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En el presente trabajo se muestra una experiencia relacionada con la utilización de los Entornos Virtuales de Enseñanza Aprendizaje (EVEA) como recurso didáctico durante el desarrollo de en una práctica de laboratorio de Física II para las carreras de ingeniería en la universidad de Holguín. El objetivo del trabajo radica en presentar los resultados de la implementación de una práctica de laboratorio a través de la plataforma Moodle. Se muestra además, de manera detallada, cómo fue estructurado un laboratorio tradicional en cuanto a diseño, toma de datos, procesamiento estadístico y presentación de los resultados, para poder desarrollarlo como un laboratorio remoto (diferido), contribuyendo así a la utilización de las Tecnologías de la Información y las Comunicaciones (TIC) en el proceso de enseñanza-aprendizaje de la Física. Por último se dan a conocer los resultados obtenidos en una encuesta aplicada a los estudiantes para conocer el nivel de satisfacción de los mismos durante el desarrollo de la práctica de laboratorio.

Background: Infections after shoulder surgery are potentially devastating complications. Propionibacterium acnes is recognized as a causal agent in shoulder infections. The clinical presentation is usually insidious and nonspecific, but a P. acnes infection could be an occult cause of postoperative shoulder pain.Questions/purposes: What are the clinical and microbiologic characteristics of a postsurgical P. acnes shoulder infection and how should it be addressed?Patients and Methods: Ten patients with an average age of 57 years presented with P. acnes postsurgical shoulder infection. Clinical infection signs and surgical history were assessed and joint aspirates and tissue biopsy specimens were obtained. Diagnosis was confirmed by microbiologic cultures.Results: At the time of confirmation of the diagnosis, clinical signs of infection were absent. C-reactive protein and erythrocyte sedimentation rates were inconsistently elevated. Cultures took a mean 7 days to confirm organism growth. The average time from surgery to diagnosis of infection was 1.8 years (range, 0.07-8.0 years). All patients underwent irrigation and débridement and were treated with antibiotics for 6 weeks.Conclusions: P. acnes shoulder infections should be considered as a cause for persistent, unexplained shoulder pain. Shoulder aspirations and tissue samples should be obtained. Surgical débridement and intravenous antibiotics are necessary treatment modalities.Level Of Evidence: Level IV, Prognostic study. See the Guidelines for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Distal biceps tendon ruptures present with an initial tearing sensation accompanied by acute pain; weakness may follow. The hook test is very reliable for diagnosing ruptures, and magnetic resonance imaging can provide information about the integrity and any intrasubstance degeneration of the tendon. There are subtle differences between the outcomes of single and modified two-incision operative repairs. With regard to complications, there is a higher prevalence of nerve injuries in association with single-incision techniques and a higher prevalence of heterotopic ossification in association with two-incision techniques. Fixation techniques include the use of bone tunnels, suture anchors, interference screws, and cortical fixation buttons. There is no clinical evidence supporting the use of one fixation method over another, although cortical button fixation has been shown to provide the highest load tolerance and stiffness. Postoperative rehabilitation has become more aggressive as fixation methods have improved. [ABSTRACT FROM AUTHOR]

El trabajo aborda problemáticas actuales en la enseñanza de la Física Moderna en Cuba que implican la necesidad de aplicar nuevos objetos virtuales de aprendizaje (OVA) integrales para favorecer el carácter profesionalizador de los estudiantes de Ingeniería Mecánica desde esta ciencia básica. El objetivo fundamental es valorar las ventajas que tienen estos medios con respecto a los utilizados tradicionalmente. La investigación permitió esclarecer la situación actual por la cual atraviesa este proceso en la Universidad de Holguín, así como los resultados de otras investigaciones que fueron asumidos para la utilización de los objetos virtuales de aprendizaje. La metodología que se siguió fue con enfoque mixto. Para ello se realizaron análisis y síntesis de documentos, encuestas y entrevistas a profesores y estudiantes dentro de la aplicación de un experimento pedagógico. De los resultados se revelan datos acerca del uso de estos recursos por los estudiantes y se especifican las características didácticas que deben tener. Finalmente se evalúan los resultados obtenidos en dos grupos dentro de un semestre de clases del curso 2012-2013, uno experimental con la utilización de objetos virtuales de aprendizaje y otro de enseñanza tradicional sin estos recursos. Seguidamente se publican algunos criterios de los estudiantes acerca de la aplicación de esta propuesta en el curso y se analizan las principales transformaciones observadas. Se concluye evaluando la complejidad de la enseñanza de la asignatura y valorando la posibilidad de favorecer el aprendizaje de la misma.

Purpose: The aim of this biomechanical in vitro study was to compare the novel technique of double intramedullary cortical button (DICB) fixation with the well-established method of suture anchor (SA) fixation for distal biceps tendon repair., Methods: A matched-pair analysis (24 human cadaveric radii) was performed with respect to cyclic loadings and failure strengths. Twelve specimens per group were cyclically loaded for 1,000 cycles at 1.5 Hz from 5 to 50 N and from 5 to 100 N, respectively. The tendon-bone displacement was optically analysed using the Image J Software (National Institute of Health). Afterwards, all specimens were pulled to failure. Maximum load to failure and mode of failure were recorded., Results: All DICB constructs passed the cyclic loading test, whereas 4 of the 12 specimens within the SA group failed by anchor pull-out. Cyclic loading showed a mean tendon-bone displacement of 0.6 ± 1.4 mm for the DICB group and 1.4 ± 1.4 mm for the SA group (n.s.) after 1,000 cycles with 50 N, and a mean displacement of 2.1 ± 2.4 mm for the DICB group and 3.5 ± 3.7 mm for the SA group (n.s.) after 1,000 cycles with 100 N. Load to failure testing showed a mean failure load of 312 ± 76 N and a stiffness of 67.1 ± 11.7 N/mm for the DICB technique. The mean load to failure for the SA repair was 200 ± 120 N (n.s.) and the stiffness was 55.9 ± 21.3 N/mm (n.s.)., Conclusions: The novel technique of DICB fixation showed small tendon-bone displacement during cyclic testing and reliable fixation strength to the bone in load to failure. Moreover, all DICB constructs passed cyclic loadings without failure. Based on the current findings, a more aggressive postoperative rehabilitation may be allowed for the DICB repair in clinical use.

Purpose: The purpose of this study was to biomechanically evaluate a new technique of intramedullary cortical button fixation for subpectoral biceps tenodesis and to compare it with the interference screw technique., Methods: We compared intramedullary unicortical button fixation (BicepsButton; Arthrex, Naples, FL) with interference screw fixation (Bio-Tenodesis screw; Arthrex) for subpectoral biceps tenodesis using 10 pairs of human cadaveric shoulders and ovine superficial digital flexor tendons. After computed tomography analysis, the specimens were mounted in a testing machine. Cyclic loading was performed (preload, 5 N; 5 to 70 N at 1.5 Hz for 500 cycles), recording the displacement of the tendon. Load to failure and stiffness were subsequently evaluated with a load-to-failure test (1 mm/s)., Results: Cyclic loading showed a displacement of 11.3 ± 2.8 mm for intramedullary cortical button fixation and 9 ± 1.7 mm for interference screw fixation (P = .112). All specimens within the cortical button group passed the cyclic loading test, whereas 3 of 10 specimens within the interference screw group failed by tendon slippage at the screw-tendon-bone interface after a mean of 252 cycles (P = .221). Load-to-failure testing showed a mean load to failure of 218.8 ± 40 N and stiffness of 27.2 ± 7.2 N/mm for the intramedullary cortical button technique. For the interference screw, the mean load to failure was 212.1 ± 28.3 N (P = .625) and stiffness was 40.4 ± 13 N/mm (P = .056)., Conclusions: We could not find any major differences in load to failure when comparing the tested techniques for subpectoral biceps tenodesis. Intramedullary cortical button fixation showed no failure during cyclic testing. However, we found a 30% failure rate (3 of 10) for the interference screw fixation., Clinical Relevance: Intramedullary cortical button fixation provides an alternative technique for subpectoral biceps tenodesis with comparable and, during cyclic loading, even superior biomechanical properties to interference screw fixation., (Copyright © 2013 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: Optimal surgical treatment of high-grade acromioclavicular joint dislocations is still controversially discussed. The purpose of the present controlled laboratory study was to evaluate whether a polydioxansulfate (PDS(®)) cord augmentation with separate reconstruction of the coracoclavicular (CC) ligaments and the acromioclavicular (AC) complex provides sufficient vertical stability in a biomechanical cadaver model., Methods: Twenty-four shoulders of fresh-frozen cadaveric specimen were tested. Cyclic loading and load to failure protocol was performed in vertical direction on 12 native AC joints and repeated after reconstruction. The reconstruction of the coracoclavicular ligament was performed using two CC PDS cerclages and an additional AC PDS cerclage., Results: In static load testing for vertical force, the native AC joint complex measured 590.1 N (±95.8 N), elongation 13.4 mm (±2.1 mm) and stiffness 48.7 N/mm (±12.0 N/mm). The mean maximum load to failure in the reconstructed joints was 569.9 N (±97.9 N), elongation 18.8 mm (±4.7 mm) and stiffness 37.9 N/mm (±8.0 N/mm). During dynamic testing of the reconstructed AC joints, all specimens reached the critical elongation of 12.0 mm, defined as clinical failure between 200 and 300 N. The mean amount of repetitions at clinical failure was 305. A plastic deformation of the reconstructed specimens throughout cyclic loading could not be detected., Conclusion: The AC joint reconstruction with acromioclavicular and coracoclavicular PDS cord cerclages did not provide the aspired vertical stability in a cadaver model., Level of Evidence: Basic Science Study.

The optimal treatment for proximal humeral fractures is controversial. Few data exist concerning the influence of the surgical approach on the outcome. The purpose of this study was to evaluate the clinical and radiological outcomes of proximal humeral fractures treated with locking plate fixation through a deltopectoral vs an anterolateral deltoid-splitting approach. Of 86 patients who met the inclusion criteria, 70 were available for follow-up examination. Thirty-three patients were treated through a deltopectoral approach and 37 through an anterolateral deltoid-splitting approach. In all cases, open reduction and internal fixation with a PHILOS locking plate (Synthes, Umkirch, Germany) was performed. Clinical follow-up included evaluation of pain, shoulder mobility, and strength. Constant score and Disabilities of the Arm, Shoulder and Hand (DASH) score were assessed. A clinical neurological examination of the axillary nerve was also performed. Consolidation, reduction, and appearance of head necrosis were evaluated radiographically. After a mean follow-up of 33 months, Constant scores, DASH scores, and American Shoulder and Elbow Surgeons scores showed no significant differences between the groups. Clinical neurologic examination of the axillary nerve revealed no obvious damage to the nerve in either group. Deltopectoral and anterolateral detoid-splitting approaches for plate fixation of proximal humeral fractures are safe and provide similar clinical outcomes. The results of this study suggest that the approach can be chosen according to surgeon preference., (Copyright 2012, SLACK Incorporated.)

Background: The in vivo stabilizing role of the long head of the biceps tendon (LHB) is poorly understood. While cadaveric studies report that the loaded LHB constrains translations in all directions, clinical data suggest that there is no clinically demonstrable alteration in glenohumeral position after LHB tenodesis or tenotomy. The purpose of this study was to investigate potential alterations in glenohumeral kinematics after LHB tenodesis during 3 dynamic in vivo motions using a biplane fluoroscopy system., Hypothesis: Our hypothesis was that there would be no difference in glenohumeral translations greater than 1.0 mm between shoulders after biceps tenodesis and healthy contralateral shoulders., Study Design: Controlled laboratory study., Methods: Five patients who underwent unilateral, open subpectoral tenodesis performed abduction, a simulated late cocking phase of a throw, and simulated lifting with both their tenodesed shoulder and their contralateral healthy shoulder inside a biplane fluoroscopy system. Dynamic 3-dimensional glenohumeral positions and electromyography activity of the biceps brachii muscle were determined and compared., Results: Significant glenohumeral translations occurred in both shoulders for abduction (3.4 mm inferiorly; P < .01) and simulated late cocking (2.6 mm anteriorly; P < .01). The mean difference for each motion in glenohumeral position between the tenodesed and the contralateral healthy shoulders was always less than 1.0 mm. The tenodesed shoulders were more anterior (centered) during abduction (0.7 mm; P < .01) and for the eccentric phase of the simulated late cocking motion (0.9 mm; P < .02). No significant differences were found during the simulated lifting motion and in the superior-inferior direction., Conclusion: The effect of biceps tenodesis on glenohumeral position during the motions studied in vivo was minimal compared with physiological translations and interpatient variability., Clinical Relevance: Our findings demonstrated that LHB tenodesis does not dramatically alter glenohumeral position during dynamic motions, suggesting the risk for clinically significant alterations in glenohumeral kinematics after tenodesis is low in otherwise intact shoulders.

Purpose: This study was designed to present the novel technique of intramedullary cortical button fixation for distal biceps tendon repair via a single-limited anterior portal., Methods: To reattach the ruptured biceps tendon at the radial tuberosity, two Bicepsbutton(™) (Arthrex, Naples, FL, USA) were intramedullary positioned to the anterior cortex. The surgical procedure is described in detail. This technique has been performed in a first series of 3 patients with acute distal biceps tendon ruptures., Results: All patients were very satisfied after surgery and would undergo the same surgical procedure again. All patients regained full range of elbow motion with comparable strength of forearm supination and elbow flexion measured against the uninjured arm at 6 months of follow-up. No neurovascular complications have been occured., Conclusion: Double intramedullary cortical button repair has shown to be a safe and reliable fixation method for distal biceps tendon rupture in a small series of patients. Preliminary results are encouraging.

Background: Extramedullary cortical button-based fixation for distal biceps tendon ruptures exhibits maximum load to failure in vitro but cannot restore the anatomic footprint and has the potential risk for injury to the posterior interosseous nerve., Hypothesis: Double intramedullary cortical button fixation repair provides superior fixation strength to the bone when compared with single extramedullary cortical button-based repair., Study Design: Controlled laboratory study., Methods: The technique of intramedullary cortical button fixation with 1 or 2 buttons was compared with single extramedullary cortical button-based repair using 12 paired human cadaveric elbows. All specimens underwent computed tomography analysis to determine intramedullary dimensions of the radial tuberosity as well as the thickness of the anterior and posterior cortices before biomechanical testing. Maximum load to failure and failure modes were recorded. For baseline measurements, the native tendon was tested for maximum load to failure., Results: The intramedullary area of the radial tuberosity provides sufficient space for single or double intramedullary cortical button implantation. The mean thickness of the anterior cortex was 1.13 ± 0.15 mm, and for the posterior cortex it was 1.97 ± 0.48 mm (P < .001). We found the highest loads to failure for double intramedullary cortical button fixation with a mean load to failure of 455 ± 103 N, versus 275 ± 44 N for single intramedullary cortical button fixation (P < .001) and 305 ± 27 N for single extramedullary cortical button-based technique (P = .003). There were no statistically significant differences between single intramedullary and single extramedullary button fixation repair (P = .081). The mean load to failure for the native tendon was 379 ± 87 N., Conclusion: Double intramedullary cortical button fixation provides the highest load to failure in the specimens tested., Clinical Relevance: Double intramedullary cortical button fixation provides reliable fixation strength to the bone for distal biceps tendon repair and potentially minimizes the risk of posterior interosseous nerve injury. Further, based on a 2-point-fixation, this method may offer a wider, more anatomic restoration of the distal biceps tendon to its anatomic footprint.

Background: Lesions of the biceps pulley and instability of the long head of the biceps tendon are common diagnoses in patients with anterior shoulder pain., Purpose: To analyze the pathoanatomy of the biceps reflection pulley ("pulley") in consecutive patients undergoing shoulder arthroscopy., Study Design: Cohort study (prevalence); Level of evidence, 2., Methods: Prospective data were collected on 229 shoulders in consecutive patients (155 male,74 female) who underwent shoulder arthroscopy (121 rotator cuff pathology, 50 instability, 43 osteoarthritis, 15 miscellaneous). The average age was 48.5 years (range, 18-76 years). Sixty-eight shoulders had underwent a previous surgery., Results: The long head of the biceps tendon was absent in 21 shoulders (9.2%); 1 was excluded for incomplete data. In 207 shoulders, the mean width of the long head of the biceps tendon was 6.0 mm (range, 3-10 mm), and the pulley complex, 7.2 mm (range, 4-15 mm). Sixty-seven patients (32.4%) had a pulley tear: 48 shoulders had anteromedial pulley tears, 32 posterolateral, with 13 combined anteromedial-posterolateral lesions. Patients with pulley tears were significantly older than those without (57 vs 44 years, P < .001). For anteromedial pulley tears, the mean width of the long head of the biceps tendon was significantly larger in the torn group (6.4 vs 5.8 mm, P = .012). The anteromedial or posterolateral pulley tears were significantly associated with subluxation or dislocation of the long head of the biceps tendon (P = .001), with a pulley torn in all 27 cases of biceps dislocation. In 173 shoulders with a centered long head of the biceps tendon, the pulley was torn in 36 (23 anteromedial, 18 posterolateral [with 5 being combined]). Pulley tears and rotator cuff injury showed a significant association (P < .001). Superior labral anterior posterior lesions were significantly associated with anteromedial (P < .008) and posterolateral pulley tears (P < .021)., Conclusion: Pulley lesions are fairly common in patients undergoing arthroscopic surgery and were found in 32.4% of this prospective cohort (67 of 207). Current consensus indicates that pulley lesions are often associated with rotator cuff tears. This series also showed correlations with superior labral anterior posterior tears, biceps instability, and long head of the biceps tendon tears.

Lesions of the long head biceps tendon (LHB) are frequent causes of shoulder pain and disability. Biceps tenotomy and tenodesis have gained widespread acceptance as effective procedures to manage both isolated LHB pathology and combined lesions of the rotator cuff and biceps-labral complex. The function of the LHB tendon and its role in glenohumeral kinematics presently remain only partially understood because of the difficulty of cadaveric and in vivo biomechanical studies. The purpose of this article is to offer an up-to-date review of the anatomy and biomechanical properties of the LHB and to provide an evidence-based approach to current treatment strategies for LHB disorders., (Copyright © 2011 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Ruptures of the distal biceps tendon are rare injuries which nearly exclusively occur in middle-aged men when eccentric load is applied to the flexed elbow. Operative treatment is supposed to be the most effective method to restore flexion and supination strength. However, there is a wide variety of potential surgical treatment methods. This article is aiming to present the anatomical, pathophysiological and epidemiological basics and to demonstrate the surgical techniques. Not only the approaches but also the differing fixation methods like bone tunnel fixation, endobutton- or suture anchor and interference screw are described in detail. Additionally, rehabilitation protocols and considerations concerning medical expertise are presented.

This is a review of joint-preservation techniques for the shoulder. Whereas the management of diffuse articular cartilage loss in the glenohumeral joints of elderly and less active patients by total shoulder arthroplasty is well accepted, significant controversy persists in selecting and refining successful operative techniques to repair symptomatic glenohumeral cartilage lesions in the shoulders of young, active patients. The principal causes of focal and diffuse articular cartilage damage in the glenohumeral joint, including previous surgery, trauma, acute or recurrent dislocation, osteonecrosis, infection, chondrolysis, osteochondritis dissecans, inflammatory arthritides, rotator cuff arthropathy, and osteoarthritis, are discussed. Focal cartilage lesions of the glenohumeral joint are often difficult to diagnose and require a refined and focused physical examination as well as carefully selected imaging studies. This review offers a concise guide to surgical decision making and up-to-date summaries of the current techniques available to treat both focal chondral defects and more massive structural osteochondral defects. These techniques include microfracture, osteoarticular transplantation (OATS [Osteochondral Autograft Transfer System]; Arthrex, Naples, FL), autologous chondrocyte implantation, bulk allograft reconstruction, and biologic resurfacing. As new approaches to glenohumeral cartilage repair and shoulder joint preservation evolve, there continues to be a heightened need for collaborative research and well-designed outcomes analysis to facilitate successful patient care.

Background: Anterior cruciate ligament reconstruction with a double-bundle technique requires exact tunnel positioning. Reference values for the anatomic insertions are necessary for radiographic intra- and postoperative control and fluoroscopy-based navigation., Hypothesis: The femoral and tibial insertions of the anteromedial bundle (AMB) and posterolateral bundle (PLB) of the anterior cruciate ligament can be described using standardized computed tomography scans., Study Design: Descriptive laboratory study., Methods: The insertion sites of the AMB and PLB were macroscopically identified and tagged by copper wire in 12 specimens. Computed tomography scans with predefined reconstructions were performed. Femorally, the geometric center of the insertions were determined in the sagittal view and described in a deep-high 10 x 10 grid. Tibially, the insertions were described as the ratio between the geometric center of the insertion sites with respect to the mediolateral and sagittal diameter of the tibia in frontal and sagittal reconstruction, respectively. The tibial insertions were described using a 10 x 10 grid in axial orientation., Results: The geometric midpoints of the insertion areas at the femur of the AMB and PLB were located on the reticule at x = 21% + or - 3% and y = 22% + or - 2% for the AMB and x = 27% + or - 3% and y = 45% + or - 3% for the PLB. In the sagittal plane, the center of the tibial insertion was located at 41% + or - 3% and 52% + or - 3% of the tibial diameter from the anterior border for the AMB and PLB, respectively. The geometric centers of the tibial insertions in axial view were x = 52% + or - 2% and y = 37% + or - 3% for the AMB and x = 50% + or - 2% and y = 48% + or - 3% for the PLB., Conclusion: The insertion site characteristics of the AMB and PLB can be evaluated by predefined reconstructions of computed tomography scans. Clinical relevance These results can serve as orientation landmarks for intra- and postoperative radiographic control and fluoroscopic-based navigation.

The optimal technique of posterior cruciate ligament (PCL) reconstruction is still controversial. Besides different parameters as surgical technique and graft choice, the exact anatomic placement of the graft is essential for successful reconstruction of the PCL. For intraoperative control and postoperative radiological evaluation of the anatomical placement of the anterolatelateral (ALB) and posteromedial bundle (PMB) of the PCL, the radiological localization of both functional bundles of the PCL has yet to be determined. Therefore, in this descriptive laboratory study, the insertion sites of the ALB and PMB of the PCL on the femur and the common tibial insertion site were macroscopically identified and marked with copper wires in 16 human cadaver specimens. Radiological evaluation of the femoral insertion sites of the ALB and PMB in AP full extension and true lateral radiography was performed using an angle segment transformation based on the tangent of the femoral condyles and a modified reticule system of the quadrant method, respectively. On the tibial site, the footprint of the PCL was defined as ratios of the geometric insertion site with respect to the mediolateral and sagittal diameter of the tibia in AP and true lateral radiography. Femorally, the geometric insertion points of the ALB and PMB were located on the reticule at x = 62 +/- 3%/y = 16 +/- 6% and x = 51 +/- 5%/y = 35 +/- 7%, respectively; the angle segments for the PMB were between 40 +/- 5 degrees and 56 +/- 6 degrees and for the ALB were between 56 +/- 6 degrees and 76 +/- 7 degrees. Tibially, the common insertion point of the PCL was located at 51 +/- 2% of the mediolateral diameter of the tibial plateau with respect to the lateral border and 13 +/- 2% inferiorly to the medial tibial plateau with respect to the sagittal diameter of the tibial plateau. In conclusion, the knowledge of the anatomical insertion sites of the PCL in standardized radiography may help the orthopaedic surgeon for correct intraoperative placement and postoperative evaluation of the tunnel placement. In addition, the data might be a useful tool for fluoroscopic-based navigation in PCL reconstruction.

In general, dislocations of the long head of the biceps tendon are associated with partial or complete rotator cuff rupture on the side of the affected shoulder. We report about a patient with bilateral fixed and painless dislocation of the tendon of the long biceps head. By using functional ultrasound, correct diagnosis was facilitated and accelerated.

Purpose: This study was conducted to investigate the feasibility of laparoscopic resection of rectal cancer and to compare early outcome data with the results of the conventional technique., Methods: From January 1996 to March 2002, 435 patients with primary rectal cancer were operated on at our institution. Low-risk, small rectal tumors treatable by local excision, rectal cancer recurrences, and emergency cases were excluded from the analysis. Three hundred thirty-four patients were operated on by the conventional open approach. One hundred one selected patients underwent surgery by the laparoscopic technique., Results: Because of the selection process, significantly more patients with early tumor stages were operated on by laparoscopy. There were no differences in mean operation time, morbidity, mortality, or the anastomotic leakage rate; however, the need for intraoperative transfusion, mean stay in the intensive care unit, and length of hospital stay were reduced significantly., Conclusions: In terms of the intraoperative and early postoperative course, the laparoscopic resection of rectal cancer in a selected cohort of patients compares favorably with the open technique. Because follow-up time is limited to date, only very preliminary information can be given on tumor-related outcome data. However, these preliminary data appear to suggest that rectal cancer resection can be performed by laparoscopy in accordance with established principles of cancer therapy and that port-site metastases are not a relevant clinical problem. Prospective, randomized trials are required to determine whether the laparoscopic approach will play a significant role in the treatment of rectal cancer in the future.

The aim of this study was to evaluate the clinical use of a new three-dimensional mapping system as a guide for catheter ablation of ectopic atrial tachycardia. A series of 42 consecutive patients with drug refractory ectopic atrial tachycardia was studied in a prospective observational trial with the electroanatomic mapping system CARTO. The arrhythmogenic focus was found in the right atrium in 30 patients and in the left atrium in 12 patients. The construction of a complete electroanatomic map of the right or left atrium was possible in 37 of 42 consecutive patients with ectopic atrial tachycardia. Mean activation time of the right atrium, including the proximal coronary sinus, was 94 +/- 25 ms for right atrial tachycardias; left atrial activation time during left atrial tachycardias was 86 +/- 17 ms. Average mapping time was 30 minutes for right atrial tachycardias and 22 minutes for left atrial tachycardias, allowing the collection of 86 +/- 50 and 65 +/- 28 catheter positions, respectively. The size of the area of earliest atrial activation calculated from the electroanatomic map amounted to 0.6 +/- 0.4 cm2 in right atrial tachycardias and 1.0 +/- 0.9 cm2 in left atrial tachycardias. In the right atrium the most common locations of the 33 arrhythmogenic foci in 30 patients were the high or mid-lateral right atrium (n = 10) and the inferoparaseptal region near the coronary sinus ostium (n = 7). Ectopic left atrial foci were most commonly located in an inferior position near the mitral annulus (n = 5) and in proximity to the ostium of the pulmonary veins (n = 4). Biatrial electroanatomic mapping allowed visualization of earliest right atrial activation during left atrial tachycardia at the high interatrial septum or near the coronary sinus ostium. Catheter ablation was successful in 85% of right atrial tachycardias and 82% of left atrial tachycardias. In patients with ectopic atrial tachycardia electroanatomic mapping is a safe and feasible technique that allows three-dimensional visualization of the automatic focus in a precise anatomic reconstruction of the atria. This novel mapping technology facilitates catheter ablation of complex ectopic atrial tachycardia.

Unlabelled: Prerequisite for succesful radiofrequency catheter ablation of tachycardias is the exact mapping during the electrophysiological study. The new mapping system CARTO allows a three-dimensional color-coded electroanatomic map of impulse propagation using electromagnetic technology. The aim of this study was to determine the feasibility and safety of the new electromagnetic mapping technology CARTO for atrial tachycardias., Results: Electrophysiologic study and CARTO mapping was performed in 38 atrial tachycardias. The mapping procedure took 26 +/- 23 min. We created 33 maps within the right atrium and 5 maps within the left atrium with a mean of 74 +/- 38 different catheter positions. The mechanism was determined as reentrant in 9, junctional in 1 and focal in 28 tachycardias. In focal tachycardias the tachycardia cycle length (CL) and the total atrial activation time (AT) were clearly different (352 +/- 98 ms vs 99 +/- 25 ms). Reentrant tachycardias had a comparable CL and AT (236 +/- 44 ms vs 240 +/- 56 ms). In 83% of the focal tachycardias and in 67% of the reentrant tachycardias, ablation was performed successfully. No complications occured., Conclusion: The electroanatomic mapping system allows high resolution visualization of electrical activity and may therefore improve precision and simplify the determination of the arrhythmogenic substrate during tachycardias for successful catheter ablation.