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Learning Curve (learning + curve)
Kinds of Learning Curve Selected AbstractsPhased-Array Intracardiac Echocardiography for Guiding Transseptal Catheter Placement: Utility and Learning CurvePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 4 2002SUSAN B. JOHNSON JOHNSON, S.B., et al.: Phased-Array Intracardiac Echocardiography for Guiding Transseptal Catheter Placement: Utility and Learning Curve. The utility of a new intracardiac 64-element, phased-array, longitudinal ultrasound imaging system for guiding transseptal catheterization was assessed during 69 crossing attempts in 45 dogs because of the inherent limitations of fluoroscopy and mechanical ultrasound. Multifrequency (7.5,8.5 MHZ) imaging of the membranous fossa ovalis, posterior left atrium, and left atrial appendage was conducted from the right atrium. Contact of the Brockenbrough needle with the interatrial septum as reflected by membranous fossa ovalis "tenting" was uniformly identified. Transseptal crossing and advancement of the dilator and sheath were adequately imaged because of deeper ultrasound tissue penetration. Transseptal catheterization was successfully accomplished in 44 of 45 dogs: on the first attempt in 40 and with additional attempts in 4 and confirmed by direct far-field imaging of nonagitated saline injection via the sheath. Total transseptal catheterization time was 3.0 ± 1.8 minutes. Unsuccessful first attempts and/or subsequent sheath pullback into the right atrium with catheter manipulation were also readily recognized. Insertion of the transseptal needle beyond the ultrasound imaging plane resulted in perforation of the posterior left atrial wall in three attempts. Accompanying effusions in these animals and three others related to subsequent intracardiac ablation catheter manipulation were readily identified and monitored echocardiographically. In conclusion, phased-array intracardiac imaging provides a highly reliable means of guiding transseptal access to the left atrium. In addition, inadvertent complications such as perforation and pericardial effusion development can be readily recognized. [source] Outcomes in Laryngeal Cancer: A Product of the Learning Curve?THE LARYNGOSCOPE, Issue 9 2006Jonas Johnson MD No abstract is available for this article. [source] Learning Curve for Translaryngeal Tracheotomy in Head and Neck SurgeryTHE LARYNGOSCOPE, Issue 4 2001Gioacchino Giugliano MD Abstract Objectives Translaryngeal tracheotomy (TLT) is a widely accepted procedure in intensive-care units for its simplicity of execution, low morbidity, rapid wound closure after cannula removal, good esthetic results, and lack of long-term sequelae. The aim of this study was to evaluate the feasibility and use of adopting TLT in patients with cancer undergoing major head and neck surgery. Study Design Prospective analysis of learning curve and incidence of complications in 41 patients with cancer who underwent TLT at the Division of Head and Neck Surgery of the European Institute of Oncology from November 1997 to June 1999. Methods Patient characteristics, pathology, anatomic characteristics of the neck, and surgical short-term and long-term complications were noted. The patients were divided into consecutive groups of six or seven patients, and time trends in occurrence of complications and time to execute the procedure were assessed. Results TLT performance time decreased from 50 minutes in the first seven patients to 24 minutes in the last group. The technique was easy to perform and safe, with only two minor complications during surgery. However, minor complications occurred in three and major complications in 17 patients in the days immediately following surgery, almost entirely attributable to lack of counter-cannu1a and stylet. Conclusions In view of the high proportion of major complications, TLT using the presently available kit is unsuitable for major head and neck surgery. However, the considerable advantages of the technique would recommend it as a valid alternative to surgical tracheotomy if the kit included a counter-cannu1a and stylet. [source] Robotic-assisted laparoscopic radical prostatectomy: Learning curve of first 100 casesINTERNATIONAL JOURNAL OF UROLOGY, Issue 7 2010Yen Chuan Ou Objective: Robotic-assisted laparoscopic radical prostatectomy (RALP) is gaining popularity for treating localized prostate cancer. We aimed to analyze the learning curve of a single surgeon using RALP in Taiwan. Methods: Medical records of 100 consecutive patients who underwent RALP were retrospectively reviewed. Preoperative, perioperative and postoperative parameters between patients in the first 30 cases (Group I), the second 30 cases (Group II) and cases 61,100 (Group III) undergoing RALP were analyzed. Results: Console time was shorter and blood loss was reduced in Groups II and III compared with Group I. Significant differences were found in vesicourethral anastomosis time (46.38 min for Group I vs 31.0 min for Group II vs 27 min for Group III, P < 0.01). Postoperative stay became statistically significantly shorter, from 7.33 days for Group I to 3.93 days for Group II to 3.0 days for Group III. Positive surgical margin of pT2 was reduced (13.3% for Group I, 7.1% for Group II and 0% for Group III) but not of pT3 (86.7% for Group I, 75% for Group II and 62.9% for Group III). Continence rate at 3 months was higher in Groups II (95%) and III (96.6%) than in Group 1 (76.7%, P < 0.05). Conclusions: For every 30 cases of RALP, vesicourethral anastomosis time and postoperative stay were significantly shorter. However, the incidence of surgical margin in pT3 prostate cancer was not significantly reduced. A learning curve of more than 100 cases is required to decrease the positive surgical margin in pT3 tumors. [source] Learning curve of hand-assisted retroperitoneoscopic nephrectomy in less-experienced laparoscopic surgeonsINTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2005AKIHIRO KAWAUCHI Abstract Aim:, To evaluate the learning curve of hand-assisted retroperitoneoscopic nephrectomy (HALS) performed by less-experienced surgeons. Methods:, The operative records of 166 patients, including 103 with renal tumors and 63 with renal pelvic or ureteral tumors, who underwent HALS performed by 18 less-experienced urologists were reviewed. Results:, The insufflation time in the first four cases was significantly longer than that in the sixteenth and later cases. The insufflation time in cases 5,10 was 14,24 min longer than that in the cases 16 onward, although the differences were not significant. The estimated blood loss did not differ in each group of cases. The complication rate in early cases, in which the operators' experience was five cases or less, was 6% (4/71), while that in later cases was also 7% (7/95). In the analysis of the learning curve of a single surgeon who performed 57 procedures, the insufflation time in cases 1,5 was significantly longer than in cases 41,57. The insufflation times in cases 5,10 were 45 min longer than those in cases 41,57, although the difference was not significant. The estimated blood loss did not differ in each group of cases. Complications did not seem related to operation experience. Conclusion:, In HALS, 5,10 cases were necessary for less-experienced urologists to gain average operating skills for this procedure. It may be reasonable for less-experienced surgeons to begin standard laparoscopic procedures after experiencing 10 cases of the present procedure. [source] Learning curve in cytoreductive surgery and hyperthermic intraperitoneal chemotherapyJOURNAL OF SURGICAL ONCOLOGY, Issue 4 2009Bijan N. Moradi III MS Abstract Cytoreductive surgery and Hyperthermic Intraperitoneal Chemotherapy have achieved good long-term results in patients with complete surgical eradication of their peritoneal dissemination but at the expense of significant perioperative morbidity and mortality. The high complication rate has been attributed to the steep learning curve associated with this procedure. We report on the current literature regarding the learning curve for this procedure and the key components that determine the success in learning this new skill. J. Surg. Oncol. 2009;100:293,296. © 2009 Wiley-Liss, Inc. [source] O-12 BLAND DYSKARYOSIS: A NEW PITFALL IN THINPREP® LIQUID BASED CYTOLOGYCYTOPATHOLOGY, Issue 2006M. A. Lynch Liquid based cytology (LBC) has improved cell visualization and preservation in cervical cytology. There has been a reduction in inadequate rate and some data to suggest an increase in sensitivity for dyskaryosis. Training for LBC has focused on differences in distribution of abnormal cells, but in most cases the morphological appearance of the dyskaryotic cells themselves is similar to that seen in conventional cytology. We are describing a new presentation of dyskaryosis which may be a cause of false negative cytology. We have referred to this as ,Bland dyskaryosis' because cells appear deceptively bland on low power examination, and can be misinterpreted as metaplastic or endocervical cells. Bland dyskaryosis cells are seen in groups. The architecture of the group is very disorganized, and adjacent cells show variation in size. Cells have a high nuclear/cytoplasmic ratio and smooth nuclear membranes. Chromatin is finely granular and evenly distributed. This is an unusual presentation of high-grade dyskaryosis and we feel that there is a learning curve in laboratories converting to liquid based cytology. The spectrum of appearances of squamous dyskaryosis needs to be delineated to allow further increases in sensitivity for dyskaryosis. [source] Novel Pretrichial Browlift Technique and Review of Methods and ComplicationsDERMATOLOGIC SURGERY, Issue 9 2009COURTNEY S. McGUIRE BS BACKGROUND The upper third of the face is integral to our perception of youth and beauty. While the eyelids anchor this facial cosmetic unit, the eyebrows and forehead are intrinsically linked to the upper eyelids, and their position and texture play an important role in creating pleasing eyes as well as conveying mood and youth. The most common browlifts are performed with endoscopic visualization. Yet, this technique requires special equipment and a prolonged learning curve. OBJECTIVE To demonstrate a novel pretrichial technique and to review different browlift methods and their potential adverse effects. METHODS Case series and review of the literature. RESULTS The pretrichial browlift results in a mild to moderate browlift with secondary smoothing of the forehead topography. Aside from bruising and swelling, it results in minimal adverse effects. Other techniques are also effective but may create a larger scar such as a direct browlift, may be more difficult in terms of approach such as the browpexy, or require endoscopes. CONCLUSION Browlifts are an important procedure in rejuvenating the upper third of the face and improving the overall facial aesthetic appearance. The pretrichial browlift is a less invasive open technique that is safe and effective for the appropriate patient. [source] ENDOSCOPIC SUBMUCOSAL DISSECTION IN THE UPPER GASTROINTESTINAL TRACT: PRESENT AND FUTURE VIEW OF EUROPEDIGESTIVE ENDOSCOPY, Issue 2009Horst Neuhaus In Western countries endoscopic mucosal resection (EMR) has been widely accepted for treatment of early Barrett`s neoplasia and flat or depressed colorectal adenomas. In contrast endoscopic submucosal dissection (ESD) is infrequently performed for several reasons. It seems to be difficult to overcome the learning curve of this difficult technique because of the low case volume of early gastric cancer. On the other hand ESD of esophageal or colorectal lesions is even more challenging and is considered to be inappropriate for learning. In addition the indication for esophageal or colorectal ESD is controversial in view of excellent results of the well established EMR technique which is less time-consuming and safer than ESD. A recent survey of leading Western endoscopy centers indicated the limited experience with ESD with a low number of cases for all potential indications. Only a few training courses have been established and the number of ongoing clinical studies is limited. Only 12 out of 340 published articles on "endoscopic mucosal dissection" were reported from Western countries. A better acceptance of ESD requires improvement of the technique to allow an easier, faster and safer approach. There is a strong demand for structured training courses and limitations of human cases to selected centers which participate in prospective trials. A close collaboration between Western and Asian centers is recommended for improvement of the ESD technique and its clinical application. [source] ENDOSCOPIC SUBMUCOSAL DISSECTION FOR ESOPHAGEAL SQUAMOUS CELL NEOPLASMSDIGESTIVE ENDOSCOPY, Issue 2 2009Mitsuhiro Fujishiro Endoscopic submucosal dissection (ESD) has gradually gained acceptance as one of the standard treatments for early esophageal cancer, as well as for early gastric cancer in Japan, but standardization of the knowledge is still incomplete. The final goal to perform ESD is not to resect the lesion in an en bloc fashion, but to save the patient from esophageal cancer-related death. Thus, the indications should be considered based on the entire patient, not just the target lesion itself, and pre-, peri- and postoperative management of the patient is also very important, as well as technical aspects of ESD. In terms of the techniques of ESD, owing to refinement of the procedural strategy, invention of the devices, and the learning curve, acceptable safety and favorable middle-term efficacy have been obtained. We believe that ESD will become a standard treatment for early esophageal cancer not only in Japan but also worldwide in the near future. [source] The Health Sector Gap in the Southern Africa Crisis in 2002/2003DISASTERS, Issue 4 2004Andre Griekspoor The southern Africa crisis represents the first widespread emergency in a region with a mature HIV/AIDS epidemic. It provides a steep learning curve for the international humanitarian system in understanding and responding to the complex interactions between the epidemic and the causes and the effects of this crisis. It also provoked much debate about the severity and causes of this emergency, and the appropriateness of the response by the humanitarian community. The authors argue that the over-emphasis on food aid delivery occurred at the expense of other public health interventions, particularly preventative and curative health services. Health service needs were not sufficiently addressed despite the early recognition that ill-health related to HIV/AIDS was a major vulnerability factor. This neglect occurred because analytical frameworks were too narrowly focused on food security, and large-scale support to health service delivery was seen as a long-term developmental issue that could not easily be dealt with by short-term humanitarian action. Furthermore, there were insufficient countrywide data on acute malnutrition, mortality rates and performance of the public health system to make better-balanced evidence-based decisions. In this crisis, humanitarian organisations providing health services could not assume their traditional roles of short-term assistance in a limited geographical area until the governing authorities resume their responsibilities. However, relegating health service delivery as a long-term developmental issue is not acceptable. Improved multisectoral analytical frameworks that include a multidisciplinary team are needed to ensure all aspects of public health are dealt with in similar future emergencies. Humanitarian organisations must advocate for improved delivery and access to health services in this region. They can target limited geographical areas with high mortality and acute malnutrition rates to deliver their services. Finally, to address the underlying problem of the health sector gap, a long-term strategy to ensure improved and sustainable health sector performance can only be accomplished with truly adequate resources. This will require renewed efforts on part of governments, donors and the international community. Public health interventions, complementing those addressing food insecurity, were and are still needed to reduce the impact of the crisis, and to allow people to re-establish their livelihoods. These will increase the population's resilience to prevent or mitigate future disasters. [source] Open versus laparoscopic resection for liver tumoursHPB, Issue 6 2009Thomas Van Gulik Abstract Background:, The issue under debate is whether laparoscopic liver resections for malignant tumours produce outcomes which are comparable with conventional, open liver resections. Methods:, Literature review on liver resection and laparoscopy. Results:, There are no randomized controlled trials (RCTs) published that provide any evidence for the benefits of laparoscopic liver resections for liver tumours. In case,control series reporting short-term outcomes, laparoscopic liver resection has been shown to have the advantage of a reduced length of hospital stay. There are as yet, however, no adequate long-term survival studies demonstrating that laparoscopic liver resection is oncologically equivalent to open resection. Discussion:, The challenge for the near future is to test the oncological integrity of laparoscopic liver resection in controlled trials in the same way that we have learned from the RCTs carried out in laparoscopic resection for colorectal cancer. It is likely that laparoscopic liver resection will then have to compete with fast-track, open liver resection. Already, concerns have been raised regarding the learning curve required to master the techniques of laparoscopic liver resection. [source] Robotic-assisted laparoscopic radical prostatectomy: Learning curve of first 100 casesINTERNATIONAL JOURNAL OF UROLOGY, Issue 7 2010Yen Chuan Ou Objective: Robotic-assisted laparoscopic radical prostatectomy (RALP) is gaining popularity for treating localized prostate cancer. We aimed to analyze the learning curve of a single surgeon using RALP in Taiwan. Methods: Medical records of 100 consecutive patients who underwent RALP were retrospectively reviewed. Preoperative, perioperative and postoperative parameters between patients in the first 30 cases (Group I), the second 30 cases (Group II) and cases 61,100 (Group III) undergoing RALP were analyzed. Results: Console time was shorter and blood loss was reduced in Groups II and III compared with Group I. Significant differences were found in vesicourethral anastomosis time (46.38 min for Group I vs 31.0 min for Group II vs 27 min for Group III, P < 0.01). Postoperative stay became statistically significantly shorter, from 7.33 days for Group I to 3.93 days for Group II to 3.0 days for Group III. Positive surgical margin of pT2 was reduced (13.3% for Group I, 7.1% for Group II and 0% for Group III) but not of pT3 (86.7% for Group I, 75% for Group II and 62.9% for Group III). Continence rate at 3 months was higher in Groups II (95%) and III (96.6%) than in Group 1 (76.7%, P < 0.05). Conclusions: For every 30 cases of RALP, vesicourethral anastomosis time and postoperative stay were significantly shorter. However, the incidence of surgical margin in pT3 prostate cancer was not significantly reduced. A learning curve of more than 100 cases is required to decrease the positive surgical margin in pT3 tumors. [source] Clinical outcomes and learning curve of a laparoscopic adrenalectomy in 103 consecutive cases at a single instituteINTERNATIONAL JOURNAL OF UROLOGY, Issue 6 2006MASATOSHI ETO Objective:, We examined the clinical outcomes and the learning curve for a laparoscopic adrenalectomy (LA) in 103 consecutive cases performed by three surgeons at our institute, according to the type of adrenal disorder. Patients and Methods:, One hundred and three patients with adrenal tumors, including 38 cases of primary aldosteronism, 33 cases of Cushing syndrome (including preclinical Cushing syndrome), 15 cases of pheochromocytoma, and nine cases of non-functioning adenoma were evaluated, while focusing on the approaches, intraoperative and postoperative data, and the learning curve of LA, according the type of adrenal disorder. Results:, There was no significant difference in the operation time, estimated blood loss, incidence of conversion to open surgery and blood transfusion, or postoperative recovery among the patients treated by LA for aldosteronoma, Cushing adenoma, pheochromocytoma, and non-functioning adenoma. In the cases of aldosteronoma and Cushing adenoma, the learning curve for the operation time and blood loss in each operator tended to decrease as the number of operations increased. On the other hand, in the cases treated by LA for pheochromocytoma, no trends in either the operation time or blood loss were observed. However, there has been neither any conversion to open surgery nor blood transfusion in cases treated by LA since 1998 (our 42nd case), even after the changes in the operators. Conclusions:, Our results clearly indicate that LA is becoming safer than before, probably due to improvements in the technique, education, and training of surgeons, in addition to the increased number of cases now treated by LA. [source] Complications and the learning curve for a laparoscopic nephrectomy at a single institutionINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2006TORU KANNO Background:, We assessed our experiences in performing a laparoscopic nephrectomy, with regard to complications and the learning curve, during a 4-year period. Methods:, Between November 2000 and October 2004, a total of 78 laparoscopic nephrectomies were performed at our institution (37 radical nephrectomies, 30 nephroureterectomies and 11 simple nephrectomies). The patient charts were retrospectively reviewed to identify any operative and postoperative complications, and also to evaluate the operating time. Results:, A total of eleven complications (14.1%) occurred in our series (nine operative and two postoperative complications). All operative complications were due to vascular injuries (n = 9), five (2.6%) of which required an open conversion. The operating time and the rates of complications decreased significantly as the surgeons' experiences increased. Conclusion:, A laparoscopic nephrectomy could be performed as safely as previously reported. In addition, the learning curve for a laparoscopic nephrectomy appeared to be good over the initial 50 procedures at our institution. [source] Radical retropubic prostatectomy through a minimal incision with portless endoscopy: Our initial experienceINTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2006HIDEO KIYOKAWA Abstract, Twenty-one patients with clinically localized prostate cancer underwent minilaparotomy radical retropubic prostatectomy through a single 5-cm midline or Pfannenstiel incision. A 30° laparoscope was usually positioned around the edge of the incision to facilitate the procedure. The mean operating time was 255 min. The mean blood loss was 859 mL, and no patient required an allogenic blood transfusion. Postoperative pain was noticeably reduced, especially in the Pfannenstiel incision group. Endoscope-assisted minilaparotomy did not involve a learning curve, and could be useful for most urologic surgeons as minimally invasive surgery. [source] Learning curve of hand-assisted retroperitoneoscopic nephrectomy in less-experienced laparoscopic surgeonsINTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2005AKIHIRO KAWAUCHI Abstract Aim:, To evaluate the learning curve of hand-assisted retroperitoneoscopic nephrectomy (HALS) performed by less-experienced surgeons. Methods:, The operative records of 166 patients, including 103 with renal tumors and 63 with renal pelvic or ureteral tumors, who underwent HALS performed by 18 less-experienced urologists were reviewed. Results:, The insufflation time in the first four cases was significantly longer than that in the sixteenth and later cases. The insufflation time in cases 5,10 was 14,24 min longer than that in the cases 16 onward, although the differences were not significant. The estimated blood loss did not differ in each group of cases. The complication rate in early cases, in which the operators' experience was five cases or less, was 6% (4/71), while that in later cases was also 7% (7/95). In the analysis of the learning curve of a single surgeon who performed 57 procedures, the insufflation time in cases 1,5 was significantly longer than in cases 41,57. The insufflation times in cases 5,10 were 45 min longer than those in cases 41,57, although the difference was not significant. The estimated blood loss did not differ in each group of cases. Complications did not seem related to operation experience. Conclusion:, In HALS, 5,10 cases were necessary for less-experienced urologists to gain average operating skills for this procedure. It may be reasonable for less-experienced surgeons to begin standard laparoscopic procedures after experiencing 10 cases of the present procedure. [source] Endoscopic Versus Conventional Radial Artery Harvest,Is Smaller Better?JOURNAL OF CARDIAC SURGERY, Issue 4 2006Oz M. Shapira M.D. Methods: Data were prospectively collected on 108 consecutive patients undergoing isolated CABG with ERH, and compared to 120 patients having conventional harvest (CH). Follow-up was achieved in 227 patients (99%). At the time of follow-up the severity of motor and sensory symptoms, as well as cosmetic result in the harvest forearm, were subjectively graded using a 5-point scale. Grade 1,high intensity deficits, poor cosmetic result. Grade 5,no deficits, excellent cosmetic result. Results: Hospital mortality, myocardial infarction, and stroke rates were similar between the groups. Follow-up mortality, reintervention rate, and average angina class were also similar. Harvest time was longer in the ERH group (61 ± 24 min vs. 45 ± 11 min, p < 0.001). Three patients in the ERH group were converted to CH and one radial artery was discarded. There were no vascular complications of the hand in either group. Average score of motor (ERH 4.4 ± 0.9, CH 4.2 ± 1.0) or sensory symptoms (ERH 3.7 ± 1.1, CH 3.8 ± 1.2) were similar. In the CH group sensory deficits were observed in the distribution of both the lateral antebrachial cutaneous and the superficial radial nerves (SRN). In contrast, sensory deficits in the ERH group were limited to the distribution of the SRN. Cosmetic result score was higher in the ERH group (ERH 4.2 ± 1.0, CH 3.1 ± 1.4, p < 0.0001). Conclusions: ERH is safe. It is technically demanding with a significant learning curve. Motor and sensory symptoms are not completely eliminated by using a smaller incision, but cosmetic results are clearly superior. [source] Robotic Surgery Using ZeusÔ MicroWristÔ TechnologyJOURNAL OF CARDIAC SURGERY, Issue 1 2003The Next Generation Methods: We used the ZeusÔ (Computer Motion Inc., Goleta, Calif, USA) telemanipulation system to perform the internal mammary artery (IMA) takedown in 56 patients, in 12 of whom we used the newest model with MicroWristÔ (Computer Motion Inc., Goleta, Calif, USA) technology. Port orientation was based on thoracic anatomy, the decisive landmarks being the mammillary line and the axillary line. The distance between ports was at least 9 cm, and the patient's arm was positioned with the left shoulder raised and angulated by not more than 90 degrees. Results: Mean setup time was 44 ± 18 minutes for the first five patients and 16 ± 7 minutes for the last five patients, with an overall average of 24 ± 12 minutes. IMA harvest time at the beginning reached a mean of 95 ± 23 minutes and decreased to 44 ± 18 minutes in the last five cases. Average IMA takedown time was 58 ± 17 minutes. The IMA was patent with a good flow in all 56 patients. Conclusions: The introduction of robotic technology into clinical routine has resulted in safe procedures with a short learning curve. However, basic training in the modality is a must in order to achieve technical excellence. (J Card Surg 2003; 18:1-5) [source] Validation of Computed Tomography Image Integration into the EnSite NavX Mapping System to Perform Catheter Ablation of Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2008LAURA RICHMOND R.N., M.Sc. Introduction: The complex anatomy of the left atrium (LA) makes location of ablation catheters difficult using fluoroscopy alone, and therefore 3D mapping systems are now routinely used. We describe the integration of a CT image into the EnSite NavX System with Fusion and its validation in patients undergoing atrial fibrillation (AF) or left atrial tachycardia (AT) catheter ablation. Methods and Results: Twenty-three patients (61 ± 9.2 years, 16 male) with paroxysmal (14) and persistent (8) AF and persistent (1) AT underwent ablation using CT image integration into the EnSite NavX mapping system with the EnSite Fusion Dynamic Registration software module. In all cases, segmentation of the CT data was accomplished using the EnSite Verismo segmentation tool, although repeat segmentation attempts were required in seven cases. The CT was registered with the NavX-created geometry using an average of 24 user-defined fiducial pairs (range 9 to 48). The average distance from NavX-measured lesion positions to the CT surface was 3.2 ± 0.9 mm (median 2.4 mm). A large, automated, retrospective test using registrations with random subsets of each patient's fiducial pairs showed this average distance decreasing as the number of fiducial pairs increased, although the improvement ceased to be significant beyond 15 pairs. In confirmation, those studies which had used 16 or more pairs had a smaller average lesion-to-surface distance (2.9 ± 0.7 mm) than those using 15 or fewer (4.3 ± 0.8 mm, P < 0.02). Finally, for the 13 patients who underwent left atrial circumferential ablation (LACA), there was no significant difference between the circumference computed using NavX-measured positions and CT surface positions for either the left pulmonary veins (178 ± 64 vs. 177 ± 60 mm; P = 0.81) or the right pulmonary veins (218 ± 86 vs. 207 ± 81 mm; P = 0.08). Conclusion: CT image integration into the EnSite NavX Fusion system was successful in all patients undergoing catheter ablation. A learning curve exists for the Verismo segmentation tool; but once the 3D model was created, the registration process was easily accomplished, with a registration error that is comparable with registration errors using other mapping systems with CT image integration. All patients went on to have subsequent successful ablation procedures. Where LACA was performed (13 patients), only four patients required segmental ostial lesions to achieve electrical isolation. [source] Single-Center Experience with the HelexÔ Septal Occluder for Closure of Atrial Septal Defects in ChildrenJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2003ROBERT N. VINCENT M.D. Catheter closure of atrial septal defects (ASDs) is an accepted procedure among pediatric cardiologists. We report our early experience with the newest of these devices in clinical trials in the United States. Between April and October 2001, 14 patients were enrolled in an FDA phase II multicenter trial comparing the results of ASD closure using the HELEXÔ Septal Occluder to a surgical control group. Of the 14 patients, devices were placed and left in 13, one being removed for an excessive residual leak despite placing the largest device available. Of the remaining 13 patients, all patients had successful closure of their defects. An average of 1.8 devices/patient were deployed, reflecting the learning curve for this new device and new delivery style. Six devices were replaced because of excessive residual leaks, three for premature lock release, and two for improper seating of the device. There were no procedural complications, however, one patient required device removal 4 months postimplant for possible allergic reaction to nickel. The same patient had removal of stainless steel sternal wires for the same reason. At the 6-month follow-up, 11 of 13 patients had complete closure of the ASD, the other two having small, hemodynamically insignificant left to right shunts. In one of these patients, there was complete closure at the 12-month follow-up, whereas the other patient awaits the 1-year evaluation. Early experience at our institution has demonstrated the ease of use of this device, its complete retrievability, and excellent closure of small to moderate ASDs in children. (J Interven Cardiol 2003;16:79,82) [source] Indications and patient selection for cytoreductive surgery and perioperative intraperitoneal chemotherapy,JOURNAL OF SURGICAL ONCOLOGY, Issue 4 2009Santiago González-Moreno MD Abstract Cytoreductive surgery combined with perioperative intraperitoneal chemotherapy has provided unprecedented results in the management of peritoneal-based neoplasms. Prognostic factors leading to a survival advantage when this treatment modality is employed have been identified. A steep learning curve has been described as well. Therefore, knowledgeable indication setting and proper selection of patients to whom this combined treatment can be offered is warranted in order to obtain the best results at the lowest possible toxicity. J. Surg. Oncol. 2009;100:287,292. © 2009 Wiley-Liss, Inc. [source] Learning curve in cytoreductive surgery and hyperthermic intraperitoneal chemotherapyJOURNAL OF SURGICAL ONCOLOGY, Issue 4 2009Bijan N. Moradi III MS Abstract Cytoreductive surgery and Hyperthermic Intraperitoneal Chemotherapy have achieved good long-term results in patients with complete surgical eradication of their peritoneal dissemination but at the expense of significant perioperative morbidity and mortality. The high complication rate has been attributed to the steep learning curve associated with this procedure. We report on the current literature regarding the learning curve for this procedure and the key components that determine the success in learning this new skill. J. Surg. Oncol. 2009;100:293,296. © 2009 Wiley-Liss, Inc. [source] Interpectoral approach to dissection of the Axillary Apex: An elegant and effective approachJOURNAL OF SURGICAL ONCOLOGY, Issue 3 2006Ajit Pai MS Abstract Background Axillary dissection is the goldstandard for treatment of the axilla. It provides important prognostic information, accurately stages the axilla, and has the lowest recurrence rate among all modalities. In today's age of conservation surgery, the axilla is often addressed through a cosmetically acceptable small incision with limited access, thereby making clearance of the level III nodes difficult. Methods We describe a method of apical lymph node dissection through the interpectoral plane, which effectively clears the apex despite the constraints of limited exposure. Results This method has been used in nearly 5,000 axillary dissections performed at our institute, with excellent results. It preserves the innervation of the pectoral muscles and affords access to the interpectoral nodes. Conclusions Our method has a short learning curve, provides good exposure of a difficult area and consistently provides a good yield of nodes. J. Surg. Oncol. 2006;94:252,254. © 2006 Wiley-Liss, Inc. [source] Laparoscopy-assisted distal gastrectomy with systemic lymph node dissection: A phase II study following the learning curveJOURNAL OF SURGICAL ONCOLOGY, Issue 1 2005Michitaka Fujiwara MD Abstract Background and Objectives A preliminary study on the use of laparoscopy-assisted approach to treat gastric carcinoma resulted in higher morbidity. Study Design A prospective phase II study of laparoscopy-assisted distal gastrectomy (LADG) was performed for patients with preoperative diagnosis of T1 N0 stage cancer located in the lower or middle-third stomach. Bleeding amount, operating time, mortality, morbidity, and the number of lymph node retrieval were recorded and compared with the preliminary series reported previously by the same authors. Results Between 2000 and 2002, 47 patients were accrued. The mean blood loss and postoperative hospital stay were significantly decreased compared with the previous series, whereas the operating time was not. There were no in-hospital deaths, with the incidence of anastomotic leakage significantly decreased. All patients remain disease-free to date. Conclusions LADG can be performed safely and morbidity, no longer, is a drawback by experienced hands that have reached plateau of the learning curve, although it remains a time-consuming procedure. Its application to gastric cancer surgery is feasible for early stage cancer, and its applicability to the treatment of T2 stage cancer will be the next issue to be explored. J. Surg. Oncol. 2005;91:26,32. © 2005 Wiley-Liss, Inc. [source] The Learning Curve of Resident Physicians Using Emergency Ultrasonography for Obstructive UropathyACADEMIC EMERGENCY MEDICINE, Issue 9 2010Timothy B. Jang MD Abstract Background:, Given the time, expense, and radiation exposure associated with computed tomography (CT), ultrasonography (US) is considered an alternative imaging study that could expedite patient care in patients with suspected obstructive uropathy. However, there is a paucity of literature regarding bedside US for obstructive uropathy in the emergency department (ED), and it is unknown how much experience is required for competency in such exams. Objectives:, The objective was to assess the learning curve for the detection of obstructive uropathy of resident physicians training in ED bedside US (EUS) during a dedicated EUS elective. Methods:, This was a prospective cohort study of residents participating in an EUS elective. Patients presenting with acute abdominal or flank pain suggestive of an obstructive uropathy were enrolled and underwent EUS prior to noncontrast CT. Physicians who had previously performed at least 10 EUS exams for obstructive uropathy recorded results on a standardized data sheet, which was subsequently compared to the results of noncontrast CT read by board-certified radiologists blinded to the results of the EUS. In addition to an unadjusted chi-square test for trend, a multivariable logistic regression analysis, adjusting for stone size and operator, was performed. Finally, generalized estimating equations were used to describe test characteristics while accounting for potential clustering between exams by operator. Results:, Twenty-three resident physicians participated and enrolled a convenience sample of 393 patients. A total of 157 patients (40%) were diagnosed with an obstructing ureterolith, and three (1%) were diagnosed with nonobstructing ureterolithiasis. An unadjusted chi-square test for trend demonstrated a statistically significant increase in both sensitivity (,2 = 11.4, p = 0.02) and specificity (,2 = 6.4, p = 0.04) for each level of increase in number of exams. On multivariable regression analysis, when adjusting for size of stone and operator, for every five additional exams after the first 10 EUS exams, the odds ratio for a true positive for obstruction increased by 1.7 (95% confidence interval [CI] = 1.2 to 2.5, p = 0.003). After accounting for clustering of exams by operator, overall EUS sensitivity and specificity for obstructive uropathy were 82% (95% CI = 77% to 87%) and 88% (95% CI = 85% to 92%). Stratifying by number of exams, the sensitivity was 72% (95% CI = 62% to 80%) for the 11th through 20th exams, 90% (95% CI = 83% to 96%) for the 21st through 30th exams, and 95% (95% CI = 91% to 99%) for the 31st through 43rd exams. Likewise, specificity was 82% (95% CI = 75% to 89%) for the 11th through 20th exams, 90% (95% CI = 85% to 95%) for the 21st through 30th exams, and 92% (95% CI = 86% to 98%) for the 31st through 50th exams. Conclusions:, Physicians training in EUS may be able to accurately assess for obstructive uropathy after 30 exams. ACADEMIC EMERGENCY MEDICINE 2010; 17:1024,1027 © 2010 by the Society for Academic Emergency Medicine [source] Early Results of Photoselective Vaporization of the Prostate in Medical Control-failed PatientsLUTS, Issue 2 2009Shen Kuang CHANG Objectives: We present here our early results and learning curve for photoselective vaporization of the prostate (PVP) performed by an experienced urologist and we provide an analysis of the morbidity and early functional outcomes. Methods: Forty-four patients were selected, from May 2006 to January 2009, who had benign prostate hyperplasia (BPH) accompanied by lower urinary tract symptoms (LUTS). After undergoing PVP for BPH at our hospital, the patients were followed up for approximately 2 years. PVP was performed by the same experienced urologist using potassium-titanyl-phosphate (KTP) laser. Baseline characteristics, preoperative and perioperative data, and postoperative complications were evaluated. Regular outpatient department follow-up was conducted after patients were discharged from the hospital at 1, 4 and 12 weeks. Results: The mean age of the 44 patients was 71.6 years. The mean prostate volume was 47.52 mL. The mean PVP surgery time was 79.11 min. The mean urinary catheterization time was 23.41 h. Few complications arose after PVP, except that 47.7% of the patients developed pyuria after being discharged from hospital. The average hospital stay was 2.45 days. There were no significant differences in the efficiency of tissue vaporization among the patients. Conclusion: PVP for BPH has various advantages, including reducing postoperative complications. An experienced urologist can easily perform PVP. However, early results show no significant differences in the efficiency for the PVP technique. [source] Training program and learning curve in experimental microsurgery during the residency in plastic surgeryMICROSURGERY, Issue 4 2007Ioan Lascar M.D., Ph.D. This article presents a comparison of microsurgical training of groups with different background. A protocol based on the rat femoral arterial anastomoses was used to provide an objective representation of the microsurgical skills progress. The performance is assessed by consistent (×4) patency of a standardized anastomosis. Three groups of beginner residents with progressive microsurgical experience and one group of experienced surgeons were observed. The patency curve of the beginner-groups was as an abrupt learning curve, and then a plateau was reached. There was no statistically significant difference in the patency rate between the beginner-groups after their first 32 anastomoses. No statistically significant difference was noted when the patency of the advanced group was compared with beginner-groups after different numbers of anastomoses (inverse proportional with their training experience). A slight or a plateau learning curve was found among the experienced group. The learning curve is a useful adjunct in the assessment of training. © 2007 Wiley-Liss, Inc. Microsurgery 2007. [source] Linear Ablation with Duty-Cycled Radiofrequency Energy at the Cavotricuspid IsthmusPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 4 2010STEFANIE BOLL Background: Multielectrode catheters using duty-cycled radiofrequency (RF) have been developed to treat atrial fibrillation (AF). Many of these patients also have atrial flutter. Therefore, a linear multielectrode has been developed using the same RF energy. Objective: The concept and acute results of linear ablation using duty-cycled RF were tested in the cavotricuspid isthmus (CTI). Methods: The CTI was targeted in 75 patients, in 68 (90%) among them as an adjunct to AF ablation with the same technology. A linear electrode catheter with a 4-mm tip and five 2-mm ring electrodes was connected to a generator titrating duty-cycled RF at 20,45 W up to a target temperature of 70°C in 1:1 unipolar/bipolar mode. Results: During a mean procedure time of 20 ± 12 minutes, complete CTI block was achieved by 4 ± 3 applications of duty-cycled RF in 69 (92%) patients. No more than three RF applications were necessary in 60% of patients. During the initial learning curve, standard RF had to be used in five (7%) patients. Complete block was not achieved in one patient with frequent episodes of AF. Char was observed in five (7%) patients with poor electrode cooling; consequently, the temperature ramp-up was slowed and manually turned off in the event of low-power delivery. Two groin hematomas occurred; otherwise, no clinical complications were observed. Conclusion: Multielectrode catheters delivering duty-cycled RF can effectively ablate the CTI with few RF applications with promising acute results. Further modifications are necessary to improve catheter steering and prevent char formation. (PACE 2010; 444,450) [source] Child protection: crisis management or learning curve?PUBLIC POLICY RESEARCH, Issue 4 2008Ruth Gardner As the media portrays England's child protection system as being in dire straits, Ruth Gardner and Marian Brandon state the case for concentrating resources on improving the amount and quality of contact that professionals have with children and their parents [source] | |||||||||||||||||||||||||||||||||||||||||||