How do we apply video-assisted retroperitoneal necrosectomy with minimal access?

The conservative treatment of acute necrotizing pancreatitis has greatly improved due to broad antibiotic treatment and improved organ support in intensive care units. Nevertheless, infected necrosis or persistent multi-organ dysfunction are predictors of poor outcome. In these patients, there is still a need to perform necrosectomy. Open surgery results in extensive operative trauma and is associated with high morbidity and mortality. Therefore, several minimally invasive techniques have been developed recently. Retroperitoneal necrosectomy has been shown to be safe and to reduce morbidity and mortality compared to the open procedure.

The location of paravertebral catheters placed using the landmark technique

The aim of this prospective clinical study was to evaluate the location of paravertebral catheters that were placed using the classical landmark puncture technique and to correlate the distribution of contrast dye injected through the catheters with the extent of somatic block. Paravertebral catheter placement was attempted in 31 patients after video-assisted thoracic surgery. In one patient, an ultrasound-guided approach was chosen after failed catheter placement using the landmark method. A fluoroscopic examination in two planes using contrast dye was followed by injection of local anaesthetic and subsequent clinical testing of the extent of the anaesthetised area. In nine patients (29%), spread of contrast dye was not seen within the paravertebral space as intended. Misplaced catheters were in the epidural space (three patients), in the erector spinae musculature (five patients), and in the pleural space (one patient). There was also a discrepancy between the radiological findings and the observed distribution of loss of sensation. We have demonstrated an unacceptably high misplacement rate of paravertebral catheters using the landmark method. Additional research is required to compare the efficacy and safety of continuous paravertebral block using ultrasound-guided techniques or surgical inserted catheters.

Emphysema and secondary pneumothorax in young adults smoking cannabis

BACKGROUND: We observed a remarkable increase in the number of young patients who presented with lung emphysema and secondary spontaneous pneumothorax (SSP) at our institution for over a period of 30 months; most of them have a common history of marijuana abuse. STUDY DESIGN: Retrospective case series. METHODS: Seventeen young patients presented with spontaneous pneumothorax with bullous lung emphysema were systematically evaluated over a period of 30 months. All were regular marijuana smokers. Clinical history, chest X-ray, CT-scan, lung function test, and laboratory and histological examinations were assessed. We compared the findings of this group (group I) with the findings of non-marijuana smoking patients (group II) in the same period. The findings of this series were also compared with the findings of 75 patients presented with pneumothorax in a previous period from January 2000 till March 2002 (group III). RESULTS: In group I, there were 17 patients: the median age of the patients was 27 years (range 19-43 years), 16 males and 1 female. All were living in Switzerland. All but one smoked marijuana daily for a mean of 8.8 years and tobacco for 11.8 years. CT-scan showed multiple bullae at the apex or significant bullous emphysema with predominance in the upper lobes only in two patients. Only two patients had reduced forced first second expiratory volume (FEV1) and one reduced vital capacity (VC) below the predicted 50%. This correlated with the subjectively asymptomatic condition of the patients. All but two patients were treated by video-assisted thoracoscopic surgery (VATS) for prevention of relapsing pneumothorax. Histology showed severe lung emphysema, inflammation, and heavily pigmented macrophages. In group II, there were 85 patients: there were 78 males, the median age was 24 years (range 17-40 years), 74 patients smoked tobacco for 13.4 years but no marijuana. CT-scan in 72 patients showed only small bullae at the apex but no significant emphysema; other clinical, laboratory, and histopathological findings showed no significant difference in group I. In group III, there were 75 patients: there were 71 males and 4 females. Mean age was 25 years (range 16-46 years). Six smoked marijuana daily for a mean of 3.2 years, and 62 smoked tobacco for 14 years. CT-scan done in 59 patients showed few small bullae at the apex but no significant lung emphysema. The presence of lung emphysema on CT-scan in group I was significantly different than in groups II and III (p=0.14). No significant difference was found among all groups in the form of clinical, laboratory, and histopathological findings. CONCLUSIONS: In case of emphysema in young individuals, marijuana abuse has to be considered in the differential diagnosis. The period of marijuana smoking seems to play an important role in the development of lung emphysema. This obviously quite frequent condition in young and so far asymptomatic patients will have medical, financial, and ethical impact, as some of these patients may be severely handicapped or even become lung transplant candidates in the future.

[The role of thoracoscopy in paediatric spontaneous pneumothorax]

Spontaneous pneumothorax in children is an emergency. A rapid and structured treatment is necessary. Indicating clinical signs are dyspnoea with unilateral reduced breath sounds and hypersonic percussion note. Chest x-ray confirms diagnosis. CT scan shows detailed information's of pathological changes in lung tissue and offers important considerations for the therapy. Today video assisted thoracoscopic surgery (VATS) takes a central role in the treatment of spontaneous pneumothorax. Thoracoscopy completes diagnosis detecting the pathologies, which were missed in imaging procedures. Definitive surgical treatment is performed simultaneously in the same anaesthesia.

Robotic lobectomy: tips, pitfalls and troubleshooting

The robotic approach in thoracic surgery has rapidly gained popularity in recent years. As with the introduction of any new technology, this warrants not only adaptation of the operative technique itself, but also the evolution of appropriate troubleshooting strategies. A selected number of helpful tips and technical procedural manoeuvres have been compiled to prevent intraoperative problems, as well as to overcome challenging situations that can arise during robotic lobectomies. In robotic surgery, as opposed to open surgery or video-assisted thoracic surgery, these tips serve an important purpose for the operating surgeon, as well as the entire surgical team involved in the procedure. All the assembled recommendations have proved their effectiveness and have been successfully used by the authors in many procedures. Furthermore, these manoeuvres have been found to be of great importance in the training and proctoring of thoracic surgeons, fellows and residents (bed-side assistants). This guide of clearly arranged tips and troubleshooting strategies offers surgeons a useful tool to overcome difficult situations in robotic lobectomy and preferably improve the reproducibility and safety of their procedures.

ERS task force statement: diagnosis and treatment of primary spontaneous pneumothorax.

Primary spontaneous pneumothorax (PSP) affects young healthy people with a significant recurrence rate. Recent advances in treatment have been variably implemented in clinical practice. This statement reviews the latest developments and concepts to improve clinical management and stimulate further research.The European Respiratory Society's Scientific Committee established a multidisciplinary team of pulmonologists and surgeons to produce a comprehensive review of available scientific evidence.Smoking remains the main risk factor of PSP. Routine smoking cessation is advised. More prospective data are required to better define the PSP population and incidence of recurrence. In first episodes of PSP, treatment approach is driven by symptoms rather than PSP size. The role of bullae rupture as the cause of air leakage remains unclear, implying that any treatment of PSP recurrence includes pleurodesis. Talc poudrage pleurodesis by thoracoscopy is safe, provided calibrated talc is available. Video-assisted thoracic surgery is preferred to thoracotomy as a surgical approach.In first episodes of PSP, aspiration is required only in symptomatic patients. After a persistent or recurrent PSP, definitive treatment including pleurodesis is undertaken. Future randomised controlled trials comparing different strategies are required.

EACTS expert consensus statement for surgical management of pleural empyema

Pleural infection is a frequent clinical condition. Prompt treatment has been shown to reduce hospital costs, morbidity and mortality. Recent advances in treatment have been variably implemented in clinical practice. This statement reviews the latest developments and concepts to improve clinical management and stimulate further research. The European Association for Cardio-Thoracic Surgery (EACTS) Thoracic Domain and the EACTS Pleural Diseases Working Group established a team of thoracic surgeons to produce a comprehensive review of available scientific evidence with the aim to cover all aspects of surgical practice related to its treatment, in particular focusing on: surgical treatment of empyema in adults; surgical treatment of empyema in children; and surgical treatment of post-pneumonectomy empyema (PPE). In the management of Stage 1 empyema, prompt pleural space chest tube drainage is required. In patients with Stage 2 or 3 empyema who are fit enough to undergo an operative procedure, there is a demonstrated benefit of surgical debridement or decortication [possibly by video-assisted thoracoscopic surgery (VATS)] over tube thoracostomy alone in terms of treatment success and reduction in hospital stay. In children, a primary operative approach is an effective management strategy, associated with a lower mortality rate and a reduction of tube thoracostomy duration, length of antibiotic therapy, reintervention rate and hospital stay. Intrapleural fibrinolytic therapy is a reasonable alternative to primary operative management. Uncomplicated PPE [without bronchopleural fistula (BPF)] can be effectively managed with minimally invasive techniques, including fenestration, pleural space irrigation and VATS debridement. PPE associated with BPF can be effectively managed with individualized open surgical techniques, including direct repair, myoplastic and thoracoplastic techniques. Intrathoracic vacuum-assisted closure may be considered as an adjunct to the standard treatment. The current literature cements the role of VATS in the management of pleural empyema, even if the choice of surgical approach relies on the individual surgeon's preference.

Real-Time Multimodal Retinal Image Registration for a Computer Assisted Laser Photocoagulation System

An algorithm for the real-time registration of a retinal video sequence captured with a scanning digital ophthalmoscope (SDO) to a retinal composite image is presented. This method is designed for a computer-assisted retinal laser photocoagulation system to compensate for retinal motion and hence enhance the accuracy, speed, and patient safety of retinal laser treatments. The procedure combines intensity and feature-based registration techniques. For the registration of an individual frame, the translational frame-to-frame motion between preceding and current frame is detected by normalized cross correlation. Next, vessel points on the current video frame are identified and an initial transformation estimate is constructed from the calculated translation vector and the quadratic registration matrix of the previous frame. The vessel points are then iteratively matched to the segmented vessel centerline of the composite image to refine the initial transformation and register the video frame to the composite image. Criteria for image quality and algorithm convergence are introduced, which assess the exclusion of single frames from the registration process and enable a loss of tracking signal if necessary. The algorithm was successfully applied to ten different video sequences recorded from patients. It revealed an average accuracy of 2.47 ± 2.0 pixels (∼23.2 ± 18.8 μm) for 2764 evaluated video frames and demonstrated that it meets the clinical requirements.

Retinal slit lamp video mosaicking

Purpose To this day, the slit lamp remains the first tool used by an ophthalmologist to examine patient eyes. Imaging of the retina poses, however, a variety of problems, namely a shallow depth of focus, reflections from the optical system, a small field of view and non-uniform illumination. For ophthalmologists, the use of slit lamp images for documentation and analysis purposes, however, remains extremely challenging due to large image artifacts. For this reason, we propose an automatic retinal slit lamp video mosaicking, which enlarges the field of view and reduces amount of noise and reflections, thus enhancing image quality. Methods Our method is composed of three parts: (i) viable content segmentation, (ii) global registration and (iii) image blending. Frame content is segmented using gradient boosting with custom pixel-wise features. Speeded-up robust features are used for finding pair-wise translations between frames with robust random sample consensus estimation and graph-based simultaneous localization and mapping for global bundle adjustment. Foreground-aware blending based on feathering merges video frames into comprehensive mosaics. Results Foreground is segmented successfully with an area under the curve of the receiver operating characteristic curve of 0.9557. Mosaicking results and state-of-the-art methods were compared and rated by ophthalmologists showing a strong preference for a large field of view provided by our method. Conclusions The proposed method for global registration of retinal slit lamp images of the retina into comprehensive mosaics improves over state-of-the-art methods and is preferred qualitatively.