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PubMed2006

Evaluation of an intuitive writing interface in robot-aided laser laparoscopic surgery.

OBJECTIVE: The feasibility of the conceptual Intuitive Writing Interface (IWI) in robot-aided laser laparoscopic surgery has been demonstrated previously. This paper investigates the potential improvement of IWI by comparing conventional manipulation (CM) and IWI manipulation (IM) and conducting an animal experiment. MATERIALS AND METHODS: Three tasks were designed that were considered to be representative of laser laparoscopic surgical procedures. All test participants used both CM and IM in all tasks. Completion time and error level of each task were taken as comparative indices and were integrated into a self-defined Index of Time and Error (ITE). Six sequential in vitro trials were carried out to investigate learning curves. In addition, nephrectomy was performed on a rabbit by employing IWI in robot-aided laser laparoscopic surgery. RESULTS: The results showed significant advantages for IM, with shorter completion time, more successful shots, and smaller error length in the three tasks, as compared to CM. The learning curve showed a promising trend for IM. More than half of the participants performed better with IM. The animal model experiment demonstrated the clinical feasibility of IM, but at the same time revealed some limitations. CONCLUSIONS: The new IWI interface definitely improved laser laparoscopic procedures by taking advantage of familiar writing skills. With its flexibility of implementation and ease of use, IWI has clear potential for use in laser laparoscopic procedures.

Animals↗

PubMed2006

Basal forebrain amnesia: a case study.

OBJECTIVE: To provide new evidence of the existence of basal forebrain amnesia, as a different entity from hippocampal or diencephalic amnesia. BACKGROUND: Some authors consider that the characteristics of amnesia do not depend on lesion site, although others claim there are neuropsychologic differences between amnesias due to hippocampal, diencephalic, and basal forebrain lesions. As to the latter, literature is scarce and controversial. The opportunity to thoroughly study J.S., a man with a high IQ and amnesia, enabled us to reinforce the second hypothesis. METHODS: J.S. is a 47-year-old man who underwent surgery for a pituitary adenoma, the resulting lesion involving only the basal forebrain. We gave him a complete neuropsychologic battery for amnesia and executive functions. RESULTS: J.S. showed severe amnesia with a flat learning curve, a rapid forgetting rate and good recognition, a temporal gradient of several years for remote memory, preserved semantic and procedural memory. Most of the tests for executive functions were normal, although he did have a significant personality change after surgery. CONCLUSIONS: This patient is different from patients with hippocampal or diencephalic lesions, and is similar to other patients reported with basal forebrain lesions. The main difference is the relation between his flat learning curve and preserved recognition, both for visual and verbal material.

Adenoma↗

PubMed2003

Estimating dataset size requirements for classifying DNA microarray data.

A statistical methodology for estimating dataset size requirements for classifying microarray data using learning curves is introduced. The goal is to use existing classification results to estimate dataset size requirements for future classification experiments and to evaluate the gain in accuracy and significance of classifiers built with additional data. The method is based on fitting inverse power-law models to construct empirical learning curves. It also includes a permutation test procedure to assess the statistical significance of classification performance for a given dataset size. This procedure is applied to several molecular classification problems representing a broad spectrum of levels of complexity.

Algorithms↗

PubMed2004

Sentinel lymph node biopsy performed under local anesthesia is feasible.

BACKGROUND: A sentinel lymph node (SLN) biopsy in breast cancer patients, performed under local anesthesia (LA), could have advantages such as more efficient use of operating room time and pathologist time. It also provides a histologic diagnosis before definitive breast surgery is undertaken. The aim of this study was to assess feasibility by comparing the results of SLN procedures performed under LA versus general anesthesia (GA). METHODS: The SLN procedure was performed in 50 consecutive outpatients and 167 inpatients with clinical T1-2N0 breast cancer while they were under LA and GA, respectively. The SLN detection rate, a comparison of mapped and harvested SLNs, was compared for both groups. The duration of the SLN biopsies performed under LA was also measured. RESULTS: For both groups a median of 2 SLNs/patient were harvested. The detection rate was 1.00 for the LA group and 0.99 for the GA group. The learning curve for SLN procedures under LA showed a decrease in duration for the consecutive months (not significant). CONCLUSIONS: SLN biopsy can be safely and adequately performed with the patient under LA. It allows early diagnosis of the lymph node status, acquired on an outpatient basis, with minimal discomfort to the patient. The learning curve demonstrated that the LA procedure can quickly be mastered if the surgeon is experienced in performing SLN biopsies.

Ambulatory Surgical Procedures↗

PubMed2005

Investigation of training needs for functional endoscopic sinus surgery (FESS).

The use of simulators for training FESS may in the future offer substantial advantages like increased exposure to difficult scenarios, reduced learning curves, and reduced costs. Training simulators may range from very simple, involving only visual simulation, to more complex, involving haptic simulation or force feedback. To effectively employ these training means, insight is needed into the training needs for FESS procedure. A study was carried out to investigate which subtasks of FESS are hardest to perform and have the longest learning curve. A questionnaire was distributed among two groups of Ear, Nose and Throat (ENT) surgeons participating in a basic, as well as in an advanced sinus surgery course. Results showed that tasks related to spatial orientation are judged as hardest, whereas manual tasks are considered less difficult. These results suggest that simulators will not necessarily need haptic feedback to train the most important knowledge and skills needed for FESS.

Attitude of Health Personnel↗

PubMed2003

Extended versus limited lymph nodes dissection technique for adenocarcinoma of the stomach.

BACKGROUND: Surgeons disagree about the merits and risks of radical lymph node clearance during gastrectomy for cancer. OBJECTIVES: To evaluate survival and peri-operative mortality after limited or extended lymph node removal during gastrectomy for cancer. SEARCH STRATEGY: We searched MEDLINE, EMBASE, CancerLit, LILACS, Central Medical Journal Japanese Database and the Cochrane register, references from relevant articles and conference proceedings. We contacted known workers in the field. SELECTION CRITERIA: Studies published after 1970 which reported 5 year survival or postoperative mortality rates, and clearly defined the node dissection performed, were considered. We excluded studies which overtly included patients receiving perioperative chemotherapy, and comparisons with clear systematic treatment allocation bias. Randomised controlled trials (RCTs), non-randomised comparisons and observational studies were considered separately. DATA COLLECTION AND ANALYSIS: Three reviewers selected trials for inclusion. Quality assessment and data extraction were performed independently by two reviewers. Results of trials of similar design were pooled. Meta-analysis was performed separately for randomised and non-randomised comparisons. MAIN RESULTS: Two randomised and two non-randomised comparisons of limited (D1) versus extended (D2) node dissection and 11 cohort studies of either D1 or D2 resection were analysed. Meta-analysis of randomised trials did not reveal any survival benefit for extended lymph node dissection (Risk ratio = 0.95 (95% CI 0.83 - 1.09), but showed increased postoperative mortality (RR 2.23, 95% CI 1.45 - 3.45). Pre-specified subgroup analysis suggested a possible benefit in stage T3+ tumours (RR = 0.68, 95% CI 0.42-1.10). Non-randomised comparisons showed no significant survival benefit for extended dissection (RR 0.92, 95% CI 0.83 -1.02), but decreased mortality (RR 0.65, 95% CI 0.45-0.93). Subgroup analysis showed apparent benefit in UICC stage II and IIIa. Observational studies of D2 resection reported much better mortality and survival than those of D1 surgery, but the settings were strikingly different. REVIEWER'S CONCLUSIONS: D2 dissection carries increased mortality risks associated with spleen and pancreas resection, and probably with inexperience and low case volumes. Randomised studies show no evidence of overall survival benefit, but possible benefit in T3+ tumours. These results may be confounded by surgical learning curves and poor surgeon compliance. Non-randomised comparisons suggest a possible survival benefit for D2 in intermediate UICC stages. Observational studies show high 5 year survival and low operative mortality after D2 dissection in experienced units, and poor results after D1 dissection in non-specialist units. Further studies, with precautions to eliminate learning curve effects, contamination and non-compliance, are needed to evaluate D2 dissection in intermediate stage gastric cancer.

Adenocarcinoma↗

PubMed2004

Extended versus limited lymph nodes dissection technique for adenocarcinoma of the stomach.

BACKGROUND: Surgeons disagree about the merits and risks of radical lymph node clearance during gastrectomy for cancer. OBJECTIVES: To evaluate survival and peri-operative mortality after limited or extended lymph node removal during gastrectomy for cancer. SEARCH STRATEGY: We searched MEDLINE, EMBASE, CancerLit, LILACS, Central Medical Journal Japanese Database and the Cochrane register, references from relevant articles and conference proceedings. We contacted known workers in the field. SELECTION CRITERIA: Studies published after 1970 which reported 5 year survival or postoperative mortality rates, and clearly defined the node dissection performed, were considered. We excluded studies which overtly included patients receiving perioperative chemotherapy, and comparisons with clear systematic treatment allocation bias. Randomised controlled trials (RCTs), non-randomised comparisons and observational studies were considered separately. DATA COLLECTION AND ANALYSIS: Three reviewers selected trials for inclusion. Quality assessment and data extraction were performed independently by two reviewers. Results of trials of similar design were pooled. Meta-analysis was performed separately for randomised and non-randomised comparisons. MAIN RESULTS: Two randomised and two non-randomised comparisons of limited (D1) versus extended (D2) node dissection and 11 cohort studies of either D1 or D2 resection were analysed. Meta-analysis of randomised trials did not reveal any survival benefit for extended lymph node dissection (Risk ratio = 0.95 (95% CI 0.83 - 1.09), but showed increased postoperative mortality (RR 2.23, 95% CI 1.45 - 3.45). Pre-specified subgroup analysis suggested a possible benefit in stage T3+ tumours (RR = 0.68, 95% CI 0.42-1.10). Non-randomised comparisons showed no significant survival benefit for extended dissection (RR 0.92, 95% CI 0.83 -1.02), but decreased mortality (RR 0.65, 95% CI 0.45-0.93). Subgroup analysis showed apparent benefit in UICC stage II and IIIa. Observational studies of D2 resection reported much better mortality and survival than those of D1 surgery, but the settings were strikingly different. REVIEWERS' CONCLUSIONS: D2 dissection carries increased mortality risks associated with spleen and pancreas resection, and probably with inexperience and low case volumes. Randomised studies show no evidence of overall survival benefit, but possible benefit in T3+ tumours. These results may be confounded by surgical learning curves and poor surgeon compliance. Non-randomised comparisons suggest a possible survival benefit for D2 in intermediate UICC stages. Observational studies show high 5 year survival and low operative mortality after D2 dissection in experienced units, and poor results after D1 dissection in non-specialist units. Further studies, with precautions to eliminate learning curve effects, contamination and non-compliance, are needed to evaluate D2 dissection in intermediate stage gastric cancer.

Adenocarcinoma↗

PubMed2006

Learning and performance of tracheal intubation by novice personnel: a comparison of the Airtraq and Macintosh laryngoscope.

Direct laryngoscopic tracheal intubation is taught to many healthcare professionals as it is a potentially lifesaving procedure. However, it is a difficult skill to acquire and maintain, and, of concern, the consequences of poorly performed intubation attempts are potentially serious. The Airtraq Laryngoscope is a novel intubation device which may possess advantages over conventional direct laryngoscopes for use by novice personnel. We conducted a prospective trial with 40 medical students who had no prior airway management experience. Following brief didactic instruction, each participant took turns in performing laryngoscopy and intubation using the Macintosh and Airtraq devices under direct supervision. Each student was allowed up to three attempts to intubate in three laryngoscopy scenarios using a Laerdal Intubation Trainer and one scenario in a Laerdal SimMan Manikin. They then performed tracheal intubation of the normal airway a second time to characterise the learning curve for each device. The Airtraq provided superior intubating conditions, resulting in greater success of intubation, particularly in the difficult laryngoscopy scenarios. In both easy and simulated difficult laryngoscopy scenarios, the Airtraq decreased the duration of intubation attempts, reduced the number of optimisation manoeuvres required, and reduced the potential for dental trauma. The Airtraq device showed a rapid learning curve and the students found it significantly easier to use. The Airtraq appears to be a superior device for novice personnel to acquire the skills of tracheal intubation.

Airway Obstruction↗

PubMed2002

Implantation and capsular bag stability of single-piece, foldable EasAcryl 1 intraocular lenses.

PURPOSE: To assess the folding and implantation of the single-piece EasAcryl 1 intraocular lens (IOL) and the maintenance of the tunnel structure and capsular bag stability after implantation. SETTING: S. Orsola Hospital Department of Pathophysiologic Optics, University of Bologna, Bologna, Italy. METHODS: This study comprised 300 cases of EasAcryl 1 IOL implantation. First, a 3.2 mm corneal incision was made according to preoperative astigmatism followed by a 5.5 mm +/- 0.3 (SD) capsulorhexis. After sutureless phacoemulsification using a venturi pump, the 6.0 mm optic, 11.0 mm diameter IOL was implanted using a hexagonal cartridge. The IOLs were implanted using a 2-step maneuver when the superior haptic was grasped with the forceps (first case) or a 1-step maneuver when only the Microsert injector was used. The cartridge was never pushed beyond the tunnel. The preoperative and postoperative incision size and the corneal surgically induced astigmatism were recorded. The IOL rotation was measured 30 +/- 5 days and 8 +/- 1 months postoperatively. RESULTS: No intraoperative complications occurred after the learning curve. No alteration in astigmatism was observed. The mean IOL rotation was 1.04 +/- 0.5 degrees at 30 +/- 5 days and 1.02 +/- 0.2 degrees at 8 +/- 1 months. CONCLUSIONS: The EasAcryl 1 was easily implantation through a 3.2 mm tunnel without altering the natural architecture. The unfolding of the IOL was well controlled, and the IOL remained well centered. A short learning curve is required.

Acrylic Resins↗

PubMed2006

Robotic prostatectomy: a pooled analysis of published literature.

OBJECTIVE: Robotic prostatectomy has been recently added to the treatment armamentarium of localized prostate cancer. We reviewed published data on this modality with critical appraisal of outcomes and complications. METHODS: A Medline search was performed that encompassed all published articles on robotic prostatectomy. Select data on open radical retropubic (RRP) and laparoscopic (LP) prostatectomy from centers of excellence in the USA and Europe were included for objective comparison. Perioperative parameters, pathological results, including surgical margin rate, complications and postoperative continence and potency rates were reported. Advantages and shortcomings of robotic prostatectomy, and the learning curve and cost issues were also addressed. RESULTS: Robotic prostatectomy offers advantages of minimally invasive access surgery, including enhanced visualization, decreased bleeding and transfusion rate, shorter hospital stay and faster recovery. Pathological outcomes are comparable to RRP and LP with acceptable positive margin rate. At short-term follow-up, continence and potency results appear to be equivalent to RRP and LP. The learning curve of robotic prostatectomy is faster than that of LP. Cost remains a matter of debate at the present time. Long-term cancer control results of robotic prostatectomy are still maturing. CONCLUSIONS: Robotic prostatectomy is a promising minimally invasive surgical approach for men with localized prostate cancer. Short-term clinical and pathological results compare favorably to RRP and LP.

Humans↗

PubMed2000

Learning in medicine: chorionic villus sampling.

Operator experience is considered to influence the safety and success of medical procedures. We performed a retrospective survey to assess learning curves in chorionic villus sampling (CVS). Data of 2081 consecutive women, in whom CVS was carried out in a tertiary care university hospital for prenatal diagnosis, were available for analysis. Endpoints of the analysis were fetal loss, failure of the procedure and need for several needle insertions. Frequencies of each endpoint were calculated and plotted for consecutive series of 50 samplings per operator. Logistic regression analysis was used to quantify the effect of operator experience. We observed a statistically significant learning effect for the unit as a whole as assessed by fetal loss figures and the same tendency for need to do several insertions. We did not observe a (collective) learning effect for failure of the procedure. Individual operators showed a significant learning profile for some endpoints. The individual learning profile predominantly depended on previous experience in amniocentesis. Our study substantiates the presence of a learning curve for CVS. This supports the view that centralization and restriction of CVS to a limited number of experienced operators within centres, is likely to have a positive influence on safety and success of the procedure.

Abortion, Spontaneous↗

PubMed1996

Sematech: purpose and performance.

In previous research, we have found a steep learning curve in the production of semiconductors. We estimated that most production knowledge remains internal to the firm, but that a significant fraction "spills over" to other firms. The existence of such spillovers may justify government actions to stimulate research on semiconductor manufacturing technology. The fact that not all production knowledge spills over, meanwhile, creates opportunities for firms to form joint ventures and slide down their learning curves more efficiently. With these considerations in mind, in 1987 14 leading U.S. semiconductor producers, with the assistance of the U.S. government in the form of $100 million in annual subsidies, formed a research and development (R&D) consortium called Sematech. In previous research, we estimated that Sematech has induced its member firms to lower their R&D spending. This may reflect more sharing and less duplication of research, i.e., more research being done with each R&D dollar. If this is the case, then Sematech members may wish to replace any funding withdrawn by the U.S. government. This in turn would imply that the U.S. government's contributions to Sematech do not induce more semiconductor research than would otherwise occur.

Costs and Cost Analysis↗

PubMed2005

Comparison of skill training with robotic systems and traditional endoscopy: implications on training and adoption.

BACKGROUND: Robotic systems are being used by an increasing number of surgeons. This environment is markedly different from that of traditional surgery and involves videoscopic guidance, remote surgical control, and the loss of haptic feedback. Defining how surgeons learn with these systems is necessary to establish training protocols for this technology. This study compared the learning curve for a robotic surgical system with that of traditional endoscopy in the performance of two standardized skill drills. MATERIALS AND METHODS: Twenty participants (average age 27 +/- 4 years, six females) repeated two standardized endoscopic dexterity and depth perception drills for 15 repetitions with the ZEUS robotic surgical system and manual endoscopic instruments (MAN). A score combining time and precision was given for each repetition. The learning curves and overall performance with and without robotic assistance were compared. RESULTS: For both MAN and ZEUS, improvements in performance were significantly greatest during the first five repetitions (P < 0.01, for both). Participants reached the training curve plateau faster with ZEUS than with conventional instruments (8th versus 10th for both drills). Using robotic assistance, dominant and non-dominant hand performance were statistically similar. The number of errors committed with ZEUS were significantly fewer for drill two (0.09 errors/repetition versus 0.24 errors/repetition, P = 0.002) compared to manual technique. CONCLUSIONS: This study demonstrated that training curves for conventional and robotic-assisted systems are remarkably similar. This should prove useful in the training and education of this new technology. This study further suggested that robotics may increase ambidexterity by improving non-dominant hand performance.

Adult↗

PubMed1992

Laparoscopic gastrointestinal and gallbladder surgery: will the promise be fulfilled?

The results of the first 181 consecutive patients who underwent laparoscopic cholecystectomy and 12 patients who underwent laparoscopic colon resection in our hospital are described. Our results show that laparoscopic cholecystectomy has proved to be the standard surgical procedure for treating gallbladder disease. The place of laparoscopic surgery in the treatment of other abdominal diseases is less clear. Our results in laparoscopic colon surgery indicate that a laparoscopic approach in segmental colon resection is feasible. The operation time is long, however, expressing the long learning curve for the operating team, as well as the technical difficulties encountered with this minimal invasive method. On the other hand, it has been proved that large abdominal operations can be performed via the laparoscope. By improving the laparoscopic instruments and increasing the laparoscopic surgeon's experience, further application of this method in gastrointestinal surgery may be expected. Surgeons should, however, be aware of the long learning curve involved in advanced laparoscopic surgery.

Adolescent↗

PubMed2001

Laparoscopic radical prostatectomy. Technical aspects and experience with 125 cases.

PURPOSE: The laparoscopic access for radical prostatectomy offers an alternative to the open surgical procedure with less morbidity. We report on our experience with 125 laparoscopic prostatectomies, especially with respect to making the laparoscopic approach a routine procedure and with a view to the oncological and functional results. MATERIAL AND METHODS: From June 1999 to September 2000, we performed 125 laparoscopic prostatectomies. These included only patients with cancer stages T1 or T2. The mean PSA concentration was 10.5 ng/ml. Forty-four percent of the patients had undergone previous abdominal and 19% previous transurethral surgery. For our laparoscopic prostatectomies we used the descending technique. Free-hand laparoscopic suturing and in situ knot-tying technique were used for the urethrovesical anastomosis. The mobilized specimens were removed in an endobag via a muscle splitting incision. RESULTS: All 125 procedures could be completed successfully. No case required conversion to open surgery. The average operating time was 255 min, the last 40 procedures taking 200 min only. Mean blood loss was 185 ml. Two patients (2%) required postoperative blood transfusion. After an initial learning curve, catheter remained in place for an average of 5.5 days, and the average postoperative stay in hospital was 8 days. Intraoperative complications were seen in 5 patients (4%). In 13 patients (10.4%) postoperative complications were observed. 86% of the patients are continent 6 months postoperatively. Preservation of the neurovascular bundle and sexual potency is possible. CONCLUSION: Laparoscopic radical prostatectomy is an ambitious procedure with a steep learning curve, especially for the laparoscopic dissecting and suturing technique. The excellent sight for dissection results in a reduced blood loss and faster convalescence with an overall lower morbidity. Also with regard to oncological and functional (continence) results the minimally invasive access is at least equivalent to the open procedure. In our opinion, laparoscopic prostatectomy will be the future method of choice for radical prostatectomy.

Adult↗

PubMed2002

Validation and learning in the Procedicus KSA virtual reality surgical simulator.

BACKGROUND: Advanced simulator training within medicine is a rapidly growing field. Virtual reality simulators are being introduced as cost-saving educational tools, which also lead to increased patient safety. METHODS: Fifteen medical students were included in the study. For 10 medical students performance was monitored, before and after 1 h of training, in two endoscopic simulators (the Procedicus KSA with haptic feedback and anatomical graphics and the established MIST simulator without this haptic feedback and graphics). Five medical students performed 50 tests in the Procedicus KSA in order to analyze learning curves. One of these five medical students performed multiple training sessions during 2 weeks and performed more than 300 tests. RESULTS: There was a significant improvement after 1 h of training regarding time, movement economy, and total score. The results in the two simulators were highly correlated. CONCLUSION: Our results show that the use of surgical simulators as a pedagogical tool in medical student training is encouraging. It shows rapid learning curves and our suggestion is to introduce endoscopic simulator training in undergraduate medical education during the course in surgery when motivation is high and before the development of "negative stereotypes" and incorrect practices.

Computer Simulation↗

PubMed1995

Subcoronary implantation or aortic root replacement for human tissue valves: sufficient data to prefer either technique?

The aortic root replacement technique with aortic allograft or pulmonary autograft might be superior to the subcoronary allograft implantation technique with regard to aortic regurgitation. We explored the influence of the learning process on the incidence of reoperation and the severity of postoperative aortic regurgitation as assessed by color Doppler echocardiography. The subcoronary implantation technique was used in 81 patients, and root replacement was done in 63 patients. The first 30 patients of each group were considered as the surgeons' learning curve. Reoperations were more common in the subcoronary implantation group. After exclusion of early reoperations, the median regurgitation score based on echocardiographic examination was 0.22 in the first 30 patients from the subcoronary implantation group and 0.14 in the root replacement group. The subsequent patients from these groups had regurgitation scores of 0.20 and 0.17, respectively. Statistical analysis of these data showed no significant difference. This interim report suggests that the learning curve for the surgical procedure and the grouping of echocardiographic data influence the interpretation of follow-up studies. The superiority of either technique with regard to aortic regurgitation has yet to be proved.

Adolescent↗

PubMed2003

Hand-assisted laparoscopic nephrectomy for stage T1 and large stage T2 renal tumors.

BACKGROUND AND PURPOSE: Standard laparoscopic nephrectomy (LN) has been shown to be as effective oncologically as open surgery for both stage T1 and stage T2 renal tumors. While much has been published regarding the increasing indications for laparoscopic nephrectomy, there is little in the literature regarding the advantages of hand-assisted laparoscopy (HAL) for the treatment of large (>7-cm) stage T2 renal tumors. To our knowledge, this study is the first to directly compare the results in pathologic stage T1 and stage T2 tumors. Our aim was to assess whether HAL nephrectomy for these larger tumors maintains the same advantages enjoyed by HAL for the smaller ones (<7 cm). PATIENTS AND METHODS: One hundred HAL renal extirpative procedures were performed over a 3-year period. Of these, 60 were radical nephrectomies for malignant disease, of which 50 tumors were stage T1 and 10 stage T2. Standard HAL nephrectomy was performed through a vertical midline or paramedian incision, and the specimen was sent for histologic examination and tumor staging. We retrospectively analyzed our charts to determine if HAL nephrectomy for T2 tumors was as advantageous as for T1 tumors. We collected data on patient age, ASA score, average tumor size, estimated blood loss, operative time, conversion rate, rate of complications, and length of hospital stay. Follow-up ranged from 4 to 26 months with a mean of 11 months. RESULTS: The mean size was 4.68 and 9.22 cm for stage T1 and T2 tumors, respectively. Intraoperatively, stage T2 tumors were associated with less blood loss than were T1 tumors (105 mL v 190 mL). Operative times were equivalent, at 190 and 185 minutes for stage T1 and T2, respectively. No open conversions were required in the T2 group v four (8.7%) in the T1 group. Three of these open conversions were seen in the first 25 HAL cases. No complications or conversions were seen in the stage T2 patients. Of note, the majority of the operations for stage T2 disease were performed after the learning curve had been surpassed. CONCLUSION: The HAL nephrectomy maintains the benefits associated with standard LN. Stage T1 and T2 tumors are equally amenable to HAL nephrectomy, enjoying the same perioperative advantages. The larger size of the higher-stage tumors does not appear to hinder intact organ removal via a 7-cm hand incision. For the novice laparoscopist, we recommend approaching smaller tumors first with HAL nephrectomy, as there is a learning curve. As surgical expertise with HAL nephrectomy increases, larger tumors (stage T2) can be removed safely and expeditiously with little blood loss and a low complication rate. In the short term, patients with stage T2 cancers appear to enjoy the same disease-free survival rate as those with tumors of lower stage. Longer-term follow-up is clearly needed; however, we anticipate the same excellent results as have been demonstrated by others performing conventional radical LN.

Blood Loss, Surgical↗