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Wilkiemeyer MB, Bieligk SC, Ashfaq R, Jones DB, Rege RV, Fleming JB. Laparoscopy alone is superior to peritoneal cytology in staging gastric and esophageal carcinoma. Surg Endosc 2004; 18:852-6. [PMID: 15054656 DOI: 10.1007/s00464-003-8828-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2003] [Accepted: 12/18/2003] [Indexed: 10/26/2022]
Abstract
BACKGROUND Laparoscopy identifies metastatic disease in patients with upper gastrointestinal malignancies; however, it has been suggested that cytological examination of peritoneal washings may increase the diagnostic yield. We hypothesize that the addition of cytologic washings to a standardized staging laparoscopy is unnecessary for the identification of intraabdominal metastasis in patients with gastric/esophageal cancer. METHODS Forty patients with gastric/esophageal cancer were prospectively evaluated. Patients successfully underwent a diagnostic laparoscopy protocol (with biopsies) during which peritoneal washings were obtained and processed for cytologic analysis. Laparoscopic versus cytologic identification of intraabdominal metastasis were compared. RESULTS Forty patients successfully completed laparoscopy with collection of peritoneal washings. Laparoscopic examination of the peritoneal cavity upstaged 21 (52.5%) patients. Laparoscopic examination consistently identified a statistically significant higher number of positive patients than cytologic examination of peritoneal washings (p = 0.001) and examination of cytologic washings alone failed to identify 45% of patients with positive findings and laparoscopy. The addition of cytologic examination added no additional stage IV patients to the laparoscopy-negative group. CONCLUSION A standardized laparoscopic examination alone is sufficient for the identification of intraabdominal metastatic disease in patients with gastric and esophageal cancer.
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Villegas L, Schneider BE, Callery MP, Jones DB. Laparoscopic skills training. Surg Endosc 2003; 17:1879-88. [PMID: 14577030 DOI: 10.1007/s00464-003-8172-3] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2003] [Accepted: 05/29/2003] [Indexed: 11/28/2022]
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Williams ML, Ilas D, Sajo E, Jones DB, Watkins KE. Deterministic photon transport calculations in general geometry for external beam radiation therapy. Med Phys 2003; 30:3183-95. [PMID: 14713085 DOI: 10.1118/1.1621135] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
A deterministic method is described for performing three-dimensional (3D) photon transport calculations of a LINAC head and phantom/patient geometry to obtain dose distributions for therapy planning. The space, energy, and directional-dependent photon flux density is obtained by numerically solving the Boltzmann equation in general 3D geometry using the method of characteristics. The deterministic transport calculations use similar ray tracing routines as found in Monte Carlo (MC) codes. A special treatment is developed to better represent the impact of scattering from accelerator head components. Equations are presented for computing the water kerma distribution due to the uncollided and collided photon flux density field in the patient region. Kerma results obtained from the deterministic computation are compared to Monte Carlo values for a variety of source spectra and field sizes. The agreement for kerma values in the beam is usually within the MC uncertainties. It is concluded that the deterministic method is a rigorous, first-principles approach that could provide a superior alternative to Monte Carlo calculations for some types of problems. However additional development is needed to provide capability for 3D electron transport calculations.
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Scott DJ, Villegas L, Sims TL, Hamilton EC, Provost DA, Jones DB. Intraoperative ultrasound and prophylactic ursodiol for gallstone prevention following laparoscopic gastric bypass. Surg Endosc 2003; 17:1796-802. [PMID: 12958683 DOI: 10.1007/s00464-002-8930-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2002] [Accepted: 10/22/2002] [Indexed: 10/26/2022]
Abstract
BACKGROUND Previous studies have shown that ursodiol decreases gallstone formation from 32% to 2% following open gastric bypass, but no data exist on laparoscopic Roux-en-Y gastric bypass (LRYGB) using intraoperative ultrasound (IOUS) screening. METHODS LRYGB with IOUS were performed on 195 consecutive patients. Patients with gallstones underwent simultaneous cholecystectomy, and patients without gallstones were prescribed ursodiol, 300 mg twice daily, for 6 month. Follow-up survey and ultrasound. RESULTS Of 195 patients, 44 (23%) had had a prior cholecystectomy, 21 (11%) underwent a simultaneous cholecystectomy, 129 (66%) had gallbladders left intact, and one (0.5%) false negative IOUS was excluded. Of 69 patients with ultrasound and survey follow-up (mean, 10 months), 19 (28%) developed gallstones seven with symptoms), and 50 (72%) were gallstone free. Forty-one percent of patients were compliant with ursodiol. There was no difference in compliance between patients with and without gallstones. In patients with gallstones, all of the symptomatic patients were noncompliant, whereas none of the compliant patients developed symptoms. Medication side-effects occurred in 17 of 69 patients (25%). CONCLUSIONS IOUS during LRYGB efficiently screens for gallstones, and selective cholecystectomy followed by prophylactic ursodiol results in low morbidity. Improvements in compliance may lower the incidence of postoperative gallstone formation.
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Wickham CL, Armitage H, Joyner MV, Sarsfield P, Boyce M, Wilkins BS, Jones DB, Ellard S. Quantitation of cyclin D1 over-expression using competitive fluorescent reverse transcription polymerase chain reaction: a tool for the differential diagnosis of mantle cell lymphoma. Med Oncol 2003; 20:77-85. [PMID: 12665688 DOI: 10.1385/mo:20:1:77] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2002] [Accepted: 11/11/2002] [Indexed: 11/11/2022]
Abstract
Mantle cell lymphoma is characterized by the presence of the t(11;14)(q13;q32) translocation that causes over-expression of the BCL-1 gene and consequent overproduction of its gene product cyclin D1. We have developed a competitive fluorescent reverse transcription polymerase chain reaction assay for the detection and semiquantitation of cyclin D1 over-expression. Using this assay a definitive ratio of the expression of cyclin D1 to cyclins D2 and D3 can be determined, provided good quality RNA is available. A single upstream primer derived from a consensus sequence found in cyclins D1, D2, and D3 was labeled at the 5' end using a fluorescent dye. Downstream primers specific to cyclins D1 and D2 were designed and used in conjunction with a previously published D3 specific primer. The fluorescently labeled PCR products were separated by electrophoresis using an ABI 377 DNA sequencer. Fluorescence emitted from each product was used to determine the ratio of expression of cyclin D1 to D2 and D3 by assigning a dosage quotient [D1/(D2+D3)]. The mean dosage quotient recorded from samples representing 29 non-MCL patients was 0.03 (SD +/- 0.03), the maximum value being 0.11. Samples from eight patients with a diagnosis of MCL generated values greater than 2. Calculation of a dosage quotient using this competitive fluorescent reverse transcription polymerase chain reaction assay allows unequivocal identification of patients with over-expression of cyclin D1, providing a new tool for the differential diagnosis of MCL.
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Elliott NC, Giles KL, Royer TA, Kindler SD, Tao FL, Jones DB, Cuperus GW. Fixed precision sequential sampling plans for the greenbug and bird cherry-oat aphid (Homoptera: Aphididae) in winter wheat. JOURNAL OF ECONOMIC ENTOMOLOGY 2003; 96:1585-1593. [PMID: 14650535 DOI: 10.1603/0022-0493-96.5.1585] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The numbers of greenbugs, Schizaphis graminum (Rondani), and bird cherry-oat aphids, Rhopalosiphum padi L., per wheat tiller (stem) were estimated in 189 production winter wheat (Triticum aestivum L.) fields located throughout Oklahoma. Taylor's power law regressions were calculated from these data and used to construct fixed precision sequential sampling schemes for each species. An evaluation data set was constructed from 240 samples taken during three growing seasons from winter wheat fields at four locations in Oklahoma. Wheat cultivar and growth stage were recorded for each field on the day of sampling. Taylor's power law parameters for evaluation fields differed significantly for both species among growing seasons, locations, and plant growth stages. Median precision achieved using the fixed precision sequential sampling schemes for each species departed <20% from expected precision over the range population intensity in the evaluation data. For the 10% of samples with greatest deviation between observed and expected precision, observed precision was 13.8-81.8% greater than that expected precision depending on aphid species and population intensity. For the greenbug, the distribution of the percentage deviation between observed and expected precision was positively skewed, so that the sampling scheme tended to over-predict precision. For the bird cherry-oat aphid, the distribution was more symmetric. Even though precision observed using the sampling schemes frequently varied from expected precision, because of the inevitable consequence of sampling error and environmental variation, the sampling schemes yielded median observed precision levels close to expected precision levels over a broad range of population intensity.
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Jones DB, Broeckmann E, Pohl T, Smith EL. Development of a mechanical testing and loading system for trabecular bone studies for long term culture. Eur Cell Mater 2003; 5:48-59; discussion 59-60. [PMID: 14562272 DOI: 10.22203/ecm.v005a05] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
A highly accurate (+/-3%) mechanical loading and measurement system combined with a trabecular bone diffusion culture-loading chamber has been developed, which provides the ability to study trabecular bone (and possibly) cartilage under controlled culture and loading conditions over long periods of time. The loading device has been designed to work in two main modes, either to apply a specific compressive strain to a trabecular bone cylinder or to apply a specific force and measure the resulting deformation. Presently, precisely machined bone cylinders can be loaded at frequencies between 0.1 Hz to 50 Hz and amplitudes over 7,000 microepsilon. The system allows accurate measurement of many mechanical properties of the tissue in real time, including visco-elastic properties. This paper describes the technical components, reproducibility, precision, and the calibration procedures of the loading system. Data on long term culture and mechanical responses to different loading patterns will be published separately.
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Hamilton EC, Sims TL, Hamilton TT, Mullican MA, Jones DB, Provost DA. Clinical predictors of leak after laparoscopic Roux-en-Y gastric bypass for morbid obesity. Surg Endosc 2003; 17:679-84. [PMID: 12618940 DOI: 10.1007/s00464-002-8819-5] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2002] [Accepted: 07/08/2002] [Indexed: 12/16/2022]
Abstract
BACKGROUND Gastrointestinal leak is a complication of laparoscopic Roux-en-Y gastric bypass (LRYGB). Contrast studies may underdiagnose leaks, forcing surgeons to rely solely on clinical data. This study was designed to evaluate various clinical signs for detecting leakage after LRYGB. METHODS We retrospectively reviewed 210 consecutive patients who underwent LRYGB between April 1999 and September 2001. There were nine documented leaks (4.3%). Clinical signs between patients with leaks (group 1) and those without leaks (group 2) were compared using univariate and multivariate logistic regression analysis. RESULTS Evidence of respiratory distress and a heart rate exceeding 120 beats per min were the two most sensitive indicators of gastrointestinal leak. Routine upper gastrointestinal contrast imaging detected only two of nine leaks (22%). CONCLUSION Leak after LRYGB may be difficult to detect. Evidence of respiratory distress and tachycardia exceeding 120 beats per min may be the most useful clinical indicators of leak after laparoscopic Roux-en-Y gastric bypass.
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Wilkins BS, Davis Z, Lucas SB, Delsol G, Jones DB. Splenic marginal zone atrophy and progressive CD8+ T-cell lymphocytosis in HIV infection: a study of adult post-mortem spleens from Côte d'Ivoire. Histopathology 2003; 42:173-85. [PMID: 12558750 DOI: 10.1046/j.1365-2559.2003.01569.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS Progressive changes have been reported in lymph nodes in HIV infection, but few accounts describe altered splenic histology at different stages of the disease. Investigation of splenic changes accompanying the progressive CD4+ T-cell depletion that occurs in HIV infection could shed light on normal immunological interactions in this organ. Therefore, we assessed the amount and distribution of lymphoid tissue in spleens from adults with documented early or advanced HIV disease. METHODS AND RESULTS Immunohistochemistry was used to study splenic tissue collected in an extensive autopsy survey of HIV+ adults in West Africa. Compared with post-mortem spleens from HIV- West African adults and control UK spleens, those from HIV-infected patients showed severe atrophy of white pulp B- and T-cell compartments. In early and advanced HIV disease, marginal zone atrophy was significant. Peri-arteriolar lymphoid sheaths contained increased numbers of CD8+/CD45RO+ T-cells in advanced HIV disease. In red pulp, early and advanced cases showed a lymphocytosis of CD8+/CD45RO- T-lymphocytes. CONCLUSIONS Atrophic changes were more extreme in advanced than early HIV infection. Reduced marginal zone function possibly explains the known predisposition of HIV+ patients to infection by encapsulated bacteria. Possible immunological consequences of these CD8+/CD45RO+ (peri-arteriolar lymphoid sheaths) and CD8+/CD45RO- (red pulp) responses deserve further study. Comparison of West African and UK control spleens indicated that there were no major ethnic differences in spleen structure to prevent extrapolation of our results to European adults.
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Abstract
Endoscopic ultrasound (EUS) comprises several techniques of performing high-frequency ultrasound via an endoscope placed in the gastrointestinal tract (oesophagus, stomach, duodenum and pancreaticobiliary tree and rectum). It has rapidly become an important tool in the investigation of a variety of lumenal disorders as well as locoregional staging of gastrointestinal malignancies. Needle biopsy of peri-intestinal structures, such as lymph nodes and pancreatic masses, can also be performed under real-time ultrasound control. To date, the utilization of this technology in Australia has been limited by cost constraints and a paucity of training opportunities. EUS continues to be a rapidly growing area in clinical gastroenterology. Recent studies continue to define its role, particularly in the loco-regional staging of a variety of malignancies. In addition, new instruments permit tissue sampling and a variety of therapeutic manoeuvres under direct ultrasound guidance.33; 26-32)
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Kondraske GV, Hamilton EC, Scott DJ, Fischer CA, Tesfay ST, Taneja R, Brown RJ, Jones DB. Surgeon workload and motion efficiency with robot and human laparoscopic camera control. Surg Endosc 2002; 16:1523-7. [PMID: 12098023 DOI: 10.1007/s00464-001-8272-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2002] [Accepted: 04/09/2002] [Indexed: 11/25/2022]
Abstract
BACKGROUND Surgeons are now being assisted by robotic systems in a wide range of laparoscopic procedures. Some reports have suggested that robot-assisted camera control (RACC) may be superior to a human driver in terms of quality of view and directional precision, as well as long-term cost savings. Therefore, we setout to investigate the impact of RACC of surgeon motion efficiency. METHODS Twenty pigs were randomized to undergo a standardized laparoscopic Nissen fundoplication with either a human or RACC system, the AESOP 2000. All procedures were performed by the same surgical fellow. Time was recorded for dissection and suture phases. Inertial motion sensors were used to monitor both the surgeon's hands and the camera. Digitized data were analyzed to produce summary measures related to overall motion. RESULTS The operative times were slightly longer with RACC (mean 80.2 +/- 20.6 vs 73.1 +/- 15.4 min, not significant). With regard to operative times and surgeon motion measures, the only statistically significant differences were for setup and breakdown times, which contributed <15% to the total time for the procedure. CONCLUSION In terms of impact on surgeon motion efficiency and operative time under normal surgical conditions, RACC is essentially the same as an expert human driver. However, careful planning and structuring of the surgical suite may yield some small gains in operative time.
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Douglas JM, Young WN, Jones DB. Lichtenstein inguinal herniorrhaphy using sutures versus tacks. Hernia 2002; 6:99-101. [PMID: 12209296 DOI: 10.1007/s10029-002-0052-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2001] [Accepted: 04/24/2002] [Indexed: 10/27/2022]
Abstract
The Lichtenstein hernia repair has become a popular technique for most inguinal hernias performed in the United States. One attempt to improve on this technique includes the use of a tacker instead of suturing the mesh. This study compared the feasibility and time saving for placement of mesh for open inguinal hernias with a tacker versus polypropylene suture.Thirty-four patients were prospectively randomized to undergo open hernia repair using either running 2-0 polypropylene suture or a tacker device that contained spiral titanium tacks. Patients were examined after 1 week and followed for a mean of 8 months (range 1-26 months) to record postoperative complications and technical failure rate. Mesh placement times were significantly shorter in the tacker group (9.0+/-3.5 min) than the suture group (30.9+/-9.9 min). No technical complications or recurrences were found in the follow-up period in either group.Securing mesh with the tacker is safe, and repair appears durable at short-term follow-up. Using the tacker on open inguinal hernia repairs shortens the time for mesh placement compared to suture fixation. Decreased operative time may reduce overall cost.
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Scott DJ, Fleming JB, Watumull LM, Lindberg G, Tesfay ST, Jones DB. The effect of hepatic inflow occlusion on laparoscopic radiofrequency ablation using simulated tumors. Surg Endosc 2002; 16:1286-91. [PMID: 11984682 DOI: 10.1007/s004640080167] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2000] [Accepted: 02/23/2001] [Indexed: 10/26/2022]
Abstract
BACKGROUND The purpose of this study was to determine the effect of hepatic inflow occlusion (the Pringle maneuver) on laparoscopic radiofrequency (RF) ablation. METHODS Using a previously validated agarose tissue-mimic model, 1-cm simulated hepatic tumors (three per animal) were laparoscopically ablated in five pigs with normal perfusion and then in five pigs with hepatic artery and portal vein occlusion. Energy was applied until tissue temperature reached 100 degrees C (warm-up) and thereafter for eight min. Specimens were examined immediately after treatment. RESULTS Vascular occlusion was successful in all cases per color-flow Doppler ultrasound. Pringle time was 11.4 +/- 1.6 min. Warm-up time (2.7 +/- 1.4 vs 20.2 +/- 14.0 min) was significantly faster in the Pringle group. Ablation diameter (34.8 +/- 2.9 vs 24.7 +/- 3.1 mm), proportion of round/ovoid lesions (93% vs 20%), ablation symmetry (100% vs 40%), and margin distance (5.1 +/- 3.0 vs 1.1 +/- 1.2 mm) were significantly better for the Pringle group than the No Pringle group, respectively. CONCLUSION Using a Pringle maneuver during laparoscopic RF ablation significantly enhances ablation geometry and results in larger margins.
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Kaffes AJ, Mishra A, Simpson SB, Jones DB. Upper gastrointestinal endoscopic ultrasound and its impact on patient management: 1990-2000. Intern Med J 2002; 32:372-8. [PMID: 12162393 DOI: 10.1046/j.1445-5994.2002.00250.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Endoscopic ultrasound (EUS) is a relatively new method used in the investigation and staging of upper gastrointestinal tract (UGIT) disease. AIMS To review practice and outcomes of EUS in an Australian university teaching hospital. METHODS The first part of the study was a retrospective review of indications, safety, referral patterns and technical difficulties of all EUS procedures performed at Concord Hospital, New South Wales, Australia, over a 10-year period from 1990 to 2000. The second part of the study examined the impact of EUS on the management of 225 consecutive cases, as determined by a questionnaire completed by each of the referring doctors. RESULTS A total of 537 EUS examinations was performed over the 10-year period. Indications for EUS included: (i) assessment of oesophageal lesions (241), (ii) assessment of gastric lesions (184) and (iii) assessment of pancreaticobiliary (112) disease. Cancer staging was performed in 46.7% of oesophageal and 31.4% of gastric cases. Sedation was achieved using intravenous midazolam (5.3+/-1.3 mg; mean +/- SD) and 52% of cases required additional intravenous pethidine (48.5+/-10.0 mg; mean +/- SD). Technical difficulties were encountered in 11% of cases and these were mainly related to nontraversable luminal stricturing. Of the 537 referrals, 48.2% were from within Central Sydney Area Health Services, and the remainder were from other Sydney hospitals, New South Wales regional centres and interstate. Of 225 questionnaires sent to referring doctors, 146 questionnaires were completed and returned for analysis. EUS aided staging of malignant disease, and confirmed or established a diagnosis in 86% of cases. The diagnostic accuracy of EUS was 76% when confirmed histologically. EUS avoided further diagnostic investigations in the majority of cases and in 25% of cases surgery was avoided. Fine-needle aspiration biopsy (FNAB) during EUS would have been useful in 30% of cases. Overall, clinical decision-making and management were changed in one-third of cases. CONCLUSIONS Endoscopic ultrasound is an accurate, safe and useful imaging method in UGIT disease. The increasing demand for EUS and EUS-guided FNAB suggests an expanding future for EUS in Australia.
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Hamilton EC, Scott DJ, Fleming JB, Rege RV, Laycock R, Bergen PC, Tesfay ST, Jones DB. Comparison of video trainer and virtual reality training systems on acquisition of laparoscopic skills. Surg Endosc 2002; 16:406-11. [PMID: 11928017 DOI: 10.1007/s00464-001-8149-z] [Citation(s) in RCA: 225] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2001] [Accepted: 06/28/2001] [Indexed: 10/28/2022]
Abstract
Training on a video trainer or computer-based minimally invasive surgery trainer leads to improved benchtop laparoscopic skill. Recently, improved operative performance from practice on a video trainer was reported. The purpose of this study was three fold: (a) to compare psychomotor skill improvement after training on a virtual reality (VR) system with that after training on a video-trainer, (VT) (b) to evaluate whether skills learned on the one training system are transferable to the other, and (c) to evaluate whether VR or VT training improves operative performance. For the study, 50 junior surgery residents completed baseline skill testing on both the VR and VT systems. These subjects then were randomized to either a VR or VT structured training group. After practice, the subjects were tested again on their VR and VT skills. To assess the effect of practice on operative performance, all second-year residents (n = 19) were evaluated on their operative performance during a laparoscopic cholecystectomy before and after skill training. Data are expressed as percentage of improvement in mean score/time. Analysis was performed by Student's paired t-test. The VR training group showed improvement of 54% on the VR posttest, as compared with 55% improvement by the VT group. The VR training group improved more on the VT posttest tasks (36%) than the VT training group improved on the VR posttest tasks (17%) (p <0.05). Operative performance improved only in the VR training group (p <0.05). Psychomotor skills improve after training on both VR and VT, and skills may be transferable. Furthermore, training on a minimally invasive surgery trainer, virtual reality system may improve operative performance during laparoscopic cholecystectomy.
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Hamilton EC, Scott DJ, Kapoor A, Nwariaku F, Bergen PC, Rege RV, Tesfay ST, Jones DB. Improving operative performance using a laparoscopic hernia simulator. Am J Surg 2001; 182:725-8. [PMID: 11839347 DOI: 10.1016/s0002-9610(01)00800-5] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Traditionally, the acquisition of surgical skill has occurred entirely in the operating room. To meet the expanding challenges of cost containment and patient safety, novel methods of surgical training utilizing ex-vivo workstations are being developed. The purpose of our study was to evaluate the impact of a laparoscopic training curriculum on surgical residents' operative performance. METHODS Twenty-one surgery residents completed baseline laparoscopic total extraperitoneal (TEP) hernia repairs. Operative performance was evaluated using a validated global assessment tool. Each resident was then randomized to a control group or a trained group. A CD ROM, video, and simulator were used for training. At the end of the study, each resident's operative performance was again evaluated. RESULTS Improvement was significantly greater in the trained group in five of the eight individual global assessment areas as well as the composite score (P <0.05). Questionnaire data suggested that training resulted in improved understanding of the TEP hernia repair (P = 0.01) and an increased willingness to offer the operation to patients with nonrecurrent unilateral hernias (P = 0.02). CONCLUSIONS A multimodality laparoscopic TEP hernia curriculum improves residents' knowledge of the TEP hernia repair and comfort in performing the procedure, and may also improve actual operative performance.
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Traxer O, Gettman MT, Napper CA, Scott DJ, Jones DB, Roehrborn CG, Pearle MS, Cadeddu JA. The impact of intense laparoscopic skills training on the operative performance of urology residents. J Urol 2001; 166:1658-61. [PMID: 11586196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
PURPOSE As laparoscopy has become more commonplace in urology, increased emphasis has been placed on laparoscopic education. We assessed the impact of laparoscopic skills training on the operative performance of urological surgeons inexperienced with laparoscopy. MATERIALS AND METHODS Urology residents were prospectively randomized to undergo laparoscopic skills training (6) or no training (6). Baseline assessment of operative performance (scale 0 to 35) during porcine laparoscopic nephrectomy was completed by all subjects. Cumulative time to complete laparoscopic tasks using an inanimate trainer was also recorded. The skills training group then practiced inanimate trainer tasks for 30 minutes daily for 10 days. The 2 groups then repeated the timed inanimate trainer tasks and underwent repeat assessment of the ability to perform porcine laparoscopic nephrectomy. RESULTS At baseline no statistical difference was noted in laparoscopic experience, inanimate trainer time or overall operative assessment in the 2 groups. In the skills training group mean cumulative time to complete inanimate trainer tasks decreased from 341 to 176 seconds (p = 0.003), while in the control group it decreased from 365 to 301 (p = 0.15). Operative assessment improved from initial to repeat porcine laparoscopic nephrectomy regardless of the trained versus control randomization grouping (22.0 to 27.8, p = 0.0008 and 20.8 to 26.5, p = 0.00007, respectively). CONCLUSIONS In vivo experience enables urological surgeons inexperienced with laparoscopy to improve significantly in all aspects of complex laparoscopic procedures. In this pilot study the magnitude of improvement was independent of additional training in laparoscopic skills. Educational curriculum should include in vivo practice in addition to skills training.
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Stewart MG, Jones DB, Garson AT. An incentive plan for professional fee collections at an indigent-care teaching hospital. ACADEMIC MEDICINE : JOURNAL OF THE ASSOCIATION OF AMERICAN MEDICAL COLLEGES 2001; 76:1094-1099. [PMID: 11704508 DOI: 10.1097/00001888-200111000-00009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The authors describe the implementation and development of an incentive plan to improve professional fee collections at an indigent-care teaching hospital. They theorized that an incentive plan based on relative value unit (RVU) productivity would increase billings and collections of professional fees. Unique RVU targets were set for individual services based on the number of faculty full-time equivalents and average reported productivity for academic physicians by specialty. The incentive plan was based on the level of expected faculty billings, measured in RVUs, for each department. A "base + incentive" model was used, with the base budget being distributed monthly throughout the year, and the incentive held as a "withhold" to be paid at the year's end only if the billing target in RVUs was met. Additionally, a task force worked with physician billing office and the hospital to improve collections. In the first year after implementation of the system was in place, important increases were noted in total RVU productivity (30.5% over the previous year) and in collections (49.5% over the previous year). Sixteen of 23 departments exceeded their incentive targets, and it was possible to make distributions of professional fees to those departments, to be used within the hospital system to enhance clinical services. Moreover, the plan created an overall positive attitude toward billings and documentation of faculty activities. The authors believe that this kind of incentive plan will be increasingly important for academic faculty working in public hospital systems.
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Roland PS, Shoup AG, Shea MC, Richey HS, Jones DB. Verification of improved patient outcomes with a partially implantable hearing aid, The SOUNDTEC direct hearing system. Laryngoscope 2001; 111:1682-6. [PMID: 11801925 DOI: 10.1097/00005537-200110000-00002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Partially implantable hearing devices have been developed to address some of the user-perceived shortcomings of standard amplification systems. Partially implantable devices are purported to provide improved sound quality as a result of decreased occlusion, decreased feedback, and enhanced clarity resulting from increased high-frequency gain. Such improvements may result in greater user satisfaction. To justify selection of a partially implantable device and undergoing a minor surgical procedure, verification techniques must be used to document user improvement or increased satisfaction over conventional amplification. OBJECTIVE To evaluate patient satisfaction with the SOUNDTEC direct hearing system. STUDY DESIGN Within-subjects repeated measures design. METHODS Objective and subjective evaluation pre- and post-implantation with the SOUNDTEC device. Verification techniques included tonal functional gain measures with traditional amplification and the SOUNDTEC device, word recognition in quiet (NU-6) and in noise (SPIN), the Abbreviated Profile of Hearing Aid Benefit (APHAB), and the Hough Ear Institute Profile (HEIP). RESULTS Although there was no significant difference between optimal traditional amplification and the SOUNDTEC device for speech perception measures, the SOUNDTEC device yielded statistically significant increased high-frequency functional gain. Subjective reports indicated that the SOUNDTEC device provides a cleaner, more natural sound without feedback than traditional amplification. CONCLUSIONS Partially implantable hearing aids may address some of the limitations of traditional amplification systems.
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Scott DJ, Provost DA, Tesfay ST, Jones DB. Laparoscopic Roux-en-Y gastric bypass using the porcine model. Obes Surg 2001; 11:46-53. [PMID: 11361168 DOI: 10.1381/096089201321454105] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The laparoscopic Roux-en-Y gastric bypass (LRYGBP) may be performed using a variety of methods. The purpose of this study was to learn how to perform the Roux-en-Y gastric bypass operation laparoscopically, using a porcine model. MATERIALS AND METHODS 11 domestic pigs (mean weight 47 kg) underwent LRYGBP. In 8 animals, a completely laparoscopic approach was attempted, while in 3 animals a hand-assist device was used. Techniques for anvil placement, pouch calibration, and limb-length measurement were evaluated. Animals were sacrificed at the end of the procedure, and operative results were recorded. RESULTS The hand-assist device restored tactile feedback but obscured visualization. The gastrojejunostomy leak rate was 64%, and the jejunojejunostomy leak rate was 73%. Anvil placement using transgastric and transoral methods was feasible. Calibrating the pouch with a Baker's tube was more accurate than using anatomical landmarks. Measuring limb-lengths using Babcock clamps was reliable with practice. CONCLUSION The frailty of the porcine small intestine may limit one's ability to achieve intact anastomoses. Despite the anatomic limitations, the porcine model was well-suited for skill development and evaluation of techniques for performing the LRYGBP operation.
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Abstract
BACKGROUND The purpose of this study was to quantify the learning curve of a previously validated laparoscopic skills curriculum. METHODS Second-year medical students (MS2, n = 11) and second (PGY2, n = 11) and third (PGY3, n = 6) year surgery residents were enrolled into a curriculum using five video-trainer tasks. All subjects underwent baseline testing, training (30 minutes per day for 10 days), and final testing. Scores were based on completion time. The relationship between task completion time and the number of practice repetitions was examined. Improvement (the difference in baseline and final performance) amongst groups was compared by one-way analysis of variance using the baseline score as a covariate; P <0.05 indicated significance. RESULTS Baseline scores were not significantly different. Final scores were significantly better for MS2s versus PGY3s. Adjusted-improvement was significantly larger for the MS2s compared with PGY2s and PGY3s, and for PGY2s compared with PGY3s. The mean number of repetitions corresponding to a predicted 90th percentile score was 32. CONCLUSION Inexperienced subjects benefit the most from skills training. For maximal benefit, we recommend that each task be practiced for at least 30 to 35 repetitions.
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Wilkins BS, Buchan SL, Webster J, Jones DB. Tryptase-positive mast cells accompany lymphocytic as well as lymphoplasmacytic lymphoma infiltrates in bone marrow trephine biopsies. Histopathology 2001; 39:150-5. [PMID: 11493331 DOI: 10.1046/j.1365-2559.2001.01173.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
AIMS To investigate the specificity of increased bone marrow mast cell numbers in lymphoplasmacytic lymphoma (LPL) and to evaluate the relationship between mast cell number and the immunoglobulin phenotype of neoplastic lymphoid cells. METHODS AND RESULTS Retrospective study of bone marrow trephine biopsy specimens from patients with LPL, compared with selected cases representing chronic lymphocytic leukaemia (CLL) and multiple myeloma (MM) of known immunoglobulin light and heavy chain phenotype. Bone marrow mast cells were counted following immunohistochemical staining of sections for mast cell tryptase. We have confirmed previous observations that mast cell numbers are increased in bone marrow infiltrates of LPL. However, we found similarly high mast cell numbers in CLL. High mast cell numbers were associated with neoplastic lymphoid cells expressing an IgM kappa phenotype. Mast cell numbers were low in all cases of MM studied and in controls with no lymphoma present. We observed an apparent bias towards kappa light chain expression in our cases of LPL. CONCLUSIONS Mast cell number should not be considered a reliable factor in the differential diagnosis of LPL and CLL when assessing bone marrow histology. Possible bias towards kappa light chain expression in LPL requires further study, as do the mechanism and functions of mast cell recruitment by neoplastic lymphoid cells.
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Smith ST, Scott DJ, Burdick JS, Rege RV, Jones DB. Laparoscopic marsupialization and hemisplenectomy for splenic cysts. J Laparoendosc Adv Surg Tech A 2001; 11:243-9. [PMID: 11569516 DOI: 10.1089/109264201750539781] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Splenic cysts are a rare clinical entity in the United States, and historically, management has consisted of either partial or total splenectomy via an open approach. Laparoscopic treatment of splenic cysts with preservation of splenic parenchyma offers several advantages. Compared with the open approach, a laparoscopic approach may result in less postoperative pain and a more rapid return to full activity. Compared with total splenectomy, splenic preservation eliminates the risk of overwhelming postsplenectomy infection. PATIENTS AND METHODS We present two patients with splenic cysts. One patient was treated with laparoscopic marsupialization of the cyst and the other with laparoscopic hemisplenectomy. RESULTS Both patients are without further symptoms at 26 and 5 months' follow-up, respectively. CONCLUSIONS Laparoscopic marsupialization and hemisplenectomy are appropriate treatment options for patients with splenic cysts.
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Jones DB, Niendorff WJ, Broderick EB. A review of the oral health of American Indian and Alaska Native elders. J Public Health Dent 2001; 60 Suppl 1:256-60. [PMID: 11243044 DOI: 10.1111/j.1752-7325.2000.tb04071.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES This paper reviews the demographics, access to care barriers, and the oral health of American Indian and Alaska Native (Native American) elders aged 65 years and older using complete tooth loss as a measure to compare with the US population. Strategies for improving oral health and increasing access to care for Native American elders also are discussed. METHODS We reviewed the results from patient surveys conducted by the Indian Health Service (1983-84 and 1991) and data from other sources, including the second International Collaborative Study of Oral Health Outcomes (ICS-II) conducted in 1990 on the Sioux and Navajo reservations. We compared complete tooth loss data from these studies with findings of the 1985 National Institute of Dental Research Oral Health Survey of US Employed Adults and Seniors and the Third National Health and Nutrition Examination Survey (NHANES III). RESULTS The 1991 Indian Health Service (IHS) patient survey reported a complete tooth loss prevalence of 42 percent among elders. Although it is based on a patient sample, this finding is comparable to the rate of 40 percent found among a random sample of Navajo and Lakota adults aged 65-74 years reported in the ICS-II study. The 1991 IHS patient survey also found complete tooth loss among diabetics to be much higher than among nondiabetics. CONCLUSIONS The prevalence of complete tooth loss for Native American elders is higher than in population surveys of US elders based on random samples. The actual prevalence of complete tooth loss is probably even higher in Native American elders because estimates presented in this paper are clinic based.
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