Discover the most talked about and latest scientific content & concepts.

Concept: Invasive


BACKGROUND: A few lineages of Group A streptococci (GAS) have been associated with a reemergence of severe invasive streptococcal disease in developed countries. However, the majority of the comparisons between invasive and non-invasive GAS isolates have been performed for collections of reduced genetic diversity or relied on limited typing information to distinguish clones. We characterized by several typing methods and compared a collection of 160 isolates recovered from normally sterile sites with 320 isolates associated with pharyngitis and recovered in the same time period in Portugal. RESULTS: Although most of the isolates belonged to clones that were equally prevalent in invasive infections and pharyngitis, we identified markers of invasiveness, namely the emm types 1 and 64, and the presence of the speA and speJ genes. In contrast, emm4, emm75, and the ssa and speL/M genes were significantly associated with pharyngitis. There was a strong agreement between the emm type, the superantigen (SAg) genes and the clusters defined by pulsed-field gel electrophoresis (PFGE) profiling. Therefore, combinations of particular emm types and SAg genes frequently co-occurred in the same PFGE cluster, but there was no synergistic or antagonistic interaction between them in determining invasiveness. Only macrolide-susceptible PFGE clones were significantly associated with invasive infections or pharyngitis, while the clones of resistant isolates sharing all other molecular properties analyzed were equally prevalent in the two groups of isolates. CONCLUSIONS: This study confirmed the importance of the widely disseminated emm1-T1-ST28 clone in invasive infections but also identified other clones linked to either invasive infections (emm64-ST164) or pharyngitis (emm4-T4-ST39), which may be more limited in their temporal and geographical spread. Clonal properties like some emm types or SAg genes were associated with disease presentation, highlighting the importance of bacterial genetic factors to the outcome of GAS infections, although other, yet unidentified factors may also play an important role.

Concepts: Gene, Genetics, Bacteria, Virus, Streptococcus, Invasive, Invasiveness of surgical procedures, Group A streptococcal infection


Use of robotic systems for minimally invasive surgery has rapidly increased during the last decade. Understanding the causes of adverse events and their impact on patients in robot-assisted surgery will help improve systems and operational practices to avoid incidents in the future.

Concepts: Surgery, Minimally invasive, Invasive, Invasiveness of surgical procedures


Untethered small-scale (from several millimetres down to a few micrometres in all dimensions) robots that can non-invasively access confined, enclosed spaces may enable applications in microfactories such as the construction of tissue scaffolds by robotic assembly, in bioengineering such as single-cell manipulation and biosensing, and in healthcare such as targeted drug delivery and minimally invasive surgery. Existing small-scale robots, however, have very limited mobility because they are unable to negotiate obstacles and changes in texture or material in unstructured environments. Of these small-scale robots, soft robots have greater potential to realize high mobility via multimodal locomotion, because such machines have higher degrees of freedom than their rigid counterparts. Here we demonstrate magneto-elastic soft millimetre-scale robots that can swim inside and on the surface of liquids, climb liquid menisci, roll and walk on solid surfaces, jump over obstacles, and crawl within narrow tunnels. These robots can transit reversibly between different liquid and solid terrains, as well as switch between locomotive modes. They can additionally execute pick-and-place and cargo-release tasks. We also present theoretical models to explain how the robots move. Like the large-scale robots that can be used to study locomotion, these soft small-scale robots could be used to study soft-bodied locomotion produced by small organisms.

Concepts: Surgery, Temperature, Minimally invasive, Liquid, Invasive, Invasiveness of surgical procedures, Robotics, Robot


OBJECTIVE:: Computer 3D navigation (3D NAV) techniques in spinal instrumentation can theoretically improve screw placement accuracy and reduce injury to critical neurovascular structures, especially in complex cases. In this series, we analyze the results of 3D NAV in pedicle screw placement accuracy, screw outer diameter, and case complexity in comparison to screws placed with conventional lateral fluoroscopy. METHODS:: Pedicle screws placed in the cervical, thoracic or lumbar spine using either standard lateral fluoroscopy or 3D NAV employing isocentric fluoroscopy were retrospectively analyzed. The accuracy of each individual screw was graded on a 4-tiered classification system. Screw and pedicle diameter measurements were also made in both cohorts, and case complexity was compared between the two cohorts. Complex cases were defined as deformity surgery, re-do cases and minimally invasive surgery. RESULTS:: A total of 708 screws were placed under 3D NAV guidance and 726 screws were placed without stereotaxy. Eighty-eight percent of 3D NAV-guided pedicle screws were graded non-breach versus 82% of cases with lateral fluoroscopy (P<0.001). The ratio of screw/pedicle diameter was significantly larger in the 3D NAV cohort (0.71 vs. 0.63, P<0.05). 76% of 3D NAV cases had a pre-defined aspect of complexity, whereas 44% of non-3D NAV cases met criteria to be labeled complex (P<0.001). Re-operation occurred less frequently in 3D NAV cases than fluoroscopy-alone. CONCLUSIONS:: The use of 3D NAV was associated with improved screw placement accuracy, improved screw-to-pedicle diameter measurements, and was employed in cases with a higher degree of surgical complexity. We conclude that 3D NAV is a valuable tool in current spinal instrumentation, especially for more complex surgeries.

Concepts: Surgery, Vertebral column, Minimally invasive, Screw, Invasive, Screw thread, Screws


The realm of minimally invasive surgery now encompasses the majority of abdominal operations in the field of colorectal surgery. Diverticulitis, a common pathology seen in most colorectal practices, poses unique challenges to surgeons implementing laparoscopic surgery in their practices due to the presence of an inflammatory phlegmon and distorted anatomical planes, which increase the difficulty of the operation. Although the majority of colon resections for diverticulitis are still performed through a standard laparotomy incision, laparoscopic techniques are becoming increasingly common. A large body of literature now supports laparoscopic surgery to be safe and effective as well as to provide significant advantages over open surgery for diverticular disease. Here, we review the most current literature supporting laparoscopic surgery for elective and emergent treatment of diverticulitis.

Concepts: Surgery, Colon, Minimally invasive, Laparoscopic surgery, Invasive, Invasiveness of surgical procedures, Open surgery, Diverticulitis


Abstract Purpose: To evaluate the efficacy and safety of adjunctive mitomycin-c (MMC) during probing in adults with primary nasolacrimal duct (NLD) obstruction. Methods: This is a prospective, comparative, randomized interventional study. A total of 40 adult patients with unilateral epiphora caused by primary NLD obstruction were treated and evaluated. Lacrimal probing and irrigation with adjunctive MMC (1 mL of 0.2 mg/mL, once) in cases and only probing in controls were done. At the end of 3 months, subjective improvement in epiphora and patency on syringing were evaluated. Results: Complete subjective improvement in epiphora was found in 15% of cases as opposed to 0% in controls, at 3 months of follow-up. Moderate improvement was seen in 25% of cases as opposed to 5% of controls. Mild improvement was seen in 25% of cases as opposed to 35% in controls. The overall subjective improvement was seen in 65% of cases as opposed to 40% in controls. On syringing, NLD was patent in 30% of cases as opposed to 10% in controls at 3 months of follow-up, which was not significant. Conclusions: Use of intraoperative MMC improves the success of probing to some extent. Being a minimally invasive procedure, it can be tried in patients who refuse or are not systemically fit for undergoing dacryocystorhinostomy.

Concepts: Minimally invasive, Invasive, Invasiveness of surgical procedures, Tears, Nasolacrimal duct, Nasolacrimal canal


Robot-assisted surgery is gaining momentum as a new trend in minimally invasive surgery. With limited evidence supporting its use in place of the far less expensive conventional laparoscopic surgery, it has been suggested that marketing pressure is partly responsible for its widespread adoption. The impact of phrases that promote the novelty of robot-assisted surgery on patient decision making has not been investigated. We conducted a discrete choice experiment to elicit preference of partial colectomy technique for a hypothetical diagnosis of colon cancer. A convenience sample of 38 participants in an ambulatory general surgery clinic consented to participate. Each participant made 2 treatment decisions between robot-assisted surgery and conventional laparoscopic surgery, with robot-assisted surgery described as “innovative” and “state-of-the-art” in one of the decisions (marketing frame), and by a disclosure of the uncertainty of available evidence in the other (evidence-based frame). The magnitude of the framing effect was large with 12 of 38 subjects (31.6%, P = .005) selecting robot-assisted surgery in the marketing frame and not the evidence-based frame. This is the first study to our knowledge to demonstrate that words that highlight novelty have an important influence on patient preference for robot-assisted surgery and that use of more neutral language can mitigate this effect.

Concepts: Decision making, Participation, E-participation, Surgery, Cognition, Minimally invasive, Laparoscopic surgery, Invasive


Flexible flatfoot is the most prevalent condition seen in pediatric orthopedic clinics. It is characterized by an absence of the medial arch and a valgus position of the calcaneus. The purpose of the present study was to report on the results obtained in children treated using the calcaneo-stop procedure. A total of 410 flatfeet in 242 consecutive patients were treated using the calcaneo-stop procedure from January 1999 to March 2010 (10 years, 3 months) and were followed up to February 2012. The mean age at surgery was 11 (range 7 to 14) years, and the mean follow-up duration was 88 (range 14 to 157) months. A clinical evaluation, podoscopic examination, and radiologic assessment were performed in the participating patients preoperatively and at 6 months postoperatively. Of the 242 patients, 168 (69.42%) underwent bilateral foot surgery and 74 (30.58%) unilateral intervention, involving 33 right (44.6%) and 41 left (55.4%) feet. At follow-up, the outcome was satisfactory in 397 feet (96.83%); heel valgus was observed in only 12 feet (2.92%), and the footprint was normalized in 328 feet (80%). The calcaneo-stop procedure is a simple, reliable, and minimally invasive procedure for the treatment of pediatric flexible flatfoot. It allows alignment of the talus and calcaneus, restoring a proper foot arch.

Concepts: Foot, Minimally invasive, Invasive, Tarsus, Calcaneus, Arches of the foot, Flat feet, Unilateralism


BACKGROUND: Laparoscopic myomectomy (LM) has increased recently as treatment options for symptomatic uterine myomas for a patient who wants to preserve her uterus. However, adequate suture of the uterine defect is difficult in LM, even for an experienced surgeon. The most time-consuming step of LM is the suturing procedure. The suture material can tangle easily and disentanglement is time-consuming. We introduce a simple but highly effective instrument named “Puller” for continuous intracorporeal suturing in LM. METHODS: After completion of myoma enucleation, the operator sutures the uterine defect with suture material in continuous manner. The tip of “Puller” looks like a hook. During the suture, the first assistant inserts the “Puller” on the suprapubic site and sets the suture material on the hook and pulls it extracorporeally. After one stitch, the operator pulls the suture material intracorporeally, and then the first assistant pulls the sutured portion of the thread extracorporeally with “Puller” and holds the stitch to maintain the adequate tension during the repair. RESULTS: From January 2011 to October 2011, 88 patients who were diagnosed with uterine myoma underwent LM using “Puller” by a single surgeon. The mean diameter of the myoma was 6.8 ± 2.1 cm, and multiple myomas were observed in 46 cases (52.3 %). As a result, the mean operation time was 65.0 ± 22.1 min, the estimated blood loss was 173.9 ± 179.8 ml. Mean weight of removed myoma was 141.5 ± 105.7 g. Postoperative febrile morbidity (body temperature higher than 37.7 °C) was observed in 15 patients (17 %). However, no patients had conversion to laparotomy and needed blood transfusion. There were no major complications that required reoperation or readmission. CONCLUSIONS: Laparoscopic myomectomy can be performed easily and effectively by using the “Puller” technique with standard instruments. Additionally, this “Puller” technique could be adopted in all minimally invasive surgery needed running suture for hemostasis and closure.

Concepts: Blood, Uterus, Surgery, Minimally invasive, Surgical suture, Invasive, Abu al-Qasim al-Zahrawi, Catgut suture


Prolonged operative time (ORT) is often considered a drawback to minimally invasive surgery (MIS) due to increased morbidity. Limited data exist comparing long laparoscopic ORT to similar or shorter open ORT. This study aims to identify ORT when a minimally invasive procedure becomes inferior to its open counterpart. Minimally invasive and open total and partial nephrectomies, and nephroureterectomies were identified in the National Surgical Quality Improvement Program (NSQIP) from 2005-2012. Procedures were split into open and MIS and stratified into 4 ORT groups: 0-90 minutes, 91 minutes-3 hours, 3-6 hours, and ≥6 hours. 30-day mortality and morbidity were analyzed. Univariate analysis was performed using chi-square and Fishers Exact tests. Significant univariate results were tested using stepwise logistic regression, controlling for demographics, comorbidities, and preoperative treatments. 14,813 patients were identified. Both partial and total minimally invasive kidney procedures had significantly improved outcomes compared to open counterparts of similar ORT. In the total group, MIS had a lower rate of SSI’s, sepsis, pneumonia, return to OR and length of stay when compared to open procedures of the same duration. Length of hospital stay decreased in MIS regardless of operative time, except when comparing minimally invasive cases longer than 6 hours to open cases less than 90 minutes. Transfusion rates also significantly decreased in minimally invasive total nephrectomies. In the partial group, similar outcomes were seen with length of stay and infectious outcomes. Interestingly, transfusion was decreased in the open partial nephrectomy group when comparing cases less than 90 minutes to minimally invasive partials lasting 3-6 hours; otherwise there was no significant correlation with transfusion. Minimally invasive operations are less morbid than open operations of similar ORT. Longer and likely more complex laparoscopic procedures continue to provide a benefit when compared to shorter and possibly less complex open procedures. These data should be considered during a surgeon’s pre-operative and operative decision-making.

Concepts: Kidney, Surgery, Minimally invasive, Invasive, Invasiveness of surgical procedures, Nephrectomy, Open surgery, Minimally-invasive