In comparison to the treatment plan (for a planar geometry), the doses delivered to prescription points were higher on the concave side of the geometry, up to 15% for the phantom with the smallest radius. On the convex side of the applicator, delivered doses were up to 10% lower for small treated areas ({<=} 5 catheters) but, interestingly, the dose error was negligible for large treated areas (>5 catheters). Our measurements have shown inaccuracy in dose delivery when the original planar treatment plan is delivered with a curved applicator. Dose delivery errors arising from the use of planar treatment plans with curved applicators may be significant.

  10. The Great Warming Brian Fagan

    NASA Astrophysics Data System (ADS)

    Fagan, B. M.

    2010-12-01

    The Great Warming is a journey back to the world of a thousand years ago, to the Medieval Warm Period. Five centuries of irregular warming from 800 to 1250 had beneficial effects in Europe and the North Atlantic, but brought prolonged droughts to much of the Americas and lands affected by the South Asian monsoon. The book describes these impacts of warming on medieval European societies, as well as the Norse and the Inuit of the far north, then analyzes the impact of harsh, lengthy droughts on hunting societies in western North America and the Ancestral Pueblo farmers of Chaco Canyon, New Mexico. These peoples reacted to drought by relocating entire communities. The Maya civilization was much more vulnerable that small-scale hunter-gatherer societies and subsistence farmers in North America. Maya rulers created huge water storage facilities, but their civilization partially collapsed under the stress of repeated multiyear droughts, while the Chimu lords of coastal Peru adapted with sophisticated irrigation works. The climatic villain was prolonged, cool La Niñalike conditions in the Pacific, which caused droughts from Venezuela to East Asia, and as far west as East Africa. The Great Warming argues that the warm centuries brought savage drought to much of humanity, from China to Peru. It also argues that drought is one of the most dangerous elements in today’s humanly created global warming, often ignored by preoccupied commentators, but with the potential to cause over a billion people to starve. Finally, I use the book to discuss the issues and problems of communicating multidisciplinary science to the general public.

  11. Spinal arteriovenous malformation: use of intraoperative color Doppler ultrasonography guidance for surgical resection. Case report.

    PubMed

    Baskan, Ozdil; Durdag, Emre; Geyik, Serdar; Elmaci, Ilhan

    2014-12-01

    Spinal arteriovenous malformations (AVMs) may be associated with sensory and motor deficits, bowel or bladder dysfunction, radicular pain or deficit, and back pain. Hemorrhage can occur in the parenchyma leading to the acute onset of symptoms. Neurosurgical resection is one of the way of treatment. Several techniques including intraoperative angiography, dye-injection and the micro Doppler method have proven to be useful during the surgical resection of spinal vascular lesions. Herein, we report our experience with intraoperative ultrasonography (IOUS) and color Doppler ultrasonography guidance for visualizing a spinal cord AVM during surgery. IOUS is a time-saving and noninvasive method for intraoperative imaging of spinal AVM. PMID:25463896

  12. How warm days increase belief in global warming

    NASA Astrophysics Data System (ADS)

    Zaval, Lisa; Keenan, Elizabeth A.; Johnson, Eric J.; Weber, Elke U.

    2014-02-01

    Climate change judgements can depend on whether today seems warmer or colder than usual, termed the local warming effect. Although previous research has demonstrated that this effect occurs, studies have yet to explain why or how temperature abnormalities influence global warming attitudes. A better understanding of the underlying psychology of this effect can help explain the public's reaction to climate change and inform approaches used to communicate the phenomenon. Across five studies, we find evidence of attribute substitution, whereby individuals use less relevant but available information (for example, today's temperature) in place of more diagnostic but less accessible information (for example, global climate change patterns) when making judgements. Moreover, we rule out alternative hypotheses involving climate change labelling and lay mental models. Ultimately, we show that present temperature abnormalities are given undue weight and lead to an overestimation of the frequency of similar past events, thereby increasing belief in and concern for global warming.

  13. Active Movement Warm-Up Routines

    ERIC Educational Resources Information Center

    Walter, Teri; Quint, Ashleigh; Fischer, Kim; Kiger, Joy

    2011-01-01

    This article presents warm-ups that are designed to physiologically and psychologically prepare students for vigorous physical activity. An active movement warm-up routine is made up of three parts: (1) active warm-up movement exercises, (2) general preparation, and (3) the energy system. These warm-up routines can be used with all grade levels…

  14. Analysis of data from spacecraft (stratospheric warmings)

    NASA Technical Reports Server (NTRS)

    Anderson, A. D.

    1974-01-01

    Links between the upper atmosphere and the stratosphere were studied to explain stratospheric warmings, and to correlate the warmings with other terrestrial and solar phenomena. Physical mechanisms for warming, or which may act as a trigger are discussed along with solar and geophysical indices. Two stratospheric warming cases are analyzed.

  15. Non-rigid alignment of preoperative MRI, fMRI, and DT-MRI with intra-operative MRI for enhanced visualization and navigation in image-guided neurosurgery

    PubMed Central

    Archip, Neculai; Clatz, Olivier; Whalen, Stephen; Kacher, Dan; Fedorov, Andriy; Kot, Andriy; Chrisochoides, Nikos; Jolesz, Ferenc; Golby, Alexandra; Black, Peter M.; Warfield, Simon K.

    2012-01-01

    Objective The usefulness of neurosurgical navigation with current visualizations is seriously compromised by brain shift, which inevitably occurs during the course of the operation, significantly degrading the precise alignment between the preoperative MR data and the intra-operative shape of the brain. Our objectives were (i) to evaluate the feasibility of non-rigid registration that compensates for the brain deformations within the time constraints imposed by neurosurgery, and (ii) create augmented reality visualizations of critical structural and functional brain regions during neurosurgery using pre-operatively acquired fMRI and DT-MRI. Materials and Methods Eleven consecutive patients with supratentorial gliomas were included in our study. All underwent surgery at our intra-operative MR imaging–guided therapy facility and have tumors in eloquent brain areas (e.g. precentral gyrus and cortico-spinal tract). Functional MRI and DT-MRI, together with MPRAGE and T2w structural MRI were acquired at 3T prior to surgery. SPGR and T2w images were acquired with a 0.5T magnet during each procedure. Quantitative assessment of the alignment accuracy was carried out and compared with current state-of the-art systems based only on rigid-registration. Results Alignment between preoperative and intra-operative datasets was successfully carried out during surgery for all patients. Overall, the mean residual displacement remaining after non-rigid registration was 1.82 mm. There is a statistically significant improvement in alignment accuracy utilizing our non-rigid registration in comparison to the currently used technology (p<0.001). Conclusions We were able to achieve intra-operative rigid and non-rigid registration of (1) pre-operative structural MRI with intra-operative T1w MRI; (2) pre-operative FMRI with intra-operative T1w MRI, and (3) pre-operative DT-MRI with intra-operative T1w MRI. The registration algorithms as implemented were sufficiently robust and rapid to meet the hard real-time constraints of intra-operative surgical decision making. The validation experiments demonstrate that we can accurately compensate for the deformation of the brain and thus can construct an augmented reality visualization to aid the surgeon. PMID:17289403

  16. Activation of Sahelian monsoon under future warming

    NASA Astrophysics Data System (ADS)

    Schewe, Jacob; Levermann, Anders

    2015-04-01

    Rainfall variability in the Sahel has been affecting the lives of millions through devastating droughts, such as in the 1970s and 80s, but also destructive rain and flood events. Future climate change is likely to alter rainfall patterns, but model projections for the central Sahel diverge significantly, with climate models simulating anything between a slight drying and a substantial wetting trend. Here we analyze 30 coupled global climate model simulations from the CMIP5 archive. We identify seven models where central Sahel rainfall increases by 40% to 300% over the 21st century, under the RCP8.5 concentration pathway. The same models also outperform the rest of the ensemble in reproducing the magnitude of the 1970s/80s drought. The magnitude and seasonality of the projected future rainfall change, together with a concurrent increase in near-surface wind speed, indicate a northward expansion of the West African monsoon domain. We further find that Sahel rainfall does not increase linearly with rising global temperatures; it is insensitive to moderate warming but then abruptly intensifies beyond a certain temperature. This non-linearity is even more pronounced when instead of global warming, sea surface temperature change in the tropical Atlantic moisture source region is considered. We propose an explanation for this behavior based on a self-amplifying dynamic-thermodynamical feedback, and suggest that the gradual increase in oceanic moisture availability under climate change can trigger the sudden activation of a continental monsoon in the Sahel region, which reaches further inland than the present-day, predominantly coastal West African monsoon. Such an abrupt regime change in response to gradual forcing would be consistent with paleoclimatic records from the Sahel region. More detailed comparison between the model simulations that exhibit this sudden rainfall increase under future warming and those that do not may help to verify this hypothesis.

  17. Ion-ion dynamic structure factor of warm dense mixtures

    SciTech Connect

    Gill, N. M.; Heinonen, R. A.; Starrett, C. E.; Saumon, D.

    2015-06-25

    In this study, the ion-ion dynamic structure factor of warm dense matter is determined using the recently developed pseudoatom molecular dynamics method [Starrett et al., Phys. Rev. E 91, 013104 (2015)]. The method uses density functional theory to determine ion-ion pair interaction potentials that have no free parameters. These potentials are used in classical molecular dynamics simulations. This constitutes a computationally efficient and realistic model of dense plasmas. Comparison with recently published simulations of the ion-ion dynamic structure factor and sound speed of warm dense aluminum finds good to reasonable agreement. Using this method, we make predictions of the ion-ion dynamical structure factor and sound speed of a warm dense mixture—equimolar carbon-hydrogen. This material is commonly used as an ablator in inertial confinement fusion capsules, and our results are amenable to direct experimental measurement.

  18. Ion-ion dynamic structure factor of warm dense mixtures

    DOE PAGESBeta

    Gill, N. M.; Heinonen, R. A.; Starrett, C. E.; Saumon, D.

    2015-06-25

    In this study, the ion-ion dynamic structure factor of warm dense matter is determined using the recently developed pseudoatom molecular dynamics method [Starrett et al., Phys. Rev. E 91, 013104 (2015)]. The method uses density functional theory to determine ion-ion pair interaction potentials that have no free parameters. These potentials are used in classical molecular dynamics simulations. This constitutes a computationally efficient and realistic model of dense plasmas. Comparison with recently published simulations of the ion-ion dynamic structure factor and sound speed of warm dense aluminum finds good to reasonable agreement. Using this method, we make predictions of the ion-ionmore » dynamical structure factor and sound speed of a warm dense mixture—equimolar carbon-hydrogen. This material is commonly used as an ablator in inertial confinement fusion capsules, and our results are amenable to direct experimental measurement.« less

  19. Global warming and infectious disease.

    PubMed

    Khasnis, Atul A; Nettleman, Mary D

    2005-01-01

    Global warming has serious implications for all aspects of human life, including infectious diseases. The effect of global warming depends on the complex interaction between the human host population and the causative infectious agent. From the human standpoint, changes in the environment may trigger human migration, causing disease patterns to shift. Crop failures and famine may reduce host resistance to infections. Disease transmission may be enhanced through the scarcity and contamination of potable water sources. Importantly, significant economic and political stresses may damage the existing public health infrastructure, leaving mankind poorly prepared for unexpected epidemics. Global warming will certainly affect the abundance and distribution of disease vectors. Altitudes that are currently too cool to sustain vectors will become more conducive to them. Some vector populations may expand into new geographic areas, whereas others may disappear. Malaria, dengue, plague, and viruses causing encephalitic syndromes are among the many vector-borne diseases likely to be affected. Some models suggest that vector-borne diseases will become more common as the earth warms, although caution is needed in interpreting these predictions. Clearly, global warming will cause changes in the epidemiology of infectious diseases. The ability of mankind to react or adapt is dependent upon the magnitude and speed of the change. The outcome will also depend on our ability to recognize epidemics early, to contain them effectively, to provide appropriate treatment, and to commit resources to prevention and research. PMID:16216650

  20. Warming early Earth and Mars

    SciTech Connect

    Kasting, J.F.

    1997-05-23

    Sagan and Chyba, in their article on page 1217 of this issue, have revived an old debate about how liquid water was maintained on early Earth and Mars despite a solar luminosity 25 to 30% lower than that at present. A theory that has been popular for some time is that greatly elevated concentrations of atmospheric COD produced by the action of the carbonate-silicate cycle, provided enough of a greenhouse effect to warm early Earth. However, Rye et al. have placed geochemical constraints on early atmospheric CO{sub 2} abundances that fall well below the levels needed to warm the surface. These constraints are based on the absence of siderite (FeCO{sub 3}) in ancient soil profiles-a negative and, hence, rather weak form of evidence- and apply to the time period 2.2 to 2.8 billion years ago, when Earth was already middle aged. Nonetheless, the soil data provide some indication that atmospheric CO{sub 2} levels may have been lower than previously thought. An even more serious problem arises if one tries to keep early Mars warm with CO{sub 2}. Model calculations predict that CO{sub 2} clouds would form on Mars in the upper troposphere, reducing the lapse rate and severely limiting the amount of surface warming. A suggestion that CO{sub 2} clouds may have warmed the planet radiatively has yet to be borne out by detailed calculations. 26 refs.

  1. Cosmic Rays and Global Warming

    SciTech Connect

    Sloan, T.; Wolfendale, A. W.

    2008-01-24

    Some workers have claimed that the observed temporal correlations of (low level) terrestrial cloud cover with the cosmic ray intensity changes, due to solar modulation, are causal. The possibility arises, therefore, of a connection between cosmic rays and Global Warming. If true, the implications would be very great. We have examined this claim in some detail. So far, we have not found any evidence in support and so our conclusions are to doubt it. From the absence of corroborative evidence we estimate that less than 15% at the 95% confidence level, of the 11-year cycle warming variations are due to cosmic rays and less than 2% of the warming over the last 43 years is due to this cause. The origin of the correlation itself is probably the cycle of solar irradiance although there is, as yet, no certainty.

  2. Alternative cost-effective method to record 3D intra-operative images: a technical note.

    PubMed

    Barone, Damiano Giuseppe; Ban, Vin Shen; Kirollos, Ramez W; Trivedi, Rikin A; Bulters, Diederik O; Ribas, Guilherme Carvalhal; Santarius, Thomas

    2014-12-01

    The educational value of stereoscopic imaging in neurosurgical training has increasingly been appreciated and its use increased during the last decade. We describe a technique that we developed to acquire and reproduce intra-operative stereoscopic images. PMID:24971491

  3. Use of BIS VISTA bilateral monitor for diagnosis of intraoperative seizures, a case report.

    PubMed

    Iturri Clavero, F; Tamayo Medel, G; de Orte Sancho, K; González Uriarte, A; Iglesias Martínez, A; Martínez Ruíz, A

    2015-12-01

    Changes in BIS (bispectral index) VISTA bilateral monitoring system associated with intraoperative episodes of generalized and focal seizures, during total intravenous anesthesia for resection of a left frontal parasagittal meningioma, are herein described. PMID:25944463

  4. The Dutch Linguistic Intraoperative Protocol: a valid linguistic approach to awake brain surgery.

    PubMed

    De Witte, E; Satoer, D; Robert, E; Colle, H; Verheyen, S; Visch-Brink, E; Mariën, P

    2015-01-01

    Intraoperative direct electrical stimulation (DES) is increasingly used in patients operated on for tumours in eloquent areas. Although a positive impact of DES on postoperative linguistic outcome is generally advocated, information about the neurolinguistic methods applied in awake surgery is scarce. We developed for the first time a standardised Dutch linguistic test battery (measuring phonology, semantics, syntax) to reliably identify the critical language zones in detail. A normative study was carried out in a control group of 250 native Dutch-speaking healthy adults. In addition, the clinical application of the Dutch Linguistic Intraoperative Protocol (DuLIP) was demonstrated by means of anatomo-functional models and five case studies. A set of DuLIP tests was selected for each patient depending on the tumour location and degree of linguistic impairment. DuLIP is a valid test battery for pre-, intraoperative and postoperative language testing and facilitates intraoperative mapping of eloquent language regions that are variably located. PMID:25526520

  5. Single high dose intraoperative electrons for advanced stage pancreatic cancer: Phase I pilot study

    SciTech Connect

    Goldson, A.L.; Ashaveri, E.; Espinoza, M.C.

    1981-07-01

    Phase I toxicity studies with intraoperative radiotherapy proved to be a feasible adjunct to surgery for unresectable malignancies of the pancreas at Howard University Hospital. There have been minimal side effects or complications related to the combination of limited surgical decompression and intraoperative radiotherapy alone. The toxic effects of intraoperative radiotherapy on normal tissues is being assessed on a dose volume basis. Doses of 2000 to 2500 rad in a single exposure to include the pancreas, regional nodes and duodenum are acceptable if the total treatment volume is less than or equal to 100 cm. The tumoricidal effects on the cancer are demonstratable when one reviews the pathological specimens that illustrate massive tumor necrosis and fibros replacement, but in all cases reviewed, viable cancer was noted. Intraoperative radiotherapy, therefore, represents a significant boost dose for resectable, partially resectable or non-resectable tumors when added to conventional external beam irradiation and/or chemotherapy. Preliminary clinical data and minimal toxicity justifies further investigation.

  6. Relationship of Intraoperative Transit Time Flowmetry Findings to Angiographic Graft Patency at Follow-Up.

    PubMed

    Amin, Sanaz; Pinho-Gomes, Ana-Catarina; Taggart, David P

    2016-05-01

    Early and late graft occlusion remains a significant complication of coronary artery bypass grafting. Transit time flowmetry is the most commonly used imaging technique to assess graft patency intraoperatively. Although the value of transit time flowmetry for intraoperative quality control of coronary anastomosis is well established, its standard variables for predicting eventual graft failure remain controversial. This review readdresses the issue of intraoperative transit time flowmetry, with a particular emphasis on defining cutoff values for standard variables and correlating them with the ability to predict midterm and long-term graft patency for arterial and venous conduits. Further research is warranted to support clinically useful recommendations on the intraoperative application and interpretation of transit time flowmetry. PMID:26876343

  7. Evaluating the Dominant Components of Warming in Pliocene Climate Simulations

    NASA Technical Reports Server (NTRS)

    Hill, D. J.; Haywood, A. M.; Lunt, D. J.; Hunter, S. J.; Bragg, F. J.; Contoux, C.; Stepanek, C.; Sohl, L.; Rosenbloom, N. A.; Chan, W.-L.; Kamae, Y.; Zhang, Z.; Abe-Ouchi, A.; Chandler, M. A.; Jost, A.; Lohmann, G.; Otto-Bliesner, B. L.; Ramstein, G.; Ueda, H.

    2014-01-01

    The Pliocene Model Intercomparison Project (PlioMIP) is the first coordinated climate model comparison for a warmer palaeoclimate with atmospheric CO2 significantly higher than pre-industrial concentrations. The simulations of the mid-Pliocene warm period show global warming of between 1.8 and 3.6 C above pre-industrial surface air temperatures, with significant polar amplification. Here we perform energy balance calculations on all eight of the coupled ocean-atmosphere simulations within PlioMIP Experiment 2 to evaluate the causes of the increased temperatures and differences between the models. In the tropics simulated warming is dominated by greenhouse gas increases, with the cloud component of planetary albedo enhancing the warming in most of the models, but by widely varying amounts. The responses to mid-Pliocene climate forcing in the Northern Hemisphere midlatitudes are substantially different between the climate models, with the only consistent response being a warming due to increased greenhouse gases. In the high latitudes all the energy balance components become important, but the dominant warming influence comes from the clear sky albedo, only partially offset by the increases in the cooling impact of cloud albedo. This demonstrates the importance of specified ice sheet and high latitude vegetation boundary conditions and simulated sea ice and snow albedo feedbacks. The largest components in the overall uncertainty are associated with clouds in the tropics and polar clear sky albedo, particularly in sea ice regions. These simulations show that albedo feedbacks, particularly those of sea ice and ice sheets, provide the most significant enhancements to high latitude warming in the Pliocene.

  8. Electronic structure of warm dense silicon dioxide

    NASA Astrophysics Data System (ADS)

    Engelhorn, K.; Recoules, V.; Cho, B. I.; Barbrel, B.; Mazevet, S.; Krol, D. M.; Falcone, R. W.; Heimann, P. A.

    2015-06-01

    The electronic structure of warm dense silicon dioxide has been investigated by x-ray absorption near-edge spectroscopy. An ultrafast optical laser pulse was used to isochorically heat a thin silicon dioxide sample, and measured spectra were compared with simulations generated by molecular dynamics and density functional theory. In comparison with the room temperature spectrum, two features were observed: a peak below the band gap and absorption within the band gap. This behavior was also observed in the simulations. From consideration of the calculated spectra, the peak below the gap is attributed to valence electrons that have been promoted to the conduction band, while absorption within the gap is attributed to broken Si-O bonds.

  9. The Spitzer Warm Mission: Hot Science with a "Warm" Telescope

    NASA Astrophysics Data System (ADS)

    Squires, Gordon K.; Helou, G.; Soifer, T.; Carey, S.; Rebull, L.; Stauffer, J. R.; Storrie-Lombardi, L. J.; Warm Mission white papers, Spitzer

    2007-10-01

    The Spitzer Space Telescope is the infrared component of NASA's family of Great Observatories comprised of the Chandra X-ray Observatory, the Compton Gamma Ray Observatory, and the Hubble Space Telescope. Cryogenically cooled and in Earth-trailing orbit, Spitzer currently offers imaging capabilities from 3.6-160 microns, and spectroscopy from 5-38 microns. In approximately March 2009, the liquid helium cryogen on-board Spitzer will be expended, but the observatory will remain operative with 3.6 and 4.5 micron imaging capabilities over two 5'x5’ fields-of-view. Sensitivity in these channels will remain unchanged from the cryogenic mission. In this "warm” mission phase, Spitzer can operate until early 2014 with high-efficiency, providing up to 35,000 hours of science observing time. This enables several unprecedented opportunities to address fundamental and key scientific questions requiring large allocations of observing time, while maintaining opportunities for broad community use with more "traditional” time allocations. This poster summarizes some of the possible large scientific programs enabled by a Spitzer warm mission, including support for theory and archival programs. The content is summarized from contributed white papers to the Spitzer Warm Mission workshop, held in Pasadena, CA in June 2007. For detailed information on these and other science programs possible with warm Spitzer observations, please see: http://ssc.spitzer.caltech.edu/mtgs/warm/

  10. Safe use of subdermal needles for intraoperative monitoring with MRI.

    PubMed

    Darcey, Terrance M; Kobylarz, Erik J; Pearl, Michael A; Krauss, Patricia J; Ferri, Stephanie A; Roberts, David W; Bauer, David F

    2016-03-01

    OBJECTIVE The purpose of this study was to develop safe, site-specific procedures for placing and leaving subdermal needle leads for intraoperative monitoring (IOM) during intraoperative MRI procedures. METHODS The authors tested a variety of standard subdermal needle electrodes designed and FDA-approved for IOM in the conventional operating room. Testing was used to determine the conditions necessary to avoid thermal injury and significant image artifacts with minimal disruption of IOM and MRI procedures. Phantom testing was performed with a fiber optic (lead) temperature monitoring system and was followed by testing of leads placed in a healthy volunteer. The volunteer testing used electrode placements typical of standard IOM cases, together with radiofrequency (RF) coil placement and imaging sequences routinely employed for these case types. Lead length was investigated to assess heating effects for electrodes placed within the RF coil. RESULTS The authors found that conventional stainless steel (SS) and platinum/iridium (Pt/Ir) subdermal needles can be used safely without significant heating when placed outside the RF coil, and this accounts for the majority or entirety of electrode placements. When placed within the RF coil, Pt/Ir leads produced minimal image artifacts, while SS leads produced potentially significant artifacts. In phantom testing, significant heating was demonstrated in both SS and Pt/Ir leads placed within the RF coil, but only during high-resolution T2-weighted scanning. This problem was largely, but not completely, eliminated when leads were shortened to 25 cm. Human testing was unremarkable except for nonpainful heating detected in a few electrodes during thin-slice (1.5 mm) FLAIR scanning. Transient irritation (skin reddening along the needle tract) was noted at 2 of the electrodes with detectable heating. CONCLUSIONS The authors were satisfied with the safety of their site-specific procedures and have begun with off-label use (following institutional review board approval and obtaining patient informed consent) of tested monitoring leads in cases that combine IOM and MRI. The authors recommend that all facilities perform their own site-specific testing of monitoring leads before proceeding with their routine use. PMID:26926059

  11. Global warming at the summit

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    During the recent summit meeting between Russian President Vladimir Putin and U.S. President Bill Clinton, the two leaders reaffirmed their concerns about global warming and the need to continue to take actions to try to reduce the threat.In a June 4 joint statement, they stressed the need to develop flexibility mechanisms, including international emissions trading, under the Kyoto Protocol to the United Nations Framework Convention on Climate Change. They also noted that initiatives to reduce the risk of greenhouse warming, including specific mechanisms of the Kyoto Protocol, could potentially promote economic growth.

  12. Intraoperative recordings of monophasic action potentials with chronically implantable pacemaker leads.

    PubMed

    Zrenner, B; Müssig, D; Schreieck, J; Weyerbrock, S; Schneider, M; Schaldach, M; Schömig, A; Schmitt, C

    1998-01-01

    Since the development of fractally coated Iridium electrodes recordings of monophasic action potentials are possible. Intraoperative recordings of MAP from 15 pacemaker implantations were done after positioning the chronically implantable pacemaker leads (Biotronik, Berlin, Germany) in the right ventricle by using five screw-in electrodes and ten anchor electrodes. Intraoperative recordings of MAP are possible with all implanted pacemaker leads. The recordings of typical MAP signals were always accompanied with stable electrode positions and good sensing and pacing characteristics. PMID:9474679

  13. Continuous intraoperative TEE monitoring for a child with Fontan pathway undergoing post spinal fusion.

    PubMed

    Farid, Ibrahim S; Reddy, Abelash; Lewis, Judith; Kendrick, Elizabeth J

    2013-02-01

    The following case report describes a very challenging surgical case where the use of intraoperative, continuous TEE monitoring in the prone position was crucial for the anesthetic management (diagnosis and treatment) of a patient with single ventricle physiology. The use of TEE monitoring enabled the anesthesia team to continuously assess hemodynamic stability and respond immediately to hypotension and bradycardia in our patient, thereby providing optimal anesthetic care of the intraoperative spinal fusion patient with Fontan physiology. PMID:23833861

  14. Risk factors for intraoperative calcar fracture in cementless total hip arthroplasty

    PubMed Central

    Miettinen, Simo S A; Mäkinen, Tatu J; Kostensalo, Inari; Mäkelä, Keijo; Huhtala, Heini; Kettunen, Jukka S; Remes, Ville

    2016-01-01

    Background and purpose — Intraoperative periprosthetic femoral fracture is a known complication of cementless total hip arthroplasty (THA). We determined the incidence of—and risk factors for—intraoperative calcar fracture, and assessed its influence on the risk of revision. Patients and methods — This retrospective analysis included 3,207 cementless THAs (in 2,913 patients). 118 intraoperative calcar fractures were observed in these hips (3.7%). A control group of 118 patients/hips without calcar fractures was randomly selected. The mean follow-up was 4.2 (1.8–8.0) years. Demographic data, surgical data, type of implant, and proximal femur morphology were evaluated to determine risk factors for intraoperative calcar fracture. Results — The revision rates in the calcar fracture group and the control group were 10% (95% CI: 5.9–17) and 3.4% (CI: 1.3–8.4), respectively. The revision rate directly related to intraoperative calcar fracture was 7.6%. The Hardinge approach and lower age were risk factors for calcar fracture. In the fracture group, 55 of 118 patients (47%) had at least one risk factor, while only 23 of118 patients in the control group (20%) had a risk factor (p = 0.001). Radiological analysis showed that in the calcar fracture group, there were more deviated femoral anatomies and proximal femur bone cortices were thinner. Interpretation — Intraoperative calcar fracture increased the risk of revision. The Hardinge approach and lower age were risk factors for intraoperative calcar fracture. To avoid intraoperative fractures, special attention should be paid when cementless stems are used with deviant-shaped proximal femurs and with thin cortices. PMID:26541230

  15. Risk factors for intraoperative calcar fracture in cementless total hip arthroplasty.

    PubMed

    Miettinen, Simo S A; Mäkinen, Tatu J; Kostensalo, Inari; Mäkelä, Keijo; Huhtala, Heini; Kettunen, Jukka S; Remes, Ville

    2016-04-01

    Background and purpose - Intraoperative periprosthetic femoral fracture is a known complication of cementless total hip arthroplasty (THA). We determined the incidence of-and risk factors for-intraoperative calcar fracture, and assessed its influence on the risk of revision. Patients and methods - This retrospective analysis included 3,207 cementless THAs (in 2,913 patients). 118 intraoperative calcar fractures were observed in these hips (3.7%). A control group of 118 patients/hips without calcar fractures was randomly selected. The mean follow-up was 4.2 (1.8-8.0) years. Demographic data, surgical data, type of implant, and proximal femur morphology were evaluated to determine risk factors for intraoperative calcar fracture. Results - The revision rates in the calcar fracture group and the control group were 10% (95% CI: 5.9-17) and 3.4% (CI: 1.3-8.4), respectively. The revision rate directly related to intraoperative calcar fracture was 7.6%. The Hardinge approach and lower age were risk factors for calcar fracture. In the fracture group, 55 of 118 patients (47%) had at least one risk factor, while only 23 of118 patients in the control group (20%) had a risk factor (p = 0.001). Radiological analysis showed that in the calcar fracture group, there were more deviated femoral anatomies and proximal femur bone cortices were thinner. Interpretation - Intraoperative calcar fracture increased the risk of revision. The Hardinge approach and lower age were risk factors for intraoperative calcar fracture. To avoid intraoperative fractures, special attention should be paid when cementless stems are used with deviant-shaped proximal femurs and with thin cortices. PMID:26541230

  16. Threshold dose for peripheral neuropathy following intraoperative radiotherapy (IORT) in a large animal model

    SciTech Connect

    Kinsella, T.J.; DeLuca, A.M.; Barnes, M.; Anderson, W.; Terrill, R.; Sindelar, W.F. )

    1991-04-01

    Radiation injury to peripheral nerve is a dose-limiting toxicity in the clinical application of intraoperative radiotherapy, particularly for pelvic and retroperitoneal tumors. Intraoperative radiotherapy-related peripheral neuropathy in humans receiving doses of 20-25 Gy is manifested as a mixed motor-sensory deficit beginning 6-9 months following treatment. In a previous experimental study of intraoperative radiotherapy-related neuropathy of the lumbro-sacral plexus, an approximate inverse linear relationship was reported between the intraoperative dose (20-75 Gy range) and the time to onset of hind limb paresis (1-12 mos following intraoperative radiotherapy). The principal histological lesion in irradiated nerve was loss of large nerve fibers and perineural fibrosis without significant vascular injury. Similar histological changes in irradiated nerves were found in humans. To assess peripheral nerve injury to lower doses of intraoperative radiotherapy in this same large animal model, groups of four adult American Foxhounds received doses of 10, 15, or 20 Gy to the right lumbro-sacral plexus and sciatic nerve using 9 MeV electrons. The left lumbro-sacral plexus and sciatic nerve were excluded from the intraoperative field to allow each animal to serve as its own control. Following treatment, a complete neurological exam, electromyogram, and nerve conduction studies were performed monthly for 1 year. Monthly neurological exams were performed in years 2 and 3 whereas electromyogram and nerve conduction studies were performed every 3 months during this follow-up period. With follow-up of greater than or equal to 42 months, no dog receiving 10 or 15 Gy IORT shows any clinical or laboratory evidence of peripheral nerve injury. However, all four dogs receiving 20 Gy developed right hind limb paresis at 8, 9, 9, and 12 mos following intraoperative radiotherapy.

  17. The Utility of Intraoperative Handheld Gamma Camera for Detection of Sentinel Lymph Nodes in Melanoma.

    PubMed

    Ozkan, Elgin; Eroglu, Aydan

    2015-12-01

    Accurate identification of the sentinel lymph node (SLN) is an important prognostic factor for melanoma. In a minority of cases drainage to interval nodal basins, such as the epitrochlear region, are possible. Intraoperative handheld gamma cameras have been used to detect SLNs which are located in different anatomical localizations. In this case we report the utility of an intraoperative handheld gamma camera in the localization of epitrochlear drainage of distal upper extremity melanoma and its impact on surgical procedure. PMID:26550052

  18. Effects of Intraoperative Hemodynamics on Incidence of Postoperative Delirium in Elderly Patients: A Retrospective Study

    PubMed Central

    Yang, Lin; Sun, De-feng; Han, Jun; Liu, Ruochuan; Wang, Li-jie; Zhang, Zhen-zhen

    2016-01-01

    Background Postoperative delirium (POD) is a common complication in the elderly. This retrospective study investigated the effect of intraoperative hemodynamics on the incidence of POD in elderly patients after major surgery to explore ways to reduce the incidence of POD. Material/Methods Based on the incidence of POD, elderly patients (81±6 y) were assigned to a POD (n=137) or non-POD group (n=343) after elective surgery with total intravenous anesthesia. POD was diagnosed based on the guidelines of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), using the confusion assessment method. The hemodynamic parameters, such as mean arterial pressure, were monitored 10 min before anesthesia (baseline) and intraoperatively. The incidence of intraoperative hypertension, hypotension, tachycardia, and bradycardia were calculated. Results At 30 min and 60 min after the initiation of anesthesia and at the conclusion of surgery, the monitored hemodynamic parameter values of the POD group, but not those of the non-POD group, were significantly higher than at baseline. Multivariate logistic regression analysis showed that intraoperative hypertension and tachycardia were significantly associated with POD. Conclusions Intraoperative hypertension and tachycardia were significantly associated with POD. Maintaining intraoperative stable hemodynamics may reduce the incidence of POD in elderly patients undergoing surgery. PMID:27038856

  19. Predictive roles of intraoperative blood glucose for post-transplant outcomes in liver transplantation

    PubMed Central

    Park, Chul Soo

    2015-01-01

    Diabetogenic traits in patients undergoing liver transplantation (LT) are exacerbated intraoperatively by exogenous causes, such as surgical stress, steroids, blood transfusions, and catecholamines, which lead to intraoperative hyperglycemia. In contrast to the strict glucose control performed in the intensive care unit, no systematic protocol has been developed for glucose management during LT. Intraoperative blood glucose concentrations typically exceed 200 mg/dL in LT, and extreme hyperglycemia (> 300 mg/dL) is common during the neohepatic phase. Only a few retrospective studies have examined the relationship between intraoperative hyperglycemia and post-transplant complications, with reports of infectious complications or mortality. However, no prospective studies have been conducted regarding the influence of intraoperative hyperglycemia in LT on post-transplant outcome. In addition to absolute blood glucose values, the temporal patterns in blood glucose levels during LT may serve as prognostic features. Persistent neohepatic hyperglycemia (without a decline) throughout LT is a useful indicator of early graft dysfunction. Moreover, intraoperative variability in glucose levels may predict the need for reoperation for hemorrhage after LT. Thus, there is an urgent need for guidelines for glucose control in these patients, as well as prospective studies on the impact of glucose control on various post-transplant complications. This report highlights some of the recent studies related to perioperative blood glucose management focused on LT and liver disease. PMID:26078559

  20. Effects of Intraoperative Hemodynamics on Incidence of Postoperative Delirium in Elderly Patients: A Retrospective Study.

    PubMed

    Yang, Lin; Sun, De-Feng; Han, Jun; Liu, Ruochuan; Wang, Li-Jie; Zhang, Zhen-Zhen

    2016-01-01

    BACKGROUND Postoperative delirium (POD) is a common complication in the elderly. This retrospective study investigated the effect of intraoperative hemodynamics on the incidence of POD in elderly patients after major surgery to explore ways to reduce the incidence of POD. MATERIAL AND METHODS Based on the incidence of POD, elderly patients (81±6 y) were assigned to a POD (n=137) or non-POD group (n=343) after elective surgery with total intravenous anesthesia. POD was diagnosed based on the guidelines of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), using the confusion assessment method. The hemodynamic parameters, such as mean arterial pressure, were monitored 10 min before anesthesia (baseline) and intraoperatively. The incidence of intraoperative hypertension, hypotension, tachycardia, and bradycardia were calculated. RESULTS At 30 min and 60 min after the initiation of anesthesia and at the conclusion of surgery, the monitored hemodynamic parameter values of the POD group, but not those of the non-POD group, were significantly higher than at baseline. Multivariate logistic regression analysis showed that intraoperative hypertension and tachycardia were significantly associated with POD. CONCLUSIONS Intraoperative hypertension and tachycardia were significantly associated with POD. Maintaining intraoperative stable hemodynamics may reduce the incidence of POD in elderly patients undergoing surgery. PMID:27038856

  1. Utility of Intraoperative Neuromonitoring during Minimally Invasive Fusion of the Sacroiliac Joint

    PubMed Central

    Woods, Michael; Birkholz, Denise; MacBarb, Regina; Capobianco, Robyn; Woods, Adam

    2014-01-01

    Study Design. Retrospective case series. Objective. To document the clinical utility of intraoperative neuromonitoring during minimally invasive surgical sacroiliac joint fusion for patients diagnosed with sacroiliac joint dysfunction (as a direct result of sacroiliac joint disruptions or degenerative sacroiliitis) and determine stimulated electromyography thresholds reflective of favorable implant position. Summary of Background Data. Intraoperative neuromonitoring is a well-accepted adjunct to minimally invasive pedicle screw placement. The utility of intraoperative neuromonitoring during minimally invasive surgical sacroiliac joint fusion using a series of triangular, titanium porous plasma coated implants has not been evaluated. Methods. A medical chart review of consecutive patients treated with minimally invasive surgical sacroiliac joint fusion was undertaken at a single center. Baseline patient demographics and medical history, intraoperative electromyography thresholds, and perioperative adverse events were collected after obtaining IRB approval. Results. 111 implants were placed in 37 patients. Sensitivity of EMG was 80% and specificity was 97%. Intraoperative neuromonitoring potentially avoided neurologic sequelae as a result of improper positioning in 7% of implants. Conclusions. The results of this study suggest that intraoperative neuromonitoring may be a useful adjunct to minimally invasive surgical sacroiliac joint fusion in avoiding nerve injury during implant placement. PMID:25544898

  2. Multimodality intraoperative neurophysiological monitoring during Onyx embolization of cerebrovascular malformations.

    PubMed

    Deshaies, Eric M; Singla, Amit; Allott, Geoffrey; Villwock, Mark R; Li, Fenghua; Gorji, Reza

    2015-03-01

    General anesthesia prohibits neurological examination during embolization of cerebrovascular malformations when provocative testing prior to pedicle occlusion is needed. Intraoperative neurophysiological monitoring (IONM) has the potential to fill this gap but remains relatively unexplored. We conduct a retrospective review of consecutive patients with cerebrovascular malformations treated with Onyx (ethylene vinyl alcohol copolymer, dissolved in dimethyl sulfoxide) embolization under general anesthesia with IONM from 2009 to 2012. Somatosensory evoked potentials (SSEPs), transcranial motor evoked potentials (TcMEPs), visual evoked potential (VEPs), auditory brainstem response (ABR), and electroencephalography (EEG) were used selectively in all patients depending on the location of the malformation. Provocative testing combined with IONM was performed in 28 patients over 75 sessions. Three patients demonstrated changes in TcMEPs or ABR during provocative testing, which halted the planned embolization. Two patients demonstrated changes in baseline SSEPs after embolization, despite normal IONM during provocative testing, correlating with postprocedural contralateral weakness. Six patients developed visual deficits after arterial occlusion despite unchanged VEPs and occipital EEG during provocative testing and embolization. We therefore conclude that the sensitivity of TcMEPs and SSEPs is preferable to EEG, and we strongly caution against relying on occipital recorded VEPs to predict visual deficits. PMID:26036117

  3. The Value of Intraoperative OCT Imaging in Vitreoretinal Surgery

    PubMed Central

    Ehlers, Justis P.; Tao, Yuankai K.; Srivastava, Sunil K.

    2014-01-01

    Purpose of review To evaluate the role of intraoperative OCT (iOCT) in vitreoretinal surgery, assess the current state-of-the art and to examine possible future directions in the field. Recent findings Numerous vitreoretinal surgical conditions and procedures have been described utilizing iOCT. These conditions include macular holes, epiretinal membranes, retinal detachments, and retinopathy of prematurity. Significant alterations appear to occur during surgical manipulations in many of these conditions that can be identified with iOCT. The most common current systems used are portable OCT probes that are either mounted to a microscope or used in a handheld fashion. Prototypes are also being utilized that are integrated into the microscope to allow for true “real-time” imaging of instrument-tissue interactions. Current generation surgical instrument materials (e.g., metal) limit optimal visualization with integrated OCT systems due to shadowing and light scattering properties. Summary The role of iOCT in vitreoretinal surgery continues to be defined by active research and enhancements to integrative technologies. Further research is needed to better define the specific applications of iOCT that impact patient outcomes and surgical decision-making. Future advancements in integrative systems, OCT-friendly instrumentation, and software algorithms will further expand the horizon of iOCT in the vitreoretinal surgical theater. As OCT transformed the clinical management of the vitreoretinal conditions, iOCT has the potential to be a paradigm-shifting technology in the operating room. PMID:24614147

  4. Intraoperative surgical photoacoustic microscopy (IS-PAM) using augmented reality

    NASA Astrophysics Data System (ADS)

    Lee, Changho; Han, Seunghoon; Kim, Sehui; Jeon, Mansik; Kim, Jeehyun; Kim, Chulhong

    2014-03-01

    We have developed an intraoperative surgical photoacoustic microscopy (IS-PAM) system by integrating an optical resolution photoacoustic microscopy (OR-PAM) and conventional surgical microscope. Based on the common optical path in the OR-PAM and microscope system, we can acquire the PAM and microscope images at the same time. Furthermore, by utilizing a mini-sized beam projector, 2D PAM images are back-projected onto the microscope view plane as augmented reality. Thus, both the conventional microscopic and 2D cross-sectional PAM images are displayed on the plane through an eyepiece lens of the microscope. In our method, additional image display tool is not required to show the PAM image. Therefore, it potentially offers significant convenience to surgeons without movement of their sights during surgeries. In order to demonstrate the performance of our IS-PAM system, first, we successfully monitored needle intervention in phantoms. Moreover, we successfully guided needle insertion into mice skins in vivo by visualizing surrounding blood vessels from the PAM images and the magnified skin surfaces from the conventional microscopic images simultaneously.

  5. Contralateral ulnar neuropathy following total hip replacement and intraoperative positioning.

    PubMed

    O'Brien, S; Bennett, D; Spence, D J; Mawhinney, I; Beverland, D E

    2016-05-01

    Peripheral neuropathy is a rare but important complication of total hip arthroplasty (THA) and has previously been reported in the ipsilateral arm and associated with inflammatory arthritis. The results of 7004 primary hip arthroplasties performed between January 1993 and February 2009 were retrospectively reviewed to identify patients who reported ulnar neuropathy symptoms, with ten patients identified at mean follow-up of 57 months (range = 3-195 months). Eight patients experienced unilateral ulnar nerve symptoms in the contralateral upper limb post-surgery, one patient experienced symptoms in the ipsilateral upper limb and one patient experienced symptoms in both upper limbs. The incidence of post-THA ulnar neuropathy was 0.14%. All patients had a pre-operative diagnosis of osteoarthritis and none had diabetes, a previous history of neuropathy or inflammatory arthritis. All operations were primary arthroplasties and were performed under the care of a single surgeon in a single centre. Two of the ten patients (20%) had a general anaesthetic. The pattern of symptoms reported, i.e. mainly unilateral affecting the contralateral side with variable resolution, contrasts with previous studies and suggests that intraoperative patient positioning may be an important factor influencing ulnar neuropathy following THA. Attention to support and positioning of the contralateral arm may help reduce the incidence of this complication. PMID:26589446

  6. Risk factors for intraoperative hypotension during thyroid surgery

    PubMed Central

    Kalezic, Nevena; Stojanovic, Marina; Ladjevic, Nebojsa; Markovic, Dejan; Paunovic, Ivan; Palibrk, Ivan; Milicic, Biljana; Sabljak, Vera; Antonijevic, Vesna; Ivanovic, Branislava; Ugrinovic, Djordje; Zivaljevic, Vladan

    2013-01-01

    Background Hypotension is a common adverse effect of IV anaesthetics, especially during the induction of anaesthesia. The aim of our study was to determine the incidence and risk factors for intraoperative hypotension (IOH) in thyroid surgery, as well as to determine whether and to what extent IOH affects the occurrence of postoperative hypotension. Material/Methods The study included 1252 euthyroid patients, ASA 2 and ASA 3 status (American Society of Anesthesiologists physical status classification), who had thyroid surgery between 2007 and 2011. IOH was defined as a decrease in systolic blood pressure of >20% of baseline values. We studied the influence of demographic characteristics (sex, age, body mass index-BMI), comorbidity, type and duration of surgery, and anaesthesia on the occurrence of IOH. Univariate and multivariate logistic regression were used to determine predictors of occurrence of IOH. Results IOH was registered in 6.5% of patients. The most common operation was thyroidectomy. Patients with IOH were younger, had lower BMI, and significantly less often had hypertension as a coexisting disease. The multivariate regression model identified BMI and the absence of hypertension as a coexisting disease, and as independent predictors of occurrence of IOH. Significantly more patients with IOH had postoperative hypotension (9.9% vs. 2.4%, p=0.000). Conclusions IOH is common, even during operations of short duration and with minimal bleeding. It is necessary to pay special attention to these patients, given that many of these patients remained hypotensive during the postoperative period. PMID:23548975

  7. Intraoperative Conversion to ALPPS in a Case of Intrahepatic Cholangiocarcinoma

    PubMed Central

    Oldhafer, F.; Ringe, K. I.; Timrott, K.; Kleine, M.; Ramackers, W.; Cammann, S.; Jäger, M. D.; Klempnauer, J.; Bektas, H.; Vondran, F. W. R.

    2015-01-01

    Background. Surgical resection remains the best treatment option for intrahepatic cholangiocarcinoma (ICC). Two-stage liver resection combining in situ liver transection with portal vein ligation (ALPPS) has been described as a promising method to increase the resectability of liver tumors also in the case of ICC. Presentation of Case. A 46-year-old male patient presented with an ICC-typical lesion in the right liver. The indication for primary liver resection was set and planed as a right hepatectomy. In contrast to the preoperative CT-scan, the known lesion showed further progression in a macroscopically steatotic liver. Therefore, the decision was made to perform an ALPPS-procedure to avoid an insufficient future liver remnant (FLR). The patient showed an uneventful postoperative course after the first and second step of the ALPPS-procedure, with sufficient increase of the FLR. Unfortunately, already 2.5 months after resection the patient had developed new tumor lesions found by the follow-up CT-scan. Discussion. The presented case demonstrates that an intraoperative conversion to an ALPPS-procedure is safely applicable when the FLR surprisingly seems to be insufficient. Conclusion. ALPPS should also be considered a treatment option in well-selected patients with ICC. However, the experience concerning the outcome of ALPPS in case of ICC remains fairly small. PMID:26649219

  8. Mammographic findings after intraoperative radiotherapy of the breast.

    PubMed

    Rivera, Ronald; Smith-Bronstein, Virginia; Villegas-Mendez, Sylvia; Rayhanabad, Jessica; Sheth, Pulin; Rashtian, Afshin; Holmes, Dennis R

    2012-01-01

    Intraoperative Radiotherapy (IORT) is a form of accelerated partial breast radiation that has been shown to be equivalent to conventional whole breast external beam radiotherapy (EBRT) in terms of local cancer control. However, questions have been raised about the potential of f IORT to produce breast parenchymal changes that could interfere with mammographic surveillance of cancer recurrence. The purpose of this study was to identify, quantify, and compare the mammographic findings of patients who received IORT and EBRT in a prospective, randomized controlled clinical trial of women with early stage invasive breast cancer undergoing breast conserving therapy between July 2005 and December 2009. Treatment groups were compared with regard to the 1, 2 and 4-year incidence of 6 post-operative mammographic findings: architectural distortion, skin thickening, skin retraction, calcifications, fat necrosis, and mass density. Blinded review of 90 sets of mammograms of 15 IORT and 16 EBRT patients demonstrated a higher incidence of fat necrosis among IORT recipients at years 1, 2, and 4. However, none of the subjects were judged to have suspicious mammogram findings and fat necrosis did not interfere with mammographic interpretation. PMID:22550585

  9. An orthopedic tissue adhesive for targeted delivery of intraoperative biologics.

    PubMed

    Simson, Jacob; Crist, Joshua; Strehin, Iossif; Lu, Qiaozhi; Elisseeff, Jennifer H

    2013-03-01

    Tissue adhesives can bind together damaged tissues and serve as tools to deliver and localize therapeutics to facilitate regeneration. One emerging therapeutic trend in orthopedics is the use of intraoperative biologics (IOB), such as bone marrow (BM) and platelet-rich plasma (PRP), to stimulate healing. Here, we introduce the application of the biomaterial chondroitin sulfate succinimidyl succinate (CS-NHS) to deliver IOB in a hydrogel adhesive. We demonstrate the biomaterial's ability to bind various tissue types and its cellular biocompatibility with encapsulated human mesenchymal stem cells (hMSCs). Further, we examine in detail the CS-NHS adhesive combined with BM aspirate for use in bone applications. hMSCs were encapsulated in CS-BM and cultured for 5 weeks in osteogenic medium. Quantitative RT-PCR demonstrated osteogenesis via upregulation of the osteogenic transcription factor Runx2 and bone markers alkaline phosphatase and osteocalcin. Significant deposition of calcium and osteocalcin was detected using biochemical, histological, and immunohistochemical techniques. Shear testing demonstrated that the CS-BM adhesive exhibited an adhesive strength approximately an order of magnitude stronger than fibrin glue and approaching that of a cyanoacrylate adhesive. These results indicate that CS-NHS is a promising delivery tool for IOB in orthopedic applications requiring a strong, degradable, and biocompatible adhesive that supports bone growth. PMID:23097279

  10. Intraoperative Squash Cytologic Features of Subependymal Giant Cell Astrocytoma

    PubMed Central

    Nasit, Jitendra; Vaghsiya, Viren; Hiryur, Srilaxmi; Patel, Smita

    2016-01-01

    Subependymal giant cell astrocytoma (SEGA) is a low grade (WHO Grade I) tumor, usually seen in patients with tuberous sclerosis complex and commonly occurs at a lateral ventricular location. Intraoperative squash cytologic features can help in differentiating SEGA from gemistocytic astrocytoma (GA), giant cell glioblastoma and ependymoma, in proper clinical context and radiological findings, which may alter the surgical management. Here, we present a case of SEGA with squash cytologic findings and a review of cytology findings of SEGA presently available in the literature. Loose cohesive clusters of large polygonal cells containing an eccentric nucleus, evenly distributed granular chromatin, distinct to prominent nucleoli, and moderate to the abundant eosinophilic cytoplasm in a hair-like fibrillar background are the key cytologic features of SEGA. Other important features are moderate anisonucleosis and frequent binucleation and multinucleation. The absence of mitoses, necrosis, and vascular endothelial proliferation are important negative features. Other consistent features are cellular smears, few dispersed cells, few spindly strap-like cells, rare intranuclear cytoplasmic inclusion, and perivascular pseudorosettes. PMID:27013816

  11. Intra-operative contrast echocardiography in coronary artery disease.

    PubMed

    Voci, P

    1992-08-01

    Intra-operative echocardiography is becoming a reference standard for the evaluation of the results of cardiac surgery. Myocardial contrast echocardiography has been recently introduced to study regional myocardial blood flow and cardioplegia distribution in patients undergoing coronary artery surgery. It can be used in three different stages: before cardiopulmonary bypass, to identify the most hypoperfused myocardial segments; during cardioplegic arrest, to check the adequacy of myocardial protection; postoperatively, to assess graft patency. The priority in revascularization can be assigned according to the regional perfusion pattern, which depends not only on coronary artery narrowing, but also on the extent of collateral circulation. The distribution of cardioplegia to the myocardium can be monitored in real time with clear identification of poorly protected myocardial segments. The injection in the graft after weaning from cardiopulmonary bypass allows assessment of graft patency and measurement of the 'area at risk' for graft occlusion. In conclusion, the information obtained in the operating theatre by myocardial contrast echocardiography is original and promises to have a significant impact on surgical strategy. Implementation of the ultrasonic equipment to obtain quantitative on-line data on myocardial blood flow is desirable. PMID:1505566

  12. Multimodal correlation and intraoperative matching of virtual models in neurosurgery

    NASA Technical Reports Server (NTRS)

    Ceresole, Enrico; Dalsasso, Michele; Rossi, Aldo

    1994-01-01

    The multimodal correlation between different diagnostic exams, the intraoperative calibration of pointing tools and the correlation of the patient's virtual models with the patient himself, are some examples, taken from the biomedical field, of a unique problem: determine the relationship linking representation of the same object in different reference frames. Several methods have been developed in order to determine this relationship, among them, the surface matching method is one that gives the patient minimum discomfort and the errors occurring are compatible with the required precision. The surface matching method has been successfully applied to the multimodal correlation of diagnostic exams such as CT, MR, PET and SPECT. Algorithms for automatic segmentation of diagnostic images have been developed to extract the reference surfaces from the diagnostic exams, whereas the surface of the patient's skull has been monitored, in our approach, by means of a laser sensor mounted on the end effector of an industrial robot. An integrated system for virtual planning and real time execution of surgical procedures has been realized.

  13. Intraoperative and external beam irradiation for locally advanced colorectal cancer.

    PubMed Central

    Gunderson, L L; Martin, J K; Bart, R W; Nagorney, D M; Fieck, J M; Wieand, H S; Martinez, A; O'Connell, M J; Martenson, J A; McIlrath, D C

    1988-01-01

    In view of poor local control rates obtained with standard treatment, intraoperative radiation (IORT) using electrons was combined with external beam irradiation and surgical resection, with or without 5-fluorouracil (5FU), in 51 patients with locally advanced colorectal cancer (recurrent, 36 patients; primary, 15 patients). Patients received 4500-5500 cGy (rad) of fractionated, multiple field external beam irradiation and an IORT dose of 1000-2000 cGy. Thirty of 51 patients (59%) are alive and 22 patients (43%) are free of disease. In 44 patients at risk greater than or equal to 1 year, local progression within the IORT field has occurred in 1 of 44 (2%) and within the external beam field in 8 of 44 (18%). All local failures have occurred in patients with recurrence or with gross residual after partial resection, and the risk was less in patients who received 5FU during external irradiation (1 of 11, 9% vs. 6 of 31, 19%). The incidence of distant metastases is high in patients with recurrence, but subsequent peritoneal failures are infrequent. Acute and chronic tolerance have been acceptable, but peripheral nerve appears to be a dose-limiting structure. Randomized trials are needed to determine whether potential gains with IORT are real. PMID:3337561

  14. Intraoperative Conversion to ALPPS in a Case of Intrahepatic Cholangiocarcinoma.

    PubMed

    Oldhafer, F; Ringe, K I; Timrott, K; Kleine, M; Ramackers, W; Cammann, S; Jäger, M D; Klempnauer, J; Bektas, H; Vondran, F W R

    2015-01-01

    Background. Surgical resection remains the best treatment option for intrahepatic cholangiocarcinoma (ICC). Two-stage liver resection combining in situ liver transection with portal vein ligation (ALPPS) has been described as a promising method to increase the resectability of liver tumors also in the case of ICC. Presentation of Case. A 46-year-old male patient presented with an ICC-typical lesion in the right liver. The indication for primary liver resection was set and planed as a right hepatectomy. In contrast to the preoperative CT-scan, the known lesion showed further progression in a macroscopically steatotic liver. Therefore, the decision was made to perform an ALPPS-procedure to avoid an insufficient future liver remnant (FLR). The patient showed an uneventful postoperative course after the first and second step of the ALPPS-procedure, with sufficient increase of the FLR. Unfortunately, already 2.5 months after resection the patient had developed new tumor lesions found by the follow-up CT-scan. Discussion. The presented case demonstrates that an intraoperative conversion to an ALPPS-procedure is safely applicable when the FLR surprisingly seems to be insufficient. Conclusion. ALPPS should also be considered a treatment option in well-selected patients with ICC. However, the experience concerning the outcome of ALPPS in case of ICC remains fairly small. PMID:26649219

  15. Intraoperative severe hypoglycemia indicative of post-hepatectomy liver failure.

    PubMed

    Chung, Kyudon; Bang, Seunguk; Kim, Yoona; Chang, Hyuntae

    2016-02-01

    We present the first reported case of a patient with intraoperative hypoglycemia, with no predisposing factors, that was indicative of post-hepatectomy liver failure due to liver injury. A 56-year-old man was hospitalized to undergo left lateral segmentectomy, cholecystectomy and T-tube choledocholithotripsy due to calculi in the intrahepatic and common bile ducts. His medical history was unremarkable. Three hours after surgery initiation, his glucose level decreased from 84 mg/dL to below detectable levels. We infused 20 % dextrose repeatedly until his glucose level returned to within normal limits. His aspartate aminotransferase and alanine aminotransferase levels increased to over 10,000 IU/L, and his blood urea nitrogen and creatinine levels increased postoperatively. Thus, we diagnosed post-hepatectomy liver failure and hepatorenal syndrome and treated the patient conservatively. This case illustrates that, if no other causative factors for severe hypoglycemia occurring during liver resection are present, the anesthesiologist should predict post-hepatectomy liver failure due to liver injury and inform the surgeon in order to enable rapid evaluation and treatment. PMID:26329532

  16. Intraoperative visualization and assessment of electromagnetic tracking error

    NASA Astrophysics Data System (ADS)

    Harish, Vinyas; Ungi, Tamas; Lasso, Andras; MacDonald, Andrew; Nanji, Sulaiman; Fichtinger, Gabor

    2015-03-01

    Electromagnetic tracking allows for increased flexibility in designing image-guided interventions, however it is well understood that electromagnetic tracking is prone to error. Visualization and assessment of the tracking error should take place in the operating room with minimal interference with the clinical procedure. The goal was to achieve this ideal in an open-source software implementation in a plug and play manner, without requiring programming from the user. We use optical tracking as a ground truth. An electromagnetic sensor and optical markers are mounted onto a stylus device, pivot calibrated for both trackers. Electromagnetic tracking error is defined as difference of tool tip position between electromagnetic and optical readings. Multiple measurements are interpolated into the thin-plate B-spline transform visualized in real time using 3D Slicer. All tracked devices are used in a plug and play manner through the open-source SlicerIGT and PLUS extensions of the 3D Slicer platform. Tracking error was measured multiple times to assess reproducibility of the method, both with and without placing ferromagnetic objects in the workspace. Results from exhaustive grid sampling and freehand sampling were similar, indicating that a quick freehand sampling is sufficient to detect unexpected or excessive field distortion in the operating room. The software is available as a plug-in for the 3D Slicer platforms. Results demonstrate potential for visualizing electromagnetic tracking error in real time for intraoperative environments in feasibility clinical trials in image-guided interventions.

  17. Intraoperative electron-beam radiotherapy and ureteral obstruction

    SciTech Connect

    Miller, Robert C.; Haddock, Michael G.; Petersen, Ivy A.; Gunderson, Leonard L.; Furth, Alfred F.

    2006-03-01

    Purpose: To quantify the risk of ureteral obstruction (UO) after intraoperative electron-beam radiotherapy (IOERT). Methods and Materials: One hundred forty-six patients received IOERT of 7.5 to 30 Gy to 168 ureters; 132 patients received external radiotherapy. Results: Follow-up ranged from 0.01 to 19.1 years (median, 2.1 years). The rates of clinically apparent type 1 UO (UO from any cause) after IOERT at 2, 5, and 10 years were 47%, 63%, and 79%, respectively. The rates of clinically apparent type 2 UO (UO occurring at least 1 month after IOERT, excluding UO caused by tumor or abscess and patients with stents) at 2, 5, and 10 years were 27%, 47%, and 70%, respectively. Multivariate analysis revealed that the presence of UO before IOERT (p < 0.001) was associated with an increased risk of clinically apparent type 1 UO. Increasing IOERT dose (p < 0.04) was associated with an increased risk of clinically apparent type 2 UO. UO rates in ureters not receiving IOERT at 2, 5, and 10 years were 19%, 19%, and 51%, respectively. Conclusions: Risk of UO after IOERT increases with dose. However, UO risk for ureters not receiving IOERT was also high, which suggests an underlying risk of ureteral injury from other causes.

  18. Intraoperative localization of brachytherapy implants using intensity-based registration

    NASA Astrophysics Data System (ADS)

    KarimAghaloo, Z.; Abolmaesumi, P.; Ahmidi, N.; Chen, T. K.; Gobbi, D. G.; Fichtinger, G.

    2009-02-01

    In prostate brachytherapy, a transrectal ultrasound (TRUS) will show the prostate boundary but not all the implanted seeds, while fluoroscopy will show all the seeds clearly but not the boundary. We propose an intensity-based registration between TRUS images and the implant reconstructed from fluoroscopy as a means of achieving accurate intra-operative dosimetry. The TRUS images are first filtered and compounded, and then registered to the fluoroscopy model via mutual information. A training phantom was implanted with 48 seeds and imaged. Various ultrasound filtering techniques were analyzed, and the best results were achieved with the Bayesian combination of adaptive thresholding, phase congruency, and compensation for the non-uniform ultrasound beam profile in the elevation and lateral directions. The average registration error between corresponding seeds relative to the ground truth was 0.78 mm. The effect of false positives and false negatives in ultrasound were investigated by masking true seeds in the fluoroscopy volume or adding false seeds. The registration error remained below 1.01 mm when the false positive rate was 31%, and 0.96 mm when the false negative rate was 31%. This fully automated method delivers excellent registration accuracy and robustness in phantom studies, and promises to demonstrate clinically adequate performance on human data as well.

  19. Policy implications of greenhouse warming

    SciTech Connect

    Not Available

    1991-01-01

    Contents: background; the greenhouse gases and their effects; policy framework; adaptation; mitigation; international considerations; findings and conclusions; recommendations; questions and answers about greenhouse warming; background information on synthesis panel members and professional staff; and membership lists for effects, mitigation, and adaptation panels.

  20. Comparative effect of intraoperative propacetamol versus placebo on morphine consumption after elective reduction mammoplasty under remifentanil-based anesthesia: a randomized control trial [ISRCTN71723173

    PubMed Central

    Binhas, Michèle; Decailliot, François; Rezaiguia-Delclaux, Saïda; Suen, Powen; Dumerat, Marc; François, Véronique; Combes, Xavier; Duvaldestin, Philippe

    2004-01-01

    Background Postoperative administration of paracetamol or its prodrug propacetamol has been shown to decrease pain with a morphine sparing effect. However, the effect of propacetamol administered intra-operatively on post-operative pain and early postoperative morphine consumption has not been clearly evaluated. In order to evaluate the effectiveness of analgesic protocols in the management of post-operative pain, a standardized anesthesia protocol without long-acting opioids is crucial. Thus, for ethical reasons, the surgical procedure under general anesthesia with remifentanil as the only intraoperative analgesic must be associated with a moderate predictable postoperative pain. Methods We were interested in determining the postoperative effect of propacetamol administered intraoperatively after intraoperative remifentanil. Thirty-six adult women undergoing mammoplasty with remifentanil-based anesthesia were randomly assigned to receive propacetamol 2 g or placebo one hour before the end of surgery. After remifentanil interruption and tracheal extubation in recovery room, pain was assessed and intravenous titrated morphine was given. The primary end-point was the cumulative dose of morphine administered in the recovery room. The secondary end-points were the pain score after tracheal extubation and one hour after, the delay for obtaining a Simplified Numerical Pain Scale (SNPS) less than 4, and the incidence of morphine side effects in the recovery room. For intergroup comparisons, categorical variables were compared using the chi-squared test and continuous variables were compared using the Student t test or Mann-Whitney U test, as appropriate. A p value less than 0.05 was considered as significant. Results In recovery room, morphine consumption was lower in the propacetamol group than in the placebo group (p = 0.01). Pain scores were similar in both groups after tracheal extubation and lower in the propacetamol group (p = 0.003) one hour after tracheal extubation. The time to reach a SNPS < 4 was significantly shorter in the propacetamol group (p = 0.02). The incidence of morphine related side effects did not differ between the two groups. Conclusions Intraoperative propacetamol administration with remifentanil based-anesthesia improved significantly early postoperative pain by sparing morphine and shortening the delay to achieve pain relief. PMID:15367329

  1. Equatorial refuge amid tropical warming

    NASA Astrophysics Data System (ADS)

    Karnauskas, Kristopher B.; Cohen, Anne L.

    2012-07-01

    Upwelling across the tropical Pacific Ocean is projected to weaken in accordance with a reduction of the atmospheric overturning circulation, enhancing the increase in sea surface temperature relative to other regions in response to greenhouse-gas forcing. In the central Pacific, home to one of the largest marine protected areas and fishery regions in the global tropics, sea surface temperatures are projected to increase by 2.8C by the end of this century. Of critical concern is that marine protected areas may not provide refuge from the anticipated rate of large-scale warming, which could exceed the evolutionary capacity of coral and their symbionts to adapt. Combining high-resolution satellite measurements, an ensemble of global climate models and an eddy-resolving regional ocean circulation model, we show that warming and productivity decline around select Pacific islands will be mitigated by enhanced upwelling associated with a strengthening of the equatorial undercurrent. Enhanced topographic upwelling will act as a negative feedback, locally mitigating the surface warming. At the Gilbert Islands, the rate of warming will be reduced by 0.7+/-0.3C or 25+/-9% per century, or an overall cooling effect comparable to the local anomaly for a typical El Nio, by the end of this century. As the equatorial undercurrent is dynamically constrained to the Equator, only a handful of coral reefs stand to benefit from this equatorial island effect. Nevertheless, those that do face a lower rate of warming, conferring a significant advantage over neighbouring reef systems. If realized, these predictions help to identify potential refuges for coral reef communities from anticipated climate changes of the twenty-first century.

  2. Association Between Cholecystectomy With vs Without Intraoperative Cholangiography and Risk of Common Duct Injury

    PubMed Central

    Sheffield, Kristin M.; Riall, Taylor S.; Han, Yimei; Kuo, Yong-Fang; Townsend, Courtney M.; Goodwin, James S.

    2014-01-01

    IMPORTANCE Significant controversy exists regarding routine intraoperative cholangiography in preventing common duct injury during cholecystectomy. OBJECTIVE To investigate the association between intraoperative cholangiography use during cholecystectomy and common duct injury. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort study of all Texas Medicare claims data from 2000 through 2009. We identified Medicare beneficiaries 66 years or older who underwent inpatient or outpatient cholecystectomy for biliary colic or biliary dyskinesia, acute cholecystitis, or chronic cholecystitis. We compared results from multilevel logistic regression models to the instrumental variable analyses. INTERVENTIONS Intraoperative cholangiography use during cholecystectomy was determined at the level of the patients (yes/no), hospitals (percentage intraoperative cholangiography use for all cholecystectomies at the hospital), and surgeons (percentage use for all cholecystectomies performed by the surgeon). Percentage of use at the hospital and percentage of use by surgeon were the instrumental variables. MAIN OUTCOMES AND MEASURES Patients with claims for common duct repair operations within 1 year of cholecystectomy were considered as having major common duct injury. RESULTS Of 92 932 patients undergoing cholecystectomy, 37 533 (40.4%) underwent concurrent intraoperative cholangiography and 280 (0.30%) had a common duct injury. The common duct injury rate was 0.21% among patients with intraoperative cholangiography and 0.36% among patients without it. In a logistic regression model controlling for patient, surgeon, and hospital characteristics, the odds of common duct injury for cholecystectomies performed without intraoperative cholangiography were increased compared with those performed with it (OR, 1.79 [95% CI, 1.35–2.36]; P < .001). When confounding was controlled with instrumental variable analysis, the association between cholecystectomy performed without intraoperative cholangiography and duct injury was no longer significant (OR, 1.26 [95% CI, 0.81–1.96]; P = .31). CONCLUSIONS AND RELEVANCE When confounders were controlled with instrumental variable analysis, there was no statistically significant association between intraoperative cholangiography and common duct injury. Intraoperative cholangiography is not effective as a preventive strategy against common duct injury during cholecystectomy. PMID:23982367

  3. Intraoperative respiratory failure in a patient after treatment with bleomycin: previous and current intraoperative exposure to 50% oxygen.

    PubMed

    Luis, M; Ayuso, A; Martinez, G; Souto, M; Ortells, J

    1999-01-01

    Patients treated with bleomycin (BLM) are at risk of developing acute respiratory distress syndrome (ARDS) post-operatively, and this has been associated with high intraoperative concentrations of oxygen. We report progressive arterial desaturation noticeable 2 h after the start of a 4-h radical neck dissection for which the anaesthesia included 50% O2 in N2O. The patient had received two courses of bleomycin within the previous 2 months and had undergone an uneventful right hemiglossectomy under shorter but otherwise similar anaesthesia 4 weeks previously. His pulmonary function tests before the second procedure showed a slight depression of diffusing capacity (DLco) to 80% of predicted and minimal airway obstruction consistent with his history of smoking. The pulse oximetric reading during his second procedure reached 75%, but rose to 95% after treatment with methylprednisolone salbutamol and inspired O2 concentrations between 80% and 100%. By the end of the procedure, he satisfied the criteria for ARDS and was transferred to the ICU, where he developed bilateral pneumonia, deteriorated and died of multiple organ failure. This case suggests that the risk of hyperoxic pulmonary damage in patients exposed to bleomycin may increase not only with the degree and duration of hyperoxia in a given exposure, but also with the latent effects of recent previous exposure. Near normality of pulmonary function tests cannot be taken as reassurance, and small changes may have more adverse prognostic significance than in patients who have not been exposed to bleomycin. PMID:10084104

  4. Catching a Cold When It's Warm

    MedlinePlus

    ... please review our exit disclaimer . Subscribe Catching a Cold When It’s Warm What’s the Deal with Summertime ... what could be more unfair than catching a cold when it’s warm? How can cold symptoms arise ...

  5. Warming trends: Adapting to nonlinear change

    SciTech Connect

    Jonko, Alexandra K.

    2015-01-28

    As atmospheric carbon dioxide concentrations rise, some regions are expected to warm more than others. Research suggests that whether warming will intensify or slow down over time also depends on location.

  6. Trophic mismatch requires seasonal heterogeneity of warming.

    PubMed

    Straile, Dietmar; Kerimoglu, Onur; Peeters, Frank

    2015-10-01

    Climate warming has been shown to advance the phenology of species. Asynchronous changes in phenology between interacting species may disrupt feeding interactions (phenological mismatch), which could have tremendous consequences for ecosystem functioning. Long-term field observations have suggested asynchronous shifts in phenology with warming, whereas experimental studies have not been conclusive. Using proxy-based modeling of three trophic levels (algae, herbivores, and fish), we .show that asynchronous changes in phenology only occur if warming is seasonally heterogeneous, but not if warming is constant throughout the year. If warming is seasonally heterogeneous, the degree and even direction of asynchrony depends on the specific seasonality of the warming. Conclusions about phenological mismatches in food web interactions may therefore produce controversial results if the analyses do not distinguish between seasonally constant and seasonal specific warming. Furthermore, our results suggest that predicting asynchrony between interacting species requires reliable warming predictions that resolve sub-seasonal time scales. PMID:26649399

  7. Arctic climate change: Greenhouse warming unleashed

    NASA Astrophysics Data System (ADS)

    Mauritsen, Thorsten

    2016-04-01

    Human activity alters the atmospheric composition, which leads to global warming. Model simulations suggest that reductions in emission of sulfur dioxide from Europe since the 1970s could have unveiled rapid Arctic greenhouse gas warming.

  8. Integration of intraoperative and model-updated images into an industry-standard neuronavigation system: initial results

    NASA Astrophysics Data System (ADS)

    Schaewe, Timothy J.; Fan, Xiaoyao; Ji, Songbai; Hartov, Alex; Hiemenz Holton, Leslie; Roberts, David W.; Paulsen, Keith D.; Simon, David A.

    2013-03-01

    Dartmouth and Medtronic have established an academic-industrial partnership to develop, validate, and evaluate a multimodality neurosurgical image-guidance platform for brain tumor resection surgery that is capable of updating the spatial relationships between preoperative images and the current surgical field. Previous studies have shown that brain shift compensation through a modeling framework using intraoperative ultrasound and/or visible light stereovision to update preoperative MRI appears to result in improved accuracy in navigation. However, image updates have thus far only been produced retrospective to surgery in large part because of gaps in the software integration and information flow between the co-registration and tracking, image acquisition and processing, and image warping tasks which are required during a case. This paper reports the first demonstration of integration of a deformation-based image updating process for brain shift modeling with an industry-standard image guided surgery platform. Specifically, we have completed the first and most critical data transfer operation to transmit volumetric image data generated by the Dartmouth brain shift modeling process to the Medtronic StealthStation® system. StealthStation® comparison views, which allow the surgeon to verify the correspondence of the received updated image volume relative to the preoperative MRI, are presented, along with other displays of image data such as the intraoperative 3D ultrasound used to update the model. These views and data represent the first time that externally acquired and manipulated image data has been imported into the StealthStation® system through the StealthLink® portal and visualized on the StealthStation® display.

  9. Does intraoperative neurophysiologic monitoring matter in noncomplex spine surgeries?

    PubMed Central

    van der Goes, David N.; Nuwer, Marc R.

    2015-01-01

    Objectives: To determine associations between intraoperative neurophysiologic monitoring (IOM) for spinal decompressions and simple fusions with neurologic complications, length of stay, and hospitalization charges. Methods: Adult discharges in the Nationwide/National Inpatient Sample (NIS) (2007–2012) with spinal decompressions and simple spinal fusions were included. Revision surgeries, instrumentations, complicated approaches, and tumor- and trauma-related surgeries were excluded. Extracted data included patient demographics, medical comorbidities, primary spinal surgery type, and hospital characteristics. Bivariate and multiple regression analyses using NIS survey design variables correlated IOM use with neurologic complications, hospital charges, and length of stay. Results: IOM was reported in 4.9% of an estimated 1.1 million discharges in the weighted sample. Discharges reporting IOM were more often privately insured (61% vs 57%, p < 0.001) and had slightly more comorbidities (25% vs 24% with 3+ comorbidities, p = 0.01). Spinal fusions more often reported IOM than decompressions. The IOM group had fewer neurologic complications (0.8% vs 1.4% of controls) with no difference in length of stay (3.0 days for each group), but increased hospital charges (39% greater). Multiple regression adjustment showed significant associations of IOM with fewer neurologic complications (odds ratio 0.60, 95% confidence interval [CI] 0.47, 0.76, p < 0.001), while the estimated percentage of hospital charges was sizably diminished from the unadjusted analysis (IOM effect +9%, 95% CI +4%, +13%, p < 0.001), and length of stay was reduced (IOM effect −0.26 days, 95% CI −0.42, −0.11, p < 0.001). Conclusions: IOM was associated with better clinical outcomes and some increased hospital charges among discharges of simple spinal fusions and laminectomies in a large, multiyear, nationally representative dataset. PMID:26446062

  10. Intraoperative Near-Infrared Imaging Can Identify Pulmonary Nodules

    PubMed Central

    Okusanya, Olugbenga T.; Holt, David; Heitjan, Daniel; Deshpande, Charuhas; Venegas, Ollin; Jiang, Jack; Judy, Ryan; DeJesus, Elizabeth; Madajewski, Brian; Oh, Kenny; Albelda, Steven M.; Nie, Shuming; Singhal, Sunil

    2014-01-01

    Background Over 80,000 people undergo pulmonary resection for a lung nodule in the United States each year. Small nodules are frequently missed or difficult to find despite preoperative imaging. We hypothesized that near-infrared (NIR) imaging technology could be used to identify and locate lung nodules during surgery. Methods We enrolled 18 patients who were diagnosed with a pulmonary nodule that required resection. All patients had a fine-cut 1mm computed tomography scan preoperatively. The patients were given systemic 5 mg/kg indocyanine green (ICG) and then underwent an open thoracotomy 24 hours later. NIR imaging was used to identify the primary nodule and search for additional nodules that were not found by visual inspection or manual palpation of the ipsilateral lung. Results Manual palpation and visual inspection identified all 18 primary pulmonary nodules and no additional lesions. Intraoperative NIR imaging detected 16 out of the 18 primary nodules. NIR imaging also identified 5 additional subcentimeter nodules: 3 metastatic adenocarcinomas and 2 metastatic sarcomas. This technology could identify nodules as small as 0.2 cm and as deep as 1.3 cm from the pleural surface. This approach discovered 3 nodules that were in different lobes than the primary tumor. Nodule fluorescence was independent of size, metabolic activity, histology, tumor grade and vascularity. Conclusions This is the first-in-human demonstration of identifying pulmonary nodules during Thoracic surgery with NIR imaging without a priori knowledge of their location or existence. NIR imaging can detect pulmonary nodules during lung resections that are poorly visualized on computed tomography and difficult to discriminate on finger palpation. PMID:25106680

  11. Morphometric analysis of cryofixed muscular tissue for intraoperative consultation.

    PubMed

    Bianciardi, Giorgio; Pontenani, Francesca; Vassallo, Loretta; Tacchini, Damiana; Buonsanti, Michele; Tripodi, Sergio

    2016-03-01

    For diagnostic purposes, cryofixation of tissues is a daily routine technique to investigate rapidly about the presence of tumours during a surgical procedure in patients. We performed morphometric analysis of cryofixed muscular tissues according to different techniques. About 1,000 muscle fibers and 1,493 nuclei, were automatically examined. After freezing, ice tissue interfaces shrinkage of the cells were present. Liquid isopentane or liquid nitrogen produced a statistical increase of fractal dimension, D, of the ice-tissue interfaces, P < 0.001 respect to the formalin-fixed samples, cryofixation performed inside the cryostat chamber at t = -20°C produced a D value close to the formalin-fixed samples. Shrinkage of the muscle fibers was higher in the samples cryofixed inside the cryostat chamber (P < 0.001). Cryofixation inside cryostat or by liquid nitrogen caused decreases of the nuclei dimensions and altered nuclear morphology (P < 0.01), liquid isopentane appeared not affecting the nuclei of the fibers. Cryofixation inside the cryostat chamber produced the highest shrinkage but it was reduced performing cryofixation in liquid nitrogen or isopentane. Freezing damage inside the muscle cells was absent in the samples cryofixed inside the cryostat, it was present after cryofixation by liquid nitrogen or isopentane. Subcellular components like the nuclei were preserved by isopentane. This paper present, for the first time, an objective method able to quantify and characterize the damages produced by cryofixation in biological sample for intraoperative consultation. Microsc. Res. Tech. 79:155-161, 2016. © 2016 Wiley Periodicals, Inc. PMID:26910641

  12. Intraoperative detection of differentiated thyroid carcinoma using iodine-131

    SciTech Connect

    Ricard, M.; Travagli, J.P.; Lumbroso, J.

    1996-05-01

    We evaluated the contribution of intraoperative detection when patients with differentiated thyroid carcinoma where reoperated for neck and mediastinal lymph node metastases. Twenty seven patients who had a positive scan underwent further surgery 50 to 6 days after a therapeutic administration of 4 GBq {approx} 100 mCi of iodine-131. We used the {open_quotes}Gammed 2{close_quotes} device provided by CIS biointernational (Gif-sur-Yvette, France); the probe consists of a cylinder 3 cm in diameter and 13.5 cm in length and is based on a CsI scintillator detector (O = 1 cm ; L = 1 cm). In order to minimize the influence of the non-specific uptake and to improve the spatial resolution, we used a tungsten collimator. The atomic number (55-53) and the density ({approx} 6 g cm{sup -3}) of the scintillator allowed a good detection efficiency ({approx} 2 cts s{sup -1} kBq{sup -1}). The FWHM in air is about 1 cm at 1 cm distance from an iodine-131 point source. Activity in blood and surrounding tissues was used as a reference level. The tumor count rate ranged from 50 to more than 1000 cts s{sup -1}. The ratios between tumoral and normal tissue were always higher than 3 and the surgeon considered the method helpful for localizing lymph node metastases in 18/27 surgical procedures. The preoperative detection was considered only partially contributory in 9 cases : in 6 patients post-operative scintigraphy remained positive ; in 3 patients the surgeon also removed metastatic lymph nodes with no detectable iodine-131 uptake. This method provides the surgeon with an additional tool able to distinguish between normal and tumoral tissue, even if the energy of iodine 131 (364 keV) is not optimal for short range localization. In order will be designed with a modified shape and a more efficient shielding, particularly with respect to background activity.

  13. Intraoperative Radiotherapy for Parotid Cancer: A Single-Institution Experience

    SciTech Connect

    Zeidan, Youssef H.; Shiue, Kevin; Weed, Daniel; Johnstone, Peter A.; Terry, Colin; Freeman, Stephen; Krowiak, Edward; Borrowdale, Robert; Huntley, Tod; Yeh, Alex

    2012-04-01

    Purpose: Our practice policy has been to provide intraoperative radiotherapy (IORT) at resection to patients with head-and-neck malignancies considered to be at high risk of recurrence. The purpose of the present study was to review our experience with the use of IORT for primary or recurrent cancer of the parotid gland. Methods and Materials: Between 1982 and 2007, 96 patients were treated with gross total resection and IORT for primary or recurrent cancer of the parotid gland. The median age was 62.9 years (range, 14.3-88.1). Of the 96 patients, 33 had previously undergone external beam radiotherapy as a component of definitive therapy. Also, 34 patients had positive margins after surgery, and 40 had perineural invasion. IORT was administered as a single fraction of 15 or 20 Gy with 4-6-MeV electrons. The median follow-up period was 5.6 years. Results: Only 1 patient experienced local recurrence, 19 developed regional recurrence, and 12 distant recurrence. The recurrence-free survival rate at 1, 3, and 5 years was 82.0%, 68.5%, and 65.2%, respectively. The 1-, 3-, and 5-year overall survival rate after surgery and IORT was 88.4%, 66.1%, and 56.2%, respectively. No perioperative fatalities occurred. Complications developed in 26 patients and included vascular complications in 7, trismus in 6, fistulas in 4, radiation osteonecrosis in 4, flap necrosis in 2, wound dehiscence in 2, and neuropathy in 1. Of these 26 patients, 12 had recurrent disease, and 8 had undergone external beam radiotherapy before IORT. Conclusions: IORT results in effective local disease control at acceptable levels of toxicity and should be considered for patients with primary or recurrent cancer of the parotid gland.

  14. Intraoperative radiotherapy with electrons: fundamentals, results, and innovation

    PubMed Central

    Calvo, FA; Sole, CV; Herranz, R; Lopez-Bote, M; Pascau, J; Santos, A; Muñoz-Calero, A; Ferrer, C; Garcia-Sabrido, JL

    2013-01-01

    Rationale and objectives To analyse the programme activity and clinical innovation and/or technology developed over a period of 17 years with regard to the introduction and the use of intraoperative radiotherapy (IORT) as a therapeutic component in a medical–surgical multidisciplinary cancer hospital. Material and methods To standardise and record this procedure, the Radiation Oncology service has an institutional programme and protocols that must be completed by the different specialists involved. For 17 years, IORT procedures were recorded on a specific database that includes 23 variables with information recorded on institutional protocols. As part of the development and innovation activity, two technological tools were implemented (RADIANCE and MEDTING) in line with the standardisation of this modality in clinical practice. Results During the 17 years studied, 1,004 patients were treated through 1,036 IORT procedures. The state of the disease at the time of IORT was 77% primary and 23% recurrent. The origin and distribution of cancers were 62% gastrointestinal, 18% sarcomas, 5% pancreatic, 2% paediatric, 3% breast, 7% less common locations, and 2% others. The research and development projects have generated a patent on virtual planning (RADIANCE) and proof of concept to explore as a professional social network (MEDTING). During 2012, there were 69 IORT procedures. There was defined treatment volume (target or target region) in all of them, and 43 were conducted by the virtual planning RADIANCE system. Eighteen have been registered on the platform MEDTING as clinical cases. Conclusion The IORT programme, developed in a university hospital with an academic tradition, and interdisciplinary surgical oncology, is a feasible care initiative, able to generate the necessary intense clinical activity for tending to the cancer patient. Moreover, it is a competitive source for research, development, and scientific innovation. PMID:24009641

  15. Laparoscopic Intraoperative Ultrasonography, Color Doppler, and Power Flow Application.

    PubMed

    Jakimowicz; Stultiëns

    1997-06-01

    The applications of color Doppler and power flow imaging for laparoscopic intraoperative ultrasonography (LIOU) are discussed. Basic principles concerning Doppler, color Doppler imaging (CDI), and power flow (PF) are briefly reviewed, and a number of representative examples of imaging are provided. LIOU is progressively gaining importance, not only for screening of the biliary tract, but in particular, for staging laparoscopy in patients with gastrointestinal cancer. The CDI technology that was developed relatively quickly is now in widespread use in diagnostic ultrasound, particularly for vascular surgery. CD options are no longer restricted to the expensive high-end ultrasound scanners, but are available in the majority of modest duplex systems with limited additional costs. Ongoing developments in ultrasound technology have resulted in the introduction of an alternative option to mean frequency-based CD ultrasound, ie, the PF. There are several advantages that emanate from the combination of B-mode ultrasound with CDI and/or PF. These include (1) rapid identification of anatomical structures, ie, vessels, ducts, tissue spaces, and cysts; (2) detection of small vessels that are difficult or impossible to recognize by B-mode scanning alone; (3) more accurate assessment of vascular encasement/involvement by tumor and a precise display of major vessels anatomically related to the tumor; (4) real-time guidance for safe parenchymal dissection of solid organs with identification and preservation of blood supply; (5) precise guided needle biopsy or puncture; and (6) visualization of bile flow in common bile by PF. This has the potential to enable dynamic flow studies of the function of the papilla of Vater in the near future. PMID:10401148

  16. Variation in the Use of Intraoperative Cholangiography during Cholecystectomy

    PubMed Central

    Sheffield, Kristin M; Han, Yimei; Kuo, Yong-Fang; Townsend, Courtney M; Goodwin, James S; Riall, Taylor S

    2012-01-01

    Background The role of intraoperative cholangiography (IOC) in prevention of common bile duct (CBD) injuries and the management of CBD stones is controversial, and current variation in use of IOC has not been well described. Study Design Multilevel hierarchical models using data from the Texas Hospital Inpatient Discharge Public Use data files (2001–2008) were used to evaluate the percentage of variance in the use of IOC that was attributable to patient, surgeon, and hospital factors. Results A total of 176,981 cholecystectomies were performed in 212 hospitals in Texas. There was wide variation in IOC use, ranging from 2.4% to 98.4% of cases among surgeons and 3.7% to 94.8% of cases among hospitals, even after adjusting for case mix differences. The percentage of variance in IOC use attributable to the surgeon was 20.7% and an additional 25.7% was attributable to the hospital. IOC use was associated with increased age, gallstone pancreatitis or CBD stones, Hispanic race, decreased illness severity, insurance, and later year of cholecystectomy. ERCP (24.0% vs. 14.9%, P<0.0001) and CBD exploration (1.63% vs. 0.42%, P<0.0001) were more commonly performed in patients undergoing IOC. Conclusions Uncertainty regarding the benefit of IOC leads to wide variation in use across surgeons and hospitals. The surgeon and hospital are more important determinants of IOC use than patient characteristics. Our study highlights the need for further evaluation of comparative effectiveness of IOC in the prevention of CBD injuries and retained stones taking into account patient risk factors, surgeon skill, cost, and availability of local expertise. PMID:22366491

  17. Intraoperative Electron Radiotherapy for the Management of Aggressive Fibromatosis

    SciTech Connect

    Roeder, Falk; Timke, Carmen; Oertel, Susanne; Hensley, Frank W.; Bischof, Marc; Muenter, Marc W.; Weitz, Juergen; Buchler, Markus W.; Lehner, Burkhard; Debus, Juergen; Krempien, Robert

    2010-03-15

    Purpose: We analyzed our experience with intraoperative electron radiotherapy (IOERT) followed by moderate doses of external beam radiotherapy (EBRT) after organ-sparing surgery in patients with primary or recurrent aggressive fibromatosis. Methods and Materials: Indication for IOERT and postoperative EBRT as an individual treatment approach to avoid mutilating surgical procedures was seen when complete surgical removal seemed to be unlikely or impossible. A total of 31 lesions in 30 patients were treated by surgery and IOERT with a median dose of 12 Gy. Median age was 31 years (range, 13-59 years). Resection status was close margin in six lesions, microscopically positive in 13, and macroscopically positive in 12. Median tumor size was 9 cm. In all, 25 patients received additional EBRT, with a median dose of 45 Gy (range, 36-54 Gy). Results: After a median follow-up of 32 months (range, 3-139 months), no disease-related deaths occurred. A total of five local recurrences were seen, resulting in actuarial 3-year local control rates of 82% overall and 91% inside the IOERT areas. Trends to improved local control were seen for older age (>31 years) and negative margins, but none of these factors reached significance. Perioperative complications were found in six patients, in particular as wound healing disturbances in five patients and venous thrombosis in one patient. Late toxicity was seen in five patients. Conclusion: Introduction of IOERT into a multimodal treatment approach in patients with aggressive fibromatosis is feasible with low toxicity and yielded good local control rates even in patients with microscopical or gross residual disease.

  18. Intraoperative bleeding control by uniportal video-assisted thoracoscopic surgery†.

    PubMed

    Gonzalez-Rivas, Diego; Stupnik, Tomaz; Fernandez, Ricardo; de la Torre, Mercedes; Velasco, Carlos; Yang, Yang; Lee, Wentao; Jiang, Gening

    2016-01-01

    Owing to advances in video-assisted thoracic surgery (VATS), the majority of pulmonary resections can currently be performed by VATS in a safe manner with a low level of morbidity and mortality. The majority of the complications that occur during VATS can be minimized with correct preoperative planning of the case as well as careful pulmonary dissection. Coordination of the whole surgical team is essential when confronting an emergency such as major bleeding. This is particularly important during the VATS learning curve, where the occurrence of intraoperative complications, particularly significant bleeding, usually ends in a conversion to open surgery. However, conversion should not be considered as a failure of the VATS approach, but as a resource to maintain the patient's safety. The correct assessment of any bleeding is of paramount importance during major thoracoscopic procedures. Inadequate management of the source of bleeding may result in major vessel injury and massive bleeding. If bleeding occurs, a sponge stick should be readily available to apply pressure immediately to control the haemorrhage. It is always important to remain calm and not to panic. With the bleeding temporarily controlled, a decision must be made promptly as to whether a thoracotomy is needed or if the bleeding can be solved through the VATS approach. This will depend primarily on the surgeon's experience. The operative vision provided with high-definition cameras, specially designed or adapted instruments and the new sealants are factors that facilitate the surgeon's control. After experience has been acquired with conventional or uniportal VATS, the rate of complications diminishes and the majority of bleeding events are controlled without the need for conversion to thoracotomy. PMID:26424873

  19. Quantification of tumor fluorescence during intraoperative optical cancer imaging

    PubMed Central

    Judy, Ryan P.; Keating, Jane J.; DeJesus, Elizabeth M.; Jiang, Jack X.; Okusanya, Olugbenga T.; Nie, Shuming; Holt, David E.; Arlauckas, Sean P.; Low, Phillip S.; Delikatny, E. James; Singhal, Sunil

    2015-01-01

    Intraoperative optical cancer imaging is an emerging technology in which surgeons employ fluorophores to visualize tumors, identify tumor-positive margins and lymph nodes containing metastases. This study compares instrumentation to measure tumor fluorescence. Three imaging systems (Spectropen, Glomax, Flocam) measured and quantified fluorescent signal-to-background ratios (SBR) in vitro, murine xenografts, tissue phantoms and clinically. Evaluation criteria included the detection of small changes in fluorescence, sensitivity of signal detection at increasing depths and practicality of use. In vitro, spectroscopy was superior in detecting incremental differences in fluorescence than luminescence and digital imaging (Ln[SBR] = 6.8 ± 0.6, 2.4 ± 0.3, 2.6 ± 0.1, p = 0.0001). In fluorescent tumor cells, digital imaging measured higher SBRs than luminescence (6.1 ± 0.2 vs. 4.3 ± 0.4, p = 0.001). Spectroscopy was more sensitive than luminometry and digital imaging in identifying murine tumor fluorescence (SBR = 41.7 ± 11.5, 5.1 ± 1.8, 4.1 ± 0.9, p = 0.0001), and more sensitive than digital imaging at detecting fluorescence at increasing depths (SBR = 7.0 ± 3.4 vs. 2.4 ± 0.5, p = 0.03). Lastly, digital imaging was the most practical and least time-consuming. All methods detected incremental differences in fluorescence. Spectroscopy was the most sensitive for small changes in fluorescence. Digital imaging was the most practical considering its wide field of view, background noise filtering capability, and sensitivity to increasing depth. PMID:26563091

  20. Intraoperative positioning of mobile C-arms using artificial fluoroscopy

    NASA Astrophysics Data System (ADS)

    Dressel, Philipp; Wang, Lejing; Kutter, Oliver; Traub, Joerg; Heining, Sandro-Michael; Navab, Nassir

    2010-02-01

    In trauma and orthopedic surgery, imaging through X-ray fluoroscopy with C-arms is ubiquitous. This leads to an increase in ionizing radiation applied to patient and clinical staff. Placing these devices in the desired position to visualize a region of interest is a challenging task, requiring both skill of the operator and numerous X-rays for guidance. We propose an extension to C-arms for which position data is available that provides the surgeon with so called artificial fluoroscopy. This is achieved by computing digitally reconstructed radiographs (DRRs) from pre- or intraoperative CT data. The approach is based on C-arm motion estimation, for which we employ a Camera Augmented Mobile C-arm (CAMC) system, and a rigid registration of the patient to the CT data. Using this information we are able to generate DRRs and simulate fluoroscopic images. For positioning tasks, this system appears almost exactly like conventional fluoroscopy, however simulating the images from the CT data in realtime as the C-arm is moved without the application of ionizing radiation. Furthermore, preoperative planning can be done on the CT data and then visualized during positioning, e.g. defining drilling axes for pedicle approach techniques. Since our method does not require external tracking it is suitable for deployment in clinical environments and day-to-day routine. An experiment with six drillings into a lumbar spine phantom showed reproducible accuracy in positioning the C-arm, ranging from 1.1 mm to 4.1 mm deviation of marker points on the phantom compared in real and virtual images.

  1. Intraoperative Sac Pressure Measurement During Endovascular Abdominal Aortic Aneurysm Repair

    SciTech Connect

    Ishibashi, Hiroyuki; Ishiguchi, Tsuneo; Ohta, Takashi; Sugimoto, Ikuo; Iwata, Hirohide; Yamada, Tetsuya; Tadakoshi, Masao; Hida, Noriyuki; Orimoto, Yuki; Kamei, Seiji

    2010-10-15

    PurposeIntraoperative sac pressure was measured during endovascular abdominal aortic aneurysm repair (EVAR) to evaluate the clinical significance of sac pressure measurement.MethodsA microcatheter was placed in an aneurysm sac from the contralateral femoral artery, and sac pressure was measured during EVAR procedures in 47 patients. Aortic blood pressure was measured as a control by a catheter from the left brachial artery.ResultsThe systolic sac pressure index (SPI) was 0.87 {+-} 0.10 after main-body deployment, 0.63 {+-} 0.12 after leg deployment (P < 0.01), and 0.56 {+-} 0.12 after completion of the procedure (P < 0.01). Pulse pressure was 55 {+-} 21 mmHg, 23 {+-} 15 mmHg (P < 0.01), and 16 {+-} 12 mmHg (P < 0.01), respectively. SPI showed no significant differences between the Zenith and Excluder stent grafts (0.56 {+-} 0.13 vs. 0.54 {+-} 0.10, NS). Type I endoleak was found in seven patients (15%), and the SPI decreased from 0.62 {+-} 0.10 to 0.55 {+-} 0.10 (P = 0.10) after fixing procedures. Type II endoleak was found in 12 patients (26%) by completion angiography. The SPI showed no difference between type II endoleak positive and negative (0.58 {+-} 0.12 vs. 0.55 {+-} 0.12, NS). There were no significant differences between the final SPI of abdominal aortic aneurysms in which the diameter decreased in the follow-up and that of abdominal aortic aneurysms in which the diameter did not change (0.53 {+-} 0.12 vs. 0.57 {+-} 0.12, NS).ConclusionsSac pressure measurement was useful for instant hemodynamic evaluation of the EVAR procedure, especially in type I endoleaks. However, on the basis of this small study, the SPI cannot be used to reliably predict sac growth or regression.

  2. The Role of Transesophageal Echocardiography in the Intraoperative Period

    PubMed Central

    Gouveia, Verónica; Marcelino, Paulo; Reuter, Daniel A

    2011-01-01

    The goal of hemodynamic monitoring and management during major surgery is to guarantee adequate organ perfusion, a major prerequisite for adequate tissue oxygenation and thus, end-organ function. Further, hemodynamic monitoring should serve to prevent, detect, and to effectively guide treatment of potentially life-threatening hemodynamic events, such as severe hypovolemia due to hemorrhage, or cardiac failure. The ideal monitoring device does not exist, but some conditions must be met: it should be easy and operator-independently to use; it should provide adequate, reproducible information in real time. In this review we discuss in particular the role of intraoperative use of transesophageal echocardiography (TOE). Although TOE has gained special relevance in cardiac surgery, its role in major non cardiac surgery is still to be determined. We particularly focus on its ability to provide measurements of cardiac output (CO), and its role to guide fluid therapy. Within the last decade, concepts oriented on optimizing stroke volume and cardiac output mainly by fluid administration and guided by continuous monitoring of cardiac output or so called functional parameters of cardiac preload gained particular attention. Although they are potentially linked to an increased amount of fluid infusion, recent data give evidence that such pre-emptive concepts of hemodynamic optimization result in a decrease in morbidity and mortality. As TOE allows a real time direct visualization of cardiac structures, other potentially important advantages of its use also outside the cardiac surgery operation room can be postulated, namely the ability to evaluate the anatomical and functional integrity of the left and the right heart chambers. Finally, a practical approach to TOE monitoring is presented, based on a local experience. PMID:22758616

  3. Label-free Intraoperative Parathyroid Localization With Near-Infrared Autofluorescence Imaging

    PubMed Central

    Paras, Constantine; White, Lisa M.; Phay, John E.; Solórzano, Carmen C.; Broome, James T.; Mahadevan-Jansen, Anita

    2014-01-01

    Context: The inability to accurately localize the parathyroid glands during parathyroidectomy and thyroidectomy procedures can prevent patients from achieving postoperative normocalcemia. There is a critical need for an improved intraoperative method for real-time parathyroid identification. Objective: The objective of the study was to test the accuracy of a real-time, label-free technique that uses near-infrared (NIR) autofluorescence imaging to localize the parathyroid. Setting: The study was conducted at the Vanderbilt University endocrine surgery center. Subjects and Methods: Patients undergoing parathyroidectomy and/or thyroidectomy were included in this study. To validate the intrinsic fluorescence signal in parathyroid, point measurements from 110 patients were collected using NIR fluorescence spectroscopy. Fluorescence imaging was performed on 6 patients. Imaging contrast is based on a previously unreported intrinsic NIR fluorophore in the parathyroid gland. The accuracy of fluorescence imaging was analyzed in comparison with visual assessment and histological findings. Main Outcome Measure: The detection rate of parathyroid glands was measured. Results: The parathyroid glands in 100% of patients measured with fluorescence imaging were successfully detected in real time. Fluorescence images consistently showed 2.4 to 8.5 times higher emission intensity from the parathyroid than surrounding tissue. Histological validation confirmed that the high intrinsic fluorescence signal in the parathyroid gland can be used to localize the parathyroid gland regardless of disease state. Conclusion: NIR fluorescence imaging represents a highly sensitive, real-time, label-free tool for parathyroid localization during surgery. The elegance and effectiveness of NIR autofluorescence imaging of the parathyroid gland makes it highly attractive for clinical application in endocrine surgery. PMID:25148235

  4. Intraoperative Radiotherapy for Pancreatic Cancer: 30-Year Experience in a Single Institution in Japan

    SciTech Connect

    Jingu, Keiichi; Tanabe, Takaya; Nemoto, Kenji; Ariga, Hisanori; Umezawa, Rei; Ogawa, Yoshihiro; Takeda, Ken; Koto, Masashi; Sugawara, Toshiyuki; Kubozono, Masaki; Shimizu, Eiji; Abe, Keiko; Yamada, Shogo

    2012-07-15

    Purpose: To analyze retrospectively the results of intraoperative radiotherapy (IORT) with or without external beam radiotherapy ({+-} EBRT) for localized pancreatic cancer in the past three decades and to analyze prognostic factors by multivariate analysis. Methods and Materials: Records for 322 patients with pancreatic cancer treated by IORT {+-} EBRT in Tohoku University Hospital between 1980 and 2009 were reviewed. One hundred ninety-two patients who had no distant organ metastases or dissemination at the time of laparotomy were enrolled in the present study. Results: Eighty-three patients underwent gross total resection (R0: 48 patients, R1: 35 patients), and 109 patients underwent only biopsy or palliative resection. Fifty-five patients underwent adjuvant EBRT, and 124 underwent adjuvant chemotherapy. The median doses of IORT and EBRT were 25 and 40 Gy, respectively. The median follow-up period was 37.5 months. At the time of the analysis, 166 patients had disease recurrence, and 35 patients had local failure. The 2-year local control (LC) and overall survival (OS) rates were 71.0% and 16.9%, respectively. Comparison of the results for each decade showed that OS was significantly improved decade by decade (2-year: 25.0% vs. 18.8% vs. 4.2%, p < 0.001). Multivariate analysis showed that degree of resection (R0-1 vs. R2, hazard ratio = 1.97, p = 0.001) and adjuvant chemotherapy (yes vs. no, hazard ratio = 1.54, p = 0.028) had significant impacts on OS. Late gastrointestinal morbidity of Common Terminology Criteria for Adverse Events version 3.0 grade 4 or 5 was observed in four patients. Conclusion: Excellent local control for pancreatic cancer with few cases of severe late toxicity was achieved by using IORT. OS of patients with pancreatic cancer treated by IORT {+-} EBRT improved significantly decade by decade. Multivariate analysis showed that degree of resection and adjuvant chemotherapy had significant impacts on OS.

  5. Use of Intraoperative Computed Tomography in Complex Craniofacial Trauma: An Example of On-Table Change in Management

    PubMed Central

    Morrison, Clinton S.; Taylor, Helena O.; Collins, Scott; Oyelese, Adetokunbo; Sullivan, Stephen R.

    2014-01-01

    The primary goals in repairing complex craniofacial fractures are restoration of occlusion and mastication, and anatomic reconstruction of a symmetric facial skeleton. Failure to accomplish these goals may result in the need for secondary operations. Recognition of malreduction may not be appreciated until review of a postoperative computed tomographic (CT) scan. Intraoperative CT scanning enables immediate on-table assessment of reduction and fixation, allowing alteration of the surgical plan as needed. We report using intraoperative CT scanning while repairing a panfacial injury in which malreduction was appreciated intraoperatively and corrected. Intraoperative CT can be used to improve outcomes and quality of complex facial fracture repair. PMID:25383151

  6. Carbon cycle and climate warming

    SciTech Connect

    Kerr, R.A.

    1983-12-09

    The increase in carbon dioxide in the atmosphere is expected to cause a warming of the earth. This increase is due to the fact that more carbon is released into the atmosphere than is removed by the biota and the oceans. Understanding the carbon cycle is important in predicting future warming. A major uncertainty is the timing and magnitude of future releases of CO/sub 2/ from the burning of fossil fuels. Today, 1.1 tons of carbon as CO/sub 2/ are released every year for every person on Earth. Estimates are given on how much CO/sub 2/ has been released into the atmosphere since fossil fuels have been burned. The ultimate aim of carbon cycle research is to predict how the concentration of CO/sub 2/ in the atmosphere will vary as mankind pumps more and more of it into the atmosphere.

  7. Lagrangian description of warm plasmas

    NASA Technical Reports Server (NTRS)

    Kim, H.

    1970-01-01

    Efforts are described to extend the averaged Lagrangian method of describing small signal wave propagation and nonlinear wave interaction, developed by earlier workers for cold plasmas, to the more general conditions of warm collisionless plasmas, and to demonstrate particularly the effectiveness of the method in analyzing wave-wave interactions. The theory is developed for both the microscopic description and the hydrodynamic approximation to plasma behavior. First, a microscopic Lagrangian is formulated rigorously, and expanded in terms of perturbations about equilibrium. Two methods are then described for deriving a hydrodynamic Lagrangian. In the first of these, the Lagrangian is obtained by velocity integration of the exact microscopic Lagrangian. In the second, the expanded hydrodynamic Lagrangian is obtained directly from the expanded microscopic Lagrangian. As applications of the microscopic Lagrangian, the small-signal dispersion relations and the coupled mode equations are derived for all possible waves in a warm infinite, weakly inhomogeneous magnetoplasma, and their interactions are examined.

  8. Hydrological consequences of global warming

    SciTech Connect

    Miller, Norman L.

    2009-06-01

    The 2007 Intergovernmental Panel for Climate Change indicates there is strong evidence that the atmospheric concentration of carbon dioxide far exceeds the natural range over the last 650,000 years, and this recent warming of the climate system is unequivocal, resulting in more frequent extreme precipitation events, earlier snowmelt runoff, increased winter flood likelihoods, increased and widespread melting of snow and ice, longer and more widespread droughts, and rising sea level. The effects of recent warming has been well documented and climate model projections indicate a range of hydrological impacts with likely to very likely probabilities (67 to 99 percent) of occurring with significant to severe consequences in response to a warmer lower atmosphere with an accelerating hydrologic cycle.

  9. Multidecadal warming of Antarctic waters.

    PubMed

    Schmidtko, Sunke; Heywood, Karen J; Thompson, Andrew F; Aoki, Shigeru

    2014-12-01

    Decadal trends in the properties of seawater adjacent to Antarctica are poorly known, and the mechanisms responsible for such changes are uncertain. Antarctic ice sheet mass loss is largely driven by ice shelf basal melt, which is influenced by ocean-ice interactions and has been correlated with Antarctic Continental Shelf Bottom Water (ASBW) temperature. We document the spatial distribution of long-term large-scale trends in temperature, salinity, and core depth over the Antarctic continental shelf and slope. Warming at the seabed in the Bellingshausen and Amundsen seas is linked to increased heat content and to a shoaling of the mid-depth temperature maximum over the continental slope, allowing warmer, saltier water greater access to the shelf in recent years. Regions of ASBW warming are those exhibiting increased ice shelf melt. PMID:25477461

  10. Analysis of data from spacecraft (stratospheric warmings)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The details of the stratospheric warming processes as to time, area, and intensity were established, and the warmings with other terrestrial and solar phenomena occurring at satellite platform altitudes, or observable from satellite platforms, were correlated. Links were sought between the perturbed upper atmosphere (mesosphere and thermosphere) and the stratosphere that might explain stratospheric warmings.

  11. Is the world warming or not?

    SciTech Connect

    Kerr, R.A.

    1995-02-03

    Articles in the popular press indicate controversy surrounding the reality of global warming. However greenhouse models predict more warming that is presently apparent. For climate change to live up to predictions, the minimal warming of the 1980`s will have to accelerate into the next millenium.

  12. Global warming: Economic policy responses

    SciTech Connect

    Dornbusch, R.; Poterba, J.M.

    1991-01-01

    This volume contains the proceedings of a conference that brought together economic experts from Europe, the US, Latin America, and Japan to evaluate key issues in the policy debate in global warming. The following issues are at the center of debates on alternative policies to address global warming: scientific evidence on the magnitude of global warming and the extent to which it is due to human activities; availability of economic tools to control the anthropogenic emissions of greenhouse gases, and how vigorously should they be applied; and political economy considerations which influence the design of an international program for controlling greenhouse gases. Many perspectives are offered on the approaches to remedying environmental problems that are currently being pursued in Europe and the Pacific Rim. Deforestation in the Amazon is discussed, as well as ways to slow it. Public finance assessments are presented of both the domestic and international policy issues raised by plans to levy a tax on the carbon emissions from various fossil fuels. Nine chapters have been processed separately for inclusion in the appropriate data bases.

  13. The Discovery of Global Warming

    NASA Astrophysics Data System (ADS)

    MacCracken, Michael C.

    2004-07-01

    At the beginning of the twentieth century, the prospect of ``global warming'' as a result of human activities was thought to be far off, and in any case, likely to be beneficial. As we begin the twenty-first century, science adviser to the British government, Sir David King, has said that he considers global warming to be the world's most important problem, including terrorism. Yet, dealing with it has become the subject of a contentious international protocol, numerous conferences of international diplomats, and major scientific assessments and research programs. Spencer Weart, who is director of the Center for History of Physics of the American Institute of Physics, has taken on the challenge of explaining how this came to be. In the tradition of the Intergovernmental Panel on Climate Change (IPCC), which was established in 1988 to evaluate and assess the state of global warming science, this book is roughly equivalent to the Technical Summary, in terms of its technical level, being quite readable, but with substantive content about the main lines of evidence. Underpinning this relatively concise presentation, there is a well-developed-and still developing-Web site that, like the detailed chapters of the full IPCC assessment reports, provides vastly more information and linkages to a much wider set of reference materials (see http://www.aip.org/history/climate).

  14. Intraoperative Tension Pneumothorax in a Patient With Remote Trauma and Previous Tracheostomy

    PubMed Central

    Mavarez-Martinez, Ana; Soghomonyan, Suren; Sandhu, Gurneet; Rankin, Demicha

    2016-01-01

    Many trauma patients present with a combination of cranial and thoracic injury. Anesthesia for these patients carries the risk of intraoperative hemodynamic instability and respiratory complications during mechanical ventilation. Massive air leakage through a lacerated lung will result in inadequate ventilation and hypoxemia and, if left undiagnosed, may significantly compromise the hemodynamic function and create a life-threatening situation. Even though these complications are more characteristic for the early phase of trauma management, in some cases, such a scenario may develop even months after the initial trauma. We report a case of a 25-year-old patient with remote thoracic trauma, who developed an intraoperative tension pneumothorax and hemodynamic instability while undergoing an elective cranioplasty. The intraoperative patient assessment was made even more challenging by unexpected massive blood loss from the surgical site. Timely recognition and management of intraoperative pneumothorax along with adequate blood replacement stabilized the patient and helped avoid an unfavorable outcome. This case highlights the risks of intraoperative pneumothorax in trauma patients, which may develop even months after injury. A high index of suspicion and timely decompression can be life saving in this type of situation. PMID:27006957

  15. Tissue tolerance of normal and surgically manipulated canine liver to intraoperative radiation therapy (IORT)

    SciTech Connect

    Chromheecke, M.; Oldhoff, J.; Hoekstra, H.J.; Vermeij, J.; Grond, A.J.K. ); Konings, A.W.T. )

    1993-12-01

    The purpose of the study is to obtain dose guidelines for the delivery of intraoperative radiotherapy to the liver of patients with colorectal liver metastases. Following partial resection of the liver, a single high dose of 10, 20, 25, and 30 Gy intraoperative radiotherapy was applied to both the resection plane as well as a nonsurgically manipulated part of the liver of 25 beagles. The temporal sequence of histological and ultrastructural changes of these irradiated parts of the liver tissue was investigated. The feasibility of delivering a single large dose of intraoperative electron beam radiotherapy to the normal and partially hepatectomized liver was experimentally investigated in a canine study. There were no postoperative complications, no morbidity or mortality with a minimal follow-up of 1 year. Autopsy performed 3 months following irradiation showed only mild histopathological changes. One year following intraoperative radiotherapy more distinct histopathological changes consisting of capsular thickening, diffuse parenchymal fibrosis and subcapsular hepatocellular atrophy were found. The liver function remained intact. This study demonstrated that intraoperative radiotherapy to part of the liver in the canine model can be safely applied and doses up to 30 Gy are well tolerated. 34 refs., 6 figs., 1 tab.

  16. Intraoperative cholangiography. A review of indications and analysis of age-sex groups.

    PubMed Central

    Levine, S B; Lerner, H J; Leifer, E D; Lindheim, S R

    1983-01-01

    A retrospective review was performed of patients who had biliary tract stone formation as the primary diagnosis for hospitalization and indication for surgery. Five hundred and eighty-nine consecutive charts were reviewed of patients admitted between 1975 and 1979. Intraoperative cholangiography was performed in 166 patients of whom 22 had common duct exploration. Choledochotomy in this series was performed in 63 cases without utilizing pre-exploratory cholangiography. A normal intraoperative cholangiogram was found to be 100% accurate; however, an abnormal cholangiogram was associated with a 16% false positive rate of exploration of the common duct. The incidence of unsuspected common duct stones detected only by intraoperative cholangiography was 2.3%. Age-sex analysis confirms a 10-year mean age difference between men and women within the population of this study (p less than 0.001). This age-sex difference is maintained in patients without common duct pathology as well as in patients with sterile bile. However, the mean age difference between male and female patients with either demonstrable common duct obstruction by stones or infected bile as determined by routine intraoperative culture is not statistically significant. A review of the role of intraoperative cholangiography, and the experience at Northeastern Hospital is discussed. PMID:6639173

  17. Warm Spray Forming of Ti-6Al-4V

    NASA Astrophysics Data System (ADS)

    Molak, R. M.; Araki, H.; Watanabe, M.; Katanoda, H.; Ohno, N.; Kuroda, S.

    2014-01-01

    Warm spray (WS) is a modification of high-velocity oxy-fuel spraying, in which the temperature of the supersonic gas flow generated by the combustion of kerosene and oxygen is controlled by diluting the combustion flame with an inert gas such as nitrogen. The inert gas is injected into the mixing chamber placed between the combustion chamber and the powder feed ports, thus the temperature of the propellant gas can be controlled from ~700 to 2,000 K. Since WS allows for higher particle temperatures in comparison to cold spray, warm sprayed particles are more softened upon impact, thus resulting in greater deformation facilitating the formation of shear instability for bonding. Recently, the combustion pressure of WS has been increased from 1 (low-pressure warm spray) to 4 MPa (high-pressure warm spray) in order to increase the velocity of sprayed particles. Effects of spray parameters on microstructure, mechanical properties, and splats formation of Ti-6Al-4V were systematically studied. Obtained coatings were examined by analyzing the coating cross-section images, microhardness as well as oxygen content. In addition, flattening ratio of splats was calculated as a function of nitrogen flow rate. It was found that the increased particle velocity caused by the increased combustion pressure had significant beneficial effects in terms of improving density and controlling the oxygen level in the sprayed Ti-6Al-4V coatings.

  18. Is intraoperative cholangiography necessary during laparoscopic cholecystectomy for cholelithiasis?

    PubMed Central

    Ding, Guo-Qian; Cai, Wang; Qin, Ming-Fang

    2015-01-01

    AIM: To determine the efficacy and safety benefits of performing intraoperative cholangiography (IOC) during laparoscopic cholecystectomy (LC) to treat symptomatic cholelithiasis. METHODS: Patients admitted to the Minimally Invasive Surgery Center of Tianjin Nankai Hospital between January 2012 and January 2014 for management of symptomatic cholelithiasis were recruited for this prospective randomized trial. Study enrollment was offered to patients with clinical presentation of biliary colic symptoms, radiological findings suggestive of gallstones, and normal serum biochemistry results. Study participants were randomized to receive either routine LC treatment or LC + IOC treatment. The routine LC procedure was carried out using the standard four-port technique; the LC + IOC procedure was carried out with the addition of meglumine diatrizoate (1:1 dilution with normal saline) injection via a catheter introduced through a small incision in the cystic duct made by laparoscopic scissors. Operative data and postoperative outcomes, including operative time, retained common bile duct (CBD) stones, CBD injury, other complications and length of hospital stay, were recorded for comparative analysis. Inter-group differences were statistically assessed by the ?2 test (categorical variables) and Fishers exact test (binary variables), with the threshold for statistical significance set at P < 0.05. RESULTS: A total of 371 patients were enrolled in the trial (late-adolescent to adult, age range: 16-70 years), with 185 assigned to the routine LC group and 186 to the LC + IOC group. The two treatment groups were similar in age, sex, body mass index, duration of symptomology, number and size of gallstones, and clinical symptoms. The two treatment groups also showed no significant differences in the rates of successful LC (98.38% vs 97.85%), CBD stone retainment (0.54% vs 0.00%), CBD injury (0.54% vs 0.53%) and other complications (2.16% vs 2.15%), as well as in duration of hospital stay (5.10 1.41 d vs 4.99 1.53 d). However, the LC + IOC treatment group showed significantly longer mean operative time (routine LC group: 43.00 4.15 min vs 52.86 4.47 min, P < 0.01). There were no cases of fatal complications in either group. At the one-year follow-up assessment, one patient in the routine LC group reported experiencing diarrhea for three months after the LC and one patient in the LC + IOC group reported on-going intermittent epigastric discomfort, but radiological examination provided no abnormal findings. CONCLUSION: IOC addition to the routine LC treatment of symptomatic cholelithiasis does not improve rates of CBD stone retainment or bile duct injury but lengthens operative time. PMID:25717250

  19. Quantitative wavelength analysis and image classification for intraoperative cancer diagnosis with hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Lu, Guolan; Qin, Xulei; Wang, Dongsheng; Chen, Zhuo Georgia; Fei, Baowei

    2015-03-01

    Complete surgical removal of tumor tissue is essential for postoperative prognosis after surgery. Intraoperative tumor imaging and visualization are an important step in aiding surgeons to evaluate and resect tumor tissue in real time, thus enabling more complete resection of diseased tissue and better conservation of healthy tissue. As an emerging modality, hyperspectral imaging (HSI) holds great potential for comprehensive and objective intraoperative cancer assessment. In this paper, we explored the possibility of intraoperative tumor detection and visualization during surgery using HSI in the wavelength range of 450 nm - 900 nm in an animal experiment. We proposed a new algorithm for glare removal and cancer detection on surgical hyperspectral images, and detected the tumor margins in five mice with an average sensitivity and specificity of 94.4% and 98.3%, respectively. The hyperspectral imaging and quantification method have the potential to provide an innovative tool for image-guided surgery.

  20. Serial FEM/XFEM-Based Update of Preoperative Brain Images Using Intraoperative MRI

    PubMed Central

    Vigneron, Lara M.; Noels, Ludovic; Warfield, Simon K.; Verly, Jacques G.; Robe, Pierre A.

    2012-01-01

    Current neuronavigation systems cannot adapt to changing intraoperative conditions over time. To overcome this limitation, we present an experimental end-to-end system capable of updating 3D preoperative images in the presence of brain shift and successive resections. The heart of our system is a nonrigid registration technique using a biomechanical model, driven by the deformations of key surfaces tracked in successive intraoperative images. The biomechanical model is deformed using FEM or XFEM, depending on the type of deformation under consideration, namely, brain shift or resection. We describe the operation of our system on two patient cases, each comprising five intraoperative MR images, and we demonstrate that our approach significantly improves the alignment of nonrigidly registered images. PMID:22287953

  1. Radical prostatectomy and intraoperative radiation therapy in high-risk prostate cancer.

    PubMed

    Marchioro, Giansilvio; Volpe, Alessandro; Tarabuzzi, Roberto; Apicella, Giuseppina; Krengli, Marco; Terrone, Carlo

    2012-01-01

    Intraoperative electron beam radiotherapy (IOERT) for prostate cancer (PC) is a radiotherapeutic technique, giving high doses of radiation during radical prostatectomy (RP). This paper presents the published treatment approaches for intraoperative radiotherapy analyzing functional outcome, morbidity, and oncological outcome in patients with clinical intermediate-high-risk prostate cancer. A systematic review of the literature was performed, searching PubMed and Web of Science. A "free text" protocol using the term intraoperative radiotherapy and prostate cancer was applied. Ten records were retrieved and analyzed including more than 150 prostate cancer patients treated with IOERT. IOERT represents a feasible technique with acceptable surgical time and minimal toxicity. A greater number of cases and longer follow-up time are needed in order to assess the long-term side effects and oncological outcome. PMID:22400019

  2. Radical Prostatectomy and Intraoperative Radiation Therapy in High-Risk Prostate Cancer

    PubMed Central

    Marchioro, Giansilvio; Volpe, Alessandro; Tarabuzzi, Roberto; Apicella, Giuseppina; Krengli, Marco; Terrone, Carlo

    2012-01-01

    Intraoperative electron beam radiotherapy (IOERT) for prostate cancer (PC) is a radiotherapeutic technique, giving high doses of radiation during radical prostatectomy (RP). This paper presents the published treatment approaches for intraoperative radiotherapy analyzing functional outcome, morbidity, and oncological outcome in patients with clinical intermediate-high-risk prostate cancer. A systematic review of the literature was performed, searching PubMed and Web of Science. A “free text” protocol using the term intraoperative radiotherapy and prostate cancer was applied. Ten records were retrieved and analyzed including more than 150 prostate cancer patients treated with IOERT. IOERT represents a feasible technique with acceptable surgical time and minimal toxicity. A greater number of cases and longer follow-up time are needed in order to assess the long-term side effects and oncological outcome. PMID:22400019

  3. Acute intraoperative neurogenic myocardial stunning during intracranial endoscopic fenestration and shunt revision in a pediatric patient.

    PubMed

    Dragan, Kristen Elizabeth; Patten, William D; Elzamzamy, Osama M; Attaallah, Ahmed Fikry

    2016-02-01

    Neurogenic stunned myocardium (NSM) is syndrome of myocardial dysfunction following an acute neurological insult. We report a case of NSM that occurred intraoperatively in a pediatric patient undergoing endoscopic fenestration and shunt revision. Accidental outflow occlusion of irrigation fluid and ventricular distension resulted in an acute increase in heart rate and arterial blood pressure. Subsequently, the patient developed stunned myocardium with global myocardial hypokinesia and pulmonary edema. She was promptly treated intraoperatively then admitted to the pediatric intensive care unit with resolution of her symptoms within 12 h. She was later discharged to home on the fourth postoperative day. In the current endoscopic era, this report highlights the possibility of intraoperative NSM and neurogenic pulmonary edema in the pediatric population. Early detection and treatment with a team approach help to achieve optimal control of this life-threatening condition and improve the outcome. PMID:26314948

  4. Liberal or restricted fluid administration: are we ready for a proposal of a restricted intraoperative approach?

    PubMed Central

    2014-01-01

    Background Fluid management in the perioperative period has been extensively studied but, despite that, “the right amount” still remains uncertain. The purpose of this paper is to summarize the state of the art of intraoperative fluid approach today. Discussion In the current medical literature there are only heterogeneous viewpoints that gives the idea of how confusing the situation is. The approach to the intraoperative fluid management is complex and it should be based on human physiology and the current evidence. Summary An intraoperative restrictive fluid approach in major surgery may be beneficial while Goal-directed Therapy should be superior to the liberal fluid strategy. Finally, we propose a rational approach currently used at our institution. PMID:25104915

  5. The Spitzer Warm Mission - Hot Science with a "Warm" Telescope

    NASA Astrophysics Data System (ADS)

    Soifer, Baruch T.; Carey, S.; Helou, G.; Hurt, R.; Rebull, L.; Squires, G. K.; Storrie-Lombardi, L.

    2007-12-01

    The Spitzer Space Telescope is the infrared component of NASA's family of Great Observatories comprised of the Chandra X-ray Observatory, the Compton Gamma Ray Observatory, and the Hubble Space Telescope. Cryogenically cooled and in Earth-trailing orbit, Spitzer currently offers imaging capabilities from 3.6-160 microns, and spectroscopy from 5-38 microns. In approximately March 2009, the liquid helium cryogen on-board Spitzer will be expended, but the observatory will remain operative with 3.6 and 4.5 micron imaging capabilities over two 5'x5' fields-of-view. Sensitivity in these channels will remain unchanged from the cryogenic mission. In this "warm" mission phase, Spitzer can operate until early 2014 with high-efficiency, providing up to 35,000 hours of science observing time. This enables several unprecedented opportunities to address fundamental and key scientific questions requiring large allocations of observing time, while maintaining opportunities for broad community use with more "traditional" time allocations, and funding for archival research. This presentation will review the technical and operational capabilities of Spitzer in the post-cryogen era, and will introduce some of the science enabled by warm Spitzer.

  6. Visual intraoperative estimation of cup and stem position is not reliable in minimally invasive hip arthroplasty.

    PubMed

    Woerner, Michael; Sendtner, Ernst; Springorum, Robert; Craiovan, Benjamin; Worlicek, Michael; Renkawitz, Tobias; Grifka, Joachim; Weber, Markus

    2016-06-01

    Background and purpose - In hip arthroplasty, acetabular inclination and anteversion-and also femoral stem torsion-are generally assessed by eye intraoperatively. We assessed whether visual estimation of cup and stem position is reliable. Patients and methods - In the course of a subgroup analysis of a prospective clinical trial, 65 patients underwent cementless hip arthroplasty using a minimally invasive anterolateral approach in lateral decubitus position. Altogether, 4 experienced surgeons assessed cup position intraoperatively according to the operative definition by Murray in the anterior pelvic plane and stem torsion in relation to the femoral condylar plane. Inclination, anteversion, and stem torsion were measured blind postoperatively on 3D-CT and compared to intraoperative results. Results - The mean difference between the 3D-CT results and intraoperative estimations by eye was -4.9° (-18 to 8.7) for inclination, 9.7° (-16 to 41) for anteversion, and -7.3° (-34 to 15) for stem torsion. We found an overestimation of > 5° for cup inclination in 32 hips, an overestimation of > 5° for stem torsion in 40 hips, and an underestimation < 5° for cup anteversion in 42 hips. The level of professional experience and patient characteristics had no clinically relevant effect on the accuracy of estimation by eye. Altogether, 46 stems were located outside the native norm of 10-20° as defined by Tönnis, measured on 3D-CT. Interpretation - Even an experienced surgeon's intraoperative estimation of cup and stem position by eye is not reliable compared to 3D-CT in minimally invasive THA. The use of mechanical insertion jigs, intraoperative fluoroscopy, or imageless navigation is recommended for correct implant insertion. PMID:26848628

  7. Intraoperative detection of radiolabeled compounds using a hand held gamma probe

    NASA Astrophysics Data System (ADS)

    Ricard, Marcel

    2001-02-01

    Scintillation cameras in Nuclear Medicine allow external detection of cancerous lesions after administration of a specific radiopharmaceutical to the patient. In some particular cases the affinity of the tracer is sufficient to consider the use of an intraoperative probe which enables the surgeon to identify radioactive tissues. A radiopharmaceutical consists of a radioisotope bound to a carrier molecule. The radioactive emissions must represent certain criteria in terms of half-life and energy to be detected during an operation. In the field of intraoperative detection radionuclides like 99mTc, 111In, 125I and 131I fall into this category. Their energy, which ranges from some 10 to 364 keV, cannot be properly detected by a single type of detector. Two technologies have been developed to yield detectors which are handy and sufficiently sensitive: semiconductor CdTe or CdZnTe to detect low energies and scintillator CsI(Tl) for higher energies. Today the intraoperative detection has been evaluated in the case of several pathologies such as osteoid osteoma, colorectal cancer, neuroblastoma, reoperation of differentiated thyroid carcinoma and localization of sentinel node in breast cancer and cutaneous melanoma. Obviously, the results obtained are not comparable from one indication to the other. Nevertheless, the surgeons have noted a considerable advantage in using the intraoperative probe in the case of neuroblastoma and thyroid surgery, especially when the reoperation is difficult or the localizations are ectopic or unusual. As regards the sentinel node, this concept represents a major new opportunity in the field of intraoperative detection and the results actually reported in the literature demonstrate that, when it is detected, elective node excision renders the staging of the disease more accurate. In conclusion, intraoperative detection supplies the surgeon with additional knowledge to be used in correlation with the patient's medical history.

  8. Chromogranin A and cortisol at intraoperative repeated noxious stimuli: Surgical stress in a dog model

    PubMed Central

    Hagman, Ragnvi; Stridsberg, Mats

    2015-01-01

    Objectives: Biomarkers representing sympathetic tone and the surgical stress response are measured to objectively evaluate surgical techniques and anaesthetic protocols. If a part of the intraoperative procedure is repeated on the contralateral organ, one animal may potentially serve as its own control and, if so, may minimize the problem of individual differences of the stress response to anaesthesia and surgery. This study aimed to investigate the use of chromogranin A for measurement of the intraoperative sympathetic tone. Additional aims were to investigate chromogranin A and cortisol as indicators of the intraoperative surgical stress response caused by repeated noxious stimuli in dogs subjected to ovariohysterectomy and thereby to investigate the possibility of one dog serving as its own control. Methods: Experiments were carried out on 10 dogs subjected to ovariohysterectomy. Perioperative blood samples (0–6) were collected after premedication, immediately before induction of anaesthesia (0), after induction of anaesthesia and before incision (1), before (2) and after (3) removal of the first ovary, after a 15-min pause before removal of the second ovary (4), after removal of the second ovary (5) and after closing the abdomen (6). Plasma chromogranin A and cortisol were analysed. Results: Plasma chromogranin A did not change. Plasma cortisol concentration did not change between before anaesthesia and opening of the abdomen. Plasma cortisol increased at removal of the first ovary. Cortisol did not change at removal of the second ovary but remained increased compared to initial sample. Conclusion: The results suggest chromogranin A is a poor indicator of intraoperative sympathetic tone during elective surgery in dogs. Cortisol measurement was useful for assessment of intraoperative noxious stimuli. However, at these test conditions, neither plasma chromogranin A nor plasma cortisol was useful for assessment of repeated intraoperative noxious stimuli where one dog served as its own control. PMID:26770773

  9. Safety, effectiveness and economic evaluation of intra-operative radiation therapy: a systematic review

    PubMed Central

    Najafipour, Farshad; Hamouzadeh, Pejman; Arabloo, Jalal; Mobinizadeh, Mohammadreza; Norouzi, Amir

    2015-01-01

    Background: Intra-operative radiation therapy (IORT) is the transfer of a single large radiation dose to the tumor bed during surgery with the final goal of improving regional tumor control. This study aimed to investigate the safety, effectiveness and economic evaluation of intra-operative radiation therapy. Methods: The scientific literature was searched in the main biomedical databases (Centre for Reviews and Dissemination, Cochrane Library and PubMed) up to March 2014. Two independent reviewers selected the papers based on pre-established inclusion criteria, with any disagreements being resolved by consensus. Data were then extracted and summarized in a structured form. Results from studies were analyzed and discussed within a descriptive synthesis. Results: Sixteen studies met the inclusion criteria. It seems that outcomes from using intraoperative radiation therapy can be considered in various kinds of cancers like breast, pancreatic and colorectal cancers. The application of this method may provide significant survival increase only for colorectal cancer, but this increase was not significant for other types of cancer. This technology had low complications; and it is relatively safe. Using intra-operative radiation therapy could potentially be accounted as a cost-effective strategy for controlling and managing breast cancer. Conclusion: According to the existing evidences, that are the highest medical evidences for using intra-operative radiation therapy, one can generally conclude that intra-operative radiation therapy is considered as a relatively safe and cost-effective method for managing early-stage breast cancer and it can significantly increase the survival of patients with colorectal cancer. Also, the results of this study have policy implications with respect to the reimbursement of this technology. PMID:26793649

  10. Warm/cold cloud processes

    NASA Technical Reports Server (NTRS)

    Bowdle, D. A.

    1979-01-01

    Technical assistance continued in support of the Atmospheric Cloud Physics Laboratory is discussed. A study of factors affecting warm cloud formation showed that the time of formation during an arbitrary expansion is independent of carrier gas composition for ideal gases and independent of aerosol concentration for low concentrations of very small aerosols. Equipment and procedures for gravimetric evaluation of a precision saturator were laboratory tested. A numerical feasibility study was conducted for the stable levitation of charged solution droplets by an electric field in a one-g static diffusion chamber. The concept, operating principles, applications, limits, and sensitivity of the levitation technique are discussed.

  11. Intraoperative imaging and fluorescence image guidance in oncologic surgery using a wearable fluorescence goggle system

    NASA Astrophysics Data System (ADS)

    Mondal, Suman B.; Gao, Shengkui; Zhu, Nan; Liu, Yang; Sudlow, Gail P.; Akers, Walter J.; Liang, Rongguang; Gruev, Viktor; Achilefu, Samuel

    2014-03-01

    We have developed a wearable, fluorescence goggle based system for intraoperative imaging of tumors and image guidance in oncologic surgery. Our system can detect fluorescence from cancer selective near infra-red (NIR) contrast agent, facilitating intraoperative visualization of surgical margins and tumors otherwise not apparent to the surgeon. The fluorescence information is displayed directly to the head mounted display (HMD) of the surgeon in real time, allowing unhindered surgical procedure under image guidance. This system has the potential of improving surgical outcomes in oncologic surgery and reduce the chances of cancer recurrence.

  12. Retrograde type A aortic dissection after thoracoabdominal aneurysm repair: early diagnosis with intraoperative transesophageal echocardiography.

    PubMed

    Rajan, Shobana; Sonny, Abraham; Sale, Shiva

    2015-03-01

    Retrograde type A aortic dissection that arises immediately after open replacement of the thoracoabdominal aorta is a rare and potentially lethal complication that has only been reported twice previously. A 74-year-old man with a history of expanding Crawford type I thoracoabdominal aortic aneurysm presented for open surgical repair. The intraoperative course was unremarkable. However, intraoperative transesophageal echocardiography after the repair revealed type A aortic dissection extending up to the sinotubular junction. Subsequently, emergent aortic arch repair was performed under deep hypothermic circulatory arrest. Early diagnosis with transesophageal echocardiography and optimal cerebral protection were instrumental in the successful outcome of this repair. PMID:25730411

  13. A cost comparison of allogeneic and preoperatively or intraoperatively donated autologous blood.

    PubMed

    Roberts, W A; Kirkley, S A; Newby, M

    1996-07-01

    We determined the cost of allogeneic packed red blood cells and autologous whole blood donated either preoperatively or in the operating room during hemodilution. Direct and indirect cost estimates were based on patients requiring simple transfusion and included procurement and preparation of the blood including testing performed, materials and time used, waste, and materials for administration. Data were derived from prospective blood bank time studies, material invoice records, and retrospective review of anesthesia times. Viral infection and transfusion reaction costs were accepted from previously published sources. Direct cost of purchasing and indirect costs of preparation resulted in an overall cost of $107.26 for the first unit of allogeneic packed red blood cells transfused. A second unit was slightly less costly ($100.89), as no type and screen was required and the same delivery set and filter can be used. The total cost of acquisition, processing, and transfusion of 1 U of preoperatively donated autologous blood was $97.83. The total cost of a 2-U transfusion of autologous whole blood donated in the operating room during acute normovolemic hemodilution was $83.10. These data suggest that autologous predonation of whole blood is somewhat less expensive than allogeneic packed red blood cells, and that hemodilution may be a cost effective alternative to autologous predonation in selected patients. PMID:8659723

  14. Primordial non-Gaussianity in noncanonical warm inflation

    NASA Astrophysics Data System (ADS)

    Zhang, Xiao-Min; Zhu, Jian-Yang

    2015-03-01

    We study the bispectrum of the primordial curvature perturbation on uniform density hypersurfaces generated by a kind of the noncanonical warm inflation, wherein the inflation is provided by a noncanonical scalar inflaton field that is coupled to radiation through a thermal dissipation effect. We obtain an analytic form for the nonlinear parameter fNL that describes the non-Gaussianity in first-order cosmological perturbation theory and analyze the magnitude of this nonlinear parameter. We make a comparison between our result and those of the standard inflation and the canonical warm inflation. We also discuss when the contribution to the non-Gaussianity due to the second-order perturbation theory becomes more important and what the observations predict. We take the Dirac-Born-Infeld inflation as a concrete example to find how the sound speed and the thermal dissipation strength to decide the non-Gaussianity and get a lower bound of the sound speed constrained by Planck.

  15. The importance of warm season warming to western U.S. streamflow changes

    NASA Astrophysics Data System (ADS)

    Das, Tapash; Pierce, David W.; Cayan, Daniel R.; Vano, Julie A.; Lettenmaier, Dennis P.

    2011-12-01

    Warm season climate warming will be a key driver of annual streamflow changes in four major river basins of the western U.S., as shown by hydrological model simulations using fixed precipitation and idealized seasonal temperature changes based on climate projections with SRES A2 forcing. Warm season (April-September) warming reduces streamflow throughout the year; streamflow declines both immediately and in the subsequent cool season. Cool season (October-March) warming, by contrast, increases streamflow immediately, partially compensating for streamflow reductions during the subsequent warm season. A uniform warm season warming of 3°C drives a wide range of annual flow declines across the basins: 13.3%, 7.2%, 1.8%, and 3.6% in the Colorado, Columbia, Northern and Southern Sierra basins, respectively. The same warming applied during the cool season gives annual declines of only 3.5%, 1.7%, 2.1%, and 3.1%, respectively.

  16. SOFIA Observations of S106: Dynamics of the Warm Gas

    NASA Technical Reports Server (NTRS)

    Simon, R.; Schneider, N.; Stutzki, J.; Gusten, R.; Graf, U. U.; Hartogh, P.; Guan, X.; Staguhn, J. G.; Benford, D. J.

    2012-01-01

    Context The H II region/PDR/molecular cloud complex S106 is excited by a single O-star. The full extent of the warm and dense gas close to the star has not been mapped in spectrally resolved high-J CO or [C II] lines, so the kinematics of the warm. partially ionized gas, are unknown. Whether the prominent dark lane bisecting the hourglass-shaped nebula is due solely to the shadow cast by a small disk around the exciting star or also to extinction in high column foreground gas was an open question until now. Aims. To disentangle the morphology and kinematics of warm neutral and ionized gas close to the star, study their relation to the bulk of the molecular gas. and to investigate the nature of the dark lane. Methods. We use the heterodyne receiver GREAT on board SOFIA to observe velocity resolved spectral lines of [C II] and CO 11 yields 10 in comparison with so far unpublished submm continuum data at 350 micron (8HARC-Il) and complementary molecular line data. Results. The high angular and spectral resolution observations show a very complex morphology and kinematics of the inner S106 region, with many different components at different excitation conditions contributing to the observed emission. The [C II] lines are found to be bright and very broad. tracing high velocity gas close to the interface of molecular cloud and H II region. CO 11 yields 10 emission is more confined.. both spatially and in velocity, to the immediate surroundings of S 106 IR showing the presence of warm, high density (clumpy) gas. Our high angular resolution submm continuum observations rule out the scenario where the dark lane separating the two lobes is due solely to the shadow cast by a small disk close to the star. The lane is clearly seen also as warm, high column density gas at the boundary of the molecular cloud and H II region.

  17. Warm gas TVC design study

    NASA Technical Reports Server (NTRS)

    Moorhead, S. B., Jr.

    1973-01-01

    A warm gas thrust vector control system was studied to optimize the injection geometry for a specific engine configuration, and an injection valve was designed capable of meeting the base line requirements. To optimize injection geometry, studies were made to determine the performance effects of varying injection location, angle, port size, and port configuration. Having minimized the injection flow rate required, a warm gas valve was designed to handle the required flow. A direct drive hydraulic servovalve capable of operating with highly contaminated hydraulic fluid was designed. The valve is sized to flow 15 gpm at 3000 psia and the direct drive feature is capable of applying a spool force of 200 pounds. The baseline requirements are the development of 6 deg of thrust vector control utilizing 2000 F (total temperature) gas for 180 seconds on a 1.37 million pound thrust engine burning LOX and RP-1 at a chamber pressure of 250 psia with a 155 inch long conical nozzle having a 68 inch diameter throat and a 153 inch diameter exit.

  18. Forecasting phenology under global warming

    PubMed Central

    Ibáñez, Inés; Primack, Richard B.; Miller-Rushing, Abraham J.; Ellwood, Elizabeth; Higuchi, Hiroyoshi; Lee, Sang Don; Kobori, Hiromi; Silander, John A.

    2010-01-01

    As a consequence of warming temperatures around the world, spring and autumn phenologies have been shifting, with corresponding changes in the length of the growing season. Our understanding of the spatial and interspecific variation of these changes, however, is limited. Not all species are responding similarly, and there is significant spatial variation in responses even within species. This spatial and interspecific variation complicates efforts to predict phenological responses to ongoing climate change, but must be incorporated in order to build reliable forecasts. Here, we use a long-term dataset (1953–2005) of plant phenological events in spring (flowering and leaf out) and autumn (leaf colouring and leaf fall) throughout Japan and South Korea to build forecasts that account for these sources of variability. Specifically, we used hierarchical models to incorporate the spatial variability in phenological responses to temperature to then forecast species' overall and site-specific responses to global warming. We found that for most species, spring phenology is advancing and autumn phenology is getting later, with the timing of events changing more quickly in autumn compared with the spring. Temporal trends and phenological responses to temperature in East Asia contrasted with results from comparable studies in Europe, where spring events are changing more rapidly than are autumn events. Our results emphasize the need to study multiple species at many sites to understand and forecast regional changes in phenology. PMID:20819816

  19. Trends in hemispheric warm and cold anomalies

    NASA Astrophysics Data System (ADS)

    Robeson, Scott M.; Willmott, Cort J.; Jones, Phil D.

    2014-12-01

    Using a spatial percentile approach, we explore the magnitude of temperature anomalies across the Northern and Southern Hemispheres. Linear trends in spatial percentile series are estimated for 1881-2013, the most recent 30 year period (1984-2013), and 1998-2013. All spatial percentiles in both hemispheres show increases from 1881 to 2013, but warming occurred unevenly via modification of cold anomalies, producing a reduction in spatial dispersion. In the most recent 30 year period, trends also were consistently positive, with warm anomalies having much larger warming rates than those of cold anomalies in both hemispheres. This recent trend has largely reversed the decrease in spatial dispersion that occurred during the twentieth century. While the period associated with the recent slowdown of global warming, 1998-2013, is too brief to estimate trends reliably, cooling was evident in NH warm and cold anomalies during January and February while other months in the NH continued to warm.

  20. Atlantic Warm Pool Trigger for the Younger Dryas Climate Event

    NASA Astrophysics Data System (ADS)

    Abdul, N. A.; Mortlock, R. A.; Wright, J. D.; Fairbanks, R. G.; Teneva, L. T.

    2011-12-01

    There is growing evidence that variability in the size and heat content of the tropical Atlantic Warm Pool impacts circum-North Atlantic climate via the Atlantic Multi-decadal Oscillation mode (Wang et al., 2008). The Atlantic Warm Pool spans the Gulf of Mexico, Caribbean Sea and the western tropical North Atlantic. Barbados is located near the center of the tropical Atlantic Warm Pool and coupled ocean models suggest that Barbados remains near the center of the tropical Atlantic Warm Pool under varying wind stress simulations. Measurements of the oxygen isotope paleothermometer in Acropora palmata coral species recovered from cores offshore Barbados, show a 3oC monotonic decrease in sea surface temperature from 13106 ± 83 to 12744 ± 61 years before present (errors given as 2 sigma). This interval corresponds to a sea level rise from 71.4 meters to 67.1 meters below present levels at Barbados. The 3oC temperature decrease is captured in eight A. palmata specimens that are in stratigraphic sequence, 230Th/234U dated, and analyzed for oxygen isotopes. All measurements are replicated. We are confident that this is the warm pool equivalent of the Younger Dryas climate event. The initiation of this temperature drop in the Atlantic Warm Pool predates the Younger Dryas start in Greenland ice cores, reported to start at 12896 ± 138 years (relative to AD 2000) (Rasmussen et al., 2006), while few other Younger Dryas climate records are dated with similar accuracy to make the comparison. Rasmussen, S.O., Andersen, K.K., Svensson, A.M., Steffensen, J.P., Vinther, B.M., Clausen, H.B., Siggaard-Andersen, M.L., Johnsen, S.J., Larsen, L.B., Dahl-Jensen, D., Bigler, M., Röthlisberger, R., Fischer, H., Goto-Azuma, K., Hansson, M.E., and Ruth, U., 2006, A new Greenland ice core chronology for the last glacial termination: J. Geophys. Res., v. 111, p. D06102. Wang, C., Lee, S.-K., and Enfield, D.B., 2008, Atlantic Warm Pool acting as a link between Atlantic Multidecadal Oscillation and Atlantic tropical cyclone activity: Geochem. Geophys. Geosyst., v. 9, p. Q05V03.

  1. Ecological stability in response to warming

    NASA Astrophysics Data System (ADS)

    Fussmann, Katarina E.; Schwarzmüller, Florian; Brose, Ulrich; Jousset, Alexandre; Rall, Björn C.

    2014-03-01

    That species’ biological rates including metabolism, growth and feeding scale with temperature is well established from warming experiments. The interactive influence of these changes on population dynamics, however, remains uncertain. As a result, uncertainty about ecological stability in response under warming remains correspondingly high. In previous studies, severe consumer extinction waves in warmed microcosms were explained in terms of warming-induced destabilization of population oscillations. Here, we show that warming stabilizes predator-prey dynamics at the risk of predator extinction. Our results are based on meta-analyses of a global database of temperature effects on metabolic and feeding rates and maximum population size that includes species of different phylogenetic groups and ecosystem types. To unravel population-level consequences we parameterized a bioenergetic predator-prey model and simulated warming effects within ecological, non-evolutionary timescales. In contrast to previous studies, we find that warming stabilized population oscillations up to a threshold temperature, which is true for most of the possible parameter combinations. Beyond the threshold level, warming caused predator extinction due to starvation. Predictions were tested in a microbial predator-prey system. Together, our results indicate a major change in how we expect climate change to alter natural ecosystems: warming should increase population stability while undermining species diversity.

  2. Essential training steps to achieving competency in the basic intraoperative transesophageal echocardiography examination for Chinese anesthesiologists.

    PubMed

    Peng, Yong G; Song, Haibo; Wang, E; Wang, Weipeng; Liu, Jin

    2015-03-01

    Guidelines for the intraoperative transesophageal echocardiography (TEE) examination have defined a detailed standard for medical professionals, particularly anesthesiologists, on how a TEE exam should proceed. Over the years, TEE has gained substantial popularity and emerged as a preferred monitoring modality to aid in perioperative management and decision making during hemodynamic instability situations or critical care settings. TEE training pathways and practice guidelines have been well established in western countries and many regions of the world. However, TEE training and practice information for anesthesiologists are lacking in China. As innovative technologies develop, other educational models have emerged to aid in obtaining competency in basic TEE exam. Hence, establishing a consensus on the ideal TEE training approach for anesthesiologists in China is urgently needed. Developing an effective curriculum that can be incorporated into an anesthesiology resident's overall training is also necessary to provide knowledge and skills toward competency in basic TEE exam. With evolving medical system reforms and increasing demands for intraoperative hemodynamic monitoring to accommodate surgical innovations, anesthesiology professionals are increasingly obliged to perform intraoperative TEE exams in their current and future practices. To overcome obstacles and achieve significant progress in using the TEE modality to help in intraoperative management and surgical decision making, publishing basic TEE training guidelines for China's anesthesiologists is an important endeavor. PMID:25337689

  3. Initial experience of using high field strength intraoperative MRI for neurosurgical procedures.

    PubMed

    Raheja, Amol; Tandon, Vivek; Suri, Ashish; Sarat Chandra, P; Kale, Shashank S; Garg, Ajay; Pandey, Ravindra M; Kalaivani, Mani; Mahapatra, Ashok K; Sharma, Bhawani S

    2015-08-01

    We report our initial experience to optimize neurosurgical procedures using high field strength intraoperative magnetic resonance imaging (IOMRI) in 300 consecutive patients as high field strength IOMRI rapidly becomes the standard of care for neurosurgical procedures. Three sequential groups (groups A, B, C; n=100 each) were compared with respect to time management, complications and technical difficulties to assess improvement in these parameters with experience. We observed a reduction in the number of technical difficulties (p<0.001), time to induction (p<0.001) and total anesthesia time (p=0.007) in sequential groups. IOMRI was performed for neuronavigation guidance (n=252) and intraoperative validation of extent of resection (EOR; n=67). Performing IOMRI increased the EOR over and beyond the primary surgical attempt in 20.5% (29/141) and 18% (11/61) of patients undergoing glioma and pituitary surgery, respectively. Overall, EOR improved in 59.7% of patients undergoing IOMRI (40/67). Intraoperative tractography and real time navigation using re-uploaded IOMRI images (accounting for brain shift) helps in intraoperative planning to reduce complications. IOMRI is an asset to neurosurgeons, helping to augment the EOR, especially in glioma and pituitary surgery, with no significant increase in morbidity to the patient. PMID:26077939

  4. Automatic pre- to intra-operative CT registration for image-guided cochlear implant surgery

    PubMed Central

    Reda, Fitsum A.; Noble, Jack H.; Labadie, Robert F.; Dawant, Benoit M.

    2015-01-01

    Percutaneous cochlear implantation (PCI) is a minimally invasive image-guided cochlear implant approach, where access to the cochlea is achieved by drilling a linear channel from the skull surface to the cochlea. The PCI approach requires pre- and intra-operative planning. Computation of a safe linear drilling trajectory is performed in a pre-operative CT. This trajectory is mapped to intra-operative space using the transformation matrix that registers the pre- and intra-operative CTs. However, the difference in orientation between the pre- and intra-operative CTs is too extreme to be recovered by standard, gradient descent based registration methods. Thus far, the registration has been initialized manually by an expert. In this work we present a method that aligns the scans completely automatically. We compared the performance of the automatic approach to the registration approach when an expert does the manual initialization on 11 pairs of scans. There is a maximum difference of 0.18 mm between the entry and target points of the trajectory mapped with expert initialization and the automatic registration method. This suggests that the automatic registration method is accurate enough to be used in a PCI surgery. PMID:22922692

  5. Anesthesia during high-field intraoperative magnetic resonance imaging experience with 80 consecutive cases.

    PubMed

    Schmitz, Bernd; Nimsky, Christopher; Wendel, Georg; Wienerl, Juergen; Ganslandt, Oliver; Jacobi, Klaus; Fahlbusch, Rudolf; Schüttler, Juergen

    2003-07-01

    Intraoperative magnetic resonance imaging (MRI) has been used for years to update neuronavigation and for intraoperative resection control. For this purpose, low-field (0.1-0.2 T) MR scanners have been installed in the operating room, which, in contrast to machines using higher magnetic field strength, allowed the use of standard anesthetic and surgical equipment. However, these low-field MR systems provided only minor image quality and a limited battery of MR sequences, excluding functional MRI, diffusion-weighted MRI, or MR angiography and spectroscopy. Based on these advantages, a concept using high-field MRI (1.5 T) with intraoperative functional neuronavigational guidance has been developed that required adaptation of the anesthetic regimen to working in the close vicinity to the strong magnetic field. In this paper the authors present their experience with the first 80 consecutive patients who received anesthesia in a specially designed radio frequency-shielded operating room equipped with a high-field (1.5 T) MR scanner. We describe the MR-compatible anesthesia equipment used including ventilator, monitoring, and syringe pumps, which allow standard neuroanesthesia in this new and challenging environment. This equipment provides the use of total intravenous anesthesia with propofol and remifentanil allowing rapid extubation and neurologic examination following surgery. In addition, extended intraoperative monitoring including EEG monitoring required for intracranial surgery is possible. Moreover, problems and dangers related to the effects of the strong magnetic field are discussed. PMID:12826974

  6. Clinical toxicity of peripheral nerve to intraoperative radiotherapy in a canine model

    SciTech Connect

    Johnstone, P.A.S.; DeLuca, A.M.; Terrill, R.E.

    1995-07-15

    The clinical late effects of intraoperative radiotherapy (IORT) on peripheral nerve were investigated in a foxhound model. Between 1982 and 1987, 40 animals underwent laparotomy with intraoperative radiotherapy of doses from 0-75 Gy administered to the right lumbosacral plexus. Subsequently, all animals were monitored closely and sacrificed to assess clinical effects to peripheral nerve. This analysis reports final clinical results of all animals, with follow-up to 5 years. All animals treated with {>=} 25 Gy developed ipsilateral neuropathy. An inverse relationship was noted between intraoperative radiotherapy dose and time to neuropathy, with an effective dose for 50% paralysis (ED{sub 50}) of 17.2 Gy. One of the animals treated with 15 Gy IORT developed paralysis, after a much longer latency than the other animals. Doses of 15 Gy delivered intraoperatively may be accompanied by peripheral neuropathy with long-term follow-up. This threshold is less than that reported with shorter follow-up. The value of ED{sub 50} determined here is in keeping with data from other animal trials, and from clinical trials in humans. 11 refs., 2 figs.

  7. Parathyroid Carcinoma: Current Understanding and New Insights into Gene Expression and Intraoperative Parathyroid Hormone Kinetics

    PubMed Central

    Abdelgadir Adam, Mohamed; Untch, Brian R.

    2010-01-01

    Parathyroid carcinoma is an indolent but ultimately life-threatening malignancy. Due to the lack of definitive diagnostic markers and overlapping clinical features of benign primary hyperparathyroidism (PHPT), this disease is often misdiagnosed as parathyroid adenoma. Therefore, a high index of suspicion preoperatively and early intraoperative recognition with en bloc surgical resection are crucial for favorable outcome. Owing to the rarity of the disease, little is known about the molecular pathogenesis of parathyroid carcinoma. Here, we review the literature to present current understanding of the disease and provide new information on gene expression and use of intraoperative parathyroid hormone (PTH) monitoring in the surgical management of this rare malignancy. Specifically, using microarray transcriptome analysis of an unequivocal case of parathyroid carcinoma and a biopsy from the same patient's normal parathyroid gland, we identify APP, CDH1, KCNJ16, and UCHL1 as differentially expressed genes in parathyroid carcinoma. Further, using case records from four cases of unequivocal parathyroid carcinoma, we compared intraoperative PTH kinetics of these patients to 475 patients with benign PHPT, and show that intraoperative PTH monitoring is accurate in predicting postoperative normocalcemia in initial en bloc operations for parathyroid carcinoma. PMID:20051478

  8. Impact of Intraoperative Acetaminophen Administration on Postoperative Opioid Consumption in Patients Undergoing Hip or Knee Replacement

    PubMed Central

    Vaughan, Cathy; McGee, Ann

    2014-01-01

    Abstract Background: Opioid utilization for acute pain has been associated with numerous adverse events, potentially resulting in longer inpatient stays and increased costs. Objective: To examine the effect of intravenous (IV) acetaminophen administered intraoperatively on postoperative opioid consumption in adult subjects who underwent hip or knee replacement. Methods: This retrospective cohort study evaluated postoperative opioid consumption in 176 randomly selected adult subjects who underwent hip or knee replacement at Duke University Hospital (DUH). Eighty-eight subjects received a single, intraoperative, 1 g dose of IV acetaminophen. The other subjects did not receive any IV acetaminophen. This study evaluated mean opioid consumption (in oral morphine equivalents) during the 24-hour postoperative period in the 2 groups. Other endpoints included length of stay in the postanesthesia care unit (PACU), incidence of oversedation, need for acute opioid reversal, and adjunctive analgesic utilization. Results: Subjects who were given a single dose of intraoperative acetaminophen received an average of 149.3 mg of oral morphine equivalents during the 24 hours following surgery compared to 147.2 mg in participants who were not exposed to IV acetaminophen (P = .904). The difference in average length of PACU stay between the IV acetaminophen group (163 minutes) and those subjects not exposed to IV acetaminophen (169 minutes) was not statistically significant (P = .588). No subjects in the study experienced oversedation or required acute opioid reversal. Conclusion: There was not a statistically significant difference in postoperative opioid consumption between patients receiving and not receiving IV acetaminophen intraoperatively. PMID:25673891

  9. Automatic pre- to intra-operative CT registration for image-guided cochlear implant surgery

    NASA Astrophysics Data System (ADS)

    Reda, Fitsum A.; Dawant, Benoit M.; Labadie, Robert F.; Noble, Jack H.

    2012-02-01

    Percutaneous cochlear implantation (PCI) is a minimally invasive image-guided cochlear implant approach, where access to the cochlea is achieved by drilling a linear channel from the outer skull to the cochlea. The PCI approach requires pre- and intra-operative planning. Segmentation of critical ear anatomy and computation of a safe drilling trajectory are performed in a pre-operative CT. The computed safe drilling trajectory must then be mapped to the intraoperative space. The mapping can be done using the transformation matrix that registers the pre- and intra-operative CTs. However, the difference in orientation between the pre- and intra-operative CTs is too extreme to be recovered by standard, gradient descent-based registration methods. Thus, we have so far relied on an expert to manually initialize the registration. In this work we present a method that aligns the scans automatically. We compared the performance of the automatic approach to the registration approach when an expert does the manual initialization on ten pairs of scans. There is a maximum difference of 0.19 mm between the entry and target points resulting from the automatic and manually initialized registration processes. This suggests that the automatic registration method is accurate enough to be used in a PCI surgery.

  10. Dissociation of Subtraction and Multiplication in the Right Parietal Cortex: Evidence from Intraoperative Cortical Electrostimulation

    ERIC Educational Resources Information Center

    Yu, Xiaodan; Chen, Chuansheng; Pu, Song; Wu, Chenxing; Li, Yongnian; Jiang, Tao; Zhou, Xinlin

    2011-01-01

    Previous research has consistently shown that the left parietal cortex is critical for numerical processing, but the role of the right parietal lobe has been much less clear. This study used the intraoperative cortical electrical stimulation approach to investigate neural dissociation in the right parietal cortex for subtraction and…

  11. Three intraoperative methods to determine limb-length discrepancy in THA.

    PubMed

    Rice, Ian S; Stowell, R Lee; Viswanath, Purab C; Cortina, Gary J

    2014-05-01

    Limb-length discrepancy (LLD) is a common concern for both surgeon and patient in the setting of elective total hip arthroplasty (THA). There is a paucity of evidence guiding surgeons to an optimal method for measuring intraoperative LLD and minimizing postoperative LLD. The primary objective of this prospective, randomized, double-blinded study was to determine which of 3 intraoperative methods used at the authors' institution was best correlated to postoperative radiographic LLD. From 2011 to 2012, 81 patients undergoing either primary (75) or revision (6) THA with an anterolateral (Watson-Jones) approach were prospectively randomized and received intraoperative measurement of LLD via 1 of 3 methods: abductor shuck (AS), tranosseous pins with calibrated caliper (TP), or patella electrocardiogram (EKG) leads (PL). Intraoperative measurements of LLD were compared to clinical and radiographic postoperative measurements of LLD, and absolute differences and correlation coefficients were calculated for each method. Overall, the mean LLD preoperatively was 8.09 mm, and mean radiographic LLD postoperatively was 4.20 mm. The AS method was associated with the highest correlation to postoperative radiographic LLD (R=0.360; P<.05), whereas the other methods had mildly positive but statistically insignificant correlations (TP R=0.275; P>.05; PL R=0.301; P>.05). The AS method best correlates to postoperative radiographic LLD among the 3 techniques, although all methods were positively correlated. Clinical measurements of LLD correlate poorly with radiographic measurements and may be of limited utility. PMID:24810827

  12. Numerical characterization of intraoperative and chronic electrodes in deep brain stimulation

    PubMed Central

    Paffi, Alessandra; Camera, Francesca; Apollonio, Francesca; d’Inzeo, Guglielmo; Liberti, Micaela

    2015-01-01

    An intraoperative electrode (microelectrode) is used in the deep brain stimulation (DBS) technique to pinpoint the brain target and to choose the best parameters for the electrical stimulus. However, when the intraoperative electrode is replaced with the chronic one (macroelectrode), the observed effects do not always coincide with predictions. To investigate the causes of such discrepancies, a 3D model of the basal ganglia has been considered and realistic models of both intraoperative and chronic electrodes have been developed and numerically solved. Results of simulations of the electric potential (V) and the activating function (AF) along neuronal fibers show that the different geometries and sizes of the two electrodes do not change the distributions and polarities of these functions, but rather the amplitudes. This effect is similar to the one produced by the presence of different tissue layers (edema or glial tissue) in the peri-electrode space. Conversely, an inaccurate positioning of the chronic electrode with respect to the intraoperative one (electric centers not coincident) may induce a completely different electric stimulation in some groups of fibers. PMID:25745397

  13. Comparing the dosimetric characteristics of the electron beam from dedicated intraoperative and conventional radiotherapy accelerators.

    PubMed

    Baghani, Hamid Reza; Aghamiri, Seyed Mahmoud Reza; Mahdavi, Seyed Rabi; Akbari, Mohammad Esmail; Mirzaei, Hamid Reza

    2015-01-01

    The specific design of the mobile dedicated intraoperative radiotherapy (IORT) accelerators and different electron beam collimation system can change the dosimetric characteristics of electron beam with respect to the conventional accelerators. The aim of this study is to measure and compare the dosimetric characteristics of electron beam produced by intraoperative and conventional radiotherapy accelerators. To this end, percentage depth dose along clinical axis (PDD), transverse dose profile (TDP), and output factor of LIAC IORT and Varian 2100C/D conventional radiotherapy accelerators were measured and compared. TDPs were recorded at depth of maximum dose. The results of this work showed that depths of maximum dose, R90, R50, and RP for LIAC beam are lower than those of Varian beam. Furthermore, for all energies, surface doses related to the LIAC beam are substantially higher than those of Varian beam. The symmetry and flatness of LIAC beam profiles are more desirable compared to the Varian ones. Contrary to Varian accelerator, output factor of LIAC beam substantially increases with a decrease in the size of the applicator. Dosimetric characteristics of beveled IORT applicators along clinical axis were different from those of the flat ones. From these results, it can be concluded that dosimetric characteristics of intraoperative electron beam are substantially different from those of conventional clinical electron beam. The dosimetric characteristics of the LIAC electron beam make it a useful tool for intraoperative radiotherapy purposes. PMID:26103175

  14. Robotic-assisted laparoscopic wedge resection of a gastric leiomyoma with intraoperative ultrasound localization.

    PubMed

    Abdel Khalek, Mohamed; Joshi, Virendra; Kandil, Emad

    2011-12-01

    Gastric leiomyoma is a rare gastric neoplasm that traditionally has been resected for negative margins using an open approach. The laparoscopic approach may also treat various gastric tumors without opening the gastric cavity. Robotic surgery was developed in response to the limitations and drawbacks of laparoscopic surgery. Herein, we describe a case of robotic-assisted laparoscopic wedge resection of a gastric leiomyoma. A 63-year-old male complaining of abdominal pain was found to have an incidental 3 cm antral mass on an abdominal CT. Endoscopy with endoscopic ultrasound (EUS) confirmed a submucosal mass. Biopsy of the lesion was consistent with a leiomyoma. The DaVinci robotic system was used for partial gastrectomy and reconstruction, with the addition of intraoperative ultrasound to localize the lesion intraoperatively. Pathological examination of the resected mass confirmed a diagnosis of leiomyoma with negative margins. There were no intraoperative or postoperative complications. The patient was discharged home on the second postoperative day. Intraoperative endoscopic ultrasound is a safe technique that may improve the success rate of surgery by confirming the location of the lesion. Robotic assistance in gastric resection offers an easy minimally invasive approach to such tumors. This approach can achieve adequate surgical margins and lead to short hospital stays. PMID:21919811

  15. 3D monitoring of the intraoperative brainshift by means of photogrammetry

    NASA Astrophysics Data System (ADS)

    D'Apuzzo, Nicola; Verius, Michael

    2008-02-01

    This paper presents the preliminary results of applying multi image photogrammetric techniques for the three-dimensional monitoring of the intraoperative brainshift. The "brainshift" is the motion of cerebral structures occurring in neurosurgery after the craniotomy (opening of the skull in order to access the brain for surgical repair). The causes of this effect are mainly the changes of pressure and loss of cerebrospinal liquid. The phenomenon of brainshift can influence negatively the planning and execution of neurosurgical intervention. A research project at the Clinic of Neuroradiology and Neurosurgery of the Medical University of Innsbruck, Austria) aims at the quantification of the intraoperative brainshift by means of photogrammetry. The goals of the project are: (i) the development of a multi-image photogrammetric system for the quantitative monitoring of intraoperative brainshift by means of 3D measurements performed on the surface of the brain during neurosurgery after craniotomy, (ii) transformation of the pre-operative performed MR and CT datasets in function of the quantified intra-operative brainshift. This paper presents the proposed multi-image photogrammetric system, as well as, the first results achieved, in collaboration with Hometrica Consulting, for the automatic 3D measurement and tracking of selected points on the surface of the brain.

  16. Persistent and automatic intraoperative 3D digitization of surfaces under dynamic magnifications of an operating microscope

    PubMed Central

    Kumar, Ankur N.; Miga, Michael I.; Pheiffer, Thomas S.; Chambless, Lola B.; Thompson, Reid C.; Dawant, Benoit M.

    2014-01-01

    One of the major challenges impeding advancement in image-guided surgical (IGS) systems is the soft-tissue deformation during surgical procedures. These deformations reduce the utility of the patient’s preoperative images and may produce inaccuracies in the application of preoperative surgical plans. Solutions to compensate for the tissue deformations include the acquisition of intraoperative tomographic images of the whole organ for direct displacement measurement and techniques that combines intraoperative organ surface measurements with computational biomechanical models to predict subsurface displacements. The later solution has the advantage of being less expensive and amenable to surgical workflow. Several modalities such as textured laser scanners, conoscopic holography, and stereo-pair cameras have been proposed for the intraoperative 3D estimation of organ surfaces to drive patient-specific biomechanical models for the intraoperative update of preoperative images. Though each modality has its respective advantages and disadvantages, stereo-pair camera approaches used within a standard operating microscope is the focus of this article. A new method that permits the automatic and near real-time estimation of 3D surfaces (at 1Hz) under varying magnifications of the operating microscope is proposed. This method has been evaluated on a CAD phantom object and on full-length neurosurgery video sequences (~1 hour) acquired intraoperatively by the proposed stereovision system. To the best of our knowledge, this type of validation study on full-length brain tumor surgery videos has not been done before. The method for estimating the unknown magnification factor of the operating microscope achieves accuracy within 0.02 of the theoretical value on a CAD phantom and within 0.06 on 4 clinical videos of the entire brain tumor surgery. When compared to a laser range scanner, the proposed method for reconstructing 3D surfaces intraoperatively achieves root mean square errors (surface-to-surface distance) in the 0.28-0.81mm range on the phantom object and in the 0.54-1.35mm range on 4 clinical cases. The digitization accuracy of the presented stereovision methods indicate that the operating microscope can be used to deliver the persistent intraoperative input required by computational biomechanical models to update the patient’s preoperative images and facilitate active surgical guidance. PMID:25189364

  17. Persistent and automatic intraoperative 3D digitization of surfaces under dynamic magnifications of an operating microscope.

    PubMed

    Kumar, Ankur N; Miga, Michael I; Pheiffer, Thomas S; Chambless, Lola B; Thompson, Reid C; Dawant, Benoit M

    2015-01-01

    One of the major challenges impeding advancement in image-guided surgical (IGS) systems is the soft-tissue deformation during surgical procedures. These deformations reduce the utility of the patient's preoperative images and may produce inaccuracies in the application of preoperative surgical plans. Solutions to compensate for the tissue deformations include the acquisition of intraoperative tomographic images of the whole organ for direct displacement measurement and techniques that combines intraoperative organ surface measurements with computational biomechanical models to predict subsurface displacements. The later solution has the advantage of being less expensive and amenable to surgical workflow. Several modalities such as textured laser scanners, conoscopic holography, and stereo-pair cameras have been proposed for the intraoperative 3D estimation of organ surfaces to drive patient-specific biomechanical models for the intraoperative update of preoperative images. Though each modality has its respective advantages and disadvantages, stereo-pair camera approaches used within a standard operating microscope is the focus of this article. A new method that permits the automatic and near real-time estimation of 3D surfaces (at 1 Hz) under varying magnifications of the operating microscope is proposed. This method has been evaluated on a CAD phantom object and on full-length neurosurgery video sequences (∼1 h) acquired intraoperatively by the proposed stereovision system. To the best of our knowledge, this type of validation study on full-length brain tumor surgery videos has not been done before. The method for estimating the unknown magnification factor of the operating microscope achieves accuracy within 0.02 of the theoretical value on a CAD phantom and within 0.06 on 4 clinical videos of the entire brain tumor surgery. When compared to a laser range scanner, the proposed method for reconstructing 3D surfaces intraoperatively achieves root mean square errors (surface-to-surface distance) in the 0.28-0.81 mm range on the phantom object and in the 0.54-1.35 mm range on 4 clinical cases. The digitization accuracy of the presented stereovision methods indicate that the operating microscope can be used to deliver the persistent intraoperative input required by computational biomechanical models to update the patient's preoperative images and facilitate active surgical guidance. PMID:25189364

  18. Local cooling despite global warming

    NASA Astrophysics Data System (ADS)

    Girihagama, Lakshika Nilmini Kumari

    How much warmer is the ocean surface than the atmosphere directly above it? Part 1 of the present study offers a means to quantify this temperature difference using a nonlinear one-dimensional global energy balance coupled ocean--atmosphere model ("Aqua Planet"). The significance of our model, which is of intermediate complexity, is its ability to obtain an analytical solution for the global average temperatures. Preliminary results show that, for the present climate, global mean ocean temperature is 291.1 K whereas surface atmospheric temperature is 287.4 K. Thus, the surface ocean is 3.7 K warmer than the atmosphere above it. Temporal perturbation of the global mean solution obtained for "Aqua Planet" showed a stable system. Oscillation amplitude of the atmospheric temperature anomaly is greater in magnitude to those found in the ocean. There is a phase shift (a lag in the ocean), which is caused by oceanic thermal inertia. Climate feedbacks due to selected climate parameters such as incoming radiation, cloud cover, and CO2 are discussed. Warming obtained with our model compares with Intergovernmental Panel on Climate Change's (IPCC) estimations. Application of our model to local regions illuminates the importance of evaporative cooling in determining derived air-sea temperature offsets, where an increase in the latter increases the systems overall sensitivity to evaporative cooling. In part 2, we wish to answer the fairly complicated question of whether global warming and an increased freshwater flux cause Northern Hemispheric warming or cooling. Starting from the assumption of the ocean as the primary source of variability in the Northern hemispheric ocean--atmosphere coupled system, we employed a simple non--linear one--dimensional coupled ocean--atmosphere model similar to the "Aqua Planet" model but with additional advective heat transports. The simplicity of this model allows us to analytically predict the evolution of many dynamical variables of interest such as, the strength of the Atlantic Meridional overturning circulation (AMOC), temperatures of the ocean and atmosphere, mass transports, salinity, and ocean--atmosphere heat fluxes. Model results show that a reduced AMOC transport due to an increased freshwater flux causes cooling in both the atmosphere and ocean in the North Atlantic (NA) deep--water formation region. Cooling in both the ocean and atmosphere can cause a reduction of the ocean--atmosphere temperature difference, which in turn reduces heat fluxes in both the ocean and atmosphere. For present day climate parameters, the calculated critical freshwater flux needed to arrest AMOC is 0.14 Sv. Assuming a constant atmospheric zonal flow, there is both minimal reduction in the AMOC strength, as well as minimal warming of the ocean and atmosphere. This model provides a conceptual framework for a dynamically sound response of the ocean and atmosphere to AMOC variability as a function of increased freshwater flux. The results are qualitatively consistent with numerous realistic coupled numerical models of varying complexity.

  19. Sudden stratospheric warmings as catastrophes

    NASA Technical Reports Server (NTRS)

    Chao, W. C.

    1985-01-01

    The sudden stratospheric warming (SSW) process is qualitatively studied using a conceptual and numerical approach guided by catastrophe theory. A simple example of a catastrophe taken from nonlinear dynamics is given, and results from previous modelling studies of SSW are interpreted in light of catastrophe theory. Properties of this theory such as hysteresis, cusp, and triggering essential to SSW are numerically demonstrated using the truncated quasi-geostrophic beta-plane model of Holton and Mass (1976). A qualitative explanation of the transition from the steady regime to the vacillation regime is given for the Holton and Mass model in terms of the topographically induced barotropic Rossby wave instability. Some implications for the simulation and prediction of SSW are discussed.

  20. DPIS for warm dense matter

    SciTech Connect

    Kondo, K.; Kanesue, T.; Horioka, K.; Okamura, M.

    2010-05-23

    Warm Dense Matter (WDM) offers an challenging problem because WDM, which is beyond ideal plasma, is in a low temperature and high density state with partially degenerate electrons and coupled ions. WDM is a common state of matter in astrophysical objects such as cores of giant planets and white dwarfs. The WDM studies require large energy deposition into a small target volume in a shorter time than the hydrodynamical time and need uniformity across the full thickness of the target. Since moderate energy ion beams ({approx} 0.3 MeV/u) can be useful tool for WDM physics, we propose WDM generation using Direct Plasma Injection Scheme (DPIS). In the DPIS, laser ion source is connected to the Radio Frequency Quadrupole (RFQ) linear accelerator directly without the beam transport line. DPIS with a realistic final focus and a linear accelerator can produce WDM.

  1. Meteorology: hurricanes and global warming.

    PubMed

    Landsea, Christopher W

    2005-12-22

    Anthropogenic climate change has the potential for slightly increasing the intensity of tropical cyclones through warming of sea surface temperatures. Emanuel has shown a striking and surprising association between sea surface temperatures and destructiveness by tropical cyclones in the Atlantic and western North Pacific basins. However, I question his analysis on the following grounds: it does not properly represent the observations described; the use of his Atlantic bias-removal scheme may not be warranted; and further investigation of a substantially longer time series for tropical cyclones affecting the continental United States does not show a tendency for increasing destructiveness. These factors indicate that instead of "unprecedented" tropical cyclone activity having occurred in recent years, hurricane intensity was equal or even greater during the last active period in the mid-twentieth century. PMID:16371953

  2. Liquid Cooling/Warming Garment

    NASA Technical Reports Server (NTRS)

    Koscheyev, Victor S.; Leon, Gloria R.; Dancisak, Michael J.

    2010-01-01

    The NASA liquid cooling/ventilating garment (LCVG) currently in use was developed over 40 years ago. With the commencement of a greater number of extra-vehicular activity (EVA) procedures with the construction of the International Space Station, problems of astronaut comfort, as well as the reduction of the consumption of energy, became more salient. A shortened liquid cooling/warming garment (SLCWG) has been developed based on physiological principles comparing the efficacy of heat transfer of different body zones; the capability of blood to deliver heat; individual muscle and fat body composition as a basis for individual thermal profiles to customize the zonal sections of the garment; and the development of shunts to minimize or redirect the cooling/warming loop for different environmental conditions, physical activity levels, and emergency situations. The SLCWG has been designed and completed, based on extensive testing in rest, exercise, and antiorthostatic conditions. It is more energy efficient than the LCVG currently used by NASA. The total length of tubing in the SLCWG is approximately 35 percent less and the weight decreased by 20 percent compared to the LCVG. The novel features of the innovation are: 1. The efficiency of the SLCWG to maintain thermal status under extreme changes in body surface temperatures while using significantly less tubing than the LCVG. 2. The construction of the garment based on physiological principles of heat transfer. 3. The identification of the body areas that are most efficient in heat transfer. 4. The inclusion of a hood as part of the garment. 5. The lesser consumption of energy.

  3. Warm-season soil moisture-temperature coupling in historical and future climate projections

    NASA Astrophysics Data System (ADS)

    Williams, I. N.

    2014-12-01

    Anomalously dry soil moisture can lead to reduced evapotranspiration and increased surface temperatures. These higher temperatures have been hypothesized to further reduce soil moisture, enhance temperature variability, and prolong dry extremes, particularly in warmer climates. Historical and future climate projections from the Coupled Model Inter-comparison Project (CMIP5) were investigated in this study to identify climate trends attributable to soil moisture-temperature coupling and feedback processes. It was found that the probability of temperature extremes (departures from seasonal averages) increases under global warming, and the time taken to return toward average warm-season temperatures following temperature extremes (i.e. persistence) increases by more than 25% over many land regions. An analysis of changes in surface energy balance suggests that this increased persistence of warm temperature extremes results from decreased surface longwave radiative cooling at warm temperature extremes under global warming. This process was also found in radiative forcing experiments using a single-column climate model having a realistic radiation scheme and a simplified land surface model, where the sensitivity of extremes to the relationship between soil moisture and transpiration was further investigated. The persistence of warm extremes depends on the soil moisture content at stomatal closure (wilting point), where higher wilting points lead to larger reductions in surface longwave emission at warm extremes and increased persistence of extremes. These results highlight the importance of surface radiation regime and vegetation in soil moisture-temperature feedbacks.

  4. Significance of intraoperative testing in right-sided implantable cardioverter-defibrillators

    PubMed Central

    2013-01-01

    Background Implantation of implantable cardioverter-defibrillators (ICD) from the left pectoral region is the standard therapeutical method. Increasing numbers of system revisions due to lead dysfunction and infections will consecutively increase the numbers of right-sided implantations. The reliability of devices implanted on the right pectoral side remains controversially discussed, and the question of testing these devices remains unanswered. Methods In a prospectively designed study all 870 patients (60.0±14 years, 689 male) who were treated with a first ICD from July 2005 until May 2012 and tested intraoperatively according to the testing protocol were analyzed. The indication for implantation was primary prophylactic in 71.5%. Underlying diseases included ischemic cardiomyopathy (50%), dilative cardiomyopathy (37%), and others (13%). Mean ejection faction was 27±12%. Implantation site was right in 4.5% and left in 95.5%. Results Five patients supplied with right-sided ICD (13%, p = 0.02 as compared to left-sided) failed initial intraoperative testing with 21 J. 3 patients were male. The age of the patients failing intraoperative testing with right-sided devices appeared higher than of patients with left-sided devices (p = 0.07). The ejection fraction was 28±8%. All patients reached a sufficient DFT ≤ 21 J after corrective procedures. Conclusion Implantation of ICDs on the right side results in significantly higher failure rate of successful termination of intraoperatively induced ventricular fibrillation. The data of our study suggest the necessity of intraoperative ICD testing in right-sided implanted ICDs. PMID:23577747

  5. Intraoperative computed tomography with the mobile CT Tomoscan M during surgical treatment of orbital fractures.

    PubMed

    Hoelzle, F; Klein, M; Schwerdtner, O; Lueth, T; Albrecht, J; Hosten, N; Felix, R; Bier, J

    2001-02-01

    Up to now it has only been possible to monitor the alignment of orbital floor fractures postoperatively with a computed tomography (CT) examination with coronal sectioning. If this showed an incorrect positioning, renewed surgery and anaesthetics were often required. The purpose of this study was the implementation and definition of the spectrum of indications for intraoperative CT examinations while keeping patient radiation exposure to a minimum. Thirty-two orbital fracture cases were examined pre- and intraoperatively using the mobile computer tomograph Tomoscan M in coronal sectioning. In this patient collective, 12 cases showed an isolated orbital floor fracture and twenty cases an orbital floor fracture associated with a zygomatic fracture. The technical prerequisite for these examinations was the construction of a suitable radiolucent operating table which permitted coronal sections to be made with the CT-Gantry tilted. The authors aimed to reduce radiation exposure by optimizing the technical setting parameters and closely defining the scan region for the operator. In three of 32 cases there were no surgical indications following clinical and preoperative CT examination. In three of the 20 cases with associated zygomatic fracture a closed reduction with a reduction hook was carried out, and no revision was necessary after the intraoperative CT examination. In 26 cases an open reduction was carried out. Of these open reduced fractures, four had to be revised after intraoperative CT monitoring; one of the isolated orbital floor fractures and three of those associated with a zygomatic fracture. Intraoperative CT monitoring of orbital floor fractures is considered a useful surgical aid. Its advantages are immediate monitoring of the surgical reduction, the presence of the surgeon during scanning enabling him to determine directly the relevant sections to scan, and the resulting radiation exposure. PMID:11289617

  6. Intraoperative Spectroscopy with Ultrahigh Sensitivity for Image-Guided Surgery of Malignant Brain Tumors.

    PubMed

    Kairdolf, Brad A; Bouras, Alexandros; Kaluzova, Milota; Sharma, Abhinav K; Wang, May Dongmei; Hadjipanayis, Constantinos G; Nie, Shuming

    2016-01-01

    Intraoperative cancer imaging and fluorescence-guided surgery have attracted considerable interest because fluorescence signals can provide real-time guidance to assist a surgeon in differentiating cancerous and normal tissues. Recent advances have led to the clinical use of a natural fluorophore called protoporphyrin IX (PpIX) for image-guided surgical resection of high-grade brain tumors (glioblastomas). However, traditional fluorescence imaging methods have only limited detection sensitivity and identification accuracy and are unable to detect low-grade or diffuse infiltrating gliomas (DIGs). Here we report a low-cost hand-held spectroscopic device that is capable of ultrasensitive detection of protoporphyrin IX fluorescence in vivo, together with intraoperative spectroscopic data obtained from both animal xenografts and human brain tumor specimens. The results indicate that intraoperative spectroscopy is at least 3 orders of magnitude more sensitive than the current surgical microscopes, allowing ultrasensitive detection of as few as 1000 tumor cells. For detection specificity, intraoperative spectroscopy allows the differentiation of brain tumor cells from normal brain cells with a contrast signal ratio over 100. In vivo animal studies reveal that protoporphyrin IX fluorescence is strongly correlated with both MRI and histological staining, confirming that the fluorescence signals are highly specific to tumor cells. Furthermore, ex vivo spectroscopic studies of excised brain tissues demonstrate that the hand-held spectroscopic device is capable of detecting diffuse tumor margins with low fluorescence contrast that are not detectable with current systems in the operating room. These results open new opportunities for intraoperative detection and fluorescence-guided resection of microscopic and low-grade glioma brain tumors with invasive or diffusive margins. PMID:26587976

  7. Detection and identification of oral anaerobes in intraoperative bronchial fluids of patients with pulmonary carcinoma.

    PubMed

    Hasegawa, Ayako; Sato, Takuichi; Hoshikawa, Yasushi; Ishida, Naoko; Tanda, Naoko; Kawamura, Yoshiaki; Kondo, Takashi; Takahashi, Nobuhiro

    2014-07-01

    Postoperative pneumonia may occur when upper respiratory tract protective reflexes such as cough and/or swallowing reflexes are impaired; thus, silent aspiration of oral bacteria may be a causative factor in postoperative pneumonia. This study aimed to quantify and identify bacteria in intraoperative bronchial fluids and to evaluate the relationship between impairment of cough/swallowing reflexes and silent aspiration of oral bacteria in elderly patients. After obtaining informed consent, cough and swallowing reflexes were assessed using an ultrasonic nebulizer and a nasal catheter, respectively. Using a micro-sampling probe, intraoperative bronchial fluids were collected from nine subjects with pulmonary carcinoma and cultured anaerobically on blood agar plates. After 7 days, CFUs were counted and isolated bacteria were identified by 16S rRNA gene sequencing. Four subjects (aged 71.0 ± 8.4 years) had impaired swallowing reflexes with normal cough reflexes, whereas five subjects (73.6 ± 6.5 years) had normal cough and swallowing reflexes. The bacterial counts (mean CFU ± SD) tended to be higher in intraoperative bronchial fluids of subjects with impaired swallowing reflexes ([5.1 ± 7.7] × 10(5)) than in those of subjects with normal reflexes ([1.2 ± 1.9] × 10(5)); however, this difference was not statistically significant. Predominant isolates from intraoperative bronchial fluids were Streptococcus (41.8%), Veillonella (11.4%), Gemella (8.9%), Porphyromonas (7.6%), Olsenella (6.3%) and Eikenella (6.3%). These findings indicate that intraoperative bronchial fluids contain bacteria, probably derived from the oral microbiota, and suggest that silent aspiration of oral bacteria occurs in elderly patients irrespective of impairment of swallowing reflex. PMID:24818822

  8. Surgical decompression coupled with diagnostic dynamic intraoperative angiography for bow hunter's syndrome

    PubMed Central

    Nguyen, Ha Son; Doan, Ninh; Eckardt, Gerald; Pollock, Glen

    2015-01-01

    Background: Bow hunter's syndrome, also known as rotational vertebrobasilar insufficiency, arises from mechanical compression of the vertebral artery during the neck rotation. Surgical options have been the mainstay treatment of choice. Postoperative imaging is typically used to assess adequate decompression. On the other hand, intraoperative assessment of decompression has been rarely reported. Case Description: A 52-year-old male began to see “black spots,” and experienced presyncope whenever he rotated his head toward the right. The patient ultimately underwent a dynamic diagnostic cerebral angiogram, which revealed a dominant right vertebral artery and complete proximal occlusion of the right vertebral artery with the head rotated toward the right. Subsequently, the patient underwent an anterior transcervical approach to the right C6/C7 transverse process. The bone removal occurred along with the anterior wall of the C6 foramen transversarium, followed by the upper portion of the anterior C6 body medially, and the transverse process of C6 laterally. An oblique osseofibrous band was noted to extend across the vertebral artery; it was dissected and severed. An intraoperative cerebral angiogram confirmed no existing compression of the vertebral artery with the head rotated toward the right. The patient recovered from surgery without issues; he denied recurrence of preoperative symptoms at follow-up. Conclusions: The authors report the third instance where intraoperative dynamic angiography was employed with good outcomes. Although intraoperative cerebral angiography is an invasive procedure, which prompts additional risks, the authors believe the modality affords better, real-time visualization of the vertebral artery, allowing for assessment of the adequacy of the decompression. This advantage may reduce the probability for a second procedure, which has its own set of risks, and may counteract the risks involved with intraoperative dynamic angiography. PMID:26487972

  9. Strategy of Surgical Resection for Glioma Based on Intraoperative Functional Mapping and Monitoring

    PubMed Central

    TAMURA, Manabu; MURAGAKI, Yoshihiro; SAITO, Taiichi; MARUYAMA, Takashi; NITTA, Masayuki; TSUZUKI, Shunsuke; ISEKI, Hiroshi; OKADA, Yoshikazu

    2015-01-01

    A growing number of papers have pointed out the relationship between aggressive resection of gliomas and survival prognosis. For maximum resection, the current concept of surgical decision-making is in “information-guided surgery” using multimodal intraoperative information. With this, anatomical information from intraoperative magnetic resonance imaging (MRI) and navigation, functional information from brain mapping and monitoring, and histopathological information must all be taken into account in the new perspective for innovative minimally invasive surgical treatment of glioma. Intraoperative neurofunctional information such as neurophysiological functional monitoring takes the most important part in the process to acquire objective visual data during tumor removal and to integrate these findings as digitized data for intraoperative surgical decision-making. Moreover, the analysis of qualitative data and threshold-setting for quantitative data raise difficult issues in the interpretation and processing of each data type, such as determination of motor evoked potential (MEP) decline, underestimation in tractography, and judgments of patient response for neurofunctional mapping and monitoring during awake craniotomy. Neurofunctional diagnosis of false-positives in these situations may affect the extent of resection, while false-negatives influence intra- and postoperative complication rates. Additionally, even though the various intraoperative visualized data from multiple sources contribute significantly to the reliability of surgical decisions when the information is integrated and provided, it is not uncommon for individual pieces of information to convey opposing suggestions. Such conflicting pieces of information facilitate higher-order decision-making that is dependent on the policies of the facility and the priorities of the patient, as well as the availability of the histopathological characteristics from resected tissue. PMID:26185825

  10. On possible interactions between upper and lower atmosphere. [and warming trend in polar regions

    NASA Technical Reports Server (NTRS)

    Macdonald, B. C.; Reiter, E. R.

    1974-01-01

    Comparison of geomagnetic data with data on tropospheric and stratospheric circulation characteristics shows a statistically highly significant shrinking in areal extent of the stratospheric vortex from the third to the eight day following a geomagnetic storm. During the contraction of the polar vortex edge, the mean height of the vortex central contour decreases only slightly. This indicates that a stratospheric warming event is associated with a steepening of the contour gradient rather than a warming over the entire area of the stratospheric polar vortex. The troposphere reacts to these weak, but nevertheless significant stratospheric warming events by a shrinkage of the area of the 500-mb cold air pool. It is shown that the observed warming of the stratosphere that follows a geomagnetically disturbed key day cannot be explained by simple radiation absorption.

  11. Design and performance of combined infrared canopy and belowground warming in the B4WarmED (Boreal Forest Warming at an Ecotone in Danger) experiment.

    PubMed

    Rich, Roy L; Stefanski, Artur; Montgomery, Rebecca A; Hobbie, Sarah E; Kimball, Bruce A; Reich, Peter B

    2015-06-01

    Conducting manipulative climate change experiments in complex vegetation is challenging, given considerable temporal and spatial heterogeneity. One specific challenge involves warming of both plants and soils to depth. We describe the design and performance of an open-air warming experiment called Boreal Forest Warming at an Ecotone in Danger (B4WarmED) that addresses the potential for projected climate warming to alter tree function, species composition, and ecosystem processes at the boreal-temperate ecotone. The experiment includes two forested sites in northern Minnesota, USA, with plots in both open (recently clear-cut) and closed canopy habitats, where seedlings of 11 tree species were planted into native ground vegetation. Treatments include three target levels of plant canopy and soil warming (ambient, +1.7°C, +3.4°C). Warming was achieved by independent feedback control of voltage input to aboveground infrared heaters and belowground buried resistance heating cables in each of 72-7.0 m(2) plots. The treatments emulated patterns of observed diurnal, seasonal, and annual temperatures but with superimposed warming. For the 2009 to 2011 field seasons, we achieved temperature elevations near our targets with growing season overall mean differences (∆Tbelow ) of +1.84°C and +3.66°C at 10 cm soil depth and (∆T(above) ) of +1.82°C and +3.45°C for the plant canopies. We also achieved measured soil warming to at least 1 m depth. Aboveground treatment stability and control were better during nighttime than daytime and in closed vs. open canopy sites in part due to calmer conditions. Heating efficacy in open canopy areas was reduced with increasing canopy complexity and size. Results of this study suggest the warming approach is scalable: it should work well in small-statured vegetation such as grasslands, desert, agricultural crops, and tree saplings (<5 m tall). PMID:25640748

  12. Warming: mechanism and latitude dependence

    NASA Astrophysics Data System (ADS)

    Barkin, Yury

    2010-05-01

    Introduction. In the work it is shown, that in present warming of climate of the Earth and in style of its display a fundamental role the mechanism of the forced swing and relative oscillations of eccentric core of the Earth and its mantle plays. Relative displacements of the centers of mass of the core and the mantle are dictated by the features of orbital motions of bodies of solar system and nonineriality of the Earth reference frame (or ot the mantle) at the motion of the Earth with respect to a baricenter of solar system and at rotation of the planet. As a result in relative translational displacements of the core and the mantle the frequencies characteristic for orbital motion of all bodies of solar system, and also their combination are shown. Methods of a space geodesy, gravimetry, geophysics, etc. unequivocally and clearly confirm phenomenon of drift of the center of mass of the Earth in define northern direction. This drift is characterized by the significant velocity in about 5 mm/yr. The unique opportunity of its explanation consists in the natural assumption of existence of the unidirectional relative displacement (drift) the center of mass of the core and the center of mass of the mantle of the Earth. And this displacement (at superfluous mass of the core in 16.7 % from the mass of full the Earth) is characterized still more significant velocity in 2.6 cm/yr and occurs on our geodynamic studies in a direction to Taimyr peninsula. The dynamic explanation to century drift for today does not exist. It is possible to note, however, that data of observations of last years, indirectly testifying that similar drifts of the centers of mass in present epoch occur on other bodies of Solar system have been obtain: the Sun, Mars, the Titan, Enceladus, the Neptune, etc. We connect with mentioned phenomena the observed secular variations of natural processes on this celestial bodies. I.e. it is possible to assume, that observable eccentric positions of the centers of mass of some bodies of solar system and attributes of secular displacements of their centers of mass are universal and testify to relative translational displacements of shells of these bodies (such as the core, the mantle and others). And it means, that there is a highly effective mechanism of an active life of planets and satellites [1, 2]. This mechanism is distinct from the tidal mechanism of gravitational interaction of deformable celestial bodies. Its action is shown, for example, even in case if the core and the mantle are considered as absolutely rigid gravitating bodies, but separated by a is viscous-elastic layer. Classics of celestial mechanics did not consider gravitational interaction and relative translational displacement of the core and the mantle of the Earth. As our studies have shown the specified new mechanism is high energetic and allows to explain many of the phenomena earlier inaccessible to understanding in various geosciences, including climatology [1] - [5]. It has been shown, that secular changes in activity of all planetary processes on the Earth are connected with a secular drift of the core of the Earth, and are controlled by the core and are reflections and displays of the core drift [5]. It is naturally, that slow climatic changes are connected with drift of the core, with induced by this drift inversion changes in an atmosphere, ocean, with thermodynamic variations of state of layer D ', with changes and variations in mantle convection and in plume activity of the Earth. The drift of the core controls a transmission of heat in the top layers of the mantle and on a surface of the Earth, organizes volcanic and seismic activity of the Earth in planetary scale. The mechanism of a warming up of layers of the mantle and cyclic inversion changes of a climate. According to a developed geodynamic model all layers of the mantle at oscillations and motions of the core under action of its gravitational attraction test wide class of inversion deformations [1]. Thus the part of energy of deformations passes in heat by virtue of dissipation properties of the mantle. Than more intensively oscillations of the core, the more amplitudes of these oscillations, the occur the specified thermal transformations more intensively. As relative displacements of the core have cyclic character, because of cyclic influences on the core-mantle system of external celestial bodies also a formation of heat flows and warmed plume materials (substances) will have also cyclic character. In particular orbital perturbations with Milankovitch's periods in 100 kyr, 41 kyr, etc. will be precisely reflected in variations of the specified thermal flows and, accordingly, a planetary climate. In it the essence of occurrence of cycles of congelations on the Earth [3] consists. If during any period of time the core behaves passively, amplitudes of its oscillations are small the thermal flows to a surface of a planet will be decrease. This geodynamic conditions corresponds to the periods of a cold snap. And on the contrary, if the core and mantle interact actively and make significant oscillations the thermal flows to a surface of a planet accrues. This geodynamic state corresponds to the periods of warming. At drift of the core to the north and its oscillations with accrueing amplitude (for example, in present period) submission of heat in the top layers of the mantle will accrue. It is warmly allocated in all layers of the mantle deformed by an attraction of the drifting and oscillating core. But a base layer is the layer D" ("kitchen of plume-tectonics"). As we know the two mechanisms work for warm redistribution into the Earth. First is a mechanism of convection. In our geodynamical model it has forced nature and is organized and controlled by gravitational action of external celestial bodies and as result has cyclical character. Second mechanism is a plume mechanism which organizes the warmed masses redistributions in higher levels of the mantle, on a bottom of ocean and on a surface of the Earth. In accordance with our geodynamical model mentioned redistribution of warmed mass also has forced character. It is organized and controlled by gravitational cyclic action of the external celestial bodies on core-mantle system. N/S inversion of the natural processes. Reliable an attribute of influence of oscillations of the core on a variation of natural processes is their property of inversion when, for example, activity of process accrues in northern hemisphere and decreases in a southern hemisphere. Such contrast secular changes in northern and southern (N/S) hemispheres have been predicted on the base of geodynamic model [1] and revealed according to observations: from gravimetry measurements of a gravity; in determination of a secular trend of a sea level, as global, and in northern and southern hemispheres; in redistribution of air masses; in geodetic measurements of changes of average radiuses of northern and southern hemispheres; in contrast changes of physical fields, for example, streams of heat, currents and circulation at ocean and an atmosphere, etc. [5]. The geodynamic mechanism [1] also unequivocally specifies, that the secular trend in global climatic characteristics of the Earth, and also inversion and asymmetric tendencies of change of a climate, in its northern and southern hemispheres in present period should be observed. The hemispherical asymmetry of global heat flows. In the paper [6] authors have shown that the mean heat flow of the Southern Hemisphere is 99.3 mW/m2, significantly higher than that of the Northern Hemisphere (74.0 mW/m2). The mantle heat loss from the Southern Hemisphere is 22.1 × 1012 W, as twice as that from the Northern Hemisphere (10.8 × 1012 W). The authors believe that this hemispherical asymmetry of global heat loss is originated by the asymmetry of geographic distribution of continents and oceans. In accordance with our geodynamical model discussed assymmetry of heat flows distribution with respect the Earth's hemispheres in first caused by eccentric position of the Earth core with respect to the mantle (displaced in present geological epoch in direction to Brasil). Of course the asymmetric distribution of heat loss is a long-term phenomenon in the geological history. But in present epoch due to drift of the core to the North we must observe some increasing of the heat flow of the Northern hemisphere and decreasing of the heat flow of the Southern hemisphere. In reality mentioned changes of heat flows are contrast (asymmetrical) and can have general tendency of increasing heat flows in both hemispheres (due to activization of relative oscillations of the core and mantle relatively polar axis). Contrast secular warming of Northern and Southern hemispheres of the Earth in present epoch. Dependence of warming from latitude. And warm flows are asymmetrically, more intensively warm is redistributed in northern hemisphere of the Earth and less intensively in a southern hemisphere. From here it follows, that the phenomenon of more intensive warming up of northern hemisphere, rather than southern in present period should be observed. Data of climatic observations (in first temperature trends for various latitude belts). More detailed analysis shows, that the phenomenon of warming in different form is shown in various latitudinal belts of the Earth. This phenomenon is more clearly shown in latitudinal belts further situated on latitude from South Pole, i.e. in high northern latitudes. Really, the trend of increase of temperature in northern hemisphere is characterized by greater rate, than a trend of temperature in a southern hemisphere. And not only trend components of temperatures increase with increasing of latitudes from southern pole to northern pole, but also amplitudes of decade fluctuations of temperature in high northern breadthes are more bigger than in southern hemisphere. Thus again it is necessary to expect a contrast and asymmetry in decade variations of temperatures in northern and southern hemispheres (smaller variations in a southern hemisphere). References [1] Barkin Yu.V. (2002) An explanation of endogenous activity of planets and satellites and its cyclisity. Isvestia sekcii nauk o Zemle Rossiiskoi akademii ectestvennykh nauk. Vyp. 9, M., VINITI, pp. 45-97. In Russian. [2] Barkin Yu.V. (2009) Moons and planets: mechanism of their life. Proceedings of International Conference 'Astronomy and World Heritage: across Time and Continents' (Kazan, 19-24 August 2009). KSU, pp. 142-161. [3] Barkin Yu.V. (2004) Dynamics of the Earth shells and variations of paleoclimate. Proceedings of Milutin Milankovitch Anniversary Symposium 'Paleoclimate and the Earth climate system' (Belgrade, Serbia, 30 August - 2 September, 2004). Belgrade, Serbian Academy of Sciences and Art, pp. 161-164. [4] Barkin Yu.V. (2007) Inversion of periodic and trend variations of climate in opposite hemispheres of the Earth and their mechanism. Proceedings of IUGG XXIV General Assembly, Perugia, Italy 2007: Earth: Our Changing Planet (Perugia, Italy, July 2-13, 2007) (P) - IAPSO, JPS001 'Interannual and Interdecadal Climate Variability', p. 1674. www. iugg2007perugia.it. [5] Barkin Yu.V. (2008) Secular polar drift of the core in present epoch: geodynamical and geophysical consequences and confirmations. General and regional problems of tectonics and geodynamics. Materials of XLI Tectonic Conference. V. 1. -M.:GEOS. p. 55-59. In Russian. [6] Yang Wang, Jiyang Wangand Zongji Ma (1998) On the asymmetric distribution of heat loss from the Earth's interior. Chinese Science Bulletin, Volume 43, Number 18 , p. 1566-1570.

  13. In vivo intra-operative breast tumor margin detection using a portable OCT system with a handheld surgical imaging probe

    NASA Astrophysics Data System (ADS)

    Erickson-Bhatt, Sarah J.; Nolan, Ryan; Shemonski, Nathan D.; Adie, Steven G.; Putney, Jeffrey; Darga, Donald; McCormick, Daniel T.; Cittadine, Andrew; Marjanovic, Marina; Chaney, Eric J.; Monroy, Guillermo L.; South, Fredrick; Carney, P. Scott; Cradock, Kimberly A.; Liu, Z. George; Ray, Partha S.; Boppart, Stephen A.

    2014-02-01

    Breast-conserving surgery is a frequent option for women with stage I and II breast cancer, and with radiation treatment, can be as effective as a mastectomy. However, adequate margin detection remains a challenge, and too often additional surgeries are required. Optical coherence tomography (OCT) provides a potential method for real-time, high-resolution imaging of breast tissue during surgery. Intra-operative OCT imaging of excised breast tissues has been previously demonstrated by several groups. In this study, a novel handheld surgical probe-based OCT system is introduced, which was used by the surgeon to image in vivo, within the tumor cavity, and immediately following tumor removal in order to detect the presence of any remaining cancer. Following resection, study investigators imaged the excised tissue with the same probe for comparison. We present OCT images obtained from over 15 patients during lumpectomy and mastectomy surgeries. Images were compared to post-operative histopathology for diagnosis. OCT images with micron scale resolution show areas of heterogeneity and disorganized features indicative of malignancy, compared to more uniform regions of normal tissue. Video-rate acquisition shows the inside of the tumor cavity as the surgeon sweeps the probe along the walls of the surgical cavity. This demonstrates the potential of OCT for real-time assessment of surgical tumor margins and for reducing the unacceptably high re-operation rate for breast cancer patients.

  14. Contribution of intraoperative electrical stimulations in surgery of low grade gliomas: a comparative study between two series without (1985–96) and with (1996–2003) functional mapping in the same institution

    PubMed Central

    Duffau, H; Lopes, M; Arthuis, F; Bitar, A; Sichez, J; Van Effenterre, R; Capelle, L

    2005-01-01

    Objectives: Despite the growing use of intraoperative functional mapping in supratentorial low grade glioma (LGG) surgery, few studies have compared series of patients operated on without and with direct electrical stimulation (DES) by the same team. The present study compared the rate of LGG surgery performed in eloquent areas, the rate of postoperative sequelae, and the quality of resection during two consecutive periods in the same department—the first without and the second with the use of intraoperative electrophysiology. Methods: Between 1985 and 1996, 100 patients harbouring a supratentorial LGG underwent surgery with no functional mapping (S1). Between 1996 and 2003, 122 patients were operated on in the same department for a supratentorial LGG using intraoperative cortico-subcortical DES (S2). Results: Comparison between the two series showed that 35% of LGGs were operated on in eloquent areas in S1 versus 62% in S2 (p<0.0001), with 17% severe permanent deficits in S1 versus 6.5% in S2 (p<0.019). On postoperative MRI, 37% of resections were subtotal and 6% total in S1 versus 50.8% and 25.4%, respectively, in S2 (p<0.001). In both groups, survival was significantly related to the quality of resection. Conclusions: The results of the present study allow, for the first time, quantification of the contribution of intraoperative DES in LGG resection. Indeed, the use of this method leads to the extension of indications of LGG surgery within eloquent areas; to a decrease in the risk of sequelae; and to improvement of the quality of tumour resection, with an impact on survival. PMID:15897509

  15. Global Warming: Understanding and Teaching the Forecast.

    ERIC Educational Resources Information Center

    Andrews, Bill

    1994-01-01

    A resource for the teaching of the history and causes of climate change. Discusses evidence of climate change from the Viking era, early ice ages, the most recent ice age, natural causes of climate change, human-made causes of climate change, projections of global warming, and unequal warming. (LZ)

  16. Global Warming: Understanding and Teaching the Forecast.

    ERIC Educational Resources Information Center

    Andrews, Bill

    1995-01-01

    A resource for teaching about the consequences of global warming. Discusses feedback from the temperature increase, changes in the global precipitation pattern, effects on agriculture, weather extremes, effects on forests, effects on biodiversity, effects on sea levels, and actions which will help the global community cope with global warming. (LZ)

  17. Greenhouse warming and the tropical water budget

    NASA Technical Reports Server (NTRS)

    Betts, Alan K.

    1990-01-01

    The present work takes issue with some of the theses of Lindzen's (1990) work on global warming, arguing in particular that Lindzen's work is hampered by the use of oversimplified models. Lindzen then presents a detailed reply to these arguments, emphasizing the fundamental importance of the upper tropospheric water-vapor budget to the question of global warming.

  18. Exploring the Sociopolitical Dimensions of Global Warming

    ERIC Educational Resources Information Center

    Sadler, Troy D.; Klosterman, Michelle L.

    2009-01-01

    The authors present an activity to help high school students conceptualize the sociopolitical complexity of global warming through an exploration of varied perspectives on the issue. They argue that socioscientific issues such as global warming present important contexts for learning science and that the social and political dimensions of these…

  19. Global Warming: Lessons from Ozone Depletion

    ERIC Educational Resources Information Center

    Hobson, Art

    2010-01-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of…

  20. Global Warming: How Much and Why?

    ERIC Educational Resources Information Center

    Lanouette, William

    1990-01-01

    Summarizes the history of the study of global warming and includes a discussion of the role of gases, like carbon dioxide, methane, and chlorofluorocarbon (CFC). Discusses modern research on the global warming, including computer modelling and the super-greenhouse effect. (YP)

  1. Nonlinear electron oscillations in a warm plasma

    SciTech Connect

    Sarkar, Anwesa; Maity, Chandan; Chakrabarti, Nikhil

    2013-12-15

    A class of nonstationary solutions for the nonlinear electron oscillations of a warm plasma are presented using a Lagrangian fluid description. The solution illustrates the nonlinear steepening of an initial Gaussian electron density disturbance and also shows collapse behavior in time. The obtained solution may indicate a class of nonlinear transient structures in an unmagnetized warm plasma.

  2. Global Warming: Lessons from Ozone Depletion

    ERIC Educational Resources Information Center

    Hobson, Art

    2010-01-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of

  3. Warming of Water in a Glass

    ERIC Educational Resources Information Center

    Paulins, Paulis; Krauze, Armands; Ozolinsh, Maris; Muiznieks, Andris

    2016-01-01

    The article focuses on the process of water warming from 0 °C in a glass. An experiment is performed that analyzes the temperature in the top and bottom layers of water during warming. The experimental equipment is very simple and can be easily set up using devices available in schools. The temperature curves obtained from the experiment help us…

  4. Exploring the Sociopolitical Dimensions of Global Warming

    ERIC Educational Resources Information Center

    Sadler, Troy D.; Klosterman, Michelle L.

    2009-01-01

    The authors present an activity to help high school students conceptualize the sociopolitical complexity of global warming through an exploration of varied perspectives on the issue. They argue that socioscientific issues such as global warming present important contexts for learning science and that the social and political dimensions of these

  5. Cryosphere: Warming ocean erodes ice sheets

    NASA Astrophysics Data System (ADS)

    Kusahara, Kazuya

    2016-01-01

    Antarctic ice sheets are a key player in sea-level rise in a warming climate. Now an ice-sheet modelling study clearly demonstrates that an Antarctic ice sheet/shelf system in the Atlantic Ocean will be regulated by the warming of the surrounding Southern Ocean, not by marine-ice-sheet instability.

  6. Turkish Students' Ideas about Global Warming

    ERIC Educational Resources Information Center

    Kilinc, Ahmet; Stanisstreet, Martin; Boyes, Edward

    2008-01-01

    A questionnaire was used to explore the prevalence of ideas about global warming in Year 10 (age 15-16 years) school students in Turkey. The frequencies of individual scientific ideas and misconceptions about the causes, consequences and "cures" of global warming were identified. In addition, several general findings emerged from this study.…

  7. Warm Pressurant Gas Effects on the Liquid Hydrogen Bubble Point

    NASA Technical Reports Server (NTRS)

    Hartwig, Jason W.; McQuillen, John B.; Chato, David J.

    2013-01-01

    This paper presents experimental results for the liquid hydrogen bubble point tests using warm pressurant gases conducted at the Cryogenic Components Cell 7 facility at the NASA Glenn Research Center in Cleveland, Ohio. The purpose of the test series was to determine the effect of elevating the temperature of the pressurant gas on the performance of a liquid acquisition device. Three fine mesh screen samples (325 x 2300, 450 x 2750, 510 x 3600) were tested in liquid hydrogen using cold and warm noncondensible (gaseous helium) and condensable (gaseous hydrogen) pressurization schemes. Gases were conditioned from 0 to 90 K above the liquid temperature. Results clearly indicate a degradation in bubble point pressure using warm gas, with a greater reduction in performance using condensable over noncondensible pressurization. Degradation in the bubble point pressure is inversely proportional to screen porosity, as the coarsest mesh demonstrated the highest degradation. Results here have implication on both pressurization and LAD system design for all future cryogenic propulsion systems. A detailed review of historical heated gas tests is also presented for comparison to current results.

  8. Warm Disks from Giant Impacts

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-10-01

    In the process of searching for exoplanetary systems, weve discovered tens of debris disks close around distant stars that are especially bright in infrared wavelengths. New research suggests that we might be looking at the late stages of terrestrial planet formation in these systems.Forming Terrestrial PlanetsAccording to the widely-accepted formation model for our solar-system, protoplanets the size of Mars formed within a protoplanetary disk around our Sun. Eventually, the depletion of the gas in the disk led the orbits of these protoplanets to become chaotically unstable. Finally, in the giant impact stage, many of the protoplanets collided with each other ultimately leading to the formation of the terrestrial planets and their moons as we know them today.If giant impact stages occur in exoplanetary systems, too leading to the formation of terrestrial exoplanets how would we detect this process? According to a study led by Hidenori Genda of the Tokyo Institute of Technology, we might be already be witnessing this stage in observations of warm debris disks around other stars. To test this, Genda and collaborators model giant impact stages and determine what we would expect to see from a system undergoing this violent evolution.Modeling CollisionsSnapshots of a giant impact in one of the authors simulations. The collision causes roughly 0.05 Earth masses of protoplanetary material to be ejected from the system. Click for a closer look! [Genda et al. 2015]The collaborators run a series of simulations evolving protoplanetary bodies in a solar system. The simulations begin 10 Myr into the lifetime of the solar system, i.e., after the gas from the protoplanetary disk has had time to be cleared and the protoplanetary orbits begin to destabilize. The simulations end when the protoplanets are done smashing into each other and have again settled into stable orbits, typically after ~100 Myr.The authors find that, over an average giant impact stage, the total amount of mass ejected from colliding protoplanets is typically around 0.4 Earth masses. This mass is ejected in the form of fragments that then spread into the terrestrial planet region around the star. The fragments undergo cascading collisions as they orbit, forming an infrared-emitting debris disk at ~1 AU from the star.The authors then calculate the infrared flux profile expected from these simulated disks. They show that the warm disks can exist and radiate for up to ~100 Myr before the fragments are smashed into micrometer-sized pieces small enough to be blown out of the solar system by radiation pressure.The Spitzer Space Telescope has, thus far, observed tens of warm-debris-disk signatures roughly consistent with the authors predictions, primarily located at roughly 1 AU around stars with ages of 10100 Myr. This region is near the habitable zone of these stars, which makes it especially interesting that these systems may currently be undergoing a giant impact stage perhaps on the way to forming terrestrial planets.CitationH. Genda et al 2015 ApJ 810 136. doi:10.1088/0004-637X/810/2/136

  9. Global warming, insurance losses and financial industry

    SciTech Connect

    Low, N.C.

    1996-12-31

    Global warming causes extremely bad weather in the near term. They have already caught the attention of the insurance industry, as they suffered massive losses in the last decade. Twenty-one out of the 25 largest catastrophes in the US, mainly in the form of hurricanes have occurred in the last decade. The insurance industry has reacted by taking the risk of global warming in decisions as to pricing and underwriting decisions. But they have yet to take a more active role in regulating the factors that contributes to global warming. How global warming can impact the financial industry and the modern economy is explored. Insurance and modern financial derivatives are key to the efficient functioning of the modern economy, without which the global economy can still function but will take a giant step backward. Any risk as global warming that causes economic surprises will hamper the efficient working of the financial market and the modern economy.

  10. Intra-operative visualization of brain tumors with 5-aminolevulinic acid-induced fluorescence.

    PubMed

    Widhalm, Georg

    2014-01-01

    Precise histopathological diagnosis of brain tumors is essential for the correct patient management. Furthermore, complete resection of brain tumors is associated with an improved patient prognosis. However, histopathological undergrading and incomplete tumor removal are not uncommon, especially due to insufficient intra-operative visualization of brain tumor tissue. The fluorescent dye 5-aminolevulinic acid (5-ALA) is currently applied for fluorescence-guided resections of high-grade gliomas. The value of 5-ALA-induced protoporphyrin (PpIX) fluorescence for intra-operative visualization of other tumors than high-grade gliomas remains unclear. Within the frame of this thesis, we found a significantly higher rate of complete resections of our high-grade gliomas as compared to control cases by using the newly established 5-ALA fluorescence technology at our department. Additionally, we showed that MRI spectroscopy-based chemical shift imaging (CSI) is capable to identify intratumoral high-grade glioma areas (= anaplastic foci) during navigation guided resections to avoid histopathological undergrading. However, the accuracy of navigation systems with integrated pre-operative imaging data such as CSI declines during resections due to intra-operative brainshift. In two further studies, we found that 5-ALA induced PpIX fluorescence is capable as a novel intra-operative marker to detect anaplastic foci within initially suspected low-grade gliomas independent of brainshift. Finally, we showed that the application of 5-ALA is also of relevance in needle biopsies for intra-operative identification of representative brain tumor tissue. These data indicate that 5-ALA is not only of major importance for resection of high-grade gliomas, but also for intra-operative visualization of anaplastic foci as well as representative brain tumor tissue in needle biopsies unaffected by brainshift. Consequently, this new technique might become a novel standard in brain tumor surgery that optimizes the patient management and improves the patient prognosis by maximizing the extent of tumor resection and enabling a precise histopathological tumor diagnosis. PMID:24986206

  11. Comparing the model-simulated global warming signal to observations using empirical estimates of unforced noise

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The comparison of observed global mean surface air temperature (GMT) change to the mean change simulated by climate models has received much attention. For a given global warming signal produced by a climate model ensemble, there exists an envelope of GMT values representing the range of possible un...

  12. Global warming: The complete briefing

    SciTech Connect

    Houghton, J.

    1994-12-31

    John Houghton has drawn on the exhaustive efforts of the Intergovernmental Panel on Climate Change (IPCC) to produce a notably compact, impeccably complete and authoritative, meticulously balanced, and lucidly presented guide to the complex yet vital issue of global warming. Its subtitle is not mere hyperbole: this truly is a complete briefing. Certainly, one could not ask for a more authoritative brief: Houghton has led an imposing series of national and international efforts relating to climate, including the most recent scientific assessments of the IPCC. Citing many concrete examples, Houghton begins by convincing that climate truly is important to humankind and that climate is far from constant. He then elucidates the mechanisms that maintain the benign climate of our planet, providing in the process, for example, the most accurate explanation of the natural greenhouse effect that has yet appeared in print. He then treats the individual greenhouse gases responsible for maintaining the earth`s warmth and presents projections of their probable future concentrations as influenced by human activities. Further chapters deal with conclusions drawn from climate models, estimates of the impacts on human activities, and possible policies and actions to mitigate or alleviate the changes and their consequences.

  13. Thermal pollution causes global warming

    NASA Astrophysics Data System (ADS)

    Nordell, Bo

    2003-09-01

    Over longer time-scales there is no net heat inflow to Earth since incoming solar energy is re-emitted at exactly the same rate. To maintain Earth's thermal equilibrium, however, there must be a net outflow equal to the geothermal heat flow. Performed calculations show that the net heat outflow in 1880 was equal to the geothermal heat flow, which is the only natural net heat source on Earth. Since then, heat dissipation from the global use of nonrenewable energy sources has resulted in additional net heating. In, e.g. Sweden, which is a sparsely populated country, this net heating is about three times greater than the geothermal heat flow. Such thermal pollution contributes to global warming until the global temperature has reached a level where this heat is also emitted to space. Heat dissipation from the global use of fossil fuels and nuclear power is the main source of thermal pollution. Here, it was found that one third of current thermal pollution is emitted to space and that a further global temperature increase of 1.8 C is required until Earth is again in thermal equilibrium.

  14. Global warming and reproductive health.

    PubMed

    Potts, Malcolm; Henderson, Courtney E

    2012-10-01

    The largest absolute numbers of maternal deaths occur among the 40-50 million women who deliver annually without a skilled birth attendant. Most of these deaths occur in countries with a total fertility rate of greater than 4. The combination of global warming and rapid population growth in the Sahel and parts of the Middle East poses a serious threat to reproductive health and to food security. Poverty, lack of resources, and rapid population growth make it unlikely that most women in these countries will have access to skilled birth attendants or emergency obstetric care in the foreseeable future. Three strategies can be implemented to improve women's health and reproductive rights in high-fertility, low-resource settings: (1) make family planning accessible and remove non-evidenced-based barriers to contraception; (2) scale up community distribution of misoprostol for prevention of postpartum hemorrhage and, where it is legal, for medical abortion; and (3) eliminate child marriage and invest in girls and young women, thereby reducing early childbearing. PMID:22883918

  15. Some economics of global warming

    SciTech Connect

    Schelling, T.C. )

    1992-03-01

    The greenhouse effect itself is simple enough to understand and is not in any real dispute. What is in dispute is its magnitude over the coming century, its translation into changes in climates around the globe, and the impacts of those climate changes on human welfare and the natural environment. These are beyond the professional understanding of any single person. The sciences involved are too numerous and diverse. Demography, economics, biology, and the technology sciences are needed to project emissions; atmospheric chemistry, oceanography, biology, and meteorology are needed to translate emissions into climates; biology, agronomy, health sciences, economics, sociology, and glaciology are needed to identify and assess impacts on human societies and natural ecosystems. And those are not all. There are expert judgments on large pieces of the subject, but no single person clothed in this panoply of disciplines has shown up or is likely to. This article makes an attempt to forecast the economic and social consequences of global warming due to anthropogenic greenhouse gases, and attempting to prevent it.

  16. Galaxy formation in warm dark matter cosmology

    NASA Astrophysics Data System (ADS)

    Menci, N.; Fiore, F.; Lamastra, A.

    2012-04-01

    We investigate for the first time the effects of a warm dark matter (WDM) power spectrum on the statistical properties of galaxies using a semi-analytic model of galaxy formation. The WDM spectrum we adopt as a reference case is suppressed - compared to the standard cold dark matter (CDM) case - below a cut-off scale ≈1 Mpc corresponding (for thermal relic WDM particles) to a mass mX= 0.75 keV. This ensures consistency with present bounds provided by the microwave background Wilkinson Microwave Anisotropy Probe data and by the comparison of hydrodynamical N-body simulations with observed Lyman-α forest. We run our fiducial semi-analytic model with such a WDM spectrum to derive galaxy luminosity functions (in B, UV and K bands) and the stellar mass distributions over a wide range of cosmic epochs, to compare with recent observations and with the results in the CDM case. The predicted colour distribution of galaxies in the WDM model is also checked against the data. When compared with the standard CDM case, the luminosity and stellar mass distributions we obtain assuming a WDM spectrum are characterized by (i) flattening of the faint-end slope and (ii) sharpening of the cut-off at the bright end for z≲ 0.8. We discuss how the former result is directly related to the smaller number of low-mass haloes collapsing in the WDM scenario, while the latter is related to the smaller number of satellite galaxies accumulating in massive haloes at a low redshift, thus suppressing the accretion of small lumps on the central, massive galaxies. These results shows how adopting a WDM power spectrum may contribute to solving two major problems of CDM galaxy formation scenarios, namely, the excess of predicted faint (low-mass) galaxies at low and - most of all - high redshifts, and the excess of bright (massive) galaxies at low redshifts.

  17. Intraoperative photodynamic therapy on spontaneous canine nasal tumors

    NASA Astrophysics Data System (ADS)

    Fonda, Diego; Mortellaro, Carlo M.; Romussi, Stefano; Taroni, Paola; Cubeddu, Rinaldo

    1994-09-01

    Promising results obtained by photodynamic therapy (PDT) with porphyrins on superficial spontaneous canine tumors suggested the experiment of this technique on intracavitary tumors, specifically at the endonasal site. The supposed neoplastic residual bed was irradiated directly during surgery at the end of the debulking. Five dogs referred to the surgical department of the veterinary school, University of Milan and affected by endonasal neoplasias were submitted to PDT after radiologic and cyto-histologic diagnosis and TNM stadiation. All the selected tumors were included in the clinical stage 1 (T1NOMO). Mean and median survival time (from the day of treatment) were 11.6 - 5.4 and 12 months, respectively. Different staging of the treated tumors limits the possibility of an objective comparison with other alternative therapeutic procedures.

  18. Relative roles of differential SST warming, uniform SST warming and land surface warming in determining the Walker circulation changes under global warming

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Li, Tim

    2016-04-01

    Most of CMIP5 models projected a weakened Walker circulation in tropical Pacific, but what causes such change is still an open question. By conducting idealized numerical simulations separating the effects of the spatially uniform sea surface temperature (SST) warming, extra land surface warming and differential SST warming, we demonstrate that the weakening of the Walker circulation is attributed to the western North Pacific (WNP) monsoon and South America land effects. The effect of the uniform SST warming is through so-called "richest-get-richer" mechanism. In response to a uniform surface warming, the WNP monsoon is enhanced by competing moisture with other large-scale convective branches. The strengthened WNP monsoon further induces surface westerlies in the equatorial western-central Pacific, weakening the Walker circulation. The increase of the greenhouse gases leads to a larger land surface warming than ocean surface. As a result, a greater thermal contrast occurs between American Continent and equatorial Pacific. The so-induced zonal pressure gradient anomaly forces low-level westerly anomalies over the equatorial eastern Pacific and weakens the Walker circulation. The differential SST warming also plays a role in driving low-level westerly anomalies over tropical Pacific. But such an effect involves a positive air-sea feedback that amplifies the weakening of both east-west SST gradient and Pacific trade winds.

  19. Finite Element Simulations for Sheet Warm Hydroforming

    NASA Astrophysics Data System (ADS)

    Prete, A. Del; Papadia, G.; de Vitis, A. A.; Primo, T.

    2011-05-01

    The use of lightweight alloy offers significant potential to improve product performances. However, the application of formed lightweight alloy components in critical structures is restricted due to this material's low formability at room temperature and lack of knowledge for processing lightweight alloys at elevated temperature. Warm forming is becoming of great interest in order to increase the formability of these materials and many conventional processes are adapted including the temperature as a new parameter. In addition to this option, warm hydroforming technology for the lightweight materials is currently emerging to achieve reduced number of manufacturing steps and part consolidation. The warm hydroforming process makes use of the improved formability at elevated temperature and it also utilizes the fluid to transport the forming action as well as heat. In the present work, the authors have studied the warm hydroforming process using two different numerical approaches in order to simulate it. The first software is traditionally used in metal stamping simulations (also warm and hot) unlike the second. The analyzed material is an Al 6061 alloy 2,03 mm thick. Process responses such as: bulge height, thickness reduction and strain distribution have been evaluated different temperature levels (room temperature, equal to 23° C, 100° C and 200° C). The obtained results have been used to study the accuracy of the second software in sheet warm hydroforming simulation. The authors have also defined the more reliable numerical environment in order to develop material damage models in warm forming conditions.

  20. Intraoperative rupture of popliteal artery pseudoaneurysm secondary to distal femur osteochondroma: case report and review of the literature

    PubMed Central

    Hajji, Rita; Jiber, Hamid; Zrihni, Youssef; Zizi, Othman; Bouarroum, Abdellatif

    2013-01-01

    Vascular complications from osteochondroma are rare and include essentially stenosis, occlusion, and pseudoaneurysms. The authors report an original case of intraoperative rupture of undiagnosed popliteal artery pseudoaneurysm during resection surgery for a distal femur osteochondroma. PMID:24876908

  1. Mechanisms of delayed Southern Ocean warming

    NASA Astrophysics Data System (ADS)

    Armour, K.; Marshall, J.; Donohoe, A.; Scott, J. R.

    2013-12-01

    Delayed surface warming of the Southern Ocean (SO) is a robust feature of the climate response to greenhouse gas forcing. It is seen in in-situ and satellite-based observations, and is simulated within coupled atmosphere-ocean general circulation models (GCMs). The observed cooling and associated sea ice expansion around Antarctica in recent decades is in stark contrast to the rapid warming and sea ice loss seen in the Arctic, yet the processes responsible for these divergent behaviors are not well understood. The SO warming delay has been widely attributed to deep mixed layers and efficient deep ocean heat uptake processes, while the observed cooling is often attributed to changes in upper ocean stratification or surface winds. We argue here that while these mechanisms do play a role, delayed SO warming is primarily a consequence of the mean SO circulation: Ekman upwelling of unmodified water from depth acts to anchor sea surface temperatures over multi-centennial timescales; equatorward transport of surface waters acts to advect the anomalous temperature signal out of the SO, where it is subducted on the equatorward flank of the Antarctic Circumpolar Current, driving an anomalous northward ocean heat transport that largely balances the increased air-sea heat flux into the SO under global warming. We explore the relative roles of the mechanisms of delayed SO warming within a variety of GCMs and observations. The observed spatial structure of upper ocean and surface warming is found to be well represented by an ocean-only GCM forced radiatively at the surface, but with no changes in surface winds or salinity. Within this model framework, the active versus passive nature of ocean heat uptake, and its influence on SO circulation, is explored. We further consider the consequences of delayed SO warming for (i) changes in atmospheric meridional energy transport with global warming, and (ii) the global top-of-atmosphere energy budget, via the delayed activation of destabilizing SO radiative feedbacks.

  2. Significant Warming of the Antarctic Winter Troposphere

    NASA Astrophysics Data System (ADS)

    Turner, J.; Lachlan-Cope, T. A.; Colwell, S.; Marshall, G. J.; Connolley, W. M.

    2006-03-01

    We report an undocumented major warming of the Antarctic winter troposphere that is larger than any previously identified regional tropospheric warming on Earth. This result has come to light through an analysis of recently digitized and rigorously quality controlled Antarctic radiosonde observations. The data show that regional midtropospheric temperatures have increased at a statistically significant rate of 0.5° to 0.7° Celcius per decade over the past 30 years. Analysis of the time series of radiosonde temperatures indicates that the data are temporally homogeneous. The available data do not allow us to unambiguously assign a cause to the tropospheric warming at this stage.

  3. Definitive diagnosis of a duplicate gallbladder can only be made intraoperatively: report of a case.

    PubMed

    Ozaki, Nobuyuki; Hashimoto, Daisuke; Ikuta, Yoshiaki; Chikamoto, Akira; Takamori, Hiroshi; Baba, Hideo

    2014-08-01

    Duplicated gallbladders are rare congenital anomalies that are important in clinical practice as they may cause clinical, surgical, and diagnostic problems. Here, we describe the case of a 79-year-old female patient who presented with acute cholangitis. Abdominal ultrasonography, endoscopic ultrasonography, computed tomography, and magnetic resonance imaging revealed an intrahepatic cystic lesion, suggesting communication with the intrahepatic bile duct; no evidence of a polypoid lesion within the cystic lesion was observed. Based on these findings, intrahepatic cholangiectasis, intrahepatic bile duct cystadenoma, and the presence of a duplicated gallbladder were suspected, and surgery was performed. During surgery, a tube inserted into the common bile duct from a cystic duct facilitated intraoperative cholangiography, which indicated the presence of a duplicated gallbladder. Thus, we believe that a duplicated gallbladder should be an additional consideration when typical gallbladder disease symptoms are present under certain circumstances. A multimodal imaging approach can help to establish the diagnosis preoperatively or intraoperatively. PMID:26185884

  4. Controversies in the Anesthetic Management of Intraoperative Rupture of Intracranial Aneurysm

    PubMed Central

    Petropolis, Andrea; Wilkinson, Marshall; Sandu, Nora; Cappellani, Ronald B.

    2014-01-01

    Despite great advancements in the management of aneurysmal subarachnoid hemorrhage (SAH), outcomes following SAH rupture have remained relatively unchanged. In addition, little data exists to guide the anesthetic management of intraoperative aneurysm rupture (IAR), though intraoperative management may have a significant effect on overall neurological outcomes. This review highlights the various controversies related to different anesthetic management related to aneurysm rupture. The first controversy relates to management of preexisting factors that affect risk of IAR. The second controversy relates to diagnostic techniques, particularly neurophysiological monitoring. The third controversy pertains to hemodynamic goals. The neuroprotective effects of various factors, including hypothermia, various anesthetic/pharmacologic agents, and burst suppression, remain poorly understood and have yet to be further elucidated. Different management strategies for IAR during aneurysmal clipping versus coiling also need further attention. PMID:24723946

  5. Usefulness of Intraoperative Monitoring during Microsurgical Decompression of Cervicomedullary Compression Caused by an Anomalous Vertebral Artery

    PubMed Central

    Kim, Sung Tae; Jeong, Dong Mun; Lee, Kun Soo

    2014-01-01

    We report a case of cervicomedullary compression by an anomalous vertebral artery treated using microsurgical decompression with intraoperative monitoring. A 68-year-old woman presented with posterior neck pain and gait disturbance. MRI revealed multiple abnormalities, including an anomalous vertebral artery that compressed the spinal cord at the cervicomedullary junction. Suboccipital craniectomy with C1 laminectomy was performed. The spinal cord was found to be compressed by the vertebral arteries, which were retracted dorsolaterally. At that time, the somatosensory evoked potential (SSEP) changed. After release of the vertebral artery, the SSEP signal normalized instantly. The vertebral artery was then lifted gently and anchored to the dura. There was no other procedural complication. The patient's symptoms improved. This case demonstrates that intraoperative monitoring may be useful for preventing procedural complications during spinal cord microsurgical decompression. PMID:25628814

  6. [Intraoperative neuromonitoring of thyroid gland operations : Surgical standards and aspects of expert assessment].

    PubMed

    Dralle, H; Lorenz, K

    2010-07-01

    Intraoperative neuromonitoring (IONM) was introduced into thyroid surgery approximately 10 years ago for better identification of recurrent laryngeal nerve palsy. Since then several studies have been performed for evaluation of this new technology. IONM is superior to visual nerve identification alone for prediction of postoperative local cord function. Therefore, in bilateral procedures IONM enables intraoperative decision-making concerning resection of the second side. To avoid misinterpretation of the results of IONM a standardized approach including preoperative and postoperative laryngoscopy and preresection and postresection vagus stimulation is recommended. Trouble-shooting requires systematic checking of the device including control of electrode position (needle or tube electrodes). For expert assessment purposes documentation of the standardized application of IONM is of utmost importance. PMID:20517586

  7. Functional preoperative and intraoperative mapping and monitoring: increasing safety and efficacy in glioma surgery.

    PubMed

    Ottenhausen, Malte; Krieg, Sandro M; Meyer, Bernhard; Ringel, Florian

    2015-01-01

    Greater extent of resection (EOR) of low-grade gliomas is associated with improved survival. Proximity to eloquent cortical regions often limits resectability and elevates the risk of surgery-related deficits. Therefore, functional localization of eloquent cortex or subcortical fiber tracts can enhance the EOR and functional outcome. Imaging techniques such as functional MRI and diffusion tensor imaging fiber tracking, and neurophysiological methods like navigated transcranial magnetic stimulation and magnetoencephalography, make it possible to identify eloquent areas prior to resective surgery and to tailor indication and surgical approach but also to assess the surgical risk. Intraoperative monitoring with direct cortical stimulation and subcortical stimulation enables surgeons to preserve essential functional tissue during surgery. Through tailored pre- and intraoperative mapping and monitoring the EOR can be maximized, with reduced rates of surgery-related deficits. PMID:25552283

  8. An intraoperative probe combining positron detection and OCT imaging for ovarian cancer detection and characterization

    NASA Astrophysics Data System (ADS)

    Yang, Yi; Wang, Tianheng; Biswal, Nrusingh; Kumavor, Patrick; Wang, Xiaohong; Karimeddini, Mozafareddin; Vento, John; Sanders, Melinda; Brewer, Molly; Zhu, Quing

    2012-01-01

    In this paper, we report an intraoperative approach by combining optical coherence tomography (OCT) and position detection to detect and characterize ovarian cancers. A total of 18 ovaries were studied ex vivo. Based on histopathology result, they were classified into normal and malignant groups, respectively. On average positron count rate of 8.0-fold higher was found between malignant and normal ovaries. OCT imaging of ovaries revealed many detailed morphologic features that could be potentially valuable for detecting early malignant changes in ovarian tissue. Optical scattering coefficients of these ovaries were estimated from OCT A-lines. Normal ovarian tissue showed higher scattering coefficient than that of malignant ovarian tissue. Using a threshold of 2.00 mm-1 for all ovaries, a sensitivity of 100% and a specificity of 100% were achieved. This initial data shows our intraoperative probe based on OCT and positron detection has a great potential for ovarian cancer detection and characterization.

  9. Intraoperative management of heart-lung interactions: "from hypothetical prediction to improved titration".

    PubMed

    Ouattara, A; Dewitte, A; Rozé, H

    2014-01-01

    Extensive literature describes the suitability of dynamic parameters to predict responsiveness in fluid. However, based on heart-lung interactions, these parameters can have serious limitations, including the use of protective lung ventilation. Although the latter seems to be beneficial for healthy patients undergoing high-risk surgery, the intraoperative interpretation of dynamic parameters to predict fluid responsiveness can be hazardous. In this context, the attending physician could, alternatively, titrate the need of fluids with a small fluid challenge, which remains unaffected by low tidal volume, the presence of arrhythmia, or the presence of spontaneous ventilation. When intraoperative prediction of fluid responsiveness is required in mechanically ventilated patients, "improved" titration should be preferred to a hypothetical prediction. PMID:25127853

  10. Pelvic intraoperative neuromonitoring during robotic-assisted low anterior resection for rectal cancer.

    PubMed

    Grade, Marian; Beham, Alexander W; Schüler, P; Kneist, Werner; Ghadimi, B Michael

    2016-06-01

    While the oncological outcome of patients with rectal cancer has been considerably improved within the last decades, anorectal, urinary and sexual functions remained impaired at high levels, regardless of whether radical surgery was performed open or laparoscopically. Consequently, intraoperative monitoring of the autonomic pelvic nerves with simultaneous electromyography of the internal anal sphincter and manometry of the urinary bladder has been introduced to advance nerve-sparing surgery and to improve functional outcome. Initial results suggested that pelvic neuromonitoring may result in better functional outcomes. Very recently, it has also been demonstrated that minimally invasive neuromonitoring is technically feasible. Because, to the best of our knowledge, pelvic neuromonitoring has not been performed during robotic surgery, we report the first case of robotic-assisted low anterior rectal resection combined with intraoperative monitoring of the autonomic pelvic nerves. PMID:26705113

  11. Rat liver tolerance for partial resection and intraoperative radiation therapy: Regeneration is radiation dose dependent

    SciTech Connect

    Bossola, M.; Merrick, H.W.; Eltaki, A.; Bellantone, R.; Milligan, A.J.; Doglietto, G.B.; Conran, P.; Dobelbower, R.R. Jr.; Crucitti, F. )

    1990-11-01

    We studied the feasibility of delivering a large single dose of intraoperative radiation as an adjuvant to partial hepatic resection. Intraoperative radiation therapy (IORT) was delivered to the remaining liver of 84 rats after partial hepatectomy to determine the acute and chronic effects of treatment on blood chemistry values, histology, survival, hepatic regeneration, and cellular appearance of the normal liver. Transient elevations in SGOT, SGPT, and alkaline phosphatase were attributed both to hepatectomy and to liver parenchymal damage induced by IORT. Microscopic examination upon necropsy, performed at frequent intervals post-treatment revealed hepatic capsular thickening with some alteration of liver architecture mainly underneath the capsule, with localized inflammation and some areas of necrosis. Survival in all groups was 100% at 45 days. Liver weight increase proved to be dose-dependent and displayed a bisphasic pattern. This study demonstrated that IORT is a feasible adjunct to surgical resection of the liver in the rat model.

  12. Feasibility of cervical intramedullary diffuse glioma resection using intraoperative magnetic resonance imaging.

    PubMed

    Giordano, Mario; Gerganov, Venelin M; Metwali, Hussam; Fahlbusch, Rudolf; Samii, Amir; Samii, Madjid; Bertalanffy, Helmut

    2013-11-15

    Intraoperative magnetic resonance imaging (iopMRI) actually has an important role in the surgery of brain tumors, especially gliomas and pituitary adenomas. The aim of our work was to describe the advantages and drawbacks of this tool for the surgical treatment of cervical intramedullary gliomas. We describe two explicative cases including the setup, positioning, and the complete workflow of the surgical approach with intraoperative imaging. Even if the configuration of iopMRI equipment was originally designed for cranial surgery, we have demonstrated the feasibility of cervical intramedullary glioma resection with the aid of high-field iopMRI. This tool was extremely useful to evaluate the extent of tumor removal and to obtain a higher resection rate, but still need some enhancement in the configuration of the headrest coil and surgical table to allow better patient positioning. PMID:24233260

  13. Intraoperative measurement of parathyroid hormone: A Copernican revolution in the surgical treatment of hyperparathyroidism.

    PubMed

    Gioviale, Maria Concetta; Damiano, Giuseppe; Altomare, Roberta; Maione, Carolina; Buscemi, Salvatore; Buscemi, Giuseppe; Lo Monte, Attilio Ignazio

    2016-04-01

    Intraoperative parathyroid hormone (PTH) monitoring in the setting of the operating room represents a valuable example of the rationale use of the laboratory diagnostic in a patient-oriented approach. Rapid intraoperative PTH (ioPTH) assay is a valid tool for an accurate evaluation of the success of parathyroid surgery. The reliability of the user-friendly portable systems as well as the collaboration between operators and surgical staff allow the one-site monitoring of the ioPTH decrements on the course of the surgical management of hyperparathyroidism. The rapid answer provided by an effective decrement of PTH during parathyroidectomy contributes dramatically to the efficacy of parathyroid surgery and the reduction of the number of re-operations. Therefore the dose of ioPTH is a valid and reliable support for the success of the intervention of parathyroidectomy at controlled costs. PMID:26708859

  14. Evaluating the effect of intraoperative peritoneal lavage on bacterial culture in dogs with suspected septic peritonitis

    PubMed Central

    Swayne, Seanna L.; Brisson, Brigitte; Weese, J. Scott; Sears, William

    2012-01-01

    This pilot study describes the effect of intraoperative peritoneal lavage (IOPL) on bacterial counts and outcome in clinical cases of septic peritonitis. Intraoperative samples were cultured before and after IOPL. Thirty-three dogs with presumed septic peritonitis on the basis of cytology were managed surgically during the study period. Positive pre-lavage bacterial cultures were found in 14 cases, 13 of which were a result of intestinal leakage. The post-lavage cultures showed fewer isolates in 9 cases and in 1 case became negative. The number of dogs with a decrease in the concentration of bacteria cultured from pre-lavage to post-lavage samples was not statistically significant. There was no significant effect of the change in pre- to post-lavage culture, single versus multiple types of bacteria, selection of an appropriate empiric antimicrobial on survival or the need for subsequent surgery. PMID:23450861

  15. An extraordinary mechanism causing intraoperative migration of the Kirschner-wire.

    PubMed

    Eroğlu, Mehmet; Özcan, Özal; Şentürk, İhsan; Yücehan, Mehmet

    2016-04-01

    Migration of Kirschner wires (K-wires) postoperatively and with use of cannulated implants intraoperatively is a well-known complication. In this article, we present an extraordinary mechanism causing intraoperative migration of a K-wire. A K-wire which was used for temporary fixation of fracture fragments migrated forwardly due to its contact with the drill bit while drilling a hole for a screw. The interaction between the K-wire and the drill bit simulated a gear wheel effect and thus the rotating K-wire advanced. Although no complications occurred in this case, we believe that the mentioned mechanism may be of importance particularly in osteoporotic patients and may cause damage to vital structures. PMID:26874638

  16. [Non-invasive mechanical ventilation in the pre- and intraoperative period and difficult airway].

    PubMed

    Esquinas, A M; Jover, J L; Úbeda, A; Belda, F J

    2015-11-01

    Non-invasive mechanical ventilation is a method of ventilatory assistance aimed at increasing alveolar ventilation, thus achieving, in selected subjects, the avoidance of endotracheal intubation and invasive mechanical ventilation, with the consequent improvement in survival. There has been a systematic review and study of the technical, clinical experiences, and recommendations concerning the application of non-invasive mechanical ventilation in the pre- and intraoperative period. The use of prophylactic non-invasive mechanical ventilation before surgery that involves significant alterations in the ventilatory function may decrease the incidence of postoperative respiratory complications. Its intraoperative use will mainly depend on the type of surgery, type of anaesthetic technique, and the clinical status of the patient. Its use allows greater anaesthetic depth without deterioration of oxygenation and ventilation of patients. PMID:25702198

  17. Novel Intraoperative Technique to Visualize the Lower Cervical Spine: A Case Series.

    PubMed

    Rauck, Ryan; Stammen, Kari; Yu, Elizabeth; Khan, Safdar N

    2016-02-01

    Visualization of the lower cervical spine with a lateral radiograph poses a challenge secondary to encroachment of the shoulders. Applying traction to the arms or taping the shoulders down provides adequate visualization in most patients, but imaging the mid- to lower cervical levels presents a significant challenge in patients with stout necks. We present a variation of the lateral radiograph that is 30º oblique from horizontal and 30º cephalad from neutral and used in a series of patients with stout necks that require anterior instrumentation of the lower cervical spine. We reviewed intraoperative images of 2 patients who underwent anterior cervical spine surgery at our institution, and assessed type of procedure, body mass index, and outcome scores. Our variation provided improved visualization relative to a lateral view and was used intraoperatively to confirm correct-level hardware placement in both patients. PMID:26866322

  18. Global Warming Estimation from MSU

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Iacovazzi, Robert; Yoo, Jung-Moon

    1998-01-01

    Microwave Sounding Unit (MSU) radiometer observations in Ch 2 (53.74 GHz) from sequential, sun-synchronous, polar-orbiting NOAA satellites contain small systematic errors. Some of these errors are time-dependent and some are time-independent. Small errors in Ch 2 data of successive satellites arise from calibration differences. Also, successive NOAA satellites tend to have different Local Equatorial Crossing Times (LECT), which introduce differences in Ch 2 data due to the diurnal cycle. These two sources of systematic error are largely time independent. However, because of atmospheric drag, there can be a drift in the LECT of a given satellite, which introduces time-dependent systematic errors. One of these errors is due to the progressive chance in the diurnal cycle and the other is due to associated chances in instrument heating by the sun. In order to infer global temperature trend from the these MSU data, we have eliminated explicitly the time-independent systematic errors. Both of the time-dependent errors cannot be assessed from each satellite. For this reason, their cumulative effect on the global temperature trend is evaluated implicitly. Christy et al. (1998) (CSL). based on their method of analysis of the MSU Ch 2 data, infer a global temperature cooling trend (-0.046 K per decade) from 1979 to 1997, although their near nadir measurements yield near zero trend (0.003 K/decade). Utilising an independent method of analysis, we infer global temperature warmed by 0.12 +/- 0.06 C per decade from the observations of the MSU Ch 2 during the period 1980 to 1997.

  19. Hot/Warm Gas Cleanup

    SciTech Connect

    Bissett, Larry A.

    2001-11-06

    Using regenerable sorbents and transport or fluid-bed contacting, the Gas Process Development Unit (GPDU) at NETL-Morgantown will be used to demonstrate the process feasibility of removing sulfur from coal gasification or other fuel gas streams at temperatures above dew point of the gas. This technology, also known as hot or warm gas desulfurization, is expected to remove sulfur to concentrations lower than conventional systems at comparable cost. The project was constructed under the U.S. Department of Energy (DOE) Integrated Gasification Combined Cycle (IGCC) power system program and is an ''enabling technology'' in the Vision 21 program. The GPDU was designed to be the smallest scale research and development facility capable of providing viable scale-up design data for new integrated transport or fluid-bed desulfurization processes. With the capability to test at process conditions representative of anticipated commercial applications in terms of temperatures, pressures, major compositions, velocities, and sorbent cycling, the unit is expected to generate important information on process control, configuration, and sorbent suitability. In this way, the GPDU fills a strategic role between past/current small-scale testing and large-scale demonstrations. A primary objective of the project is to gain insight into which reactor combination (i.e., both transport, both fluid bed, or mixed) is more suitable for desulfurization technology and why. Assuming process feasibility is demonstrated, this guides future development or commercial ventures by answering the question of what to build, and provides performance and scale-up data (e.g., required transport reactor densities). Another important objective, which naturally derives from the process development activities, is demonstration of sorbent suitability and readiness for commercial deployment (e.g., sorbent attrition and cycle life). In this sense, the GPDU can serve as a final testing ground to reduce the risks of large-scale sorbent failure.

  20. Delphi Consensus Recommendations: Intraoperative Technique and Postoperative Management of Patients with Natrelle 410 Implants

    PubMed Central

    Brown, Mitchell H.; Hedén, Per; Luan, Jie; Munhoz, Alexandre Mendonça; Carter, Mollie

    2015-01-01

    Background: Anatomically shaped, form-stable Natrelle 410 breast implants were approved in Europe in 1993 and in the United States in 2013. Although general guidelines for breast augmentation are available, the distinctive characteristics of Natrelle 410 warrant specific guidelines for this device. The goal of this study was to generate consensus recommendations for intraoperative technique and postoperative management with Natrelle 410 in primary breast augmentation. Methods: Surgeons were invited to participate in the study, which used a modified Delphi method. Participants completed 2 rounds of online surveys; the second survey (Recommendations Survey) was generated based on first survey results. Respondents also listed top priorities for use of Natrelle 410. Results: Participants (n = 22) reached consensus on 15 of 18 perioperative and surgical techniques; dual-plane placement, tight pockets, and limiting the boundaries of dissection were among intraoperative techniques considered most important for Natrelle 410. Consensus was reached for 18 of 32 items regarding postoperative management and 6 of 9 open-ended postoperative activity restrictions. Consensus on activity restrictions with specified time limits were similar to consensus recommendations on general restrictions. Top participant-identified intraoperative and postoperative management practices for Natrelle 410 were dual-plane placement of the implant and wearing a bra postoperatively, respectively. Conclusions: The Delphi method identified consensus recommendations on a broad range of intraoperative techniques and postoperative management practices for primary breast augmentation with Natrelle 410. These recommendations and priorities provide surgeons with a framework that, together with the surgeon’s experience, will contribute to optimal clinical outcomes with Natrelle 410. PMID:26893982

  1. The impact of feedback of intraoperative technical performance in surgery: a systematic review

    PubMed Central

    Trehan, Abhishek; Barnett-Vanes, Ashton; Carty, Matthew J; McCulloch, Peter; Maruthappu, Mahiben

    2015-01-01

    Objectives Increasing patient demands, costs and emphasis on safety, coupled with reductions in the length of time surgical trainees spend in the operating theatre, necessitate means to improve the efficiency of surgical training. In this respect, feedback based on intraoperative surgical performance may be beneficial. Our aim was to systematically review the impact of intraoperative feedback based on surgical performance. Setting MEDLINE, Embase, PsycINFO, AMED and the Cochrane Database of Systematic Reviews were searched. Two reviewers independently reviewed citations using predetermined inclusion and exclusion criteria. 32 data-points per study were extracted. Participants The search strategy yielded 1531 citations. Three studies were eligible, which comprised a total of 280 procedures by 62 surgeons. Results Overall, feedback based on intraoperative surgical performance was found to be a powerful method for improving performance. In cholecystectomy, feedback led to a reduction in procedure time (p=0.022) and an improvement in economy of movement (p<0.001). In simulated laparoscopic colectomy, feedback led to improvements in instrument path length (p=0.001) and instrument smoothness (p=0.045). Feedback also reduced error scores in cholecystectomy (p=0.003), simulated laparoscopic colectomy (p<0.001) and simulated renal artery angioplasty (p=0.004). In addition, feedback improved balloon placement accuracy (p=0.041), and resulted in a smoother learning curve and earlier plateau in performance in simulated renal artery angioplasty. Conclusions Intraoperative feedback appears to be associated with an improvement in performance, however, there is a paucity of research in this area. Further work is needed in order to establish the long-term benefits of feedback and the optimum means and circumstances of feedback delivery. PMID:26078305

  2. Effects of intraoperative single bolus fentanyl administration and remifentanil infusion on postoperative nausea and vomiting

    PubMed Central

    Lim, Hyungsun; Doo, A Ram; Son, Ji-Seon; Kim, Jin-Wan; Lee, Ki-Jae; Kim, Dong-Chan

    2016-01-01

    Background Although the use of postoperative opioids is a well-known risk factor for postoperative nausea and vomiting (PONV), few studies have been performed on the effects of intraoperative opioids on PONV. We examined the effects of a single bolus administration of fentanyl during anesthesia induction and the intraoperative infusion of remifentanil on PONV. Methods Two hundred and fifty women, aged 20 to 65 years and scheduled for thyroidectomy, were allocated to a control group (Group C), a single bolus administration of fentanyl 2 µg/kg during anesthesia induction (Group F), or 2 ng/ ml of effect-site concentration-controlled intraoperative infusion of remifentanil (Group R) groups. Anesthesia was maintained with sevoflurane and 50% N2O. The incidence and severity of PONV and use of rescue antiemetics were recorded at 2, 6, and 24 h postoperatively. Results Group F showed higher incidences of nausea (60/82, 73% vs. 38/77, 49%; P = 0.008), vomiting (40/82, 49% vs. 23/77 30%; P = 0.041) and the use of rescue antiemetics (47/82, 57% vs. 29/77, 38%; P = 0.044) compared with Group C at postoperative 24 h. However, there were no significant differences in the incidence of PONV between Groups C and R. The overall incidences of PONV for postoperative 24 h were 49%, 73%, and 59% in Groups C, F, and R, respectively (P = 0.008). Conclusions A single bolus administration of fentanyl 2 µg/kg during anesthesia induction increases the incidence of PONV, but intraoperative remifentanil infusion with 2 ng/ml effect-site concentration did not affect the incidence of PONV. PMID:26885302

  3. Negative short-term impact of intraoperative biliary lavage in patients with hepatolithiasis

    PubMed Central

    Jiang, Ou; Zhou, Rong-Xing; Yang, Ke; Cai, Chun-Xian; Liu, Yu; Cheng, Nan-Sheng

    2016-01-01

    AIM: To evaluate short-term outcomes following intraoperative biliary lavage for hepatolithiasis. METHODS: A total of 932 patients who were admitted to the West China Medical Center of Sichuan University between January 2010 and January 2014 and underwent bile duct exploration and lithotomy were retrospectively included in our study. The patients were divided into the lavage group and the control group. Related pre-, intra-, and postoperative factors were recorded, analyzed, and compared between the two groups in order to verify the effects of biliary lavage on the short-term outcome of patients with hepatolithiasis. RESULTS: Amongst the patients who were included, 678 patients with hepatolithiasis were included in the lavage group, and the other 254 patients were enrolled in the control group. Data analyses revealed that preoperative baseline and related intraoperative variables were not significantly different. However, patients who underwent intraoperative biliary lavage had prolonged postoperative hospital stays (6.67 d vs 7.82 d, P = 0.024), higher hospitalization fees (RMB 28437.1 vs RMB 32264.2, P = 0.043), higher positive rates of bacterial cultures from blood (13.3% vs 25.8%, P = 0.001) and bile (23.6% vs 40.7%, P = 0.001) samples, and increased usage of advanced antibiotics (26.3% vs 38.2%, P = 0.001). In addition, in the lavage group, more patients had fever (> 37.5 °C, 81.4% vs 91.1%, P = 0.001) and hyperthermia (> 38.5°C,39.7% vs 54.9%, P = 0.001), and higher white blood cell counts within 7 d after the operation compared to the control group. CONCLUSION: Intraoperative biliary lavage might increase the risk of postoperative infection, while not significantly increasing gallstone removal rate. PMID:27004001

  4. Impact of intraoperative hyperglycaemia on renal dysfunction after off-pump coronary artery bypass

    PubMed Central

    Song, Jong Wook; Shim, Jae Kwang; Yoo, Kyung Jong; Oh, Se Young; Kwak, Young Lan

    2013-01-01

    OBJECTIVES Acute kidney injury (AKI) is one of the most frequently occurring complications after off-pump coronary artery bypass graft (OPCAB). Hyperglycaemia is a major, potentially modifiable risk factor of adverse outcome after cardiac surgery known to aggravate organ damage. The aim of this study was to address the association between intraoperative glucose concentration and postoperative AKI in patients who underwent OPCAB. METHODS The medical records of 880 consecutive patients were retrospectively reviewed. Patients were divided into three groups according to the time-weighted average of intraoperative glucose concentrations (<110, 110–150 and >150 mg/dl), and the incidence of AKI (increase of serum creatinine to >2.0 mg/dl and 2 × most recent preoperative value or a new requirement for dialysis) was compared. Multivariate logistic regression analysis was performed to identify independent risk factors for postoperative AKI. RESULTS The incidence of AKI was higher in patients with a glucose level >150 mg/dl than in patients with a glucose level = 110–150 mg/dl [8% (20 of 251) vs 3% (14 of 453), P = 0.004]. On multivariate analysis, glucose >150 mg/dl (odds ratio [OR], 2.78; 95% confidence interval [CI], 1.12–6.86, P = 0.027), coefficient of variation of glucose (OR, 1.04; 95% CI, 1.01–1.07, P = 0.027) and preoperative serum creatinine >1.4 mg/dl (OR, 8.81; 95% CI, 3.90–19.9, P < 0.001) were identified as independent risk factors for postoperative AKI. CONCLUSIONS Intraoperative glucose concentration >150 mg/dl and increased variability of glucose were independently associated with AKI after OPCAB. Tight intraoperative glycaemic control (<110 mg/dl) does not seem to provide additional benefit in terms of AKI. PMID:23690431

  5. Acute intraoperative brain herniation during elective neurosurgery: pathophysiology and management considerations.

    PubMed Central

    Whittle, I R; Viswanathan, R

    1996-01-01

    OBJECTIVES: To describe operative procedures, pathophysiological events, management strategies, and clinical outcomes after acute intraoperative brain herniation during elective neurosurgery. METHODS: Review of clinical diagnoses, operative events, postoperative CT findings, intracranial pressure, and arterial blood pressure changes and outcomes in a series of patients in whom elective neurosurgery had to be abandoned because of severe brain herniation. RESULTS: Acute intraoperative brain herniation occurred in seven patients. In each patient subarachnoid or intraventricular haemorrhage preceded the brain herniation. The haemorrhage occurred after intraoperative aneurysm rupture either before arachnoidal dissection (three) or during clip placement (one); after resection of 70% of a recurrent hemispheric astroblastoma; after resection of a pineal tumour; and after a stereotactic biopsy of an AIDS lesion. In all patients the procedure was abandoned because of loss of access to the intracranial operating site, medical measures to control intracranial pressure undertaken (intravenous thiopentone), an intraventricular catheter or Camino intracranial pressure monitor inserted, and CT performed immediately after scalp closure. The patients were transferred to an intensive care unit for elective ventilation and multimodality physiological monitoring. Using this strategy all patients recovered from the acute ictus and no patient had intracranial pressure > 35 mm Hg. Although one patient with an aneurysm rebled and died three days later the other six patients did well considering the dramatic and apparently catastrophic nature of the open brain herniation. CONCLUSIONS: There are fundamental differences in the pathophysiological mechanisms, neuroradiological findings, and outcomes between open brain herniation occurring in post-traumatic and elective neurosurgical patients. The surprisingly good outcomes in this series may have occurred because the intraoperative brain herniation was secondary to extra-axial subarachnoid or intraventricular haemorrhage rather than intraparenchymal haemorrhage or acute brain oedema. Expeditious abandonment of the procedure and closure of the cranium may also have contributed to the often very satisfactory clinical outcome. Images PMID:8971104

  6. The importance of intraoperative transoesophageal monitoring when operating on renal cancers that involve the right atrium

    PubMed Central

    Grebenik, K; Patel, N; Cranston, D; Westaby, S

    2014-01-01

    The surgical treatment of advanced renal cancers is challenging. Renal cell carcinoma is interesting in that it invades the vasculature and can extend up as far as the right atrium. Extension of tumour thrombus into the right atrium represents level IV disease, according to Robson staging. Transoesophageal echocardiography is useful for diagnostic purposes. It is also of great value for intraoperative cardiac monitoring and to confirm the extent of vascular involvement. PMID:25198964

  7. Changes in cerebrospinal fluid flow assessed using intraoperative MRI during posterior fossa decompression for Chiari malformation.

    PubMed

    Bond, Aaron E; Jane, John A; Liu, Kenneth C; Oldfield, Edward H

    2015-05-01

    OBJECT The authors completed a prospective, institutional review board-approved study using intraoperative MRI (iMRI) in patients undergoing posterior fossa decompression (PFD) for Chiari I malformation. The purpose of the study was to examine the utility of iMRI in determining when an adequate decompression had been performed. METHODS Patients with symptomatic Chiari I malformations with imaging findings of obstruction of the CSF space at the foramen magnum, with or without syringomyelia, were considered candidates for surgery. All patients underwent complete T1, T2, and cine MRI studies in the supine position preoperatively as a baseline. After the patient was placed prone with the neck flexed in position for surgery, iMRI was performed. The patient then underwent a bone decompression of the foramen magnum and arch of C-1, and the MRI was repeated. If obstruction was still present, then in a stepwise fashion the patient underwent dural splitting, duraplasty, and coagulation of the tonsils, with an iMRI study performed after each step guiding the decision to proceed further. RESULTS Eighteen patients underwent PFD for Chiari I malformations between November 2011 and February 2013; 15 prone preincision iMRIs were performed. Fourteen of these patients (93%) demonstrated significant improvement of CSF flow through the foramen magnum dorsal to the tonsils with positioning only. This improvement was so notable that changes in CSF flow as a result of the bone decompression were difficult to discern. CONCLUSIONS The authors observed significant CSF flow changes when simply positioning the patient for surgery. These results put into question intraoperative flow assessments that suggest adequate decompression by PFD, whether by iMRI or intraoperative ultrasound. The use of intraoperative imaging during PFD for Chiari I malformation, whether by ultrasound or iMRI, is limited by CSF flow dynamics across the foramen magnum that change significantly when the patient is positioned for surgery. PMID:25699415