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3D-visualization improves the dry-lab coronary anastomoses using the Zeus robotic system.

BACKGROUND: Robotic surgical instruments enable quick and precise movements and may allow complete endoscopic coronary artery bypass grafting. However, cardiac surgeons will have to become familiar with this technology and endoscopic viewing. We present our training program with special focus on 2D- and 3D-visualization. METHODS: A thoracic skeleton, covered with a neoprene suit, served as model for the chest wall. Either a glove, fixed on a metal plate, or a pig heart were placed inside for training. On the glove, a suture line consisting of two lines of 16 points each, with a distance of 2 mm between each point, was stamped. On the pig heart, the LAD was prepared and incised; subsequently an anastomosis was done using the dissected right coronary artery as a graft. The time required was measured for both models. For suturing, the Zeus System (Computer Motion, Goleta, CA) was used and the third robotic arm positioned the endoscopic camera. The scopes were connected to a 3D-camera and the picture was displayed on a headset with two integrated monitors. Visualization was set to either 2D or 3D. Three surgeons were involved in the study. Each one did at least 12 anastomoses on 2D and 3D. RESULTS: The three surgeons involved showed a clear and rapid learning curve. The times required for the suture line decreased from 12.5 +/- 1.6 to 8.5 +/- 0.5 minutes with 2D and from 11.9 +/- 5.4 to 7.8 +/- 0.5 minutes for 3D respectively. This decrease did reach statistical significance (p = 0.03). In the pig heart model, the anastomosis times decreased from 33.2 +/- 8.4 to 15.7 +/- 0.3 minutes with 3D-visualization, and from 36.2 +/- 2.2 to 29.5 +/- 3.3 minutes with 2D. The decrease in anastomosis time did again reach significance (p = 0.025). At the end of the study, the times achieved with 2D-visualization were significantly longer than those with 3D (p = 0.01). CONCLUSIONS: A surgical training program is mandatory to become familiar with these new technologies. Both models showed learning curves over an acceptable time course. 3D-visualization facilitated quick and precise movements, thus resulting in shorter anastomosis times.

Anastomosis, Surgical↗

Laparoscopic retroperitoneal lymph node dissection.

PURPOSE: Retroperitoneal lymph node dissection is the most sensitive and specific diagnostic modality for detecting occult lymph node metastases in clinical stage I testicular tumor. In stage II disease, residual tumors after chemotherapy have to be removed surgically. To reduce the morbidity of these procedures we have replaced open surgery by laparoscopy. PATIENTS AND METHODS: Between August 1992 and December 1999 125 patients underwent laparoscopic RPLND (stage I: 76 pts., stage II: 49 pts.) RESULTS: Laparoscopic RPLND could be completed as planned in all but two patients in whom bleeding required conversion to open surgery. Once the learning curve had been overcome, mean operative time decreased significantly from 476 to 219 min for stage I and averaged 226 min in stage IIB disease. Only minor postoperative complications occurred such as asymptomatic lymphoceles (7 pts.) and chylous ascites (6 pts.). Mean post-op hospital stay was 3.3 and 3.5 days, respectively (stages I and II). Mean followup is currently 46 months for stage I and 35 months for stage II tumors. Over this period a single retroperitoneal recurrence was observed (stage I), which, however, was not due to surgical failure, but to false negative histologic findings. All other patients have remained free of relapse. CONCLUSIONS: Laparoscopic RPLND is a demanding procedure with a long and steep learning curve. It has proved feasible also after chemotherapy. The diagnostic accuracy of laparoscopic RPLND was as good as that of the open procedure, while the morbidity is significantly lower. Tumor control was not compromised by the laparoscopic approach.

Adolescent↗

Complications of endoscopic neurosurgery.

Neuroendoscopy is rapidly becoming an essential part of the neurosurgeon's repertoire. Currently, very few studies have identified the complications of this new technique, yet many have warned of the steep learning curve associated with its practice. We have reviewed the last 173 neuroendoscopic procedures performed by one surgeon and identified two distinct groups of complications: those that have clinically significant sequelae and those that cause concern intraoperatively but no overt clinical problems. The 173 procedures were performed on 152 patients. Of these patients, 11 suffered significant complications (7%). Twenty-two of the procedures were complicated by intraoperative problems (13%). The incidence of insignificant complications appeared to decrease with experience, whereas that of the significant ones did not. These complications occurred in association with a wide variety of operations over a 2-year period. We conclude that neuroendoscopy is a relatively safe technique with an overall 7% complication rate and a steep learning curve, and that, with a few simple guidelines, it can be employed by all neurosurgeons for the betterment of their patients.

Adolescent↗

Scorecard endoscopy: a pilot study to assess basic skills in trainees for upper gastrointestinal endoscopy.

BACKGROUND: The development of training models and structured training courses for endoscopic techniques provides practical experience. To assess individual performance and progress in this training we developed and tested a scorecard system. METHODS: Three test groups were compared: group 1, ten physicians without previous endoscopic experience; group 2, ten students, without endoscopic experience; group 3, a control group of experienced endoscopists. Groups 1 and 2 underwent 1 week of training with a theoretical introduction and practical demonstrations. They were assessed by the scorecard daily by an experienced tutor. The individual scores and learning curves of the two beginner groups were compared with those of the expert group using a biosimulation model was used. RESULTS: Each participant improved significantly during the 1-week course. Mean scores on the first day in groups 1-3 were, respectively, 26.7+/-10.7, 33.4+/-5.3, and 72.0+/-5.8, and on day 6 they were 62.2+/-6.6, 63.4+/-7.6, and 86.6+/-4.3. The difference between group 3 and the other two groups was significant but not that between groups 1 and 2. CONCLUSIONS: Training in endoscopy can be assessed using our training model and our scorecard protocol, which distinguishes between various levels of experience. In physicians beginning in the field of gastrointestinal endoscopy this approach could help to reduce risks to patients, shorten learning curves, and exclude unskilled individuals from further fruitless interventions.

Animals↗

Laparoscopic hysterectomy versus total abdominal hysterectomy: a comparative study.

OBJECTIVE: The objective of this study was to compare the intraoperative and short-term postoperative complications of laparoscopic hysterectomy and total abdominal hysterectomy. STUDY DESIGN: Retrospective study of 167 women who had laparoscopic hysterectomy and 119 women who had total abdominal hysterectomy. For assessing the learning curve, the laparoscopic hysterectomies were further subdivided to the first 30 hysterectomies and the later hysterectomies. For data analysis Student's t-test, chi2-test and Fisher's exact test were used. RESULTS: There were no statistically significant differences between the two groups for age, body mass index, previous abdominal surgery, uterine weight, first postoperative day hemoglobin drop, blood transfusion and major or minor complications rate. Operation time was significantly longer for laparoscopic than abdominal hysterectomy (156+/-40 and 91.2+/-33 min, respectively; P<0.001) but the length of hospital stay was significantly shorter (3.9 and 6.55 days, respectively; P<0.001). The conversion rate of laparoscopic hysterectomy was 1.8% (three cases). CONCLUSIONS: Laparoscopic hysterectomy can be safely done even during the learning curve with a low and reasonable complication rate, and a shorter hospital stay but with longer operation time. As experience is gained the operation time, complication rate and hospital stay are decreased.

Female↗

Is training in endoscopic carpal tunnel release appropriate for residents?

Based on the relatively high incidence of complications for surgeons initially learning the technique, endoscopic carpal tunnel release is thought to have a steep learning curve. To determine if endoscopic carpal tunnel release can be safely performed by trainees, the outcomes of 84 patients who underwent endoscopic carpal tunnel release performed by a chief resident or hand fellow in a supervised setting were reviewed. All but 1 patient had uneventful procedures and complete resolution of preoperative symptoms. One patient with persistent symptoms represented the only complication. At reexploration through a standard palmar incision, the transverse carpal ligament was found to have been completely divided and fulminant tenosynovitis surrounding the nerve and flexor tendons was presumed to be the cause of his persistent symptoms. It appears that endoscopic carpal tunnel release can be safely performed by chief residents in a supervised clinical setting. Given that this procedure has a high learning curve, repeated exposure during a residency training program may offer significant advantages over the current approach of training surgeons during a single cadaveric instructional course.

Cadaver↗

The role of sentinel lymph node biopsy in breast cancer.

BACKGROUND: Lymphatic mapping and sentinel lymph node (SLN) biopsy are new techniques that accurately provide crucial staging information while inflicting far less morbidity than complete axillary dissection. As these techniques continue to gain acceptance, issues such as adequacy of training, certification, and outcomes measures become increasingly important. The purpose of this paper is to report the initial lymphatic mapping experience at the H Lee Moffitt Cancer Center and Research Institute and to provide a detailed description of the technical aspects of lymphatic mapping. STUDY DESIGN: From April 1994 to April 1998, 700 patients with newly diagnosed breast cancers underwent an IRB-approved prospective trial of lymphatic mapping using a combination of Lymphazurin (USSC, Norwalk, CT) blue dye and filtered technetium 99m-labeled sulfur-colloid. Failure of the procedure was defined as the inability to detect an SLN by either radiocolloid uptake within a lymph node by the gamma probe or the inability to visualize blue staining of a lymph node. Learning curves were then generated as the failure rate versus serial number of patients for each of the 5 surgeons involved in this study. RESULTS: The SLN was identified in 665 of 700 patients (95.0%). A total of 1,348 SLNs were successfully removed, of which 238 (17.7%) were positive for metastatic disease in 176 of 665 patients (26.5%). In patients who underwent a complete axillary dissection after SLN biopsy, SLNs were identified in 173 of 186 patients (93.0%). Of the 173 patients, 53 patients (30.6%) had positive SLNs and 120 patients (69.4%) had negative SLNs. In the 120 patients with negative SLNs, one patient was found to have disease on complete dissection, for a false-negative rate of 0.83% (95% CI: 0.02%, 4.6%). A learning curve representing the mean of the 5 surgeons' experience indicates that on average 23 patients are required by an individual surgeon to achieve a 90% +/- 4.5% success rate and 53 patients are required to achieve a 95% +/- 2.3% success rate (p = 0.05). CONCLUSIONS: These data validate lymphatic mapping and SLN biopsy as indispensable tools in the surgical treatment of breast cancer. With adequate multidisciplinary training, these techniques can be readily implemented at institutions treating breast cancer.

Biopsy↗

[Sentinel lymphonodectomy in breast cancer - our own experience. Part 2].

UNLABELLED: The aim of this investigation was to document the personal learning curve of the sentinel lymphonodectomy in breast surgery and to compare it with the experiences of other authors. RESULTS: Between July 1999 and May 2004, the authors performed 218 sentinel lymphonodectomies, 48 of them during the 24-month evaluation period with consecutive full axillary dissection. The overall detection rate was 212/218 or 97.2%, while during the evaluation period it was 38/48 or 89.6% (failures were procedures No. 6, 7, 22, 24 and 47). Among the first 48 cases, 24 had histologically proven metastasis to one or more of the axillary lymph nodes. In 3 of these cases, we were not able to detect a sentinel lymph node, and 4 times the sentinel lymph node was false-negative after rapid section. The false-negative results during the learning period belonged to cases No. 2, 10, 23 and 29 (4/21 or 19%). From September 2001 until May 2004, the detection rate was over 99% (165/166). DISCUSSION: Our own experience documents the initial difficulties and insecurities with this operative procedure. The common recommendations, i.e. that sentinel lymphonodectomy without axillary clearance should not be offered before having completed one's own learning curve with the aid of experienced surgeons, are to be supported.

Axilla↗

Comparison of Colvard pupillometer and infrared digital photography for measurement of the dark-adapted pupil diameter.

PURPOSE: To investigate the accuracy of pupil diameter measurement using the Colvard pupillometer and to determine the learning curve for inexperienced examiners. SETTING: Texas Tech University Health Sciences Center, Lubbock, Texas, USA. METHODS: In this population study, subjects with normal pupillary behavior were tested by 1 of 2 investigators (examiner A, examiner B). After 5 minutes of dark adaptation at 1 lux, digital infrared pupil photography of the right eye was performed, followed by measurement of the horizontal pupil diameter and vertical pupil diameter with the Colvard pupillometer. The photographs were digitally analyzed to determine the horizontal and vertical pupil diameters. During phase I of the study, examiners were masked to the results of infrared pupil photography; during phase II, they reviewed the infrared pupil photography results after each testing session. Bland-Altman plots were created to detect measurement bias; results were graphed by subject test sequence to assess learning. A test difference of less than +/-0.5 mm was considered clinically acceptable. RESULTS: Fifty-nine subjects were tested in phase I, of whom 39 had adequate infrared pupil photography for analysis; 40 were tested in phase II, of whom 34 were included. The mean age of the analyzed subjects was 27 years (range 18 to 44 years). For all subjects, the infrared pupil photography median horizontal pupil diameter was 7.09 mm +/- 0.75 (SD) (range 5.44 to 8.79 mm); the median vertical pupil diameter was 7.22 +/- 0.79 mm (range 5.45 to 9.10 mm). Examiner A initially had a negative bias (Colvard pupillometer value less than infrared pupil photography value) for both horizontal and vertical pupil diameter measurements, which resolved during phase I after 23 subjects were tested; 18 of the final 19 subjects tested (11 phase I, 8 phase II) showed a test difference of less than 0.5 mm for all readings. The pupil diameter did not affect the bias. Examiner B had a strong positive bias that persisted throughout the study. Testing 26 subjects in 5 sessions during phase II did not improve the accuracy. During the final testing session, 3 of 8 subjects had a test difference of 0.5 mm or more in at least 1 dimension. The pupil diameter did not affect the bias. CONCLUSION: The Colvard pupillometer is susceptible to user errors causing unidirectional bias and seems to have a steep and variable learning curve.

Adolescent↗

Increase in the incidence of peritoneal collagen balls over a 10-year period.

OBJECTIVE: To describe the detection of collagen balls in peritoneal washings over a 10-year period, revealing an unexpected and unexplained higher incidence than in the past. STUDY DESIGN: Reports of routinely processed, Papanicolaou-stained smears and cytospins and hematoxylineosin-stained cell blocks from peritoneal washes and ascitic fluids seen over an 8-year period (1995-2002) were reviewed, and the percentage of specimens in which collagen balls were noted was determined. To rule out a learning curve phenomenon, the first 100 consecutive peritoneal washings and ascitic specimens from years 1993-2001 plus 2002 were rescreened, and the percentage of specimens containing collagen balls was determined. RESULTS: The percentages of cases with collagen balls increased steadily beginning with 8 of 467 cases (3.2%) in 1995 to 185 of 650 (28.5%) in 2002, as reported in the case records. Rescreened cases also showed a similar increase, 4.0% in 1993 to 29% in 2002. No procedural modifications were made in specimen processing during this interval, nor are we aware of any procedural change in obtaining cytologic samples. CONCLUSION: An unexplained 7-fold increase in the percentage of peritoneal samples with collagen balls occurred over a 10-year period. This increase cannot be attributed to changes in specimen handling or to a learning curve phenomenon. This finding is of unknown significance and may warrant further investigation.

Ascitic Fluid↗

Thoracoscopic versus laparoscopic modified Heller Myotomy for achalasia: efficacy and safety in 87 patients.

BACKGROUND: The ideal treatment for achalasia permanently eliminates the dysfunctional lower esophageal sphincter, relieving dysphagia and regurgitation; prevents gastroesophageal reflux; and has an acceptable morbidity rate. Controversy exists concerning whether the thoracoscopic Heller Myotomy (THM) or laparoscopic Heller myotomy (LHM) technique is the best approach to a modified Heller myotomy for achalasia. STUDY DESIGN: We performed a retrospective comparison of the patient characteristics, operative results, postoperative symptoms, and the learning curves for the procedures of 24 patients undergoing THM and 63 patients undergoing LHM between 1991 and 1998. RESULTS: Preoperative patient variables in each group revealed similar distributions for age, gender, and prevalence of previous pneumatic dilation. Mean operating room (OR) times were 4.3 hours (range 2.9 to 5.6 hours) for THM and 3.0 hours (range 1.5 to 6.5 hours) for LHM (p = 0.01). Three esophageal perforations occurred in the THM group and two in the LHM group. Conversion to an open procedure took place in five THM operations (21%) and one LHM operation (2%) (p = 0.005). There were no postoperative esophageal leaks. Mean postoperative length of stay (LOS) for THM was 6.1 days (range 1 to 17 days) and for LHM was 4.0 days (range 1 to 12 days) (p = 0.03). Learning-curve analysis of the first 24 LHM patients compared with the most recent 24 revealed greater OR time in the first 24 mean 3.6 hours, (range 2.0 to 6.5 hours) versus mean 2.3 hours, (range 1.5 to 3.7 hours; p = 0.01), and greater LOS mean 5.5 days, (range 3 to 12 days) versus mean 3.1 days, (range 1 to 8 days; p < 0.01). One esophageal perforation occurred in each subgroup. A similar analysis in the first 12 THM patients compared with the most recent 12 revealed no significant improvement in OR times or LOS. Three esophageal perforations occurred in the latter subgroup only. All patients had preoperative daily dysphagia to solids. Followup data for LHM (n = 49) (median 17 months, range 1 to 39 months) and THM (n = 15) (median 42 months, range 1 to 69 months) revealed no or minimal dysphagia in 90% (44 of 49) after LHM and 31% (4 of 13) after THM (p < 0.01). No or minimal heartburn was present in 89% (41 of 46) after LHM and 67% (8 of 12) after THM (p < 0.05). Regurgitation was absent or minimal in 94% (46 of 49) after LHM and 86% (12 of 14) after THM (p = 0.3). CONCLUSIONS: LHM was associated with decreased OR time, decreased rate of conversion to an open procedure, and shorter LOS compared with THM. LHM was superior to THM in relieving dysphagia and preventing heartburn. LHM may be the preferred surgical treatment of achalasia in some patients.

Adolescent↗

[Hand-assisted laparoscopy].

OBJECTIVES: Laparoscopic surgery has not been extended enough among the urologists due to the inaccessibility of the retroperitoneal organs and consequently to the steep learning curve that is required. In this article we describe our experience in laparoscopic surgery assisted by the surgeon's hand introduced in the operating field. This is a technique that we have been using since 1994 and that has not been generally accepted until very recently. METHODS: Difficult nephrectomies and nephroureterectomies are considered to be the main indications for this technique. The approach to each kidney is described. RESULTS: The operating time is dramatically reduced. The surgeon's hand introduced intra-abdominally allows for a better control in difficult situations. The economic cost is lower. The use of analgesics and the recovery time in the postoperative period is similar to that of conventional laparoscopy. CONCLUSIONS: The optimal indication for this procedure are cases that require a very large and mutilating incision. The learning curve is significantly easier and it is an invaluable technique in cases considered until now to be unsuitable for an endoscopic procedure.

Humans↗

Safety and efficacy of laparoscopic cholecystectomy. A prospective analysis of 100 initial patients.

Laparoscopic cholecystectomy quickly emerged as an alternative to open cholecystectomy. However its safety, efficacy, and morbidity have yet to be fully evaluated. During the first 6 months of 1990, we performed 100 consecutive laparoscopic cholecystectomies with no deaths and a morbidity rate of 8% (8 of 100 patients; 4 major, 4 minor). There were 81 women and 19 men, with a mean age of 46.1 years (range, 17 to 84 years). All patients had a preoperative history consistent with symptomatic biliary tract disease, and most had proved gallstones by sonography. This included four patients with acute cholecystitis. Mean operating time improved significantly from month 1 to month 6 (122 +/- 45.4 minutes versus 78.5 +/- 30 minutes, respectively), indicating a rapid learning curve. Mean hospital stay was 27.6 hours, reflecting a policy of overnight stay. Postoperative narcotic requirements were limited to oral or no medications in more than 70% of patients. A regular diet was tolerated by 83% of the patients by the morning following the procedure. Median time of return to full activity was 12.8 +/- 6.8 days after operation. In addition analysis of the hospital costs of these 100 cases demonstrates a modest cost advantage over standard open cholecystectomy (n = 58) (mean, $3620.25 +/- $1005.00 versus $4251.76 +/- $988.00). There was one minor bile duct injury requiring laparotomy and t-tube insertion, two postoperative bile collections, and one clinical diagnosis of a retained stone that passed spontaneously. Four patients required conversion to open cholecystectomy because of technical difficulties with the dissection. Although there is a significant learning curve, laparoscopic cholecystectomy is a safe and effective procedure that can be performed with minimal risk. Laparoscopic cholecystectomy should be performed by surgeons who are trained in biliary surgery and knowledgeable in biliary anatomy, and, as with all operations, it should be performed with meticulous attention to technique.

Adolescent↗

Repeatability and reproducibility of upper eyelid measurements.

AIM: The aim of this study was to assess the repeatability and reproducibility by physicians of upper lid measurements and to investigate the influence of clinical experience on the learning curve effect. METHODS: Both eyes of 22 outpatients were assessed for three basic measures of ptosis: marginal reflex distance (MRD) for upper and lower lids, upper lid skin crease (SC), and levator function (LF). Patients with variable eyelid positions were excluded. The patients were measured twice by a consultant and once by each of a clinical fellow, a specialist registrar, and a senior house officer in random order. Each observer was masked to their colleagues' results and followed a standard measurement protocol. Data were analysed using Bland-Altman plots. RESULTS: Consultant repeatability was high and consistent, the median difference between measures being 0 for each of the four parameters. Clinically acceptable reproducibility was shown in all measurements for even the least experienced physician and was particularly consistent for extreme observations. There was evidence of a learning curve effect. CONCLUSIONS: These results suggest that interobserver and intraobserver variability in assessment of upper lid ptosis using a standard measurement protocol is low and clinically acceptable when the technique of assessment is standardised.

Blepharoptosis↗

[Clinical evaluation of the dynamic rebound tonometer Icare].

PURPOSE: The Icare dynamic tonometer (impact or Rebound tonometry) is a new tonometer based on making a moving object collide with an eye and on monitoring the motion parameters of this object following contact. The purpose of this study was to assess intra- and interobserver variability of IOP measurements with the Icare and their correlations with Goldmann applanation tonometry (GAT) and central corneal thickness (CCT). MATERIAL AND METHODS: A prospective study including three groups of patients: group 1 (50 normal subjects), group 2 (50 patients with OHT or POAG and GAT IOP>22 mmHg), and group 3 (38 glaucomatous patients with GAT IOP< or =22 mmHg). In group 1, three consecutive IOP measurements were taken by three distinct observers with Icare followed by three GAT measurements by the same clinician. In group 2, the same procedure was followed from patients 1 to 25 and the reverse sequence from patients 25 to 50 after a 10-min break. In group 3, only one clinician took three GAT measurements followed by three Icare measurements after a 10-min break to exclude a tonographic effect in eyes with statistically normal-range IOPs. RESULTS: : In group 1, intraobserver variability was about 6% for each observer (NS). There was no learning curve effect. The interobserver variation coefficient was 6.4%. Icare overestimated IOP compared to GAT (mean difference, 1.5-2.2 mmHg) (p<0.001). Icare IOP was 23.4 mmHg for observer 1 when GAT was 22 mmHg (95% individual CI, 18-28.9 mmHg). In group 2, intraobserver variation coefficients of the IOP ranged from 5% to 5.4% (NS). Icare overestimated IOP by mean 0.84 mmHg compared with GAT. In group 3, mean IOP was not different between Icare and GAT. Icare IOP of 20.7 mmHg corresponded to a value of 22 mmHg using GAT. In this group, correlations between CCT and IOP measurements were higher for Icare than for GAT (p=0.062). CONCLUSION: Icare measures IOP in an unanesthetized sitting patient in a very brief time. Patient's minimal cooperation is needed. As long as the device is correctly positioned, the learning curve is short. Icare gives reproducible IOP measurements. Intra- and interobserver variability of IOP measurements are close to those of GAT. Icare overestimates IOP measurements an average 1.5 mmHg compared with GAT. Whatever the IOP level, Icare IOP measurements are well correlated with GAT. To a greater extent than for GAT, the reliability of IOP measurements is influenced by CCT. This tonometer can be used as a screening device for ocular hypertension as long as CCT measurements can be taken.

Equipment Design↗

Experience on the way to totally endoscopic atrial septal defect repair.

BACKGROUND: Remote-access perfusion and robotics have enabled totally endoscopic closure of atrial septal defect (ASD) and patent foramen ovale (PFO). We report on a stepwise approach to a totally endoscopic procedure. METHODS: Seventeen patients (median age, 39 years; range, 21-55 years) underwent limited-access ASD or PFO closure. As a preparative step, the operation was carried out through minithoracotomy in 11 patients. In parallel, experience with robotic surgery was gained with totally endoscopic coronary artery bypass grafting procedures. After performance of ASD closures in dry-laboratory models using the da Vinci telemanipulation system, 6 patients were operated on in a totally endoscopic fashion. RESULTS: With the endoscopic approach, significant learning curves were noted for cardiopulmonary bypass time y(min) = 226 - 41 * ln(x) (P = .03) and aortic cross-clamp time y(min) = 134 - 42 * ln(x) (P = .01) (x = number of procedures). There was no hospital mortality, and no residual shunts were detected at postoperative echocardiography. Median ventilation time was 9 hours (range, 0-18 hours) for the minithoracotomy group and 6 hours (range, 4-19 hours) for the totally endoscopic group. Median intensive care unit stay was 20 hours (range, 18-24 hours) and 18 hours (range, 18- 120 hours), respectively. CONCLUSIONS: The implementation of robotic totally endoscopic closure of ASD or PFO in a heart surgery program seems to be safe. An intermediate step of performing the operations through minithoracotomy, adapting to remote access perfusion systems, and gaining experience in other robotic cardiac surgical procedures seems worthwhile. Learning curves are apparent, and adequate defect closure does not seem to be compromised by the totally endoscopic approach.

Adult↗

Technology Insight: surgical robots--expensive toys or the future of urologic surgery?

There is an increasing demand for minimally invasive surgery, despite any controversy over whether patients benefit from minimally invasive procedures rather than undergoing open surgery. In the field of urology, the performance of more complicated procedures is still a challenge even for experienced laparoscopic surgeons. Recently, robots have been introduced to enhance operative performance, increase applicability and precision of laparoscopy, and improve the learning curve for complicated minimally invasive procedures. With the introduction of master-slave systems where the surgeon is seated remotely from the robot and uses controls to maneuver the mechanical arms placed inside the patient, a new development in robot-assisted surgery has commenced. Several authors have suggested that surgical robots similar to the da Vinci Surgical System (Intuitive Surgical, Sunnyvale, CA), which have three-dimensional (3D) vision and wristed instruments thus giving a greater degree of freedom than rigid laparoscopic instruments, will facilitate the outcome of these more challenging laparoscopic procedures. Whether these features will translate into better functional and oncological results remains to be evaluated. Data published so far clearly suggest that the patient will benefit from less postoperative pain, decreased bleeding and a shorter hospital stay compared with open surgery, and that the surgeon benefits from a faster learning curve than for conventional laparoscopy. For the benefit of our patients and for the development of urology it is vital that we understand both the limitations of telerobotics and when it is appropriate to incorporate these new techniques in day-to-day urologic surgery.

Costs and Cost Analysis↗

Incidence and management of intraoperative and early postoperative complications in 1000 consecutive laser in situ keratomileusis cases.

OBJECTIVE: To identify intraoperative and early postoperative complications of laser in situ keratomileusis (LASIK) surgery learning curve and to offer recommendations on prevention and management. DESIGN: Retrospective noncomparative case series. PARTICIPANTS: The first 1000 consecutive myopic LASIK eyes (April 1995-February 1997) operated on by one surgeon (HVG) were examined. INTERVENTION: Myopic LASIK surgery was performed with the Chiron Corneal Shaper and NIDEK EC-5000 excimer laser. MAIN OUTCOME MEASURES: The preoperative and 6-month postoperative spherical equivalent, best-corrected visual acuity, and corneal status were recorded, as was the incidence of intraoperative and early postoperative complications. The rate of retreatments was also recorded. RESULTS: There were 32 (3.2%) intraoperative complications and surgical events recorded, including 19 (1.9%) microkeratome-related flap complications and 13 (1.3%) nonmicrokeratome-related surgical events such as inability to obtain sufficient suction. There were 18 (1.8%) postoperative complications requiring repositioning of microwrinkled or shifted flaps. Six-month spherical equivalent was -0.52 diopter [D] +/- 1.19 D for eyes with microkeratome complications, -0.56 D +/- 1.07 D for the group with nonmicrokeratome-related intraoperative events, and -0.78 D +/- 0.92 for eyes requiring postoperative flap repositioning. None of the 32 eyes with intraoperative complications and surgical events lost 2 or more lines of vision. One eye in the postoperative complications group lost two lines of vision. The rate of microkeratome complications related to surgical technique and the overall surgery times decreased over the course of the first 1000 myopic LASIK cases. CONCLUSION: The complications encountered during the early learning curve of LASIK surgery have not in this series resulted in a significant loss of best-corrected visual acuity. With increasing surgical experience, the incidence of complications, along with surgical times, has decreased.

Adult↗