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Lynch syndrome (LS), an autosomal dominant cancer syndrome, is the most common cause of hereditary colon cancer. Currently, however, less than 5% of patients with LS have been identified. Reflex-testing programs (in which tumors of patients with colorectal cancer are routinely evaluated for LS) have been proposed for better identification of affected individuals, yet the uptake of these programs within health care systems is limited. This study explored the structure, implementation challenges, and future directions of existing international population-based reflex LS testing programs. The study identified existing reflex-testing LS programs through the current literature and through a qualitative sampling approach. Key informants from each program were interviewed. Qualitative data were analyzed using a grounded theory analytic technique approach. The interviews were completed by 26 informants across seven identified programs. Three key themes were identified: (1) tension between a program imposed on stakeholders (a top-down approach) versus initiation of the program at the stakeholder level (bottom-up approach), (2) identification of pathologists as drivers of program success, and (3) strategies to optimize possible LS patients liaising with genetic counselors. Barriers to successful implementation included lack of stakeholder engagement and concerns regarding cost. Facilitators included strong administration to coordinate patient tracking and flexibility during the implementation process. Existing reflex-testing LS programs have varying structures, standards, and protocols. Program design can have a direct effect on the uptake of genetic testing. These are important considerations in the large-scale planning of LS reflex-testing programs within health systems.

The purpose of this study was to explore resident perceptions regarding four current models for teaching laparoscopic suturing and to assess the current quality of training in advanced minimally invasive surgical techniques at an academic teaching center.This study included 14 senior general surgery residents (PGY 3-5) participating in a workshop in advanced laparoscopy. Four training tools were used in the course curriculum: the Fundamentals of Laparoscopic Surgery (FLS) black box suturing model, a synthetic Nissen fundoplication model, a virtual reality (VR) simulator suturing task, and a porcine jejuno-jejunostomy model. After the workshop, residents were asked to complete a questionnaire relating to their experience with laparoscopic surgery, and their opinions regarding the four training models. Model rank was analyzed with one-way ANOVA, and χ(2) analysis with Fisher's exact test was used to analyze model effectiveness.The majority of residents had strong experience in basic laparoscopic cases such as cholecystectomy and appendectomy; however, few participants had experience in advanced cases. As a group, the residents ranked the porcine model first (average 1.6, median 1), followed by the synthetic Nissen model (average 2.0, median 2), the FLS model (average 2.5, median 3), and the VR trainer (average 3.2, median 4). Finally, each resident was asked to rate the four models individually with respect to their educational value. Scores were on a Likert scale from 1 to 5. Nine of 11 (81.8%) residents rated the animal model as "extremely helpful" while only 3 of 14 (21.4%) participants rated the VR model as "extremely helpful" (p = 0.048).This study demonstrates that operative experience in advanced laparoscopy for senior residents is suboptimal. Residents learning this skill in a simulated environment prefer animal or video-trainers as teaching models rather than virtual reality. This has implications when designing a curriculum for advanced endoscopy.

The subthalamic nucleus (STN) is an important component of the basal ganglia (BG) and plays a major role in the pathogenesis of Parkinson's disease (PD). Hyperactivity of STN as a consequence of the loss of dopaminergic inputs to the BG is believed to be a major factor in producing the motor symptoms of PD. High-frequency (HF) deep brain stimulation (DBS) of the STN has recently become an important treatment in PD patients where medications no longer provide satisfactory therapy. However, the mechanisms underlying DBS therapy are unknown, and there is seemingly conflicting data suggesting inhibition or excitation of STN neurons. This study directly examined the effects of stimulation in STN on the activity of STN neurons in PD patients during functional stereotactic mapping prior to insertion of DBS electrodes. Electrical stimulation in STN was investigated in twelve PD patients by recording the neural activity of a cell in STN with one electrode while applying current pulses through a second electrode located about 600 microm away. Stimulation at high frequencies (100-300 Hz) was found to produce inhibition following the stimulus train in 42% of the 60 cells tested. Inhibition during the train was seen in 13 of 15 neurons where it was possible to detect such activity. Furthermore, in 44% of the cases where HF stimulation produced inhibition there was an early inhibition followed by rebound excitation and a further inhibitory period, suggesting that the inhibitions observed are due to hyperpolarization. In eight of the 25 neurons inhibited by HF stimulation, the effects of single stimuli were determined and revealed that in seven of these there was an inhibitory period of 15-20 ms following each stimulus. Thus, the present findings suggest that local HF stimulation inhibits many STN neurons. However, these studies could not determine whether the stimulus also directly excited the cell and/or its axon, but other recent findings suggest that this is likely the case. Therefore, the overall effects of DBS stimulation in STN are likely to be inhibition of intrinsic and synaptically mediated activity, and its replacement by regular high-frequency firing.