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Sample records for partial surgery experimental

  1. Partially coherent interferometric biometry in cataract surgery

    NASA Astrophysics Data System (ADS)

    Drexler, Wolfgang; Findl, Oliver; Menapace, Rupert; Hitzenberger, Christoph K.; Fercher, Adolf F.

    1999-02-01

    In an earlier study we showed that precise axial eye length measurement on cataract eyes is possible with the dual beam partial coherence interferometry technique (PCI). A high correlation with the standard ultrasound technique has been obtained. Recently, in a prospective study, partially coherent interferometry and ultrasound biometry were compared in cataract surgery using the SRK II formula based on US applanation biometry. Three months after surgery PCI was repeated and refractive outcome was determined. The use of PCI would have improved refractive outcome by about 30%.

  2. Experimental telemanipulation in endoscopic surgery.

    PubMed

    Schurr, M O; Breitwieser, H; Melzer, A; Kunert, W; Schmitt, M; Voges, U; Buess, G

    1996-06-01

    Today's rigid endoscopic instruments limit the intracorporeal mobility of the surgical tool and are a severe impediment for the further spread of endoscopic techniques in operative medicine. Since 1992 flexible, steerable instruments with additional links for pivoting and rotating the tip have been developed and experimentally evaluated. The latest versions of this series of instruments are equipped with electromotors for better handling. The next aim in this development is a fully mobile telemanipulator with six motion axes dedicated to use in endoscopic surgery. Its first tests are planned for 1995. For successful operation of an electric telemanipulator, the man-machine interface (MMI) is of cardinal importance. For the definition of surgical requirements for the MMI, a conventional master-slave manipulator designed for technical application was modified for use in guiding a laparoscopic instrument. Master and slave sites of the system were 1.3 km apart and linked by means of a fiber-optic cable. Using this modified telepresence system, remote laparoscopic cholecystectomy was feasible in a phantom model. In a standardized test series using a test parcours, different parameters of the control system were modified, and their influence on the execution time of the parcours tasks was recorded. Well-suited parameter configurations were found and allowed experimental verification and completion of the important aspects of our concepts for development of an endoscopic manipulator MMI.

  3. Effect of Timing of Surgery in Partially Injured ACLs.

    PubMed

    Li, Bin; Bai, Lunhao; Fu, Yonghui; Wang, Guangbin; He, Ming; Wang, Jiashi

    2012-05-01

    The purpose of this study was to explore the optimal timing for surgical intervention of partially injured anterior cruciate ligaments (ACL). Thirty-eight patients were divided into early (n=17) or delayed (n=21) surgery groups based on the interval between injury and surgery. Minimum follow-up was 2 years. The outcome measures used were the International Knee Documentation Committee score, Lysholm knee score, Tegner activity rating, range of motion, and arthrometer measurements. The findings of this study indicate that early surgical reconstruction of partially ruptured ACLs did not result in arthrofibrosis but may prevent secondary loosening of the intact bundles and further meniscal and chondral injury.

  4. Experimental generating the partially coherent and partially polarized electromagnetic source.

    PubMed

    Ostrovsky, Andrey S; Rodríguez-Zurita, Gustavo; Meneses-Fabián, Cruz; Olvera-Santamaría, Miguel A; Rickenstorff-Parrao, Carolina

    2010-06-07

    The technique for generating the partially coherent and partially polarized source starting from the completely coherent and completely polarized laser source is proposed and analyzed. This technique differs from the known ones by the simplicity of its physical realization. The efficiency of the proposed technique is illustrated with the results of physical experiment in which an original technique for characterizing the coherence and polarization properties of the generated source is employed.

  5. Cellular proliferation after experimental glaucoma filtration surgery

    SciTech Connect

    Jampel, H.D.; McGuigan, L.J.; Dunkelberger, G.R.; L'Hernault, N.L.; Quigley, H.A.

    1988-01-01

    We used light microscopic autoradiography to determine the time course of cellular incorporation of tritiated thymidine (a correlate of cell division) following glaucoma filtration surgery in seven eyes of four cynomolgus monkeys with experimental glaucoma. Incorporation of tritiated thymidine was detected as early as 24 hours postoperatively. Peak incorporation occurred five days postoperatively and had returned to baseline levels by day 11. Cells incorporating tritiated thymidine included keratocytes, episcleral cells, corneal and capillary endothelial cells, and conjunctival and corneal epithelial cells. Transmission electron microscopy was correlated with the autoradiographic results to demonstrate that fibroblasts were dividing on the corneoscleral margin. These findings have potential clinical implications for the use of antiproliferative agents after filtration surgery.

  6. Diode laser supported partial nephrectomy in laparoscopic surgery: preliminary results

    NASA Astrophysics Data System (ADS)

    Sroka, Ronald; Hennig, Georg; Zillinberg, Katja; Khoder, Wael Y.

    2011-07-01

    Introduction: Warm ischemia and bleeding during laparoscopic partial nephrectomy place technical constraints on surgeons. Therefore it was the aim to develop a safe and effective laser assisted partial nephrectomy technique without need for ischemia. Patients and methods: A diode laser emitting light at 1318nm in cw mode was coupled into a bare fibre (core diameter 600 μm) thus able to transfer up to 100W to the tissue. After dry lab experience, a total of 8 patients suffering from kidney malformations underwent laparoscopic/retroperitoneoscopic partial nephrectomy. Clinically, postoperative renal function and serum c-reactive protein (CRP) were monitored. Laser induced coagulation depth and effects on resection margins were evaluated. Demographic, clinical and follow-up data are presented. Results: Overall interventions, the mean operative time was 116,5 minutes (range 60-175min) with mean blood loss of 238ml (range 50-600ml) while laser assisted resection of the kidney tissue took max 15min. After extirpation of the tumours all patients showed clinical favourable outcome during follow up period. The tumour size was measured to be 1.8 to 5cm. With respect to clinical safety and due to blood loos, two warm ischemia (19 and 24min) must be performed. Immediate postoperative serum creatinine and CRP were elevated within 0.1 to 0.6 mg/dl (mean 0.18 mg/dl) and 2.1-10 mg/dl (mean 6.24 mg/dl), respectively. The depth of the coagulation on the removed tissue ranged between <1 to 2mm without effect on histopathological evaluation of tumours or resection margin. As the surface of the remaining kidney surface was laser assisted coagulated after removal. The sealing of the surface was induced by a slightly larger coagulation margin, but could not measured so far. Conclusion: This prospective in-vivo feasibility study shows that 1318nm-diode laser assisted partial nephrectomy seems to be a safe and promising medical technique which could be provided either during open surgery

  7. Aqueous humor changes after experimental filtering surgery.

    PubMed

    Radius, R L; Herschler, J; Claflin, A; Fiorentino, G

    1980-02-01

    We studied aqueous humor of rhesus and owl monkeys for its effect on the growth of subconjunctival fibroblasts in tissue culture. Aqueous humor samples obtained before glaucoma surgery inhibited the initiation of growth of fibroblasts. However, postoperative aqueous humor samples supported growth of fibroblasts. The change in aqueous humor physiology lasted for up to two months after glaucoma surgery. Our study indicated that possibly material added to the postoperative aqueous humor inactivates an inhibitor normally present in primary aqueous humor. An alternative explanation would be that primary aqueous humor, in contrast to secondary aqueous humor, lacks sufficient nutrient material to support fibroblast growth in tissue culture.

  8. Nonrigid liver registration for image-guided surgery using partial surface data: a novel iterative approach

    NASA Astrophysics Data System (ADS)

    Rucker, D. Caleb; Wu, Yifei; Ondrake, Janet E.; Pheiffer, Thomas S.; Simpson, Amber L.; Miga, Michael I.

    2013-03-01

    In the context of open abdominal image-guided liver surgery, the efficacy of an image-guidance system relies on its ability to (1) accurately depict tool locations with respect to the anatomy, and (2) maintain the work flow of the surgical team. Laser-range scanned (LRS) partial surface measurements can be taken intraoperatively with relatively little impact on the surgical work flow, as opposed to other intraoperative imaging modalities. Previous research has demonstrated that this kind of partial surface data may be (1) used to drive a rigid registration of the preoperative CT image volume to intraoperative patient space, and (2) extrapolated and combined with a tissue-mechanics-based organ model to drive a non-rigid registration, thus compensating for organ deformations. In this paper we present a novel approach for intraoperative nonrigid liver registration which iteratively reconstructs a displacement field on the posterior side of the organ in order to minimize the error between the deformed model and the intraopreative surface data. Experimental results with a phantom liver undergoing large deformations demonstrate that this method achieves target registration errors (TRE) with a mean of 4.0 mm in the prediction of a set of 58 locations inside the phantom, which represents a 50% improvement over rigid registration alone, and a 44% improvement over the prior non-iterative single-solve method of extrapolating boundary conditions via a surface Laplacian.

  9. Partial ACL tears: anatomic reconstruction versus nonanatomic augmentation surgery.

    PubMed

    Buda, Roberto; Ruffilli, Alberto; Parma, Alessandro; Pagliazzi, Gherardo; Luciani, Deianira; Ramponi, Laura; Castagnini, Francesco; Giannini, Sandro

    2013-09-01

    Treatment of partial anterior cruciate ligament (ACL) tears requires ACL remnant preservation. The goal of this study was to compare the outcome of anatomic reconstruction of the torn bundle with nonanatomic augmentation using the over-the-top femoral route. Fifty-two athletes (mean age, 23.3 years) with partial ACL lesions underwent anatomic reconstruction (n=26) or nonanatomic augmentation (n=26). Intraoperative damage of the healthy bundle that required a standard ACL reconstruction occurred in 2 patients in the anatomic reconstruction group. International Knee Documentation Committee (IKDC) score, Tegner score, and arthrometer evaluation were used pre-operatively and at follow-up for up to 5 years postoperatively. One failure occurred in the anatomic reconstruction group. Mean IKDC subjective score at follow-up was 88.2 ± 5.7 in the anatomic reconstruction group and 90.2 ± 4.7 in the nonanatomic augmentation group. According to the IKDC objective score at final follow-up, 96% of knees in the nonanatomic augmentation group were normal vs 87.5% in the anatomic reconstruction group. No significative differences were observed between the 2 groups at final follow-up. Anteromedial bundle reconstruction showed significantly lower IKDC subjective and objective scores and higher residual instability values as evaluated with the arthrometer compared with posterolateral bundle reconstruction (P=.017). The surgical treatment of ACL partial tears is demanding. Adapted portals, perfect control of the tunnel drilling process, and intercondylar space management are required in anatomic reconstruction. The nonanatomic augmentation technique is simpler, providing excellent durable results over time with a lower complication rate. Anteromedial bundle reconstruction is associated with a poorer outcome, especially when performed with anatomic reconstruction.

  10. Robotic surgery and hemostatic agents in partial nephrectomy: a high rate of success without vascular clamping.

    PubMed

    Morelli, Luca; Morelli, John; Palmeri, Matteo; D'Isidoro, Cristiano; Kauffmann, Emanuele Federico; Tartaglia, Dario; Caprili, Giovanni; Pisano, Roberta; Guadagni, Simone; Di Franco, Gregorio; Di Candio, Giulio; Mosca, Franco

    2015-09-01

    Robot-assisted partial nephrectomy has been proposed as a technique to overcome technical challenges of laparoscopic partial nephrectomy. We prospectively collected and analyzed data from 31 patients who underwent robotic partial nephrectomy with systematic use of hemostatic agents, between February 2009 and October 2014. Thirty-three renal tumors were treated in 31 patients. There were no conversions to open surgery, intraoperative complications, or blood transfusions. The mean size of the resected tumors was 27 mm (median 20 mm, range 5-40 mm). Twenty-seven of 33 lesions (82%) did not require vascular clamping and therefore were treated in the absence of ischemia. All margins were negative. The high partial nephrectomy success rate without vascular clamping suggests that robotic nephron-sparing surgery with systematic use of hemostatic agents may be a safe, effective method to completely avoid ischemia in the treatment of selected renal masses.

  11. Adrenal-preserving minimally invasive surgery: update on the current status of laparoscopic partial adrenalectomy.

    PubMed

    Disick, Grant I S; Munver, Ravi

    2008-01-01

    Adrenalectomy is the standard of care for hormonally active adrenal masses. In recent years, minimally invasive laparoscopic excision has become a preferred management option. As with advances in parenchymal-sparing renal surgery, investigators have begun to examine adrenal-sparing procedures to preserve functional adrenal tissue. This article reviews the recent literature and reports on intermediate results with laparoscopic partial adrenalectomy (LPA).

  12. [The current role of partial surgery as a strategy for functional preservation in laryngeal carcinoma].

    PubMed

    Rodrigo, Juan Pablo; Coca-Pelaz, Andrés; Suárez, Carlos

    2011-01-01

    With the current advances and recent organ preservation protocols for intermediate or advanced stage laryngeal cancer, based on chemotherapy, the role of surgery seemed replaced except for surgical rescue of tumours not responding to these treatments, total laryngectomy being the surgical option. This type of non-surgical treatment is offered as a strategy for organ preservation, as opposed to total laryngectomy. However, we believe that there are two organ-preservation strategies, surgical and non-surgical. A wide spectrum of surgical techniques is available and such techniques lead to excellent results, both oncological and functional (speech and swallowing). The aim of this paper is to present options for organ-preserving surgery for laryngeal cancer. A review of surgical techniques available for functional preservation in cancer of the larynx at intermediate or advanced stage is presented. In addition to classic approaches such as vertical partial laryngectomy and horizontal or supraglottic laryngectomy, options for conservative laryngeal surgery have improved significantly over the past two decades. Minimally invasive surgery, transoral laser surgery, and supracricoid partial laryngectomy have become important laryngeal preservation approaches for patients with laryngeal cancer. Surgery must define its role in the multidisciplinary treatment of advanced cancers of the larynx, which at present often favours (chemo)radiotherapy protocols.

  13. Partial discharge in a high voltage experimental test assembly

    SciTech Connect

    Koss, R.J.; Brainard, J.P.

    1998-07-01

    This study was initiated when a new type of breakdown occurred in a high voltage experimental test assembly. An anomalous current pulse was observed, which indicated partial discharges, some leading to total breakdowns. High voltage insulator defects are shown along with their effect on the electrostatic fields in the breakdown region. OPERA electromagnetic field modeling software is used to calculate the fields and present a cause for the discharge. Several design modifications are investigated and one of the simplest resulted in a 25% decrease in the field at the discharge surface.

  14. Partial podocyte replenishment in experimental FSGS derives from nonpodocyte sources.

    PubMed

    Kaverina, Natalya V; Eng, Diana G; Schneider, Remington R S; Pippin, Jeffrey W; Shankland, Stuart J

    2016-06-01

    The current studies used genetic fate mapping to prove that adult podocytes can be partially replenished following depletion. Inducible NPHS2-rtTA/tetO-Cre/RS-ZsGreen-R reporter mice were generated to permanently label podocytes with the ZsGreen reporter. Experimental focal segmental glomerulosclerosis (FSGS) was induced with a cytotoxic podocyte antibody. On FSGS day 7, immunostaining for the podocyte markers p57, synaptopodin, and podocin were markedly decreased by 44%, and this was accompanied by a decrease in ZsGreen fluorescence. The nuclear stain DAPI was absent in segments of reduced ZsGreen and podocyte marker staining, which is consistent with podocyte depletion. Staining for p57, synaptopodin, podocin, and DAPI increased at FSGS day 28 and was augmented by the ACE inhibitor enalapril, which is consistent with a partial replenishment of podocytes. In contrast, ZsGreen fluorescence did not return and remained significantly low at day 28, indicating replenishment was from a nonpodocyte origin. Despite administration of bromodeoxyuridine (BrdU) thrice weekly throughout the course of disease, BrdU staining was not detected in podocytes, which is consistent with an absence of proliferation. Although ZsGreen reporting was reduced in the tuft at FSGS day 28, labeled podocytes were detected along the Bowman's capsule in a subset of glomeruli, which is consistent with migration from the tuft. Moreover, more than half of the migrated podocytes coexpressed the parietal epithelial cell (PEC) proteins claudin-1, SSeCKS, and PAX8. These results show that although podocytes can be partially replenished following abrupt depletion, a process augmented by ACE inhibition, the source or sources are nonpodocyte in origin and are independent of proliferation. Furthermore, a subset of podocytes migrate to the Bowman's capsule and begin to coexpress PEC markers.

  15. [Submucosal Partial-turbinectomy (SPT) Preceding an Endoscopic Sinus Surgery (ESS) Procedure].

    PubMed

    Hirai, Tomohisa; Fukushima, Noriyuki; Miyahara, Nobuyuki; Miyoshi, Ayako; Ariki, Masahiko

    2015-07-01

    Preceding a endoscopic sinus surgery (ESS), we have proposed performing a submucosal partial-turbinectomy (SPT) which removes a part of the inferior nasal concha bone attached to maxillary sinus with an antrostomy. By this method, we could not only make a large antrostomy but also obtain good maneuverability by opening the middle nasal meatus in ESS. We performed SPT preceding ESS in 140 cases (261 sides) between January 2012 and June 2014. The stenosis rates of the middle nasal meatus were 14.2% (37 sides from 261 sides) in one month, 7.4% (18 sides from 243 sides) in three months and 3.7% (6 sides from 163 sides) in 6 months after surgery. The closing rates of the antrostomy were 1.5% (4 sides from 261 sides) in one month, 2.9% (7 sides from 243 sides) in three months and 6.7% (11 sides from 163 sides) in 6 months after surgery. We considered that the SPT method would contribute to secure sufficient ventilation routes for wound healing of sinusitis following surgery on the mucous membrane. In addition, the SPT method has merit from the point of deceasing risks of atrophic rhinitis and empty nose syndrome by preserving most of the inferior nasal concha.

  16. Pseudoepitheliomatous hyperplasia after diode laser oral surgery. An experimental study

    PubMed Central

    Seoane, Juan; González-Mosquera, Antonio; García-Martín, José-Manuel; García-Caballero, Lucía; Varela-Centelles, Pablo

    2015-01-01

    Background To examine the process of epithelial reparation in a surgical wound caused by diode laser. Material and Methods An experimental study with 27 Sprage-Dawley rats was undertaken. The animals were randomly allocated to two experimental groups, whose individuals underwent glossectomy by means of a diode laser at different wattages, and a control group treated using a number 15 scalpel blade. The animals were slaughtered at the 2nd, 7th, and 14th day after glossectomy. The specimens were independently studied by two pathologists (blinded for the specimens’ group). Results At the 7th day, re-epithelisation was slightly faster for the control group (conventional scalpel) (p=0.011). At the 14th day, complete re-epithelization was observed for all groups. The experimental groups displayed a pseudoepitheliomatous hyperplasia. Conclusions It is concluded that, considering the limitations of this kind of experimental studies, early re-epithelisation occurs slightly faster when a conventional scalpel is used for incision, although re-epithelisation is completed in two weeks no matter the instrument used. In addition, pseudoepitheliomatous hyperplasia is a potential event after oral mucosa surgery with diode laser. Knowledge about this phenomenon (not previously described) may prevent diagnostic mistakes and inadequate treatment approaches, particularly when dealing with potentially malignant oral lesions. Key words:Diode laser, animal model, oral biopsy, oral cancer, oral precancer, pseudoepitheliomatous hyperplasia. PMID:26116841

  17. Survival benefit of partial nephrectomy: Reconciling experimental and observational data.

    PubMed

    Tan, Hung-Jui

    2015-12-01

    Given recent epidemiological and practice trends, small kidney cancers are poised to become a focus of modern-day surgical care provided by urologists and urologic oncologists. For the past decade, partial nephrectomy has been viewed as preferable to radical nephrectomy for the treatment of many patients with early-stage kidney cancer, partly because observational studies suggest a survival benefit with nephron sparing. More recently, European Organisation for Research and Treatment of Cancer 30904--a phase 3 randomized control trial--demonstrated better survival for patients treated with radical vs. partial nephrectomy. Shortly thereafter, an instrumental variable analysis reported a survival advantage with partial nephrectomy. Although seemingly contradictory, these studies are potentially reconcilable when considering methodological differences and other empiric work.

  18. Long-Term Changes in Refractive Error and Clinical Evaluation in Partially Accommodative Esotropia after Surgery

    PubMed Central

    Oh, Shin Yeop; Lee, Ju-Yeun; Park, Kyung-Ah; Oh, Sei Yeul

    2016-01-01

    We investigate the changes in refractive error and clinical evaluation in partially accommodative esotropia(PAET) after surgery. A total of 68 patients PAET who received at least 2 years of follow-up after surgery were enrolled in this study. We performed a retrospective study in patients who underwent unilateral or bilateral medial rectus recession for a non-accommodative component of PAET between January 2005 and March 2013. Patients were divided into groups according to the presence of dominancy (dominant, non-dominant, alternative eye), and presence of amblyopia (amblyopic, fellow, normal eye). Changes and changing pattern in SE refractive error were analyzed in all patients and compared between groups. Patients were divided into two groups, those weaned off of hyperopic glasses and those who continued using them, then factors that significantly influenced the continued use of glasses were analyzed. The changes and changing pattern in SE refractive error according to time after operation and presence of amblyopia or dominancy. The mean length of follow-up was 4.89±1.74 years after surgery and the mean change in SE refractive error rate per year was -0.284±0.411 diopters (D). The pattern of changes in the mean SE refractive error for those with dominant, non-dominant, and alternative eyes was not significantly different (p = 0.292). The pattern of changes in the mean SE refractive error for those with amblyopic, fellow, and normal eyes was significantly different (p = 0.0002). Patients were successfully weaned off of hyperopic glasses at an average age of 9.41±2.74 years. The average SE refractive error in the group weaned off of hyperopic glasses was significantly lower than that in the group maintained on hyperopic glasses (p = 0.0002). The change of SE refractive error in amblyopic eyes decreased less than that in fellow or normal eyes, which may be correlated with the presence of amblyopia. Patients with a smaller esodeviated angle without hyperopic

  19. Numerical and Experimental Study on Unsteady Shedding of Partial Cavitation

    NASA Astrophysics Data System (ADS)

    Ji, Bin; Luo, Xianwu; Wu, Yulin; Peng, Xiaoxing; Xu, Hongyuan

    Periodically unsteady shedding of partial cavity and forming of cavitation cloud have a great influence on hydraulic performances and cavitation erosion for ship propellers and hydro machines. In the present study, the unsteady cavitating flow around a hydrofoil has been calculated by using the single fluid approach with a developed cavitation mass transfer expression based on the vaporization and condensation of the fluid. The numerical simulation depicted the unsteady shedding of partial cavity, such as the process of cavity developing, breaking off and collapsing in the downstream under the steady incoming flow condition. It is noted that good agreement between the numerical results and that of experiment conducted at a cavitation tunnel is achieved. The cavitating flow field indicates that the cavity shedding was mainly caused by the re-entrant jet near cavity trailing edge, which was also clearly recorded by high-speed photographing.

  20. Experimental evidence supports mantle partial melting in the asthenosphere.

    PubMed

    Chantel, Julien; Manthilake, Geeth; Andrault, Denis; Novella, Davide; Yu, Tony; Wang, Yanbin

    2016-05-01

    The low-velocity zone (LVZ) is a persistent seismic feature in a broad range of geological contexts. It coincides in depth with the asthenosphere, a mantle region of lowered viscosity that may be essential to enabling plate motions. The LVZ has been proposed to originate from either partial melting or a change in the rheological properties of solid mantle minerals. The two scenarios imply drastically distinct physical and geochemical states, leading to fundamentally different conclusions on the dynamics of plate tectonics. We report in situ ultrasonic velocity measurements on a series of partially molten samples, composed of mixtures of olivine plus 0.1 to 4.0 volume % of basalt, under conditions relevant to the LVZ. Our measurements provide direct compressional (V P) and shear (V S) wave velocities and constrain attenuation as a function of melt fraction. Mantle partial melting appears to be a viable origin for the LVZ, for melt fractions as low as ~0.2%. In contrast, the presence of volatile elements appears necessary to explaining the extremely high V P/V S values observed in some local areas. The presence of melt in LVZ could play a major role in the dynamics of plate tectonics, favoring the decoupling of the plate relative to the asthenosphere.

  1. Experimental evidence supports mantle partial melting in the asthenosphere

    PubMed Central

    Chantel, Julien; Manthilake, Geeth; Andrault, Denis; Novella, Davide; Yu, Tony; Wang, Yanbin

    2016-01-01

    The low-velocity zone (LVZ) is a persistent seismic feature in a broad range of geological contexts. It coincides in depth with the asthenosphere, a mantle region of lowered viscosity that may be essential to enabling plate motions. The LVZ has been proposed to originate from either partial melting or a change in the rheological properties of solid mantle minerals. The two scenarios imply drastically distinct physical and geochemical states, leading to fundamentally different conclusions on the dynamics of plate tectonics. We report in situ ultrasonic velocity measurements on a series of partially molten samples, composed of mixtures of olivine plus 0.1 to 4.0 volume % of basalt, under conditions relevant to the LVZ. Our measurements provide direct compressional (VP) and shear (VS) wave velocities and constrain attenuation as a function of melt fraction. Mantle partial melting appears to be a viable origin for the LVZ, for melt fractions as low as ~0.2%. In contrast, the presence of volatile elements appears necessary to explaining the extremely high VP/VS values observed in some local areas. The presence of melt in LVZ could play a major role in the dynamics of plate tectonics, favoring the decoupling of the plate relative to the asthenosphere. PMID:27386548

  2. Experimentally superposing two pure states with partial prior knowledge

    NASA Astrophysics Data System (ADS)

    Li, Keren; Long, Guofei; Katiyar, Hemant; Xin, Tao; Feng, Guanru; Lu, Dawei; Laflamme, Raymond

    2017-02-01

    Superposition, arguably the most fundamental property of quantum mechanics, lies at the heart of quantum information science. However, how to create the superposition of any two unknown pure states remains as a daunting challenge. Recently, it was proved that such a quantum protocol does not exist if the two input states are completely unknown, whereas a probabilistic protocol is still available with some prior knowledge about the input states [M. Oszmaniec et al., Phys. Rev. Lett. 116, 110403 (2016), 10.1103/PhysRevLett.116.110403]. The knowledge is that both of the two input states have nonzero overlaps with some given referential state. In this work, we experimentally realize the probabilistic protocol of superposing two pure states in a three-qubit nuclear magnetic resonance system. We demonstrate the feasibility of the protocol by preparing a families of input states, and the average fidelity between the prepared state and expected superposition state is over 99%. Moreover, we experimentally illustrate the limitation of the protocol that it is likely to fail or yields very low fidelity, if the nonzero overlaps are approaching zero. Our experimental implementation can be extended to more complex situations and other quantum systems.

  3. Partial reanimation of experimental complex ANI at Mt. Aragats (proposal)

    NASA Astrophysics Data System (ADS)

    Shaulov, S.B.; Martirosov, R.M.; Mamidjanian, E.A.; Jones, L.W.; Saavedra, O.; Tamada, M.

    We present the proposal for reanimation of the half-built experimental complex ANI at Mt. Aragats (Armenia, 3200 m a.s.l.). It is proposed as a first stage to complete the functioning GAMMA installation by big X-ray emulsion chamber for detailed study of EAS cores at energies 1-100 PeV. Preliminary data obtained in this fieled by the Tien Shan “Hadron” installation are presented. This proposal is an EFT and requests creation of an international cooperation.

  4. Partial reanimation of experimental complex ANI at Mt. Aragats (proposal)

    NASA Astrophysics Data System (ADS)

    Shaulov, S. B.; Martirosov, R. M.; Mamidjanian, E. A.; Jones, L. W.; Saavedra, O.; Tamada, M.

    2009-12-01

    The proposal is presented for reanimation of the half-built experimental complex ANI at Mt. Aragats (Armenia, 3200 m a.s.l.). It is proposed as a first stage to complete the functioning GAMMA installation by big X-ray emulsion chamber for detailed study of extensive air shower cores at energies 1-100 PeV. Preliminary data obtained in this field by the Tien-Shan HADRON installation are presented. This proposal is an EFT and requests creation of an international cooperation.

  5. Experimental study of seismic attenuation in partially saturated porous media

    NASA Astrophysics Data System (ADS)

    Barrière, Julien; Bordes, Clarisse; Sénéchal, Pascale

    2010-05-01

    Nowadays, it is well admitted that hydrogeological properties of the porous media (porosity, fluid saturation and permeability) can influence seismic properties. In geophysics, the major theory which links hydrogeological and seismic parameters is poroelasticity proposed by Biot (1956). The Biot relaxation process is due to the relative displacement of fluid in comparison to the solid which causes a significant attenuation of seismic waves, notably in unconsolidated medium. In partially saturated medium, pore fluids are considered as a perfect mixture and so called 'effective fluid'. However, in more consolidated rocks, the Biot theory is not sufficient to explain the attenuation level as measured from field seismic and sonic log data. In the last decade, some authors provide new theories to understand the attenuation caused by the interaction of the different fluids. Most experiments are done in the ultrasonic frequency range, where sources of attenuation (like scattering or local fluid flow) are different as in the low frequency range where the wavelength is greater than heterogeneities size. In this way, we propose a forward-looking experiment with the use of a vertical impulsionnal seismic source which have a strong amplitude spectrum ranging from 100Hz to 8kHz. We study three different unconsolidated porous media at atmospheric pressure: fine-grained sand, coarsed-grained sand and coarse gravel. Water content is measured with a calibrated capacitance probe and temperature effects are corrected. Seismic wave propagation is recorded by piezoelectric accelerometers designed for frequencies below 10kHz. The water injection is done by imbibition. We propose to analyse the attenuation in the [100Hz-1.5kHz] frequency range for the studied media with various water saturation levels. The attenuation varies according to the porous medium and the water content and appears more significant at dry condition and at high saturation level. The weak cohesion at dry condition

  6. The Relationship Between Oxygen Reserve Index and Arterial Partial Pressure of Oxygen During Surgery

    PubMed Central

    Dorotta, Ihab L.; Wells, Briana; Juma, David; Applegate, Patricia M.

    2016-01-01

    BACKGROUND: The use of intraoperative pulse oximetry (Spo2) enhances hypoxia detection and is associated with fewer perioperative hypoxic events. However, Spo2 may be reported as 98% when arterial partial pressure of oxygen (Pao2) is as low as 70 mm Hg. Therefore, Spo2 may not provide advance warning of falling arterial oxygenation until Pao2 approaches this level. Multiwave pulse co-oximetry can provide a calculated oxygen reserve index (ORI) that may add to information from pulse oximetry when Spo2 is >98%. This study evaluates the ORI to Pao2 relationship during surgery. METHODS: We studied patients undergoing scheduled surgery in which arterial catheterization and intraoperative arterial blood gas analysis were planned. Data from multiple pulse co-oximetry sensors on each patient were continuously collected and stored on a research computer. Regression analysis was used to compare ORI with Pao2 obtained from each arterial blood gas measurement and changes in ORI with changes in Pao2 from sequential measurements. Linear mixed-effects regression models for repeated measures were then used to account for within-subject correlation across the repeatedly measured Pao2 and ORI and for the unequal time intervals of Pao2 determination over elapsed surgical time. Regression plots were inspected for ORI values corresponding to Pao2 of 100 and 150 mm Hg. ORI and Pao2 were compared using mixed-effects models with a subject-specific random intercept. RESULTS: ORI values and Pao2 measurements were obtained from intraoperative data collected from 106 patients. Regression analysis showed that the ORI to Pao2 relationship was stronger for Pao2 to 240 mm Hg (r2 = 0.536) than for Pao2 over 240 mm Hg (r2 = 0.0016). Measured Pao2 was ≥100 mm Hg for all ORI over 0.24. Measured Pao2 was ≥150 mm Hg in 96.6% of samples when ORI was over 0.55. A random intercept variance component linear mixed-effects model for repeated measures indicated that Pao2 was significantly related to ORI

  7. Thermo-magnetic surgery for experimental renal cancer.

    PubMed

    Rand, R W; Snow, H D; Elliott, D G; Bubbers, J E; Barbaric, Z L; Brown, W J

    1982-09-01

    Thermo-magnetic surgery is an innovative modality in the treatment of malignancies. This unique combination can produce selectively controlled destruction of deep tumors. Heating of the magnetic metallic compounds of ferrosilicone by hysteresis produces temperatures which are incompatible with cancer cell survival. The intense focal heating causes a coagulation necrosis. Damage to surrounding normal tissue can be avoided by careful temperature monitoring and power control of the magnetic field. Cell destruction in the target tissue has been demonstrated by light and electron microscopy. Reproducible and predictable VX2 renal carcinomas in rabbits have been produced and used as the tumor model in the initial experiments of this research project. A clinical trial with selected cancer patients, performed with this technique of thermo-magnetic surgery, is now a reasonable and feasible procedure.

  8. Partial nephrectomy using radiofrequency incremental bipolar generator with multi electrode probe: experimental study in bench pig kidneys

    PubMed Central

    2014-01-01

    Background The aim of this research project was the realization of an incremental bipolar radiofrequency generator with inline 4-electrode probe for partial renal resection without clamping of the vessels. Methods The experimentation was carried out across two phases: the preliminary realization of a specific generator and an inline multielectrode probe for open surgery (Phase 1); system testing on 27 bench kidneys for a total of 47 partial resection (Phase 2). The parameters evaluated were: power level, generator automatisms, parenchymal coagulation times, needle caliber, thickness of the coagulated tissue “slice”, charring, ergonomy, feasibility of the application of “bolster” stitches. Results The analysis of the results referred to the homogeneity and thickness of coagulation, energy supply times with reference to the power level and caliber of the needles. The optimal results were obtained by using needles of 1.5 mm caliber at power level 5, and with coagulation times of 54 seconds for the first insertion and 30 seconds for the second. Conclusions The experimentation demonstrated that the apparatus, consisting of a generator named “LaparoNewPro” and fitted with a dedicated probe for open surgery, is able to carry out a coagulation of the line of resection of the renal parenchyma in a homogeneous manner, in short times, without tissue charring, and with the possibility of stitching both on coagulated tissue and the caliceal system. The generator automatism based on the flow of the current supplied by each electrode is reliable, and the cessation of energy supply coincides with optimal coagulation. PMID:24410789

  9. Experimental realization of optimal asymmetric cloning and telecloning via partial teleportation.

    PubMed

    Zhao, Zhi; Zhang, An-Ning; Zhou, Xiao-Qi; Chen, Yu-Ao; Lu, Chao-Yang; Karlsson, Anders; Pan, Jian-Wei

    2005-07-15

    We report an experimental realization of both optimal asymmetric cloning and telecloning of single photons by making use of partial teleportation of an unknown state. In the experiment, we demonstrate that, conditioned on the success of partial teleportation of single photons, not only the optimal asymmetric cloning can be accomplished, but also one of two outputs can be transferred to a distant location, realizing the telecloning. The experimental results represent a novel way to achieve quantum cloning and may have potential applications in the context of quantum communication.

  10. Adrenal-preserving minimally invasive surgery: the role of laparoscopic partial adrenalectomy, cryosurgery, and radiofrequency ablation of the adrenal gland.

    PubMed

    Munver, Ravi; Del Pizzo, Joseph J; Sosa, R Ernest

    2003-02-01

    Adrenalectomy has become the standard of care for the management of hormonally active adrenal masses. Various surgical therapies have been proposed to excise completely or destroy these adrenal lesions, which may be benign or malignant. New minimally invasive, adrenal-sparing procedures have recently been introduced, among them laparoscopic partial adrenalectomy, cryosurgery, and radiofrequency ablation. These procedures focus on reducing patient morbidity and hastening postoperative recovery while preserving normal adrenal tissue. However, questions remain about the risks and benefits associated with routine application of minimally invasive therapies for adrenal-sparing surgery in terms of complete tumor extirpation. Clearly, more experience and longer follow-up is necessary to validate these procedures. Herein we describe the surgical techniques and early results of treatment with adrenal-sparing surgery.

  11. Partial hepatectomy hemodynamics changes: Experimental data explained by closed-loop lumped modeling.

    PubMed

    Audebert, Chloe; Bekheit, Mohamed; Bucur, Petru; Vibert, Eric; Vignon-Clementel, Irene E

    2017-01-04

    The liver function may be degraded after partial liver ablation surgery. Adverse liver hemodynamics have been shown to be associated to liver failure. The link between these hemodynamics changes and ablation size is however poorly understood. This article proposes to explain with a closed-loop lumped model the hemodynamics changes observed during twelve surgeries in pigs. The portal venous tree is modeled with a pressure-dependent variable resistor. The variables measured, before liver ablation, are used to tune the model parameters. Then, the liver partial ablation is simulated with the model and the simulated pressures and flows are compared with post-operative measurements. Fluid infusion and blood losses occur during the surgery. The closed-loop model presented accounts for these blood volume changes. Moreover, the impact of blood volume changes and the liver lobe mass estimations on the simulated variables is studied. The typical increase of portal pressure, increase of liver pressure loss, slight decrease of portal flow and major decrease in arterial flow are quantitatively captured by the model for a 75% hepatectomy. It appears that the 75% decrease in hepatic arterial flow can be explained by the resistance increase induced by the surgery, and that no hepatic arterial buffer response (HABR) mechanism is needed to account for this change. The different post-operative states, observed in experiments, are reproduced with the proposed model. Thus, an explanation for inter-subjects post-operative variability is proposed. The presented framework can easily be adapted to other species circulations and to different pathologies for clinical hepatic applications.

  12. Experimental evaluation of water-jet dissection in endoscopic surgery.

    PubMed

    Cuschieri, A

    1994-01-01

    The problems associated with high-velocity high-pressure water-jet dissection were investigated by in-vivo experiments using endoscopic equipment. Three problems were identified: backspray with fouling of the optic, poor control of the depth of cut, and detachment of tissue fragments and isolated cells which contaminate the operative field. The first two problems have been resolved by adoption of a hooded hand-piece and the incorporation of an adjustable back stop. A "dry" system which enables the evacuation of the back spray may deal with the problem of contamination of the operative field by detached cells but further in-vivo experiments are needed to confirm this. Until then, water-jet cutting is considered unsafe for both open and endoscopic surgery in patients undergoing extirpative procedures for cancer because of the risk of tumour seeding within the peritoneal cavity.

  13. [The experimental surgery and your relation with the university: an experience report].

    PubMed

    Yamaki, Vitor Nagai; Teixeira, Renan Kleber Costa; Feijo, Daniel Haber; Silva, José Antonio Cordero da; Botelho, Nara Macedo; Henriques, Marcus Vinicius

    2014-01-01

    The laboratory of experimental surgery represents one of the key points for the university, especially in the biomedical area. This focuses on the university's tripod of primary structure that are teaching, research and extension, which are essential for formation of humanistic and practice of a good doctor that is based, first of all, on scientific evidence and critical knowledge. The importance of a laboratory of experimental surgery centers for medical education was regulated from the new curriculum guidelines of the Ministério da Educação e Cultura, establishing a mandatory laboratory within college centers. Therefore, it is of great importance to the contribution of the laboratories of experimental surgery in the curriculum, both in the discipline of surgical technics and experimental surgery, and an incentive for basic research. Thus, the study presents the experience of 15 years of the Laboratory of Experimental Surgery from Universidade do Estado do Pará, with the goal show the importance of this to medical graduation and the university.

  14. Biomechanical testing in experimental surgery by laser holography

    NASA Astrophysics Data System (ADS)

    Podbielska, Halina; Kasprzak, Henryk T.; Pennig, Dietmar

    1990-06-01

    Of all the capabilities of holography for image processing and measuring purposes, holographic interferometry has found the broadest application in biological and medical research. As a technique, which is non-destructive and allows for high resolving deformation analysis, holographic interferometry has gained popularity over the recent years in experimental biomechanics and orthopaedics. Some examples of holographic interferometry in experimental orthopaedics are reviewed in this report. The possibility of using holographic interferometry to study the behaviour of broken bones supported by fixing devices is pointed out in this review.

  15. Intraoperative Electrophysiologic Monitoring of Ocular Motor Nerves Under Conditions of Partial Neuromuscular Blockade During Skull Base Surgery

    PubMed Central

    Kawaguchi, Masahiko; Ohnishi, Hideyuki; Sakamoto, Takanori; Shimizu, Kiyoshi; Karasawa, Jun; Furuya, Hitoshi

    1996-01-01

    The feasibility and usefulness of intraoperative electromyographic monitoring of the oculomotor nerve (CN III), trochlear nerve (CN IV), and abducens nerve (CN IV) were evaluated under conditions of partial neuromuscular blockade in 21 patients undergoing skill base surgery. Intracranial electrical stimulation of each nerve was performed, and compound muscle action potentials (CMAPs) were reconded from the inferior or superior rectus muscle, the superior oblique muscle, and the lateral rectus muscle for monitoring of CN III, IV, and VI, respectively. Partial neuromuscular blockade was achieved by controlled infusion of vecuronium titrated to eliminate about 90% of the twitch response of the abductor pollicis brevis to electrical stimulation of the median nerve. A total of 30 cranial nerves were stimulated intraoperatively. Of these, 29 were successfully monitored (19 CN III, 6 CN IV, 4 CN VI). A relationship was found between intraoperative findings of cranial nerve monitoring, such as disappearance of response and increase in latency and stimulus threshold during manipulation of a lesion, and the presence of postoperative nerve deficits. We conclude that intraoperative electromyographic monitoring of ocular motor nerves is feasible during partial neuromuscular blockade, and that partial neuromuscular blockade does not affect the relationship between findings of intraoperative monitoring and postoperative nerve function. PMID:17170948

  16. Vascular grafts in microvascular surgery. An experimental study

    SciTech Connect

    Marrangoni, A.G.; Marcelli, G.; Culig, M.; Simone, S.T.

    1988-02-01

    The patency of microvascular grafts depends on the luminal diameter, which is determined by the amount of fibrin and platelets deposited on the intraluminal surface and the anastomotic site, and the extent of pseudointimal formation. An experimental microvascular model in rats has been developed in our laboratory using Indium-111-labeled platelets to measure the amount of deposition on grafts inserted into the infrarenal aorta. This study was designed to assess the patency rates in these grafts and the pathologic maturation as determined by light and electron microscopy. Our study suggests that substantial patency rates can be achieved in aspirin-treated rats, although there was little influence on the pathologic maturation. Indium-111 oxine-labeled platelets can be used to document platelet aggregation, and the technique can be a valuable adjunct in the study of microvascular grafts.

  17. An experimental investigation on the ultimate strength of epoxy repaired braced partial infilled RC frames

    NASA Astrophysics Data System (ADS)

    Dubey, Shailendra Kumar Damodar; Kute, Sunil

    2014-09-01

    Due to earthquake, buildings are damaged partially or completely. Particularly structures with soft storey are mostly affected. In general, such damaged structures are repaired and reused. In this regard, an experimental investigation was planned and conducted on models of single-bay, single-storey of partial concrete infilled reinforced concrete (RC) frames up to collapse with corner, central and diagonal steel bracings. Such collapsed frames were repaired with epoxy resin and retested. The initiative was to identify the behaviour, extent of restored ultimate strength and deflection of epoxy-retrofitted frames in comparison to the braced RC frames. The performance of such frames has been considered only for lateral loads. In comparison to bare RC frames, epoxy repaired partial infilled frames have significant increase in the lateral load capacity. Central bracing is more effective than corner and diagonal bracing. For the same load, epoxy repaired frames have comparable deflection than similar braced frames.

  18. Dehydration of post-mortem eyes for practice and experimental surgery.

    PubMed

    Swinger, C A; Kornmehl, E W

    1985-03-01

    A technique has been developed that allows for rapid dehydration of the cornea of an intact globe. This technique results in a marked improvement in corneal clarity and visualization of anterior chamber structures. Treated eyes can be used for practice and experimental surgery.

  19. Experimental observation of truncated fractional Fourier transform for a partially coherent Gaussian Schell-model beam.

    PubMed

    Wang, Fei; Cai, Yangjian; Lin, Qiang

    2008-08-01

    The truncated fractional Fourier transform (FRT) is applied to a partially coherent Gaussian Schell-model (GSM) beam. The analytical propagation formula for a partially coherent GSM beam propagating through a truncated FRT optical system is derived by using a tensor method. Furthermore, we report the experimental observation of the truncated FRT for a partially coherent GSM beam. The experimental results are consistent with the theoretical results. Our results show that initial source coherence, fractional order, and aperture width (i.e., truncation parameter) have strong influences on the intensity and coherence properties of the partially coherent beam in the FRT plane. When the aperture width is large, both the intensity and the spectral degree of coherence in the FRT plane are of Gaussian distribution. As the aperture width decreases, the diffraction pattern gradually appears in the FRT plane, and the spectral degree of coherence becomes of non-Gaussian distribution. As the coherence of the initial GSM beam decreases, the diffraction pattern for the case of small aperture widths gradually disappears.

  20. Production of ferroan andesites by the experimental partial melting of an LL chondrite

    NASA Technical Reports Server (NTRS)

    Mcguire, J. C.; Jurewicz, A. J. G.; Jones, J. H.

    1994-01-01

    A partial melting experiment on the St. Severin (LL) chondrite produced a melt that was andesitic, having 54-60 wt% silica, at 1200 C and an oxygen fugacity of IW+2, two log units above the iron-wustite (IW) buffer. Under these same conditions, CV, CM, and L chondrites produced low-silica melts resembling angrites. This experimental study attempts to reproduce and explain this unusual result.

  1. Inhibitory simple partial (non-convulsive) status epilepticus after intracranial surgery

    PubMed Central

    Armon, C.; Radtke, R.; Friedman, A.

    2000-01-01

    OBJECTIVES—To report on five patients who developed, 2 to 4 days after an intracranial neurosurgical procedure, new, persistent, focal neurological deficits which were due to inhibitory simple partial (non-convulsive) status epilepticus, and resolved with anticonvulsant treatment.
METHODS—The age range of the five patients was 15-74 years. The operations were: aneurysm clipping (three patients) and resections of an oligodendroglioma and a cavernous haemangioma (one patient each). The new focal deficits were: right hemiparesis and aphasia (two patients), aphasia alone (two patients), and left hemiparesis (one patient). The deficits were not explained by CT (obtained in all patients) or cerebral angiography (performed in two).
RESULTS—Electroencephalography showed, in all patients, continuous or intermittent focal seizures arising from cortex regionally relevant to the clinical dysfunction. Subtle positive epileptic phenomena (jerking) occurred intermittently in three patients as a late concommitant. Administration of anticonvulsant drugs resulted in significant improvement within 24 hours in four patients, with parallel resolution of ictal EEG activity. The fifth patient improved more slowly. Two patients relapsed when anticonvulsant concentrations fell, and improved again when they were raised.
CONCLUSIONS—It is suggested that inhibitory simple partial (non-convulsive) status epilepticus be considered in the differential diagnosis when a new unexplained neurological deficit develops after an intracranial neurosurgical procedure. An EEG may help to diagnose this condition, leading to definitive treatment.

 PMID:10864598

  2. Two-Point Incremental Forming with Partial Die: Theory and Experimentation

    NASA Astrophysics Data System (ADS)

    Silva, M. B.; Martins, P. A. F.

    2013-04-01

    This paper proposes a new level of understanding of two-point incremental forming (TPIF) with partial die by means of a combined theoretical and experimental investigation. The theoretical developments include an innovative extension of the analytical model for rotational symmetric single point incremental forming (SPIF), originally developed by the authors, to address the influence of the major operating parameters of TPIF and to successfully explain the differences in formability between SPIF and TPIF. The experimental work comprised the mechanical characterization of the material and the determination of its formability limits at necking and fracture by means of circle grid analysis and benchmark incremental sheet forming tests. Results show the adequacy of the proposed analytical model to handle the deformation mechanics of SPIF and TPIF with partial die and demonstrate that neck formation is suppressed in TPIF, so that traditional forming limit curves are inapplicable to describe failure and must be replaced by fracture forming limits derived from ductile damage mechanics. The overall geometric accuracy of sheet metal parts produced by TPIF with partial die is found to be better than that of parts fabricated by SPIF due to smaller elastic recovery upon unloading.

  3. Pain management in video assisted thoracic surgery: evaluation of localised partial rib resection. A new technique.

    PubMed

    Richardson, J; Sabanathan, S

    1995-10-01

    We undertook a re-evaluation of acute and chronic pain generation following Video Assisted Thoracic Surgery (VATS) with regard to chest wall trauma produced by the instruments and their ports. From intercostal space (ICS) measurements made on 40 patients, it was confirmed that both the camera and the staple gun port diameters are too large for insertion without trauma. An instrument was produced (the "Sari" Punch, Bolton Surgical Services, Sheffield, England) which cleanly excises an elipse of the superior aspect of a rib, prior to the introduction of the ports. At the same time, the recommended orbit of the instruments about the surgical focus was abandoned in favour of an alignment along one ICS so that only one nerve was potentially traumatised. These modifications were then combined with balanced, pre-emptive and continuous paravertebral analgesia and the efficacy of this approach was evaluated in nine patients undergoing VATS. Operation of the rib punch was easy in all patients and was carried out without clinical or radiological trauma to the rib. Insertion of the ports was easy and access was good to all intrathoracic structures. Postoperative analgesia was good and the mean hospital stay was 2.7 days (range 2-4). Follow-up two months later confirmed a satisfactory surgical procedure and no patients complained of chest wall pain or numbness. We conclude that pain generation with VATS must be seriously considered if the technique is to become truly successful. Balanced, pre-emptive, paravertebral analgesia will protect the central nervous system while the removal of an elipse of rib and alignment of the instruments along one ICS will reduce the likelihood of peripheral nerve trauma.

  4. [Some notes on the history of the experimental surgery laboratory. Reflections on its relevance in education and surgical research].

    PubMed

    de la Garza-Rodea, Anabel Sofía; Padilla-Sánchez, Luis; de la Garza-Aguilar, Javier; Neri-Vela, Rolando

    2007-01-01

    The progress of medicine has largely been due to research, and for surgery, in particular, the experimental surgical laboratory has been considered fundamental to the surgeon's education. In this study, a general view of experimental surgery is given in animal models based on bioethical norms as well as to design, create and apply different surgical procedures before performing in humans. Experimental surgery also facilitates surgical teaching and promotes the surgeon's scientific reasoning. Methods. This is a retrospective and descriptive study. Data were collected from direct and indirect sources of available publications on the historical, bioethical and educational aspects of medicine, focusing on surgery. The important facts corresponding to the field of experimental surgery and applicable in Mexico were selected. Concepts of experimental surgical models and of the experimental surgery laboratory were described. Bioethical considerations are emphasized for care of experimental animals. Finally, this work focuses on the importance of surgical experimentation in current and future development of the surgical researcher. Conclusions. Experimentation with animal models in a surgical laboratory is essential for surgical teaching and promotes development of the scientific thought in the surgeon. It is necessary for surgical research and is fundamental for making progress in surgery, treatment and medicine as science.

  5. Aminophylline partially prevents the decrease of body temperature during laparoscopic abdominal surgery.

    PubMed

    Kim, Dae Woo; Lee, Jung Ah; Jung, Hong Soo; Joo, Jin Deok; In, Jang Hyeok; Jeon, Yeon Soo; Chun, Ga Young; Choi, Jin Woo

    2014-08-01

    Aminophylline can elicit thermogenesis in rats or increase metabolic rate during cold stress in lambs. We tested the hypothesis that aminophylline would reduce the change in core body temperature during laparoscopic abdominal surgery requiring pneumoperitoneum. Fifty patients were randomly divided into an aminophylline group (n=25) and a saline control group (n=25). Esophageal temperature, index finger temperature, and hemodynamic variables, such as mean blood pressure and heart rate, were measured every 15 min during sevoflurane anesthesia. In the aminophylline group, esophageal temperatures at T45 (36.1±0.38 vs. 35.7±0.29, P=0.024), T60 (36.0±0.39 vs. 35.6±0.28, P=0.053), T75 (35.9±0.34 vs. 35.5±0.28, P=0.025), T90 (35.8±0.35 vs. 35.3±0.33, P=0.011), and T105 (35.8±0.36 vs. 35.1±0.53, P=0.017) and index finger temperatures at T15 (35.8±0.46 vs. 34.9±0.33, P<0.001), T30 (35.7±0.36 vs. 35.0±0.58, P=0.029), T45 (35.8±0.34 vs. 35.2±0.42, P=0.020), T60 (35.7±0.33 vs. 34.9±0.47, P=0.010), T75 (35.6±0.36 vs. 34.8±0.67, P=0.028), T90 (35.4±0.55 vs. 34.4±0.89, P=0.042), and T105 (34.9±0.53 vs. 33.9±0.85, P=0.024) were significantly higher than in the saline control group. Aminophylline is effective in maintaining the core temperature through a thermogenic effect, despite reduced peripheral thermoregulatory vasoconstriction.

  6. Margin and complication rates in clampless partial nephrectomy: a comparison of open, laparoscopic and robotic surgeries.

    PubMed

    Mearini, Luigi; Nunzi, Elisabetta; Vianello, Alberto; Di Biase, Manuel; Porena, Massimo

    2016-06-01

    In performing partial nephrectomy (PN), surgeons focus on complete removal of tumor, preservation of renal function, the absence of major perioperative complications, expressed by the formula margin, ischemia and complication (MIC). The aim of current study was to perform a single-institution comparison of clampless open (OPN), laparoscopic (LPN) or robot-assisted (RAPN) PN as well as to evaluate pre-, intra- and postoperative factors that may influence achievement of ideal MIC. All consecutive clampless OPN, LPN or RAPN performed by experienced surgeons between 2006 and 2015 were included in the analysis. MIC was defined as negative surgical margin plus zero-ischemia plus absence of any grade ≥3 complications according to Clavien-Dindo classification. Bivariate and multivariate logistic regression models were fitted to predict the MIC. Odds ratios with 95 % confidence intervals were calculated. 80 patients underwent OPN, 66 LPN and 31 RAPN, and both groups had similar characteristics. The MIC rate was 67.5, 86.3 and 83.3 % in the OPN, LPN and RAPN groups, respectively (p = 0.016). At logistic regression analysis, surgical approach (p = 0.03) and operative time (p = 0.008) were independent predictors of the MIC rate. When stratified according to the surgical approach, preoperative aspects and dimensions used for an anatomical classification (PADUA) score, LPN, RAPN and operative time were independent predictors of MIC rate (p = 0.0488, p = 0.0494, p = 0.0479 and p = 0.0108, respectively). Clampless LPN and RAPN have an efficacy and safety profile that is on par with OPN, offering the additional benefits of a reduced operative time, blood loss, on demand ischemia and rate of high-grade complications.

  7. PRONE ACCELERATED PARTIAL BREAST IRRADIATION AFTER BREAST-CONSERVING SURGERY: FIVE YEAR RESULTS OF 100 PATIENTS

    PubMed Central

    Formenti, Silvia C.; Hsu, Howard; Fenton-Kerimian, Maria; Roses, Daniel; Guth, Amber; Jozsef, Gabor; Goldberg, Judith D.; DeWyngaert, J. Keith

    2013-01-01

    Purpose To report the 5-year results of a prospective trial of three-dimensional conformal external beam radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation in the prone position (P-APBI). Methods Post-menopausal patients with Stage I breast cancer with non palpable <2 cm tumors, negative margins, and negative nodes, positive hormonal receptors, and no extensive intraductal component (EIC) were eligible. The trial was offered only once eligible patients had refused to undergo standard whole-breast radiotherapy. Patients were simulated and treated on a dedicated table for prone set-up. The 3D-CRT delivered was 30 Gy in five 6 Gy/daily fractions over 10 days with port film verification at each treatment. Ipsilateral breast, ipsilateral nodal, contralateral breast, and distant failure (IBF, INF, CBF, DF) were estimated using the cumulative incidence method. Disease-free, overall, and cancer-specific survival (DFS, OS, CSS) were recorded. Results One hundred patients accrued to this IRB- approved prospective trial, one with bilateral breast cancer. One patient withdrew consent after simulation and another elected to interrupt radiotherapy after receiving two treatments. Ninety-eight patients are evaluable for toxicity and, in one case, both breasts were treated with PBI. Median patient age was 68 years (range 53–88 years); in 55% the tumor size was <1 cm. All patients had hormonal receptor positive cancers: 87% underwent adjuvant anti-hormonal therapy. At a median follow-up of 64 months (range, 2–125 months), there was one local recurrence (1% IBF) and one contralateral breast cancer (1% CBF). There were no deaths due to breast cancer by 5 years. Grade 3 late toxicities occurred in 2 patients (1 breast edema, 1 transient breast pain). Cosmesis was rated good/excellent in 89% of patients with at least 36 months follow-up. Conclusions Five-year efficacy and toxicity of 3D-CRT to deliver prone-PBI are comparable to other experiences with similar

  8. Prone Accelerated Partial Breast Irradiation After Breast-Conserving Surgery: Compliance to the Dosimetry Requirements of RTOG-0413

    SciTech Connect

    Wen Bixiu; Hsu, Howard; Formenti-Ujlaki, George F.; Lymberis, Stella; Magnolfi, Chiara; Zhao Xuan; Chang Jenghwa; DeWyngaert, J. Keith; Jozsef, Gabor; Formenti, Silvia C.

    2012-11-15

    Purpose: The dosimetric results from our institution's trials of prone accelerated partial breast irradiation are compared with the dosimetric requirements of RTOG-0413. Methods and Materials: Trial 1 and Trial 2 are 2 consecutive trials of prone-accelerated partial breast irradiation. Eligible for both trials were stage I breast cancer patients with negative margins after breast-conserving surgery. The planning target tumor volume (PTV) was created by extending the surgical cavity 2.0 cm for Trial 1 and 1.5 cm for Trial 2, respectively. Contralateral breast, heart, lungs, and thyroid were contoured. Thirty Gray was delivered in five daily fractions of 6 Gy by a three-dimensional conformal radiation therapy technique in Trial 1 and were by image-guided radiation therapy/intensity-modulated radiation therapy in Trial 2. Dosimetric results from the trials are reported and compared with RTOG 0413 requirements. Results: One hundred forty-six consecutive plans were analyzed: 67 left and 79 right breast cancers. The plans from the trials complied with the required >90% of prescribed dose covering 90% of PTV{sub E}VAL (=generated from the PTV by cropping 0.5 cm from the skin edge and excluding the chest wall): V90% was 98.1 {+-} 3.0% (with V100% and V95%, 89.4 {+-} 12.8%, 96.4 {+-} 5.1%, respectively). No significant difference between laterality was found (Student's t test). The dose constraints criteria of the RTOG-0413 protocol for ipsilateral and contralateral lung (V30 <15% and Dmax <3%), heart (V5 <40%), and thyroid (Dmax <3%) were satisfied because the plans showed an average V5% of 0.6% (range, 0-13.4) for heart, an average V30% of 0.6% (range, 0-9.1%) for ipsilateral lung, and <2% maximum dose to the thyroid. However, our partial breast irradiation plans demonstrated a higher dose to contralateral breast than that defined by RTOG constraints, with a median value of maximum doses of 4.1% (1.2 Gy), possibly as a result of contouring differences. Conclusions: Our

  9. Pilot study of the Korean Parent Training Program using a partial group randomized experimental study

    PubMed Central

    Kim, Eunjung; Cain, Kevin; Boutain, Doris; Chun, Jin-Joo; Kim, Sangho; Im, Hyesang

    2017-01-01

    Problems Korean American (KA) children experience mental health problems due to difficulties in parenting dysfunction complicated by living in two cultures. Methods Korean Parent Training Program (KPTP) was pilot tested with 48 KA mothers of children (ages 3–8) using partial group randomized controlled experimental study design. Self-report survey and observation data were gathered. Findings Analyses using generalized estimating equation indicated the intervention group mothers increased effective parenting and their children decreased behavior problems and reported less acculturation conflict with mothers. Conclusions The KPTP is a promising way to promote effective parenting and increase positive child mental health in KA families. PMID:24645901

  10. Catalytic partial oxidation of iso-octane over rhodium catalysts: An experimental, modeling, and simulation study

    SciTech Connect

    Hartmann, M.; Minh, H.D.; Maier, L.; Deutschmann, O.

    2010-09-15

    Catalytic partial oxidation of iso-octane over a rhodium/alumina coated honeycomb monolith is experimentally and numerically studied at short-contact times for varying fuel-to-oxygen ratios. A new experimental set-up with well-defined inlet and boundary conditions is presented. The conversion on the catalyst and in the gas-phase is modeled by detailed reaction mechanisms including 857 gas-phase and 17 adsorbed species. Elementary-step based heterogeneous and homogeneous reaction mechanisms are implemented into two-dimensional flow field description of a single monolith channel. Experiment and simulation provide new insights into the complex reaction network leading to varying product distribution as function of fuel-to-oxygen ratio. At fuel rich conditions, the formation of by-products that can serve as coke precursors is observed and interpreted. (author)

  11. Comparison between blinded and partially blinded detection of gastric cancer with multidetector CT using surgery and endoscopic submucosal dissection as reference standards.

    PubMed

    Kim, H J; Lee, D H; Ko, Y T

    2010-08-01

    The aim of this study is to compare blinded with partially blinded detection of gastric cancer with multidetector (MD) CT by using surgery and endoscopic submucosal dissection (ESD) as reference standards. 44 patients with gastric cancer underwent MDCT with air as an oral contrast agent. Surgery was performed on 37 patients, ESD on six and surgery after ESD on one. To provide comparison cases of blinded evaluation, 38 MDCT examinations were added for cases where no focal gastric lesion was seen on endoscopy. Two radiologists, blinded to the presence, number and location of the tumours, evaluated axial and axial plus multiplanar reformation (MPR) images of 82 MDCT examinations with or without gastric cancer. For partially blinded evaluation, the same radiologists, blinded to the location and number of tumours, evaluated axial and axial plus MPR images of 44 MDCT examinations of gastric cancer. Differences in assessment were resolved by consensus. 45 gastric cancers were found in surgical and ESD specimens. Detection rates of gastric cancer from axial and axial plus MPR images during blinded evaluation and from axial and axial plus MPR images during partially blinded evaluation were 62% (28/45), 64% (29/45), 64% (29/45) and 71% (32/45), respectively. There was no statistical significance for the comparison between blinded and partially blinded detection rates of gastric cancer. The detection rate of gastric cancer with MDCT during blinded evaluation showed no specific difference compared with the detection rate of gastric cancer with MDCT during partially blinded evaluation.

  12. TRANEXAMIC ACID ACTION ON LIVER REGENERATION AFTER PARTIAL HEPATECTOMY: EXPERIMENTAL MODEL IN RATS

    PubMed Central

    SOBRAL, Felipe Antonio; DAGA, Henrique; RASERA, Henrique Nogueira; PINHEIRO, Matheus da Rocha; CELLA, Igor Furlan; MORAIS, Igor Henrique; MARQUES, Luciana de Oliveira; COLLAÇO, Luiz Martins

    2016-01-01

    ABSTRACT Background: Different lesions may affect the liver resulting in harmful stimuli. Some therapeutic procedures to treat those injuries depend on liver regeneration to increase functional capacity of this organ. Aim: Evaluate the effects of tranexamic acid on liver regeneration after partial hepatectomy in rats. Method: 40 rats (Rattus norvegicus albinus, Rodentia mammalia) of Wistar-UP lineage were randomly divided into two groups named control (CT) and tranexamic acid (ATX), with 20 rats in each. Both groups were subdivided, according to liver regeneration time of 32 h or seven days after the rats had been operated. The organ regeneration was evaluated through weight and histology, stained with HE and PCNA. Results: The average animal weight of ATX and CT 7 days groups before surgery were 411.2 g and 432.7 g, and 371.3 g and 392.9 g after the regeneration time, respectively. The average number of mitotic cells stained with HE for the ATX and CT 7 days groups were 33.7 and 32.6 mitosis, and 14.5 and 14.9 for the ATX and CT 32 h groups, respectively. When stained with proliferating cell nuclear antigen, the numbers of mitotic cells counted were 849.7 for the ATX 7 days, 301.8 for the CT 7 days groups, 814.2 for the ATX 32 hand 848.1 for the CT 32 h groups. Conclusion: Tranexamic acid was effective in liver regeneration, but in longer period after partial hepatectomy. PMID:27438036

  13. Experimental Measurement of Frozen and Partially Melted Water Droplet Impact Dynamics

    NASA Technical Reports Server (NTRS)

    Palacios, Jose; Yan, Sihong; Tan, Jason; Kreeger, Richard E.

    2014-01-01

    High-speed video of single frozen water droplets impacting a surface was acquired. The droplets diameter ranged from 0.4 mm to 0.9 mm and impacted at velocities ranging from 140 m/sec to 309 m/sec. The techniques used to freeze the droplets and launch the particles against the surfaces is described in this paper. High-speed video was used to quantify the ice accretion area to the surface for varying impact angles (30 deg, 45 deg, 60 deg), impacting velocities, and break-up angles. An oxygen /acetylene cross-flow flame used to ensure partial melting of the traveling frozen droplets is also discussed. A linear relationship between impact angle and ice accretion is identified for fully frozen particles. The slope of the relationship is affected by impact speed. Perpendicular impacts, i.e. 30 deg, exhibited small differences in ice accretion for varying velocities, while an increase of 60% in velocity from 161 m/sec to 259 m/sec, provided an increase on ice accretion area of 96% at an impact angle of 60 deg. The increase accretion area highlights the importance of impact angle and velocity on the ice accretion process of ice crystals. It was experimentally observed that partial melting was not required for ice accretion at the tested velocities when high impact angles were used (45 and 60 deg). Partially melted droplets doubled the ice accretion areas on the impacting surface when 0.0023 Joules were applied to the particle. The partially melted state of the droplets and a method to quantify the percentage increase in ice accretion area is also described in the paper.

  14. Structures and rheology of syn-kinematic partially molten gneiss: an experimental approach.

    NASA Astrophysics Data System (ADS)

    Anne-Céline, Ganzhorn; Laurent, Arbaret; Rémi, Champallier; Loic, Labrousse; Gaëlle, Prouteau

    2013-04-01

    Partial melting of the continental crust is a weakening process prone to induce ductile flow of orogens. The presence of melts indeed affects both the thermal and rheological behavior of the crust during orogeny, probably since the very first percents of partial melting. The rheological laws of the partially molten crustal rocks often refer to deformation experiments of synthetic metapelites with well-constrained composition but less realistic initial textures. This study focuses on the experimental deformation of a natural two-micas gneiss from the Western Gneiss Region, Norway, in order to constrain its rheological and textural behaviors when subjected to low temperature (750°C) water-present melting. Two starting materials were used for Paterson experiments. Cores of a dry gneiss were prepared while others were first hydrated at room temperature and loaded in the bore furnace of an internally heated pressure vessel at 750°C and 300 MPa during 48 hours, then isobarically quenched. The partially molten gneiss contain up to 20% of hydrated glass that forms a 20 µm thick film isotropically distributed at muscovite-quartz grain boundaries. The dry gneiss submitted to similar P/T conditions remained un-melted. Thin films of melt only appear at temperature above 850°C for the same pressure. Axial deformation experiments were performed with both dry and pre-hydrated cores in a gas medium Paterson apparatus at constant 300 MPa confining pressure and two temperatures of 750°C and 850°C. Axial stress was applied perpendicularly to the mineral foliation; finite strain varied from 14% to 23%. Varying strain rates from 5x10-6 to 10-4 s-1 allowed us to determine the rheological behaviour of the hydrated gneiss. We found a shear thinning behaviour with stress at T = 750°C. In addition, the measured stress at this temperature is reduced by one order of magnitude between the dry gneiss (2.5x109 Pa) and the partially molten gneiss (<2.5x108 Pa). SEM textural analysis

  15. Custom prefabrication of silicone tubes from urinary catheters for experimental peripheral nerve surgery

    PubMed Central

    Saray, Aydin

    2004-01-01

    The entubulation principle represents a neurobiological approach to nerve surgery in which the role of the surgeon is limited and intrinsic healing capabilities of the nerve play the primary role. Herein, a technique for fabricating custom-made silicone tubes from a silicone urinary catheter is described. Silicone tubes with varying size and dimensions can be tailored depending on the diameter of the silicone urinary catheter (14 F to 18 F). Tubes crafted from silicone urinary catheters were used either as a nerve conduit to facilitate regeneration or as compressive nerve banding to simulate compressive neuropathy in the rat sciatic nerve. Custom-made silicone tubes have similar pros and cons to the commercially available silicone tubes regarding the capsule and foreign body reaction. It can be concluded that these cost effective tubes can be easily cut and used in experimental peripheral nerve surgery in developing countries where the cost of such materials becomes an important issue for the researchers. PMID:24115867

  16. Experimental deformation of partially molten granite and implications for strain localization

    NASA Astrophysics Data System (ADS)

    Goncalves, L.; Hirth, G.; Alkmim, F.; Pedrosa-Soares, A.; Goncalves, C.

    2011-12-01

    To improve our understanding of partially molten systems we conducted a set of hydrostatic, general shear and axial compression experiments on sintered aggregates composed of equal amounts by weight of quartz, albite and microcline (grain size of 37-53μm). All experiments were conducted using a Griggs solid medium apparatus at T=900°C, P=1.5GPa and strain rates from 10-4/s to 10-6/s. Previous hydrostatic and axial compression experiments conducted on partial molten granitic rocks have shown that the initial grain size, amount of melt and strain rate are important parameters for the development of distinct microstructures, LPO, and melt distribution. In addition, some of these studies demonstrated that the strength of granite and aplite decrease significantly for melt contents up to 15%, when compared to similar melt-free rocks. The rock's strength deep within the Earth decreases owing to partial melting which brings up some questions: would strain localization take place when partial melt affects rheology? Would brittle and/or ductile shear zones act as potential regions for concentration of partial melt? Is there a critical fraction of melt responsible for strain localization? How is melt distribution influenced by deformation? How does the kinematics of deformation (i.e., axial compression versus general shear) affect melt distribution? The purpose of our experiments is to investigate the role of melting on the rheological properties of crustal rocks. In addition, we seek to provide new constraints on the grain scale processes that control the properties of partially molten rocks and the importance of these processes in understanding shear localization in the lithosphere. Samples were made from crushed Amelia albite (Ab97Or2An1), Hugo Microcline (Or90) and Black Hills quartzite, which have all been used in previous experimental deformation studies. The albite is essentially pure; the microcline contains ~ 1% of muscovite. The Black Hills quartzite contains < 1

  17. Experimental test of the viscous anisotropy hypothesis for partially molten rocks.

    PubMed

    Qi, Chao; Kohlstedt, David L; Katz, Richard F; Takei, Yasuko

    2015-10-13

    Chemical differentiation of rocky planets occurs by melt segregation away from the region of melting. The mechanics of this process, however, are complex and incompletely understood. In partially molten rocks undergoing shear deformation, melt pockets between grains align coherently in the stress field; it has been hypothesized that this anisotropy in microstructure creates an anisotropy in the viscosity of the aggregate. With the inclusion of anisotropic viscosity, continuum, two-phase-flow models reproduce the emergence and angle of melt-enriched bands that form in laboratory experiments. In the same theoretical context, these models also predict sample-scale melt migration due to a gradient in shear stress. Under torsional deformation, melt is expected to segregate radially inward. Here we present torsional deformation experiments on partially molten rocks that test this prediction. Microstructural analyses of the distribution of melt and solid reveal a radial gradient in melt fraction, with more melt toward the center of the cylinder. The extent of this radial melt segregation grows with progressive strain, consistent with theory. The agreement between theoretical prediction and experimental observation provides a validation of this theory.

  18. Experimental test of the viscous anisotropy hypothesis for partially molten rocks

    PubMed Central

    Qi, Chao; Kohlstedt, David L.; Katz, Richard F.; Takei, Yasuko

    2015-01-01

    Chemical differentiation of rocky planets occurs by melt segregation away from the region of melting. The mechanics of this process, however, are complex and incompletely understood. In partially molten rocks undergoing shear deformation, melt pockets between grains align coherently in the stress field; it has been hypothesized that this anisotropy in microstructure creates an anisotropy in the viscosity of the aggregate. With the inclusion of anisotropic viscosity, continuum, two-phase-flow models reproduce the emergence and angle of melt-enriched bands that form in laboratory experiments. In the same theoretical context, these models also predict sample-scale melt migration due to a gradient in shear stress. Under torsional deformation, melt is expected to segregate radially inward. Here we present torsional deformation experiments on partially molten rocks that test this prediction. Microstructural analyses of the distribution of melt and solid reveal a radial gradient in melt fraction, with more melt toward the center of the cylinder. The extent of this radial melt segregation grows with progressive strain, consistent with theory. The agreement between theoretical prediction and experimental observation provides a validation of this theory. PMID:26417107

  19. Design and Experimental Performance of a Two Stage Partial Admission Turbine, Task B.1/B.4

    NASA Technical Reports Server (NTRS)

    Sutton, R. F.; Boynton, J. L.; Akian, R. A.; Shea, Dan; Roschak, Edmund; Rojas, Lou; Orr, Linsey; Davis, Linda; King, Brad; Bubel, Bill

    1992-01-01

    A three-inch mean diameter, two-stage turbine with partial admission in each stage was experimentally investigated over a range of admissions and angular orientations of admission arcs. Three configurations were tested in which first stage admission varied from 37.4 percent (10 of 29 passages open, 5 per side) to 6.9 percent (2 open, 1 per side). Corresponding second stage admissions were 45.2 percent (14 of 31 passages open, 7 per side) and 12.9 percent (4 open, 2 per side). Angular positions of the second stage admission arcs with respect to the first stage varied over a range of 70 degrees. Design and off-design efficiency and flow characteristics for the three configurations are presented. The results indicated that peak efficiency and the corresponding isentropic velocity ratio decreased as the arcs of admission were decreased. Both efficiency and flow characteristics were sensitive to the second stage nozzle orientation angles.

  20. Towards robotic heart surgery: introduction of autonomous procedures into an experimental surgical telemanipulator system.

    PubMed

    Bauernschmitt, R; Schirmbeck, E U; Knoll, A; Mayer, H; Nagy, I; Wessel, N; Wildhirt, S M; Lange, R

    2005-09-01

    The introduction of telemanipulator systems into cardiac surgery enabled the heart surgeon to perform minimally invasive procedures with high precision and stereoscopic view. For further improvement and especially for inclusion of autonomous action sequences, implementation of force-feedback is necessary. The aim of our study was to provide a robotic scenario giving the surgeon an impression very similar to open procedures (high immersion) and to enable autonomous surgical knot tying with delicate suture material. In this experimental set-up the feasibility of autonomous surgical knot tying is demonstrated for the first time using stereoscopic view and force feedback.

  1. Experimental model for bone regeneration in oral and cranio-maxillo-facial surgery.

    PubMed

    Mardas, Nikos; Dereka, Xanthippi; Donos, Nikolaos; Dard, Michel

    2014-02-01

    Bone and tooth loss, as a result of trauma, anatomical or congenital reasons, cancer, and periodontal disease, is a common therapeutic problem in the fields of cranio-maxillo-facial surgery and periodontics. The proposed techniques for the treatment of various bone defects encountered include bone grafts, bone substitutes, guided tissue regeneration, and distraction osteogenesis as well as their combinations. In addition, dental implants have been successfully utilized for the restoration of full or partial edentulism. The introduction and development of new therapeutic approaches and devices demand the use of appropriate animal models that present bone anatomy and healing comparable to human. Among other animal models, the pig is extensively documented in several biomedical areas and has been largely used in maxillo-facial surgery and implants dentistry-related research. Anatomical and physiological similarities with human in size, physiology, and bone biology contribute to a successful involvement of this animal to understand and treat various osseous lesions. However, improvements and standardization are requested with respect to consistency and discrimination abilities. The aim of this review is to provide a critical appraisal of the literature related to swine models for the evaluation of cranio-maxillo-facial osseous defect healing, regeneration, and bone-implant interface. This review should assist researchers in the field to select the most appropriate model for each dedicated purpose and also contribute to stimulate an innovative thinking on the use of porcine models.

  2. Experimental Spinel Standards for Ferric Iron (Fe3+) Determination During Peridotite Partial Melting

    NASA Astrophysics Data System (ADS)

    Wenz, M. D.; Sorbadere, F.; Rosenthal, A.; Frost, D. J.; McCammon, C. A.

    2014-12-01

    The presence of ferric iron (Fe3+) in the mantle plays a significant role in the oxygen fugacity (fO2) of the Earth's interior. This has a wide range of implications for Earth related processes ranging from the composition of the atmosphere to magmatic phase relations during melting and crystallization processes [1]. A major source of Earth's mantle magmas is spinel peridotite. Despite its low abundance, spinel (Fe3+/ƩFe = 15-34%, [2]) is the main contributor of Fe3+to the melt upon partial melting. Analyses of Fe3+ on small areas of spinel and melt are required to study the Fe3+ behavior during partial melting of spinel peridotite. Fe K-edge X-ray Absorption Near Edge Structure (XANES) combines both high precision and small beam size, but requires standards with a wide range of Fe3+ content to obtain good calibration. Glasses with varying Fe3+ content are easily synthesized [3, 4]. Spinel, however, presents a challenge for experimental standards due to the low diffusion of Cr and Al preventing compositional homogeneity. Natural spinel standards are often used, but only cover a narrow Fe3+ range. Thus, there is a need for better experimental spinel standards over a wider range of fO2. Our study involves making experimental mantle spinels with variable Fe3+ content. We used a sol-gel auto-combustion method to synthesize our starting material [5]. FMQ-2, FMQ+0, and air fO2 conditions were established using a gas mixing furnace. Piston cylinder experiments were performed at 1.5GPa, and 1310 -1370°C to obtain solid material for XANES. To maintain distinct oxidizing conditions, three capsules were used: graphite for reduced, Re for intermediate and AuPd for oxidized conditions. The spinels were analyzed by Mössbauer spectroscopy. Fe3+/ƩFe ranged from 0.3 to 0.6. These values are consistent with the Fe edge position obtained using XANES analyses, between 7130 and 7132 eV, respectively. Our spinels are thus suitable standards for Fe3+ measurements in peridotite

  3. Experimental investigation of virus and clay particles cotransport in partially saturated columns packed with glass beads.

    PubMed

    Syngouna, Vasiliki I; Chrysikopoulos, Constantinos V

    2015-02-15

    Suspended clay particles in groundwater can play a significant role as carriers of viruses, because, depending on the physicochemical conditions, clay particles may facilitate or hinder the mobility of viruses. This experimental study examines the effects of clay colloids on the transport of viruses in variably saturated porous media. All cotransport experiments were conducted in both saturated and partially saturated columns packed with glass beads, using bacteriophages MS2 and ΦX174 as model viruses, and kaolinite (KGa-1b) and montmorillonite (STx-1b) as model clay colloids. The various experimental collision efficiencies were determined using the classical colloid filtration theory. The experimental data indicated that the mass recovery of viruses and clay colloids decreased as the water saturation decreased. Temporal moments of the various breakthrough concentrations collected, suggested that the presence of clays significantly influenced virus transport and irreversible deposition onto glass beads. The mass recovery of both viruses, based on total effluent virus concentrations, was shown to reduce in the presence of suspended clay particles. Furthermore, the transport of suspended virus and clay-virus particles was retarded, compared to the conservative tracer. Under unsaturated conditions both clay particles facilitated the transport of ΦX174, while hindered the transport of MS2. Moreover, the surface properties of viruses, clays and glass beads were employed for the construction of classical DLVO and capillary potential energy profiles, and the results suggested that capillary forces play a significant role on colloid retention. It was estimated that the capillary potential energy of MS2 is lower than that of ΦX174, and the capillary potential energy of KGa-1b is lower than that of STx-1b, assuming that the protrusion distance through the water film is the same for each pair of particles. Moreover, the capillary potential energy is several orders of

  4. Impact of textural anisotropy on syn-kinematic partial melting of natural gneisses: an experimental approach.

    NASA Astrophysics Data System (ADS)

    Ganzhorn, Anne-Céline; Trap, Pierre; Arbaret, Laurent; Champallier, Rémi; Fauconnier, Julien; Labrousse, Loic; Prouteau, Gaëlle

    2015-04-01

    Partial melting of continental crust is a strong weakening process controlling its rheological behavior and ductile flow of orogens. This strength weakening due to partial melting is commonly constrained experimentally on synthetic starting material with derived rheological law. Such analog starting materials are preferentially used because of their well-constrained composition to test the impact of melt fraction, melt viscosity and melt distribution upon rheology. In nature, incipient melting appears in particular locations where mineral and water contents are favorable, leading to stromatic migmatites with foliation-parallel leucosomes. In addition, leucosomes are commonly located in dilatants structural sites like boudin-necks, in pressure shadows, or in fractures within more competent layers of migmatites. The compositional layering is an important parameter controlling melt flow and rheological behavior of migmatite but has not been tackled experimentally for natural starting material. In this contribution we performed in-situ deformation experiments on natural rock samples in order to test the effect of initial gneissic layering on melt distribution, melt flow and rheological response. In-situ deformation experiments using a Paterson apparatus were performed on two partially melted natural gneissic rocks, named NOP1 & PX28. NOP1, sampled in the Western Gneiss Region (Norway), is biotite-muscovite bearing gneiss with a week foliation and no gneissic layering. PX28, sampled from the Sioule Valley series (French Massif Central), is a paragneiss with a very well pronounced layering with quartz-feldspar-rich and biotite-muscovite-rich layers. Experiments were conducted under pure shear condition at axial strain rate varying from 5*10-6 to 10-3 s-1. The main stress component was maintained perpendicular to the main plane of anisotropy. Confining pressure was 3 kbar and temperature ranges were 750°C and 850-900°C for NOP1 and PX28, respectively. For the 750

  5. Theoretical and experimental investigation of thermohydrologic processes in a partially saturated, fractured porous medium

    SciTech Connect

    Green, R.T.; Manteufel, R.D.; Dodge, F.T.; Svedeman, S.J.

    1993-07-01

    The performance of a geologic repository for high-level nuclear waste will be influenced to a large degree by thermohydrologic phenomena created by the emplacement of heat-generating radioactive waste. The importance of these phenomena is manifest in that they can greatly affect the movement of moisture and the resulting transport of radionuclides from the repository. Thus, these phenomena must be well understood prior to a definitive assessment of a potential repository site. An investigation has been undertaken along three separate avenues of analysis: (i) laboratory experiments, (ii) mathematical models, and (iii) similitude analysis. A summary of accomplishments to date is as follows. (1) A review of the literature on the theory of heat and mass transfer in partially saturated porous medium. (2) A development of the governing conservation and constitutive equations. (3) A development of a dimensionless form of the governing equations. (4) A numerical study of the importance and sensitivity of flow to a set of dimensionless groups. (5) A survey and evaluation of experimental measurement techniques. (6) Execution of laboratory experiments of nonisothermal flow in a porous medium with a simulated fracture.

  6. Laxative effects of partially defatted flaxseed meal on normal and experimental constipated mice

    PubMed Central

    2012-01-01

    Background Constipation is a very common health problem in the world. Intake of sufficient amount of dietary fibers is a cornerstone in the prevention and treatment of constipation. As a traditional medicine, flaxseed has been used to treat constipation for centuries, but the controlled trials are rare. The purpose of the present study was to assess that whether partially defatted flaxseed meal (PDFM) has the potential role to facilitate fecal output in normal and experimental constipated mice. Methods After supplemented with 2.5%, 5% and 10% (w/w) PDFM (L-, M- and H -PDFM) for 14 days, the constipation models of mice were induced by atropine-diphenoxylate. The small intestinal transit rates, start time of defecation, amount of defecation and wet weight of feces were researched in normal and constipation model mice. Results M- and H-PDFM significantly increase small intestinal transit rates in constipation model mice. All dose of PDFM markedly shortened the start time of defecation and M- and H-PDFM significantly increase stool frequency and weight in both normal and constipation model mice. Conclusions PDFM may be a useful laxative to facilitate fecal output in normal and constipation conditions. PMID:22400899

  7. Erythropoietin administration partially prevents adipose tissue loss in experimental cancer cachexia models

    PubMed Central

    Penna, Fabio; Busquets, Silvia; Toledo, Miriam; Pin, Fabrizio; Massa, David; López-Soriano, Francisco J.; Costelli, Paola; Argilés, Josep M.

    2013-01-01

    Cancer-associated cachexia is characterized, among other symptoms, by a dramatic loss of both muscle and fat. In addition, the cachectic syndrome is often associated with anemia. The object of the present investigation was to assess the effects of erythropoietin (EPO) treatment on experimental cancer cachexia models. The results clearly show that, in addition to the improvement of the hematocrit, EPO treatment promoted a partial preservation of adipose tissue while exerting negligible effects on muscle loss. Administration of EPO to tumor-bearing animals resulted in a significant increase of lipoprotein lipase (LPL) activity in adipose tissue, suggesting that the treatment favored triacylglycerol (TAG) accumulation in the adipose tissue. In vitro experiments using both adipose tissue slices and 3T3-L1 adipocytes suggests that EPO is able to increase the lipogenic rate through the activation of its specific receptor (EPOR). This metabolic pathway, in addition to TAG uptake by LPL, may contribute to the beneficial effects of EPO on fat preservation in cancer cachexia. PMID:23966665

  8. Ocular explosion during cataract surgery: a clinical, histopathological, experimental, and biophysical study.

    PubMed Central

    Bullock, J D; Warwar, R E; Green, W R

    1998-01-01

    INTRODUCTION: An increasing number of cases are being recognized in which a peribulbar anesthetic for cataract surgery has been inadvertently injected directly into the globe under high pressure until the globe ruptures or explodes. We reviewed the records of 6 such cases (one of which was reported previously by us), and one additional case has been reported in the literature. Surprisingly, 2 of these 7 cases went unrecognized at the time, and the surgeons proceeded with the cataract operation; all of the patients ultimately developed severe visual loss and/or loss of the eye. OBJECTIVES: To reproduce this eye explosion in a live anesthetized rabbit model and to perform a clinical, histopathological, experimental, biophysical, and mathematical analysis of this injury. METHODS: Eyes of live anesthetized rabbits were ruptured by means of the injection of saline directly into the globe under high pressure. The clinical and pathological findings of the ruptured human and animal eyes were documented photographically and/or histopathologically. An experimental, biophysical, and mathematical analysis of the pressures and forces required to rupture the globe via direct injection using human cadavers, human eye-bank eyes, and classic physics and ophthalmic formulas was performed. The laws of Bernoulli, LaPlace, Friedenwald, and Pascal were applied to the theoretical and experimental models of this phenomenon. RESULTS: The clinical and pathological findings of scleral rupture, retinal detachment, vitreous hemorrhage, and lens extrusion were observed. In the exploded human and rabbit eyes, the scleral ruptures appeared at the equator, the limbal area, or the posterior pole. In 2 of the 7 human eyes, the anterior segments appeared entirely normal despite the rupture, and cataract surgery was completed; surgery was canceled in the other 4 cases. In 4 of the 5 injected and ruptured rabbit eyes, the anterior segments appeared essentially normal. The experiments with human eye

  9. Experimental study of continental crust partial melting: rheological and microstructure effects.

    NASA Astrophysics Data System (ADS)

    Fauconnier, Julien; Stünitz, Holger; Rosenberg, Claudio; Labrousse, Loïc; Jolivet, Laurent

    2014-05-01

    Deformation on the orogen-scales involves localization due to weakening, and partial melting of the continental crust is one of the most important weakening agent. In order to understand the causes of melt-induced weakening and the way melt moves through an anisotropic medium (generally consisting of a foliation and/or layering) we conducted a series of high-pressure experiments to deform partially molten, crustal-like materials and compare the experimental microstructures with those of natural migmatites. Deformation experiments were performed in simple shear mode in a Griggs-type apparatus. The starting material consists of 90% quartz powder (crushed Fontainebleau sandstone; 10 to 20 µm grain size) and 10% biotite powder (50 to 100 µm grain size). In order to control the amount of melt, 5% to 10% of haplogranitic glass (HPG) were added to the starting material. Experiments were performed in the biotite stability field, but above the HPG transition temperature (1 GPa confining pressure, temperature between 700°C and 900°C). Deformation took place at a strain rate of 10-5 s-1,to a finite shear strain of up to γ ≡ 4. Our first results show the following features: (1) The presence of melt weakens the sample only during the first increments of deformation (below γ ≡ 2) compared to experiments without glass. (2) Small amounts of weak phase (5% HPG or 10% biotite) result in the nucleation of shear bands which localize deformation. (3) Larger amounts of melt (10% HPG) are associated with weakening by a factor of 3 compared to 5% melt samples, accompanied by a more homogeneously distributed deformation and absence of shear bands. The increase from 5 to 10% HPG changes the microstructures from dominant crystal plasticity of quartz to microstructures indicating grain boundary sliding. (4) Surprisingly, the weakening caused by 5% HPG in a pure quartz sample at 800°C (i.e. 5% melt) is very similar to the weakening effect of 10% biotite (after γ ≡ 2) without melt

  10. Differentiation of Relatively Oxidized Planetesimals: Experimental Partial Melting of Allende at IW+1

    NASA Astrophysics Data System (ADS)

    Lunning, N. G.; McCoy, T. J.; Corrigan, C. M.; Waters, L. E.

    2016-08-01

    Partial melting experiments on CV3 chondrites reveal that oxidized differentiated planetesimals may differ in their interior mineralogy and thermal structure from more "typical" reduced differentiated planetesimals.

  11. Topical infliximab for the suppression of wound healing following experimental glaucoma filtration surgery

    PubMed Central

    Turgut, Burak; Eren, Kenan; Akın, Mehmet Mustafa; Demir, Tamer; Kobat, Sabiha

    2014-01-01

    Background The purpose of this work was to look into the effects of infliximab on wound healing in experimental glaucoma filtration surgery and to compare the antifibrotic effects of this agent to that of mitomycin-C (MMC). Methods Twenty-eight male New Zealand White rabbits were randomly assigned to four groups, each including seven rabbits: control group, sham group, MMC group, and infliximab group. The rabbits in the control group were not operated on and did not receive any treatment. The rabbits in the sham group underwent trabeculectomy and had one drop of saline instilled four times a day for 14 days. The rabbits in the MMC treatment group underwent trabeculectomy, and a sponge soaked in 0.4 mg/mL MMC was applied intraoperatively to the scleral surgical site for three minutes. The rabbits in the infliximab treatment group underwent trabeculectomy and one drop of 10 mg/mL infliximab was instilled four times a day for 14 days after surgery. On day 14 of the experiment, the operated and control eyes were enucleated and histologically and immunohistochemically analyzed. Results The mean fibroblast and mononuclear cell (MNC) numbers and the mean immunostaining intensities of transforming growth factor-β (TGF-β), fibroblast growth factor-β (FGF-β), and platelet-derived growth factor (PDGF) in the sham group were higher than those of the control group (P<0.01). The mean fibroblast and MNC numbers and the mean immunostaining intensities of TGF-β, FGF-β, and PDGF in the MMC and infliximab groups were statistically significantly lower than those of the sham group (P<0.01). The mean fibroblast and MNC numbers and the mean TGF-β, FGF-β, and PDGF immunostaining intensities of the MMC and infliximab groups were similar (P>0.05). Conclusion Our study suggests that topical infliximab effectively suppresses the subconjunctival wound healing response after experimental glaucoma filtration surgery, reducing the MNC and fibroblast numbers and immunostaining intensities

  12. Experimental study on retardation of a heavy NAPL vapor in partially saturated porous media

    NASA Astrophysics Data System (ADS)

    Kleinknecht, Simon Matthias; Class, Holger; Braun, Jürgen

    2017-03-01

    Non-aqueous-phase liquid (NAPL) contaminants introduced into the unsaturated zone spread as a liquid phase; however, they can also vaporize and migrate in a gaseous state. Vapor plumes migrate easily and thus pose a potential threat to underlying aquifers. Large-scale column experiments were performed to quantify partitioning processes responsible for the retardation of carbon disulfide (CS2) vapor in partially saturated porous media. The results were compared with a theoretical approach taking into account the partitioning into the aqueous phase as well as adsorption to the solid matrix and to the air-water interface. The experiments were conducted in large, vertical columns (i.d. of 0.109 m) of 2 m length packed with different porous media. A slug of CS2 vapor and the conservative tracer argon was injected at the bottom of the column followed by a nitrogen chase. Different seepage velocities were applied to characterize the transport and to evaluate their impact on retardation. Concentrations of CS2 and argon were measured at the top outlet of the column using two gas chromatographs. The temporal-moment analysis for step input was employed to evaluate concentration breakthrough curves and to quantify dispersion and retardation. The experiments conducted showed a pronounced retardation of CS2 in moist porous media which increased with water saturation. The comparison with an analytical solution helped to identify the relative contributions of partitioning processes to retardation. Thus, the experiments demonstrated that migrating CS2 vapor is retarded as a result of partitioning processes. Moreover, CS2 dissolved in the bulk water is amenable to biodegradation. The first evidence of CS2 decay by biodegradation was found in the experiments. The findings contribute to the understanding of vapor-plume transport in the unsaturated zone and provide valuable experimental data for the transfer to field-like conditions.

  13. Bevacizumab-Loaded Polyurethane Subconjunctival Implants: Effects on Experimental Glaucoma Filtration Surgery

    PubMed Central

    Ribeiro, Vanessa Raquel Coimbra; Chahud, Fernando; Cannellini, Roberta; Monteiro, Tassia Cristina; de Lima Gomes, Elionai Cassiana; Reinach, Peter Sol; Veronese Rodrigues, Maria de Lourdes; Silva-Cunha, Armando

    2013-01-01

    Abstract Purpose Vascular endothelial growth factor (VEGF) may contribute to the scarring process resulting from glaucoma filtration surgery, since this cytokine may stimulate fibroblast proliferation. The aim of this study was to describe a new bevacizumab-loaded polyurethane implant (BPUI) and to evaluate its effectiveness as a new drug delivery system of anti-VEGF antibody in a rabbit model of glaucoma filtration surgery. Methods An aqueous dispersion of polyurethane was obtained via the conventional process. Bevacizumab (1.5 mg) was then incorporated into the dispersion and was subsequently dried to form the polymeric films. Films with dimensions of 3×3×1 mm that either did (group BPUI, n=10) or did not contain bevacizumab (group PUI, n=10) were implanted in the subconjunctival space, at the surgical site in 1 eye of each rabbit. The in vitro bevacizumab release was evaluated using size-exclusion high-performance liquid chromatography (HPLC), and the in vivo effects of the drug were investigated in a rabbit experimental trabeculectomy model by examining the bleb characteristics and collagen accumulation, and by performing immunohistological analyses of VEGF expression. Results HPLC showed that only 10% of the bevacizumab in the implants had been released by postoperative day 5. In vivo studies demonstrated that the drug had no adverse effects; however, no significant differences in either the bleb area score or the collagen deposit intensity between the group PUI and the group that BPUI were observed. Moreover, the group BPUI presented a significantly lower proportion of VEGF-expressing fibroblasts than group PUI (0.17±0.03 vs. 0.35±0.05 cells/field, P=0.005). Conclusions This study demonstrated that bevacizumab release from the BPUIs only occurred for a short time probably from the surface of the films. Nevertheless, they were well tolerated in rabbit eyes and reduced the number of VEGF-expressing fibroblasts. PMID:23391327

  14. Stannern-Trend Eucrite Petrogenesis: An Assessment of Partial Melt Contamination Models via Experimental Petrology

    NASA Astrophysics Data System (ADS)

    Crossley, S. D.; Mayne, R. G.; Lunning, N. G.; McCoy, T. J.; Greenwood, R. C.; Franchi, I. A.

    2016-08-01

    Melting experiments were performed on the eucrite, NWA 8562, in order to test the partial melt assimilation model of Stannern-trend petrogenesis. Major and trace element data will be applied to the model, and preliminary results appear to fit.

  15. A correlational and experimental examination of reality television viewing and interest in cosmetic surgery.

    PubMed

    Markey, Charlotte N; Markey, Patrick M

    2010-03-01

    Two studies are presented that examine the influence of media messages about cosmetic surgery on youths' interest in altering their own physical appearance. In Study 1, 170 participants (59% female; M age=19.77 years) completed surveys assessing their impression of reality television shows featuring cosmetic surgery, appearance satisfaction, self-esteem, and their interest in cosmetic surgery. Results indicated that participants who reported favorable impressions of reality television shows featuring cosmetic surgery were more likely to indicate interest in pursuing surgery. One hundred and eighty-nine participants (51% female; M age=19.84 years) completed Study 2. Approximately half of the participants were exposed to a television message featuring a surgical make-over; the other half was exposed to a neutral message. Results indicated that participants who watched a television program about cosmetic surgery wanted to alter their own appearance using cosmetic surgery more than did participants who were not exposed to this program.

  16. Safety of Using Matrix Metalloproteinase Inhibitor in Experimental Glaucoma Filtration Surgery

    PubMed Central

    2017-01-01

    We evaluated the safety of matrix metalloproteinase (MMP) inhibitor in experimental glaucoma filtration surgery in an animal model. Fifteen New Zealand white rabbits underwent an experimental trabeculectomy and were randomly allocated into 3 groups according to the adjuvant agent: no treatment group (n = 5), 0.02% mitomycin C (MMC) soaking group (n = 5), and MMP inhibitor (ilomastat) subconjunctival injection group (n = 5). Slit lamp examination with Seidel testing, pachymetry, and specular microscopy was performed preoperatively and postoperatively. The conjunctiva and ciliary body toxicity were evaluated with scores according to the pathologic grading systems. Electron microscopy was used to examine the structural changes in cornea, conjunctiva, and ciliary body. In the ilomastat-treated group, there was no statistically significant change in central corneal thickness preoperatively and at 28 days postoperatively (P = 0.655). There were also no significant changes in specular microscopy findings over the duration of the study in the ilomastat-treated group. The conjunctival toxicity score was 1 in the control group, 1.5 in the ilomastat-treated group, and 2 in the MMC-treated group. When assessing ciliary body toxicity scores, the ilomastat-treated group score was 0.5 and the MMC-treated group score was 1.5. Transmission electron microscopy did not show structural changes in the cornea and ciliary body whereas the structural changes were noticed in MMC group. A single subconjunctival injection of MMP inhibitor during the experimental trabeculectomy showed a less toxic affect in the rabbit cornea, conjunctiva, and ciliary body compared to MMC. PMID:28244295

  17. Petrofabric development during experimental partial melting and recrystallization of a mica-schist analog

    NASA Astrophysics Data System (ADS)

    Almqvist, Bjarne S. G.; Biedermann, Andrea R.; Klonowska, Iwona; Misra, Santanu

    2015-10-01

    Magnetic properties and the anisotropy of magnetic susceptibility (AMS) present promising methods to track mineral orientation and petrofabric in rocks that have undergone partial melting. In order to better understand the source of the magnetic signal in these types of rocks, the interpretation of field observations may be integrated with laboratory experiments, designed to recreate conditions of partial melting. A set of experiments is presented in this study, where synthetic foliated quartz-muscovite aggregates undergo partial melting at 300 MPa hydrostatic confining pressure and 750°C. Magnetic properties and AMS are measured before and after partial melting. Prior to partial melting, the synthetic aggregate shows a compaction-related oblate magnetic fabric, dominated by paramagnetic muscovite that contains small amounts of iron. Post experiment samples show neoblasts that crystallize from incongruent melt reactions. Most notably for the magnetic fabric, the breakdown of muscovite results in growth of secondary phases of Fe-bearing spinel and biotite. Isothermal remanence acquisition and temperature dependence of susceptibility indicate that the spinel is magnetite. The degree of magnetic anisotropy reduces significantly after partial melting, but notably the orientation of the principal axes of susceptibility mimics the AMS of the original quartz-muscovite aggregate. Additionally, the post experiment samples show a relationship between the amount of sample shortening (compaction) and the degree of magnetic anisotropy and susceptibility ellipsoid shape factor. These results suggest that petrofabrics in rocks that undergo partial melting at near hydrostatic pressure conditions may in part be inherited, or mimic, the original petrofabric of a sedimentary or metasedimentary rock.

  18. Experimental validation of A-mode ultrasound acquisition system for computer assisted orthopaedic surgery

    NASA Astrophysics Data System (ADS)

    De Lorenzo, Danilo; De Momi, Elena; Beretta, Elisa; Cerveri, Pietro; Perona, Franco; Ferrigno, Giancarlo

    2009-02-01

    Computer Assisted Orthopaedic Surgery (CAOS) systems improve the results and the standardization of surgical interventions. Anatomical landmarks and bone surface detection is straightforward to either register the surgical space with the pre-operative imaging space and to compute biomechanical parameters for prosthesis alignment. Surface points acquisition increases the intervention invasiveness and can be influenced by the soft tissue layer interposition (7-15mm localization errors). This study is aimed at evaluating the accuracy of a custom-made A-mode ultrasound (US) system for non invasive detection of anatomical landmarks and surfaces. A-mode solutions eliminate the necessity of US images segmentation, offers real-time signal processing and requires less invasive equipment. The system consists in a single transducer US probe optically tracked, a pulser/receiver and an FPGA-based board, which is responsible for logic control command generation and for real-time signal processing and three custom-made board (signal acquisition, blanking and synchronization). We propose a new calibration method of the US system. The experimental validation was then performed measuring the length of known-shape polymethylmethacrylate boxes filled with pure water and acquiring bone surface points on a bovine bone phantom covered with soft-tissue mimicking materials. Measurement errors were computed through MR and CT images acquisitions of the phantom. Points acquisition on bone surface with the US system demonstrated lower errors (1.2mm) than standard pointer acquisition (4.2mm).

  19. Full-scale Experimental Evaluation of Partially Grouted, Minimally Reinforced Concrete Masonry Unit (CMU) Walls Against Blast Demands

    DTIC Science & Technology

    2010-11-30

    research under this program was “to develop blast protection data for concrete building products (e.g. insulated form walls , precast /prestressed panels...AFRL-RX-TY-TR-2011-0025-01 FULL-SCALE EXPERIMENTAL EVALUATION OF PARTIALLY GROUTED, MINIMALLY REINFORCED CONCRETE MASONRY UNIT (CMU) WALLS ...Minimally Reinforced Concrete Masonry Unit (CMU) Walls Against Blast Demands FA8903-08-D-8768-0002 0909999F GOVT F0 QF101000 # Davidson, James S

  20. An experimental Method to Determine Photoelectron Partial Wave Probabilities and the Implications for Quantum Mechanically Complete Experiments

    NASA Astrophysics Data System (ADS)

    Yenen, Orhan

    2003-05-01

    Recent trends in AMO physics is to move from being a passive observer to an active controller of the outcome of quantum phenomena. Full controls of quantum processes require complete information about the quantum system; experiments which measure all the information allowed by quantum mechanics are called "Quantum Mechanically Complete Experiments". For example, when an isolated atom is photoionized, conservation laws limit the allowed partial waves of the photoelectron to a maximum of three. A quantum mechanically complete photoionization experiment then will have to determine all three partial wave probabilities and the two independent phases between the partial waves as a function of ionizing photon energy. From these five parameters all the quantities quantum mechanics allows one to measure can be determined for the "Residual Ion + Photoelectron" system. We have developed experimental methods [1, 2] to determine all three partial wave probabilities of photoelectrons when the residual ion is left in an excited state. Experimentally, Ar atoms are photoionized by circularly polarized synchrotron radiation produced by a unique VUV (vacuum ultraviolet) phase retarder we have installed at the Advanced Light Source (ALS) in Berkeley, CA. We measure the linear and circular polarization of the fine-structure-resolved fluorescent photons from the excited residual ions at specific directions. From the measurements one obtains the relativistic partial wave probabilities of the photoelectron. Our measurements highlight the significance of multielectron processes in photoionization dynamics and provide stringent tests of theory. The results indicate significant spin-dependent relativistic interactions during photoionization. [1] O. Yenen et al., Phys. Rev. Lett. 86, 979 (2001). [2] K. W. McLaughlin et al., Phys. Rev. Lett. 88, 123003 (2002).

  1. Experimental study of the pressure fluctuations in a pump turbine at large partial flow conditions

    NASA Astrophysics Data System (ADS)

    Ran, Hongjuan; Luo, Xianwu; Zhu, Lei; Zhang, Yao; Wang, Xin; Xu, Hongyuan

    2012-11-01

    Frequent shifts of output and operating mode require a pump turbine with excellent stability. Current researches show that large partial flow conditions in pump mode experience positive-slope phenomena with a large head drop. The pressure fluctuation at the positive slope is crucial to the pump turbine unit safety. The operating instabilities at large partial flow conditions for a pump turbine are analyzed. The hydraulic performance of a model pump turbine is tested with the pressure fluctuations measured at unstable operating points near a positive slope in the performance curve. The hydraulic performance tests show that there are two separated positive-slope regions for the pump turbine, with the flow discharge for the first positive slope from 0.85 to 0.91 times that at the maximum efficiency point. The amplitudes of the pressure fluctuations at these unstable large partial flow conditions near the first positive slope are much larger than those at stable operating condtions. A dominant frequency is measured at 0.2 times the impeller rotational frequency in the flow passage near the impeller exit, which is believed to be induced by the rotating stall in the flow passage of the wicket gates. The test results also show hysteresis with pressure fluctuations when the pump turbine is operated near the first positive slope. The hysteresis creates different pressure fluctuations for those operation points even though their flow rates and heads are similar respectively. The pressure fluctuation characteristics at large partial flow conditions obtained by the present study will be helpful for the safe operation of pumped storage units.

  2. Experimental investigations of radial loads induced by partial cavitation with the LH2 Vulcain inducer

    NASA Astrophysics Data System (ADS)

    Goirand, B.; Mertz, A. L.; Joussellin, F.; Rebattet, C.

    Radial forces generated by partial cavitation were investigated both in water and liquid hydrogen (LH2) with the four bladed inducer of the Vulcain liquid hydrogen turbopump. A specific shaft mounted six component balance was developed for inducer water tests, in which force measurements were completed by unsteady pressure measurements and high speed flow visualizations. From water results, a good qualitative agreement with previous experiences was obtained but the influence of blade number was demonstrated. Characteristic frequencies of unsteady cavitation phenomena were identified at different operating points. The force measurements in hydrogen gave promising results about thermodynamics delay, in the scope of establishing transposition rules.

  3. Experimental investigation of gas hydrate formation, plugging and transportability in partially dispersed and water continuous systems

    NASA Astrophysics Data System (ADS)

    Vijayamohan, Prithvi

    As oil/gas subsea fields mature, the amount of water produced increases significantly due to the production methods employed to enhance the recovery of oil. This is true especially in the case of oil reservoirs. This increase in the water hold up increases the risk of hydrate plug formation in the pipelines, thereby resulting in higher inhibition cost strategies. A major industry concern is to reduce the severe safety risks associated with hydrate plug formation, and significantly extending subsea tieback distances by providing a cost effective flow assurance management/safety tool for mature fields. Developing fundamental understanding of the key mechanistic steps towards hydrate plug formation for different multiphase flow conditions is a key challenge to the flow assurance community. Such understanding can ultimately provide new insight and hydrate management guidelines to diminish the safety risks due to hydrate formation and accumulation in deepwater flowlines and facilities. The transportability of hydrates in pipelines is a function of the operating parameters, such as temperature, pressure, fluid mixture velocity, liquid loading, and fluid system characteristics. Specifically, the hydrate formation rate and plugging onset characteristics can be significantly different for water continuous, oil continuous, and partially dispersed systems. The latter is defined as a system containing oil/gas/water, where the water is present both as a free phase and partially dispersed in the oil phase (i.e., entrained water in the oil). Since hydrate formation from oil dispersed in water systems and partially dispersed water systems is an area which is poorly understood, this thesis aims to address some key questions in these systems. Selected experiments have been performed at the University of Tulsa flowloop to study the hydrate formation and plugging characteristics for the partially dispersed water/oil/gas systems as well as systems where the oil is completely dispersed

  4. Prone Accelerated Partial Breast Irradiation After Breast-Conserving Surgery: Five-year Results of 100 Patients

    SciTech Connect

    Formenti, Silvia C.; Hsu, Howard; Fenton-Kerimian, Maria; Roses, Daniel; Guth, Amber; Jozsef, Gabor; Goldberg, Judith D.; DeWyngaert, J. Keith

    2012-11-01

    Purpose: To report the 5-year results of a prospective trial of three-dimensional conformal external beam radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation in the prone position. Methods and Materials: Postmenopausal patients with Stage I breast cancer with nonpalpable tumors <2 cm, negative margins and negative nodes, positive hormone receptors, and no extensive intraductal component were eligible. The trial was offered only after eligible patients had refused to undergo standard whole-breast radiotherapy. Patients were simulated and treated on a dedicated table for prone setup. 3D-CRT was delivered at a dose of 30 Gy in five 6-Gy/day fractions over 10 days with port film verification at each treatment. Rates of ipsilateral breast failure, ipsilateral nodal failure, contralateral breast failure, and distant failure were estimated using the cumulative incidence method. Rates of disease-free, overall, and cancer-specific survival were recorded. Results: One hundred patients were enrolled in this institutional review board-approved prospective trial, one with bilateral breast cancer. One patient withdrew consent after simulation, and another patient elected to interrupt radiotherapy after receiving two treatments. Ninety-eight patients were evaluable for toxicity, and, in 1 case, both breasts were treated with partial breast irradiation. Median patient age was 68 years (range, 53-88 years); in 55% of patients the tumor size was <1 cm. All patients had hormone receptor-positive cancers: 87% of patients underwent adjuvant antihormone therapy. At a median follow-up of 64 months (range, 2-125 months), there was one local recurrence (1% ipsilateral breast failure) and one contralateral breast cancer (1% contralateral breast failure). There were no deaths due to breast cancer by 5 years. Grade 3 late toxicities occurred in 2 patients (one breast edema, one transient breast pain). Cosmesis was rated good/excellent in 89% of patients with at least 36

  5. Experimental derivation of nepheline syenite and phonolite liquids by partial melting of upper mantle peridotites

    NASA Astrophysics Data System (ADS)

    Laporte, Didier; Lambart, Sarah; Schiano, Pierre; Ottolini, Luisa

    2014-10-01

    Piston-cylinder experiments were performed to characterize the composition of liquids formed at very low degrees of melting of two fertile lherzolite compositions with 430 ppm and 910 ppm K2O at 1 and 1.3 GPa. We used the microdike technique (Laporte et al., 2004) to extract the liquid phase from the partially molten peridotite, allowing us to analyze liquid compositions at degrees of melting F down to 0.9%. At 1.3 GPa, the liquid is in equilibrium with olivine + orthopyroxene + clinopyroxene + spinel in all the experiments; at 1 GPa, plagioclase is present in addition to these four mineral phases up to about 5% of melting (T≈1240 °C). Important variations of liquid compositions are observed with decreasing temperature, including strong increases in SiO2, Na2O, K2O, and Al2O3 concentrations, and decreases in MgO, FeO, and CaO concentrations. The most extreme liquid compositions are phonolites with 57% SiO2, 20-22% Al2O3, Na2O + K2O up to 14%, and concentrations of MgO, FeO, and CaO as low as 2-3%. Reversal experiments confirm that low-degree melts of a fertile lherzolite have phonolitic compositions, and pMELTS calculations show that the amount of phonolite liquid generated at 1.2 GPa increases from 0.3% in a source with 100 ppm K2O to 3% in a source with 2000 ppm K2O. The enrichment in silica and alkalis with decreasing melt fraction is coupled with an increase of the degree of melt polymerization, which has important consequences for the partitioning of minor and trace elements. Thus Ti4+ in our experiments and, by analogy with Ti4+, other highly charged cations, and rare earth elements become less incompatible near the peridotite solidus. Our study brings a strong support to the hypothesis that phonolitic lavas or their plutonic equivalents (nepheline syenites) may be produced directly by partial melting of upper mantle rock-types at moderate pressures (1-1.5 GPa), especially where large domains of the subcontinental lithospheric mantle has been enriched in

  6. Experimental demonstration of optimal universal asymmetric quantum cloning of polarization states of single photons by partial symmetrization

    SciTech Connect

    Cernoch, Antonin; Soubusta, Jan; Celechovska, Lucie; Dusek, Miloslav; Fiurasek, Jaromir

    2009-12-15

    We report on experimental implementation of the optimal universal asymmetric 1->2 quantum cloning machine for qubits encoded into polarization states of single photons. Our linear-optical machine performs asymmetric cloning by partially symmetrizing the input polarization state of signal photon and a blank copy idler photon prepared in a maximally mixed state. We show that the employed method of measurement of mean clone fidelities exhibits strong resilience to imperfect calibration of the relative efficiencies of single-photon detectors used in the experiment. Reliable characterization of the quantum cloner is thus possible even when precise detector calibration is difficult to achieve.

  7. Experimental Verification of the Kruskal-Shafranov Stability Limit in Line-Tied Partial Toroidal Plasmas

    SciTech Connect

    Oz, E.; Myers, C. E.; Yamada, M.; Ji, H.; Kulsrud, R. M.; Xie, J.

    2011-07-19

    The stability properties of partial toroidal flux ropes are studied in detail in the laboratory, motivated by ubiquitous arched magnetic structures found on the solar surface. The flux ropes studied here are magnetized arc discharges formed between two electrodes in the Magnetic Reconnection Experiment (MRX) [Yamada et al., Phys. Plasmas, 4, 1936 (1997)]. The three dimensional evolution of these flux ropes is monitored by a fast visible light framing camera, while their magnetic structure is measured by a variety of internal magnetic probes. The flux ropes are consistently observed to undergo large-scale oscillations as a result of an external kink instability. Using detailed scans of the plasma current, the guide field strength, and the length of the flux rope, we show that the threshold for kink stability is governed by the Kruskal-Shafranov limit for a flux rope that is held fixed at both ends (i.e., qa = 1).

  8. Cost comparison of open approach, transoral laser microsurgery and transoral robotic surgery for partial and total laryngectomies.

    PubMed

    Dombrée, Manon; Crott, Ralph; Lawson, Georges; Janne, Pascal; Castiaux, Annick; Krug, Bruno

    2014-10-01

    Activity-based costing is used to give a better insight into the actual cost structure of open, transoral laser microsurgery (TLM) and transoral robotic surgery (TORS) supraglottic and total laryngectomies. Cost data were obtained from hospital administration, personnel and vendor structured interviews. A process map identified 17 activities, to which the detailed cost data are related. One-way sensitivity analyses on the patient throughput, the cost of the equipment or operative times were performed. The total cost for supraglottic open (135-203 min), TLM (110-210 min) and TORS (35-130 min) approaches were 3,349 euro (3,193-3,499 euro), 3,461 euro (3,207-3,664 euro) and 5,650 euro (4,297-5,974 euro), respectively. For total laryngectomy, the overall cost were 3,581 euro (3,215-3,846 euro) for open and 6,767 euro (6,418-7,389 euro) for TORS. TORS cost is mostly influenced by equipment (54%) where the other procedures are predominantly determined by personnel cost (about 45%). Even when we doubled the yearly case-load, used the shortest operative times or a calculation without robot equipment costs we did not reach cost equivalence. TORS is more expensive than standard approaches and mainly influenced by purchase and maintenance costs and the use of proprietary instruments. Further trials on long-term outcomes and costs following TORS are needed to evaluate its cost-effectiveness.

  9. Mini-flank supra-12th rib incision for open partial nephrectomy for renal tumor with RENAL nephrometry score ≥10: an innovation of traditional open surgery.

    PubMed

    Wang, Hang; Sun, Li-an; Wang, Yiwei; Xiang, Zhuoyi; Zhou, Lin; Guo, Jianming; Wang, Guomin

    2015-04-01

    The skill of supra-12th rib mini-flank approach for open partial nephrectomy (MI-OPN) provides an advanced operative method for renal tumor. Compared with laparoscopic and robotic surgery, it may be a feasible selection for the complex renal tumors. We describe our techniques and results of MI-OPN in complex renal tumors with high RENAL nephrometry score (RENAL nephrometry score ≥10). Fifty-five patients diagnosed with renal tumors between January 2009 and July 2013 were included in this study. Eligibility criteria comprised of patients with complex renal tumor (RENAL score ≥10) being candidates for partial nephrectomy (PN). All patients received MI-OPN and all surgeries were performed by a single urologist. The preoperative workup comprised of medical history, physical examination, and routine laboratory tests. Serum creatinine was recorded preoperatively and 2 to 3 months after operation. Operative time, ischemia time, blood loss, operative and postoperative complications, renal function, and pathology parameters were recorded. MI-OPN was successfully performed in all cases. Mean tumor size was 4.7 cm (range: 2.5-8.1). Mean warm ischemia time was 28.1 minutes (range: 21-39), mean operative time was 105 minutes (range: 70-150) and mean estimated blood loss was 68 mL (range: 10-400). Mean postoperative hospital stay was 6.5 days (range: 5-12). Postoperative complications were found in 3 patients (5.5%). The mean pre- and postoperative serum creatinine levels were 76.2 μmol/L (range: 47-132) and 87.1 μmol/L (range: 61-189) with significant difference (P = 0.004). The mean pre- and postoperative estimated glomerular filtration rate (eGFR) were 91.5 (range: 34-133) and 82.5 (range: 22-126.5), respectively with significant difference (P = 0.024). In an average follow-up of 19.9 months (range: 8-50), no local recurrence or systemic progression occurred. In conclusion, MI-OPN can combine the benefits of both minimal invasive and traditional open

  10. [Urodynamics of upper urinary tracts after intestinal plastic surgery on urinary bladder (experimental study)].

    PubMed

    Loran, O B; Mudraia, I S; David'iants, A A; Zaĭtsev, A V

    1999-01-01

    In dog experiments, the urinary bladder was replaced for an isolated intestinal segment to test upper urinary tract function as regards configuration of the established urine reservoir early and late after the surgery. Intestinal plastic surgery of the bladder changes parameters of ureteral function in unchanged potential reserve of ureteral contraction. Postileocystoplasty urodynamics of the upper urinary tracts is characterized by lowering of intraureteral pressure, decreased amplitude of ureteral contractions, enhanced tonicity and motility. Plastic replacement of the bladder with isolated intestinal segment is not contraindicated in the solitary kidney.

  11. From Guided Surgery to Final Prosthesis with a Fully Digital Procedure: A Prospective Clinical Study on 15 Partially Edentulous Patients

    PubMed Central

    2016-01-01

    Scope. To demonstrate guided implant placement and the application of fixed, implant-supported prosthetic restorations with a fully digital workflow. Methods. Over a 2-year period, all patients with partial edentulism of the posterior maxilla, in need of fixed implant-supported prostheses, were considered for inclusion in this study. The protocol required intraoral scanning and cone beam computed tomography (CBCT), the superimposition of dental-gingival information on bone anatomy, surgical planning, 3D-printed teeth-supported surgical templates, and modelling and milling of polymethylmethacrylate (PMMA) temporaries for immediate loading. After 3 months, final optical impression was taken and milled zirconia frameworks and 3D-printed models were fabricated. The frameworks were veneered with ceramic and delivered to the patients. Results. Fifteen patients were selected for this study. The surgical templates were stable. Thirty implants were placed (BTK Safe®, BTK, Vicenza, Italy) and immediately loaded with PMMA temporaries. After 3 months, the temporaries were replaced by the final restorations in zirconia-ceramic, fabricated with a fully digital process. At 6 months, none of the patients reported any biological or functional problems with the implant-supported prostheses. Conclusions. The present procedure for fully digital planning of implants and short-span fixed implant-supported restorations has been shown to be reliable. Further studies are needed to validate these results. PMID:27493665

  12. Exogenous collagen cross-linking recovers tendon functional integrity in an experimental model of partial tear.

    PubMed

    Fessel, Gion; Wernli, Jeremy; Li, Yufei; Gerber, Christian; Snedeker, Jess G

    2012-06-01

    We investigated the hypothesis that exogenous collagen cross-linking can augment intact regions of tendon to mitigate mechanical propagation of partial tears. We first screened the low toxicity collagen cross-linkers genipin, methylglyoxal and ultra-violet (UV) light for their ability to augment tendon stiffness and failure load in rat tail tendon fascicles (RTTF). We then investigated cross-linking effects in load bearing equine superficial digital flexor tendons (SDFT). Data indicated that all three cross-linking agents augmented RTTF mechanical properties but reduced native viscoelasticity. In contrast to effects observed in fascicles, methylglyoxal treatment of SDFT detrimentally affected tendon mechanical integrity, and in the case of UV did not alter tendon mechanics. As in the RTTF experiments, genipin cross-linking of SDFT resulted in increased stiffness, higher failure loads and reduced viscoelasticity. Based on this result we assessed the efficacy of genipin in arresting tendon tear propagation in cyclic loading to failure. Genipin cross-linking secondary to a mid-substance biopsy-punch significantly reduced tissue strains, increased elastic modulus and increased resistance to fatigue failure. We conclude that genipin cross-linking of injured tendons holds potential for arresting tendon tear progression, and that implications of the treatment on matrix remodeling in living tendons should now be investigated.

  13. Effect of partial liquid ventilation on pulmonary vascular permeability and edema after experimental acute lung injury.

    PubMed

    Lange, N R; Kozlowski, J K; Gust, R; Shapiro, S D; Schuster, D P

    2000-07-01

    We evaluated the effects of partial liquid ventilation (PLV) with two different dosages of the perfluorocarbon LiquiVent (perflubron) on pulmonary vascular permeability and edema formation after oleic acid (OA)-induced acute lung injury in dogs. We used imaging with positron emission tomography to measure fractional pulmonary blood flow, lung water concentration (LWC), and the pulmonary transcapillary escape rate (PTCER) of (68)Ga-labeled transferrin at 5 and 21 h after lung injury in five dogs undergoing conventional mechanical ventilation (CMV), five dogs undergoing low-dose PLV (perflubron at 10 ml/kg), and four dogs undergoing high dose PLV (perflubron at 30 ml/kg). A positive end-expiratory pressure of 7.5 cm H(2)O was used in all dogs. After OA (0.08 ml/kg)- induced lung injury, there were no significant differences or trends for PTCER or LWC at any time when the PLV groups were compared with the CMV group. However, lung tissue myeloperoxidase activity was significantly lower in the combined PLV group than in the CMV group (p = 0.016). We conclude that after OA-induced lung injury, the addition of PLV to CMV does not directly attenuate pulmonary vascular leak or lung water accumulation. Rather, the benefits of such treatment may be due to modifications of the inflammatory response.

  14. Experimental determination of carbonation rate in Portland cement at 25°C and relatively high CO2 partial pressure

    NASA Astrophysics Data System (ADS)

    Hernández-Rodríguez, Ana; Montegrossi, Giordano; Huet, Bruno; Virgili, Giorgio; Orlando, Andrea; Vaselli, Orlando; Marini, Luigi

    2016-04-01

    The aim of this work is to study the alteration of Portland class G Cement at ambient temperature under a relatively high CO2 partial pressure through suitably designed laboratory experiments, in which cement hydration and carbonation are taken into account separately. First, the hydration process was carried out for 28 days to identify and quantify the hydrated solid phases formed. After the completion of hydration, accompanied by partial carbonation under atmospheric conditions, the carbonation process was investigated in a stirred micro-reactor (Parr instrument) with crushed cement samples under 10 bar or more of pure CO2(g) and MilliQ water adopting different reaction times. The reaction time was varied to constrain the reaction kinetics of the carbonation process and to investigate the evolution of secondary solid phases. Chemical and mineralogical analyses (calcimetry, chemical composition, SEM and X-ray Powder Diffraction) were carried out to characterize the secondary minerals formed during cement hydration and carbonation. Water analyses were also performed at the end of each experimental run to measure the concentrations of relevant solutes. The specific surface area of hydrated cement was measured by means of the BET method to obtain the rates of cement carbonation. Experimental outcomes were simulated by means of the PhreeqC software package. The obtained results are of interest to understand the comparatively fast cement alteration in CO2 production wells with damaged casing.

  15. Experimental evidence for melt partitioning between olivine and orthopyroxene in partially molten harzburgite

    NASA Astrophysics Data System (ADS)

    Miller, Kevin J.; Zhu, Wen-lu; Montési, Laurent G. J.; Gaetani, Glenn A.; Le Roux, Véronique; Xiao, Xianghui

    2016-08-01

    Observations of dunite channels in ophiolites and uranium series disequilibria in mid-ocean ridge basalt suggest that melt transport in the upper mantle beneath mid-ocean ridges is strongly channelized. We present experimental evidence that spatial variations in mineralogy can also focus melt on the grain scale. This lithologic melt partitioning, which results from differences in the interfacial energies associated with olivine-melt and orthopyroxene-melt boundaries, may complement other melt focusing mechanisms in the upper mantle such as mechanical shear and pyroxene dissolution. We document here lithologic melt partitioning in olivine-/orthopyroxene-basaltic melt samples containing nominal olivine to orthopyroxene ratio of 3 to 2 and melt fractions of 0.02 to 0.20. Experimental samples were imaged using synchrotron-based X-ray microcomputed tomography at a resolution of 700 nm per voxel. By analyzing the local melt fraction distributions associated with olivine and orthopyroxene grains in each sample, we found that the melt partitioning coefficient, i.e., the ratio of melt fraction around olivine to that around orthopyroxene grains, varies between 1.1 and 1.6. The permeability and electrical conductivity of our digital samples were estimated using numerical models and compared to those of samples containing only olivine and basaltic melt. Our results suggest that lithologic melt partitioning and preferential localization of melt around olivine grains might play a role in melt focusing, potentially enhancing average melt ascent velocities.

  16. Experimental test of theory for the stability of partially saturated vertical cut slopes

    USGS Publications Warehouse

    Morse, Michael M.; Lu, N.; Wayllace, Alexandra; Godt, Jonathan W.; Take, W.A.

    2014-01-01

    This paper extends Culmann's vertical-cut analysis to unsaturated soils. To test the extended theory, unsaturated sand was compacted to a uniform porosity and moisture content in a laboratory apparatus. A sliding door that extended the height of the free face of the slope was lowered until the vertical cut failed. Digital images of the slope cross section and upper surface were acquired concurrently. A recently developed particle image velocimetry (PIV) tool was used to quantify soil displacement. The PIV analysis showed strain localization at varying distances from the sliding door prior to failure. The areas of localized strain were coincident with the location of the slope crest after failure. Shear-strength and soil-water-characteristic parameters of the sand were independently tested for use in extended analyses of the vertical-cut stability and of the failure plane angle. Experimental failure heights were within 22.3% of the heights predicted using the extended theory.

  17. Partial Sleep Restriction Activates Immune Response-Related Gene Expression Pathways: Experimental and Epidemiological Studies in Humans

    PubMed Central

    Rantanen, Ville; Kronholm, Erkki; Surakka, Ida; van Leeuwen, Wessel M. A.; Lehto, Maili; Matikainen, Sampsa; Ripatti, Samuli; Härmä, Mikko; Sallinen, Mikael; Salomaa, Veikko; Jauhiainen, Matti; Alenius, Harri; Paunio, Tiina; Porkka-Heiskanen, Tarja

    2013-01-01

    Epidemiological studies have shown that short or insufficient sleep is associated with increased risk for metabolic diseases and mortality. To elucidate mechanisms behind this connection, we aimed to identify genes and pathways affected by experimentally induced, partial sleep restriction and to verify their connection to insufficient sleep at population level. The experimental design simulated sleep restriction during a working week: sleep of healthy men (N = 9) was restricted to 4 h/night for five nights. The control subjects (N = 4) spent 8 h/night in bed. Leukocyte RNA expression was analyzed at baseline, after sleep restriction, and after recovery using whole genome microarrays complemented with pathway and transcription factor analysis. Expression levels of the ten most up-regulated and ten most down-regulated transcripts were correlated with subjective assessment of insufficient sleep in a population cohort (N = 472). Experimental sleep restriction altered the expression of 117 genes. Eight of the 25 most up-regulated transcripts were related to immune function. Accordingly, fifteen of the 25 most up-regulated Gene Ontology pathways were also related to immune function, including those for B cell activation, interleukin 8 production, and NF-κB signaling (P<0.005). Of the ten most up-regulated genes, expression of STX16 correlated negatively with self-reported insufficient sleep in a population sample, while three other genes showed tendency for positive correlation. Of the ten most down-regulated genes, TBX21 and LGR6 correlated negatively and TGFBR3 positively with insufficient sleep. Partial sleep restriction affects the regulation of signaling pathways related to the immune system. Some of these changes appear to be long-lasting and may at least partly explain how prolonged sleep restriction can contribute to inflammation-associated pathological states, such as cardiometabolic diseases. PMID:24194869

  18. Experimental test of MR fluid based tactile device for minimally invasive surgery

    NASA Astrophysics Data System (ADS)

    Oh, Jong-Seok; Kim, Jin-Kyu; Choi, Seung-Bok

    2013-04-01

    Recently, it is very popular in modern medical industry to adopt robotic technology such as robotic minimally invasive surgery (RMIS). Compared with open surgery, the RMIS needs the robot to perform surgery through the usage of long surgical instruments that are inserted through incision points. This causes the surgeon not to feel viscosity and stiffness of the tissue or organ. So, for the tactile recognition of human organ in RMIS, this work proposes a novel tactile device that incorporates with magnetorheological (MR) fluid. The MR fluid is fully contained by diaphragm and several pins. By applying different magnetic field, the operator can feel different force from the proposed tactile device. In order to generate required force from the device, the repulsive force of human body is firstly measured as reference data and an appropriate size of tactile device is designed. Pins attached with the diaphragm are controlled by shape-memory-alloy (SMA). Thus, the proposed tactile device can realize repulsive force and shape of organ. It has been demonstrated via experiment whether the measured force can be achieved by applying proper control input current. In addition, psychophysical experiments are conducted to evaluate performance on the tactile rendering of the proposed tactile device. From these results, the practical feasibility of the tactile device is verified.

  19. High-intensity focused ultrasound: advances in technology and experimental trials support enhanced utility of focused ultrasound surgery in oncology

    PubMed Central

    Malietzis, G; Monzon, L; Hand, J; Wasan, H; Leen, E; Abel, M; Muhammad, A; Abel, P

    2013-01-01

    High-intensity focused ultrasound (HIFU) is a rapidly maturing technology with diverse clinical applications. In the field of oncology, the use of HIFU to non-invasively cause tissue necrosis in a defined target, a technique known as focused ultrasound surgery (FUS), has considerable potential for tumour ablation. In this article, we outline the development and underlying principles of HIFU, overview the limitations and commercially available equipment for FUS, then summarise some of the recent technological advances and experimental clinical trials that we predict will have a positive impact on extending the role of FUS in cancer therapy. PMID:23403455

  20. The risk of biomaterial-associated infection after revision surgery due to an experimental primary implant infection.

    PubMed

    Engelsman, Anton F; Saldarriaga-Fernandez, Isabel C; Nejadnik, M Reza; van Dam, Gooitzen M; Francis, Kevin P; Ploeg, Rutger J; Busscher, Henk J; van der Mei, Henny C

    2010-10-01

    The fate of secondary biomaterial implants was determined by bio-optical imaging and plate counting, after antibiotic treatment of biomaterials-associated-infection (BAI) and surgical removal of an experimentally infected, primary implant. All primary implants and tissue samples from control mice showed bioluminescence and were culture-positive. In an antibiotic treated group, no bioluminescence was detected and only 20% of all primary implants and no tissue samples were culture-positive. After revision surgery, bioluminescence was detected in all control mice. All the implants and 80% of all tissue samples were culture-positive. In contrast, in the antibiotic treated group, 17% of all secondary implants and 33% of all tissue samples were culture-positive, despite antibiotic treatment. The study illustrates that due to the BAI of a primary implant, the infection risk of biomaterial implants is higher in revision surgery than in primary surgery, emphasizing the need for full clearance of the infection, as well as from surrounding tissues prior to implantation of a secondary implant.

  1. The all-ceramic, inlay supported fixed partial denture. Part 3. Experimental approach for validating the finite element analysis.

    PubMed

    Thompson, M C; Field, C J; Swain, M V

    2012-03-01

    In a previous study, the authors used a finite element analysis (FEA) to evaluate the stresses developed during the loading of an all-ceramic, inlay supported fixed partial denture and compared it with the more traditional full crown supported prosthesis. To date there has been little research into correlating the responses of the numerical model against physical mechanical tests; such validation analysis is crucial if the results from the FEA are to be confidently relied upon. This study reports on the experimental methods used to compare with the FEA and thereby to validate the predictive fracture behaviour of the numerical model. This study also outlines the methods for manufacture and testing of the ceramic structure along with observations of the fracture tests. In addition the procedure used for developing the FEA model for the test system is outlined.

  2. A petrologic, thermodynamic and experimental study of brachinites: Partial melt residues of an R chondrite-like precursor

    NASA Astrophysics Data System (ADS)

    Gardner-Vandy, Kathryn G.; Lauretta, Dante S.; McCoy, Timothy J.

    2013-12-01

    The primitive achondrites provide a window into the initial melting of asteroids in the early solar system. The brachinites are olivine-dominated meteorites with a recrystallized texture that we and others interpret as evidence of partial melting and melt removal on the brachinite parent body. We present a petrologic, thermodynamic and experimental study of the brachinites to evaluate the conditions under which they formed and test our hypothesis that the precursor material to the brachinites was FeO-rich compared to the precursors of other primitive achondrites. Petrologic analysis of six brachinites (Brachina, Allan Hills (ALH) 84025, Hughes 026, Elephant Moraine (EET) 99402, Northwest Africa (NWA) 3151, and NWA 4969) and one brachinite-like achondrite (NWA 5400) shows that they are meteorites with recrystallized texture that are enriched in olivine (⩾80 vol.%) and depleted in other minerals with respect to a chondritic mineralogy. Silicates in the brachinites are FeO-rich (Fa32-36). Brachinite-like achondrite Northwest Africa 5400 is similar in mineralogy and texture to the brachinites but with a slightly lower FeO-content (Fa30). Thermodynamic calculations yield equilibration temperatures above the Fe,Ni-FeS cotectic temperature (∼950 °C) for all meteorites studied here and temperatures above the silicate eutectic (∼1050 °C) for all but two. Brachina formed at an fO2 of ∼IW, and the other brachinites and NWA 5400 formed at ∼IW - 1. All the meteorites show great evidence of formation by partial melting having approximately chondritic to depleted chondritic mineralogies, equilibrated mineral compositions, and recrystallized textures, and having reached temperatures above that required for melt generation. In an attempt to simulate the formation of the brachinite meteorites, we performed one-atmosphere, gas-mixing partial melting experiments of R4 chondrite LaPaz Ice Field 03639. Experiments at 1250 °C and an oxygen fugacity of IW - 1 produce residual

  3. Partial reverse of the TCA cycle is enhanced in Taenia crassiceps experimental neurocysticercosis after in vivo treatment with anthelminthic drugs.

    PubMed

    de Almeida Leandro, Leticia; Fraga, Carolina Miguel; de Souza Lino, Ruy; Vinaud, Marina Clare

    2014-04-01

    Neurocysticercosis (NCC) is the most common helminthic infection and neglected disease of the central nervous system. It is the leading cause of acquired epilepsy and seizures worldwide. Therefore, to study this important neglected disease, it is important to use experimental models. There is no report in the literature on how the parasite's metabolism reacts to antihelminthic treatment when it is still within the central nervous system of the host. Therefore, the aim of this study was to investigate the energetic metabolism of cysticerci experimentally inoculated in the encephala of BALB/c mice after treatment with low dosages (not sufficient to kill the parasite) of albendazole (ABDZ) and praziquantel (PZQ). BALB/c mice were intracranially inoculated with Taenia crassiceps cysticerci and, after 30 days, received treatment with low dosages of ABDZ and PZQ. After 24 h of treatment, the mice were euthanized, and the cysticerci were removed and analyzed through high-performance liquid chromatography (HPLC) to quantify the organic acids related to the energetic metabolism of the parasite. The partial reverse of the TCA cycle was enhanced by the ABDZ and PZQ treatments both with the higher dosage, as the organic acids of this pathway were significantly increased when compared to the control group and to the other dosages. In conclusion, it was possible to detect the increase of this pathway in the parasites that were exposed to low dosages of ABDZ and PZQ, as it is a mechanism that would amplify the energy production in a hostile environment.

  4. Monte Carlo simulations to optimize experimental dosimetry of narrow beams used in Gamma Knife radio-surgery

    NASA Astrophysics Data System (ADS)

    Lymperopoulou, G.; Petrokokkinos, L.; Papagiannis, P.; Steiner, M.; Spevacek, V.; Semnicka, J.; Dvorak, P.; Seimenis, I.

    2007-09-01

    The Leksell Gamma Knife is a stereotactic radio-surgery unit for the treatment of small volumes (on the order of 25 mm 3) that employs a hemispherical configuration of 201 60Co sources and appropriate configurations of collimation to form beams of 4, 8, 14 and 18 mm nominal diameter at the Unit Center Point (UCP). Although Monte Carlo (MC) simulation is well suited for narrow-beam dosimetry, experimental dosimetry is required at least for acceptance testing and quality assurance purposes. Besides other drawbacks of conventional point dosimeters, the main problems associated with narrow-beam dosimetry in stereotactic applications are accurate positioning and volume averaging. In this work, MCNPX and EGSnrc MC simulation dosimetry results for a Gamma Knife unit are benchmarked through their comparison to treatment planning software calculations based on radio-chromic film measurements. Then, MC dosimetry results are utilized to optimize the only three-dimensional experimental dosimetry method available; the polymer gel-Magnetic Resonance Imaging (MRI) method. MC results are used to select the spatial resolution in the imaging session of the irradiated gels and validate a mathematical tool for the localization of the UCP in the three-dimensional experimental dosimetry data acquired. Experimental results are compared with corresponding MC calculations and shown capable to provide accurate dosimetry, free of volume averaging and positioning uncertainties.

  5. Experimental studies on the usage possibilities of the Nd:YAG laser in the cataract surgery

    NASA Astrophysics Data System (ADS)

    Yu, Xiaomin; Ma, Nina; Li, Jiaze

    2005-01-01

    The investigations of used pulsed Q-switched neodymium:YAG laser induced plasma and shock wave during experimental lenses emulsification were presented. The formation and propagation of plasma and shock wave created by the high powered Nd:YAG laser pulses with a titanium target were imaged through optical multiple analysis, and the pressure of shock wave was calculated. The results of shock wave interacting with the lenses material were observed. The lenses, simulated at different hardness, were placed in containers filled with Ringer's solution. The experimental results are promising and show that the Nd:YAG laser can be used for human lens emulsification.

  6. An ex vivo feasibility experimental study on targeted cell surgery by high intensity focused ultrasound

    NASA Astrophysics Data System (ADS)

    Wang, Zhi Biao; Wu, Junru; Fang, Liao Qiong; Wang, Hua; Li, Fa Qi; Tian, Yun Bo; Gong, Xiao Bo; Zhang, Hong; Zhang, Lian; Feng, Ruo

    2012-10-01

    High intensity focused ultrasound (HIFU) has become a new noninvasive surgical modality in medicine. A portion of tissue seated inside a patient's body may experience coagulative necrosis after a few seconds of insonification by high intensity focused ultrasound (US) generated by an extracorporeal focusing US transducer. The region of tissue affected by coagulative necrosis (CN) usually has an ellipsoidal shape when the thermal effect due to US absorption plays the dominant role. Its long and short axes are parallel and perpendicular to the US propagation direction respectively. It was shown by ex vivo experiments that the dimension of the short and long axes of the tissue which experiences CN can be as small as 50 μm and 250 μm respectively after one second exposure of US pulse (the spatial and pulse average acoustic power is on the order of tens of Watts and the local acoustic spatial and temporal pulse averaged intensity is on the order of 3 × 104 W/cm2) generated by a 1.6 MHz HIFU transducer of 12 cm diameter and 11 cm geometric focal length (f-number = 0.92). The numbers of cells which suffered CN were estimated to be on the order of 40. This result suggests that HIFU is able to interact with tens of cells at/near its focal zone while keeping the neighboring cells minimally affected, and thus the targeted cell surgery may be achievable.

  7. Time-dependency of improvements in arterial oxygenation during partial liquid ventilation in experimental acute respiratory distress syndrome

    PubMed Central

    Max, Martin; Kuhlen, Ralf; Dembinski, Rolf; Rossaint, Rolf

    2000-01-01

    Background: The mechanisms by which partial liquid ventilation (PLV) can improve gas exchange in acute lung injury are still unclear. Therefore, we examined the time- and dose-dependency of the improvements in arterial oxygen tension (PaO2) due to PLV in eight pigs with experimental lung injury, in order to discriminate increases due to oxygen dissolved in perfluorocarbon before its intrapulmonary instillation from a persistent diffusion of the respiratory gas through the liquid column. Results: Application of four sequential doses of perfluorocarbon resulted in a dose-dependent increase in PaO2. Comparison of measurements 5 and 30 min after instillation of each dose revealed a time-dependent decrease in PaO2 for doses that approximated the functional residual capacity of the animals. Conclusion: Although oxygen dissolved in perfluorocarbon at the onset of PLV can cause a short-term improvement in arterial oxygenation, diffusion of oxygen through the liquid may not be sufficient to maintain the initially observed increase in PaO2. PMID:11056747

  8. Experimental investigation of transport of discrete solids with surge flows in a 10.0 cm diameter partially filled pipe

    NASA Astrophysics Data System (ADS)

    Mahajan, B. M.

    1982-01-01

    The transport of discrete solids with surge flows in a partially filled slightly pitched horizontal pipe was investigated. The experimental apparatus, instrumentation, and procedures are described. The experiments were conducted using a cylindrical solid in a 10.0 cm (4 in) diameter pipe. The water surge flows were obtained by discharging different volumes of water into the pipe from a falling head open container which simulated a water closet. Flow induced solid velocities and stream depth histories at various locations along the length of the pipe were measured. The effects of water volume used, pipe slope, and size of the solid on the solid velocities were examined. Solid velocities were compared with the maximum water velocities estimated from the stream depth histories. Also, the distance traversed by the solids in the pipe were measured for those cases in which the solids did not clear the pipe. The solid velocity increased with an increase in water volume used, a decrease in the size of the solid, and an increase in the pipe slope. The solid velocity in the initial reach of the pipe was less than the maximum water velocity; and the solid velocity approaches the maximum water velocity as the solid traveled downstream, except for some experiments with small water volumes.

  9. Experimental assessment of energy requirements and tool tip visibility for photoacoustic-guided endonasal surgery

    NASA Astrophysics Data System (ADS)

    Lediju Bell, Muyinatu A.; Dagle, Alicia B.; Kazanzides, Peter; Boctor, Emad M.

    2016-03-01

    Endonasal transsphenoidal surgery is an effective approach for pituitary adenoma resection, yet it poses the serious risk of internal carotid artery injury. We propose to visualize these carotid arteries, which are hidden by bone, with an optical fiber attached to a surgical tool and a transcranial ultrasound probe placed on the patient's temple (i.e. intraoperative photoacoustic imaging). To investigate energy requirements for vessel visualization, experiments were conducted with a phantom containing ex vivo sheep brain, ex vivo bovine blood, and 0.5-2.5 mm thick human cadaveric skull specimens. Photoacoustic images were acquired with 1.2-9.3 mJ laser energy, and the resulting vessel contrast was measured at each energy level. The distal vessel boundary was difficult to distinguish at the chosen contrast threshold for visibility (4.5 dB), which was used to determine the minimum energies for vessel visualization. The blood vessel was successfully visualized in the presence of the 0-2.0 mm thick sphenoid and temporal bones with up to 19.2 dB contrast. The minimum energy required ranged from 1.2-5.0 mJ, 4.2-5.9 mJ, and 4.6-5.2 mJ for the 1.0 temporal and 0-1.5 mm sphenoid bones, 1.5 mm temporal and 0-0.5 mm sphenoid bones, and 2.0 mm temporal and 0-0.5 mm sphenoid bones, respectively, which corresponds to a fluence range of 4-21 mJ/cm2. These results hold promise for vessel visualization within safety limits. In a separate experiment, a mock tool tip was placed, providing satisfactory preliminary evidence that surgical tool tips can be visualized simultaneously with blood vessels.

  10. Magnetic and elastic wave anisotropy in partially molten rocks: insight from experimental melting of synthetic quartz-mica schist (Invited)

    NASA Astrophysics Data System (ADS)

    Almqvist, B.; Misra, S.; Biedermann, A. R.; Mainprice, D.

    2013-12-01

    We studied the magnetic and elastic wave speed anisotropy of a synthetically prepared quartz-mica schist, prior to, during and after experimental melting. The synthetic rock was manufactured from a mixture of powders with equal volumes of quartz and muscovite. The powders were initially compacted with 200 MPa uniaxial stress at room temperature and sealed in a stainless steel canister. Subsequently the sealed canister was isostatically pressed at 180 MPa and 580 °C for 24 hours. This produced a solid medium with ~25 % porosity. Mica developed a preferred grain-shape alignment due to the initial compaction with differential load, where mica flakes tend to orient perpendicular to the applied stress and hence define a synthetic foliation plane. In the last stage we used a Paterson gas-medium apparatus, to pressurize and heat the specimens up to 300 MPa and 750 °C for a six hour duration. This stage initially compacted the rock, followed by generation of melt, and finally crystallization of new minerals from the melt. Elastic wave speed measurements were performed in situ at pressure and temperature, with a transducer assembly mounted next to the sample. Magnetic measurements were performed before and after the partial melt experiments. Anisotropy was measured in low- and high-field, using a susceptibility bridge and torsion magnetometer, respectively. Additionally we performed measurements of hysteresis, isothermal remanent magnetization (IRM) and susceptibility as a function of temperature, to investigate the magnetic properties of the rock. The elastic wave speed, before the melting-stage of the experiment, exhibits a distinct anisotropy with velocities parallel to the foliation being about 15 % higher than normal to the foliation plane. Measurements of the magnetic anisotropy in the bulk sample show that anisotropy is originating from the preferred orientation of muscovite, with a prominent flattening fabric. In contrast, specimens that underwent partial melting

  11. [Results of a morphological study of the experimental use of polyglycolide fiber explants in the surgery of retinal detachment].

    PubMed

    Kiseleva, O A; Ziangirova, G G; Iomdina, E N; Aliev, T I

    2005-01-01

    The paper presents the results of experimental use of a polyglycolide material-based filling for temporary episcleral filling in retinal detachment. Thorough comparative morphological and biomechanical studies of 120 experimental eyes in different periods after scleroplasty, by using an inflatable balloon catheter, homoscleral and polyglycolide fillings, have indicated that the polyglycolide filling material is completely lysed by ocular tissues within 60-90 days, which rules out a repeated surgical intervention for removal of temporary filling (for example, an inflatable balloon catheter), by preserving the constancy of the depth of scleral pressing-in. The short existence of a chemically indifferent polyglycolide filling in the ocular tissues excludes its negative effect on the surrounding structures of the eye, minimizes the likelihood of the occurrence of early postoperative complications, but thereby leading to a substantial increase in the biochemical stability of the scleral-and-chorioretinal complex in the early postoperative periods and ensuring increased resistance to dynamic loads, by forming a stable scleral-and-chorioretinal adhesion 3 months after surgery. The findings suggest that the designed polyglycolide explant has advantages and that it is expedient to introduce the new Russian resolving polyglycolide fiber explants into clinical practice (for scleroplastic operations).

  12. [Evaluation of experimental data obtained using new-generation CO2 laser in surgery].

    PubMed

    Morrone, G; Guzzardella, G A; Fini, M; Martini, L; Bacchini, P; Bertoni, F; Giardino, R

    1994-01-01

    In order to study the interaction between the laser and biological tissues, we realized an experimental "in vivo" model using 12 Wistar male adult rats (mean b.w. 300 gr.). On the animals, during general anesthesia and after an accurate shearing of the back, we performed a cutaneous lozenge in order to value the characteristics and the possibilities of a last generation laser. It concerns of a CO2 laser (EASY LASER SP5, CLASS IV F.D.A.) with the possibility of employing of different variables. During this study were evaluated the most interesting variables: frequency, power and duty cycle. Among the variables we identified the frequency of the application range of the superpulse effect and the selective photothermolysis. The histological and morphological studies performed on the cutaneous specimens after laser treatment, showed that the correct application of this kind of laser can be an effective help for the surgeon during clinical practice.

  13. An experimental study on laser-induced suturing of venous grafts in cerebral revascularization surgery

    NASA Astrophysics Data System (ADS)

    Puca, Alfredo; Albanese, Alessio; Esposito, Giuseppe; Maira, Giulio; Rossi, Giacomo; Pini, Roberto

    2005-04-01

    To test laser-assisted high flow bypass in cerebral revascularization procedures, we set up an experimental model on rabbits which included harvesting a jugular vein graft and its implantation on the common carotid artery through a double end-to-side anastomosis. The study was carried out on 25 New Zealand rabbits by performing on each animal the proximal anastomosis using conventional suturing, while the distal one was obtained by means of low-power diode laser welding in association with the topical application of Indocyanine Green (ICG) solution to enhance local absorption of the laser light. After the procedure, the animals were subjected to a follow-up from 2 to 9 days. Bypass patency was evaluated by means of Doppler study. The vascular segments were excised and evaluated by histological and immunohistochemical examinations. Utilization of the diode laser was associated with a substantial shortening of the operative time, as well as with a more active endothelial regeneration process at the anastomotic site.

  14. [Absorbable osteosynthesis: experimental and clinical approach in surgery of the hand].

    PubMed

    Merle, M; Voche, P H

    1994-01-01

    Given the advances in the field of high molecular-weight polylactides, it is now possible to obtain biomaterials of great strength with a resorption rate that ranges from a few months to several years. Experimental evaluation of the biomaterials was done in rabbits with implantation of intramedullary rods after fracture of the knee. The results of histological studies and assessment, using MR imaging, indicated good compatibility of the intramedullary rods. Applications for human clinical practice centered on metacarpophalangeal arthrodesis of the thumb performed for rheumatoid polyarthritis and intractable sprains of the metacarpophalangeal. Operations were performed on 52 patients with a rate of consolidation of 96%. No synovitis-like reactions were observed concurrent with massive release of the biomaterial. As a first step, this type of osteosynthesis could be applied to the upper extremity where stresses are relatively minimal. Eventually, screws of reduced diameter could be developed for the treatment of articular and unstable fractures of the metacarpophalangeals. There are already 3.5 mm-screws that can be used for malleolar fixation at the level of the lower extremity. Because of the wide variety of biomaterials that are currently available, it is important to be familiar with their composition, so that patients will be spared certain complications linked to resorption, especially inflammatory reactions. The biomaterials presented here belong to a class of biomaterials that have demonstrated good compatibility. At the present time, the cost of biodegradable materials remains high but it is important to emphasize the social and economic consequences of their use, since there is no need for a secondary procedure to remove them.

  15. Spherical mechanism analysis of a surgical robot for minimally invasive surgery -- analytical and experimental approaches.

    PubMed

    Rosen, Jacob; Lum, Mitch; Trimble, Denny; Hannaford, Blake; Sinanan, Mika

    2005-01-01

    Recent advances in technology have led to the fusion of MIS techniques and robot devices. However, current systems are large and cumbersome. Optimizing the surgical robot mechanism will eventually lead to its integration into the operating room (OR) of the future becoming the extended presence of the surgeon and nurses in a room occupied by the patient alone. By optimizing a spherical mechanism using data collected in-vivo during MIS procedures, this study is focused on a bottom-up approach to developing a new class of surgical robotic arms while maximizing their performance and minimizing their size. The spherical mechanism is a rotational manipulator with all axes intersecting at the center of the sphere. Locating the rotation center of the mechanism at the MIS port makes this class of mechanism a suitable candidate for the first two links of a surgical robot for MIS. The required dexterous workspace (DWS) is defined as the region in which 95% of the tool motions are contained based on in-vivo measurements. The extended dexterous workspace (EDWS) is defined as the entire abdominal cavity reachable by a MIS instruments. The DWS is defined by a right circular cone with a vertex angle of 60 degrees and the EDWS is defined by a cone with an elliptical cross section created by two orthogonal vertex angles of 60 degrees and 90 degrees. A compound function based on the mechanism's isotropy and the mechanism stiffness was considered as the performance metric cost function. Optimization across both the DWS and the EDWS lead to a serial mechanism configuration with link length angles of 74 degrees and 60 degrees for a serial configuration. This mechanism configuration maximized the kinematic performance in the DWS while keeping the EDWS as its reachable workspace. Surgeons, using a mockup of two mechanisms in a MIS setup, validated these results experimentally. From these experiments the serial configuration was deemed most applicable for MIS robotic applications compared

  16. The effect of a forced-air warming blanket on patients' end-tidal and transcutaneous carbon dioxide partial pressures during eye surgery under local anaesthesia: a single-blind, randomised controlled trial.

    PubMed

    Sukcharanjit, S; Tan, A S B; Loo, A V P; Chan, X L; Wang, C Y

    2015-12-01

    Surgical drapes used during eye surgery are impermeable to air and hence risk trapping air underneath them. We investigated the effect of a forced-air warming blanket on carbon dioxide accumulation under the drapes in patients undergoing eye surgery under local anaesthesia without sedation. Forty patients of ASA physical status 1 and 2 were randomly assigned to either the forced-air warmer (n = 20) or a control heated overblanket (n = 20). All patients were given 1 l.min(-1) oxygen. We measured transcutaneous and end-tidal carbon dioxide partial pressures, heart rate, arterial pressure, respiratory rate, temperature and oxygen saturation before and after draping, then every 5 min thereafter for 30 min. The mean (SD) transcutaneous carbon dioxide partial pressure in the forced-air warming group stayed constant after draping at 5.7 (0.2) kPa but rose to a maximum of 6.4 (0.4) kPa in the heated overblanket group (p = 0.0001 for the difference at time points 15 min and later). We conclude that forced-air warming reduces carbon dioxide accumulation under the drapes in patients undergoing eye surgery under local anaesthesia.

  17. Experimental and geochemical evidence for derivation of the El Capitan Granite, California, by partial melting of hydrous gabbroic lower crust

    USGS Publications Warehouse

    Ratajeski, K.; Sisson, T.W.; Glazner, A.F.

    2005-01-01

    Partial melting of mafic intrusions recently emplaced into the lower crust can produce voluminous silicic magmas with isotopic ratios similar to their mafic sources. Low-temperature (825 and 850??C) partial melts synthesized at 700 MPa in biotite-hornblende gabbros from the central Sierra Nevada batholith (Sisson et al. in Contrib Mineral Petrol 148:635-661, 2005) have major-element and modeled trace-element (REE, Rb, Ba, Sr, Th, U) compositions matching those of the Cretaceous El Capitan Granite, a prominent granite and silicic granodiorite pluton in the central part of the Sierra Nevada batholith (Yosemite, CA, USA) locally mingled with coeval, isotopically similar quartz diorite through gabbro intrusions (Ratajeski et al. in Geol Soc Am Bull 113:1486-1502, 2001). These results are evidence that the El Capitan Granite, and perhaps similar intrusions in the Sierra Nevada batholith with lithospheric-mantle-like isotopic values, were extracted from LILE-enriched, hydrous (hornblende-bearing) gabbroic rocks in the Sierran lower crust. Granitic partial melts derived by this process may also be silicic end members for mixing events leading to large-volume intermediate composition Sierran plutons such as the Cretaceous Lamarck Granodiorite. Voluminous gabbroic residues of partial melting may be lost to the mantle by their conversion to garnet-pyroxene assemblages during batholithic magmatic crustal thickening. ?? Springer-Verlag 2005.

  18. Biological and mechanical properties of an experimental glass-ionomer cement modified by partial replacement of CaO with MgO or ZnO.

    PubMed

    Kim, Dong-Ae; Abo-Mosallam, Hany; Lee, Hye-Young; Lee, Jung-Hwan; Kim, Hae-Won; Lee, Hae-Hyoung

    2015-01-01

    Some weaknesses of conventional glass ionomer cement (GIC) as dental materials, for instance the lack of bioactive potential and poor mechanical properties, remain unsolved.Objective The purpose of this study was to investigate the effects of the partial replacement of CaO with MgO or ZnO on the mechanical and biological properties of the experimental glass ionomer cements.Material and Methods Calcium fluoro-alumino-silicate glass was prepared for an experimental glass ionomer cement by melt quenching technique. The glass composition was modified by partial replacement (10 mol%) of CaO with MgO or ZnO. Net setting time, compressive and flexural properties, and in vitrorat dental pulp stem cells (rDPSCs) viability were examined for the prepared GICs and compared to a commercial GIC.Results The experimental GICs set more slowly than the commercial product, but their extended setting times are still within the maximum limit (8 min) specified in ISO 9917-1. Compressive strength of the experimental GIC was not increased by the partial substitution of CaO with either MgO or ZnO, but was comparable to the commercial control. For flexural properties, although there was no significance between the base and the modified glass, all prepared GICs marked a statistically higher flexural strength (p<0.05) and comparable modulus to control. The modified cements showed increased cell viability for rDPSCs.Conclusions The experimental GICs modified with MgO or ZnO can be considered bioactive dental materials.

  19. Biological and mechanical properties of an experimental glass-ionomer cement modified by partial replacement of CaO with MgO or ZnO

    PubMed Central

    Dong-Ae, KIM; Hany, ABO-MOSALLAM; Hye-Young, LEE; Jung-Hwan, LEE; Hae-Won, KIM; Hae-Hyoung, LEE

    2015-01-01

    Some weaknesses of conventional glass ionomer cement (GIC) as dental materials, for instance the lack of bioactive potential and poor mechanical properties, remain unsolved. Objective The purpose of this study was to investigate the effects of the partial replacement of CaO with MgO or ZnO on the mechanical and biological properties of the experimental glass ionomer cements. Material and Methods Calcium fluoro-alumino-silicate glass was prepared for an experimental glass ionomer cement by melt quenching technique. The glass composition was modified by partial replacement (10 mol%) of CaO with MgO or ZnO. Net setting time, compressive and flexural properties, and in vitro rat dental pulp stem cells (rDPSCs) viability were examined for the prepared GICs and compared to a commercial GIC. Results The experimental GICs set more slowly than the commercial product, but their extended setting times are still within the maximum limit (8 min) specified in ISO 9917-1. Compressive strength of the experimental GIC was not increased by the partial substitution of CaO with either MgO or ZnO, but was comparable to the commercial control. For flexural properties, although there was no significance between the base and the modified glass, all prepared GICs marked a statistically higher flexural strength (p<0.05) and comparable modulus to control. The modified cements showed increased cell viability for rDPSCs. Conclusions The experimental GICs modified with MgO or ZnO can be considered bioactive dental materials. PMID:26398508

  20. Experimental study on heat transfer enhancement of laminar ferrofluid flow in horizontal tube partially filled porous media under fixed parallel magnet bars

    NASA Astrophysics Data System (ADS)

    Sheikhnejad, Yahya; Hosseini, Reza; Saffar Avval, Majid

    2017-02-01

    In this study, steady state laminar ferroconvection through circular horizontal tube partially filled with porous media under constant heat flux is experimentally investigated. Transverse magnetic fields were applied on ferrofluid flow by two fixed parallel magnet bar positioned on a certain distance from beginning of the test section. The results show promising notable enhancement in heat transfer as a consequence of partially filled porous media and magnetic field, up to 2.2 and 1.4 fold enhancement were observed in heat transfer coefficient respectively. It was found that presence of both porous media and magnetic field simultaneously can highly improve heat transfer up to 2.4 fold. Porous media of course plays a major role in this configuration. Virtually, application of Magnetic field and porous media also insert higher pressure loss along the pipe which again porous media contribution is higher that magnetic field.

  1. Noncontrast and contrast enhanced MR imaging in the evaluation of partial ureteral obstruction: An experimental study in the micropig

    SciTech Connect

    Thurnher, S.; Tzika, A.A.; Hricak, H.; Mattei, P.; Aboseif, S.; Engelstad, B.; Price, D.C. )

    1989-07-01

    Twelve Yucatan micropigs (3 controls; 3 sham-operated; 6 with unilateral obstruction) were studied to assess the value of noncontrast and contrast-enhanced (Gadolinium-DTPA) magnetic resonance (MR) imaging in the evaluation of partial ureteral obstruction. MR findings were correlated with findings of quantitative (Tc-99m-DMSA) scintigraphy, and histology. On noncontrast T1-weighted images, the normal porcine kidney demonstrated good corticomedullary contrast (CMC = 16.8% +/- 5.0). Five minutes after administration of Gd-DTPA, there was enhancement of the renal cortex (+24.4%) and medulla (+46.2%), and CMC was no longer discernible. Enhancement of the urine within the collecting system (+119.1%) was also observed. The obstructed kidneys demonstrated marked thinning of the renal parenchyma and decreased signal intensity on noncontrast T1- and T2-weighted images (P less than 0.01). Urine in the dilated collecting system did not differ significantly from urine in controls except in the three animals with urinary tract infection (P less than 0.05). Five minutes following injection of Gd-DTPA, there was enhancement of the renal parenchyma in all kidneys. Excretion was seen in three pigs and no excretion in two. Thus, useful information can be obtained in partial ureteral obstruction from both pre-contrast and Gd-DTPA-enhanced MR images of the kidney.

  2. Optimising renal cancer patients for nephron-sparing surgery: a review of pre-operative considerations and peri-operative techniques for partial nephrectomy.

    PubMed

    Ertemi, Hani; Khetrapal, Pramit; Pavithran, Nevil M; Mumtaz, Faiz

    2017-02-03

    Nonmodifiable factors including pre-operative renal function and amount of healthy renal tissue preserved are the most important predictive factors that determine renal function after partial nephrectomy. Ischaemia time is an important modifiable risk factor and cold ischaemia time should be used if longer ischaemia time is anticipated. New techniques may have a role in maximising postoperative kidney function, but more robust studies are required to understand their potential benefits and risks.

  3. Experimental verification of the Kruskal-Shafranov stability limit in line-tied partial-toroidal plasmas

    SciTech Connect

    Oz, E.; Myers, C. E.; Yamada, M.; Ji, H.; Kulsrud, R. M.; Xie, J.

    2011-10-15

    The stability properties of partial-toroidal flux ropes are studied in detail in the laboratory, motivated by ubiquitous arched magnetic structures found on the solar surface. The flux ropes studied here are magnetized arc discharges formed between two electrodes in the Magnetic Reconnection Experiment (MRX) [Yamada et al., Phys. Plasmas 4, 1936 (1997)]. The three dimensional evolution of these flux ropes is monitored by a fast visible light framing camera, while their magnetic structure is measured by a variety of internal magnetic probes. The flux ropes are consistently observed to undergo large-scale oscillations as a result of an external kink instability. Using detailed scans of the plasma current, the guide field strength, and the length of the flux rope, we show that the threshold for kink stability is governed by the Kruskal-Shafranov limit for a flux rope that is held fixed at both ends (i.e., q{sub a} = 1).

  4. Cosmetic Surgery

    MedlinePlus

    ... Body Looking and feeling your best Cosmetic surgery Cosmetic surgery Teens might have cosmetic surgery for a ... about my body? What are the risks of cosmetic surgery? top People who have cosmetic surgery face ...

  5. Robot-assisted partial nephrectomy: Superiority over laparoscopic partial nephrectomy.

    PubMed

    Shiroki, Ryoichi; Fukami, Naohiko; Fukaya, Kosuke; Kusaka, Mamoru; Natsume, Takahiro; Ichihara, Takashi; Toyama, Hiroshi

    2016-02-01

    Nephron-sparing surgery has been proven to positively impact the postoperative quality of life for the treatment of small renal tumors, possibly leading to functional improvements. Laparoscopic partial nephrectomy is still one of the most demanding procedures in urological surgery. Laparoscopic partial nephrectomy sometimes results in extended warm ischemic time and severe complications, such as open conversion, postoperative hemorrhage and urine leakage. Robot-assisted partial nephrectomy exploits the advantages offered by the da Vinci Surgical System to laparoscopic partial nephrectomy, equipped with 3-D vision and a better degree in the freedom of surgical instruments. The introduction of the da Vinci Surgical System made nephron-sparing surgery, specifically robot-assisted partial nephrectomy, safe with promising results, leading to the shortening of warm ischemic time and a reduction in perioperative complications. Even for complex and challenging tumors, robotic assistance is expected to provide the benefit of minimally-invasive surgery with safe and satisfactory renal function. Warm ischemic time is the modifiable factor during robot-assisted partial nephrectomy to affect postoperative kidney function. We analyzed the predictive factors for extended warm ischemic time from our robot-assisted partial nephrectomy series. The surface area of the tumor attached to the kidney parenchyma was shown to significantly affect the extended warm ischemic time during robot-assisted partial nephrectomy. In cases with tumor-attached surface area more than 15 cm(2) , we should consider switching robot-assisted partial nephrectomy to open partial nephrectomy under cold ischemia if it is imperative. In Japan, a nationwide prospective study has been carried out to show the superiority of robot-assisted partial nephrectomy to laparoscopic partial nephrectomy in improving warm ischemic time and complications. By facilitating robotic technology, robot-assisted partial nephrectomy

  6. Experimental investigation of the electrical behavior of olivine during partial melting under pressure and application to the lunar mantle

    NASA Astrophysics Data System (ADS)

    Pommier, A.; Leinenweber, K.; Tasaka, M.

    2015-09-01

    Electrical conductivity measurements were performed during melting experiments of olivine compacts (dry and hydrous Fo77 and Fo90) at 4 and 6 GPa in order to investigate melt transport properties and quantify the effect of partial melting on electrical properties. Experiments were performed in the multi-anvil apparatus and electrical measurements were conducted using the impedance spectroscopy technique with the two-electrode method. Changes in impedance spectra were used to identify the transition from an electrical response controlled by the solid matrix to an electrical response controlled by the melt phase. This transition occurs slightly above the solidus temperature and lasts until Tsolidus + 75 °C (±25). At higher temperature, a significant increase in conductivity (corresponding to an increase in conductivity values by a factor ranging from ∼30 to 100) is observed, consistent with the transition from a tube-dominated network to a structure in which melt films and pools become prominent features. This increase in conductivity corresponds to an abrupt jump for all dry samples and to a smoother increase for the hydrous sample. It is followed by a plateau at higher temperature, suggesting that the electrical response of the investigated samples lacks sensitivity to temperature at an advanced stage of partial melting. Electron microprobe analyses on quenched products indicated an increase in Mg# (molar Mg / (Mg +Fe)) of olivine during experiments (∼77-93 in the quenched samples with an initial Fo77 composition and ∼92-97 in the quenched samples with an initial Fo90 composition) due to the partitioning of iron to the melt phase. Assuming a respective melt fraction of 0.10 and 0.20 before and after the phase of significant increase in conductivity, in agreement with previous electrical and permeability studies, our results can be reproduced satisfactorily by two-phase electrical models (the Hashin and Shtrikman bounds and the modified brick layer model

  7. Size-dependent selectivity and activity of silver nanoclusters in the partial oxidation of propylene to propylene oxide and acrolein : A joint experimental and theoretical study.

    SciTech Connect

    Molina, L M.; Lee, S.; Sell, K.; Barcaro, G.; Fortunelli, A.; Lee, B.; Seifert, S.; Winans, R. E.; Elam, J. W.; Pellin, M. J.; Barke, I.; von Oeynhausen, V.; Lei, Y.; Meyer, R. J.; Alonso, J. A.; Fraile-Rodriguez, A.; Kleibert, A.; Giorgio, S.; Henry, C. R.; Heinz Meiwes-Broer, K.; Vadja, S.; Univ. de Valladolid; Univ. Rostock; IPCF-CNR; Univ. of Illinois at Chicago; Swiss Light Source; CINaM-CNRS and Aix-Marseille Univ.; Yale Univ.

    2011-02-02

    Model silver nanocatalysts between 9 and 23 nm in size were prepared by size-selected cluster deposition from a free cluster beam on amorphous alumina films and their size-dependent catalytic performance studied in the partial oxidation of propylene under realistic reaction conditions. Smaller clusters preferentially produced acrolein, while the 23 nm particles were considerably more selective towards the formation of propylene oxide, at reaction rates far exceeding those previously reported for larger silver particles. The activity of clusters dropped significantly with increasing particle size. First-principle calculations, of the activation energies for oxygen adsorption and its dissociation, at variable surface coverage yielded surface energies which resulted in particle shapes resembling the experimentally observed shapes of partially oxidized silver clusters. The calculated activation barriers for propylene oxide and acrolein formation on various facets and on the edges of the nanoparticles provided detailed information about the energetics of the competing reaction pathways. The size- and corresponding morphology dependent theoretical activity and selectivity are in good accord with experimental observations.

  8. Experimental approach to the anion problem in DFT calculation of the partial charge transfer during adsorption at electrochemical interfaces

    NASA Astrophysics Data System (ADS)

    Marichev, V. A.

    2005-08-01

    In DFT calculation of the charge transfer (Δ N), anions pose a special problem since their electron affinities are unknown. There is no method for calculating reasonable values of the absolute electronegativity ( χA) and chemical hardness ( ηA) for ions from data of species themselves. We propose a new approach to the experimental measurement of χA at the condition: Δ N = 0 at which η values may be neglected and χA = χMe. Electrochemical parameters corresponding to this condition may be obtained by the contact electric resistance method during in situ investigation of anion adsorption in the particular system anion-metal.

  9. Experimental study of vorticity-strain rate interaction in turbulent partially-premixed jet flames using tomographic particle image velocimetry

    DOE PAGES

    Coriton, Bruno; Frank, Jonathan H.

    2016-02-16

    In turbulent flows, the interaction between vorticity, ω, and strain rate, s, is considered a primary mechanism for the transfer of energy from large to small scales through vortex stretching. The ω-s coupling in turbulent jet flames is investigated using tomographic particle image velocimetry (TPIV). TPIV provides a direct measurement of the three-dimensional velocity field from which ω and s are determined. The effects of combustion and mean shear on the ω-s interaction are investigated in turbulent partially premixed methane/air jet flames with high and low probabilities of localized extinction as well as in a non-reacting isothermal air jet withmore » Reynolds number of approximately 13,000. Results show that combustion causes structures of high vorticity and strain rate to agglomerate in highly correlated, elongated layers that span the height of the probe volume. In the non-reacting jet, these structures have a more varied morphology, greater fragmentation, and are not as well correlated. The enhanced spatiotemporal correlation of vorticity and strain rate in the stable flame results in stronger ω-s interaction characterized by increased enstrophy and strain-rate production rates via vortex stretching and straining, respectively. The probability of preferential local alignment between ω and the eigenvector of the intermediate principal strain rate, s2, which is intrinsic to the ω-s coupling in turbulent flows, is larger in the flames and increases with the flame stability. The larger mean shear in the flame imposes a preferential orientation of ω and s2 tangential to the shear layer. The extensive and compressive principal strain rates, s1 and s3, respectively, are preferentially oriented at approximately 45° with respect to the jet axis. As a result, the production rates of strain and vorticity tend to be dominated by instances in which ω is parallel to the s1¯-s2¯ plane and orthogonal to s3¯.« less

  10. Experimental study of vorticity-strain rate interaction in turbulent partially-premixed jet flames using tomographic particle image velocimetry

    SciTech Connect

    Coriton, Bruno; Frank, Jonathan H.

    2016-02-16

    In turbulent flows, the interaction between vorticity, ω, and strain rate, s, is considered a primary mechanism for the transfer of energy from large to small scales through vortex stretching. The ω-s coupling in turbulent jet flames is investigated using tomographic particle image velocimetry (TPIV). TPIV provides a direct measurement of the three-dimensional velocity field from which ω and s are determined. The effects of combustion and mean shear on the ω-s interaction are investigated in turbulent partially premixed methane/air jet flames with high and low probabilities of localized extinction as well as in a non-reacting isothermal air jet with Reynolds number of approximately 13,000. Results show that combustion causes structures of high vorticity and strain rate to agglomerate in highly correlated, elongated layers that span the height of the probe volume. In the non-reacting jet, these structures have a more varied morphology, greater fragmentation, and are not as well correlated. The enhanced spatiotemporal correlation of vorticity and strain rate in the stable flame results in stronger ω-s interaction characterized by increased enstrophy and strain-rate production rates via vortex stretching and straining, respectively. The probability of preferential local alignment between ω and the eigenvector of the intermediate principal strain rate, s2, which is intrinsic to the ω-s coupling in turbulent flows, is larger in the flames and increases with the flame stability. The larger mean shear in the flame imposes a preferential orientation of ω and s2 tangential to the shear layer. The extensive and compressive principal strain rates, s1 and s3, respectively, are preferentially oriented at approximately 45° with respect to the jet axis. As a result, the production rates of strain and vorticity tend to be dominated by instances in which ω is parallel to the s1¯-s2¯ plane and orthogonal

  11. Accelerated Partial Breast Irradiation: 5-Year Results of the German-Austrian Multicenter Phase II Trial Using Interstitial Multicatheter Brachytherapy Alone After Breast-Conserving Surgery

    SciTech Connect

    Strnad, Vratislav; Hildebrandt, Guido; Poetter, Richard; Hammer, Josef; Hindemith, Marion; Resch, Alexandra; Spiegl, Kurt; Lotter, Michael; Uter, Wolfgang; Bani, Mayada; Kortmann, Rolf-Dieter; Beckmann, Matthias W.; Fietkau, Rainer; Ott, Oliver J.

    2011-05-01

    Purpose: To evaluate the impact of accelerated partial breast irradiation on local control, side effects, and cosmesis using multicatheter interstitial brachytherapy as the sole method for the adjuvant local treatment of patients with low-risk breast cancer. Methods and Materials: 274 patients with low-risk breast cancer were treated on protocol. Patients were eligible for the study if the tumor size was < 3 cm, resection margins were clear by at least 2 mm, no lymph node metastases existed, age was >35 years, hormone receptors were positive, and histologic grades were 1 or 2. Of the 274 patients, 175 (64%) received pulse-dose-rate brachytherapy (D{sub ref} = 50 Gy). and 99 (36%) received high-dose-rate brachytherapy (D{sub ref} = 32.0 Gy). Results: Median follow-up was 63 months (range, 9-103). Only 8 of 274 (2.9%) patients developed an ipsilateral in-breast tumor recurrence at the time of analysis. The 5-year actuarial local recurrence-free survival probability was 98%. The 5- year overall and disease-free survival probabilities of all patients were 97% and 96%, respectively. Contralateral in-breast malignancies were detected in 2 of 274 (0.7%) patients, and distant metastases occurred in 6 of 274 (2.2%). Late side effects {>=}Grade 3 (i.e., breast tissue fibrosis and telangiectasia) occurred in 1 patient (0.4%, 95%CI:0.0-2.0%) and 6 patients (2.2%, 95%CI:0.8-4.7%), respectively. Cosmetic results were good to excellent in 245 of 274 patients (90%). Conclusions: The long-term results of this prospective Phase II trial confirm that the efficacy of accelerated partial breast irradiation using multicatheter brachytherapy is comparable with that of whole breast irradiation and that late side effects are negligible.

  12. Modelling of experimentally created partial-thickness human skin burns and subsequent therapeutic cooling: a new measure for cooling effectiveness.

    PubMed

    Van de Sompel, Dominique; Kong, Tze Yean; Ventikos, Yiannis

    2009-07-01

    Rapid post-injury cooling of a skin burn has been shown to have both symptomatic and therapeutic benefits. However, the latter cannot be explained by temperature reduction alone, and must thus be secondary to an altered biological response. In this study, we construct a computational model to calculate the heat transfer and damage accumulation in human skin during and after a burn. This enables us to assess the effectiveness of various cooling protocols (involving both free and forced convection to air and water respectively) in terms of their reduction in Arrhenius tissue damage. In this process, we propose an extension of the Arrhenius damage model in the form of a new measure xi, which estimates the relevance of post-burn accrued damage. It was found that the reduction in Arrhenius damage integrals near the skin surface was too small to be physiologically relevant. Hence our results confirm that while the reduction in tissue temperatures is indeed quicker, the therapeutic benefit of cooling cannot be explained by thermal arguments (i.e. based on Arrhenius damage models) alone. We plan to validate this hypothesis by conducting future microarray analyses of differential gene expression in cooled and non-cooled burn lesions. Our computational model will support such experiments by calculating the necessary conditions to produce a burn of specified severity for a given experimental setup.

  13. Purple Pitcher Plant (Sarracenia rosea) Dieback and Partial Community Disassembly following Experimental Storm Surge in a Coastal Pitcher Plant Bog

    PubMed Central

    Abbott, Matthew J.; Battaglia, Loretta L.

    2015-01-01

    Sea-level rise and frequent intense hurricanes associated with climate change will result in recurrent flooding of inland systems such as Gulf Coastal pitcher plant bogs by storm surges. These surges can transport salt water and sediment to freshwater bogs, greatly affecting their biological integrity. Purple pitcher plants (Sarracenia rosea) are Gulf Coast pitcher plant bog inhabitants that could be at a disadvantage under this scenario because their pitcher morphology may leave them prone to collection of saline water and sediment after a surge. We investigated the effects of storm surge water salinity and sediment type on S. rosea vitality, plant community structure, and bog soil-water conductivity. Plots (containing ≥1 ramet of S. rosea) were experimentally flooded with fresh or saline water crossed with one of three sediment types (local, foreign, or no sediment). There were no treatment effects on soil-water conductivity; nevertheless, direct exposure to saline water resulted in significantly lower S. rosea cover until the following season when a prescribed fire and regional drought contributed to the decline of all the S. rosea to near zero percent cover. There were also significant differences in plant community structure between treatments over time, reflecting how numerous species increased in abundance and a few species decreased in abundance. However, in contrast to S. rosea, most of the other species in the community appeared resilient to the effects of storm surge. Thus, although the community may be somewhat affected by storm surge, those few species that are particularly sensitive to the storm surge disturbance will likely drop out of the community and be replaced by more resilient species. Depending on the longevity of these biological legacies, Gulf Coastal pitcher plant bogs may be incapable of fully recovering if they become exposed to storm surge more frequently due to climate change. PMID:25874369

  14. Purple pitcher plant (Sarracenia rosea) Dieback and partial community disassembly following experimental storm surge in a coastal pitcher plant bog.

    PubMed

    Abbott, Matthew J; Battaglia, Loretta L

    2015-01-01

    Sea-level rise and frequent intense hurricanes associated with climate change will result in recurrent flooding of inland systems such as Gulf Coastal pitcher plant bogs by storm surges. These surges can transport salt water and sediment to freshwater bogs, greatly affecting their biological integrity. Purple pitcher plants (Sarracenia rosea) are Gulf Coast pitcher plant bog inhabitants that could be at a disadvantage under this scenario because their pitcher morphology may leave them prone to collection of saline water and sediment after a surge. We investigated the effects of storm surge water salinity and sediment type on S. rosea vitality, plant community structure, and bog soil-water conductivity. Plots (containing ≥1 ramet of S. rosea) were experimentally flooded with fresh or saline water crossed with one of three sediment types (local, foreign, or no sediment). There were no treatment effects on soil-water conductivity; nevertheless, direct exposure to saline water resulted in significantly lower S. rosea cover until the following season when a prescribed fire and regional drought contributed to the decline of all the S. rosea to near zero percent cover. There were also significant differences in plant community structure between treatments over time, reflecting how numerous species increased in abundance and a few species decreased in abundance. However, in contrast to S. rosea, most of the other species in the community appeared resilient to the effects of storm surge. Thus, although the community may be somewhat affected by storm surge, those few species that are particularly sensitive to the storm surge disturbance will likely drop out of the community and be replaced by more resilient species. Depending on the longevity of these biological legacies, Gulf Coastal pitcher plant bogs may be incapable of fully recovering if they become exposed to storm surge more frequently due to climate change.

  15. Plastic Surgery

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Plastic Surgery KidsHealth > For Teens > Plastic Surgery Print A ... her forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word " ...

  16. Outpatient Surgery

    MedlinePlus

    ... Outpatient Surgery Share this Page Preparing For Surgery Effects of Anesthesia Children and Anesthesia Pregnancy and Anesthesia Seniors and Anesthesia Surgery Risks Anesthesia Awareness Obesity and Anesthesia Sleep Apnea and Anesthesia Smoking and Anesthesia Outpatient Surgery ...

  17. Generation of Chimeric "ABS Nanohemostat" Complex and Comparing Its Histomorphological In Vivo Effects to the Traditional Ankaferd Hemostat in Controlled Experimental Partial Nephrectomy Model.

    PubMed

    Huri, Emre; Beyazit, Yavuz; Mammadov, Rashad; Toksoz, Sila; Tekinay, Ayse B; Guler, Mustafa O; Ustun, Huseyin; Kekilli, Murat; Dadali, Mumtaz; Celik, Tugrul; Astarci, Müzeyyen; Haznedaroglu, Ibrahim C

    2013-01-01

    Purpose. Using the classical Ankaferd Blood Stopper (ABS) solution to create active hemostasis during partial nephrectomy (PN) may not be so effective due to insufficient contact surface between the ABS hemostatic liquid agent and the bleeding area. In order to broaden the contact surface, we generated a chimeric hemostatic agent, ABS nanohemostat, via combining a self-assembling peptide amphiphile molecule with the traditional Ankaferd hemostat. Materials and Methods. In order to generate ABS nanohemostat, a positively charged Peptide Amphiphile (PA) molecule was synthesized by using solid phase peptide synthesis. For animal experiments, 24 Wistar rats were divided into the following 4 groups: Group 1: control; Group 2: conventional PN with only 0.5 ml Ankaferd hemostat; Group 3: conventional PN with ABS + peptide gel; Group 4: conventional PN with only 0.5 ml peptide solution. Results. Mean warm ischemia times (WITs) were 232.8  ±  56.3, 65.6 ± 11.4, 75.5 ± 17.2, and 58.1 ± 17.6 seconds in Group 1 to Group 4, respectively. Fibrosis was not different among the groups, while inflammation was detected to be significantly different in G3 and G4. Conclusions. ABS nanohemostat has comparable hemostatic efficacy to the traditional Ankaferd hemostat in the partial nephrectomy experimental model. Elucidation of the cellular and tissue effects of this chimeric compound may establish a catalytic spark and open new avenues for novel experimental and clinical studies in the battlefield of hemostasis.

  18. Partially anaortic clampless off-pump coronary artery bypass prevents neurologic injury compared to on-pump coronary surgery: a propensity score-matched study on 286 patients.

    PubMed

    Bassano, Carlo; Bovio, Emanuele; Uva, Floriano; Iacobelli, Simona; Iasevoli, Nicola; Farinaccio, Andrea; Ruvolo, Giovanni

    2016-09-01

    Anaortic coronary artery bypass proved to prevent early neurologic injury compared to on-pump CABG. The Cardica PAS-Port(®) is a fully automated device that might be able to perform proximal aorto-venous anastomoses without an increased embolic risk. We evaluated early post-operative neurologic outcome in a matched population following clampless OPCAB (CCAB: either "all-arterial" or with automatically anastomosed venous grafts) or on-pump CABG. 366 consecutive patients were submitted to isolated coronary bypass by a single surgeon experienced in both off and on-pump procedures between January 2009 and December 2013. Of these patients, 223 underwent a clampless off-pump revascularization. After propensity score matching, 143 pairs were selected, who received either off-pump or on-pump surgery. In the off-pump group, CCAB was performed with an all-arterial approach (n = 33) or with automated proximal anastomosis of the venous graft(s) by means of the Cardica PAS-Port(®) connector (n = 110). Neurologic injury was defined as non-reversible (NRNI: lethal coma or stroke) or reversible (RNI: TIA or delirium). Operative mortality was 2.4 % (CCAB 1.4 %; CABG 3.5 %; p = 0.14). The global rate of early neurologic injury was 5.6 % (CCAB 2.1 vs. CABG 9.1 %; p = 0.006). Incidence was 1.4 % for NRNI (CCAB 0 vs. CABG 2.8 %; p = 0.04) and 4.2 % for RNI (CCAB 2.1 vs. CABG 6.3 %; p = 0.06). No differences were found among other major perioperative outcomes. CCAB prevents both early post-operative RNI and NRNI. This result can be achieved with a totally anaortic strategy and also with the aid of a fully automated device for proximal aorto-venous anastomoses.

  19. Partial Least Squares with Structured Output for Modelling the Metabolomics Data Obtained from Complex Experimental Designs: A Study into the Y-Block Coding

    PubMed Central

    Xu, Yun; Muhamadali, Howbeer; Sayqal, Ali; Dixon, Neil; Goodacre, Royston

    2016-01-01

    Partial least squares (PLS) is one of the most commonly used supervised modelling approaches for analysing multivariate metabolomics data. PLS is typically employed as either a regression model (PLS-R) or a classification model (PLS-DA). However, in metabolomics studies it is common to investigate multiple, potentially interacting, factors simultaneously following a specific experimental design. Such data often cannot be considered as a “pure” regression or a classification problem. Nevertheless, these data have often still been treated as a regression or classification problem and this could lead to ambiguous results. In this study, we investigated the feasibility of designing a hybrid target matrix Y that better reflects the experimental design than simple regression or binary class membership coding commonly used in PLS modelling. The new design of Y coding was based on the same principle used by structural modelling in machine learning techniques. Two real metabolomics datasets were used as examples to illustrate how the new Y coding can improve the interpretability of the PLS model compared to classic regression/classification coding. PMID:27801817

  20. Effect of three different bariatric obesity surgery procedures on nutrient and energy digestibility using a swine experimental model

    PubMed Central

    Hodgkinson, Suzanne Marie; Riveros, José Luis; Bas, Fernando

    2015-01-01

    Morbid obesity is a worldwide health concern that compromises life quality and health status of obese human subjects. Bariatric surgery for treating morbid obesity remains as one of the best alternatives to promote excess weight loss and to reduce co-morbidities. We have not found studies reporting nutrients and energy balance considering digestibility trials in humans following surgery. The purpose of this study was to determine protein, lipid, fiber, energy, calcium, and phosphorous digestibility in a swine model that underwent ileal transposition (IT), sleeve gastrectomy with ileal transposition (SGIT), Roux-en-Y gastric bypass (RYGBP), and with sham operated animals (SHAM). Thirty-two pigs were randomly assigned to four laparoscopic procedures: IT (n = 8), RYGBP (n = 8), SGIT (n = 8), and Sham-operated pigs (n = 8). From day 0 postsurgery to 130, pigs were weighed monthly to determine live weight and weight gain was calculated for each month postsurgery until day 130. Food intake in a metabolic weight basis was calculated by measuring ad libitum food intake at day 130. Swine were fitted into metabolic crates to determine digestibility coefficients of dry matter, protein, fat, fiber, ash, energy, calcium, and phosphorous from day 130. A one-way ANOVA and Student–Newman–Keuls were used to detect differences in weight, food intake, and digestibility coefficients. Digestibility values for dry matter, fiber, phosphorus, and energy showed no differences among groups (P > 0.05). However, significant differences (P ≤ 0.05) were encountered among groups for fat, protein, ash, and calcium digestibilities. The RYGBP procedure, when applied to the pig model, significantly reduced calcium, fat, and ash digestibility, which did not occur with SGIT or IT procedure, when compared with Sham-operated animals. PMID:25711878

  1. Effect of three different bariatric obesity surgery procedures on nutrient and energy digestibility using a swine experimental model.

    PubMed

    Gandarillas, Mónica; Hodgkinson, Suzanne Marie; Riveros, José Luis; Bas, Fernando

    2015-09-01

    Morbid obesity is a worldwide health concern that compromises life quality and health status of obese human subjects. Bariatric surgery for treating morbid obesity remains as one of the best alternatives to promote excess weight loss and to reduce co-morbidities. We have not found studies reporting nutrients and energy balance considering digestibility trials in humans following surgery. The purpose of this study was to determine protein, lipid, fiber, energy, calcium, and phosphorous digestibility in a swine model that underwent ileal transposition (IT), sleeve gastrectomy with ileal transposition (SGIT), Roux-en-Y gastric bypass (RYGBP), and with sham operated animals (SHAM). Thirty-two pigs were randomly assigned to four laparoscopic procedures: IT (n = 8), RYGBP (n = 8), SGIT (n = 8), and Sham-operated pigs (n = 8). From day 0 postsurgery to 130, pigs were weighed monthly to determine live weight and weight gain was calculated for each month postsurgery until day 130. Food intake in a metabolic weight basis was calculated by measuring ad libitum food intake at day 130. Swine were fitted into metabolic crates to determine digestibility coefficients of dry matter, protein, fat, fiber, ash, energy, calcium, and phosphorous from day 130. A one-way ANOVA and Student-Newman-Keuls were used to detect differences in weight, food intake, and digestibility coefficients. Digestibility values for dry matter, fiber, phosphorus, and energy showed no differences among groups (P > 0.05). However, significant differences (P ≤ 0.05) were encountered among groups for fat, protein, ash, and calcium digestibilities. The RYGBP procedure, when applied to the pig model, significantly reduced calcium, fat, and ash digestibility, which did not occur with SGIT or IT procedure, when compared with Sham-operated animals.

  2. Minimally invasive valve surgery.

    PubMed

    Woo, Y Joseph; Seeburger, Joerg; Mohr, Friedrich W

    2007-01-01

    As alternatives to standard sternotomy, surgeons have developed innovative, minimally invasive approaches to conducting valve surgery. Through very small skin incisions and partial upper sternal division for aortic valve surgery and right minithoracotomy for mitral surgery, surgeons have become adept at performing complex valve procedures. Beyond cosmetic appeal, apparent benefits range from decreased pain and bleeding to improved respiratory function and recovery time. The large retrospective studies and few small prospective randomized studies are herein briefly summarized. The focus is then directed toward describing specific intraoperative technical details in current clinical use, covering anesthetic preparation, incision, mediastinal access, cardiovascular cannulation, valve exposure, and valve reconstruction. Finally, unique situations such as pulmonic valve surgery, reoperations, beating heart surgery, and robotics are discussed.

  3. Robotic surgery

    MedlinePlus

    Robot-assisted surgery; Robotic-assisted laparoscopic surgery; Laparoscopic surgery with robotic assistance ... computer station and directs the movements of a robot. Small surgical tools are attached to the robot's ...

  4. Apparent partial resetting of U-Th-Pb systems in experimentally altered monazite resulting from nano-mixtures due to incomplete replacement.

    NASA Astrophysics Data System (ADS)

    Grand'homme, Alexis; Janots, Emilie; Seydoux-Guillaume, Anne-Magali; Guillaume, Damien; Bosse, Valérie; Magnin, Valérie

    2016-04-01

    Hydrothermal alteration experiments of natural monazite crystals (Manangotry, Madagascar; 555 Ma) under alkali conditions (NaOH 1M in 18O doped solution) at low temperature conditions (300, 400, 500 and 600°C), 200 MPa, were conducted to clarify the origin of unsupported Pb (radiogenic or not) in altered monazite (Seydoux-Guillaume et al., 2012). At 300°C, no evidence of monazite replacement was observed. From 400 to 600°C, experimental products show a replacement texture with pristine monazite (Mnz1) surrounded by an alteration rim with a different composition (SEM and EPMA). In the altered domains, in-situ isotopic and chemical U-Th-Pb dating yields intermediate ages between original monazite (555 Ma) and complete experimental resetting (0 Ma). Incomplete resetting is due to the systematic presence of Pb in altered domains, whose concentration decreases with increasing temperature. Transmission Electron Microscope (TEM) observations reveal an incomplete replacement of Mnz1 by a secondary monazite (Mnz2), free of Pb, within the altered domain. The latter domain, apparently homogeneous in BSE images, is in fact constituted by closely associated nano-mixtures of Mnz1 and Mnz2. Furthermore, the volume of Mnz2 within the altered domain, i.e. the efficiency of replacement, increases with increasing temperature. Apparent partial resetting of U-Th-Pb systems results from the unavoidable nano-mixture of different proportion of Mnz1 and Mnz2 within the analytical microvolume (EPMA, LA-ICP-MS). This study therefore indicates that the micrometric resolution (even the 5 μm3 for EPMA) of in-situ dating techniques may be not sufficient to solve such nano-replacement domains, especially when alteration occurs at low-temperature. Ref: Seydoux-Guillaume, A.-M., Montel, J.-M., Bingen, B., Bosse, V., de Parseval, P., Paquette, J.-L., Janots, E., and Wirth, R., (2012). Chemical Geology, v. 330-331, p. 140-158.

  5. Vaccination with a novel recombinant Leishmania antigen plus MPL provides partial protection against L. donovani challenge in experimental model of visceral leishmaniasis.

    PubMed

    Bhardwaj, Suvercha; Vasishta, R K; Arora, Sunil K

    2009-01-01

    The acquisition of immunity following subclinical or resolved infection with the intracellular parasite Leishmania donovani suggests that vaccination could prevent visceral leishmaniasis. The characteristics and in vitro stimulating capability of the recombinant proteins expressed by previously identified clones on the basis of their capacity to stimulate an indigenously established Leishmania-specific cell line leading to high level of IFN-gamma suggested these to be potential candidates for immunoprophylaxis against leishmaniasis. In this study, we investigated the protective efficacy of purified recombinant proteins from two of the identified cDNA clones along with the adjuvant MPL, in a hamster model of experimental leishmaniasis. We demonstrate here that the immunization of animals with one of the recombinant proteins (rF14) having 97% similarity to C1 clone of L. chagasi ribosomal protein gene P0 (rLiP0) along with MPL provided partial protection against the virulent challenge of L. donovani. The absence of antigen-specific lymphoproliferative responses in these immunized animals may be responsible for the lack of complete and long-lasting protection.

  6. Experimental Cancer Cachexia Changes Neuron Numbers and Peptide Levels in the Intestine: Partial Protective Effects after Dietary Supplementation with L-Glutamine

    PubMed Central

    Vicentini, Geraldo E.; Fracaro, Luciane; de Souza, Sara R. G.; Martins, Heber A.; Guarnier, Flávia A.; Zanoni, Jacqueline N.

    2016-01-01

    Gastrointestinal dysmotility frequently occurs in cancer cachexia and may result from damage to enteric innervation caused by oxidative stress, especially due to glutathione depletion. We assessed the effect of dietary supplementation with 20 g/kg l-glutamine (a glutathione precursor) on the intrinsic innervation of the enteric nervous system in healthy and Walker 256 tumor-bearing Wistar rats during the development of experimental cachexia (14 days), in comparison with non-supplemented rats, by using immunohistochemical methods and Western blotting. The total neural population and cholinergic subpopulation densities in the myenteric plexus, as well as the total population and VIPergic subpopulation in the submucosal plexus of the jejunum and ileum, were reduced in cachectic rats, resulting in adaptive morphometric alterations and an increase in vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP) expression, suggesting a neuroplastic response. l-glutamine supplementation prevented decrease in myenteric neuronal density in the ileum, morphometric alterations in the neurons and nerve fibers (in both the plexuses of the jejunum and ileum), and the overexpression of VIP and CGRP. Cancer cachexia severely affected the intrinsic innervation of the jejunum and ileum to various degrees and this injury seems to be associated with adaptive neural plasticity. l-glutamine supplementation presented partial protective effects on the enteric innervation against cancer cachexia, possibly by attenuating oxidative stress. PMID:27635657

  7. Beneficial cross-protection of allergen-specific immunotherapy on airway eosinophilia using unrelated or a partial repertoire of allergen(s) implicated in experimental feline asthma.

    PubMed

    Reinero, Carol; Lee-Fowler, Tekla; Chang, Chee-Hoon; Cohn, Leah; Declue, Amy

    2012-06-01

    The study hypothesis was that in experimentally asthmatic cats rush immunotherapy (RIT) using allergens not completely matched with sensitizing allergen(s) would at least partially attenuate the asthmatic phenotype and modulate the aberrant immune response. In phase I, cats sensitized to Bermuda grass allergen (BGA), house dust mite allergen (HDMA) or placebo received BGA RIT. In phase II, cats dually sensitized to BGA and HDMA received RIT using BGA, HDMA or placebo. Efficacy of RIT was assessed using percentage bronchoalveolar lavage fluid (BALF) eosinophils. Additionally, a variety of immunologic assays were performed. Eosinophilic airway inflammation significantly decreased over time in asthmatic cats given RIT using sensitizing allergen or unrelated allergen (P<0.001). In dually sensitized cats, single allergen RIT but not placebo reduced airway eosinophilia (P=0.038). Differences in allergen-specific lymphocyte proliferation, in the number of IL-10 producing cells and in the percentage T regulatory cells were detected between asthmatic cats getting RIT and controls. Cross-protection manifested by reduced airway eosinophilia was noted in cats treated with RIT allergens which did not completely match allergen used in asthma induction. However, the mechanism of immunologic tolerance may differ when improperly matched allergens to the sensitizing allergens are used in RIT.

  8. Does Laser Surgery Interfere with Optical Nerve Identification in Maxillofacial Hard and Soft Tissue?--An Experimental Ex Vivo Study.

    PubMed

    Bergauer, Bastian; Knipfer, Christian; Amann, Andreas; Rohde, Maximilian; Tangermann-Gerk, Katja; Adler, Werner; Schmidt, Michael; Nkenke, Emeka; Stelzle, Florian

    2015-10-01

    The protection of sensitive structures (e.g., nerves) from iatrogenic damage is of major importance when performing laser surgical procedures. Especially in the head and neck area both function and esthetics can be affected to a great extent. Despite its many benefits, the surgical utilization of a laser is therefore still limited to superficial tissue ablation. A remote feedback system which guides the laser in a tissue-specific way would provide a remedy. In this context, it has been shown that nerval structures can be specifically recognized by their optical diffuse reflectance spectra both before and after laser ablation. However, for a translation of these findings to the actual laser ablation process, a nerve protection within the laser pulse is of utmost significance. Thus, it was the aim of the study to evaluate, if the process of Er:YAG laser surgery--which comes with spray water cooling, angulation of the probe (60°) and optical process emissions--interferes with optical tissue differentiation. For the first time, no stable conditions but the ongoing process of laser tissue ablation was examined. Therefore, six different tissue types (nerve, skin, muscle, fat, cortical and cancellous bone) were acquired from 15 pig heads. Measurements were performed during Er:YAG laser ablation. Diffuse reflectance spectra (4500, wavelength range: 350-650 nm) where acquired. Principal component analysis (PCA) and quadratic discriminant analysis (QDA) were calculated for classification purposes. The clinical highly relevant differentiation between nerve and bone was performed correctly with an AUC of 95.3% (cortial bone) respectively 92.4% (cancellous bone). The identification of nerve tissue against the biological very similar fat tissue yielded good results with an AUC value of 83.4% (sensitivity: 72.3%, specificity: of 82.3%). This clearly demonstrates that nerve identification by diffuse reflectance spectroscopy works reliably in the ongoing process of laser ablation

  9. Weight Loss Surgery (Bariatric Surgery) (For Parents)

    MedlinePlus

    ... 1- to 2-Year-Old Weight Loss Surgery (Bariatric Surgery) KidsHealth > For Parents > Weight Loss Surgery (Bariatric Surgery) ... or bariatric surgery might be an option. About Bariatric Surgery Bariatric surgery had its beginnings in the 1960s, ...

  10. On the Experimental and Theoretical Investigations of Lean Partially Premixed Combustion, Burning Speed, Flame Instability and Plasma Formation of Alternative Fuels at High Temperatures and Pressures

    NASA Astrophysics Data System (ADS)

    Askari, Omid

    This dissertation investigates the combustion and injection fundamental characteristics of different alternative fuels both experimentally and theoretically. The subjects such as lean partially premixed combustion of methane/hydrogen/air/diluent, methane high pressure direct-injection, thermal plasma formation, thermodynamic properties of hydrocarbon/air mixtures at high temperatures, laminar flames and flame morphology of synthetic gas (syngas) and Gas-to-Liquid (GTL) fuels were extensively studied in this work. These subjects will be summarized in three following paragraphs. The fundamentals of spray and partially premixed combustion characteristics of directly injected methane in a constant volume combustion chamber have been experimentally studied. The injected fuel jet generates turbulence in the vessel and forms a turbulent heterogeneous fuel-air mixture in the vessel, similar to that in a Compressed Natural Gas (CNG) Direct-Injection (DI) engines. The effect of different characteristics parameters such as spark delay time, stratification ratio, turbulence intensity, fuel injection pressure, chamber pressure, chamber temperature, Exhaust Gas recirculation (EGR) addition, hydrogen addition and equivalence ratio on flame propagation and emission concentrations were analyzed. As a part of this work and for the purpose of control and calibration of high pressure injector, spray development and characteristics including spray tip penetration, spray cone angle and overall equivalence ratio were evaluated under a wide range of fuel injection pressures of 30 to 90 atm and different chamber pressures of 1 to 5 atm. Thermodynamic properties of hydrocarbon/air plasma mixtures at ultra-high temperatures must be precisely calculated due to important influence on the flame kernel formation and propagation in combusting flows and spark discharge applications. A new algorithm based on the statistical thermodynamics was developed to calculate the ultra-high temperature plasma

  11. Image-based in vivo assessment of targeting accuracy of stereotactic brain surgery in experimental rodent models

    NASA Astrophysics Data System (ADS)

    Rangarajan, Janaki Raman; Vande Velde, Greetje; van Gent, Friso; de Vloo, Philippe; Dresselaers, Tom; Depypere, Maarten; van Kuyck, Kris; Nuttin, Bart; Himmelreich, Uwe; Maes, Frederik

    2016-11-01

    Stereotactic neurosurgery is used in pre-clinical research of neurological and psychiatric disorders in experimental rat and mouse models to engraft a needle or electrode at a pre-defined location in the brain. However, inaccurate targeting may confound the results of such experiments. In contrast to the clinical practice, inaccurate targeting in rodents remains usually unnoticed until assessed by ex vivo end-point histology. We here propose a workflow for in vivo assessment of stereotactic targeting accuracy in small animal studies based on multi-modal post-operative imaging. The surgical trajectory in each individual animal is reconstructed in 3D from the physical implant imaged in post-operative CT and/or its trace as visible in post-operative MRI. By co-registering post-operative images of individual animals to a common stereotaxic template, targeting accuracy is quantified. Two commonly used neuromodulation regions were used as targets. Target localization errors showed not only variability, but also inaccuracy in targeting. Only about 30% of electrodes were within the subnucleus structure that was targeted and a-specific adverse effects were also noted. Shifting from invasive/subjective 2D histology towards objective in vivo 3D imaging-based assessment of targeting accuracy may benefit a more effective use of the experimental data by excluding off-target cases early in the study.

  12. Image-based in vivo assessment of targeting accuracy of stereotactic brain surgery in experimental rodent models

    PubMed Central

    Rangarajan, Janaki Raman; Vande Velde, Greetje; van Gent, Friso; De Vloo, Philippe; Dresselaers, Tom; Depypere, Maarten; van Kuyck, Kris; Nuttin, Bart; Himmelreich, Uwe; Maes, Frederik

    2016-01-01

    Stereotactic neurosurgery is used in pre-clinical research of neurological and psychiatric disorders in experimental rat and mouse models to engraft a needle or electrode at a pre-defined location in the brain. However, inaccurate targeting may confound the results of such experiments. In contrast to the clinical practice, inaccurate targeting in rodents remains usually unnoticed until assessed by ex vivo end-point histology. We here propose a workflow for in vivo assessment of stereotactic targeting accuracy in small animal studies based on multi-modal post-operative imaging. The surgical trajectory in each individual animal is reconstructed in 3D from the physical implant imaged in post-operative CT and/or its trace as visible in post-operative MRI. By co-registering post-operative images of individual animals to a common stereotaxic template, targeting accuracy is quantified. Two commonly used neuromodulation regions were used as targets. Target localization errors showed not only variability, but also inaccuracy in targeting. Only about 30% of electrodes were within the subnucleus structure that was targeted and a-specific adverse effects were also noted. Shifting from invasive/subjective 2D histology towards objective in vivo 3D imaging-based assessment of targeting accuracy may benefit a more effective use of the experimental data by excluding off-target cases early in the study. PMID:27901096

  13. Can a graft be placed over a flap in complex hypospadias surgery? An experimental study in rabbits

    PubMed Central

    de Mattos, Ricardo Marcondes; de Araújo, Sérgio R.R.; Quitzan, Juliany Gomes; Leslie, Bruno; Bacelar, Herick; Parizi, João Luiz Gomes; Caetano Martins, Gustavo Marconi; da Cruz, Marcela Leal; Macedo, Antonio

    2016-01-01

    ABSTRACT Purpose: To develop a rabbit experimental study to test the hypothesis that surgical repair of hypospadias with severe ventral curvatures might be completed in one stage, if a graft, such as buccal mucosa, could be placed over the tunica vaginalis flap used in corporoplasty for ventral lengthening, with the addition of an onlay preputial island flap to complete the urethroplasty. Materials and methods: The experimental procedure with rabbits included a tunica vaginalis flap for reconstruction of the corpora after corporotomy, simulating a ventral lengthening operation. A buccal mucosa graft was placed directly on top of the flap, and the urethroplasty was completed with an onlay preputial island flap. Eight rabbits were divided into 4 groups, sacrificed at 2, 4, 8 and 12 weeks postoperatively, and submitted to histological evaluation. Results: We observed a large number of complications, such as fistula (75%), urinary retention (50%) and stenosis (50%). There were two deaths related to the procedure. Histological evaluation demonstrated a severe and persistent inflammatory reaction. No viable tunica vaginalis or buccal mucosa was identified. Conclusions: In this animal model, the association of a buccal mucosa graft over the tunica vaginalis flap was not successful, and resulted in complete loss of both tissues. PMID:27649106

  14. [What Must the (Abdominal) Surgeon Know about Experimental Medicine (?) - Translational Research in General (Abdominal) Surgery(Viszeral-)Chirurg & experimentelle Medizin].

    PubMed

    Wex, T; Kuester, D; Meyer, F

    2015-08-01

    Experimental medicine has evolved tremendously in the last few years. In particular, the introduction of novel techniques, in-vitro models, knock-out/transgenic animals and high-through put analytical methodologies have resulted in a deeper understanding of cellular pathophysiology and diseases. The daily clinical management has benefited by the introduction of biomarkers and targeted therapies. This development has been accompanied by increasing specialisation across all fields of research and medicine. Therefore, clinical-translational research requires a team of competent partners nowadays. The visceral surgeon can contribute significantly to these projects. The present review highlights several aspects of translational research and put chances and potential pitfalls into perspective in context with the work of the visceral surgeon.

  15. Lung surgery

    MedlinePlus

    ... are thoracotomy and video-assisted thoracoscopic surgery (VATS). Robotic surgery may also be used. Lung surgery using a ... clot from the pulmonary artery ( pulmonary embolism ) Treat complications of tuberculosis Video-assisted thoracoscopic surgery can be used to treat many of these ...

  16. Development and trial manufacturing of 1/2-scale partial mock-up of blanket box structure for fusion experimental reactor

    NASA Astrophysics Data System (ADS)

    Hashimoto, Toshiyuki; Takatsu, Hideyuki; Sato, Satoshi

    1994-07-01

    Conceptual design of breeding blanket has been discussed during the CDA (Conceptual Design Activities) of ITER (International Thermonuclear Experimental Reactor). Structural concept of breeding blanket is based on box structure integrated with first wall and shield, which consists of three coolant manifolds for first wall, breeding and shield regions. The first wall must have cooling channels to remove surface heat flux and nuclear heating. The box structure includes plates to form the manifolds and stiffening ribs to withstand enormous electromagnetic load, coolant pressure and blanket internal (purge gas) pressure. A 1/2-scale partial model of the blanket box structure for the outboard side module near midplane is manufactured to estimate the fabrication technology, i.e. diffusion bonding by HIP (Hot Isostatic Pressing) and EBW (Electron Beam Welding) procedure. Fabrication accuracy is a key issue to manufacture first wall panel because bending deformation during HIP may not be small for a large size structure. Data on bending deformation during HIP was obtained by preliminary manufacturing of HIP elements. For the shield structure, it is necessary to reduce the welding strain and residual stress of the weldment to establish the fabrication procedure. Optimal shape of the parts forming the manifolds, welding locations and welding sequence have been investigated. In addition, preliminary EBW tests have been performed in order to select the EBW conditions, and fundamental data on built-up shield have been obtained. Especially, welding deformation by joining the first wall panel to the shield has been measured, and total deformation to build-up shield by EBW has been found to be smaller than 2 mm. Consequently, the feasibility of fabrication technologies has been successfully demonstrated for a 1m-scaled box structure including the first wall with cooling channels by means of HIP, EBW and TIG (Tungsten Inert Gas arc)-welding.

  17. Partial arthrodeses of the wrist.

    PubMed

    Marcuzzi, A; Cristiani, G; Castagnini, L; Castagnetti, C; Caroli, A

    1995-01-01

    The authors report 16 cases of partial arthrodeses of the wrist for the treatment of Kienboeck's disease, pseudarthrosis of the scaphoid, rotatory subluxation of the scaphoid, rheumatoid arthritis, etc. Based on the good results obtained (76.6%) the authors believe that partial arthrodeses constitute the type of treatment indicated for the treatment of pathologies that involve only some of the carpal bones, and they also emphasize that this type of surgery represents a valid alternative to total arthrodesis of the wrist.

  18. Maze Surgery

    MedlinePlus

    ... surgery to treat an arrhythmia called chronic atrial fibrillation (AF). AF is a fast, irregular heart rhythm ... Surgeons http://www.sts.org/node/2275 Atrial Fibrillation Surgery – Maze Procedure Updated August 2016 Please contact ...

  19. Turbinate surgery

    MedlinePlus

    Turbinectomy; Turbinoplasty; Turbinate reduction; Nasal airway surgery ... There are several types of turbinate surgery: Turbinectomy: All or part of the lower turbinate is taken out. This can be done in several different ways, but sometimes a ...

  20. After Surgery

    MedlinePlus

    ... side effects. There is usually some pain with surgery. There may also be swelling and soreness around ... the first few days, weeks, or months after surgery. Some other questions to ask are How long ...

  1. Laparoscopic partial splenic resection.

    PubMed

    Uranüs, S; Pfeifer, J; Schauer, C; Kronberger, L; Rabl, H; Ranftl, G; Hauser, H; Bahadori, K

    1995-04-01

    Twenty domestic pigs with an average weight of 30 kg were subjected to laparoscopic partial splenic resection with the aim of determining the feasibility, reliability, and safety of this procedure. Unlike the human spleen, the pig spleen is perpendicular to the body's long axis, and it is long and slender. The parenchyma was severed through the middle third, where the organ is thickest. An 18-mm trocar with a 60-mm Endopath linear cutter was used for the resection. The tissue was removed with a 33-mm trocar. The operation was successfully concluded in all animals. No capsule tears occurred as a result of applying the stapler. Optimal hemostasis was achieved on the resected edges in all animals. Although these findings cannot be extended to human surgery without reservations, we suggest that diagnostic partial resection and minor cyst resections are ideal initial indications for this minimally invasive approach.

  2. Effect of Catechol-O-methyltransferase-gene (COMT) Variants on Experimental and Acute Postoperative Pain in 1,000 Women undergoing Surgery for Breast Cancer

    PubMed Central

    Kambur, Oleg; Kaunisto, Mari A.; Tikkanen, Emmi; Leal, Suzanne M.; Ripatti, Samuli; Kalso, Eija A.

    2016-01-01

    Background Catechol-O-methyltransferase (COMT) metabolizes catecholamines in different tissues. Polymorphisms in COMT gene can attenuate COMT activity and increase sensitivity to pain. Human studies exploring the effect of COMT polymorphisms on pain sensitivity have mostly included small, heterogeneous samples and have ignored several important single nucleotide polymorphisms (SNPs). This study examines the effect of COMT polymorphisms on experimental and postoperative pain phenotypes in a large ethnically homogeneous female patient cohort. Methods Intensity of cold (+2–4°C) and heat (+48°C) pain and tolerance to cold pain were assessed in 1,000 patients scheduled for breast cancer surgery. Acute postoperative pain and oxycodone requirements were recorded. Twenty-two COMT SNPs were genotyped and their association with six pain phenotypes analyzed with linear regression. Results There was no association between any of the tested pain phenotypes and SNP rs4680. The strongest association signals were seen between rs165774 and heat pain intensity as well as rs887200 and cold pain intensity. In both cases, minor allele carriers reported less pain. Neither of these results remained significant after strict multiple testing corrections. When analyzed further, the effect of rs887200 was, however, shown to be significant and consistent throughout the cold pressure test. No evidence of association between the SNPs and postoperative oxycodone consumption was found. Conclusions SNPs rs887200 and rs165774 located in the untranslated regions of the gene had the strongest effects on pain sensitivity. Their effect on pain is described here for the first time. These results should be confirmed in further studies and the potential functional mechanisms of the variants studied. PMID:24343288

  3. [Voice function in patients after partial laryngectomy].

    PubMed

    Kosztyła-Hojna, B; Chodynicki, S; Lazarczyk, B; Tupalska, M; Mikiel, W

    1998-01-01

    103 patients with cancer of the larynx treated with partial laryngectomy were presented. Voice quality before and after surgery was compared. Voice was analysed by subjective and objective-spectrographic methods. Partial laryngectomies consisted of: vertical, horizontal and supraglottic subtotal procedures. The least dysphony was found in horizontal laryngectomy, the biggest--in supraglottic subtotal laryngectomy.

  4. Coupler for surgery on small animals

    NASA Technical Reports Server (NTRS)

    Johnson, J. E., Jr.; Swartz, P. F.

    1979-01-01

    Minicoupler simplifies exchange of fluids with organs of laboratory animals enabling one person to perform surgery on experimental animals such as rats and mice. Innovation eliminates obstructing hands and instruments from areas of surgery.

  5. [Facial surgery].

    PubMed

    Meningaud, Jean-Paul

    2010-11-20

    The patient who has to sustain facial surgery is doubly concerned by the functional issues of his case and his cosmetic appearance. Fortunately, in the recent period of time, huge advancements have been done permitting to offer a solution in more and more difficult situations. The aim of the present article is to give a panorama of facial plastic surgery for non-specialized physicians. The main aspects of the specialty are approached through the surgical techniques born from the progress of technology and biology. This paper treats issues of orthognatic surgery, endoscopic techniques, osteogenic distraction, different types of graft, cosmetic surgery, skin expander-balloons.

  6. Laparoscopic partial adrenalectomy.

    PubMed

    Ikeda, Y; Takami, H; Tajima, G; Sasaki, Y; Takayama, J; Kurihara, H; Niimi, M

    2002-01-01

    Since corticosteroids are indispensable hormones, partial or cortical-sparing adrenalectomies may be adopted for the surgical treatment of adrenal diseases. In this article, we describe the technique and results of these procedures. Laparoscopic partial or cortical-sparing adrenalectomy has been performed in 10 patients. Seven cases had an aldosterone-producing adenoma (APA) and three had a pheochromocytoma. Three cases with an APA and a case with a pheochromocytoma had tumors located far from the adrenal central vein, and the vein could be preserved. Four cases with an APA and two with a pheochromocytoma had tumors located close to the adrenal central vein, and it was necessary to section the central vein to resect them. All endoscopic procedures were performed successfully. There were no postoperative complications. At follow-up, adrenal 131I-adosterol scintigrams showed the preservation of remnant adrenal function in all patients. Laparoscopic partial or cortical-sparing adrenal surgery was safely performed, and adrenal function was preserved irrespective of whether the adrenal central vein could be preserved or not. We consider this to be a useful operative technique for selected cases.

  7. Laparoscopic surgery - series (image)

    MedlinePlus

    ... performed laparoscopically, including gallbladder removal (laparoscopic cholecystectomy), esophageal surgery (laparoscopic fundoplication), colon surgery (laparoscopic colectomy), and surgery on ...

  8. Rhabdomyosarcoma: Surgery

    MedlinePlus

    ... is and what type of operation is done. Physical changes after surgery can range from little more than a scar to changes in appearance or in how some parts of the body function, which may require physical rehabilitation. For more on surgery as a treatment ...

  9. [Cutaneous surgery workshop].

    PubMed

    Purim, Kátia Sheylla Malta

    2010-08-01

    The training of physician request knowledge, skills and attitudes for the effective exercise of professional practice. The training of basic surgical techniques, used in outpatient procedures, will prepare students to work in different scenarios. This work presents a proposal for teaching through workshops for cutaneous surgery in an experimental model.

  10. Refractive Surgery

    PubMed Central

    Kellum, Keith

    2000-01-01

    The concept of surgically altering the eye to correct refractive errors has been considered for hundreds of years, but only in the past 60 years has interest grown considerably due to the development of modern refractive surgery techniques such as astigmatic keratotomies to correct astigmatism induced by cataract surgery and future technologies currently being investigated. Modern refractive surgery is more involved than setting the correct parameters on the laser. Patient selection and examination, proper technique, and postoperative follow-up for potential complications are essential for a successful refractive procedure. Critical evaluation of new techniques is vital to avoid the pitfall of overly exuberant enthusiasm for new and unproven methods of refractive surgery. Kellum K. Refractive surgery. The Ochsner Journal 2000; 2:164-167. PMID:21765686

  11. Evaluation of ketamine, nimodipine, gabapentin and imipramine in partial sciatic nerve transection model of neuropathic pain in rat: an experimental study.

    PubMed

    Hota, D; Bansal, V; Pattanaik, S

    2007-09-01

    The aim of this research is to study the effects of nimodipine, gabapentin, ketamine and imipramine in the partial sciatic nerve transection (PST) model of neuropathic pain in rats. PST was produced in young Wistar rats of either sex by partial destruction of the sciatic nerve. A decrease in the latency to paw withdrawal reaction on the hot plate was considered as development of neuropathy. The drugs were given daily from the third day of the procedure, and evaluation was done on days 7, 14, 21 and 28. There was a significant decrease (p < 0.05) in the paw withdrawal response in the nimodipine group from day 14 onward when compared with the control group. In the ketamine and imipramine group, this response was seen from day 21 onward. The effect persisted till the end of the study. There was no improvement in the gabapentin group. The results of our study show that nimodipine (dihydropyridine calcium channel blocker), ketamine (NMDA antagonist) and imipramine (tricyclic antidepressant) modulated hyperalgesia and allodynia in the PST model of neuropathy. Gabapentin (an alpha-2 delta calcium subunit blocker) did not show any effect in this model of neuropathy. The widespread use of gabapentin in various types of neuropathic pain thus needs to be reevaluated.

  12. Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

    NASA Astrophysics Data System (ADS)

    Nirmala, D. B.; Raviraj, S.

    2016-06-01

    This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering "Nominal the better" situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

  13. Mesenchymal Stem Cells Transplantation following Partial Hepatectomy: A New Concept to Promote Liver Regeneration—Systematic Review of the Literature Focused on Experimental Studies in Rodent Models

    PubMed Central

    Katselis, Charalambos; Apostolou, Konstantinos; Feretis, Themistoklis; Lymperi, Maria; Konstadoulakis, Manousos M.; Zografos, George C.

    2017-01-01

    Mesenchymal stem cells (MSCs) are an attractive source for regenerative medicine because they are easily accessible through minimally invasive methods and have the potential to enhance liver regeneration (LG) and improve liver function, following partial hepatectomy (PH) and acute or chronic liver injury. A systematic review of the literature was conducted for articles published up to September 1st, 2016, using the MEDLINE database. The keywords that were used in various combinations were as follows: “Mesenchymal stem cells”, “transplantation”, “stem cells”, “adipose tissue derived stem cells”, “bone marrow-derived stem cells”, “partial hepatectomy”, “acute liver failure”, “chronic liver failure”, “liver fibrosis”, “liver cirrhosis”, “rats”, “mice”, and “liver regeneration”. All introduced keywords were searched for separately in MeSH Database to control relevance and terminological accuracy and validity. A total of 41 articles were identified for potential inclusion and reviewed in detail. After a strict selection process, a total of 28 articles were excluded, leaving 13 articles to form the basis of this systematic review. MSCs transplantation promoted LG and improved liver function. Furthermore, MSCs had the ability to differentiate in hepatocyte-like cells, increase survival, and protect hepatocytes by paracrine mechanisms. MSCs transplantation may provide beneficial effects in the process of LG after PH and acute or chronic liver injury. They may represent a new therapeutic option to treat posthepatectomy acute liver failure. PMID:28386285

  14. Delivery of antifibroblast agents as adjuncts to filtration surgery. Part I--Periocular clearance of cobalt-57 bleomycin in experimental drug delivery: pilot study in the rabbit

    SciTech Connect

    Kay, J.S.; Litin, B.S.; Woolfenden, J.M.; Chvapil, M.; Herschler, J.

    1986-10-01

    Antitumor and antifibroblast agents show promise as adjuncts after glaucoma filtration surgery in reducing postoperative scarring and failure. We used nuclear imaging in rabbits to investigate periocular clearance of one such agent (/sup 57/Co-bleomycin). Sub-Tenon injection was compared to other delivery techniques. Our results showed that a collagen sponge and a silastic disc implant with a microhole prolonged drug delivery when compared to sub-Tenon injection alone or injection with a viscosity enhancing agent (0.5% sodium hyaluronate). We theorize that if an antifibroblast agent can be delivered in small and sustained amounts after filtration surgery, this may prolong bleb longevity and avoid unnecessary drug toxicity.

  15. Virtual reality in laparoscopic surgery.

    PubMed

    Uranüs, Selman; Yanik, Mustafa; Bretthauer, Georg

    2004-01-01

    Although the many advantages of laparoscopic surgery have made it an established technique, training in laparoscopic surgery posed problems not encountered in conventional surgical training. Virtual reality simulators open up new perspectives for training in laparoscopic surgery. Under realistic conditions in real time, trainees can tailor their sessions with the VR simulator to suit their needs and goals, and can repeat exercises as often as they wish. VR simulators reduce the number of experimental animals needed for training purposes and are suited to the pursuit of research in laparoscopic surgery.

  16. Experimental investigations of a partial Ru-O bond during the metal-ligand bifunctional addition in Noyori-type enantioselective ketone hydrogenation.

    PubMed

    Takebayashi, Satoshi; Dabral, Nupur; Miskolzie, Mark; Bergens, Steven H

    2011-06-29

    The transition state for the metal-ligand bifunctional addition step in Noyori's enantioselective ketone hydrogenation was investigated using intramolecular trapping experiments. The bifunctional addition between the Ru dihydride trans-[Ru((R)-BINAP)(H)(2)((R,R)-dpen)] and the hydroxy ketone 4-HOCH(2)C(6)H(4)(CO)CH(3) at -80 °C exclusively formed the corresponding secondary ruthenium alkoxide trans-[Ru((R)-BINAP)(H)(4-HOCH(2)C(6)H(4)CH(CH(3))O)((R,R)-dpen)]. Combined with the results of control experiments, this observation provides strong evidence for the formation of a partial Ru-O bond in the transition state.

  17. Experts' understanding of partial derivatives using the partial derivative machine

    NASA Astrophysics Data System (ADS)

    Roundy, David; Weber, Eric; Dray, Tevian; Bajracharya, Rabindra R.; Dorko, Allison; Smith, Emily M.; Manogue, Corinne A.

    2015-12-01

    [This paper is part of the Focused Collection on Upper Division Physics Courses.] Partial derivatives are used in a variety of different ways within physics. Thermodynamics, in particular, uses partial derivatives in ways that students often find especially confusing. We are at the beginning of a study of the teaching of partial derivatives, with a goal of better aligning the teaching of multivariable calculus with the needs of students in STEM disciplines. In this paper, we report on an initial study of expert understanding of partial derivatives across three disciplines: physics, engineering, and mathematics. We report on the central research question of how disciplinary experts understand partial derivatives, and how their concept images of partial derivatives differ, with a focus on experimentally measured quantities. Using the partial derivative machine (PDM), we probed expert understanding of partial derivatives in an experimental context without a known functional form. In particular, we investigated which representations were cued by the experts' interactions with the PDM. Whereas the physicists and engineers were quick to use measurements to find a numeric approximation for a derivative, the mathematicians repeatedly returned to speculation as to the functional form; although they were comfortable drawing qualitative conclusions about the system from measurements, they were reluctant to approximate the derivative through measurement. On a theoretical front, we found ways in which existing frameworks for the concept of derivative could be expanded to include numerical approximation.

  18. Brain surgery

    MedlinePlus

    Craniotomy; Surgery - brain; Neurosurgery; Craniectomy; Stereotactic craniotomy; Stereotactic brain biopsy; Endoscopic craniotomy ... cut depends on where the problem in the brain is located. The surgeon creates a hole in ...

  19. Hemorrhoid surgery

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/002939.htm Hemorrhoid surgery To use the sharing features on this page, please enable JavaScript. Hemorrhoids are swollen veins around the anus. They may ...

  20. Plastic Surgery

    MedlinePlus

    ... procedure that can help smooth or camouflage severe acne scars) — sometimes feel more comfortable with their appearance ... procedures teens choose include nose reshaping, ear surgery, acne and acne scar treatment, and breast reduction. previous ...

  1. Cosmetic Surgery

    MedlinePlus

    ... image Body image and your kids Cosmetic surgery Eating disorders Pregnancy and body image Subscribe to Body Image ... Association of America http://www.adaa.org National Eating Disorders Association National Institute of Mental Health Information Center, ...

  2. Foot Surgery

    MedlinePlus

    ... be advised by a podiatrist, depending on your test results or a specific medical condition. Postoperative Care The type of foot surgery performed determines the length and kind of aftercare required ...

  3. Laparoscopic Surgery

    MedlinePlus

    ... surgeon’s perspective, laparoscopic surgery may allow for easier dissection of abdominal scar tissue (adhesions), less surgical trauma, ... on Facebook About ACG ACG Store ACG Patient Education & Resource Center Home GI Health and Disease Recursos ...

  4. [Aesthetic surgery].

    PubMed

    Bruck, Johannes C

    2006-01-01

    The WHO describes health as physical, mental and social well being. Ever since the establishment of plastic surgery aesthetic surgery has been an integral part of this medical specialty. It aims at reconstructing subjective well-being by employing plastic surgical procedures as described in the educational code and regulations for specialists of plastic surgery. This code confirms that plastic surgery comprises cosmetic procedures for the entire body that have to be applied in respect of psychological exploration and selection criteria. A wide variety of opinions resulting from very different motivations shows how difficult it is to differentiate aesthetic surgery as a therapeutic procedure from beauty surgery as a primarily economic service. Jurisdiction, guidelines for professional conduct and ethical codes have tried to solve this question. Regardless of the intention and ability of the health insurances, it has currently been established that the moral and legal evaluation of advertisements for medical procedures depends on their purpose: advertising with the intent of luring patients into cosmetic procedures that do not aim to reconstruct a subjective physical disorder does not comply with a medical indication. If, however, the initiative originates with the patient requesting the amelioration of a subjective disorder of his body, a medical indication can be assumed.

  5. Tennis elbow surgery

    MedlinePlus

    Lateral epicondylitis - surgery; Lateral tendinosis - surgery; Lateral tennis elbow - surgery ... Surgery to repair tennis elbow is usually an outpatient surgery. This means you will not stay in the hospital overnight. You will be given ...

  6. Plastic Surgery Statistics

    MedlinePlus

    ... PRS GO PSN PSEN GRAFT Contact Us News Plastic Surgery Statistics Plastic surgery procedural statistics from the ... Plastic Surgery Statistics 2005 Plastic Surgery Statistics 2016 Plastic Surgery Statistics Stats Report 2016 National Clearinghouse of ...

  7. Heart valve surgery - discharge

    MedlinePlus

    ... surgery - minimally invasive Aortic valve surgery - open Bicuspid aortic valve Endocarditis Heart valve surgery Mitral valve prolapse Mitral valve surgery - minimally invasive Mitral valve surgery - open Pulmonary valve stenosis Smoking - tips on how to quit Patient Instructions ...

  8. Study of hemorheological parameters following partial hepatectomy in rats with chronic aluminium intoxication.

    PubMed

    Contini, María del Carmen; Mahieu, Stella; Bazzoni, Graciela; Bernal, Claudio A; Carnovale, Cristina E

    2006-01-01

    The aim of our work was to analyze the hemorheological parameters following partial hepatectomy in rats with chronic Al-intoxication (Al). Male Wistar rats were randomly assigned into four experimental groups (n=6 each one): Sham (rats subjected to simulated surgery); Al+Sham; Partial Hepatectomy (animals subjected to 65% liver resection) and Al+Partial Hepatectomy. Our results show that both Partial Hepatectomy and Al treatment produce a decrease of plasma cholesterol level, which showed a negative association with Rigidity Index increase (r(s)=-0.6475, p<0.05). The increase of Rigidity Index observed in Partial Hepatectomy, Al+Sham and Al+Partial Hepatectomy could be related to the increase of the proportion of non-discocytic erythrocytes, particularly stomatocytes, which determines a diminution of the Morphological Index. In the Altreated groups, greater changes in Rigidity Index and Morphological Index were observed. The relative viscosity of blood at a standard haematocrit of 40% was increased in Partial Hepatectomy, Al+Sham and Al+Partial Hepatectomy as compared to Sham, due to erythrocyte rigidity. On the other hand, we observed that the increase of plasma fibrinogen concentration correlates with augmentation of plasma viscosity (r(s)=0.689, p=0.004) for all the experimental groups studied. The results indicate that both administration of Al and Partial Hepatectomy induce microcytic hypocromic anaemia in the rats reflected by a significant decrease of haematocrit, mean corpuscular volume and mean corpuscular haemoglobin concentration. From these results, we conclude that in partially hepatectomized, Al-overloaded rats the decrease in erythrocyte deformability may be an important factor leading to the installation of anaemia.

  9. Partially coherent ultrafast spectrography

    PubMed Central

    Bourassin-Bouchet, C.; Couprie, M.-E.

    2015-01-01

    Modern ultrafast metrology relies on the postulate that the pulse to be measured is fully coherent, that is, that it can be completely described by its spectrum and spectral phase. However, synthesizing fully coherent pulses is not always possible in practice, especially in the domain of emerging ultrashort X-ray sources where temporal metrology is strongly needed. Here we demonstrate how frequency-resolved optical gating (FROG), the first and one of the most widespread techniques for pulse characterization, can be adapted to measure partially coherent pulses even down to the attosecond timescale. No modification of experimental apparatuses is required; only the processing of the measurement changes. To do so, we take our inspiration from other branches of physics where partial coherence is routinely dealt with, such as quantum optics and coherent diffractive imaging. This will have important and immediate applications, such as enabling the measurement of X-ray free-electron laser pulses despite timing jitter. PMID:25744080

  10. Partially coherent ultrafast spectrography

    NASA Astrophysics Data System (ADS)

    Bourassin-Bouchet, C.; Couprie, M.-E.

    2015-03-01

    Modern ultrafast metrology relies on the postulate that the pulse to be measured is fully coherent, that is, that it can be completely described by its spectrum and spectral phase. However, synthesizing fully coherent pulses is not always possible in practice, especially in the domain of emerging ultrashort X-ray sources where temporal metrology is strongly needed. Here we demonstrate how frequency-resolved optical gating (FROG), the first and one of the most widespread techniques for pulse characterization, can be adapted to measure partially coherent pulses even down to the attosecond timescale. No modification of experimental apparatuses is required; only the processing of the measurement changes. To do so, we take our inspiration from other branches of physics where partial coherence is routinely dealt with, such as quantum optics and coherent diffractive imaging. This will have important and immediate applications, such as enabling the measurement of X-ray free-electron laser pulses despite timing jitter.

  11. [Endoscopic surgery].

    PubMed

    Rushfeldt, Christian; Pham, Khanh Do-Cong; Aabakken, Lars

    2016-05-01

    Endoscopic surgery of the stomach/gastrointestinal tract was developed in the 1990s in Japan as a minimally invasive method of removing early-stage tumours, using a gastro-/coloscope instead of open or laparoscopic surgery. Its advantages are obvious, in that the patient is spared more major surgery, the hospital saves on resources as well as admission to a ward, and society is spared the costs of days of sickness absence. Endoscopic submucosal dissection is considered the most difficult technique, but it allows for the accurate dissection of large tumours. In 1999, Japanese surgeon Takuji Gotoda and his team were the first to perform these types of dissections of early cancers in the rectum using a diathermic needle and a flexible scope.

  12. [Foreskin surgery].

    PubMed

    Kolehmainen, Maija; Taskinen, Seppo; Ossi, Lindell

    2010-01-01

    Balanitis, phimosis and foreskin adhesions are common indications for foreskin surgery during childhood. In phimosis, the foreskin cannot be drawn behind the glans penis because of the narrow external opening of the former. It is important to be able to distinguish between physiologic and pathologic phimosis, since their treatment is different. In adulthood, the need for surgery can be caused by phimosis, a difficult sequel of paraphimosis, recurrent inflammations of the glans penis and foreskin, diseases and cancers of the skin as well as difficulties at intercourse due to the shortness of the frenulum of the prepuce of the penis.

  13. Acne Surgery

    PubMed Central

    Dilworth, G. R.

    1983-01-01

    Acne surgery consists of comedone extraction of non-inflamed lesions, triamcinolone acetate injections of some inflamed lesions, and extraction of milia. Prevention is a very important part of comedone treatment, especially avoidance of picking, moisturizers and harsh soaps. Instruments are also very important: even the finest may be too thick and may have to be filed down. Acne surgery is only an adjunct of good medical therapy. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7 PMID:21283373

  14. Replantation surgery.

    PubMed

    Sabapathy, S Raja; Venkatramani, Hari; Bharathi, R Ravindra; Bhardwaj, Praveen

    2011-06-01

    The current concepts of replantation surgery, a procedure that has been practiced for half a century, can be discussed in terms of patients' demands and expectations, present indications for the procedure, available evidence that influences decision making, and technical refinements practiced to produce better outcomes.

  15. Cardiac Surgery

    PubMed Central

    Weisse, Allen B.

    2011-01-01

    Well into the first decades of the 20th century, medical opinion held that any surgical attempts to treat heart disease were not only misguided, but unethical. Despite such reservations, innovative surgeons showed that heart wounds could be successfully repaired. Then, extracardiac procedures were performed to correct patent ductus arteriosus, coarctation of the aorta, and tetralogy of Fallot. Direct surgery on the heart was accomplished with closed commissurotomy for mitral stenosis. The introduction of the heart-lung machine and cardiopulmonary bypass enabled the surgical treatment of other congenital and acquired heart diseases. Advances in aortic surgery paralleled these successes. The development of coronary artery bypass grafting greatly aided the treatment of coronary heart disease. Cardiac transplantation, attempts to use the total artificial heart, and the application of ventricular assist devices have brought us to the present day. Although progress in the field of cardiovascular surgery appears to have slowed when compared with the halcyon times of the past, substantial challenges still face cardiac surgeons. It can only be hoped that sufficient resources and incentive can carry the triumphs of the 20th century into the 21st. This review covers past developments and future opportunities in cardiac surgery. PMID:22163121

  16. Nose Surgery

    MedlinePlus

    ... requests or policy questions to our media and public relations staff at newsroom@entnet.org . Improving Form And Function Of The Nose Each year thousands of people undergo surgery of the ... plan to avoid appearing in public for about a week due to swelling and ...

  17. Experimental determination of dissolved CO2 content in nominally anhydrous andesitic melts at graphite/diamond saturation - Remobilization of deeply subducted reduced carbon via partial melts of MORB-like eclogite

    NASA Astrophysics Data System (ADS)

    Eguchi, J.; Dasgupta, R.

    2015-12-01

    Experimental phase relations of carbonated lithologies [1] and geochemistry of deep diamonds [2] suggest that deep recycling of carbon has likely been efficient for a significant portion of Earth's history. Both carbonates and organic carbon subduct into the mantle, but with gradual decrease of fO2 with depth [3] most carbon in deep mantle rocks including eclogite could be diamond/graphite [4]. Previous studies investigated the transfer of CO2 from subducted eclogite to the ambient mantle by partial melting in the presence of carbonates, i.e., by generation of carbonate-rich melts [5]. However, the transfer of carbon from subducted eclogite to the mantle can also happen, perhaps more commonly, by extraction of silicate partial melt in the presence of reduced carbon; yet, CO2 solubility in eclogite-derived andesitic melt at graphite/diamond saturation remains unconstrained. CO2content of eclogite melts is also critical as geochemistry of many ocean island basalts suggest the presence of C and eclogite in their source regions [6]. In the present study we determine CO2 concentration in a model andesitic melt [7] at graphite/diamond saturation at conditions relevant for partial melting of eclogite in the convecting upper mantle. Piston cylinder and multi anvil experiments were conducted at 1-6 GPa and 1375-1550 °C using Pt/Gr double capsules. Oxygen fugacity was monitored with Pt-Fe sensors in the starting mix. Completed experiments at 1-3 GPa show that CO2 concentration increases with increasing P, T, and fO2 up to ~0.3 wt%. Results were used to develop empirical and thermodynamic models to predict CO2 concentration in partial melts of graphite saturated eclogite. This allowed us to quantify the extent to which CO2 can mobilize from eclogitic heterogeneities at graphite/diamond saturated conditions. With estimates of eclogite contribution to erupted basaltic lavas, the models developed here allow us to put constraints on the flux of CO2 to mantle source regions

  18. Prohemostatic interventions in liver surgery.

    PubMed

    Stellingwerff, Menno; Brandsma, Amarins; Lisman, Ton; Porte, Robert J

    2012-04-01

    Surgical procedures of the liver, such as partial liver resections and liver transplantation, are major types of abdominal surgery. Liver surgery can be associated with excessive intraoperative blood loss, not only because the liver is a highly vascularized organ, but also because it plays a central role in the hemostatic system. Intraoperative blood loss and transfusion of blood products have been shown to be negatively associated with postoperative outcome after liver surgery. Dysfunction of the liver is frequently accompanied with a dysfunctional hemostatic system. However, in general, there is a poor correlation between preoperative coagulation tests and the intraoperative bleeding risk in patients undergoing liver surgery. Strategies to avoid excessive blood loss in liver surgery have been an active field of research and include three different areas: surgical methods, anesthesiological methods, and pharmacological agents.Surgeons can minimize blood loss by clamping the hepatic vasculature, by using specific dissection devices, and by using topical hemostatic agents. Anesthesiologists play an important role in minimizing blood loss by avoiding intravascular fluid overload. Maintaining a low central venous pressure has shown to be very effective in reducing blood loss during partial liver resections. Prophylactic transfusion of blood products such as fresh frozen plasma (FFP) has not been shown to reduce intraoperative bleeding and even seems counterproductive as it results in an increase of the intravascular filling status, which may enhance the bleeding risk. In patients with liver cirrhosis, there is increasing evidence that factors such as portal hypertension and the hyperdynamic circulation play a more important role in the bleeding tendency than changes in the coagulation system. Therefore, intravenous fluid restriction rather than prophylactic administration of large volumes of blood products (i.e., FFP) is recommended in patients undergoing major liver

  19. Experimental Study of Dehydration and Partial Melting of Biotite-Amphibole Gneiss Under Influence of the H2O-CO2-(K, Na)cl Fluids at 5.5 Kbar and 750 and 800 C

    NASA Astrophysics Data System (ADS)

    Safonov, O.; Kosova, S.

    2012-12-01

    Chloride-rich brines coexisting with CO2-rich fluids are an important agent of high-grade metamorphism and metasomatism in the lower to middle crust. Thermodynamic and transport properties of the chloride-rich fluids are well constrained both theoretically and experimentally. Nevertheless, their effects on complex natural assemblages are poorly understood and demand systematic experimental study. We report results of the experiments on interaction of the biotite-amphibole gneiss from the Sand River formation (Limpopo Complex, South Africa) with the H2O-CO2, H2O-CO2-KCl, H2O-CO2-NaCl, and H2O-CO2-(K, Na)Cl fluids at 5.5 kbar, 750 and 800 C, the chloride/(H2O+CO2) ratio varying from 0 to 0.1, and molar CO2/(CO2+H2O) = 0.5. Experiments were carried out using internally-heated gas pressure vessel. Major purposes of the experiments were to trace changes in phase assemblages in dependence on temperature, salt concentration in a fluid, KCl/NaCl ratio and to show a possibility for partial melting. Heating of the gneiss both at 750 and 800 C without any fluid produced no visible changes in its phase assemblage. Interaction of the gneiss with the H2O-CO2 fluid at 750 C did not significantly influence on its phase assemblage, as well. Addition of KCl in the H2O-CO2 fluid at 750 C resulted in the formation of reaction textures consisting of clinopyroxene and K-feldspar around biotite and amphibole at the contacts with plagioclase. No evidence for partial melting was detected in the samples interacted with the H2O-CO2 and H2O-CO2-KCl fluids at 750 C. Addition of NaCl provokes melting with formation of trachytic and trachyandesitic melts along with the new assemblages Cpx+Kfs+Pl+Ti-Mt and Cpx+Amp+Pl+Ti-Mt. Characteristic of feature of amphiboles, forming in the NaCl-rich fluids is their elevated Na2O content. Products of the runs at 750 C do not contain orthopyroxene. This phase appears at 800 C as a result of biotite breakdown in presence of the H2O-CO2 fluid. It is accompanied

  20. Heart bypass surgery

    MedlinePlus

    Off-pump coronary artery bypass; OPCAB; Beating heart surgery; Bypass surgery - heart; CABG; Coronary artery bypass graft; Coronary artery bypass surgery; Coronary bypass surgery; Coronary artery disease - CABG; CAD - CABG; Angina - ...

  1. Surgery for Breast Cancer

    MedlinePlus

    ... Pregnancy Breast Cancer Breast Cancer Treatment Surgery for Breast Cancer Surgery is a common treatment for breast cancer, ... Relieve symptoms of advanced cancer Surgery to remove breast cancer There are two main types of surgery to ...

  2. Lung Carcinoid Tumor: Surgery

    MedlinePlus

    ... Tumor Treating Lung Carcinoid Tumors Surgery to Treat Lung Carcinoid Tumors Surgery is the main treatment for ... often be cured by surgery alone. Types of lung surgery Different operations can be used to treat ( ...

  3. Refractive corneal surgery - discharge

    MedlinePlus

    Nearsightedness surgery - discharge; Refractive surgery - discharge; LASIK - discharge; PRK - discharge ... You had refractive corneal surgery to help improve your vision. This surgery uses a laser to reshape your cornea. It corrects mild-to-moderate nearsightedness, ...

  4. Comprehensive review on endonasal endoscopic sinus surgery

    PubMed Central

    Weber, Rainer K.; Hosemann, Werner

    2015-01-01

    Endonasal endoscopic sinus surgery is the standard procedure for surgery of most paranasal sinus diseases. Appropriate frame conditions provided, the respective procedures are safe and successful. These prerequisites encompass appropriate technical equipment, anatomical oriented surgical technique, proper patient selection, and individually adapted extent of surgery. The range of endonasal sinus operations has dramatically increased during the last 20 years and reaches from partial uncinectomy to pansinus surgery with extended surgery of the frontal (Draf type III), maxillary (grade 3–4, medial maxillectomy, prelacrimal approach) and sphenoid sinus. In addition there are operations outside and beyond the paranasal sinuses. The development of surgical technique is still constantly evolving. This article gives a comprehensive review on the most recent state of the art in endoscopic sinus surgery according to the literature with the following aspects: principles and fundamentals, surgical techniques, indications, outcome, postoperative care, nasal packing and stents, technical equipment. PMID:26770282

  5. Image-guided spine surgery: state of the art and future directions

    PubMed Central

    Shafizadeh, Sven; Rixen, Dieter; Paffrath, Thomas; Bouillon, Bertil; Steinhausen, Eva S.; Baethis, Holger

    2009-01-01

    Navigation technology is a widely available tool in spine surgery and has become a part of clinical routine in many centers. The issue of where and when navigation technology should be used is still an issue of debate. It is the aim of this study to give an overview on the current knowledge concerning the technical capabilities of image-guided approaches and to discuss possible future directions of research and implementation of this technique. Based on a Medline search total of 1,462 publications published until October 2008 were retrieved. The abstracts were scanned manually for relevance to the topics of navigated spine surgery in the cervical spine, the thoracic spine, the lumbar spine, as well as ventral spine surgery, radiation exposure, tumor surgery and cost-effectivity in navigated spine surgery. Papers not contributing to these subjects were deleted resulting in 276 papers that were included in the analysis. Image-guided approaches have been investigated and partially implemented into clinical routine in virtually any field of spine surgery. However, the data available is mostly limited to small clinical series, case reports or retrospective studies. Only two RCTs and one metaanalysis have been retrieved. Concerning the most popular application of image-guided approaches, pedicle screw insertion, the evidence of clinical benefit in the most critical areas, e.g. the thoracic spine, is still lacking. In many other areas of spine surgery, e.g. ventral spine surgery or tumor surgery, image-guided approaches are still in an experimental stage. The technical development of image-guided techniques has reached a high level as the accuracies that can be achieved technically meet the anatomical demands. However, there is evidence that the interaction between the surgeon (‘human factor’) and the navigation system is a source of inaccuracy. It is concluded that more effort needs to be spend to understand this interaction. PMID:19763640

  6. Partial focusing by indefinite complementary metamaterials

    NASA Astrophysics Data System (ADS)

    Cheng, Qiang; Liu, Ruopeng; Mock, Jack J.; Cui, Tie Jun; Smith, David R.

    2008-09-01

    We have experimentally realized a two-dimensional partial focusing within a planar waveguide using complementary indefinite metamaterials. When the electric fields emitted from the dipole are TE polarized, the focusing condition requires negative magnetic response in the propagation direction of the waveguide, which can be achieved by the complementary electric resonator (CELC) structures. We have carefully designed the experimental configurations and the dimensions for the CELC structures. The experimental result is consistent with the theoretical prediction, which validates the partial focusing phenomenon.

  7. Advances in mucogingival surgery.

    PubMed

    Prato, G P

    2000-01-01

    The term Mucogingival Surgery was proposed by Friedman in 1957 to indicate any surgery "designed to preserve attached gingiva, to remove frena or muscle attachment, and to increase the depth of the vestibule". The aim of this type of surgery was to maintain an adequate amount of attached gingiva and to prevent continuous loss of attachment. This philosophy was supported by many horizontal observations in humans that confirmed the need for a certain band of attached gingiva to maintain periodontal tissue in a healthy state. Subsequently, clinical and experimental studies by Wennström and Lindhe (1983) demonstrated that as long as plaque buildup is kept under careful control there is no minimum width of keratinised gingiva necessary to prevent the development of periodontal disease. These observations reduce the importance of Mucogingival Surgery. Surgical techniques are used mostly to solve aesthetic problems, since the term "Periodontal Plastic Surgery" has been suggested to indicate surgical procedures performed to correct or eliminate anatomical, developmental or traumatic deformities of the gingiva or alveolar mucosa. More recently the Consensus Report of the American Academy of Periodontology (1996) defines Mucogingival Therapy as "non surgical and surgical correction of the defects in morphology, position and/or amount of soft tissue and underlying bone". This assigns importance to non-surgical therapy and to the bone condition because of its influence on the morphology of the defects. In this respect the Mucogingival Therapy includes: Root coverage procedures, Gingival augmentation, Augmentation of the edentulous ridge, Removing of the aberrant frenulum, Prevention of ridge collapse associated with tooth extraction, Crown lengthening, Teeth that are not likely to erupt, Loss of interdental papilla which presents an aesthetic and/or phonetic problem.

  8. [Robotic surgery].

    PubMed

    Sándor, József; Haidegger, Tamás; Kormos, Katalin; Ferencz, Andrea; Csukás, Domokos; Bráth, Endre; Szabó, Györgyi; Wéber, György

    2013-10-01

    Due to the fast spread of laparoscopic cholecystectomy, surgical procedures have been changed essentially. The new techniques applied for both abdominal and thoracic procedures provided the possibility for minimally invasive access with all its advantages. Robots - originally developed for industrial applications - were retrofitted for laparoscopic procedures. The currently prevailing robot-assisted surgery is ergonomically more advantageous for the surgeon, as well as for the patient through the more precise preparative activity thanks to the regained 3D vision. The gradual decrease of costs of robotic surgical systems and development of new generations of minimally invasive devices may lead to substantial changes in routine surgical procedures.

  9. Immunological response in laparoscopic surgery.

    PubMed

    Smit, M J; Beelen, R H; Eijsbouts, Q A; Meijer, S; Cuesta, M A

    1996-01-01

    Immunological response to surgical trauma may be protected during laparoscopic surgery. A less surgical trauma, in comparison with conventional surgery, may explained these important advantages. Plasma and macrophages studies have demonstrated that laparoscopic cholecystectomy causes less depression of cell mediated immunity than open cholecystectomy. What will be the impact of this immunological protection in laparoscopic advanced and oncological surgery? Experimental studies have showed that laparoscopic techniques in advanced and oncological surgery may have important advantages concerning the "preservation of the immune status" of the patient. That will imply in the future a lower percentage of infections, local recurrence and even a lower percentage of distant metastases. On the other hand, the appearance of tumor implants in the port sites after laparoscopic resection for cancer is a significant drawback of this procedure. Proper investigations have to be carried out in order to find the cause and the solution of this dilemma.

  10. Bariatric Surgery

    PubMed Central

    2005-01-01

    Executive Summary Objective To conduct an evidence-based analysis of the effectiveness and cost-effectiveness of bariatric surgery. Background Obesity is defined as a body mass index (BMI) of at last 30 kg/m2.1 Morbid obesity is defined as a BMI of at least 40 kg/m2 or at least 35 kg/m2 with comorbid conditions. Comorbid conditions associated with obesity include diabetes, hypertension, dyslipidemias, obstructive sleep apnea, weight-related arthropathies, and stress urinary incontinence. It is also associated with depression, and cancers of the breast, uterus, prostate, and colon, and is an independent risk factor for cardiovascular disease. Obesity is also associated with higher all-cause mortality at any age, even after adjusting for potential confounding factors like smoking. A person with a BMI of 30 kg/m2 has about a 50% higher risk of dying than does someone with a healthy BMI. The risk more than doubles at a BMI of 35 kg/m2. An expert estimated that about 160,000 people are morbidly obese in Ontario. In the United States, the prevalence of morbid obesity is 4.7% (1999–2000). In Ontario, the 2004 Chief Medical Officer of Health Report said that in 2003, almost one-half of Ontario adults were overweight (BMI 25–29.9 kg/m2) or obese (BMI ≥ 30 kg/m2). About 57% of Ontario men and 42% of Ontario women were overweight or obese. The proportion of the population that was overweight or obese increased gradually from 44% in 1990 to 49% in 2000, and it appears to have stabilized at 49% in 2003. The report also noted that the tendency to be overweight and obese increases with age up to 64 years. BMI should be used cautiously for people aged 65 years and older, because the “normal” range may begin at slightly above 18.5 kg/m2 and extend into the “overweight” range. The Chief Medical Officer of Health cautioned that these data may underestimate the true extent of the problem, because they were based on self reports, and people tend to over-report their

  11. Robotic Surgery

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The Automated Endoscopic System for Optimal Positioning, or AESOP, was developed by Computer Motion, Inc. under a SBIR contract from the Jet Propulsion Lab. AESOP is a robotic endoscopic positioning system used to control the motion of a camera during endoscopic surgery. The camera, which is mounted at the end of a robotic arm, previously had to be held in place by the surgical staff. With AESOP the robotic arm can make more precise and consistent movements. AESOP is also voice controlled by the surgeon. It is hoped that this technology can be used in space repair missions which require precision beyond human dexterity. A new generation of the same technology entitled the ZEUS Robotic Surgical System can make endoscopic procedures even more successful. ZEUS allows the surgeon control various instruments in its robotic arms, allowing for the precision the procedure requires.

  12. Endodontic surgery.

    PubMed

    Lieblich, Stuart E

    2012-01-01

    Conventional endodontic therapy is successful approximately 80-85% of the time. Many of these failures will occur after one year. The presence of continued pain, drainage, mobility or an increasing size of a radiolucent area are some of the indications to treat the case surgically. Since many of these cases may have had final restorations placed by the dentist, the salvage of these cases is of importance to the patient. Advances in periapical surgery have included the use of ultrasonic root end preparation. With the use of these piezoelectric devices, a more controlled apical preparation can be achieved. Additionally, isthmus areas between canals can be appropriately prepared and sealed. The precision afforded with these devices reduces the chances for a malpositioned fill and a more successful outcome.

  13. Experimental and Numerical Determination of the Local Temperature Distribution during Phacoemulsification and Comparison of Different Surgery Situations within Enucleated Porcine Eyes.

    PubMed

    Buschschlüter, Steffen; von Eicken, Jörn; Koch, Christian; Höh, Helmut

    2015-08-01

    Phacoemulsification, a common treatment for cataract, is accompanied by cell damage at the corneal endothelium. Thermal exposure during treatment has been considered a reason for this damage, but a thorough experimental and theoretical assessment of the local temperature distribution inside the eye had not yet been conducted. Measurements in porcine eyes and a finite-element simulation enabled such an assessment and localized the highest temperature rise very close to the probe. The results described in this study indicate that a distance of 1 mm between the probe and the endothelium should be maintained during treatment as a safety margin, especially when fluid flow is blocked. The highest measured temperature rise with surgically reasonable system settings and unblocked fluid flow was 1.11°C. The finite-element simulation described here is able to calculate the temperature rise at the endothelium and could serve as a tool for comparing arbitrary surgical situations with respect to thermal exposure of the endothelium.

  14. [Minimally invasive surgery and robotic surgery: surgery 4.0?].

    PubMed

    Feußner, H; Wilhelm, D

    2016-03-01

    Surgery can only maintain its role in a highly competitive environment if results are continuously improved, accompanied by further reduction of the interventional trauma for patients and with justifiable costs. Significant impulse to achieve this goal was expected from minimally invasive surgery and, in particular, robotic surgery; however, a real breakthrough has not yet been achieved. Accordingly, the new strategic approach of cognitive surgery is required to optimize the provision of surgical treatment. A full scale integration of all modules utilized in the operating room (OR) into a comprehensive network and the development of systems with technical cognition are needed to upgrade the current technical environment passively controlled by the surgeon into an active collaborative support system (surgery 4.0). Only then can the true potential of minimally invasive surgery and robotic surgery be exploited.

  15. What Is Heart Surgery?

    MedlinePlus

    ... Another type of heart surgery is called off-pump, or beating heart, surgery. It's like traditional open- ... heart-lung bypass machine isn't used. Off-pump heart surgery is limited to CABG. Surgeons can ...

  16. Dental Implant Surgery

    MedlinePlus

    Dental implant surgery Overview By Mayo Clinic Staff Dental implant surgery is a procedure that replaces tooth roots with ... look and function much like real ones. Dental implant surgery can offer a welcome alternative to dentures ...

  17. Weight Loss Surgery

    MedlinePlus

    ... A Week of Healthy Breakfasts Shyness Weight Loss Surgery KidsHealth > For Teens > Weight Loss Surgery A A ... Risks and Side Effects? What Is Weight Loss Surgery? For some people, being overweight is about more ...

  18. Surgery for Testicular Cancer

    MedlinePlus

    ... type of retroperitoneal lymph node surgery called nerve-sparing surgery that is very successful when done by ... children. These men may wish to discuss nerve-sparing surgery with their doctors, as well as sperm ...

  19. Tennis elbow surgery - discharge

    MedlinePlus

    ... epicondylitis surgery - discharge; Lateral tendinosis surgery - discharge; Lateral tennis elbow surgery - discharge ... long as you are told. This helps ensure tennis elbow will not return. You may be prescribed a ...

  20. Alternative Refractive Surgery Procedures

    MedlinePlus

    ... LASIK Alternative Refractive Surgery Procedures Laser Surgery Recovery Alternative Refractive Surgery Procedures Dec. 12, 2015 Today's refractive ... that releases controlled amounts of radio frequency (RF) energy, instead of a laser, to apply heat to ...

  1. Surgery for pancreatic cancer

    MedlinePlus

    ... medlineplus.gov/ency/article/007649.htm Surgery for pancreatic cancer To use the sharing features on this page, ... surgery are used in the surgical treatment of pancreatic cancer. Whipple procedure: This is the most common surgery ...

  2. Laser surgery - skin

    MedlinePlus

    Surgery using a laser ... used is directly related to the type of surgery being performed and the color of the tissue ... Laser surgery can be used to: Close small blood vessels to reduce blood loss Remove warts , moles , sunspots, and ...

  3. Weight Loss Surgery

    MedlinePlus

    ... serious medical problems. Weight loss surgery (also called bariatric surgery) can help very obese people lose weight. But ... Gastric banding is the simplest of the three weight loss surgeries. People who get it might not lose as ...

  4. Bariatric Surgery Procedures

    MedlinePlus

    ... Center Access to Care Toolkit EHB Access Toolkit Bariatric Surgery Procedures Bariatric surgical procedures cause weight loss by ... minimally invasive techniques (laparoscopic surgery). The most common bariatric surgery procedures are gastric bypass, sleeve gastrectomy, adjustable gastric ...

  5. Gastric Sleeve Surgery

    MedlinePlus

    ... doctors recommend weight loss surgery (also known as bariatric surgery ) for very overweight teens if they've tried ... it is at a children's hospital with a bariatric surgery program that involves a team of specialists. Members ...

  6. Weight Loss Surgery (Bariatric Surgery) (For Parents)

    MedlinePlus

    ... Health Growth & Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & ... Surgery Types of Surgery Gastric Bypass ... or intestines removed due to ulcers or cancer tended to lose a lot of weight after ...

  7. Statistics and Ethics in Surgery and Anesthesia

    ERIC Educational Resources Information Center

    Gilbert, John P.; And Others

    1977-01-01

    Analyzes 46 medical research papers on the effects of innovative versus standard surgical procedures on the health of patients. Results reveal that innovations generally reduce complications. The ethics of experimental surgery are also discussed. (CP)

  8. Partial siamese twin as potential organ donor

    PubMed Central

    Kapoor, Rakesh; Maheshwari, Ruchir; Srivastava, Aneesh; Sharma, Raj K.

    2010-01-01

    During evaluation of a partial Siamese twin for removal of nonviable parasitic part in an 8-year-old male child, a fully functional kidney was found. The functional status of the extra kidney was found to be within acceptable limits for the purpose of transplant, which was subsequently done in a 24-year-old patient with end-stage renal disease. The recipient is healthy 19 months after the surgery. The possibility of using organs from a partial Siamese twin makes this a unique case report. PMID:20877612

  9. [Baldness surgery].

    PubMed

    Dardour, J-C; Hennebert, H

    2003-10-01

    Redistribution from hair-rich to hair-poor areas is the fundamental principle of baldness surgery. Success of hair transplantation is based on the fact that transplanted hair follicles will behave as they did in their original area and continue to grow. Three basic techniques are employed: scalp flaps, scalp reductions and hair grafts. Each technique has undergone considerable refinements answering to initial wrong results and criticisms. The typical doll-hair tufted effect of old macro-grafts has disappeared with micro-graft shift. The unaesthetic cheese-like Hippocratic crown donor defect aspect ended when harvesting a long strip of occipital hair bearing scalp. The posteriorly directed hair growth has disappeared by using superiorly based flaps. Respective indications and tension-free closure ensure that the incidence of necrosis is low. Limited results of old scalp reductions have decreased by testing preoperative laxity of the scalp and using extensive undermining of the scalp. The future may release on medical treatment avoiding dihydrotestosterone to act on genetically predisposed follicles avoiding miniaturization of the hair and baldness development. However, when baldness has appeared, as the hair follicle's culture is not actually effective, the state of art is still to plan a surgical strategy using successive stages of this large panel of techniques to reach a natural effect with the best hair orientation and density.

  10. Partial (focal) seizure

    MedlinePlus

    ... Jacksonian seizure; Seizure - partial (focal); Temporal lobe seizure; Epilepsy - partial seizures ... Abou-Khalil BW, Gallagher MJ, Macdonald RL. Epilepsies. In: Daroff ... Practice . 7th ed. Philadelphia, PA: Elsevier; 2016:chap 101. ...

  11. Partial tooth gear bearings

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  12. Pediatric heart surgery - discharge

    MedlinePlus

    ... get enough calories to heal and grow. After heart surgery, most babies and infants (younger than 12 to 15 months) can take ... valve surgery - children - discharge; Heart surgery - pediatric - discharge; Heart transplant - pediatric - discharge ... open heart surgery References Bernstein D. General principles ...

  13. Maxillary orthognathic surgery.

    PubMed

    Bauer, Richard E; Ochs, Mark W

    2014-11-01

    Maxillary surgery to correct dentofacial deformity has been practiced for almost 100 years. Significant advances have made maxillary surgery a safe and efficient means of correcting midface deformities. Anesthetic techniques, specifically hypotensive anesthesia, have allowed for safer working conditions. Landmark studies have proven manipulation and segmentalization of the maxilla is safe and allowed this surgery to become a mainstay in corrective jaw surgery. This article provides an overview of surgical techniques and considerations as they pertain to maxillary surgery for orthognathic surgery. Segmental surgery, openbite closure, vertical excess, grafting, and a technology update are discussed.

  14. Tissue holder for experimental and Demonstration Surgery

    NASA Technical Reports Server (NTRS)

    Kuchta, F. J.; Pavlik, J. B.; Vargo, D. J.; Winters, G. R.

    1972-01-01

    Development of device for holding anatomical tissues during operations is discussed. Device consists of plastic dish with hemispherical recess in center to hold excised eyes. Low vacuum applied to underside of recess insures holding of part.

  15. Experimental study of local dehydration and partial melting of biotite-amphibole gneiss with participation of the H2O-CO2-(K, Na)Cl fluids at the middle-crustal conditions

    NASA Astrophysics Data System (ADS)

    Safonov, O.; Kozhukhantseva, S.

    2012-04-01

    Activity of aqueous chloride-rich brines coexisting with CO2-rich fluids is identified in many amphibolite and granulite terrains suggesting that this type of fluid is an important agent of high-grade metamorphism in the lower to middle crust (see reviews in Touret, 2009; Newton, Manning, 2010). Although thermodynamic and transport properties of these fluids is well constrained both theoretically and experimentally, their affect on complex natural assemblages is poorly understood and demands systematic experimental study. We report here results of the experiments on interaction of the biotite-amphibole gneiss from the Sand River formation (Limpopo Complex, South Africa) with the fluids H2O-CO2-(K, Na)Cl at 5.5 kbar, 750 and 800 C, the chloride/(H2O+CO2) varying from 0 0.1, and molar CO2/(CO2+H2O) = 0.5. No any reaction textures were identified in the sample interacted with the chloride-free CO2-H2O fluid at 750 C. At this temperature, addition of KCl into the fluid resulted in formation of spectacular reaction textures around biotite (Bt), amphibole (Amp), plagioclase (Pl) and quartz (Qtz) in the starting gneiss. These textures are intergrowths of low-Al clinopyroxene (Cpx) and K-feldspar (Kfs) (sporadically accompanied by ilmenite, sphene and Ti-bearing low-Al mica) corresponding to a progress of the following reactions: Phl + 3An + 18Qtz + 3(K2O in fluid) = 3Di + 7Kfs + (H2O in fluid) and Prg + Ed + 7(K2O in fluid) + 37Qtz + 5An = 9Di + 14Kfs + (2H2O + Na2O in fluid). Local partial melting of the gneiss interacted with KCl-bearing fluids at 750OC was observed only in the run at KCl/(CO2+H2O) = 1/30 and could be caused by local variation of water activity in the sample. Nevertheless, at 800 OC, granitic (>70 wt. % of SiO2) K2O-rich and Cl-bearing melt appears along the grain boundaries in all run samples. This melt produces K-feldspar and clinopyroxene, which are found as euhedral crystals in the glass. Melt films are usually accompanied by K-feldspar microveins

  16. Biofeedback versus physiotherapy in patients with partial weight-bearing.

    PubMed

    Hershko, Erel; Tauber, Chanan; Carmeli, Eli

    2008-05-01

    Medical instructions for partial weight-bearing after lower limb surgery and fractures are commonly given. The techniques for instruction are mainly verbal cues. Our aim was to evaluate the efficiency of a new biofeedback device compared with traditional intervention for gait rehabilitation. After orthopedic surgery, 33 patients, randomly divided into a study group (n = 15) and a control group (n = 18), completed 10 days of a rehabilitation protocol. A significant difference (P<.05) was found between the groups. Study subjects were able to follow weight-bearing instructions better. We suggest that gait rehabilitation is more efficient when biofeedback is used to instruct patients regarding partial weight-bearing.

  17. Open partial nephrectomy in renal cell cancer - Essential or obsolete?

    PubMed

    Anastasiadis, Eleni; O'Brien, Timothy; Fernando, Archana

    2016-12-01

    Since the first partial nephrectomy was first conducted 131 years ago, the procedure has evolved into the gold standard treatment for small renal masses. Over the past decade, with the introduction of minimally invasive surgery, open partial nephrectomy still retains a valuable role in the treatment of complex tumours in challenging clinical situations (e.g. hereditary renal cancer or single kidneys), and enables surgeons to push the boundaries of nephron-sparing surgery. In this article, we consider the origin of the procedure and how it has evolved over the past century, the surgical techniques involved, and the oncological and functional outcomes.

  18. Partial polarization by quantum distinguishability

    NASA Astrophysics Data System (ADS)

    Lahiri, Mayukh; Hochrainer, Armin; Lapkiewicz, Radek; Lemos, Gabriela Barreto; Zeilinger, Anton

    2017-03-01

    We establish that a connection exists between wave-particle duality of photons and partial polarization of a light beam. We perform a two-path lowest-order (single photon) interference experiment and demonstrate both theoretically and experimentally that the degree of polarization of the light beam emerging from an output of the interferometer depends on path distinguishability. In our experiment, we are able to change the quantum state of the emerging photon from a pure state to a fully mixed state without any direct interaction with the photon. Although most lowest-order interference experiments can be explained by classical theory, our experiment has no genuine classical analog. Our results show that a case exists where the cause of partial polarization is beyond the scope of classical theory.

  19. Partial splenic resection using the TA-stapler.

    PubMed

    Uranüs, S; Kronberger, L; Kraft-Kine, J

    1994-07-01

    Since 1987, we have used the TA-stapler for 15 partial resections of the spleen. The cases included 5 second- to third-degree traumatic ruptures, 4 splenic cysts, 3 injuries resulting from accidents during upper-abdominal surgery, 2 diagnostic resections, and 1 intralienal pancreatic cyst. The TA-55 stapler was used 14 times and the TA-90 once. No patient developed postoperative bleeding or required further surgery. Postoperative laboratory chemistry and scintigraphy findings were within the limits indicative of normal function in all cases. The TA-stapler expands the technical possibilities for organ-conserving splenic surgery.

  20. Applications of Computational Modeling in Cardiac Surgery

    PubMed Central

    Lee, Lik Chuan; Genet, Martin; Dang, Alan B.; Ge, Liang; Guccione, Julius M.; Ratcliffe, Mark B.

    2014-01-01

    Although computational modeling is common in many areas of science and engineering, only recently have advances in experimental techniques and medical imaging allowed this tool to be applied in cardiac surgery. Despite its infancy in cardiac surgery, computational modeling has been useful in calculating the effects of clinical devices and surgical procedures. In this review, we present several examples that demonstrate the capabilities of computational cardiac modeling in cardiac surgery. Specifically, we demonstrate its ability to simulate surgery, predict myofiber stress and pump function, and quantify changes to regional myocardial material properties. In addition, issues that would need to be resolved in order for computational modeling to play a greater role in cardiac surgery are discussed. PMID:24708036

  1. Animals in surgery--surgery in animals: nature and culture in animal-human relationship and modern surgery.

    PubMed

    Schlich, Thomas; Mykhalovskiy, Eric; Rock, Melanie

    2009-01-01

    AThis paper looks at the entangled histories of animal-human relationship and modem surgery. It starts with the various different roles animals have in surgery--patients, experimental models and organ providers--and analyses where these seemingly contradictory positions of animals come from historically. The analyses is based on the assumption that both the heterogeneous relationships of humans to animals and modern surgery are the results of fundamentally local, contingent and situated developments and not reducible to large-scale social explanations, such as modernization. This change of perspective opens up a new ways of understanding both phenomena as deeply interwoven with the redrawing of the nature-culture divide.

  2. Complications of Sinus Surgery

    MedlinePlus

    ... further intracranial surgeries. Impaired sense of taste or smell : The sense of smell usually improves after the procedure because airflow is ... in their voice after sinus surgery. Impairment of smell or taste: (see above) Infection: The most common ...

  3. Heart valve surgery

    MedlinePlus

    ... techniques are used: Percutaneous surgery (through the skin) Robot-assisted surgery If your surgeon can repair your ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  4. Surgery for Bone Cancer

    MedlinePlus

    ... amputation. This is called limb-salvage or limb-sparing surgery . In going over treatment options, it is ... 2016 Treating Bone Cancer Surgery for Bone Cancer Radiation Therapy for Bone Cancer Chemotherapy for Bone Cancer Targeted ...

  5. Laparoscopic Spine Surgery

    MedlinePlus

    ... Opportunities Exhibit Opportunities Sponsorship Opportunities Log In Laparoscopic Spine Surgery Patient Information from SAGES Download PDF Find a SAGES Surgeon Laparoscopic Spine Surgery Your spine surgeon has determined that you ...

  6. What Is Refractive Surgery?

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  7. LASIK - Laser Eye Surgery

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  8. Breast Reduction Surgery

    MedlinePlus

    ... considering breast reduction surgery, consult a board-certified plastic surgeon. It's important to understand what breast reduction ... risk of complications from breast reduction surgery. Your plastic surgeon will likely: Evaluate your medical history and ...

  9. Smoking and surgery

    MedlinePlus

    Surgery - quitting smoking; Surgery - quitting tobacco; Wound healing - smoking ... encouraged. The nicotine will still interfere with the healing of your surgical wound and have the same effect on your general ...

  10. Cosmetic breast surgery - discharge

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000273.htm Cosmetic breast surgery - discharge To use the sharing features on this page, please enable JavaScript. You had cosmetic breast surgery to change the size or shape ...

  11. Shoulder surgery - discharge

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000179.htm Shoulder surgery - discharge To use the sharing features on this page, please enable JavaScript. You had shoulder surgery to repair the tissues inside or around ...

  12. Cosmetic ear surgery

    MedlinePlus

    Otoplasty; Ear pinning; Ear surgery - cosmetic; Ear reshaping; Pinnaplasty ... Cosmetic ear surgery may be done in the surgeon's office, an outpatient clinic, or a hospital. It can be performed under ...

  13. Hip fracture surgery

    MedlinePlus

    ... neck fracture repair; Trochanteric fracture repair; Hip pinning surgery; Osteoarthritis-hip ... You may receive general anesthesia before this surgery. This means ... spinal anesthesia. With this kind of anesthesia, medicine is ...

  14. Ear Plastic Surgery

    MedlinePlus

    ... Copyright © 2017 American Academy of Otolaryngology–Head and Neck Surgery. Reproduction or republication strictly prohibited without prior written ... Copyright 2017. American Academy of Otolaryngology — Head and Neck Surgery 1650 Diagonal Rd Alexandria, VA 22314 tel (703) ...

  15. Gastric bypass surgery - discharge

    MedlinePlus

    Bariatric surgery - gastric bypass - discharge; Roux-en-Y gastric bypass - discharge; Gastric bypass - Roux-en-Y - discharge; Obesity ... Gloy VL, Briel M, Bhatt DL, et al. Bariatric surgery versus non-surgical treatment for obesity: a systematic ...

  16. Abdominal wall surgery

    MedlinePlus

    ... the results of abdominoplasty. Many feel a new sense of self-confidence. Alternative Names Cosmetic surgery of the abdomen; Tummy tuck; Abdominoplasty Images Abdominoplasty - series Abdominal muscles References McGrath MH, Pomerantz J. Plastic surgery. In: Townsend ...

  17. Technology needs for corneal transplant surgery

    NASA Astrophysics Data System (ADS)

    Vaddavalli, Pravin K.; Yoo, Sonia H.

    2011-03-01

    Corneal transplant surgery has undergone numerous modifications over the years with improvements in technique, instrumentation and eye banking. The main goals of corneal transplantation are achieving excellent optical clarity with long-term graft survival. Penetrating, anterior and posterior lamellar surgery along with femtosecond laser technology have partially met these goals, but outcomes are often unpredictable and surgeon dependent. Technology to predictably separate stroma from Descemet's membrane, techniques to minimize endothelial cell loss, improvements in imaging technology and emerging techniques like laser welding that might replace suturing, eventually making corneal transplantation a refractively predictable procedure are on the wish list of the cornea surgeon.

  18. Spontaneous occlusion of cerebral arteriovenous malformation following partial embolization with Onyx.

    PubMed

    Nas, Omer Fatih; Ozturk, Kerem; Gokalp, Gokhan; Hakyemez, Bahattin

    2017-02-01

    Management options for brain arteriovenous malformations (AVMs) are surgery, radiosurgery, and endovascular embolization. The aim of partial embolization in endovascular treatment is to make total resection possible. However, increased risk of bleeding in partial embolization creates some controversies about treatment options. Spontaneous total occlusion of cerebral AVMs following partial obliteration with embolization agents is a rarely seen condition. We present a case with an AVM vanishing from right posterior cerebral artery which spontaneously occluded following partial embolization with Onyx liquid agent.

  19. Robotic liver surgery

    PubMed Central

    Leung, Universe

    2014-01-01

    Robotic surgery is an evolving technology that has been successfully applied to a number of surgical specialties, but its use in liver surgery has so far been limited. In this review article we discuss the challenges of minimally invasive liver surgery, the pros and cons of robotics, the evolution of medical robots, and the potentials in applying this technology to liver surgery. The current data in the literature are also presented. PMID:25392840

  20. Partial coalescence of soap bubbles

    NASA Astrophysics Data System (ADS)

    Harris, Daniel M.; Pucci, Giuseppe; Bush, John W. M.

    2015-11-01

    We present the results of an experimental investigation of the merger of a soap bubble with a planar soap film. When gently deposited onto a horizontal film, a bubble may interact with the underlying film in such a way as to decrease in size, leaving behind a smaller daughter bubble with approximately half the radius of its progenitor. The process repeats up to three times, with each partial coalescence event occurring over a time scale comparable to the inertial-capillary time. Our results are compared to the recent numerical simulations of Martin and Blanchette and to the coalescence cascade of droplets on a fluid bath.

  1. Pediatric heart surgery

    MedlinePlus

    Heart surgery - pediatric; Heart surgery for children; Acquired heart disease; Heart valve surgery - children ... There are many kinds of heart defects. Some are minor, and others are more serious. Defects can occur inside the heart or in the large blood vessels ...

  2. Infection after hand surgery.

    PubMed

    Eberlin, Kyle R; Ring, David

    2015-05-01

    Postoperative infections are uncommon after hand surgery. Infection can delay recovery and contribute to scarring and stiffness. Measures intended to reduce the risk of infection after hand surgery include hand washing, skin preparation, sterile technique, and prophylactic antibiotics. The role of prophylactic antibiotics for small, clean, elective hand surgery procedures lasting less than 2 hours is debated.

  3. Spine surgery - discharge

    MedlinePlus

    ... symptoms should get better in a few weeks. Recovery after laminectomy and fusion surgery is longer. You will not be able ... discharge; Anterior spinal fusion - discharge; Spine surgery - spinal fusion - discharge Images Spinal surgery -- cervical - series References Agrawal BM, Zeidman SM, Rhines L, ...

  4. Partial Torus Instability

    NASA Astrophysics Data System (ADS)

    Olmedo, Oscar; Zhang, J.

    2010-05-01

    Flux ropes are now generally accepted to be the magnetic configuration of Coronal Mass Ejections (CMEs), which may be formed prior or during solar eruptions. In this study, we model the flux rope as a current-carrying partial torus loop with its two footpoints anchored in the photosphere, and investigate its instability in the context of the torus instability (TI). Previous studies on TI have focused on the configuration of a circular torus and revealed the existence of a critical decay index. Our study reveals that the critical index is a function of the fractional number of the partial torus, defined by the ratio between the arc length of the partial torus above the photosphere and the circumference of a circular torus of equal radius. We refer to this finding the partial torus instability (PTI). It is found that a partial torus with a smaller fractional number has a smaller critical index, thus requiring a more gradually decreasing magnetic field to stabilize the flux rope. On the other hand, the partial torus with a larger fractional number has a larger critical index. In the limit of a circular torus when the fractional number approaches one, the critical index goes to a maximum value that depends on the distribution of the external magnetic field. We demonstrate that the partial torus instability helps us to understand the confinement, growth, and eventual eruption of a flux rope CME.

  5. Current status of robotic surgery in Japan

    PubMed Central

    2015-01-01

    The da Vinci S surgical system (Intuitive Surgical) was approved as a medical device in 2009 by the Japanese Ministry of Health, Labour and Welfare. Robotic surgery has since been used in gastrointestinal, thoracic, gynecological, and urological surgeries. In April 2012, robotic-assisted laparoscopic radical prostatectomy (RALP) was first approved for insurance coverage. Since then, RALP has been increasingly used, with more than 3,000 RALP procedures performed by March 2013. By July 2014, 183 institutions in Japan had installed the da Vinci surgical system. Other types of robotic surgeries are not widespread because they are not covered by public health insurance. Clinical trials using robotic partial nephrectomy and robotic gastrectomy for renal and gastric cancers, respectively, have recently begun as advanced medical treatments to evaluate health insurance coverage. These procedures must be evaluated for efficacy and safety before being covered by public health insurance. Other types of robotic surgery are being evaluated in clinical studies. There are several challenges in robotic surgery, including accreditation, training, efficacy, and cost. The largest issue is the cost-benefit balance. In this review, the current situation and a prospective view of robotic surgery in Japan are discussed. PMID:25763120

  6. Current status of robotic surgery in Japan.

    PubMed

    Nishimura, Kazuo

    2015-03-01

    The da Vinci S surgical system (Intuitive Surgical) was approved as a medical device in 2009 by the Japanese Ministry of Health, Labour and Welfare. Robotic surgery has since been used in gastrointestinal, thoracic, gynecological, and urological surgeries. In April 2012, robotic-assisted laparoscopic radical prostatectomy (RALP) was first approved for insurance coverage. Since then, RALP has been increasingly used, with more than 3,000 RALP procedures performed by March 2013. By July 2014, 183 institutions in Japan had installed the da Vinci surgical system. Other types of robotic surgeries are not widespread because they are not covered by public health insurance. Clinical trials using robotic partial nephrectomy and robotic gastrectomy for renal and gastric cancers, respectively, have recently begun as advanced medical treatments to evaluate health insurance coverage. These procedures must be evaluated for efficacy and safety before being covered by public health insurance. Other types of robotic surgery are being evaluated in clinical studies. There are several challenges in robotic surgery, including accreditation, training, efficacy, and cost. The largest issue is the cost-benefit balance. In this review, the current situation and a prospective view of robotic surgery in Japan are discussed.

  7. Partial knee replacement - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100225.htm Partial knee replacement - series—Normal anatomy To use the sharing ... A.M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited ...

  8. Twisted partially pure spinors

    NASA Astrophysics Data System (ADS)

    Herrera, Rafael; Tellez, Ivan

    2016-08-01

    Motivated by the relationship between orthogonal complex structures and pure spinors, we define twisted partially pure spinors in order to characterize spinorially subspaces of Euclidean space endowed with a complex structure.

  9. Partially coherent nonparaxial beams.

    PubMed

    Duan, Kailiang; Lü, Baida

    2004-04-15

    The concept of a partially coherent nonparaxial beam is proposed. A closed-form expression for the propagation of nonparaxial Gaussian Schell model (GSM) beams in free space is derived and applied to study the propagation properties of nonparaxial GSM beams. It is shown that for partially coherent nonparaxial beams a new parameter f(sigma) has to be introduced, which together with the parameter f, determines the beam nonparaxiality.

  10. Congenital medium sternal cleft with partial ectopia cordis repair.

    PubMed

    Sousa, Paulo Rego; Antunes, Sónia; Couto, Alexandra; Santos, Gonçalo Cassiano; Leal, Luis Gagp; Magalhães, Manuel Pedro

    2009-01-01

    Congenital sternal malformation is a rare anomaly often diagnosed as an asymptomatic condition at birth. The authors report a clinical case of a full-term female neonate with congenital sternal cleft and partial ectopia cordis. Successful surgical repair was accomplished at 6 days of age. When surgery is performed shortly after birth, the procedure is easier and better results are achieved.

  11. PARTIAL TORUS INSTABILITY

    SciTech Connect

    Olmedo, Oscar; Zhang Jie

    2010-07-20

    Flux ropes are now generally accepted to be the magnetic configuration of coronal mass ejections (CMEs), which may be formed prior to or during solar eruptions. In this study, we model the flux rope as a current-carrying partial torus loop with its two footpoints anchored in the photosphere, and investigate its stability in the context of the torus instability (TI). Previous studies on TI have focused on the configuration of a circular torus and revealed the existence of a critical decay index of the overlying constraining magnetic field. Our study reveals that the critical index is a function of the fractional number of the partial torus, defined by the ratio between the arc length of the partial torus above the photosphere and the circumference of a circular torus of equal radius. We refer to this finding as the partial torus instability (PTI). It is found that a partial torus with a smaller fractional number has a smaller critical index, thus requiring a more gradually decreasing magnetic field to stabilize the flux rope. On the other hand, a partial torus with a larger fractional number has a larger critical index. In the limit of a circular torus when the fractional number approaches 1, the critical index goes to a maximum value. We demonstrate that the PTI helps us to understand the confinement, growth, and eventual eruption of a flux-rope CME.

  12. Partial Torus Instability

    NASA Astrophysics Data System (ADS)

    Olmedo, Oscar; Zhang, Jie

    2010-07-01

    Flux ropes are now generally accepted to be the magnetic configuration of coronal mass ejections (CMEs), which may be formed prior to or during solar eruptions. In this study, we model the flux rope as a current-carrying partial torus loop with its two footpoints anchored in the photosphere, and investigate its stability in the context of the torus instability (TI). Previous studies on TI have focused on the configuration of a circular torus and revealed the existence of a critical decay index of the overlying constraining magnetic field. Our study reveals that the critical index is a function of the fractional number of the partial torus, defined by the ratio between the arc length of the partial torus above the photosphere and the circumference of a circular torus of equal radius. We refer to this finding as the partial torus instability (PTI). It is found that a partial torus with a smaller fractional number has a smaller critical index, thus requiring a more gradually decreasing magnetic field to stabilize the flux rope. On the other hand, a partial torus with a larger fractional number has a larger critical index. In the limit of a circular torus when the fractional number approaches 1, the critical index goes to a maximum value. We demonstrate that the PTI helps us to understand the confinement, growth, and eventual eruption of a flux-rope CME.

  13. Tree reconstruction from partial orders

    SciTech Connect

    Kannan, S.K. ); Warnow, T.J. )

    1993-01-01

    The problem of constructing trees given a matrix of interleaf distances is motivated by applications in computational evolutionary biology and linguistics. The general problem is to find an edge-weighted tree which most closely approximates the distance matrix. Although the construction problem is easy when the tree exactly fits the distance matrix, optimization problems under all popular criteria are either known or conjectured to be NP-complete. In this paper we consider the related problem where we are given a partial order on the pairwise distances, and wish to construct (if possible) an edge-weighted tree realizing the partial order. In particular we are interested in partial orders which arise from experiments on triples of species, which determine either a linear ordering of the three pairwise distances (called Total Order Model or TOM experiments) or only the pair(s) of minimum distance apart (called Partial Order Model or POM experiments). The POM and TOM experimental model is inspired by the model proposed by Kannan, Lawler, and Warnow for constructing trees from experiments which determine the rooted topology for any triple of species. We examine issues of construction of trees and consistency of TOM and POM experiments, where the trees may either be weighted or unweighted. Using these experiments to construct unweighted trees without nodes of degree two is motivated by a similar problem studied by Winkler, called the Discrete Metric Realization problem, which he showed to be strongly NP-hard. We have the following results: Determining consistency of a set of TOM or POM experiments is NP-Complete whether the tree is weighted or constrained to be unweighted and without degree two nodes. We can construct unweighted trees without degree two nodes from TOM experiments in optimal O(n[sup 3]) time and from POM experiments in O(n[sup 4]) time.

  14. Tree reconstruction from partial orders

    SciTech Connect

    Kannan, S.K.; Warnow, T.J.

    1993-03-01

    The problem of constructing trees given a matrix of interleaf distances is motivated by applications in computational evolutionary biology and linguistics. The general problem is to find an edge-weighted tree which most closely approximates the distance matrix. Although the construction problem is easy when the tree exactly fits the distance matrix, optimization problems under all popular criteria are either known or conjectured to be NP-complete. In this paper we consider the related problem where we are given a partial order on the pairwise distances, and wish to construct (if possible) an edge-weighted tree realizing the partial order. In particular we are interested in partial orders which arise from experiments on triples of species, which determine either a linear ordering of the three pairwise distances (called Total Order Model or TOM experiments) or only the pair(s) of minimum distance apart (called Partial Order Model or POM experiments). The POM and TOM experimental model is inspired by the model proposed by Kannan, Lawler, and Warnow for constructing trees from experiments which determine the rooted topology for any triple of species. We examine issues of construction of trees and consistency of TOM and POM experiments, where the trees may either be weighted or unweighted. Using these experiments to construct unweighted trees without nodes of degree two is motivated by a similar problem studied by Winkler, called the Discrete Metric Realization problem, which he showed to be strongly NP-hard. We have the following results: Determining consistency of a set of TOM or POM experiments is NP-Complete whether the tree is weighted or constrained to be unweighted and without degree two nodes. We can construct unweighted trees without degree two nodes from TOM experiments in optimal O(n{sup 3}) time and from POM experiments in O(n{sup 4}) time.

  15. Ultrasound-Assisted Endoscopic Partial Plantar Fascia Release

    PubMed Central

    Ohuchi, Hiroshi; Ichikawa, Ken; Shinga, Kotaro; Hattori, Soichi; Yamada, Shin; Takahashi, Kazuhisa

    2013-01-01

    Various surgical treatment procedures for plantar fasciitis, such as open surgery, percutaneous release, and endoscopic surgery, exist. Skin trouble, nerve disturbance, infection, and persistent pain associated with prolonged recovery time are complications of open surgery. Endoscopic partial plantar fascia release offers the surgeon clear visualization of the anatomy at the surgical site. However, the primary medial portal and portal tract used for this technique have been shown to be in close proximity to the posterior tibial nerves and their branches, and there is always the risk of nerve damage by introducing the endoscope deep to the plantar fascia. By performing endoscopic partial plantar fascia release under ultrasound assistance, we could dynamically visualize the direction of the endoscope and instrument introduction, thus preventing nerve damage from inadvertent insertion deep to the fascia. Full-thickness release of the plantar fascia at the ideal position could also be confirmed under ultrasound imaging. We discuss the technique for this new procedure. PMID:24265989

  16. Metabolic surgery: quo vadis?

    PubMed

    Ramos-Leví, Ana M; Rubio Herrera, Miguel A

    2014-01-01

    The impact of bariatric surgery beyond its effect on weight loss has entailed a change in the way of regarding it. The term metabolic surgery has become more popular to designate those interventions that aim at resolving diseases that have been traditionally considered as of exclusive medical management, such as type 2 diabetes mellitus (T2D). Recommendations for metabolic surgery have been largely addressed and discussed in worldwide meetings, but no definitive consensus has been reached yet. Rates of diabetes remission after metabolic surgery have been one of the most debated hot topics, with heterogeneity being a current concern. This review aims to identify and clarify controversies regarding metabolic surgery, by focusing on a critical analysis of T2D remission rates achieved with different bariatric procedures, and using different criteria for its definition. Indications for metabolic surgery for patients with T2D who are not morbidly obese are also discussed.

  17. Oxygen partial pressure sensor

    DOEpatents

    Dees, D.W.

    1994-09-06

    A method for detecting oxygen partial pressure and an oxygen partial pressure sensor are provided. The method for measuring oxygen partial pressure includes contacting oxygen to a solid oxide electrolyte and measuring the subsequent change in electrical conductivity of the solid oxide electrolyte. A solid oxide electrolyte is utilized that contacts both a porous electrode and a nonporous electrode. The electrical conductivity of the solid oxide electrolyte is affected when oxygen from an exhaust stream permeates through the porous electrode to establish an equilibrium of oxygen anions in the electrolyte, thereby displacing electrons throughout the electrolyte to form an electron gradient. By adapting the two electrodes to sense a voltage potential between them, the change in electrolyte conductivity due to oxygen presence can be measured. 1 fig.

  18. Oxygen partial pressure sensor

    DOEpatents

    Dees, Dennis W.

    1994-01-01

    A method for detecting oxygen partial pressure and an oxygen partial pressure sensor are provided. The method for measuring oxygen partial pressure includes contacting oxygen to a solid oxide electrolyte and measuring the subsequent change in electrical conductivity of the solid oxide electrolyte. A solid oxide electrolyte is utilized that contacts both a porous electrode and a nonporous electrode. The electrical conductivity of the solid oxide electrolyte is affected when oxygen from an exhaust stream permeates through the porous electrode to establish an equilibrium of oxygen anions in the electrolyte, thereby displacing electrons throughout the electrolyte to form an electron gradient. By adapting the two electrodes to sense a voltage potential between them, the change in electrolyte conductivity due to oxygen presence can be measured.

  19. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    1999-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  20. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, S.; Kumar, R.; Krumpelt, M.

    1999-08-17

    A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

  1. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, S.; Kumar, R.; Krumpelt, M.

    1999-08-24

    A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

  2. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    2001-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  3. Fundamentals of bipolar high-frequency surgery.

    PubMed

    Reidenbach, H D

    1993-04-01

    In endoscopic surgery a very precise surgical dissection technique and an efficient hemostasis are of decisive importance. The bipolar technique may be regarded as a method which satisfies both requirements, especially regarding a high safety standard in application. In this context the biophysical and technical fundamentals of this method, which have been known in principle for a long time, are described with regard to the special demands of a newly developed field of modern surgery. After classification of this method into a general and a quasi-bipolar mode, various technological solutions of specific bipolar probes, in a strict and in a generalized sense, are characterized in terms of indication. Experimental results obtained with different bipolar instruments and probes are given. The application of modern microprocessor-controlled high-frequency surgery equipment and, wherever necessary, the integration of additional ancillary technology into the specialized bipolar instruments may result in most useful and efficient tools of a key technology in endoscopic surgery.

  4. Periscopic Spine Surgery

    DTIC Science & Technology

    2005-01-01

    AD Award Number: W81XWH-04-1-0078 TITLE: Periscopic Spine Surgery PRINCIPAL INVESTIGATOR: Kevin R. Cleary, Ph.D. CONTRACTING ORGANIZATION: Georgetown...2005 Annual (22 Dec 2003 - 21 Dec 2004) 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Periscopic Spine Surgery W81XWH-04-1-0078 6. AUTHOR(S) Kevin R. Cleary... Surgery -specific image acquisition, processing, and display are needed. The two- dimensional (2D) static images typically used today are not sufficient

  5. Partially strong WW scattering

    SciTech Connect

    Cheung Kingman; Chiang Chengwei; Yuan Tzuchiang

    2008-09-01

    What if only a light Higgs boson is discovered at the CERN LHC? Conventional wisdom tells us that the scattering of longitudinal weak gauge bosons would not grow strong at high energies. However, this is generally not true. In some composite models or general two-Higgs-doublet models, the presence of a light Higgs boson does not guarantee complete unitarization of the WW scattering. After partial unitarization by the light Higgs boson, the WW scattering becomes strongly interacting until it hits one or more heavier Higgs bosons or other strong dynamics. We analyze how LHC experiments can reveal this interesting possibility of partially strong WW scattering.

  6. Hyperoxaluria and Bariatric Surgery

    NASA Astrophysics Data System (ADS)

    Asplin, John R.

    2007-04-01

    Bariatric surgery as a means to treat obesity is becoming increasingly common in the United States. An early form of bariatric surgery, the jejunoileal bypass, had to be abandoned in 1980 due to numerous complications, including hyperoxaluria and kidney stones. Current bariatric procedures have not been systematically evaluated to determine if they cause hyperoxaluria. Presented here are data showing that hyperoxaluria is the major metabolic abnormality in patients with bariatric surgery who form kidney stones. Further studies are needed to assess the prevalence of hyperoxaluria in all patients with bariatric surgery.

  7. Surgery: a risky business.

    PubMed

    Vats, Amit; Nagpal, Kamal; Moorthy, Krishna

    2009-10-01

    The advancement of surgical technology has made surgery an increasingly suitable management option for an increasing number of medical conditions. Yet there is also a growing concern about the number of patients coming to harm as a result of surgery. Studies show that this harm can be prevented by better teamwork and communication in operating theatres. This article discusses the extent of adverse events in surgery and how effective teamwork and communication can improve patient safety. It also highlights the role checklists and briefing in improving teamwork and reducing human error in surgery.

  8. Complications of Strabismus Surgery

    PubMed Central

    Olitsky, Scott E.; Coats, David K.

    2015-01-01

    All surgeries carry risks of complications, and there is no way to avoid ever having a complication. Strabismus surgery is no different in this regard. There are methods to reduce the risk of a complication during or after surgery, and these steps should always be taken. When a complication occurs, it is important to first recognize it and then manage it appropriately to allow for the best outcome possible. This article will discuss some of the more common and/or most devastating complications that can occur during or after strabismus surgery as well as thoughts on how to avoid them and manage them should they happen. PMID:26180463

  9. Lung surgery - discharge

    MedlinePlus

    Thoracotomy - discharge; Lung tissue removal - discharge; Pneumonectomy - discharge; Lobectomy - discharge; Lung biopsy - discharge; Thoracoscopy - discharge; Video-assisted thoracoscopic surgery - discharge; VATS - ...

  10. Simple technique for generating the partially coherent and partially polarized electromagnetic source

    NASA Astrophysics Data System (ADS)

    Ostrovsky, A. S.; Rodríguez, G.; Meneses, C.; Olvera, M. Á.; Juárez, E.

    2011-01-01

    The technique for generating the partially coherent and partially polarized source starting from the completely coherent and completely polarized laser source is proposed and analyzed. This technique differs from the known ones by the simplicity of its physical realization. An original technique for measuring the cross-spectral density matrix is employed. Experimental results of the characterization the coherence and polarization properties of the generated source are shown.

  11. Value of Robotically Assisted Surgery for Mitral Valve Disease

    PubMed Central

    Mihaljevic, Tomislav; Koprivanac, Marijan; Kelava, Marta; Goodman, Avi; Jarrett, Craig; Williams, Sarah J.; Gillinov, A. Marc; Bajwa, Gurjyot; Mick, Stephanie L.; Bonatti, Johannes; Blackstone, Eugene H.

    2014-01-01

    Importance The value of robotically assisted surgery for mitral valve disease is questioned because the high cost of care associated with robotic technology may outweigh its clinical benefits. Objective To investigate conditions under which benefits of robotic surgery mitigate high technology costs. Design Clinical cohort study comparing costs of robotic vs. three contemporaneous conventional surgical approaches for degenerative mitral disease. Surgery was performed from 2006–2011, and comparisons were based on intent-to-treat, with propensity-matching used to reduce selection bias. Setting Large multi-specialty academic medical center. Participants 1,290 patients aged 57±11 years, 27% women, underwent mitral repair for regurgitation from posterior leaflet prolapse. Robotic surgery was used in 473, complete sternotomy in 227, partial sternotomy in 349, and anterolateral thoracotomy in 241. Three propensity-matched groups were formed based on demographics, symptoms, cardiac and noncardiac comorbidities, valve pathophysiology, and echocardiographic measurements: robotic vs. sternotomy (n=198 pairs) vs. partial sternotomy (n=293 pairs) vs. thoracotomy (n=224 pairs). Interventions Mitral valve repair. Main Outcome Measures Cost of care, expressed as robotic capital investment, maintenance, and direct technical hospital cost, and benefit of care, based on differences in recovery time. Results Median cost of care for robotically assisted surgery exceeded the cost of alternative approaches by 27% (−5%, 68%), 32% (−6%, 70%), and 21% (−2%, 54%) (median [15th, 85th percentiles]) for complete sternotomy, partial sternotomy, and anterolateral thoracotomy, respectively. Higher operative costs were partially offset by lower postoperative costs and earlier return to work: median 35 days for robotic surgery, 49 for complete sternotomy, 56 for partial sternotomy, and 42 for anterolateral thoracotomy. Resulting net differences in cost of robotic surgery vs. the three

  12. Secondary surgery in paediatric facial paralysis reanimation.

    PubMed

    Terzis, Julia K; Olivares, Fatima S

    2010-11-01

    Ninety-two children, the entire series of paediatric facial reanimation by a single surgeon over thirty years, are presented. The objective is to analyse the incidence and value of secondary revisions for functional and aesthetic refinements following the two main stages of reanimation. The reconstructive strategy varied according to the denervation time, the aetiology, and whether the paralysis was uni- or bilateral, complete or partial. Irrespective of these variables, 89% of the patients required secondary surgery. Post-operative videos were available in seventy-two cases. Four independent observers graded patients' videos using a scale from poor to excellent. The effect of diverse secondary procedures was measured computing a mean-percent-gain score. Statistical differences between treatment groups means were tested by the t-test and one-way ANOVA. Two-thirds of the corrective and ancillary techniques utilized granted significantly higher mean-scores post-secondary surgery. A comparison of pre- and post-operative data found valuable improvements in all three facial zones after secondary surgery. In conclusion, inherent to dynamic procedures is the need for secondary revisions. Secondary surgery builds in the potential of reanimation surgery, effectively augmenting functional faculties and aesthesis.

  13. Partial polarizer filter

    NASA Technical Reports Server (NTRS)

    Title, A. M. (Inventor)

    1978-01-01

    A birefringent filter module comprises, in seriatum. (1) an entrance polarizer, (2) a first birefringent crystal responsive to optical energy exiting the entrance polarizer, (3) a partial polarizer responsive to optical energy exiting the first polarizer, (4) a second birefringent crystal responsive to optical energy exiting the partial polarizer, and (5) an exit polarizer. The first and second birefringent crystals have fast axes disposed + or -45 deg from the high transmitivity direction of the partial polarizer. Preferably, the second crystal has a length 1/2 that of the first crystal and the high transmitivity direction of the partial polarizer is nine times as great as the low transmitivity direction. To provide tuning, the polarizations of the energy entering the first crystal and leaving the second crystal are varied by either rotating the entrance and exit polarizers, or by sandwiching the entrance and exit polarizers between pairs of half wave plates that are rotated relative to the polarizers. A plurality of the filter modules may be cascaded.

  14. Dilemmas of partial cooperation.

    PubMed

    Stark, Hans-Ulrich

    2010-08-01

    Related to the often applied cooperation models of social dilemmas, we deal with scenarios in which defection dominates cooperation, but an intermediate fraction of cooperators, that is, "partial cooperation," would maximize the overall performance of a group of individuals. Of course, such a solution comes at the expense of cooperators that do not profit from the overall maximum. However, because there are mechanisms accounting for mutual benefits after repeated interactions or through evolutionary mechanisms, such situations can constitute "dilemmas" of partial cooperation. Among the 12 ordinally distinct, symmetrical 2 x 2 games, three (barely considered) variants are correspondents of such dilemmas. Whereas some previous studies investigated particular instances of such games, we here provide the unifying framework and concisely relate it to the broad literature on cooperation in social dilemmas. Complementing our argumentation, we study the evolution of partial cooperation by deriving the respective conditions under which coexistence of cooperators and defectors, that is, partial cooperation, can be a stable outcome of evolutionary dynamics in these scenarios. Finally, we discuss the relevance of such models for research on the large biodiversity and variation in cooperative efforts both in biological and social systems.

  15. Experimental determination of C, F, and H partitioning between mantle minerals and carbonated basalt, CO2/Ba and CO2/Nb systematics of partial melting, and the CO2 contents of basaltic source regions

    NASA Astrophysics Data System (ADS)

    Rosenthal, A.; Hauri, E. H.; Hirschmann, M. M.

    2015-02-01

    To determine partitioning of C between upper mantle silicate minerals and basaltic melts, we executed 26 experiments between 0.8 and 3 GPa and 1250-1500 °C which yielded 37 mineral/glass pairs suitable for C analysis by secondary ion mass spectrometry (SIMS). To enhance detection limits, experiments were conducted with 13C-enriched bulk compositions. Independent measurements of 13C and 12C in coexisting phases produced two C partition coefficients for each mineral pair and allowed assessment of the approach to equilibrium during each experiment. Concentrations of C in olivine (ol), orthopyroxene (opx), clinopyroxene (cpx) and garnet (gt) range from 0.2 to 3.5 ppm, and resulting C partition coefficients for ol/melt, opx/melt, cpx/melt and gt/melt are, respectively, 0.0007 ± 0.0004 (n = 2), 0.0003 ± 0.0002 (n = 45), 0.0005 ± 0.0004 (n = 17) and 0.0001 ± 0.00007 (n = 5). The effective partition coefficient of C during partial melting of peridotite is 0.00055 ± 0.00025, and therefore C is significantly more incompatible than Nb, slightly more compatible than Ba, and, among refractory trace elements, most similar in behavior to U or Th. Experiments also yielded partition coefficients for F and H between minerals and melts. Combining new and previous values of DFmineral/melt yields bulk DFperidotite/melt = 0.011 ± 0.002, which suggests that F behaves similarly to La during partial melting of peridotite. Values of DHpyx/melt correlate with tetrahedral Al along a trend consistent with previously published determinations. Small-degree partial melting of the mantle results in considerable CO2/Nb fractionation, which is likely the cause of high CO2/Nb evident in some Nb-rich oceanic basalts. CO2/Ba is much less easily fractionated, with incompatible-element-enriched partial melts having lower CO2/Ba than less enriched basalts. Comparison of calculated behavior of CO2, Nb, and Ba to systematics of oceanic basalts suggests that depleted (DMM-like) sources have 75 ± 25

  16. An Ultrasonic Clamp for Bloodless Partial Nephrectomy

    NASA Astrophysics Data System (ADS)

    Lafon, Cyril; Bouchoux, Guillaume; Murat, François Joseph; Birer, Alain; Theillère, Yves; Chapelon, Jean Yves; Cathignol, Dominique

    2007-05-01

    Maximum conservation of the kidney is preferable through partial nephrectomy for patients at risk of disease recurrence of renal cancers. Haemostatic tools are needed in order to achieve bloodless surgery and reduce post surgery morbidity. Two piezo-ceramic transducers operating at a frequency of 4 MHz were mounted on each arm of a clamp. When used for coagulation purposes, two transducers situated on opposite arms of the clamp were driven simultaneously. Heat delivery was optimized as each transducers mirrored back to targeted tissues the wave generated by the opposite transducer. Real-time treatment monitoring with an echo-based technique was also envisaged with this clamp. Therapy was periodically interrupted so one transducer could generate a pulse. The echo returning from the opposite transducer was treated. Coagulation necroses were obtained in vitro on substantial thicknesses (23-38mm) of pig liver over exposure durations ranging from 30s to 130s, and with acoustic intensities of less than 15W/cm2 per transducer. Both kidneys of two pigs were treated in vivo with the clamp (14.5W/cm2 for 90s), and the partial nephrectomies performed proved to be bloodless. In vitro and in vivo, wide transfixing lesions corresponded to an echo energy decrease superior to -10dB and parabolic form of the time of flight versus treatment time. In conclusion, this ultrasound clamp has proven to be an excellent mean for achieving monitored haemostasis in kidney.

  17. Minimally invasive aortic valve surgery

    PubMed Central

    Castrovinci, Sebastiano; Emmanuel, Sam; Moscarelli, Marco; Murana, Giacomo; Caccamo, Giuseppa; Bertolino, Emanuela Clara; Nasso, Giuseppe; Speziale, Giuseppe; Fattouch, Khalil

    2016-01-01

    Aortic valve disease is a prevalent disorder that affects approximately 2% of the general adult population. Surgical aortic valve replacement is the gold standard treatment for symptomatic patients. This treatment has demonstrably proven to be both safe and effective. Over the last few decades, in an attempt to reduce surgical trauma, different minimally invasive approaches for aortic valve replacement have been developed and are now being increasingly utilized. A narrative review of the literature was carried out to describe the surgical techniques for minimally invasive aortic valve surgery and report the results from different experienced centers. Minimally invasive aortic valve replacement is associated with low perioperative morbidity, mortality and a low conversion rate to full sternotomy. Long-term survival appears to be at least comparable to that reported for conventional full sternotomy. Minimally invasive aortic valve surgery, either with a partial upper sternotomy or a right anterior minithoracotomy provides early- and long-term benefits. Given these benefits, it may be considered the standard of care for isolated aortic valve disease. PMID:27582764

  18. Evaluation of Migraine Surgery Outcomes through Social Media

    PubMed Central

    Egan, Katie G.; Israel, Jacqueline S.; Ghasemzadeh, Rezvaneh

    2016-01-01

    Background: Social media have been used to study many aspects of health and human behavior. Although social media present a unique opportunity to obtain unsolicited patient-reported outcomes, its use has been limited in plastic and reconstructive surgical procedures, including migraine nerve surgery. The goal of this study was to utilize the most popular social media site, Facebook, to evaluate patients’ experience with migraine surgery. Methods: Six months of data regarding nerve surgery, nerve stimulators, and radiofrequency nerve ablation were collected from posts and comments written by members of 2 Facebook groups. Outcomes were classified by degree of resolution of symptoms. Results: A total of 639 posts related to migraine surgery. Of 304 posts commenting on postoperative success of nerve surgery, 16% reported elimination of headaches and 65% significant improvement (81% with complete or significant improvement), 5% partial improvement, 11% no change, and 3% worsening symptoms. Nerve surgery had a higher success rate than nerve stimulators and radiofrequency ablation. Nerve surgery was recommended by 90% of users. Conclusions: The 81% rate of complete or significant improvement of symptoms in this study is close to the 79% to 84% shown in current literature. Similar to the findings of a recent systematic review, surgery is more efficacious compared with nerve stimulators and ablation. This study adds to evidence favoring migraine surgery by removing evaluator bias and demonstrates that surgical outcomes and satisfaction data may be obtained from social media. PMID:27826478

  19. Robot-assisted laparoscopic partial adrenalectomy: a case report and review of the literature.

    PubMed

    Yates, Jennifer; Uberoi, Jayant; Munver, Ravi

    2010-09-01

    Adrenal-sparing surgery has recently been reported in the literature on minimally-invasive surgery. Originally described as a conventional laparoscopic procedure, encouraging outcomes in terms of preservation of adrenal function have been reported. Since the introduction of robotic surgery, surgeons have utilized robotic assistance for adrenal surgery and have recently described adrenal-sparing surgery using this platform. Certain patients that present with adrenal masses may benefit from minimally-invasive partial adrenalectomy, including those with a solitary adrenal gland, bilateral adrenal masses, and hereditary disease predisposing them to multiple adrenal masses. Patients without these conditions may also benefit from adrenal-sparing surgery in order to preserve normal adrenal function. We present the case of a patient with a 1.5-cm adrenal mass who elected to undergo adrenal-sparing surgery. The technique of transperitoneal laparoscopic partial adrenalectomy utilizing the da Vinci™ Surgical System is described. We also review the literature on minimally-invasive partial adrenalectomy in which robotic-assistance was utilized. In conclusion, while robot-assisted laparoscopic partial adrenalectomy remains in its infancy, it can be performed safely and with satisfactory surgical and functional outcomes.

  20. [Robotic surgery in gynecology].

    PubMed

    Csorba, Roland

    2012-06-24

    Minimally invasive surgery has revolutionized gynecological interventions over the past 30 years. The introduction of the da Vinci robotic surgery in 2005 has resulted in large changes in surgical management. The robotic platform allows less experienced laparoscopic surgeons to perform more complex procedures. It can be utilized mainly in general gynecology and reproductive gynecology. The robot is being increasingly used for procedures such as hysterectomy, myomectomy, adnexal surgery, and tubal anastomosis. In urogynecology, the robot is being utilized for sacrocolopexy as well. In the field of gynecologic oncology, the robot is being increasingly used for hysterectomy and lymphadenectomy in oncologic diseases. Despite the rapid and widespread adaption of robotic surgery in gynecology, there are no randomized trials comparing its efficacy and safety to other traditional surgical approaches. This article presents the development, technical aspects and indications of robotic surgery in gynecology, based on the previously published reviews. Robotic surgery can be highly advantageous with the right amount of training, along with appropriate patient selection. Patients will have less blood loss, less post-operative pain, faster recovery, and fewer complications compared to open surgery and laparoscopy. However, until larger randomized control trials are completed which report long-term outcomes, robotic surgery cannot be stated to have priority over other surgical methods.

  1. Penile enlargement surgery.

    PubMed

    Alter, G J

    1998-06-01

    Aesthetic surgery to improve the appearance of the penis, scrotum, and pubic region has successfully evolved. Penile lengthening is performed by releasing the suspensory ligament of the penis followed by use of penile weights. Girth is increased by wrapping a dermal-fat graft around the penile circumference. The choice of surgery is determined by the patient's anatomy and desires.

  2. Advances in fetal surgery

    PubMed Central

    Pedreira, Denise Araujo Lapa

    2016-01-01

    ABSTRACT This paper discusses the main advances in fetal surgical therapy aiming to inform health care professionals about the state-of-the-art techniques and future challenges in this field. We discuss the necessary steps of technical evolution from the initial open fetal surgery approach until the development of minimally invasive techniques of fetal endoscopic surgery (fetoscopy). PMID:27074241

  3. Partial coalescence of soap bubbles

    NASA Astrophysics Data System (ADS)

    Pucci, G.; Harris, D. M.; Bush, J. W. M.

    2015-06-01

    We present the results of an experimental investigation of the merger of a soap bubble with a planar soap film. When gently deposited onto a horizontal film, a bubble may interact with the underlying film in such a way as to decrease in size, leaving behind a smaller daughter bubble with approximately half the radius of its progenitor. The process repeats up to three times, with each partial coalescence event occurring over a time scale comparable to the inertial-capillary time. Our results are compared to the recent numerical simulations of Martin and Blanchette ["Simulations of surfactant effects on the dynamics of coalescing drops and bubbles," Phys. Fluids 27, 012103 (2015)] and to the coalescence cascade of droplets on a fluid bath.

  4. Partial Return Yoke for MICE

    SciTech Connect

    Witte H.; Plate, S

    2013-05-03

    The international Muon Ionization Cooling Experiment (MICE) is a large scale experiment which is presently assembled at the Rutherford Appleton Laboratory in Didcot, UK. The purpose of MICE is to demonstrate the concept of ionization cooling experimentally. Ionization cooling is an important accelerator concept which will be essential for future HEP experiments such as a potential Muon Collider or a Neutrino Factory. The MICE experiment will house up to 18 superconducting solenoids, all of which produce a substantial amount of magnetic flux. Recently it was realized that this magnetic flux leads to a considerable stray magnetic field in the MICE hall. This is a concern as technical equipment in the MICE hall may may be compromised by this. In July 2012 a concept called partial return yoke was presented to the MICE community, which reduces the stray field in the MICE hall to a safe level. This report summarizes the general concept, engineering considerations and the expected shielding performance.

  5. Orbital endoscopic surgery.

    PubMed

    Prabhakaran, Venkatesh C; Selva, Dinesh

    2008-01-01

    Minimally invasive "keyhole" surgery performed using endoscopic visualization is increasing in popularity and is being used by almost all surgical subspecialties. Within ophthalmology, however, endoscopic surgery is not commonly performed and there is little literature on the use of the endoscope in orbital surgery. Transorbital use of the endoscope can greatly aid in visualizing orbital roof lesions and minimizing the need for bone removal. The endoscope is also useful during decompression procedures and as a teaching aid to train orbital surgeons. In this article, we review the history of endoscopic orbital surgery and provide an overview of the technique and describe situations where the endoscope can act as a useful adjunct to orbital surgery.

  6. ROBOTIC SURGERY: BIOETHICAL ASPECTS

    PubMed Central

    SIQUEIRA-BATISTA, Rodrigo; SOUZA, Camila Ribeiro; MAIA, Polyana Mendes; SIQUEIRA, Sávio Lana

    2016-01-01

    ABSTRACT Introduction: The use of robots in surgery has been increasingly common today, allowing the emergence of numerous bioethical issues in this area. Objective: To present review of the ethical aspects of robot use in surgery. Method: Search in Pubmed, SciELO and Lilacs crossing the headings "bioethics", "surgery", "ethics", "laparoscopy" and "robotic". Results: Of the citations obtained, were selected 17 articles, which were used for the preparation of the article. It contains brief presentation on robotics, its inclusion in health and bioethical aspects, and the use of robots in surgery. Conclusion: Robotic surgery is a reality today in many hospitals, which makes essential bioethical reflection on the relationship between health professionals, automata and patients. PMID:28076489

  7. [Aesthetic surgery and history].

    PubMed

    Glicenstein, J

    2003-10-01

    The history of aesthetic surgery is linked to that of the 20th century. The first operations allowed by the progress of anesthesia and asepsis are the correction of "prominent ears" by Ely then rhinoplasty with endonasal incision by Roe. Considered by some as a precursor and a quack by others, C.C. Miller was the first surgeon to specialize and write books on the subject. Before world war I, aesthetic surgery was seldom practiced and publications were few. The war was at the origin of several units of maxillo-facial surgery created for the huge number of casualties with face trauma due to trench warfare. Many of those who will become great names in plastic surgery operated in these units: Blair, Davis, Léon Dufourmentel, Virenque, Morestin and Gillies. After the war, American surgeons were regrouped in scientific societies. Plastic surgery was privileged and aesthetic surgery was lifted for "quacks". In France, several surgeons such as Suzanne Noël, Passot, Bourguet, Dartigues showed an important creativity and described several techniques that inspired recent ones. The Dujarier case discredited French aesthetic surgery but did not stop the creation of the first French Society of Plastic Surgery in 1930. World war II led to new orientations. In England, the East Grinstead center with Gillies and McIndoe during and after the war was at the origin of many vocations. After the war, many national and international societies of plastic surgery started to appear. The French Society of Plastic Surgery was born in 1952.

  8. Clinical outcome of partial ethmoidectomy for chronic rhinosinusitis.

    PubMed

    Iro, Heinrich; Mayr, Susanne; Schick, Bernhard; Mrakovcic, Gracia; Wigand, Malte Erik

    2006-06-01

    Since its introduction endoscopic sinus surgery (ESS) for the treatment of chronic rhinosinusitis (CRS) has been focused on the management of the ethmoids, differentiating between partial and total ethmoidectomy. The classification of the underlying process of ethmoiditis and the selection of the adequate surgical procedure are still open questions. The aim of this investigation was to evaluate a minimally invasive ESS procedure. We present a retrospective analysis of 112 cases of bilateral circumscribed ethmoiditis after partial ethmoidectomy performed by a single surgeon investigated by questionnaires and endoscopic follow-up. A comparison of symptoms and the subjective judgment of the patients before and after surgery showed that postoperative subjective scores of nasal obstruction and rhinorrhea improved in up to 90%, with no distinct differences between primary intervention (n=98) and revision (n=14). Ninety percent of all patients considered surgery successful. Signs of active rhinosinusitis were found in less then 20% of patients after partial ethmoidectomy. This demonstrates that partial ethmoidectomy is an effective treatment for CRS affecting only part of the ethmoid.

  9. Self-steering partially coherent beams

    NASA Astrophysics Data System (ADS)

    Chen, Yahong; Ponomarenko, Sergey A.; Cai, Yangjian

    2017-01-01

    We introduce a class of shape-invariant partially coherent beams with a moving guiding center which we term self-steering partially coherent beams. The guiding center of each such beam evolves along a straight line trajectory which can be engineered to make any angle with the x-axis. We show that the straight line trajectory of the guiding center is the only option in free space due to the linear momentum conservation. We experimentally generate a particular subclass of new beams, self-steering Gaussian Schell beams and argue that they can find applications for mobile target tracing and trapped micro- and/or nanoparticle transport.

  10. Self-steering partially coherent beams

    PubMed Central

    Chen, Yahong; Ponomarenko, Sergey A.; Cai, Yangjian

    2017-01-01

    We introduce a class of shape-invariant partially coherent beams with a moving guiding center which we term self-steering partially coherent beams. The guiding center of each such beam evolves along a straight line trajectory which can be engineered to make any angle with the x-axis. We show that the straight line trajectory of the guiding center is the only option in free space due to the linear momentum conservation. We experimentally generate a particular subclass of new beams, self-steering Gaussian Schell beams and argue that they can find applications for mobile target tracing and trapped micro- and/or nanoparticle transport. PMID:28051164

  11. Proximity to Intrinsic Depolarizing Resonances with a Partial Siberian Snake

    NASA Astrophysics Data System (ADS)

    Crandell, D. A.; Alexeeva, L. V.; Anferov, V. A.; Blinov, B. B.; Chu, C. M.; Caussyn, D. D.; Courant, E. D.; Gladycheva, S. E.; Hu, S.; Krisch, A. D.; Nurushev, T. S.; Phelps, R. A.; Ratner, L. G.; Varzar, S. M.; Wong, V. K.; Derbenev, Ya. S.; Lee, S. Y.; Rinckel, T.; Schwandt, P.; Sperisen, F.; Stephenson, E. J.; von Przewoski, B.; Baiod, R.; Russell, A. D.; Ohmori, C.; Sato, H.

    1996-05-01

    Partial Siberian snakes are effective in overcoming imperfection depolarizing resonances, but they may also change the crossing energy for intrinsic depolarizing resonances. We experimentally investigated the effect of a partial Siberian snake near intrinsic depolarizing resonances with stored 140 MeV and 160 MeV polarized proton beams. Using various partial Siberian snake strengths up to 30%, depolarization was observed; this may be due to a change in the spin precession frequency which moves the energy of nearby intrinsic depolarizing resonances.

  12. Gamma knife surgery for craniopharyngioma.

    PubMed

    Prasad, D; Steiner, M; Steiner, L

    1995-01-01

    We present our results of Gamma Knife surgery for craniopharyngioma in nine patients. The current status of surgery, radiation therapy, intracavitary instillation of radionucleides and Gamma Knife surgery in the management of craniopharyngiomas is discussed.

  13. Intracranial Hypertension: Medication and Surgery

    MedlinePlus

    ... Intracraneal en Espanol. STORE Shop the IHRF Store Medication and Surgery Medication and Surgery Both drugs and surgery are used ... to treat the headache that accompanies chronic IH. Medications for chronic headache like tricyclic anti-depressants, beta- ...

  14. Surgery for Stress Urinary Incontinence

    MedlinePlus

    ... Events Advocacy For Patients About ACOG Surgery for Stress Urinary Incontinence Home For Patients Search FAQs Surgery ... Incontinence FAQ166, July 2014 PDF Format Surgery for Stress Urinary Incontinence Special Procedures What is stress urinary ...

  15. Tests and visits before surgery

    MedlinePlus

    Before surgery - tests; Before surgery - doctor visits ... Pre-op is the time before your surgery. It means "before operation." During this time, you will meet with one of your doctors. This may be your surgeon or primary care ...

  16. Preparing for Breast Reconstruction Surgery

    MedlinePlus

    ... Cancer Breast Reconstruction Surgery Preparing for Breast Reconstruction Surgery Your surgeon can help you know what to ... The plan for follow-up Costs Understanding your surgery costs Health insurance policies often cover most or ...

  17. Hierarchical partial order ranking.

    PubMed

    Carlsen, Lars

    2008-09-01

    Assessing the potential impact on environmental and human health from the production and use of chemicals or from polluted sites involves a multi-criteria evaluation scheme. A priori several parameters are to address, e.g., production tonnage, specific release scenarios, geographical and site-specific factors in addition to various substance dependent parameters. Further socio-economic factors may be taken into consideration. The number of parameters to be included may well appear to be prohibitive for developing a sensible model. The study introduces hierarchical partial order ranking (HPOR) that remedies this problem. By HPOR the original parameters are initially grouped based on their mutual connection and a set of meta-descriptors is derived representing the ranking corresponding to the single groups of descriptors, respectively. A second partial order ranking is carried out based on the meta-descriptors, the final ranking being disclosed though average ranks. An illustrative example on the prioritization of polluted sites is given.

  18. Partially integrated exhaust manifold

    SciTech Connect

    Hayman, Alan W; Baker, Rodney E

    2015-01-20

    A partially integrated manifold assembly is disclosed which improves performance, reduces cost and provides efficient packaging of engine components. The partially integrated manifold assembly includes a first leg extending from a first port and terminating at a mounting flange for an exhaust gas control valve. Multiple additional legs (depending on the total number of cylinders) are integrally formed with the cylinder head assembly and extend from the ports of the associated cylinder and terminate at an exit port flange. These additional legs are longer than the first leg such that the exit port flange is spaced apart from the mounting flange. This configuration provides increased packaging space adjacent the first leg for any valving that may be required to control the direction and destination of exhaust flow in recirculation to an EGR valve or downstream to a catalytic converter.

  19. Activated partial thromboplastin time.

    PubMed

    Ignjatovic, Vera

    2013-01-01

    Activated partial thromboplastin time (APTT) is a commonly used coagulation assay that is easy to perform, is affordable, and is therefore performed in most coagulation laboratories, both clinical and research, worldwide. The APTT is based on the principle that in citrated plasma, the addition of a platelet substitute, factor XII activator, and CaCl2 allows for formation of a stable clot. The time required for the formation of a stable clot is recorded in seconds and represents the actual APTT result.

  20. [Surgery for thoracic tuberculosis].

    PubMed

    Kilani, T; Boudaya, M S; Zribi, H; Ouerghi, S; Marghli, A; Mestiri, T; Mezni, F

    2015-01-01

    Tuberculosis is mainly a medical disease. Surgery has been the unique therapeutic tool for a long time before the advent of specific antituberculous drugs, and the role of surgery was then confined to the treatment of the sequelae of tuberculosis and their complications. The resurgence of tuberculosis and the emergence of multidrug-resistant TB combined to immunosuppressed patients represent a new challenge for tuberculosis surgery. Surgery may be indicated for a diagnostic purpose in patients with pulmonary, pleural, mediastinal or thoracic wall involvement, or with a therapeutic purpose (drainage, resection, residual cavity obliteration). Modern imaging techniques and the advent of video-assisted thoracic surgery allowed a new approach of this pathology; the majority of diagnostic interventions and selected cases requiring lung resection can be performed through a mini-invasive approach. Patients proposed for aggressive surgery may be treated with the best results thanks to a good evaluation of the thoracic lesions, of the patients' nutritional, infectious and general status combined with a good coordination between the specialized medical team for an optimal preparation to surgery.

  1. Anti-reflux surgery - children

    MedlinePlus

    ... reflux disease. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics . 19th ed. Philadelphia, ... surgery - children - discharge Anti-reflux surgery - discharge ...

  2. Surgery induced immunosuppression.

    PubMed

    Hogan, Brian V; Peter, Mark B; Shenoy, Hrishikesh G; Horgan, Kieran; Hughes, Thomas A

    2011-02-01

    Surgery and anaesthesia result in a variety of metabolic and endocrine responses, which result in a generalised state of immunosuppression in the immediate post-operative period. Surgery induced immunosuppression has been implicated in the development of post-operative septic complications and tumour metastasis formation. In addition the effectiveness of many treatments in the adjuvant setting is dependent on a functioning immune system. By understanding the mechanisms contributing to surgery-induced immunosuppression, surgeons may undertake strategies to minimise its effect and reduce potential short-term and long-term consequences to patients.

  3. Safe Surgery Trainer

    DTIC Science & Technology

    2014-08-15

    CDRL A001 For: Safe Surgery Trainer Prime Contract: N00014-14-C-0066 For the Period July 1, 2014 to July 31, 2014 Submitted: 15 August...DATE 15 AUG 2014 2. REPORT TYPE 3. DATES COVERED 01-07-2014 to 31-07-2014 4. TITLE AND SUBTITLE Safe Surgery Trainer 5a. CONTRACT NUMBER 5b... Surgery Trainer ONR N00014-14-C-0066 1 July 2014 to 31 July 2014 Unclassified 15 August 2014 Unclassified Use or disclosure of the data contained

  4. Transoral robotic thyroid surgery

    PubMed Central

    Clark, James H.; Kim, Hoon Yub

    2015-01-01

    There is currently significant demand for minimally invasive thyroid surgery; however the majority of proposed surgical approaches necessitate a compromise between minimal tissue dissection with a visible cervical scar or extensive tissue dissection with a remote, hidden scar. The development of transoral endoscopic thyroid surgery however provides an approach which is truly minimally invasive, as it conceals the incision within the oral cavity without significantly increasing the amount of required dissection. The transoral endoscopic approach however presents multiple technical challenges, which could be overcome with the incorporation of a robotic operating system. This manuscript summarizes the literature on the feasibility and current clinical experience with transoral robotic thyroid surgery. PMID:26425456

  5. Standing equine sinus surgery.

    PubMed

    Barakzai, Safia Z; Dixon, Padraic M

    2014-04-01

    Trephination of the equine sinuses is a common surgical procedure in sedated standing horses. Standing sinus flap surgery has become increasingly popular in equine referral hospitals and offers several advantages over sinusotomy performed under general anesthesia, including reduced patient-associated risks and costs; less intraoperative hemorrhage, allowing better visualization of the operative site; and allows surgeons to take their time. Other minimally invasive surgical procedures include sinoscopic surgery, balloon sinuplasty, and transnasal laser sinonasal fenestration. Despite the procedure used, appropriate indications for surgery, good patient selection, and familiarity with regional anatomy and surgical techniques are imperative for good results.

  6. Safe Surgery Trainer

    DTIC Science & Technology

    2015-02-20

    CDRL A001 For: Safe Surgery Trainer Prime Contract: N00014-14-C-0066 For the Period Jan 1, 2014 to Jan 31, 2014 Submitted: 20 February...control number. 1. REPORT DATE FEB 2015 2. REPORT TYPE 3. DATES COVERED 00-01-2015 to 00-01-2015 4. TITLE AND SUBTITLE Safe Surgery Trainer...Progress Report – ONR Safe Surgery Trainer ONR N00014-14-C-0066 Unclassified Unclassified Use or disclosure of the data contained on this page is

  7. Safe Surgery Trainer

    DTIC Science & Technology

    2015-06-15

    CDRL A001 For: Safe Surgery Trainer Prime Contract: N00014-14-C-0066 For the Period May, 2015 to May 31, 2015 Submitted: 15 June 2015...15 JUN 2015 2. REPORT TYPE 3. DATES COVERED 00-05-2015 to 31-05-2015 4. TITLE AND SUBTITLE Safe Surgery Trainer 5a. CONTRACT NUMBER 5b...ABSTRACT unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Progress Report – ONR Safe Surgery

  8. Safe Surgery Trainer

    DTIC Science & Technology

    2015-03-15

    CDRL A001 For: Safe Surgery Trainer Prime Contract: N00014-14-C-0066 For the Period Feb 1, 2014 to Feb 28, 2014 Submitted: 15 March 2015...DATE MAR 2015 2. REPORT TYPE 3. DATES COVERED 01-02-2014 to 28-02-2014 4. TITLE AND SUBTITLE Safe Surgery Trainer 5a. CONTRACT NUMBER 5b...COVERED 01-02-2014 to 28-02-2014 4. TITLE AND SUBTITLE Safe Surgery Trainer 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6

  9. Safe Surgery Trainer

    DTIC Science & Technology

    2015-05-15

    CDRL A001 For: Safe Surgery Trainer Prime Contract: N00014-14-C-0066 For the Period Mar 1, 2014 to Mar 31, 2014 Submitted: 15 May 2015...15 MAY 2015 2. REPORT TYPE 3. DATES COVERED 01-03-2014 to 31-03-2014 4. TITLE AND SUBTITLE Safe Surgery Trainer 5a. CONTRACT NUMBER 5b... Surgery Trainer ONR N00014-14-C-0066 Unclassified Unclassified Use or disclosure of the data contained on this page is subject to the restriction on

  10. Safe Surgery Trainer

    DTIC Science & Technology

    2015-04-15

    CDRL A001 For: Safe Surgery Trainer Prime Contract: N00014-14-C-0066 For the Period Mar 1, 2014 to Mar 31, 2014 Submitted: 15 April 2015...DATE 15 APR 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Safe Surgery Trainer 5a. CONTRACT NUMBER 5b... Surgery Trainer ONR N00014-14-C-0066 Unclassified Unclassified Use or disclosure of the data contained on this page is subject to the restriction

  11. [Robotics in general surgery: personal experience, critical analysis and prospectives].

    PubMed

    Fracastoro, Gerolamo; Borzellino, Giuseppe; Castelli, Annalisa; Fiorini, Paolo

    2005-01-01

    Today mini invasive surgery has the chance to be enhanced with sophisticated informative systems (Computer Assisted Surgery, CAS) like robotics, tele-mentoring and tele-presence. ZEUS and da Vinci, present in more than 120 Centres in the world, have been used in many fields of surgery and have been tested in some general surgical procedures. Since the end of 2003, we have performed 70 experimental procedures and 24 operations of general surgery with ZEUS robotic system, after having properly trained 3 surgeons and the operating room staff. Apart from the robot set-up, the mean operative time of the robotic operations was similar to the laparoscopic ones; no complications due to robotic technique occurred. The Authors report benefits and disadvantages related to robots' utilization, problems still to be solved and the possibility to make use of them with tele-surgery, training and virtual surgery.

  12. Partial transpose criteria for symmetric states

    NASA Astrophysics Data System (ADS)

    Bohnet-Waldraff, F.; Braun, D.; Giraud, O.

    2016-10-01

    We express the positive-partial-transpose (PPT) separability criterion for symmetric states of multiqubit systems in terms of matrix inequalities based on the recently introduced tensor representation for spin states. We construct a matrix from the tensor representation of the state and show that it is similar to the partial transpose of the density matrix written in the computational basis. Furthermore, the positivity of this matrix is equivalent to the positivity of a correlation matrix constructed from tensor products of Pauli operators. This allows for a more transparent experimental interpretation of the PPT criteria for an arbitrary spin-j state. The unitary matrices connecting our matrix to the partial transpose of the state generalize the so-called magic basis that plays a central role in Wootters' explicit formula for the concurrence of a two-qubit system and the Bell bases used for the teleportation of a one- or two-qubit state.

  13. Partial Southwest Elevation Mill #5 West (Part 3), Partial ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Partial Southwest Elevation - Mill #5 West (Part 3), Partial Southwest Elevation - Mill #5 West (with Section of Courtyard) (Parts 1 & 2) - Boott Cotton Mills, John Street at Merrimack River, Lowell, Middlesex County, MA

  14. Paternalism and partial autonomy.

    PubMed Central

    O'Neill, O

    1984-01-01

    A contrast is often drawn between standard adult capacities for autonomy, which allow informed consent to be given or withheld, and patients' reduced capacities, which demand paternalistic treatment. But patients may not be radically different from the rest of us, in that all human capacities for autonomous action are limited. An adequate account of paternalism and the role that consent and respect for persons can play in medical and other practice has to be developed within an ethical theory that does not impose an idealised picture of unlimited autonomy but allows for the variable and partial character of actual human autonomy. PMID:6520849

  15. Surgery for Cervical Cancer

    MedlinePlus

    ... of watery brown discharge for a few weeks. Laser surgery A focused laser beam, directed through the vagina, is used to ... cervix. This is done using a surgical or laser knife (cold knife cone biopsy) or using a ...

  16. Expectations of Sinus Surgery

    MedlinePlus

    ... after surgery, it can be treated with antibiotics. Steroids - One of the underlying causes of some forms ... forms of swelling, your doctor may prescribe oral steroids or topical (spray, irrigation) steroids or both. Packing – ...

  17. Brain surgery - discharge

    MedlinePlus

    ... to take these medicines. If you had a brain aneurysm , you may also have other symptoms or problems. ... chap 28. Read More Acoustic neuroma Brain abscess Brain aneurysm repair Brain surgery Brain tumor - children Brain tumor - ...

  18. Preparing for Surgery

    MedlinePlus

    ... for you before, during, and after your operation. Nurses will assist your doctor during surgery, perform special ... you are stable. As soon as possible, your nurses will have you move around as much as ...

  19. Hemostasis and Hepatic Surgery.

    PubMed

    Eeson, Gareth; Karanicolas, Paul J

    2016-04-01

    Operative blood loss is a major source of morbidity and even mortality for patients undergoing hepatic resection. This review discusses strategies to minimize blood loss and the utilization of allogeneic blood transfusion pertaining to oncologic hepatic surgery.

  20. Cataract surgery - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100079.htm Cataract surgery - series—Normal anatomy To use the sharing ... lens of an eye is normally clear. A cataract is when the lens becomes cloudy as you ...

  1. Carotid artery surgery - discharge

    MedlinePlus

    ... removed. The skin incision was closed with surgical tape. During your surgery, your heart and brain activity ... get home. It is ok if the surgical tape on your incision gets wet. DO NOT soak, ...

  2. Oophorectomy (Ovary Removal Surgery)

    MedlinePlus

    ... also be robotically assisted in certain cases. During robotic surgery, the surgeon watches a 3-D monitor ... Whether your oophorectomy is an open, laparoscopic or robotic procedure depends on your situation. Laparoscopic or robotic ...

  3. Hemorrhoid surgery - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100026.htm Hemorrhoid surgery - series—Normal anatomy To use the sharing ... empties stool from the body through the anus. Hemorrhoids are "cushions" of tissue filled with blood vessels ...

  4. American Board of Surgery

    MedlinePlus

    ... representatives from five major regional vascular surgery societies. Mar. 27, 2017 ABS Seeks New Executive Director The ... in Philadelphia. Applications are due by May 1. Mar. 10, 2017 E-News - Winter 2017 The latest ...

  5. Carotid artery surgery - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100124.htm Carotid artery surgery - series—Normal anatomy To use the sharing ... out of 4 Overview There are four carotid arteries, with a pair located on each side of ...

  6. Deep breathing after surgery

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000440.htm Deep breathing after surgery To use the sharing features on ... way to do so is by doing deep breathing exercises. Deep breathing keeps your lungs well-inflated ...

  7. Retrosternal thyroid surgery

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/007558.htm Retrosternal thyroid surgery To use the sharing features on this page, please enable JavaScript. The thyroid gland is normally located at the front of ...

  8. Transanal Minimally Invasive Surgery

    PubMed Central

    deBeche-Adams, Teresa; Nassif, George

    2015-01-01

    Transanal minimally invasive surgery (TAMIS) was first described in 2010 as a crossover between single-incision laparoscopic surgery and transanal endoscopic microsurgery (TEM) to allow access to the proximal and mid-rectum for resection of benign and early-stage malignant rectal lesions. The TAMIS technique can also be used for noncurative intent surgery of more advanced lesions in patients who are not candidates for radical surgery. Proper workup and staging should be done before surgical decision-making. In addition to the TAMIS port, instrumentation and set up include readily available equipment found in most operating suites. TAMIS has proven its usefulness in a wide range of applications outside of local excision, including repair of rectourethral fistula, removal of rectal foreign body, control of rectal hemorrhage, and as an adjunct in total mesorectal excision for rectal cancer. TAMIS is an easily accessible, technically feasible, and cost-effective alternative to TEM. PMID:26491410

  9. Types of Heart Surgery

    MedlinePlus

    ... conditions that make open-heart surgery very risky. Arrhythmia Treatment An arrhythmia (ah-RITH-me-ah) is a problem with ... rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, ...

  10. Blood donation before surgery

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000367.htm Blood donation before surgery To use the sharing features ... vessels. Several sources of blood are described here. Blood From the Public (Volunteer Blood Donation) The most ...

  11. Surgery for Pancreatic Cancer

    MedlinePlus

    ... but the goal is not to try to cure the cancer. Staging laparoscopy To determine which type of surgery ... the planned operation would be very unlikely to cure the cancer and could still lead to major side effects. ...

  12. Septoplasty and Turbinate Surgery

    MedlinePlus

    ... nose. Surgery on the septum can lead to stretching or injury to these nerves. This can lead ... a painless procedure that is performed in our office. A small endoscope is used to visualize the ...

  13. Breast augmentation surgery

    MedlinePlus

    ... the shape of your breasts. Talk with a plastic surgeon if you are considering breast augmentation. Discuss ... mammograms or breast x-rays before surgery. The plastic surgeon will do a routine breast exam. Several ...

  14. Heart bypass surgery - discharge

    MedlinePlus

    ... Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest . 2012;141(2 ... surgery Heart failure - overview High blood cholesterol levels Smoking - ...

  15. Cosmetic surgery: medicolegal considerations

    PubMed Central

    Piras, Mauro; Delbon, Paola; Conti, Adelaide; Capasso, Emanuele; Niola, Massimo; Bin, Paola

    2016-01-01

    Abstract Cosmetic surgery is one of the two branches of plastic surgery. The characteristic of non-necessity of this surgical speciality implies an increased severity in the evaluation of the risk-benefit balance. Therefore, great care must be taken in providing all the information necessary in order to obtain valid consent to the intervention. We analyzed judgments concerning cosmetic surgery found in national legal databases. A document of National Bioethics Committee (CNB) was also analyzed. Conclusion: The receipt of valid, informed consent is of absolute importance not only to legitimise the medical-surgical act, but it also represents the key element in the question concerning the existence of an obligation to achieve certain results/use of certain methods in the cosmetic surgery. PMID:28352816

  16. Brain Tumor Surgery

    MedlinePlus

    ... The surgical removal of a portion of the skull. Doing so allows the neurosurgeon to find the ... much of it as possible. The piece of skull that was removed is replaced following surgery. Craniectomy: ...

  17. Robotics in Colorectal Surgery

    PubMed Central

    Weaver, Allison; Steele, Scott

    2016-01-01

    Over the past few decades, robotic surgery has developed from a futuristic dream to a real, widely used technology. Today, robotic platforms are used for a range of procedures and have added a new facet to the development and implementation of minimally invasive surgeries. The potential advantages are enormous, but the current progress is impeded by high costs and limited technology. However, recent advances in haptic feedback systems and single-port surgical techniques demonstrate a clear role for robotics and are likely to improve surgical outcomes. Although robotic surgeries have become the gold standard for a number of procedures, the research in colorectal surgery is not definitive and more work needs to be done to prove its safety and efficacy to both surgeons and patients. PMID:27746895

  18. Ear surgery - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100016.htm Ear surgery - series—Normal anatomy To use the sharing ... Overview This image demonstrates normal appearance of the ears in relation to the face. Review Date 10/ ...

  19. Anesthesia for bench surgery.

    PubMed

    Sachin, S; Rajesh, M C; Ramdas, E K

    2016-01-01

    Surgical removal of the kidney tumor outside the body, (ex vivo renal bench surgery) followed by auto transplantation is an emerging and often done procedure to reconstruct the urinary tract. It possesses immense challenges to both the anesthesiologists and the surgeons. The risks are multiplied if you are performing the surgery on a solitary functioning kidney. Here, we are describing the anesthetic management of 70-year-old male post nephrectomy patient undergoing renal auto transplantation by bench surgery. Our primary goals for perioperative management were to maintain a stable hemodynamics throughout the procedure, to reduce fluid overload during the period of extracorporeal surgery, to maintain perfusion for the transplanted solitary kidney, to control bleeding to a minimum, and to provide adequate analgesia for the patient. We made use of a balanced anesthetic technique and stringent monitoring standards to bring forth a successful outcome for the patient. At the end of his hospital stay, patient went home with a healthy, normally functioning kidney.

  20. Heart bypass surgery - slideshow

    MedlinePlus

    ... 24/2016 Updated by: Mary C. Mancini, MD, PhD, Department of Surgery, Louisiana State University Health Sciences ... reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team. ...

  1. Orthognathic Surgery: General Considerations

    PubMed Central

    Khechoyan, David Y.

    2013-01-01

    Orthognathic surgery is a unique endeavor in facial surgery: a patient's appearance and occlusal function can be improved significantly, impacting the patient's sense of self and well-being. Successful outcomes in modern orthognathic surgery rely on close collaboration between the surgeon and the orthodontist across all stages of treatment, from preoperative planning to finalization of occlusion. Virtual computer planning promotes a more accurate analysis of dentofacial deformity and preoperative planning. It is also an invaluable aid in providing comprehensive patient education. In this article, the author describes the general surgical principles that underlie orthognathic surgery, highlighting the sequence of treatment, preoperative analysis of dentofacial deformity, surgical execution of the treatment plan, and possible complications. PMID:24872758

  2. Robot-assisted partial nephrectomy: current perspectives and future prospects.

    PubMed

    Gautam, Gagan; Benway, Brian M; Bhayani, Sam B; Zorn, Kevin C

    2009-10-01

    The widespread adoption of laparoscopic partial nephrectomy (LPN) has been curtailed by its technical complexity. With the introduction of robotic technology, there is a potential for a shorter learning curve for minimally invasive nephron-sparing surgery (NSS). Initial published data on robot-assisted partial nephrectomy show promising perioperative outcomes comparable to large LPN series performed by highly experienced laparoscopic surgeons. Intraoperative parameters (operating room time, warm ischemia time, and blood loss) and short-term oncologic results demonstrate that this technique, unlike LPN, has a relatively short learning curve. Economic factors, as well as the necessity of an experienced bedside assistant, present the potential shortcomings of the procedure.

  3. Experts' Understanding of Partial Derivatives Using the Partial Derivative Machine

    ERIC Educational Resources Information Center

    Roundy, David; Weber, Eric; Dray, Tevian; Bajracharya, Rabindra R.; Dorko, Allison; Smith, Emily M.; Manogue, Corinne A.

    2015-01-01

    Partial derivatives are used in a variety of different ways within physics. Thermodynamics, in particular, uses partial derivatives in ways that students often find especially confusing. We are at the beginning of a study of the teaching of partial derivatives, with a goal of better aligning the teaching of multivariable calculus with the needs of…

  4. Bariatric surgery outcomes.

    PubMed

    Dumon, Kristoffel R; Murayama, Kenric M

    2011-12-01

    Obesity is associated with an increased risk of death, and morbid obesity carries a significant risk of life-threatening complications such as heart disease, diabetes, and high blood pressure. Bariatric surgery is recognized as the only effective treatment of morbid obesity. The estimated number of bariatric operations performed in the United States in 2008 was more than 13 times the number performed in 1992. Despite this increase, only 1% of the eligible morbidly obese population are currently treated with bariatric surgery.

  5. Neurological surgery planning system

    NASA Astrophysics Data System (ADS)

    Jiang, Charlie Z. W.; Zamorano, Lucia J.; Kadi, A. Majeed

    1993-09-01

    The computer-assisted neurological surgery planning system (NSPS), developed by the Neurological Surgery Department, Wayne State University, Detroit, MI, is designed to offer neurosurgeons a safe and accurate method to approach intracranial lesions. Software consisting of the most advanced technologies in computer vision, computer graphics, and stereotactic numeric analysis forms the kernel of the system. Our paper discusses the functionalities and background theories used in NSPS.

  6. Photobiomodulation in laser surgery

    NASA Astrophysics Data System (ADS)

    Liu, Timon Cheng-Yi; Rong, Dong-Liang; Huang, Jin; Deng, Xiao-Yuan; Liu, Song-Hao

    2006-01-01

    Laser surgery provides good exposure with clear operating fields and satisfactory preliminary functional results. In contrast to conventional excision, it was found that matrix metalloproteinases and the tissue inhibitors of metalloproteinases -1 mRNA expression is higher, myofibroblasts appeared and disappeared slower in laser excision wounds. It has been suggested that the better anatomical and functional results achieved following laser cordectomy may be explained by the fact that such procedures result in better, more rapid healing processes to recover vocal cord for early glottic tumors and better. In this paper, the role of photobiomodulation in laser surgery will be discussed by the cultured monolayer normal human skin fibroblast model of the photobiomodulation of marginal irradiation of high intensity laser beam, the photobiomodulation related to the irradiated tissue, the biological information model of photobiomodulation and the animal models of laser surgery. Although high intensity laser beam is so intense that it destroys the irradiated cells or tissue, its marginal irradiation intensity is so low that there is photobiomodulation on non-damage cells to modulate the regeneration of partly damaged tissue so that the surgery of laser of different parameters results in different post-surgical recovery. It was concluded that photobiomodulation might play an important role in the long-term effects of laser surgery, which might be used to design laser surgery.

  7. Surgery for childhood epilepsy

    PubMed Central

    Jayalakshmi, Sita; Panigrahi, Manas; Nanda, Subrat Kumar; Vadapalli, Rammohan

    2014-01-01

    Approximately 60% of all patients with epilepsy suffer from focal epilepsy syndromes. In about 15% of these patients, the seizures are not adequately controlled with antiepileptic drugs; such patients are potential candidates for surgical treatment and the major proportion is in the pediatric group (18 years old or less). Epilepsy surgery in children who have been carefully chosen can result in either seizure freedom or a marked (>90%) reduction in seizures in approximately two-thirds of children with intractable seizures. Advances in structural and functional neuroimaging, neurosurgery, and neuroanaesthesia have improved the outcomes of surgery for children with intractable epilepsy. Early surgery improves the quality of life and cognitive and developmental outcome and allows the child to lead a normal life. Surgically remediable epilepsies should be identified early and include temporal lobe epilepsy with hippocampal sclerosis, lesional temporal and extratemporal epilepsy, hemispherical epilepsy, and gelastic epilepsy with hypothalamic hamartoma. These syndromes have both acquired and congenital etiologies and can be treated by resective or disconnective surgery. Palliative procedures are performed in children with diffuse and multifocal epilepsies who are not candidates for resective surgery. The palliative procedures include corpus callosotomy and vagal nerve stimulation while deep brain stimulation in epilepsy is still under evaluation. For children with “surgically remediable epilepsy,” surgery should be offered as a procedure of choice rather than as a treatment of last resort. PMID:24791093

  8. Robotic surgery in gynecology

    PubMed Central

    Sinha, Rooma; Sanjay, Madhumati; Rupa, B.; Kumari, Samita

    2015-01-01

    FDA approved Da Vinci Surgical System in 2005 for gynecological surgery. It has been rapidly adopted and it has already assumed an important position at various centers where this is available. It comprises of three components: A surgeon's console, a patient-side cart with four robotic arms and a high-definition three-dimensional (3D) vision system. In this review we have discussed various robotic-assisted laparoscopic benign gynecological procedures like myomectomy, hysterectomy, endometriosis, tubal anastomosis and sacrocolpopexy. A PubMed search was done and relevant published studies were reviewed. Surgeries that can have future applications are also mentioned. At present most studies do not give significant advantage over conventional laparoscopic surgery in benign gynecological disease. However robotics do give an edge in more complex surgeries. The conversion rate to open surgery is lesser with robotic assistance when compared to laparoscopy. For myomectomy surgery, Endo wrist movement of robotic instrument allows better and precise suturing than conventional straight stick laparoscopy. The robotic platform is a logical step forward to laparoscopy and if cost considerations are addressed may become popular among gynecological surgeons world over. PMID:25598600

  9. Cardioprotection during cardiac surgery

    PubMed Central

    Hausenloy, Derek J.; Boston-Griffiths, Edney; Yellon, Derek M.

    2012-01-01

    Coronary heart disease (CHD) is the leading cause of morbidity and mortality worldwide. For a large number of patients with CHD, coronary artery bypass graft (CABG) surgery remains the preferred strategy for coronary revascularization. Over the last 10 years, the number of high-risk patients undergoing CABG surgery has increased significantly, resulting in worse clinical outcomes in this patient group. This appears to be related to the ageing population, increased co-morbidities (such as diabetes, obesity, hypertension, stroke), concomitant valve disease, and advances in percutaneous coronary intervention which have resulted in patients with more complex coronary artery disease undergoing surgery. These high-risk patients are more susceptible to peri-operative myocardial injury and infarction (PMI), a major cause of which is acute global ischaemia/reperfusion injury arising from inadequate myocardial protection during CABG surgery. Therefore, novel therapeutic strategies are required to protect the heart in this high-risk patient group. In this article, we review the aetiology of PMI during CABG surgery, its diagnosis and clinical significance, and the endogenous and pharmacological therapeutic strategies available for preventing it. By improving cardioprotection during CABG surgery, we may be able to reduce PMI, preserve left ventricular systolic function, and reduce morbidity and mortality in these high-risk patients with CHD. PMID:22440888

  10. Is Titan Partially Differentiated?

    NASA Astrophysics Data System (ADS)

    Mitri, G.; Pappalardo, R. T.; Stevenson, D. J.

    2009-12-01

    The recent measurement of the gravity coefficients from the Radio Doppler data of the Cassini spacecraft has improved our knowledge of the interior structure of Titan (Rappaport et al. 2008 AGU, P21A-1343). The measured gravity field of Titan is dominated by near hydrostatic quadrupole components. We have used the measured gravitational coefficients, thermal models and the hydrostatic equilibrium theory to derive Titan's interior structure. The axial moment of inertia gives us an indication of the degree of the interior differentiation. The inferred axial moment of inertia, calculated using the quadrupole gravitational coefficients and the Radau-Darwin approximation, indicates that Titan is partially differentiated. If Titan is partially differentiated then the interior must avoid melting of the ice during its evolution. This suggests a relatively late formation of Titan to avoid the presence of short-lived radioisotopes (Al-26). This also suggests the onset of convection after accretion to efficiently remove the heat from the interior. The outer layer is likely composed mainly of water in solid phase. Thermal modeling indicates that water could be present also in liquid phase forming a subsurface ocean between an outer ice I shell and a high pressure ice layer. Acknowledgments: This work was conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

  11. Furnace brazing under partial vacuum

    NASA Technical Reports Server (NTRS)

    Mckown, R. D.

    1979-01-01

    Brazing furnace utilizing partial-vacuum technique reduces tooling requirements and produces better bond. Benefit in that partial vacuum helps to dissociate metal oxides that inhibit metal flow and eliminates heavy tooling required to hold parts together during brazing.

  12. A new dimension in endo surgery: Micro endo surgery

    PubMed Central

    Pecora, Gabriele Edoardo; Pecora, Camilla Nicole

    2015-01-01

    There is an immense difference between tradizional Endodontic Surgery and Micro-Endo Surgery. Microsurgical techniques made possible and accessible results,that were unimaginable before. Under microscopic control,the operative techniques reached continous changes,allowing a better precision and quality standards. The dramatic evolution from Endo Surgery to Micro-Endo Surgery has enlarged the horizon of therapeutic options. Illumination and magnification through the Microscope has fundamentally and radically changed the way endo surgery can be performed. PMID:25657519

  13. Partial Return Yoke for MICE Step IV and Final Step

    SciTech Connect

    Witte, Holger; Plate, Stephen; Berg, J.Scott; Tarrant, Jason; Bross, Alan

    2015-06-01

    This paper reports on the progress of the design and construction of a retro-fitted return yoke for the international Muon Ionization Cooling Experiment (MICE). MICE is a proof-of-principle experiment aiming to demonstrate ionization cooling experimentally. In earlier studies we outlined how a partial return yoke can be used to mitigate stray magnetic field in the experimental hall; we report on the progress of the construction of the partial return yoke for MICE Step IV. We also discuss an extension of the Partial Return Yoke for the final step of MICE; we show simulation results of the expected performance.

  14. Laparoscopic Surgery - What Is It?

    MedlinePlus

    ... Surgery - What is it? Laparoscopic Surgery - What is it? Laparoscopic Surgery - What is it? | ASCRS WHAT IS LAPAROSCOPIC SURGERY? Laparoscopic or “minimally ... information about the management of the conditions addressed. It should be recognized that these brochures should not ...

  15. Progressive Paraparesis after CABG Surgery

    PubMed Central

    Shadvar, Kamran; Eslampoor, Yashar

    2013-01-01

    CABG is one of the most common cardiac surgeries all over the world. Similar to other surgeries, it may be associated with some undesirable complications including neurologic complications which might cause morbidity and mortality after surgery. We will describe a case of Progressive Paraparesis after CABG Surgery and review its etiology, diagnosis and management. PMID:24251008

  16. Ultrasound-based liver computer assisted surgery.

    PubMed

    Windyga, P; Hiransakolwong, N; Vu, K; Medina, R; Onik, G

    2004-01-01

    Ongoing research toward development of a computer-assisted, ultrasound-based software/hardware tool to improve instrument positioning in moving organs during minimally invasive abdominal surgery is presented. The main objective of this research is to calculate, in real time and without user intervention, the pre-/intra-operative 3D/2D image misalignment due to patient respiration and the shift induced by the surgical instrument. Our methodology applied to the particular case of the liver, and partial results related to the image registration approach, based on organ segmentation and shape description, are presented. Preliminary results are highly encouraging. Among other benefits, use of this tool will increase surgeon confidence and improve surgery outcomes.

  17. Partial androgen insensitivity syndrome with thermolability in the androgen receptor.

    PubMed

    Hiraoka, Kenji; Kawauchi, Akihiro; Soh, Jintetsu; Ohe, Hiroshi; Shima, Hiroki; Miki, Tsuneharu

    2006-01-01

    We report case of partial androgen insensitivity syndrome in a 12-year-old boy referred to our clinic complaining of bilateral gynecomastia and left undescended testicle. Laparoscopy for undescended testicle and bilateral mastectomy were performed, and the left testicle was absent. When skin fibroblasts of the scrotum obtained during surgery were cultured to analyse the androgen receptors, a slight thermolability was observed. Genomic examination of the androgen receptor gene could not detect any mutations.

  18. Risk factors influencing the outcome of strabismus surgery following retinal detachment surgery with scleral buckle

    PubMed Central

    Rabinowitz, Ronen; Velez, Federico G.; Pineles, Stacy L.

    2013-01-01

    Purpose To determine factors associated with surgical success in patients undergoing strabismus surgery after retinal detachment repair with scleral buckle. Methods The medical records of consecutive patients who underwent strabismus surgery after repair of retinal detachment with scleral buckle were retrospectively reviewed. A successful “motor” outcome was defined as horizontal deviation <10Δ and vertical deviation <4Δ in the primary position; successful “sensory” outcome was no diplopia in the primary position. Various factors such as removing the scleral buckle at the time of strabismus surgery, the macula structural status, size of the preoperative deviation, presence of restriction to passive movement, and whether the eye with the scleral buckle was the operated eye were compared among groups based on motor success. Results A total of 25 patients were included. The overall motor success rate was 72% after 1.8 ± 0.9 operations, with 62% of patients diplopia free in the primary position. Horizontal deviation <10Δ (P = 0.005) and minimal restriction on forced duction test were associated with motor success after the first surgery (P = 0.05). Partial or entire scleral buckle removal (n = 15) and fellow-eye surgery were not significantly correlated with motor success in our cohort. There were no retinal redetachments after scleral buckle removal. Conclusions A small preoperative horizontal deviation, and minimally restricted ocular rotations were associated with better results. Removing the scleral buckle did not improve results. PMID:24215808

  19. Bariatric surgery. Surgery for weight control in patients with morbid obesity.

    PubMed

    Balsiger, B M; Murr, M M; Poggio, J L; Sarr, M G

    2000-03-01

    Morbid obesity has become a health crisis in the United States. Medical programs developed at nonoperative attempts to lose (and maintain) an adequate weight loss are largely unsuccessful. Bariatric surgery has been proven to be effective at inducing and maintaining a satisfactory weight loss to decrease weight-related comorbidity. Bariatric operations include procedures that decrease mechanically the volume capacitance of the proximal stomach (vertical banded gastroplasty, laparoscopic gastric banding) or decrease the proximal gastric capacitance and establish a partial selective malabsorption (gastric bypass and its modifications, partial biliopancreatic bypass, and duodenal switch with partial biliopancreatic bypass). These operations should induce a loss of at least 50% (or more) of excess body weight. Not all patients are candidates for these procedures, and the best results are obtained by a multidisciplinary team (including nutritionist, physician, dietitian, psychologist or psychiatrist interested in eating disorders, and surgeon).

  20. Outlining the limits of partial nephrectomy

    PubMed Central

    Chopra, Sameer; Satkunasivam, Raj; Kundavaram, Chandan; Liang, Gangning

    2015-01-01

    Amongst nephron-sparing modalities, partial nephrectomy (PN) is the standard of care in the treatment of renal cell carcinoma (RCC). Despite the increasing utilization of PN, particularly propagated by robot-assisted, minimally invasive approaches for small renal masses (SRMs), the limits of PN appear to be also evolving. In this review, we sought to address the tumour stage beyond which PN may be oncologically perilous. While the evidence supports PN in the treatment of tumours < pT2a, PN may have a role in advanced or metastatic RCC. Other scenarios wherein PN has limited utility are also explored, including anatomical or surgical factors that dictate the difficulty of the case, such as prior renal surgery. Lastly, we discuss the emerging role of molecular biomarkers, specifically epigenetics, to aid in the risk stratification of SRMs and to select tumours optimally suited for PN. PMID:26236649

  1. Accelerated Partial Breast Irradiation in Clinical Practice

    PubMed Central

    Wenz, Frederik; Sedlmayer, Felix; Herskind, Carsten; Welzel, Grit; Sperk, Elena; Neumaier, Christian; Gauter-Fleckenstein, Benjamin; Vaidya, Jayant S.; Sütterlin, Marc

    2015-01-01

    Summary Accelerated partial breast irradiation (APBI) has been under clinical investigation for more than 15 years. There are several technical approaches that are clinically established, e.g. brachytherapy, intraoperative radiotherapy (IORT), or external-beam radiotherapy. The understanding of the underlying biology, optimal technical procedures, patient selection criteria, and imaging changes during follow-up has increased enormously. After completion of several phase III trials using brachytherapy or IORT, APBI is currently increasingly used either in phase IV studies, registries, or in selected patients outside of clinical studies. Consensus statements about suitable patients are available from several international and national societies like ASTRO, ESTRO, and DEGRO. One may expect that 15-25% of patients undergoing breast-conserving surgery may qualify for APBI, i.e. patients with small invasive ductal breast cancer without clinical lymph node involvement. PMID:26600760

  2. [New aspects in hernia surgery].

    PubMed

    Lammers, B J; Goretzki, P E; Otto, T

    2005-07-01

    In the last 10 years in Germany we have seen a lot of hernia repairs using mesh.Meta-analysis shows the advantages of using meshes in hernia surgery; recurrence rates in inguinal hernia surgery are less than 3% in studies. There is some discussion about minimally invasive surgery in Germany.In incisional hernia surgery there is no discussion about using meshes. The role of minimally invasive surgery has not yet been defined.

  3. Partially segmented deformable mirror

    DOEpatents

    Bliss, Erlan S.; Smith, James R.; Salmon, J. Thaddeus; Monjes, Julio A.

    1991-01-01

    A partially segmented deformable mirror is formed with a mirror plate having a smooth and continuous front surface and a plurality of actuators to its back surface. The back surface is divided into triangular areas which are mutually separated by grooves. The grooves are deep enough to make the plate deformable and the actuators for displacing the mirror plate in the direction normal to its surface are inserted in the grooves at the vertices of the triangular areas. Each actuator includes a transducer supported by a receptacle with outer shells having outer surfaces. The vertices have inner walls which are approximately perpendicular to the mirror surface and make planar contacts with the outer surfaces of the outer shells. The adhesive which is used on these contact surfaces tends to contract when it dries but the outer shells can bend and serve to minimize the tendency of the mirror to warp.

  4. Partially segmented deformable mirror

    DOEpatents

    Bliss, E.S.; Smith, J.R.; Salmon, J.T.; Monjes, J.A.

    1991-05-21

    A partially segmented deformable mirror is formed with a mirror plate having a smooth and continuous front surface and a plurality of actuators to its back surface. The back surface is divided into triangular areas which are mutually separated by grooves. The grooves are deep enough to make the plate deformable and the actuators for displacing the mirror plate in the direction normal to its surface are inserted in the grooves at the vertices of the triangular areas. Each actuator includes a transducer supported by a receptacle with outer shells having outer surfaces. The vertices have inner walls which are approximately perpendicular to the mirror surface and make planar contacts with the outer surfaces of the outer shells. The adhesive which is used on these contact surfaces tends to contract when it dries but the outer shells can bend and serve to minimize the tendency of the mirror to warp. 5 figures.

  5. Partial oxidation catalyst

    DOEpatents

    Krumpelt, Michael; Ahmed, Shabbir; Kumar, Romesh; Doshi, Rajiv

    2000-01-01

    A two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion. The dehydrogenation portion is a group VIII metal and the oxide-ion conducting portion is selected from a ceramic oxide crystallizing in the fluorite or perovskite structure. There is also disclosed a method of forming a hydrogen rich gas from a source of hydrocarbon fuel in which the hydrocarbon fuel contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion at a temperature not less than about 400.degree. C. for a time sufficient to generate the hydrogen rich gas while maintaining CO content less than about 5 volume percent. There is also disclosed a method of forming partially oxidized hydrocarbons from ethanes in which ethane gas contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion for a time and at a temperature sufficient to form an oxide.

  6. General surgery, translational lymphology and lymphatic surgery.

    PubMed

    Campisi, C; Witte, M H; Fulcheri, E; Campisi, C; Bellini, C; Villa, G; Campisi, C; Santi, P L; Parodi, A; Murdaca, G; Puppo, F; Boccardo, F

    2011-12-01

    A wide clinical experience in General Surgery has brought about a remarkable knowledge about lymphatic disorders both primary and secondary ones. Diagnostic and histopathological studies of lymphatic diseases allowed to better understand etiological aspects and pathophysiological mechanisms responsible of complex clinical features correlated to lymphatic dysfunctions. Translational lymphologic basic and clinical researches permitted to improve therapeutical approaches both from the medical and surgical point of view. Thus, strategies of treatment were proposed to prevent lymphatic injuries, to avoid lymphatic complications and to treat lymphatic diseases early in order to be able even to cure these pathologies.

  7. [Infratentorial hemorrhage following supratentorial surgery].

    PubMed

    Tomii, M; Nakajima, M; Ikeuchi, S; Ogawa, T; Abe, T

    1999-10-01

    Hemorrhage in regions remote from the site of initial intracranial operations is rare, but does occur. We report three cases of cerebellar hemorrhage that developed after supratentorial surgery, all of which had similar clinical findings and CT images. The first case was a 37-year-old man with a craniopharyngioma in the suprasellar lesion. Partial removal of the tumor was performed through frontal craniotomy and the translaminaterminals approach. A large quantity of cerebospinal fluid (CSF) was suctioned from the third ventricle during the operation, resulting in marked brain shrinkage. The second and third cases were 34- and 51-year-old women with unruptured right middle cerebral aneurysms. Clipping of the aneurysms through the pterional approach was performed in both cases. In the second case, CSF was suctioned in large quantity from the carotid and prechiasmal cistern at the operation, resulting in marked brain shrinkage. In the third case, however, only a small volume of CSF was suctioned from the carotid and prechiasmal cistern during the operation, and no marked brain shrinkage was observed. CT scan showed that the hematomas were located mainly in the subdural or the subarachnoid spaces over the cerebellar hemisphere and partially extending into the cerebellar cortex. The mechanism of cerebellar hemorrhage in these series of patients was thought to be multifactorial. The possible etiology for cerebellar hemorrhage in the three cases presented was examined, including the role of CSF suction during surgery and disturbance of venous circulation in the posterior fossa. Suction of the CSF may cause intracranial hypotension. Further reduction of intracranial pressure leads to an increased transluminal venous pressure. There was no episode of hypertension or disturbed blood coagulation during or after the operation. The preoperative angiogram also revealed no abnormality at the region of the posterior fossa. Neuroimaging of infratentorial hemorrhage after

  8. Gastrin and gastric surgery.

    PubMed

    Fabri, P J; McGuigan, J E

    1976-01-01

    The development of the radioimmunoassay for gastrin has resulted in significant increases in our knowledge of the physiology of the stomach and antrum, and in an objective recognition of the interaction of the gastrin and vagus mechanisms. Recent identification of multiple species of gastrin in the circulation, however, raises questions as to the significance of early experimental results. Until the various aspects of gastrin and their relative contributions in the normal state and in pathologic processes are identified, the significance of gastrin levels in the evaluation of patients with uncomplicated ulcer disease is unclear. Although many investigators have attempted to correlate changes in serum gastrin levels in response to various stimuli with the completeness of vagotomy or the likelihood of recurrence, it is too early to give any clinical significance to these reports. Several points in particular seem worthy of emphasis: 1. Preoperative serum gastrin levels are currently of no value in selecting an operation for the treatment of duodenal ulcer disease. 2. The difference in serum gastrin levels in response to feeding that may be shown to exist between groups of normal subjects and duodenal ulcer patients is not a value in diagnosing ulcer disease in a specific patient, nor in differentiating duodenal ulcer from other conditions. 3. The measurement of serum gastrin levels in association with Hollander tests, while perhaps of potential future benefit, does not improve the accuracy of the Hollander test nor do results necessarily relate to vagal innervation. 4. Postoperative serum gastrin levels are increased after vagotomy. The degree of hypergastrinemia after vagotomy does not correlate with risk of ulcer recurrence. 5. Hypergastrinemia (greater than 1000 pg. per ml.) in the presence of hyperacidity is essentially pathognomonic of the Zollinger-Ellison syndrome. Calcium and secretin infusions do not add to the diagnosis if clear-cut clinical and laboratory

  9. Robotic surgery in gynecology.

    PubMed

    Alkatout, Ibrahim; Mettler, Liselotte; Maass, Nicolai; Ackermann, Johannes

    2016-01-01

    Robotic surgery is the most dynamic development in the sector of minimally invasive operations currently. It should not be viewed as an alternative to laparoscopy, but as the next step in a process of technological evolution. The advancement of robotic surgery, in terms of the introduction of the Da Vinci Xi, permits the variable use of optical devices in all four trocars. Due to the new geometry of the "patient cart," an operation can be performed in all spatial directions without re-docking. Longer instruments and the markedly narrower mechanical elements of the "patient cart" provide greater flexibility as well as access similar to those of traditional laparoscopy. Currently, robotic surgery is used for a variety of indications in the treatment of benign gynecological diseases as well as malignant ones. Interdisciplinary cooperation and cooperation over large geographical distances have been rendered possible by telemedicine, and will ensure comprehensive patient care in the future by highly specialized surgery teams. In addition, the second operation console and the operation simulator constitute a new dimension in advanced surgical training. The disadvantages of robotic surgery remain the high costs of acquisition and maintenance as well as the laborious training of medical personnel before they are confident with using the technology.

  10. Computer Assisted Surgery

    NASA Astrophysics Data System (ADS)

    Arámbula Cosío, F.; Padilla Castañeda, M. A.

    2003-09-01

    Computer assisted surgery (CAS) systems can provide different levels of assistance to a surgeon during training and execution of a surgical procedure. This is done through the integration of : measurements taken on medical images; computer graphics techniques; and positioning or tracking mechanisms which accurately locate the surgical instruments inside the operating site. According to the type of assistance that is provided to the surgeon, CAS systems can be classified as: Image guided surgery systems; Assistant robots for surgery; and Training simulators for surgery. In this work are presented the main characteristics of CAS systems. It is also described the development of a computer simulator for training on Transurethral Resection of the Prostate (TURP) based on a computer model of the prostate gland which is able to simulate, in real time, deformations and resections of tissue. The model is constructed as a 3D mesh with physical properties such as elasticity. We describe the main characteristics of the prostate model and its performance. The prostate model will also be used in the development of a CAS system designed to assist the surgeon during a real TURP procedure. The system will provide 3D views of the shape of the prostate of the patient, and the position of the surgical instrument during the operation. The development of new computer graphics models which are able to simulate, in real time, the mechanical behavior of an organ during a surgical procedure, can improve significantly the training and execution of other minimally invasive surgical procedures such as laparoscopic gall bladder surgery.

  11. Robotic surgery in gynecology

    PubMed Central

    Alkatout, Ibrahim; Mettler, Liselotte; Maass, Nicolai; Ackermann, Johannes

    2016-01-01

    Robotic surgery is the most dynamic development in the sector of minimally invasive operations currently. It should not be viewed as an alternative to laparoscopy, but as the next step in a process of technological evolution. The advancement of robotic surgery, in terms of the introduction of the Da Vinci Xi, permits the variable use of optical devices in all four trocars. Due to the new geometry of the “patient cart,” an operation can be performed in all spatial directions without re-docking. Longer instruments and the markedly narrower mechanical elements of the “patient cart” provide greater flexibility as well as access similar to those of traditional laparoscopy. Currently, robotic surgery is used for a variety of indications in the treatment of benign gynecological diseases as well as malignant ones. Interdisciplinary cooperation and cooperation over large geographical distances have been rendered possible by telemedicine, and will ensure comprehensive patient care in the future by highly specialized surgery teams. In addition, the second operation console and the operation simulator constitute a new dimension in advanced surgical training. The disadvantages of robotic surgery remain the high costs of acquisition and maintenance as well as the laborious training of medical personnel before they are confident with using the technology. PMID:27990092

  12. Percutaneous forefoot surgery.

    PubMed

    Bauer, T

    2014-02-01

    Percutaneous methods can be used to perform many surgical procedures on the soft tissues and bones of the forefoot, thereby providing treatment options for all the disorders and deformities seen at this site. Theoretical advantages of percutaneous surgery include lower morbidity rates and faster recovery with immediate weight bearing. Disadvantages are the requirement for specific equipment, specific requirements for post-operative management, and lengthy learning curve. At present, percutaneous hallux valgus correction is mainly achieved with chevron osteotomy of the first metatarsal, for which internal fixation and a minimally invasive approach (2 cm incision) seem reliable and reproducible. This procedure is currently the focus of research and evaluation. Percutaneous surgery for hallux rigidus is simple and provides similar outcomes to those of open surgery. Lateral metatarsal malalignment and toe deformities are good indications for percutaneous treatment, which produces results similar to those of conventional surgery with lower morbidity rates. Finally, fifth ray abnormalities are currently the ideal indication for percutaneous surgery, given the simplicity of the procedure and post-operative course, high reliability, and very low rate of iatrogenic complications. The most commonly performed percutaneous techniques are described herein, with their current indications, main outcomes, and recent developments.

  13. Cardiac surgery 2015 reviewed.

    PubMed

    Doenst, Torsten; Strüning, Constanze; Moschovas, Alexandros; Gonzalez-Lopez, David; Essa, Yasin; Kirov, Hristo; Diab, Mahmoud; Faerber, Gloria

    2016-10-01

    For the year 2015, almost 19,000 published references can be found in PubMed when entering the search term "cardiac surgery". The last year has been again characterized by lively discussions in the fields where classic cardiac surgery and modern interventional techniques overlap. Lacking evidence in the field of coronary revascularization with either percutaneous coronary intervention or bypass surgery has been added. As in the years before, CABG remains the gold standard for the revascularization of complex stable triple-vessel disease. Plenty of new information has been presented comparing the conventional to transcatheter aortic valve implantation (TAVI) demonstrating similar short- and mid-term outcomes at high and low risk, but even a survival advantage with transfemoral TAVI at intermediate risk. In addition, there were many relevant and interesting other contributions from the purely operative arena. This review article will summarize the most pertinent publications in the fields of coronary revascularization, surgical treatment of valve disease, heart failure (i.e., transplantation and ventricular assist devices), and aortic surgery. While the article does not have the expectation of being complete and cannot be free of individual interpretation, it provides a condensed summary that is intended to give the reader "solid ground" for up-to-date decision-making in cardiac surgery.

  14. Innovations in Bariatric Surgery.

    PubMed

    Zhu, Catherine; Pryor, Aurora D

    2015-11-01

    Surgery has consistently been demonstrated to be the most effective long-term therapy for the treatment of obesity. However, despite excellent outcomes with current procedures, most patients with obesity- and weight-related comorbidities who meet criteria for surgical treatment choose not to pursue surgery out of fear of operative risks and complications or concerns about high costs. Novel minimally invasive procedures and devices may offer alternative solutions for patients who are hesitant to pursue standard surgical approaches. These procedures may be used for primary treatment of obesity, early intervention for patients approaching morbid obesity, temporary management prior to bariatric surgery, or revision of bypass surgery associated with weight regain. Novel bariatric procedures can in general be divided into four categories: endoluminal space-occupying devices, gastric suturing and restrictive devices, absorption-limiting devices, and neural-hormonal modulating devices. Many of these are only approved as short-term interventions, but these devices may be effective for patients desiring low-risk procedures or a transient effect. We will see the expansion of indications and alternatives for metabolic surgery as these techniques gain approval.

  15. Ancient technology in contemporary surgery.

    PubMed

    Buck, B A

    1982-03-01

    Archaeologists have shown that ancient man developed the ability to produce cutting blades of an extreme degree of sharpness from volcanic glass. The finest of these prismatic blades were produced in Mesoamerica about 2,500 years ago. The technique of production of these blades was rediscovered 12 years ago by Dr. Don Crabtree, who suggested possible uses for the blades in modern surgery. Blades produced by Dr. Crabtree have been used in experimental microsurgery with excellent results. Animal experiments have shown the tensile strength of obsidian produced wounds to be equal to or greater than that of wounds produced by steel scalpels after 14 days of healing. We have been able to demonstrate neither flaking of glass blades into the wounds nor any foreign body reaction in healed wounds. Skin incisions in human patients have likewise healed well without complications. The prismatic glass blade is infinitely sharper than a honed steel edge, and these blades can be produced in a wide variety of shapes and sizes. It is therefore suggested that this type of blade may find an appropriate use in special areas of modern surgery.

  16. Outcomes of surgery among the Medicare aged: mortality after surgery.

    PubMed

    Lubitz, J; Riley, G; Newton, M

    1985-01-01

    This study examines post-surgical mortality, up to 1 year after surgery, for eight common operations among aged Medicare enrollees. The operations with the highest mortality in the 1.5 months after surgery were femur fracture reduction, hip arthroplasty (other, i.e., not total replacement), and coronary artery bypass. Mortality was still above average for femur fracture reduction, hip arthroplasty (other), and transurethral prostatectomy 1 year after surgery. The highest mortality rates following surgery were for people 85 years of age or over. This raises the following question: Should certain elective surgery be performed at younger ages if it appears that surgery may eventually be needed?

  17. [Perspectives in glaucoma surgery].

    PubMed

    Dietlein, T S

    2002-02-01

    Trabeculectomy is still considered to be the gold standard in the surgical treatment of the open-angle glaucomas. The additional application of local antimetabolites has reduced the rate of early filtering bled fibrosis, but increased the rate of essential late-postoperative complications. Growth factor inhibition and photodynamic therapy may be an alternative local treatment to enhance the results in filtering surgery. Non-penetrating glaucoma surgery and ab-interno trabecular surgery have several conceptual advantages, e.g. the lack of overfiltration or the untouched conjunctiva in the ab-interno approach. Clinical studies of these and other new procedures including antiglaucomatous retinectomy and subchoroidal shunt systems are currently performed in order to evaluate their potential and limits in the clinical management of glaucoma.

  18. Cosmetic Facial Surgery

    PubMed Central

    Adamson, Peter A.

    1987-01-01

    Canadians have committed themselves to a healthier lifestyle, and many are seeking to look as well as they feel. For patients with realistic expectations, modern techniques of cosmetic facial surgery can enhance appearance and be of psychological benefit. Today most procedures can be done under local anesthesia on an out-patient basis. Facial contour defects can be improved by means of procedures such as rhinoplasty, mentoplasty, otoplasty and malarplasty. Facial rejuvenation surgery to decrease the signs of aging includes the forehead lift, eyebrow and eyelid lift, rhytidectomy, liposuction and chemical peeling. Newer controversial trends in cosmetic facial surgery include collagen implantation and fat transfer for contour defects, and eyelid tattooing. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:21263984

  19. Ethics in global surgery.

    PubMed

    Wall, Anji E

    2014-07-01

    Global surgery, while historically a small niche, is becoming a larger part of the global health enterprise. This article discusses the burden of global surgery, emphasizing the importance of addressing surgical needs in low- and middle-income countries. It describes the barriers to surgical care in the developing world, the ethical challenges that these barriers create, and strategies to overcome these barriers. It emphasizes the crucial role of preparation for global surgical interventions as a way to maximize benefits as well as minimize harms and ethical challenges. It ends with the cautionary statement that preparation does not eliminate ethical problems, so surgical volunteers must be prepared not only for the technical challenges of global surgery but also for the ethical challenges.

  20. [Antimicrobial prophylaxis in surgery].

    PubMed

    Cisneros, José Miguel; Rodríguez-Baño, Jesús; Mensa, José; Trilla, Antoni; Cainzos, Miguel

    2002-01-01

    Antimicrobial prophylaxis in surgery refers to a very brief course of an antimicrobial agent initiated just before the start of the procedure. The efficacy of antimicrobials to prevent postoperative infection at the site of surgery (incisional superficial, incisional deep, or organ/space infection) has been demonstrated for many surgical procedures. Nevertheless, the majority of studies centering on the quality of preoperative prophylaxis have found that a high percentage of the antimicrobials used are inappropriate for this purpose. This work discusses the scientific basis for antimicrobial prophylaxis, provides general recommendations for its correct use and specific recommendations for various types of surgery. The guidelines for surgical antimicrobial prophylaxis are based on results from well-designed studies, whenever possible. These guidelines are focussed on reducing the incidence of infection at the surgical site while minimizing the contribution of preoperative administration of antimicrobials to the development of bacterial resistance.

  1. Robotic aortic surgery.

    PubMed

    Duran, Cassidy; Kashef, Elika; El-Sayed, Hosam F; Bismuth, Jean

    2011-01-01

    Surgical robotics was first utilized to facilitate neurosurgical biopsies in 1985, and it has since found application in orthopedics, urology, gynecology, and cardiothoracic, general, and vascular surgery. Surgical assistance systems provide intelligent, versatile tools that augment the physician's ability to treat patients by eliminating hand tremor and enabling dexterous operation inside the patient's body. Surgical robotics systems have enabled surgeons to treat otherwise untreatable conditions while also reducing morbidity and error rates, shortening operative times, reducing radiation exposure, and improving overall workflow. These capabilities have begun to be realized in two important realms of aortic vascular surgery, namely, flexible robotics for exclusion of complex aortic aneurysms using branched endografts, and robot-assisted laparoscopic aortic surgery for occlusive and aneurysmal disease.

  2. Psychopharmacology and Bariatric Surgery.

    PubMed

    Roerig, James L; Steffen, Kristine

    2015-11-01

    Currently, it has been demonstrated that psychotropic drugs, particularly antidepressants, are frequently prescribed for patients who seek bariatric surgery. Many bariatric surgery patients have a history of a mood disorder. Unlike medications for diabetes, hypertension or hyperlipidemia, which are generally reduced and at times discontinued, postsurgery antidepressants use is only slightly reduced. The Roux-en-Y procedure is most frequently associated with alteration in drug exposure. Medication disintegration, dissolution, absorption, metabolism and excretion have been found to be altered in postbariatric patients, although data are sparse at this time. This paper will review the current evidence regarding the effect of bariatric surgery on drug treatment including mechanism of interference as well as the extent of changes identified to date. Data will be presented as controlled trials followed by case series and reports.

  3. Robotic Surgery for Thoracic Disease.

    PubMed

    Yamashita, Shin-Ichi; Yoshida, Yasuhiro; Iwasaki, Akinori

    2016-01-01

    Robotic surgeries have developed in the general thoracic field over the past decade, and publications on robotic surgery outcomes have accumulated. However, controversy remains about the application of robotic surgery, with a lack of well-established evidence. Robotic surgery has several advantages such as natural movement of the surgeon's hands when manipulating the robotic arms and instruments controlled by computer-assisted systems. Most studies have reported the feasibility and safety of robotic surgery based on acceptable morbidity and mortality compared to open or video-assisted thoracic surgery (VATS). Furthermore, there are accumulated data to indicate longer operation times and shorter hospital stay in robotic surgery. However, randomized controlled trials between robotic and open or VATS procedures are needed to clarify the advantage of robotic surgery. In this review, we focused the literature about robotic surgery used to treat lung cancer and mediastinal tumor.

  4. Thermomagnetic surgery for renal cancer.

    PubMed

    Rand, R W; Snow, H D; Brown, W J

    1982-01-01

    Thermomagnetic surgery is a technique that uses hysteresis heating of ferromagnetic materials to produce focally controlled temperatures within solid organs or tumors to cause coagulation necrosis. The degree of heating of a neoplasm is controlled by manipulating the power of the electromagnetic coil system through temperature monitoring. This effectively limits the region of destruction to the disease process and thereby avoids damage to surrounding structures. If the ferromagnetic material is delivered by an arterial route to the tumor or organ additional beneficial effect of ischemic necrosis of tissue may be achieved. This new technique is applicable to selected cases of human cancer. Exposure in the electromagnetic fields or use of the ferromagnetic material in experimental animals has produced no ill effects.

  5. Partially supervised speaker clustering.

    PubMed

    Tang, Hao; Chu, Stephen Mingyu; Hasegawa-Johnson, Mark; Huang, Thomas S

    2012-05-01

    Content-based multimedia indexing, retrieval, and processing as well as multimedia databases demand the structuring of the media content (image, audio, video, text, etc.), one significant goal being to associate the identity of the content to the individual segments of the signals. In this paper, we specifically address the problem of speaker clustering, the task of assigning every speech utterance in an audio stream to its speaker. We offer a complete treatment to the idea of partially supervised speaker clustering, which refers to the use of our prior knowledge of speakers in general to assist the unsupervised speaker clustering process. By means of an independent training data set, we encode the prior knowledge at the various stages of the speaker clustering pipeline via 1) learning a speaker-discriminative acoustic feature transformation, 2) learning a universal speaker prior model, and 3) learning a discriminative speaker subspace, or equivalently, a speaker-discriminative distance metric. We study the directional scattering property of the Gaussian mixture model (GMM) mean supervector representation of utterances in the high-dimensional space, and advocate exploiting this property by using the cosine distance metric instead of the euclidean distance metric for speaker clustering in the GMM mean supervector space. We propose to perform discriminant analysis based on the cosine distance metric, which leads to a novel distance metric learning algorithm—linear spherical discriminant analysis (LSDA). We show that the proposed LSDA formulation can be systematically solved within the elegant graph embedding general dimensionality reduction framework. Our speaker clustering experiments on the GALE database clearly indicate that 1) our speaker clustering methods based on the GMM mean supervector representation and vector-based distance metrics outperform traditional speaker clustering methods based on the “bag of acoustic features” representation and statistical

  6. Bariatric and metabolic surgery.

    PubMed

    Fried, M

    2013-09-01

    In the beginning of the 21st century obesity still represents health, social and economical threat for most of economically wealthy countries worldwide. Estimated direct costs for obesity and related comorbidities treatment exceed 5% of the total health care costs both in the US and in European Union. However, in addition there are obesity-related indirect costs linked to more frequent work sickness leave, higher unemployment rates and overall lower productivity of obese patients. Surgical treatment of obesity (bariatric surgery) is the most effective long-term treatment modality for those patients suffering from higher degrees of obesity. Bariatric surgery has not only positive effects on weight loss, but is also extremely effective in improving or resolving many of obesity-related comorbidities, which have evolved rapidly into the so-called metabolic surgery. T2DM may serve as excellent example of metabolic, obesity-related comorbidity which can be treated with bariatric-metabolic procedure even without direct relation to weight loss. In such cases bariatric surgery evolves into metabolic surgery. Thus metabolic operations (namely from the malabsorptive end) deeply influence hormonal secretion especially in the proximal part of small bowel, change parametres of entero-insular axis and have positive influence on insulin secretion, sensitivity and on the entire complex of glucose tolerance. Nowadays we can witness dramatic changes in perception of T2DM from bariatric surgeons, diabetologists, and many other medical specialists. T2DM has evolved from primarily medical disease into a condition where surgeons may play a more active role in the management of the diabetic patient. However, it has to be stressed that metabolic treatment of T2DM and other metabolic disorders need multidisciplinary approach and collaboration and that surgeon should play very important role as a multidisciplinary team member, however metabolic surgery should not yet be considered as stand

  7. Enzymatic vitreous surgery.

    PubMed

    Trese, M T

    2000-06-01

    Enzymatic manipulation of the vitreous and vitreoretinal juncture is currently in the process of being evaluated in many centers around the world. The goals of such manipulation are either to disinsert the posterior hyaloid from the retina surface in an atraumatic, very clean, cleavage plane or, at this point, to try to disinsert the peripheral vitreous from the neurosensory retina. In addition, enzymatic manipulation of the central vitreous in terms of liquefaction has also been evaluated. Although this is certainly the beginning of this type of vitreal surgery, adjuvant or alternative, it does appear to be a new and exciting area of vitreoretinal surgery.

  8. Avian Soft Tissue Surgery.

    PubMed

    Guzman, David Sanchez-Migallon

    2016-01-01

    Basic surgical instrumentation for avian soft tissue surgery includes soft tissue retractors, microsurgical instrumentation, surgical loupes, and head-mounted lights. Hemostasis is fundamental during the surgical procedures. The indications, approach, and complications associated with soft tissue surgeries of the integumentary (digit constriction repair, feather cyst excision, cranial wound repair, sternal wound repair, uropygial gland excision), gastrointestinal (ingluviotomy, crop biopsy, crop burn repair, celiotomy, coelomic hernia and pseudohernia repair, proventriculotomy, ventriculotomy, enterotomy, intestinal resection and anastomosis, cloacoplasty, cloacopexy), respiratory (rhinolith removal, sinusotomy, tracheotomy, tracheal resection and anastomosis, tracheostomy, pneumonectomy) and reproductive (ovocentesis, ovariectomy, salpingohysterectomy, cesarean section, orchidectomy, vasectomy, phallectomy) systems are reviewed.

  9. Robotic retroauricular thyroid surgery

    PubMed Central

    Alabbas, Haytham; Bu Ali, Daniah

    2016-01-01

    Surgery is the gold standard treatment for patients with thyroid cancer or nodules suspicious for cancer. Open conventional approach is the standard surgical approach. However, a visible neck incision could be a concern for most young female patients, especially for patients with a history of healing with keloid or hypertrophic scars. Robotic remote access approaches have evolved into a safe and feasible approach in selected patients, providing a hidden scar with good patient satisfaction. This review will focus on the performance and safety of robotic retroauricular thyroid surgery. PMID:28149806

  10. Surgery in Amphibians.

    PubMed

    Chai, Norin

    2016-01-01

    Amphibian surgery has been especially described in research. Since the last decade, interest for captive amphibians has increased, so have the indications for surgical intervention. Clinicians should not hesitate to advocate such manipulations. Amphibian surgeries have no overwhelming obstacles. These patients heal well and tolerate blood loss more than higher vertebrates. Most procedures described in reptiles (mostly lizards) can be undertaken in most amphibians if equipment can be matched to the patients' size. In general, the most difficult aspect would be the provision of adequate anesthesia.

  11. Standing equine dental surgery.

    PubMed

    Menzies, Robert A; Easley, Jack

    2014-04-01

    Dental surgeries refer to procedures that affect the dental tissues or their supporting structures. With the development of specific, efficacious, and conservative treatments, morbidity risks have been lowered and chances of benefiting the health of equids improved. Advances in quality of sedation, analgesia, and locoregional anesthesia allow a majority of dental surgeries to be performed in the standing patient. This update focuses on an orthograde endodontic technique, a minimally invasive buccotomy technique, with the potential to combine it with a transbuccal screw extraction technique, and revisits the AO pinless external fixator for fractures of the body of the mandible.

  12. Removable partial denture occlusion.

    PubMed

    Ivanhoe, John R; Plummer, Kevin D

    2004-07-01

    No single occlusal morphology, scheme, or material will successfully treat all patients. Many patients have been treated, both successfully and unsuccessfully, using widely varying theories of occlusion, choices of posterior tooth form, and restorative materials. Therefore, experience has demonstrated that there is no one righ r way to restore the occlusion of all patients. Partially edentulous patients have many and varied needs. Clinicians must understand the healthy physiologic gnathostomatic system and properly diagnose what is or may become pathologic. Henderson [3] stated that the occlusion of the successfully treated patient allows the masticating mechanism to carry out its physiologic functions while the temporomandibular joints, the neuromuscular mechanism, the teeth and their supporting structures remain in a good state of health. Skills in diagnosis and treatment planning are of utmost importance in treating these patients, for whom the clinician's goals are not only an esthetic and functional restoration but also a lasting harmonious state. Perhaps this was best state by DeVan [55] more than 60 years ago in his often-quoted objective. "The patient's fundamental need is the continued meticulous restoration of what is missing, since what is lost is in a sense irretrievably lost." Because it is clear that there is no one method, no one occlusal scheme, or one material that guarantees success for all patients, recommendations for consideration when establishing or reestablishing occlusal schemes have been presented. These recommendations must be used in conjunction with other diagnostic and technical skills.

  13. Partially solidified systems

    NASA Astrophysics Data System (ADS)

    The evolution of magmas is a topic of considerable importance in geology and geophysics because it affects volcanology, igneous petrology, geothermal energy sources, mantle convection, and the thermaland chemical evolution of the earth. The dynamics and evolution of magmas are strongly affected by the presence of solid crystals that occur either in suspension in liquid or as a rigid porous matrix through which liquid magma can percolate. Such systems are physically complex and difficult to model mathematically. Similar physical situations are encountered by metallurgists who study the solidification of molten alloys, and applied mathematicians have long been interested in such moving boundary problems. Clearly, it would be of mutual benefit to bring together scientists, engineers, and mathematicians with a common interest in such systems. Such a meeting is being organized as a North Atlantic Treaty Organization (NATO) Advanced Research Workshop on the Structure and Dynamics of Partially Solidified Systems, to be held at Stanford University's Fallen Leaf Lodge at Tahoe, Calif., May 12-16, 1986 The invited speakers and their topics are

  14. Partial disassembly of peroxisomes

    PubMed Central

    1985-01-01

    Rat liver peroxisomes were subjected to a variety of procedures intended to partially disassemble or damage them; the effects were analyzed by recentrifugation into sucrose gradients, enzyme analyses, electron microscopy, and SDS PAGE. Freezing and thawing or mild sonication released some matrix proteins and produced apparently intact peroxisomal "ghosts" with crystalloid cores and some fuzzy fibrillar content. Vigorous sonication broke open the peroxisomes but the membranes remained associated with cores and fibrillar and amorphous matrix material. The density of both ghosts and more severely damaged peroxisomes was approximately 1.23. Pyrophosphate (pH 9) treatment solubilized the fibrillar content, yielding ghosts that were empty except for cores. Some matrix proteins such as catalase and thiolase readily leak from peroxisomes. Other proteins were identified that remain in mechanically damaged peroxisomes but are neither core nor membrane proteins because they can be released by pyrophosphate treatment. These constitute a class of poorly soluble matrix proteins that appear to correspond to the fibrillar material observed morphologically. All of the peroxisomal beta-oxidation enzymes are located in the matrix, but they vary greatly in how easily they leak out. Palmitoyl coenzyme A synthetase is in the membrane, based on its co-distribution with the 22-kilodalton integral membrane polypeptide. PMID:2989301

  15. False aneurysm of aorta secondary to partial occlusion clamp injury: diagnosis by nuclear flow study

    SciTech Connect

    Becker, R.M.; Wexler, J.; Frater, R.W.

    1981-09-01

    A 72-year-old woman presented 12 months postaortic valve replacement with a false aneurysm near the aortic cannulation site. The diagnosis was suspected from clinical findings and confirmed by a nuclear flow study. The patient refused surgery and died shortly afterward. At autopsy, a smooth-walled 1 cm defect adjacent to the cannulation site (presumably related to injury from a partial occlusion clamp) was found; this would have been easily reparable with surgery.

  16. [Robotic surgery in gynecology].

    PubMed

    Hibner, Michał; Marianowski, Piotr; Szymusik, Iwona; Wielgós, Mirosław

    2012-12-01

    Introduction of robotic surgery in the first decade of the 21 century was one of the biggest breakthroughs in surgery since the introduction of anesthesia. For the first time in history the surgeon was placed remotely from the patient and was able to operate with the device that has more degrees of freedom than human hand. Initially developed for the US Military in order to allow surgeons to be removed from the battlefield, surgical robots quickly made a leap to the mainstream medicine. One of the first surgical uses for the robot was cardiac surgery but it is urology and prostate surgery that gave it a widespread popularity Gynecologic surgeons caught on very quickly and it is estimated that 31% of hysterectomies done in the United States in 2012 will be done robotically. With over half a million hysterectomies done each year in the US alone, gynecologic surgery is one of the main driving forces behind the growth of robotic surgery Other applications in gynecology include myomectomy oophorectomy and ovarian cystectomy resection of endometriosis and lymphadenectomy Advantages of the surgical robot are clearly seen in myomectomy The wrist motion allows for better more precise suturing than conventional "straight stick" laparoscopy The strength of the arms allow for better pulling of the suture and the third arm for holding the suture on tension. Other advantage of the robot is scaling of the movements when big movement on the outside translates to very fine movement on the inside. This enables much more precise surgery and may be important in the procedures like tubal anastomosis and implantation of the ureter Three-dimensional vision provides excellent depth of field perception. It is important for surgeons who are switching from open surgeries and preliminary evidence shows that it may allow for better identification of lesions like endometriosis. Another big advantage of robotics is that the surgeon sits comfortably with his/her arms and head supported. This

  17. Shifting Paradigms in Minimally Invasive Surgery: Applications of Transanal Natural Orifice Transluminal Endoscopic Surgery in Colorectal Surgery

    PubMed Central

    Lee, Grace Clara; Sylla, Patricia

    2015-01-01

    Since the advent of laparoscopy, minimally invasive techniques such as single port laparoscopy, robotics, endoscopically assisted laparoscopy, and transanal endoscopic surgery continue to revolutionize the field of colorectal surgery. Transanal natural orifice transluminal endoscopic surgery (NOTES) represents a further paradigm shift by combining the advantages of these earlier techniques to reduce the size and number of abdominal incisions and potentially optimize rectal dissection, especially with respect to performance of an oncologically adequate total mesorectal excision (TME) for rectal cancer. Since the first experimental report of transanal rectosigmoid resection in 2007, the potential impact of transanal NOTES in colorectal surgery has been extensively investigated in experimental models and recently transitioned to clinical application. There have been 14 clinical trials of transanal TME (taTME) for rectal cancer that have demonstrated the feasibility and preliminary oncologic safety of this approach in carefully selected patients, with results comparable to outcomes after laparoscopic and open TME, including cumulative intraoperative and postoperative complication rates of 5.5 and 35.5%, respectively, 97.3% rate of complete or near-complete specimens, and 93.6% rate of negative margins. Transanal NOTES has also been safely applied to proctectomy and colectomy for benign indications. The consensus among published series suggests that taTME is most safely performed with transabdominal assistance by surgeons experienced with laparoscopic TME, transanal endoscopic surgery, and sphincter-preserving techniques including intersphincteric resection. Future applications of transanal NOTES may include evolution to a pure endoscopic transanal approach for TME, colectomy, and sentinel lymph node biopsy for rectal cancer, with a potential role for robotic assistance. PMID:26491411

  18. Timing of Surgery After Spinal Cord Injury.

    PubMed

    Piazza, Matthew; Schuster, James

    2017-01-01

    Although timing for surgical intervention after spinal cord injury remains controversial, there is accumulating evidence suggesting that early surgery may improve neurologic outcomes, particularly with incomplete spinal cord injury, and may reduce non-neurologic complications and health care resource utilization. Moreover, even in patients with complete spinal cord injury, minor improvement in neurologic function can lead to significant changes in quality of life. This article reviews the experimental and clinical data examining surgical timing after spinal cord injury.

  19. [The history and development of computer assisted orthopaedic surgery].

    PubMed

    Jenny, J-Y

    2006-10-01

    Computer assisted orthopaedic surgery (CAOS) was developed to improve the accuracy of surgical procedures. It has improved dramatically over the last years, being transformed from an experimental, laboratory procedure into a routine procedure theoretically available to every orthopaedic surgeon. The first field of application of computer assistance was neurosurgery. After the application of computer guided spinal surgery, the navigation of total hip and knee joints became available. Currently, several applications for computer assisted surgery are available. At the beginning of navigation, a preoperative CT-scan or several fluoroscopic images were necessary. The imageless systems allow the surgeon to digitize patient anatomy at the beginning of surgery without any preoperative imaging. The future of CAOS remains unknown, but there is no doubt that its importance will grow in the next 10 years, and that this technology will probably modify the conventional practice of orthopaedic surgery.

  20. Robot-assisted partial adrenalectomy for isolated adrenal metastasis.

    PubMed

    Kumar, Angelish; Hyams, Elias S; Stifelman, Michael D

    2009-04-01

    Adrenal-sparing surgery is an effective and safe alternative to total adrenalectomy for small, benign adrenal lesions and may decrease the risk of the development of adrenal insufficiency. While series of laparoscopic partial adrenalectomy have demonstrated safety and excellent long-term outcomes, there have been no reports of a complete robot-assisted partial adrenalectomy. We believe that robotic techniques may be useful for this procedure, given the complex vascularity and small size of the adrenal gland. Furthermore, there have been no reports of minimally invasive partial adrenalectomy for management of small, isolated adrenal metastasis. We report a case of robot-assisted partial adrenalectomy in a patient with a history of renal-cell carcinoma who had previously undergone contralateral adrenalectomy for metastasis. We report our surgical technique and short-term follow-up for our patient. To our knowledge, this is the first report of a complete robot-assisted partial adrenalectomy and the first report of minimally invasive partial adrenalectomy for an isolated adrenal metastasis.

  1. Mitral valve surgery - open

    MedlinePlus

    ... Saunders; 2012:chap 61. Otto CM, Bonow RO. Valvular heart disease. In: Mann DL, Zipes DP, Libby P, Bonow ... Editorial team. Related MedlinePlus Health Topics Heart Surgery Heart Valve Diseases Mitral Valve Prolapse Browse the Encyclopedia A.D. ...

  2. Aortic valve surgery - open

    MedlinePlus

    ... Saunders; 2012:chap 61. Otton CM, Bowow RO. Valvular heart disease. In: Mann DL, Zipes DP, Libby P, Bonow ... Editorial team. Related MedlinePlus Health Topics Heart Surgery Heart Valve Diseases Browse the Encyclopedia A.D.A.M., Inc. ...

  3. Mohs micrographic surgery

    MedlinePlus

    ... skin/HealthProfessional . Accessed August 19, 2013. Upjohn E, Taylor RS. Mohs surgery. Rigel: Cancer of the Skin . 2nd ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 47. Review Date 12/2/2014 Updated by: Richard J. Moskowitz, MD, dermatologist in private practice, Mineola, ...

  4. Minimally invasive valve surgery.

    PubMed

    Woo, Y Joseph

    2009-08-01

    Traditional cardiac valve replacement surgery is being rapidly supplanted by innovative, minimally invasive approaches toward the repair of these valves. Patients are experiencing benefits ranging from less bleeding and pain to faster recovery and greater satisfaction. These operations are proving to be safe, highly effective, and durable, and their use will likely continue to increase and become even more widely applicable.

  5. Paediatric surgery in Uganda.

    PubMed

    Sekabira, John

    2015-02-01

    The Hugh Greenwood Lecture acknowledges the extremely generous support from Mr Greenwood that has enabled the BAPS to establish funds to advance paediatric surgical training in developing countries. In this Inaugural Lecture, Dr. Sekabira, the first Hugh Greenwood Fellow, describes the influence that this has had on his career and reviews the state of paediatric surgery in Uganda.

  6. Heart bypass surgery

    MedlinePlus Videos and Cool Tools

    Heart bypass surgery begins with an incision made in the chest, with the breastbone cut exposing the heart. Next, a portion of the saphenous vein is ... used to bypass the blocked arteries in the heart. The venous graft is sewn to the aorta ...

  7. Periscopic Spine Surgery

    DTIC Science & Technology

    2008-06-01

    modulating shoulder impedance during physical therapy 4. Demonstrated image-guided spinal vertebroplasty in a phantom model using our open source...Image-Guided Vertebroplasty ...................................... 11 3.3.3 Accomplishment 3: Abdominal Phantom Evaluation...49 7.7 Enquobahrie 2007: The image-guided surgery … .............................................. 58 7.8 Lin 2008: Phantom

  8. Anesthesia for bench surgery

    PubMed Central

    Sachin, S.; Rajesh, M. C.; Ramdas, E. K.

    2016-01-01

    Surgical removal of the kidney tumor outside the body, (ex vivo renal bench surgery) followed by auto transplantation is an emerging and often done procedure to reconstruct the urinary tract. It possesses immense challenges to both the anesthesiologists and the surgeons. The risks are multiplied if you are performing the surgery on a solitary functioning kidney. Here, we are describing the anesthetic management of 70-year-old male post nephrectomy patient undergoing renal auto transplantation by bench surgery. Our primary goals for perioperative management were to maintain a stable hemodynamics throughout the procedure, to reduce fluid overload during the period of extracorporeal surgery, to maintain perfusion for the transplanted solitary kidney, to control bleeding to a minimum, and to provide adequate analgesia for the patient. We made use of a balanced anesthetic technique and stringent monitoring standards to bring forth a successful outcome for the patient. At the end of his hospital stay, patient went home with a healthy, normally functioning kidney. PMID:27746573

  9. Decreasing strabismus surgery

    PubMed Central

    Arora, A; Williams, B; Arora, A K; McNamara, R; Yates, J; Fielder, A

    2005-01-01

    Aim: To determine whether there has been a consistent change across countries and healthcare systems in the frequency of strabismus surgery in children over the past decade. Methods: Retrospective analysis of data on all strabismus surgery performed in NHS hospitals in England and Wales, on children aged 0–16 years between 1989 and 2000, and between 1994 and 2000 in Ontario (Canada) hospitals. These were compared with published data for Scotland, 1989–2000. Results: Between 1989 and 1999–2000 the number of strabismus procedures performed on children, 0–16 years, in England decreased by 41.2% from 15 083 to 8869. Combined medial rectus recession with lateral rectus resection decreased from 5538 to 3013 (45.6%) in the same period. Bimedial recessions increased from 489 to 762, oblique tenotomies from 43 to 121, and the use of adjustable sutures from 29 to 44, in 2000. In Ontario, operations for squint decreased from 2280 to 1685 (26.1%) among 0–16 year olds between 1994 and 2000. Conclusion: The clinical impression of decrease in the frequency of paediatric strabismus surgery is confirmed. In the authors’ opinion this cannot be fully explained by a decrease in births or by the method of healthcare funding. Two factors that might have contributed are better conservative strabismus management and increased subspecialisation that has improved the quality of surgery and the need for re-operation. This finding has a significant impact upon surgical services and also on the training of ophthalmologists. PMID:15774914

  10. Cavus Foot Surgery

    MedlinePlus

    ... of the Smaller Toes How To... Foot Health Foot Injury Footwear News Videos Find a Surgeon Información en ... related problems. What are the goals of cavus foot surgery? The ... reduce other injuries such as repeated ankle sprains and broken bones. ...

  11. Hair transplantation surgery

    PubMed Central

    Khanna, Manoj

    2008-01-01

    Techniques in hair transplantation have evolved recently which make results look more natural. Hair restoration is one of the most exciting and innovative surgical fields in aesthetic surgery today. A precise appreciation of anatomy has allowed the use of follicular unit grafts. With better methods of harvesting and implantation, hair transplantation results represent a blend of art and science. PMID:20174544

  12. [Drainage in thyroid surgery].

    PubMed

    Ardito, G; Revelli, L; Guidi, M L; Murazio, M; Lucci, C; Modugno, P; Di Giovanni, V

    1999-01-01

    Bleeding represents a rare complication of thyroid surgery but when it occurs it may be life-threatening. To prevent this complication drainage is widely used. However no study has demonstrated the drains' value and recent reports have questioned its benefits. Therefore we have analyzed our experience of a 10 year-period in which 1.217 thyroidectomies were performed by the same surgical team and prophylactic routine drainage was always adopted. In 13 patients (1.06%) a benign hematoma occurred with spontaneous remission. In 6 patients the bleeding was severe and compressive hematoma occurred; it required surgical re-exploration. Such a complication is unusual in the neck surgery (0.49% in the authors' series) performed by experienced surgeons and when life-threatening hematomas do occur they depend on various uncontrolled factors and drainage is often not helpful. Otherwise a meticulous haemostatic technique is necessary and patients should be observed very closely during the few first hours following surgery on the thyroid gland. Therefore on the basis of the analysis of their series, although it is not always possible to prove the benefit of the drainage, the authors suggest its indication in the neck surgery, as in other fields with dead space, to remove blood and secretions reducing postoperative complications. They have never observed wound infections and patients were discharged within 72 hours.

  13. Intrauterine surgery in myelomeningocele.

    PubMed

    Bruner, Joseph P

    2007-12-01

    Intrauterine surgery for repair of fetal myelomeningocele has been performed since 1994. Open repair through a hysterotomy has been performed since 1997. Although much has been published about diagnosis, counseling, case selection, pre-, intra-, and postoperative management, delivery and long-term sequelae for both mother and baby, and associated ethical issues, several questions have yet to be openly discussed in a public forum.

  14. Anti-reflux surgery

    MedlinePlus

    ... much stomach acid is coming back into your esophagus). Upper endoscopy. Almost all people who have this anti-reflux surgery have already had this test. If you have not had this test, ... of the esophagus. Always tell your provider if: You could be ...

  15. Surgery with cooperative robots.

    PubMed

    Lehman, Amy C; Berg, Kyle A; Dumpert, Jason; Wood, Nathan A; Visty, Abigail Q; Rentschler, Mark E; Platt, Stephen R; Farritor, Shane M; Oleynikov, Dmitry

    2008-03-01

    Advances in endoscopic techniques for abdominal procedures continue to reduce the invasiveness of surgery. Gaining access to the peritoneal cavity through small incisions prompted the first significant shift in general surgery. The complete elimination of external incisions through natural orifice access is potentially the next step in reducing patient trauma. While minimally invasive techniques offer significant patient advantages, the procedures are surgically challenging. Robotic surgical systems are being developed that address the visualization and manipulation limitations, but many of these systems remain constrained by the entry incisions. Alternatively, miniature in vivo robots are being developed that are completely inserted into the peritoneal cavity for laparoscopic and natural orifice procedures. These robots can provide vision and task assistance without the constraints of the entry incision, and can reduce the number of incisions required for laparoscopic procedures. In this study, a series of minimally invasive animal-model surgeries were performed using multiple miniature in vivo robots in cooperation with existing laparoscopy and endoscopy tools as well as the da Vinci Surgical System. These procedures demonstrate that miniature in vivo robots can address the visualization constraints of minimally invasive surgery by providing video feedback and task assistance from arbitrary orientations within the peritoneal cavity.

  16. Trigonometric Integrals via Partial Fractions

    ERIC Educational Resources Information Center

    Chen, H.; Fulford, M.

    2005-01-01

    Parametric differentiation is used to derive the partial fractions decompositions of certain rational functions. Those decompositions enable us to integrate some new combinations of trigonometric functions.

  17. [Minilaparoscopic surgery : alternative or supplement to single-port surgery?].

    PubMed

    Brinkmann, L; Lorenz, D

    2011-05-01

    In recent years scarless surgery (axillo-bilateral-breast aproach [ABBA], natural orifice transluminal endoscopic surgery [NOTES], single-port surgery) has gained importance in order to improve postoperative outcome in laparoscopic surgery. As part of this effort minilaparoscopic surgery might be a suitable alternative concerning cosmetic outcome without implementing a completely new technique. Due to the definition minilaparoscopic surgery is based on instruments which reduce the total length of trocar incisions to less than 2.5 cm. Nevertheless the total number of incisions is similar to conventional laparoscopic techniques. Most recent indications for minilaparoscopic surgery are cholecystectomy, appendectomy, hernia and colorectal surgery. This article describes the technical aspects and feasibility of minilaparoscopic cholecystectomy and transabdominal preperitoneal hernia repair (TAPP).While the trocar positions remain in the original setting the laparoscopic surgeon benefits from experience gained in conventional laparoscopic surgery. Although the cosmetic outcome is not comparable to single-port surgery, in the author's opinion minilaparoscopic surgery is a useful alternative in scarless surgery due to the fact that it is easy to adapt without establishing a completely new technique.

  18. Does strabismus surgery improve quality and mood, and what factors influence this?

    PubMed

    McBain, H B; MacKenzie, K A; Hancox, J; Ezra, D G; Adams, G G W; Newman, S P

    2016-05-01

    AimsTo establish the impact of adult strabismus surgery on clinical and psychosocial well-being and determine who experiences the greatest benefit from surgery and how one could intervene to improve quality of life post-surgery.MethodsA longitudinal study, with measurements taken pre-surgery and at 3 and 6 months post-surgery. All participants completed the AS-20 a disease specific quality of life scale, along with measures of mood, strabismus and appearance-related beliefs and cognitions and perceived social support. Participants also underwent a full orthoptic assessment at their preoperative visit and again 3 months postoperatively. Clinical outcomes of surgery were classified as success, partial success or failure, using the largest angle of deviation, diplopia and requirement for further therapy.Results210 participants took part in the study. Strabismus surgery led to statistically significant improvements in psychosocial and functional quality of life. Those whose surgery was deemed a partial success did however experience a deterioration in quality of life. A combination of clinical variables, high expectations, and negative beliefs about the illness and appearance pre-surgery were significant predictors of change in quality of life from pre- to post-surgery.ConclusionsStrabismus surgery leads to significant improvements in quality of life up to 6 months postoperatively. There are however a group of patients who do not experience these benefits. A series of clinical and psychosocial factors have now been identified, which will enable clinicians to identify patients who may be vulnerable to poorer outcomes post-surgery and allow for the development of interventions to improve quality of life after surgery.

  19. [Aesthetic surgery, the liability].

    PubMed

    Branchet, F

    2003-10-01

    Which are the specific risks for the plastic surgeons in aesthetic surgery? There are several: first of all, patients consult by desire and not because of health problems; it is often during difficult moments in their life (job loss.). Moreover, the surgeon must give the most complete information to the patient: he must describe the surgery, the risks (even the most exceptional ones). The surgeons have to "use the best practices": what does it mean? This sentence deals with the idea that the surgeons must have all the necessary skills to perform an aesthetic surgery and to ensure the cares after the operation (experience, diploma, staff, equipment.). They do not have to guarantee a result. As they do not operate in a hurry, they must renounce to a surgery if there is a doubt concerning the risk or the result the patient is waiting for. For years we have been observing that the requests for getting compensations have been left to drift for a lot of reasons (deception with the result, youth not found again.). The capacity to discover the real reasons of an aesthetic surgery, the listening, the courage to refuse to operate if the patient expects too much. depends on the surgeon (and insurer) future quiet. Despite all these precautions, we can notice that each surgeon is involved one time in a 4-years period: he will waste his time (forensic examinations.). As a conclusion, we can say that the respect of the rules of ethics is the key to battle against the increase of files in proceedings.

  20. Anaesthesia for robotic gynaecological surgery.

    PubMed

    Gupta, K; Mehta, Y; Sarin Jolly, A; Khanna, S

    2012-07-01

    Robotic surgery is gaining widespread popularity due to advantages such as reduced blood loss, reduced postoperative pain, shorter hospital stay and better visualisation of fine structures. Robots are being used in urological, cardiac, thoracic, orthopaedic, gynaecological and general surgery. Robotic surgery received US Food and Drug Administration approval for use in gynaecological surgery in 2005. The various gynaecological robotic operations being performed are myomectomy, total and supracervical hysterectomy, ovarian cystectomy, sacral colpopexy, tubal reanastomosis, lymph node dissection, surgery of retroperitoneal ectopic pregnancy, Moskowitz procedure and endometriosis surgery. The anaesthetic considerations include difficult access to the patient intraoperatively, steep Trendelenburg position, long surgical duration and the impact of pneumoperitoneum. We highlight the complications encountered in these surgeries and methods to prevent these complications. Robotic gynaecological surgery can be safely performed after considering the physiological effects of the steep Trendelenburg position and of pneumoperitoneum. The benefits of the surgical procedure should be weighed against the risks in patients with underlying cardiorespiratory problems.

  1. Infant open heart surgery (image)

    MedlinePlus

    During open-heart surgery an incision is made through the breastbone (sternum) while the child is under general anesthesia. ... During open-heart surgery an incision is made through the breastbone (sternum) while the child is under general anesthesia.

  2. Ostomy Surgery of the Bowel

    MedlinePlus

    ... about when they can resume normal activities. Maintaining Personal Relationships after Ostomy Surgery People with an ostomy should be able to maintain personal relationships just as before their surgery. Some people ...

  3. Using your shoulder after surgery

    MedlinePlus

    ... medlineplus.gov/ency/patientinstructions/000175.htm Using your shoulder after surgery To use the sharing features on ... please enable JavaScript. You had surgery on your shoulder to repair a muscle, tendon, or cartilage tear. ...

  4. What Happens After Heart Surgery?

    MedlinePlus

    ANSWERS by heart Treatments + Tests What Happens After Heart Surgery? What are the ICU and CCU? In a ... doctors. This is where patients go after open-heart surgery or a heart attack. You’re watched around ...

  5. Pediatric cardiac surgery with echocardiographic diagnosis alone.

    PubMed Central

    Sohn, Sejung; Kim, Hae Soon; Han, Jae Jin

    2002-01-01

    The diagnostic accuracy of echocardiography alone and the safety of cardiac surgery using this diagnostic approach were retrospectively assessed in 111 children operated for congenital heart defects (CHD) during a 3.5-yr period ending in October 2001. Preoperative diagnosis was compared with the intraoperative findings obtained by surgical inspection. Perioperative death was defined as death within 30 days postoperatively. Of the patients, 70% were operated on in infancy. Seventy-six percent (84 of 111) underwent surgery after echocardiographic diagnosis alone. A high percentage of patients with patent ductus arteriosus (100%), partial atrioventricular canal (100%), coarctation of the aorta (89%), ventricular septal defect (86%), atrial septal defect (85%), and total anomalous pulmonary venous connection (75%) was operated without prior catheterization. Diagnostic errors occurred in 2.4% (2 of 84) of patients with echocardiography only and in 7.4% of patients with catheterization. No error in either group was related to surgical morbidity or mortality. There were five (6.0%) perioperative deaths in the echocardiography group and two (7.4%) in the catheterization group, with no difference in the mortality between the groups. In conclusion, many patients with CHD can be accurately diagnosed by echocardiography alone, and can safely undergo surgery without catheterization, not increasing the overall risk. PMID:12172039

  6. Future applications of lasers in surgery and medicine: a review.

    PubMed Central

    Sliney, D H; Wolbarsht, M L

    1989-01-01

    The experimental use of lasers in surgery and medicine began only shortly after the development of the first working laser system. However, the development of practical, effective, and safe surgical lasers has been lengthy with many obstacles and delays. Today the laser is used for a wide variety of surgical operations. The fundamental limits and potential for future applications of lasers in surgery and medicine are discussed. PMID:2666663

  7. Ocular safety limits for 1030nm femtosecond laser cataract surgery

    NASA Astrophysics Data System (ADS)

    Wang, Jenny; Sramek, Christopher; Paulus, Yannis M.; Lavinsky, Daniel; Schuele, Georg; Anderson, Dan; Dewey, David; Palanker, Daniel V.

    2013-03-01

    Application of femtosecond lasers to cataract surgery has added unprecedented precision and reproducibility but ocular safety limits for the procedure are not well-quantified. We present an analysis of safety during laser cataract surgery considering scanned patterns, reduced blood perfusion, and light scattering on residual bubbles formed during laser cutting. Experimental results for continuous-wave 1030 nm irradiation of the retina in rabbits are used to calibrate damage threshold temperatures and perfusion rate for our computational model of ocular heating. Using conservative estimates for each safety factor, we compute the limits of the laser settings for cataract surgery that optimize procedure speed within the limits of retinal safety.

  8. Robotics and telemanipulation technologies for endoscopic surgery. A review of the ARTEMIS project. Advanced Robotic Telemanipulator for Minimally Invasive Surgery.

    PubMed

    Schurr, M O; Buess, G; Neisius, B; Voges, U

    2000-04-01

    In endoscopic surgery, the ability to guide the instrument is significantly decreased compared with open surgery. Rigid laparoscopic instruments offer only four of the six degrees of freedom required for the free handling of objects in space. Robotics technology can be used to restore full mobility of the endoscopic instrument. Therefore, we designed a master-slave manipulator system (ARTEMIS) for laparoscopic surgery as a prototype. The system consists of two robotic arms holding two steerable laparoscopic instruments. These two work units are controlled from a console equipped with two master arms operated by the surgeon. The systems and its components were evaluated experimentally. Laparoscopic manipulations were feasible with the ARTEMIS system. The placement of ligatures and sutures and the handling of catheters were possible in phantom models. The surgical practicability of the system was demonstrated in animal experiments. We conclude that robotic manipulators are feasible for experimental endoscopic surgery. Their clinical application requires further technical development.

  9. Exocyclic push-pull conjugated compounds. Part 3. An experimental NMR and theoretical MO ab initio study of the structure, the electronic properties and barriers to rotation about the exocyclic partial double bond in 2- exo-methylene- and 2-cyanoimino-quinazolines and -benzodiazepines

    NASA Astrophysics Data System (ADS)

    Benassi, R.; Bertarini, C.; Hilfert, L.; Kempter, G.; Kleinpeter, E.; Spindler, J.; Taddei, F.; Thomas, S.

    2000-03-01

    The structure of a number of 2- exo-methylene substituted quinazolines and benzodiazepines, respectively, 1, 3a, b, 4( X=-CN, -COOEt ) and their 2-cyanoimino substituted analogues 2, 3c, d( X=-CN, -SO 2C 6H 4-Me (p) was completely assigned by the whole arsenal of 1D and 2D NMR spectroscopic methods. The E/ Z isomerism at the exo-cyclic double bond was determined by both NMR spectroscopy and confirmed by ab initio quantum chemical calculations; the Z isomer is the preferred one, its amount proved dependent on steric hindrance. Due to the push-pull effect in this part of the molecules the restricted rotation about the partial C 2,C 11 and C 2,N 11 double bonds, could also be studied and the barrier to rotation measured by dynamic NMR spectroscopy. The free energies of activation of this dynamic process proved very similar along the compounds studied but being dependent on the polarity of the solvent. Quantum chemical calculations at the ab initio level were employed to prove the stereochemistry at the exo-cyclic partial double bonds of 1- 4, to calculate the barriers to rotation but also to discuss in detail both the ground and the transition state of the latter dynamic process in order to better understand electronic, inter- and intramolecular effects on the barrier to rotation which could be determined experimentally. In the cyanoimino substituted compounds 2, 3c, d, the MO ab initio calculations evidence the isomer interconversion to be better described by the internal rotation process than by the lateral shift mechanism.

  10. Virtual Mentor Cataract Surgery Trainer

    DTIC Science & Technology

    2009-09-01

    AD_________________ AWARD NUMBER: W81XWH-08-1-0531 TITLE: Virtual Mentor Cataract Surgery Trainer...REPORT TYPE Annual 3. DATES COVERED 20 Aug 2008 – 19 Aug 2009 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Virtual Mentor Cataract Surgery ...Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT The Virtual Mentor Cataract Surgery Trainer is a computer based, cognitive

  11. Resistance to extinction after schedules of partial delay or partial reinforcement in rats with hippocampal lesions.

    PubMed

    Rawlins, J N; Feldon, J; Ursin, H; Gray, J A

    1985-01-01

    Two experimental procedures were employed to establish the reason why hippocampal lesions apparently block the development of tolerance for aversive events in partial reinforcement experiments, but do not do so in partial punishment experiments. Rats were trained to run in a straight alley following hippocampal lesions (HC), cortical control lesions (CC) or sham operations (SO), and resistance to extinction was assessed following differing acquisition conditions. In Experiment 1 a 4-8 min inter-trial interval (ITI) was used. Either every acquisition trial was rewarded immediately (Continuous Reinforcement, CR), or only a randomly selected half of the trials were immediately rewarded, the reward being delayed for thirty seconds on the other trials (Partial Delay, PD). This delay procedure produced increased resistance to extinction in rats in all lesion groups. In Experiment 2 the ITI was reduced to a few seconds, and rats were trained either on a CR schedule, or on a schedule in which only half the trials were rewarded (Partial Reinforcement, PR). This form of partial reinforcement procedure also produced increased resistance to extinction in rats in all lesion groups. It thus appears that hippocampal lesions only prevent the development of resistance to aversive events when the interval between aversive and subsequent appetitive events exceeds some minimum value.

  12. Fraunhofer diffraction of a partially blocked spiral phase plate.

    PubMed

    Cottrell, Don M; Davis, Jeffrey A; Hernandez, Travis J

    2011-07-04

    The Fraunhofer diffraction pattern from a partially blocked spiral phase plate (SPP) produces a partial vortex output pattern that is rotated by 90 degrees compared with the input. The rotation direction depends on whether the angular phase pattern increases in the clockwise or counterclockwise direction. In this work, we present an explanation of this effect based on careful examination of classical diffraction theory and show new experimental results. This approach is very convenient for easily determining the sign of the vortex charge.

  13. The day of your surgery - adult

    MedlinePlus

    Same-day surgery - adult; Ambulatory surgery - adult; Surgical procedure - adult; Preoperative care - day of surgery ... meet with them at an appointment before the day of surgery or on the same day of ...

  14. The day of surgery for your child

    MedlinePlus

    Same-day surgery - child; Ambulatory surgery - child; Surgical procedure - child ... The anesthesia and surgery team will talk with you and your child before surgery. You may meet with them at an appointment before ...

  15. Bariatric Surgery and the Endocrine System

    MedlinePlus

    ... Bariatric Surgery and the Endocrine System Fact Sheet Bariatric Surgery and the Endocrine System February, 2012 Download PDFs ... John Morton, MD Marzieh Salehi, MD What is bariatric surgery? Bariatric surgery helps people who are very obese ...

  16. Minimizing fire risk during eye surgery.

    PubMed

    Ho, Sin-Yee; French, Peter

    2002-11-01

    Supplemental oxygen under the drapes in high concentrations can lead to fires in ophthalmic theaters. This study attempted to eliminate the fire risk while maintaining the required therapeutic effect. The sample consisted of 201 patients undergoing ophthalmic surgery, with 104 subjects in the control group and 97 in the experimental group. A quasi-experimental design compared the existing method of oxygen administration (100% supply) with a new method (experimental) providing 24% oxygen supply. Measurements of the oxygen concentration were taken along with the fractional inspiratory carbon dioxide (FiCO2), the peripheral oxygen saturation (SpO2), the end tidal carbon dioxide (ETCO2), and the respiratory rate (RR). There was a significant difference in oxygen and carbon dioxide concentrations under the drapes (p <.05). The fractional inspiratory carbon dioxide was reduced in the experimental group. The new method was adopted to reduce the risk of fire in ophthalmic operating theaters.

  17. Activated partial thromboplastin time of owl monkey (Aotus trivirgatus) plasma.

    PubMed

    Mrema, J E; Johnson, G S; Kelley, S T; Green, T J

    1984-06-01

    Owl monkey plasma samples produced short, reproducible activated partial thromboplastin times, similar to those obtained with samples from many other mammalian species. This was an apparent contradiction to an earlier report of long irreproducible activated partial thromboplastin times from owl monkey samples. The discrepant data could not be explained by differences in anticoagulants (citrate or oxalate), assay reagents (partial thromboplastin with either diatomaceous earth or ellagic acid), or activation incubation times (2, 5, or 10 minutes); nor could they be explained by differences in the monkeys' sex, age or previous experimental exposure to Plasmodium falciparum malaria.

  18. Cataract Surgery Tool

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The NASA-McGannon cataract surgery tool is a tiny cutter-pump which liquefies and pumps the cataract lens material from the eye. Inserted through a small incision in the cornea, the tool can be used on the hardest cataract lens. The cutter is driven by a turbine which operates at about 200,000 revolutions per minute. Incorporated in the mechanism are two passages for saline solutions, one to maintain constant pressure within the eye, the other for removal of the fragmented lens material and fluids. Three years of effort have produced a design, now being clinically evaluated, with excellent potential for improved cataract surgery. The use of this tool is expected to reduce the patient's hospital stay and recovery period significantly.

  19. Simulation in laparoscopic surgery.

    PubMed

    León Ferrufino, Felipe; Varas Cohen, Julián; Buckel Schaffner, Erwin; Crovari Eulufi, Fernando; Pimentel Müller, Fernando; Martínez Castillo, Jorge; Jarufe Cassis, Nicolás; Boza Wilson, Camilo

    2015-01-01

    Nowadays surgical trainees are faced with a more reduced surgical practice, due to legal limitations and work hourly constraints. Also, currently surgeons are expected to dominate more complex techniques such as laparoscopy. Simulation emerges as a complementary learning tool in laparoscopic surgery, by training in a safe, controlled and standardized environment, without jeopardizing patient' safety. Simulation' objective is that the skills acquired should be transferred to the operating room, allowing reduction of learning curves. The use of simulation has increased worldwide, becoming an important tool in different surgical residency programs and laparoscopic training courses. For several countries, the approval of these training courses are a prerequisite for the acquisition of surgeon title certifications. This article reviews the most important aspects of simulation in laparoscopic surgery, including the most used simulators and training programs, as well as the learning methodologies and the different key ways to assess learning in simulation.

  20. Hand transplant surgery.

    PubMed

    Nassimizadeh, M; Nassimizadeh, A K; Power, D

    2014-11-01

    In September 1998 the world's first hand transplant was performed in Lyon, France. A new era in reconstructive surgery had begun. This case highlighted the potential for composite tissue allotransplantation (CTA). While CTA is not a new technique, it unifies the principles of reconstructive microsurgery and transplant surgery, achieving the goals of absolute correction of a defect with anatomically and physiologically identical tissue with none of the issues of donor site morbidity associated with autologous tissue transfer. The adoption of this technique for non-life threatening conditions to improve quality of life has generated a number of new ethical considerations. Additionally, the prominence of transplanted hands has led to much discussion around the issue of body identity and psychological assessment of potential recipients. This is fundamental to any hand transplantation programme. With the advent of hand transplantation dawning in the UK, we review the many ethical considerations that contribute to this new frontier.

  1. Transoral Robotic Surgery.

    PubMed

    Yee, Shokjean

    2017-01-01

    Transoral robotic surgery (TORS) is a technique used to treat oral, throat, and skull base cancers using a minimally invasive robotic approach through the mouth and throat. The TORS procedure allows deeper access and dissection of suspicious lesions and neoplastic growths in the oral cavity and those that extend from the throat to the base of the skull. Robotic surgery allows the surgeon to operate in tight spaces without a large open incision. This article discusses symptoms and risk factors of oral, throat, and skull base cancers; types of procedures that can be performed using the TORS approach; specialized instrumentation; patient selection; surgical advantages and disadvantages; patient benefits; and the role of the surgical team in preparing to intraoperatively care for the TORS patient.

  2. Laser and Surgery

    NASA Astrophysics Data System (ADS)

    Casaccia, Mario; Campisi, C.; Pasero, E.; Ieracitano, V. M.; Berardi, L.; Padula, P.; Cordaro, S.; Boccardo, F.

    1990-09-01

    Surgeon's hand, guiding a light ray, Laser, instead of holding a common lancet, for dissecting delicately tissues with simultaneous haemostasis on small vessels, represents one of the most interesting expressions of modern technology applied to surgery. The use of Laser in surgery dates back to 25 years ago. Its medical applications, however, are a little more recent. The word Laser comes from "Light Amplification by Stimulated Emission of Radiation". It " is known that any material, which has been stimulated, emits energy of excitation through the so called spontaneous Energy. This means irradiation of "quanta" of electro-magnetic energy untidily in space and time (so called "incoherent Emission"). A Laser source, conversely, emits "coherent" electro-magnetic radiations (so called "stimulated Emission") , whose characteristics consist in: monochromaticity,directional ity, coherence and brilliance.

  3. Hand transplant surgery

    PubMed Central

    Nassimizadeh, AK; Power, D

    2014-01-01

    In September 1998 the world’s first hand transplant was performed in Lyon, France. A new era in reconstructive surgery had begun. This case highlighted the potential for composite tissue allotransplantation (CTA). While CTA is not a new technique, it unifies the principles of reconstructive microsurgery and transplant surgery, achieving the goals of absolute correction of a defect with anatomically and physiologically identical tissue with none of the issues of donor site morbidity associated with autologous tissue transfer. The adoption of this technique for non-life threatening conditions to improve quality of life has generated a number of new ethical considerations. Additionally, the prominence of transplanted hands has led to much discussion around the issue of body identity and psychological assessment of potential recipients. This is fundamental to any hand transplantation programme. With the advent of hand transplantation dawning in the UK, we review the many ethical considerations that contribute to this new frontier. PMID:25350176

  4. [Cosmetic eyelid surgery].

    PubMed

    Ruban, J-M; Barbier, J; Malet, T; Baggio, E

    2014-01-01

    Cosmetic eyelid surgery is becoming increasingly popular. It can rejuvenate the patient's appearance with relatively minor side effects. Its risk/benefit ratio is one of the best in facial cosmetic surgery. However, the patient does not always accurately assess the aesthetic appearance of his or her eyelids. This underscores the importance of clinical examination in order to determine the patient's wishes, and then make an accurate diagnosis and potential surgical plan. We currently oppose, in general, surgical techniques involving tissue removal (skin-muscle and/or fat) in favor of those involving tissue repositioning and grafting (autologous fat pearl transposition, obtained by liposuction, and lipostructure). Furthermore, the place of adjuvant therapies to blepharoplasty is steadily increasing. They mainly include surface treatments (peels and lasers), dermal fillers and anti-wrinkle botulinum toxin injections. They are also increasingly used in isolation in novel ways. In all cases, a perfect knowledge of anatomy and relevant skills and experience remain necessary.

  5. Lasers in oral surgery

    NASA Astrophysics Data System (ADS)

    Keller, Ulrich; Hibst, Raimund

    1994-12-01

    The indications of lasers in oral surgery are defined by the laser-tissue interaction types. These are mainly thermal effects depending especially on the absorption of laser light in varying biological tissues. In histological sections different laser effects are demonstrated on oral mucosa, bone and cartilage, which have a great influence on wound healing and subsequently on clinical indications of the different wavelengths. On the one hand the good coagulation effect of the Nd:YAG laser is wanted for hemostasis in soft tissue surgery. On the other hand, for the treatment of precancerous dysplasias or neoplasias an effective cutting with a coagulation effect like using the CO2 laser is necessary. However, the excision of benign mucosal lesions as well as performing osteotomies or shaping of cartilage should be undertaken with the Er:YAG laser without greater coagulation and consequently without any delay of wound healing.

  6. Minor surgery in microgravity

    NASA Technical Reports Server (NTRS)

    Billica, Roger; Krupa, Debra T.; Stonestreet, Robert; Kizzee, Victor D.

    1991-01-01

    The purpose is to investigate and demonstrate equipment and techniques proposed for minor surgery on Space Station Freedom (SSF). The objectives are: (1) to test and evaluate methods of surgical instrument packaging and deployment; (2) to test and evaluate methods of surgical site preparation and draping; (3) to evaluate techniques of sterile procedure and maintaining sterile field; (4) to evaluate methods of trash management during medical/surgical procedures; and (4) to gain experience in techniques for performing surgery in microgravity. A KC-135 parabolic flight test was performed on March 30, 1990 with the goal of investigating and demonstrating surgical equipment and techniques under consideration for use on SSF. The flight followed the standard 40 parabola profile with 20 to 25 seconds of near-zero gravity in each parabola.

  7. Computer-guided surgery in implantology: review of basic concepts.

    PubMed

    de Almeida, Erika Oliveira; Pellizzer, Eduardo Piza; Goiatto, Marcelo Coelho; Margonar, Rogério; Rocha, Eduardo Passos; Freitas, Amilcar Chagas; Anchieta, Rodolfo Bruniera

    2010-11-01

    The aim of the present study was to conduct a critical literature review about the technique of computer-guided surgery in implantology to highlight the indications, purposes, immediate loading of implants and complications, protocol of fabrication, and functioning of virtual planning software. This literature review was based on OLDMEDLINE and MEDLINE databases from 2002 to 2010 using the key words "computer-guided surgery" and "implant-supported prosthesis." Thirty-four studies regarding this topic were found. According to the literature review, it was concluded that the computer-assisted surgery is an excellent treatment alternative for patients with appropriate bone quantity for implant insertion in complete and partially edentulous arches. The Procera Nobel Guide software (Nobel Biocare) was the most common software used by the authors. In addition, the flapless surgery is advantageous for positioning of implants but with accurate indication. Although the computer-guided surgery may be helpful for virtual planning of cases with severe bone resorption, the conventional surgical technique is more appropriate. The surgical guide is important for insertion of the implants regardless of the surgical technique, and the success of immediate loading after computer-guided surgery depends on the accuracy of clinical and/or laboratorial steps.

  8. Safe Surgery Trainer

    DTIC Science & Technology

    2015-08-15

    Norfolk (or other) by UCF research partners, in August for 2nd study. 9) Related Activities a) Submitting SST to the I/ITSEC Serious Games Challenge...of Games , Communication, and Innovation.” Abstract was accepted. Final paper was denied. d) Presented talk at the International Modelling and...Simulation in Healthcare (IMSH) 2015 conference, New Orleans, Louisiana, Jan 10-14, 2015. “Safer Surgery with Games – The Moment of Truth” e

  9. [Laparoscopic surgery: planning program].

    PubMed

    Sarli, L; Pietra, N; Carreras, F; Longinotti, E

    1992-01-01

    Performing laparoscopic surgery requires an initial training program. A well-planned organization is essential and the surgeon has to become first familiar with the new procedures; the choice of the necessary equipment is the second step. Upkeep of surgical instruments and a careful consideration of legal aspects are the next important steps. Several areas of a planning program are evaluated on the basis of the authors' experience.

  10. Laparoscopy in General Surgery

    PubMed Central

    O'Regan, Patrick J.; Anderson, Dawn L.

    1992-01-01

    After a period of rather slow initial acceptance by general surgeons, laparoscopy and video endoscopic surgery have suddenly burst on to the surgical scene. Almost overnight many of the surgical procedures once requiring a large incision are now being performed through small punctures. This article describes some of the more common procedures and discusses the merits and difficulties associated with these innovations. ImagesFigure 1Figure 2Figure 3Figure 4 PMID:21221367

  11. Pediatric Sleep Surgery

    PubMed Central

    Sulman, Cecille G.

    2014-01-01

    Adenotonsillectomy is the most common surgery performed for sleep disordered breathing with good outcomes. Children with obesity, craniofacial disorders, and neurologic impairment are at risk for persistent sleep apnea after adenotonsillectomy. Techniques exist to address obstructive lesions of the palate, tongue base, or craniofacial skeleton in children with persistent sleep apnea. Children with obstructive sleep apnea have a higher rate of peri-operative complications. PMID:24926473

  12. [Conservative surgery of splenic trauma in children].

    PubMed

    Abrantes, W L; de Lucena, M S; Schlobach, M C

    1994-01-01

    The spleen is an important component of the immunologic system, especially in children. Splenectomy may result in immunologic deficiency, and splenic salvage is recommended as management in splenic surgery. PURPOSE--Splenic injury management, considering splenic salvage as a safe therapeutic option in these children. METHODS--One hundred and thirty nine (139) children, aged 5 months to 12 years were at João XXIII Hospital, Belo Horizonte, Brazil, for the period of 1981 to 1990. The causes of the trauma, the extent and the management of splenic injuries were evaluated. Hemodynamic instability with shock occurred in 30% of the children. The contusions were responsible for injury in 135 patients (97.2%) with 58.7% caused by pedestrian/motor vehicle accidents 41.6% of splenic injury were grade I and II, 30.6% were grade III, and 26.5 grade IV e V (Injury Scalling Committee). RESULTS--Non operative management was done in 2 patients and 137 were operated on. Conservative surgery was performed in 98 patients (71.5%), which included: splenorraphy in 81 (82.6); partial splenectomy in 10 (10.2%), and laparotomy followed by observation in 7 (7.1%). Post-surgical hemorrhage occurred in one case after conservative surgery. Splenectomy was performed in 39 (28.5%) of the patients with 75-100% of the splenic injury classified in grades IV and V. Multiple associated lesions occurred in 87 children (62.5%). The mortality rate was 10.5%. Cranioencephalic trauma was the cause of death in 13 children. CONCLUSION--The splenic salvage is a possible option in the management of splenic injury in 70% of the cases. Nonoperative treatment of splenic injury depends on the physiologic status of the patient, CT scan demonstration of splenic injury and intensive care management. If there was an associated abdominal injury, there would be an indication for surgery.

  13. [Bariatric surgery: an update].

    PubMed

    Moreno Esteban, B; Zugasti Murillo, A

    2004-01-01

    The indication of bariatric surgery as therapeutic procedure for morbid obese patients requires the application of selection criteria which deal with the degree of obesity, associated complications and previous failure of conventional therapy. Alcohol or drug addiction and concomitant serious disease are contraindications for bariatric surgery. Before operation, a full assessment is needed to identify possible eating behaviour disturbances and associated comorbidity such as cardiovascular disease, sleep apnoea, metabolic and psychiatric alterations which might induce intra and postoperative complications. Surgical techniques can be classified as restrictive, malabsortive and mixed procedures. Gastroplasty and adjustable gastric banding are restrictive techniques, which are indicated in obese patients with body mass index less than 45 kg/m2. Mixed techniques are the most used procedures. They include gastric by-pass which causes a reduction of 60-70% of weight excess, biliopancreatic diversion and duodenal switch which can eliminate a 75% of body weight excess. Following bariatric surgery a dramatic improvement in associated comorbidity can be demonstrated, specially in what refers to diabetes, hypertension, dislipidaemia and apnoea. Postoperative mortality is around 1-2%. Peritonitis and venous thromboembolism are the most serious complications. Postoperative follow-up should be lifelong and requires a progressive nutrition planning and vitamin supplementation.

  14. Radioguided Adrenal Surgery

    PubMed Central

    Deus, Javier; Millera, Alfonso; Andrés, Alejandro; Prats, Enrique; Gil, Ismael; Suarez, Manuel; Salcini, José L.; Lahoz, Manuel

    2015-01-01

    Abstract The laparoscopic adrenalectomy is considered as the procedure of choice for the treatment of adrenal hyperplasia and tumor lesions. However, some special situations may limit the use of this method due to the difficulty to locate the gland and perform the lesion excision. We analyze 2 patients of a left adrenal tumor, explaining how they have overcome the difficulties in both situations. The first case was a patient with a history of intra-abdominal surgery and the other patient suffered from severe obesity. We performed with the use of the gamma probe, and the 2 cases, was of great help to access and glandular localization. The help of gamma probe test was achieved in the surgical bed, that removal was complete. The use of the portable gamma probe facilitated the access to the left adrenal gland as well as conducting the glandular excision without delay, despite the difficulties due to the intra abdominal surgery caused by the previous surgery, and in the case of severe obesity. PMID:26426608

  15. Robotic Surgery in Gynecology

    PubMed Central

    Bouquet de Joliniere, Jean; Librino, Armando; Dubuisson, Jean-Bernard; Khomsi, Fathi; Ben Ali, Nordine; Fadhlaoui, Anis; Ayoubi, J. M.; Feki, Anis

    2016-01-01

    Minimally invasive surgery (MIS) can be considered as the greatest surgical innovation over the past 30 years. It revolutionized surgical practice with well-proven advantages over traditional open surgery: reduced surgical trauma and incision-related complications, such as surgical-site infections, postoperative pain and hernia, reduced hospital stay, and improved cosmetic outcome. Nonetheless, proficiency in MIS can be technically challenging as conventional laparoscopy is associated with several limitations as the two-dimensional (2D) monitor reduction in-depth perception, camera instability, limited range of motion, and steep learning curves. The surgeon has a low force feedback, which allows simple gestures, respect for tissues, and more effective treatment of complications. Since the 1980s, several computer sciences and robotics projects have been set up to overcome the difficulties encountered with conventional laparoscopy, to augment the surgeon’s skills, achieve accuracy and high precision during complex surgery, and facilitate widespread of MIS. Surgical instruments are guided by haptic interfaces that replicate and filter hand movements. Robotically assisted technology offers advantages that include improved three-dimensional stereoscopic vision, wristed instruments that improve dexterity, and tremor canceling software that improves surgical precision. PMID:27200358

  16. Art and epilepsy surgery.

    PubMed

    Ladino, Lady Diana; Hunter, Gary; Téllez-Zenteno, José Francisco

    2013-10-01

    The impact of health and disease has led many artists to depict these themes for thousands of years. Specifically, epilepsy has been the subject of many famous works, likely because of the dramatic and misunderstood nature of the clinical presentation. It often evokes religious and even mythical processes. Epilepsy surgical treatment has revolutionized the care of selected patients and is a relatively recent advance. Epilepsy surgery has been depicted in very few artistic works. The first portrait showing a potential surgical treatment for patients with epilepsy was painted in the 12th century. During the Renaissance, Bosch famously provided artistic commentary on traditional beliefs in "The stone of madness". Several of these works demonstrate a surgeon extracting a stone from a patient's head, at one time believed to be the source of all "folly", including epileptic seizures, psychosis, intellectual disability, depression, and a variety of other illnesses. There are some contemporary art pieces including themes around epilepsy surgery, all of them depicting ancient Inca Empire procedures such as trepanning. This article reviews the most relevant artistic works related with epilepsy surgery and also its historical context at the time the work was produced. We also present a painting from the Mexican artist Eduardo Urbano Merino that represents the patient's journey through refractory epilepsy, investigations, and ultimately recovery. Through this work, the artist intends to communicate hope and reassurance to patients going through this difficult process.

  17. Percutaneous Nephroscopic Surgery

    PubMed Central

    2010-01-01

    With the development of techniques for percutaneous access and equipment to disintegrate calculi, percutaneous nephroscopic surgery is currently used by many urologists and is the procedure of choice for the removal of large renal calculi and the management of diverticula, intrarenal strictures, and urothelial cancer. Although it is more invasive than shock wave lithotripsy and retrograde ureteroscopic surgery, percutaneous nephroscopic surgery has been successfully performed with high efficiency and low morbidity in difficult renal anatomies and patient conditions. These advantages of minimal invasiveness were rapidly perceived and applied to the management of ureteropelvic junction obstruction, calyceal diverticulum, infundibular stenosis, and urothelial cancer. The basic principle of endopyelotomy is a full-thickness incision of the narrow segment followed by prolonged stenting and drainage to allow regeneration of an adequate caliber ureter. The preferred technique for a calyceal diverticulum continues to be debated. Excellent long-term success has been reported with percutaneous, ureteroscopic, and laparoscopic techniques. Each approach is based on the location and size of the diverticulum. So far, percutaneous ablation of the calyceal diverticulum is the most established minimally invasive technique. Infundibular stenosis is an acquired condition usually associated with inflammation or stones. Reported series of percutaneously treated infundibular stenosis are few. In contrast with a calyceal diverticulum, infundibular stenosis is a more difficult entity to treat with only a 50-76% success rate by percutaneous techniques. Currently, percutaneous nephroscopic resection of transitional cell carcinoma in the renal calyx can be applied in indicated cases. PMID:20495691

  18. Radiation of partially ionized atomic hydrogen

    NASA Technical Reports Server (NTRS)

    Soon, W. H.; Kunc, J. A.

    1990-01-01

    A nonlinear collisional-radiative model for determination of production of electrons, positive and negative ions, excited atoms, and spectral and continuum line intensities in stationary partially ionized atomic hydrogen is presented. Transport of radiation is included by coupling the rate equations for production of the electrons, ions, and excited atoms with the radiation escape factors, which are not constant but depend on plasma conditions. It is found that the contribution of the negative ion emission to the total continuum emission can be important. Comparison of the calculated total continuum emission coefficient, including the negative ion emission, is in good agreement with experimental results.

  19. Over surgery in breast cancer.

    PubMed

    MacNeill, Fiona; Karakatsanis, Andreas

    2017-02-01

    Breast surgery remains the original and most effective 'targeted' therapy: excision of early cancer is curative and for more advanced disease surgery improves local disease control. However in well intentioned pursuit of cure and local disease control, some cancers are over-treated resulting in major physical and emotional morbidity. Less breast surgery is safe, as evidenced by steady reductions in mortality and local recurrence; earlier diagnosis and widespread use of systemic therapies and radiotherapy have allowed more conservative surgery. As tumour biology dictates cancer outcomes not surgery extent, surgery can safely be 'minimum required' rather than 'more is better' with the focus on removal of disease rather than healthy tissue. Surgeons can reduce the burden of surgery further but it is important that less surgery is not over-compensated by more radical or unnecessary systemic therapies and/or radiotherapy with their own toxicities and morbidity. We all need to be alert to the potential drivers of over treatment and over surgery such as failure to work within a multidisciplinary team, failure to design a multimodality treatment plan at diagnosis or overuse of novel assessment technologies of uncertain clinical utility. Pursuit of wide margins and the removal of the contra-lateral healthy breast for marginal risk-reduction gains are also to be discouraged as is routine local/regional surgery in stage 4 disease. The surgeon has a pivotal role in minimizing breast surgery to what is required to achieve the best oncological, functional and aesthetic outcomes.

  20. Corneoplastique™: Art of vision surgery

    PubMed Central

    Gulani, Arun C

    2014-01-01

    Corneoplastique incorporates the entire spectrum of Vision corrective surgery including Lasik, premium cataract surgery, corneal surgery, ocular surface surgery and the full range of anterior segment surgery itself in manipulating the optics of every eye towards unaided emmetropia to define each and every eye surgeon as a “Vision Corrective Surgeon”. This concept of approaching each case individually and designing vision therewith enables surgeons to correct not only virgin eyes but also approach complex cases and complications with the goal of 20/20 vision. Armed with this holistic approach, eye surgeons can use minimally invasive, aesthetically pleasing and visually focused surgery in single or staged process aiming for each patient's Best Vision Potential (BVP) raising eye surgery itself then to an Art! PMID:24492495

  1. Total and Partial Laser Arytenoidectomy for Bilateral Vocal Fold Paralysis.

    PubMed

    Yılmaz, Taner; Altuntaş, Ozan Muzaffer; Süslü, Nilda; Atay, Gamze; Özer, Serdar; Kuşçu, Oğuz; Sözen, Tevfik

    2016-01-01

    Introduction. Treatment for bilateral vocal fold paralysis (BVFP) has evolved from external irreversible procedures to endolaryngeal laser surgery with greater focus on anatomic and functional preservation. Since the introduction of endolaryngeal laser arytenoidectomy, certain modifications have been described, such as partial resection procedures and mucosa sparing techniques as opposed to total arytenoidectomy. Discussion. The primary outcome measure in studies on BVFP treatment using total or partial arytenoidectomy is avoidance of tracheotomy or decannulation and reported success ranges between 90 and 100% in this regard. Phonation is invariably affected and arytenoidectomy worsens both aerodynamic and acoustic vocal properties. Recent reports indicate that partial and total arytenoidectomies have similar outcome in respect to phonation and swallowing. We use CO2 laser assisted partial arytenoidectomy with a posteromedially based mucosal flap for primary cases and reserve total arytenoidectomy for revision. Lateral suturing of preserved mucosa provides tension on the vocal fold leading to better voice and leaves no raw surgical field to unpredictable scarring or granulation. Conclusion. Arytenoidectomy as a permanent static procedure remains a traditional yet sound choice in the treatment of BVFP. Laser dissection provides a precise dissection in a narrow surgical field and the possibility to perform partial arytenoidectomy.

  2. Total and Partial Laser Arytenoidectomy for Bilateral Vocal Fold Paralysis

    PubMed Central

    Süslü, Nilda; Atay, Gamze; Özer, Serdar; Kuşçu, Oğuz; Sözen, Tevfik

    2016-01-01

    Introduction. Treatment for bilateral vocal fold paralysis (BVFP) has evolved from external irreversible procedures to endolaryngeal laser surgery with greater focus on anatomic and functional preservation. Since the introduction of endolaryngeal laser arytenoidectomy, certain modifications have been described, such as partial resection procedures and mucosa sparing techniques as opposed to total arytenoidectomy. Discussion. The primary outcome measure in studies on BVFP treatment using total or partial arytenoidectomy is avoidance of tracheotomy or decannulation and reported success ranges between 90 and 100% in this regard. Phonation is invariably affected and arytenoidectomy worsens both aerodynamic and acoustic vocal properties. Recent reports indicate that partial and total arytenoidectomies have similar outcome in respect to phonation and swallowing. We use CO2 laser assisted partial arytenoidectomy with a posteromedially based mucosal flap for primary cases and reserve total arytenoidectomy for revision. Lateral suturing of preserved mucosa provides tension on the vocal fold leading to better voice and leaves no raw surgical field to unpredictable scarring or granulation. Conclusion. Arytenoidectomy as a permanent static procedure remains a traditional yet sound choice in the treatment of BVFP. Laser dissection provides a precise dissection in a narrow surgical field and the possibility to perform partial arytenoidectomy. PMID:27830141

  3. Is robotic partial nephrectomy convenient for solitary kidney?

    PubMed Central

    Kaouk, Jihad H.; Malkoç, Ercan

    2016-01-01

    Nephron sparing surgery (NSS) is the gold standard treatment option for patients with a solitary kidney in order to preserve renal function. Open partial nephrectomy (OPN) has been long considered the standard care for NSS. Robotic partial nephrectomy (RPN) is being gradually used more commonly even for solitary kidney and complex tumors. There was no difference between RPN and OPN regarding the rate of intraoperative-postoperative complications and positive surgical margin (PSM) (RPN: 7.5%, OPN: 8%) for patients with solitary kidney who underwent partial nephrectomy for small renal masses. Warm ischemia time (WIT) in all of our studies was within the safe range of <25 minutes which is acceptable ischemia time for robotic approaches. More studies are needed in order to evaluate kidney function. In conclusion with increasing experience, solitary kidney tumors can be managed safely with robotic approach. For patients having complex tumors with a potential of WIT >25 minutes, administration of intracorporeal ice slush during surgery may be considered. PMID:27635284

  4. Epilepsy Surgery: An Evidence Summary

    PubMed Central

    2012-01-01

    Background The Medical Advisory Secretariat, the predecessor of Health Quality Ontario, published an evidence-based analysis on functional brain imaging. This analysis highlighted the low uptake of epilepsy surgery in Ontario and internationally. Objective The objective of this analysis was to review the effectiveness of epilepsy surgery at reducing seizure frequency, as well as the safety of epilepsy surgery. Data Sources The literature search included studies published between January 1995 and March 2012. Search terms included epilepsy, surgery, resection, safety, and complications. Review Methods Studies were eligible for inclusion if they included at least 20 patients undergoing surgery; had a comparison group of patients with epilepsy who were not undergoing surgery; and reported follow-up periods of at least 1 year. Outcomes of interest included seizure frequency and complications associated with surgery. Results Six systematic reviews reported pooled seizure-free rates that ranged from 43% to 75%. Two randomized controlled trials compared the effectiveness of epilepsy surgery with no surgery in patients with drug-refractory epilepsy. Both trials reported significant improvements in the seizure frequency in the surgery group compared with the nonsurgery group. Eight retrospective cohort studies reported on the safety of epilepsy surgery. Of the 2,725 patients included in these studies, there were 3 deaths reportedly related to surgery. Other complications included hemiparesis, infection, and visual field defects. The studies had long follow-up periods ranging from a mean of 2 to 7 years. Limitations The most recent randomized controlled trial was stopped early due to slow enrolment rates. Thus results need to be interpreted with caution. Conclusions There is high quality evidence that epilepsy surgery is effective at reducing seizure frequency. Two randomized controlled trials compared surgery to no surgery in patients with drug-refractory epilepsy. Both

  5. Acute Wernicke encephalopathy and sensorineural hearing loss complicating bariatric surgery.

    PubMed

    Jethava, Ashif; Dasanu, Constantin A

    2012-01-01

    Health-care professionals must be aware of the mandatory vitamin supplementation in patients status post bariatric surgery. A recent increase in the number of gastric bypass surgeries in US has been associated with a proportional increase in Wernicke encephalopathy reports. Subtle or atypical neurologic features are not uncommon. Our report is of a female patient with acute Wernicke encephalopathy accompanied by sensorineural hearing loss six weeks after bariatric surgery. The patient had only a partial recovery of her neurologic symptoms eightweeks after vigorous therapy for this condition. Symptomatic thiamine (vitamin B1) and vitamin B12 deficiencies are particularly concerning effects of bariatric procedures, as neurologic and cognitive deficits may be long lasting or even permanent despite aggressive replacement therapy.

  6. Anterior segment surgery early after corneal wound repair.

    PubMed Central

    Maul, E; Muga, R

    1977-01-01

    Penetrating wounds of the cornea require immediate repair, generally within 24 hours. Tight closure of the wound and a reformed anterior chamber are the primary goals of surgery. However, there is no guarantee that further surgery will not be required for maintaining the healthy function of the anterior segment. At the second operation the effect of the procedure on the previously repaired wound is of prime importance, since in many cases the operation needs to be done before corneal healing is completed. In our series the lens, which was either partially or completely cataractous at the initial operation, became intumescent at different times afterwards, and an immediate removal was necessary. No change in the preoperative wound sealing or transparency of the cornea could be detected after lens surgery performed between 24 hours and 21 days from the initial corneal repair. PMID:603786

  7. Markerless monocular tracking system for guided external eye surgery.

    PubMed

    Monserrat, C; Rupérez, M J; Alcañiz, M; Mataix, J

    2014-12-01

    This paper presents a novel markerless monocular tracking system aimed at guiding ophthalmologists during external eye surgery. This new tracking system performs a very accurate tracking of the eye by detecting invariant points using only textures that are present in the sclera, i.e., without using traditional features like the pupil and/or cornea reflections, which remain partially or totally occluded in most surgeries. Two known algorithms that compute invariant points and correspondences between pairs of images were implemented in our system: Scalable Invariant Feature Transforms (SIFT) and Speed Up Robust Features (SURF). The results of experiments performed on phantom eyes show that, with either algorithm, the developed system tracks a sphere at a 360° rotation angle with an error that is lower than 0.5%. Some experiments have also been carried out on images of real eyes showing promising behavior of the system in the presence of blood or surgical instruments during real eye surgery.

  8. Local excision by transanal endoscopic surgery

    PubMed Central

    García-Flórez, Luis J; Otero-Díez, Jorge L

    2015-01-01

    Transanal endoscopic surgery (TES) consists of a series of anorectal surgical procedures using different devices that are introduced into the anal canal. TES has been developed significantly since it was first used in the 1980s. The key point for the success of these techniques is how accurately patients are selected. The main indication was the resection of endoscopically unresectable adenomas. In recent years, these techniques have become more widespread which has allowed them to be applied in conservative rectal procedures for both benign diseases and selected cases of rectal cancer. For more advanced rectal cancers it should be considered palliative or, in some controlled trials, experimental. The role of newer endoscopic techniques available has not yet been defined. TES may allow for new strategies in the treatment of rectal pathology, like transanal natural orifice transluminal endoscopic surgery or total mesorectal excision. PMID:26309355

  9. The impact of marketing language on patient preference for robot-assisted surgery.

    PubMed

    Dixon, Peter R; Grant, Robert C; Urbach, David R

    2015-02-01

    Robot-assisted surgery is gaining momentum as a new trend in minimally invasive surgery. With limited evidence supporting its use in place of the far less expensive conventional laparoscopic surgery, it has been suggested that marketing pressure is partly responsible for its widespread adoption. The impact of phrases that promote the novelty of robot-assisted surgery on patient decision making has not been investigated. We conducted a discrete choice experiment to elicit preference of partial colectomy technique for a hypothetical diagnosis of colon cancer. A convenience sample of 38 participants in an ambulatory general surgery clinic consented to participate. Each participant made 2 treatment decisions between robot-assisted surgery and conventional laparoscopic surgery, with robot-assisted surgery described as "innovative" and "state-of-the-art" in one of the decisions (marketing frame), and by a disclosure of the uncertainty of available evidence in the other (evidence-based frame). The magnitude of the framing effect was large with 12 of 38 subjects (31.6%, P = .005) selecting robot-assisted surgery in the marketing frame and not the evidence-based frame. This is the first study to our knowledge to demonstrate that words that highlight novelty have an important influence on patient preference for robot-assisted surgery and that use of more neutral language can mitigate this effect.

  10. Partial-Payload Support Structure

    NASA Technical Reports Server (NTRS)

    Mitchell, R.; Freeman, M.

    1984-01-01

    Partial-payload support structure (PPSS) is modular, bridge like structure supporting experiments weighing up to 2 tons. PPSS handles such experiments more economically than standard Spacelab pallet system.

  11. [Postoperative complications in plastic surgery].

    PubMed

    Vogt, P M

    2009-09-01

    Plastic surgery covers a broad spectrum of diseases and conditions in the areas of reconstructive surgery, hand, burn and aesthetic surgery. Besides acquired defects or malformations an increasing number of patients are being treated for surgical or multimodal complications. In a considerable number of patients plastic and reconstructive surgery remains the only therapeutic alternative after other therapy has failed. Therefore complication management in plastic surgery is of utmost importance for a successful outcome. In addition patient expectations in the results of plastic surgery as a discipline of invention and problem solving are steadily increasing. This challenge is reflected in clinical patient management by intensive research in tissue engineering and regenerative medicine. Patients in plastic surgery are recruited from all age groups of either gender, involving traumatic and oncologic as well as congenital and aesthetic disorders. The demographics of aging, multimorbidity and obesity pose new challenges to plastic surgery. Although age over 70 years is not an independent risk factor per se for complications in plastic surgery, e.g. for complex free flap transfer, medical problems are present at a higher rate, which is to be expected in this age group. Risk factors such as alcoholism and coronary heart diseases seem to be independent predictors of perioperative complications. Therefore older patients can also benefit from plastic surgery and recurrent operations by the corresponding risk and complication management. Complication management necessitates careful patient selection, estimation of operative risks and patient-adapted selection of procedures. In addition to expertise in plastic surgery a thorough knowledge of non-surgical and surgical back-up procedures for technical incidents as well as vascular circulatory and wound healing disorders is required to deal successfully with complications in plastic surgery. This article presents these specific

  12. Global cancer surgery: delivering safe, affordable, and timely cancer surgery.

    PubMed

    Sullivan, Richard; Alatise, Olusegun Isaac; Anderson, Benjamin O; Audisio, Riccardo; Autier, Philippe; Aggarwal, Ajay; Balch, Charles; Brennan, Murray F; Dare, Anna; D'Cruz, Anil; Eggermont, Alexander M M; Fleming, Kenneth; Gueye, Serigne Magueye; Hagander, Lars; Herrera, Cristian A; Holmer, Hampus; Ilbawi, André M; Jarnheimer, Anton; Ji, Jia-Fu; Kingham, T Peter; Liberman, Jonathan; Leather, Andrew J M; Meara, John G; Mukhopadhyay, Swagoto; Murthy, Shilpa S; Omar, Sherif; Parham, Groesbeck P; Pramesh, C S; Riviello, Robert; Rodin, Danielle; Santini, Luiz; Shrikhande, Shailesh V; Shrime, Mark; Thomas, Robert; Tsunoda, Audrey T; van de Velde, Cornelis; Veronesi, Umberto; Vijaykumar, Dehannathparambil Kottarathil; Watters, David; Wang, Shan; Wu, Yi-Long; Zeiton, Moez; Purushotham, Arnie

    2015-09-01

    Surgery is essential for global cancer care in all resource settings. Of the 15.2 million new cases of cancer in 2015, over 80% of cases will need surgery, some several times. By 2030, we estimate that annually 45 million surgical procedures will be needed worldwide. Yet, less than 25% of patients with cancer worldwide actually get safe, affordable, or timely surgery. This Commission on global cancer surgery, building on Global Surgery 2030, has examined the state of global cancer surgery through an analysis of the burden of surgical disease and breadth of cancer surgery, economics and financing, factors for strengthening surgical systems for cancer with multiple-country studies, the research agenda, and the political factors that frame policy making in this area. We found wide equity and economic gaps in global cancer surgery. Many patients throughout the world do not have access to cancer surgery, and the failure to train more cancer surgeons and strengthen systems could result in as much as US $6.2 trillion in lost cumulative gross domestic product by 2030. Many of the key adjunct treatment modalities for cancer surgery--e.g., pathology and imaging--are also inadequate. Our analysis identified substantial issues, but also highlights solutions and innovations. Issues of access, a paucity of investment in public surgical systems, low investment in research, and training and education gaps are remarkably widespread. Solutions include better regulated public systems, international partnerships, super-centralisation of surgical services, novel surgical clinical trials, and new approaches to improve quality and scale up cancer surgical systems through education and training. Our key messages are directed at many global stakeholders, but the central message is that to deliver safe, affordable, and timely cancer surgery to all, surgery must be at the heart of global and national cancer control planning.

  13. Minimally invasive mediastinal surgery

    PubMed Central

    Melfi, Franca M. A.; Mussi, Alfredo

    2016-01-01

    In the past, mediastinal surgery was associated with the necessity of a maximum exposure, which was accomplished through various approaches. In the early 1990s, many surgical fields, including thoracic surgery, observed the development of minimally invasive techniques. These included video-assisted thoracic surgery (VATS), which confers clear advantages over an open approach, such as less trauma, short hospital stay, increased cosmetic results and preservation of lung function. However, VATS is associated with several disadvantages. For this reason, it is not routinely performed for resection of mediastinal mass lesions, especially those located in the anterior mediastinum, a tiny and remote space that contains vital structures at risk of injury. Robotic systems can overcome the limits of VATS, offering three-dimensional (3D) vision and wristed instrumentations, and are being increasingly used. With regards to thymectomy for myasthenia gravis (MG), unilateral and bilateral VATS approaches have demonstrated good long-term neurologic results with low complication rates. Nevertheless, some authors still advocate the necessity of maximum exposure, especially when considering the distribution of normal and ectopic thymic tissue. In recent studies, the robotic approach has shown to provide similar neurological outcomes when compared to transsternal and VATS approaches, and is associated with a low morbidity. Importantly, through a unilateral robotic technique, it is possible to dissect and remove at least the same amount of mediastinal fat tissue. Preliminary results on early-stage thymomatous disease indicated that minimally invasive approaches are safe and feasible, with a low rate of pleural recurrence, underlining the necessity of a “no-touch” technique. However, especially for thymomatous disease characterized by an indolent nature, further studies with long follow-up period are necessary in order to assess oncologic and neurologic results through minimally

  14. [Indications for cataract surgery].

    PubMed

    Gloor, B

    1982-09-01

    Progress in surgical methods and advances in the correction of aphakia with contact lenses or intraocular lenses on the one hand, and the greater demands made by patients on the other are the reasons why the cataract surgery is indicated much earlier today than 20 years ago. Occupational considerations and the visual acuity required to keep a driver's licence may be determining factors in the timing of surgery and the choice of one or the other methods o correcting aphakia. To advise the patient correctly, an accurate preoperative assessment of the visual function which can be expected postoperatively has be made. Of the preoperative examinations, results with the test wih the Moiré pattern following Lotmar are mentioned. If the patient's occupation places high demands on visual acuity, as e.g. for bus drivers - 1.0 on the better and 0.8 on the second eye - it seems less risky to go for a contact lens than for an intraocular lens (cystoid macular edema!). Advantages and disadvantages and the special indications and contraindications of correction with cataract glasses, with contact lenses or with different types of intraocular lenses are tabulated. The mathematical conditions which sampling statistics and the success rates of different types of intraocular lenses and surgical procedures have to fulfill, such as extracapsular versus intracapsular cataract extraction, are explained in order to provide a basis of knowledge rather than merely belief. Finally, the indications for different types of surgery in special situations and with different forms of cataract are described, e.g. phakolytic glaucoma, subluxation and luxation of the lens and congenital cataracts.

  15. [Robotics in pediatric surgery].

    PubMed

    Camps, J I

    2011-10-01

    Despite the extensive use of robotics in the adult population, the use of robotics in pediatrics has not been well accepted. There is still a lack of awareness from pediatric surgeons on how to use the robotic equipment, its advantages and indications. Benefit is still controversial. Dexterity and better visualization of the surgical field are one of the strong values. Conversely, cost and a lack of small instruments prevent the use of robotics in the smaller patients. The aim of this manuscript is to present the controversies about the use of robotics in pediatric surgery.

  16. Surgery for gastrinoma.

    PubMed

    Cisco, Robin M; Norton, Jeffrey A

    2007-01-01

    Surgery has been demonstrated to offer potential for cure in patients who have sporadic ZES and improved tumor-related survival in all patients who have ZES with gastrinomas larger than 2.5 cm. Techniques such as preoperative localization with SRS and intraoperative localization with duodenotomy have improved the effectiveness of surgical intervention for ZES. Future directions for investigation should include better defining the role of preoperative EUS and developing new, more sensitive techniques for preoperative localization. More research also is needed to define the appropriate indications for pancreaticoduodenectomy in ZES and to determine whether proximal vagotomy should be performed at the time of surgical exploration.

  17. Cutaneous mucormycosis postcosmetic surgery

    PubMed Central

    Al-Tarrah, Khaled; Abdelaty, Mahmoud; Behbahani, Ahmad; Mokaddas, Eman; Soliman, Helmy; Albader, Ahdi

    2016-01-01

    Abstract Background: Mucormycosis is a rare, aggressive, and life-threatening infection that is caused by organisms belonging to the order Mucorales. It is usually acquired through direct means and virtually always affects immunocompromised patients with the port of entry reflecting the site of infection, in this case, cutaneous. Unlike other mucormycoses, patients affected by Apophysomyces elegans (A elegans) are known to be immunocompetent. This locally aggressive disease penetrates through different tissue plains invading adjacent muscles, fascia, and even bone causing extensive morbidity and may prove fatal if treated inadequately. Cutaneous mucormycosis is associated with disruption of cutaneous barriers such as trauma. However, rarely, it may be iatrogenic. No cases have been previously reported postcosmetic surgery, especially one that is so commonly performed, lipofilling. Case Report: The patient is a, previously healthy, 41-year-old middle-eastern female who was admitted to the plastic surgery department 17 days after undergoing cosmetic surgery. She suffered from extensive tissue inflammation and necrosis in both gluteal regions. Following admission, she was initially started on empirical antimicrobial therapy which was changed to an antifungal agent, voriconazole, when preliminary microbiological results showed filamentous fungi. This was discontinued and liposomal amphotericin B was commenced when further mycological analysis identified A elegans. Furthermore, she underwent a total of 10 sessions of extensive debridement to the extent that portions of the sacrum and left femoral head became exposed. Her clinical status and wounds improved with the appropriate management and she remained an inpatient for 62 days. Subsequently, she had defects in both gluteal regions which required reconstructive surgery. Conclusion: A elegans is an uncommon cause of iatrogenic cutaneous mucormycosis. A high index of clinical suspicion is required, especially in the

  18. Penile surgery and reconstruction.

    PubMed

    Perovic, Sava V; Djordjevic, Miroslav L J; Kekic, Zoran K; Djakovic, Nenad G

    2002-05-01

    This review will highlight recent advances in the field of penile reconstructive surgery in the paediatric and adult population. It is based on the work published during the year 2001. Besides the anatomical and histological studies of the penis, major contributions have been described in congenital and acquired penile anomalies. Also, a few new techniques and modifications of old procedures are described in order to improve the final functional and aesthetic outcome. The techniques for penile enlargement present a trend in the new millennium, but are still at the stage of investigation.

  19. Monitoring in microvascular surgery.

    PubMed

    Furnas, H; Rosen, J M

    1991-03-01

    The importance of monitoring in microvascular surgery is underscored by the high reported salvage rates of failing free flaps and replants. In this overview, we begin by defining the physiology of ischemic tissue with emphasis given to the no-reflow phenomenon and the secondary critical ischemia times. Based on the physiological changes accompanying ischemia, several variables are defined that can be monitored to reflect the vascular state of a free flap or replant. Multifarious monitoring systems are then reviewed, including clinical observation, temperature, isotope clearance, ultrasonic Doppler, laser Doppler, transcutaneous oxygen tension, reflection plethysmography, dermofluorometry, pH, electromagnetic flowmetry, serial hematocrits, interstitial fluid pressure, and magnetic resonance imaging.

  20. Reoperative temporomandibular joint surgery.

    PubMed

    Vega, Luis G; Gutta, Rajesh; Louis, Patrick

    2011-02-01

    TMJ surgeries are not always successful. Many potential pitfalls can occur during any phase of the treatment and can lead to complications, less than desirable results, and short- or long-term failures. Unsatisfactory results can occur for multiple reasons, including misdiagnosis of the original pathologic condition, incorrect selection of surgical technique, technical failures, complications, systemic disease, and unrealistic expectations. This article focuses on the reoperation of the TMJ primarily in cases of internal derangement and discusses TMJ arthrocentesis, arthroscopy, modified condylotomy, and open joint procedures.