La validation des techniques en chirurgie laparoscopique [Validation of laparoscopic surgical techniques].

The use of laparoscopic surgery has increased rapidly. However, a technically feasible procedure is not automatically recommendable. Thus, if cholecystectomy and fundoplication are currently fully validated techniques, this does not hold true for gastroplasty and kidney harvesting for transplantation: these operations are feasible indeed but their efficacy remains to be proved. Laparoscopic oncology has been shown to be feasible too, but its efficacy has not been documented yet.

Human papilloma virus type and recurrence rate after surgical clearance of anal condylomata acuminata.

BACKGROUND: Anal condylomata acuminata (ACA) are caused by human papilloma virus (HPV) infection which is transmitted by close physical and sexual contact. The result of surgical treatment of ACA has an overall success rate of 71% to 93%, with a recurrence rate between 4% and 29%. The aim of this study was to assess a possible association between HPV type and ACA recurrence after surgical treatment. METHODS: We performed a retrospective analysis of 140 consecutive patients who underwent surgery for ACA from January 1990 to December 2005 at our tertiary University Hospital. We confirmed ACA by histopathological analysis and determined the HPV typing using the polymerase chain reaction. Patients gave consent for HPV testing and completed a questionnaire. We looked at the association of ACA, HPV typing, and HIV disease. We used chi, the Monte Carlo simulation, and Wilcoxon tests for statistical analysis. RESULTS: Among the 140 patients (123 M/17 F), HPV 6 and 11 were the most frequently encountered viruses (51% and 28%, respectively). Recurrence occurred in 35 (25%) patients. HPV 11 was present in 19 (41%) of these recurrences, which is statistically significant, when compared with other HPVs. There was no significant difference between recurrence rates in the 33 (24%) HIV-positive and the HIV-negative patients. CONCLUSIONS: HPV 11 is associated with higher recurrence rate of ACA. This makes routine clinical HPV typing questionable. Follow-up is required to identify recurrence and to treat it early, especially if HPV 11 has been identified.

Surgical outcomes of Baerveldt aqueous shunt implantation versus combined phacoemulsification and Baerveldt aqueous shunt implantation

Purpose: To examine the efficacy and safety of Baerveldt shunt (BS) implantation compared to combined phacoemulsification and Baerveldt shunt implantation (PBS). This study was designed to detect a difference in IOP reduction of 20% (~4mmHg) between groups with 90% power. Methods: Sixty patients with medically uncontrolled glaucoma, prospectively underwent either or BS implantation with phacoemulsification (Group PBS; n=30) or BS implantation alone (group BS; n=30, pseudophakic eyes only). Groups were matched for age, glaucoma subtype and length of follow-up. Pre and post-operative measures recorded included patient demographics, visual acuity, IOP, number of glaucoma medications (GMs) and all complications. Success was defined as IOP≤21mmHg and 20% reduction in IOP from baseline with or without GMs. Results: Age of PBS and BS groups was 61 vs 62 years respectively (p=0.72*). There were no significant differences in preoperative baseline characteristics: PBS vs PB, mean IOP =25.5mmHg (standard deviation (SD); ±10.3mmHg) vs 26.1mmHg (SD ±10.6mmHg), p=0.81*; mean GMs=3.0 (SD ±1.1) vs 3.1 (SD ±1.0), p=0.83*; mean VA=0.3 vs 0.3, p=0.89*. At year one there were no significant differences observed between groups in post-operative IOP, GMs or VA, mean IOP =14.1mmHg (SD ±5.4mmHg) vs 11.5 mmHg (SD ±4.2mmHg), p=0.12*; mean GMs=1.6 (SD ±1.4) vs 1.1 (SD ±1.1), p=0.23*; mean VA=0.5 vs 0.4, p=0.46*. Complication rates were similar between the two groups (7% vs 14%). Success rate was lower in eyes with PBS (71%) than with BS (88%), however this did not reach statistical significance (p=0.95, log-rank test). * two-sample t-test Conclusions: There were no significant differences at year one in success or complication rates between PBS and BS groups suggesting that simultaneous phacoemulsification does not have a marked (difference of >4mmHg) effect on tube function. IOP reduction and success were less in the PBS group, a larger sample (n=120) would be required to investigate if there is a 10% difference in IOP reduction between groups, however it is unclear if this would be a clinically significant difference to justify separate surgeries.

Segmentation of Head and Neck Lymph Node Regions for Radiotherapy Planning Using Active Contour-Based Atlas Registration

In this paper, we present the segmentation of the headand neck lymph node regions using a new active contourbased atlas registration model. We propose to segment thelymph node regions without directly including them in theatlas registration process; instead, they are segmentedusing the dense deformation field computed from theregistration of the atlas structures with distinctboundaries. This approach results in robust and accuratesegmentation of the lymph node regions even in thepresence of significant anatomical variations between theatlas-image and the patient's image to be segmented. Wealso present a quantitative evaluation of lymph noderegions segmentation using various statistical as well asgeometrical metrics: sensitivity, specificity, dicesimilarity coefficient and Hausdorff distance. Acomparison of the proposed method with two other state ofthe art methods is presented. The robustness of theproposed method to the atlas selection, in segmenting thelymph node regions, is also evaluated.

Model-based Segmentation and Image Fusion of 3D Computed Tomography and 3D Ultrasound of the Eye for Radiotherapy Planning

For radiotherapy treatment planning of retinoblastoma inchildhood, Computed Tomography (CT) represents thestandard method for tumor volume delineation, despitesome inherent limitations. CT scan is very useful inproviding information on physical density for dosecalculation and morphological volumetric information butpresents a low sensitivity in assessing the tumorviability. On the other hand, 3D ultrasound (US) allows ahigh accurate definition of the tumor volume thanks toits high spatial resolution but it is not currentlyintegrated in the treatment planning but used only fordiagnosis and follow-up. Our ultimate goal is anautomatic segmentation of gross tumor volume (GTV) in the3D US, the segmentation of the organs at risk (OAR) inthe CT and the registration of both. In this paper, wepresent some preliminary results in this direction. Wepresent 3D active contour-based segmentation of the eyeball and the lens in CT images; the presented approachincorporates the prior knowledge of the anatomy by usinga 3D geometrical eye model. The automated segmentationresults are validated by comparing with manualsegmentations. Then, for the fusion of 3D CT and USimages, we present two approaches: (i) landmark-basedtransformation, and (ii) object-based transformation thatmakes use of eye ball contour information on CT and USimages.

Caspofungin for prevention of intra-abdominal candidiasis in high-risk surgical patients.

PURPOSE: Thirty to forty percent of patients with recurrent gastrointestinal perforation/anastomotic leakage or acute necrotizing pancreatitis develop intra-abdominal invasive candidiasis (IC). A corrected Candida colonization index (CCI) > or =0.4 is a powerful predictor of IC. Fluconazole prevents intra-abdominal IC in this setting, but azole-resistant Candida species are emerging. The aim of this study was to explore the efficacy and safety of caspofungin for prevention of intra-abdominal IC in high-risk surgical patients. METHODS: Prospective non-comparative single-center study in consecutive adult surgical patients with recurrent gastrointestinal perforation/anastomotic leakage or acute necrotizing pancreatitis. Preventive caspofungin therapy (70 mg, then 50 mg/day) was given until resolution of the surgical condition. Candida colonization index and CCI, occurrence of intra-abdominal IC and adverse events were monitored. RESULTS: Nineteen patients were studied: 16 (84%) had recurrent gastrointestinal perforation/anastomotic leakage and 3 (16%) acute necrotizing pancreatitis. The median duration of preventive caspofungin therapy was 16 days (range 4-46). The colonization index decreased significantly during study therapy, and the CCI remained <0.4 in all patients. Caspofungin was successful for prevention of intra-abdominal IC in 18/19 patients (95%, 1 breakthrough IC 5 days after inclusion). No drug-related adverse event requiring caspofungin discontinuation occurred. CONCLUSION: Caspofungin may be efficacious and safe for prevention of intra-abdominal candidiasis in high-risk surgical patients. This needs to be further investigated in randomized trials.

Expérience de dix ans de réanimation chirurgicale d'un centre hospitalier universitaire. Détermination d'un critère d'identification des patients à risque de décéder de coagulopathie irréversible [10 years experience in surgical resuscitation at a university hospital center. Determination of a criterion for identifying patients at risk for fatal irreversible coagulopathy]

The authors evaluated ten years of surgical reanimation in the University Centre of Lausanne (CHUV). Irreversible coagulopathy (IC) is the predominant cause of death for the polytraumatized patient. Acidosis, hypothermy, and coagulation troubles are crucial elements of this coagulopathy. The authors looked for a criterion allowing the identification of dying of IC. In a retrospective study, laboratory results of pH, TP, PTT, thrombocyte count and the need for blood transfusion units were checked for each major step of the primary evaluation and treatment of the polytraumatized patients. These results were considered as critical according to criteria of the literature (30). The authors conclude that the apparation of a third critical value may be useful to identify the polytraumatized patient at risk of dying of IC status. This criterion may also guide the trauma team in selecting a damage control surgical approach (DCS). This criterion was then introduced into an algorithm involving the Emergency Department, the operating room and the Intensive Care Unit. This criterion is a new tool to address the patient at the crucial moment to the appropriate hospital structure.

Value of positron emission tomography in full-thickness chest wall resections for malignancies.

Preoperative imaging for resection of chest wall malignancies is generally performed by computed tomography (CT). We evaluated the role of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in planning full-thickness chest wall resections for malignancies. We retrospectively included 18 consecutive patients operated from 2004 to 2006 at our institution. Tumor extent was measured by CT and PET, using the two largest perpendicular tumor extensions in the chest wall plane to compute the tumor surface assuming an elliptical shape. Imaging measurements were compared to histopathology assessment of tumor borders. CT assessment consistently overestimated the tumor size as compared to PET (+64% vs. +1%, P<0.001). Moreover, PET was significantly better than CT at defining the size of lesions >24 cm(2) corresponding to a mean diameter >5.5 cm or an ellipse of >4 cm x 7.6 cm (positive predictive value 80% vs. 44% and specificity 93% vs. 64%, respectively). Metabolic PET imaging was superior to CT for defining the extent of chest wall tumors, particularly for tumors with a diameter >5.5 cm. PET can complement CT in planning full-thickness chest wall resection for malignancies, but its true value remains to be determined in larger, prospective studies.

The future of patient safety: Surgical trainees accept virtual reality as a new training tool.

BACKGROUND: The use of virtual reality (VR) has gained increasing interest to acquire laparoscopic skills outside the operating theatre and thus increasing patients' safety. The aim of this study was to evaluate trainees' acceptance of VR for assessment and training during a skills course and at their institution. METHODS: All 735 surgical trainees of the International Gastrointestinal Surgery Workshop 2006-2008, held in Davos, Switzerland, were given a minimum of 45 minutes for VR training during the course. Participants' opinion on VR was analyzed with a standardized questionnaire. RESULTS: Fivehundred-twenty-seven participants (72%) from 28 countries attended the VR sessions and answered the questionnaires. The possibility of using VR at the course was estimated as excellent or good in 68%, useful in 21%, reasonable in 9% and unsuitable or useless in 2%. If such VR simulators were available at their institution, most course participants would train at least one hour per week (46%), two or more hours (42%) and only 12% wouldn't use VR. Similarly, 63% of the participants would accept to operate on patients only after VR training and 55% to have VR as part of their assessment. CONCLUSION: Residents accept and appreciate VR simulation for surgical assessment and training. The majority of the trainees are motivated to regularly spend time for VR training if accessible.

Surgical treatment of lamellar macular hole associated with epimacular membrane.

BACKGROUND:: Although the surgical treatment of full-thickness macular hole is well established, the utility of pars plana vitrectomy in the treatment of lamellar macular hole (LMH) remains less clear. The purpose of the study is to report functional results of surgical treatment of LMH associated with epiretinal membrane. METHODS:: Retrospective chart review of patients undergoing pars plana vitrectomy and peeling of epiretinal membrane and internal limiting membrane, with or without air or gas tamponade, for symptomatic LMH associated with epimacular membrane. RESULTS:: Forty-five eyes of 44 patients were operated for LMH associated with epimacular membrane between May 2000 and July 2009. Pars plana vitrectomy and membrane peeling were combined with air or gas tamponade in 43 of 45 cases. Mean logarithm of the minimum angle of resolution best-corrected visual acuity improved from 0.4 preoperatively to 0.13 postoperatively (P < 0.0001). Improvement in visual acuity ranged from 0 Early Treatment Diabetic Retinopathy Study (ETDRS) lines to 8.9 ETDRS lines (mean, 2.65 ETDRS lines). Visual acuity improved by ≥1 ETDRS line(s) in 40 of 45 eyes (89%) and by ≥2 ETDRS lines in 26 of 45 eyes (58%) after the surgical procedure. No patient lost vision. CONCLUSION:: This small retrospective study suggests that surgical treatment of LMH associated with epimacular membrane may improve visual acuity in symptomatic patients.