Porcine intact and wounded skin responses to atmospheric nonthermal plasma.

Thermal plasma is a valued tool in surgery for its coagulative and ablative properties. We suggested through in vitro studies that nonthermal plasma can sterilize tissues, inactive pathogens, promote coagulation, and potentiate wound healing. The present research was undertaken to study acute toxicity in porcine skin tissues. We demonstrate that floating electrode-discharge barrier discharge (FE-DBD) nonthermal plasma is electrically safe to apply to living organisms for short periods. We investigated the effects of FE-DBD plasma on Yorkshire pigs on intact and wounded skin immediately after treatment or 24h posttreatment. Macroscopic or microscopic histological changes were identified using histological and immunohistochemical techniques. The changes were classified into four groups for intact skin: normal features, minimal changes or congestive changes, epidermal layer damage, and full burn and into three groups for wounded skin: normal, clot or scab, and full burn-like features. Immunohistochemical staining for laminin layer integrity showed compromise over time. A marker for double-stranded DNA breaks, γ-H2AX, increased over plasma-exposure time. These findings identified a threshold for plasma exposure of up to 900s at low power and <120s at high power. Nonthermal FE-DBD plasma can be considered safe for future studies of external use under these threshold conditions for evaluation of sterilization, coagulation, and wound healing.

Automatic retrieval of bone fracture knowledge using natural language processing.

Natural language processing (NLP) techniques to extract data from unstructured text into formal computer representations are valuable for creating robust, scalable methods to mine data in medical documents and radiology reports. As voice recognition (VR) becomes more prevalent in radiology practice, there is opportunity for implementing NLP in real time for decision-support applications such as context-aware information retrieval. For example, as the radiologist dictates a report, an NLP algorithm can extract concepts from the text and retrieve relevant classification or diagnosis criteria or calculate disease probability. NLP can work in parallel with VR to potentially facilitate evidence-based reporting (for example, automatically retrieving the Bosniak classification when the radiologist describes a kidney cyst). For these reasons, we developed and validated an NLP system which extracts fracture and anatomy concepts from unstructured text and retrieves relevant bone fracture knowledge. We implement our NLP in an HTML5 web application to demonstrate a proof-of-concept feedback NLP system which retrieves bone fracture knowledge in real time.

Safety of ultrasound-guided fine needle aspiration biopsy of neck lesions in patients taking antithrombotic/anticoagulant medications.

We examined records of patients who underwent ultrasound-guided fine needle aspiration biopsy (USGFNAB) of neck lesions to determine whether there was a significantly increased incidence of bleeding complications in patients on antithrombotic and/or anticoagulant (AT/AC) medications compared to patients not receiving AT/AC therapy. Our institutional review board approved this Health Insurance Portability and Accountability Act-compliant retrospective examination of patients' medical data without requiring informed consent. The records of 593 patients (422 women and 171 men ranging from 18 to 91 years of age) who underwent USGFNAB of 788 total neck lesions over an 18-month period were reviewed to determine AT/AC medication used and evidence of USGFNAB-related bleeding complications. Of these, 144 patients (24.3%) were taking one or more AT/AC medications including aspirin, clopidogrel, heparin, and warfarin. The χ2 test was used to assess statistically significant differences in the incidence of USGFNAB-related bleeding complications between patients who were on daily AT/AC medications (test group) and patients who were not (control group). Six USGFNAB-related hematomas (1.0%) occurred. Two hematomas developed in patients on AT/AC medications, and 4 hematomas developed in patients who did not take AT/AC medications (χ = 0.27, df = 1, P = 0.603). This study shows no statistically significant difference in the incidence of hematoma formation after USGFNAB of neck lesions in patients taking AT/AC medications compared to patients not taking AT/AC medications. On the basis of these data, there is no benefit, with regard to incidence of bleeding complications, to discontinuing AT/AC medications in patients undergoing USGFNAB of neck masses.

Evaluation of negation and uncertainty detection and its impact on precision and recall in search.

Radiology reports contain information that can be mined using a search engine for teaching, research, and quality assurance purposes. Current search engines look for exact matches to the search term, but they do not differentiate between reports in which the search term appears in a positive context (i.e., being present) from those in which the search term appears in the context of negation and uncertainty. We describe RadReportMiner, a context-aware search engine, and compare its retrieval performance with a generic search engine, Google Desktop. We created a corpus of 464 radiology reports which described at least one of five findings (appendicitis, hydronephrosis, fracture, optic neuritis, and pneumonia). Each report was classified by a radiologist as positive (finding described to be present) or negative (finding described to be absent or uncertain). The same reports were then classified by RadReportMiner and Google Desktop. RadReportMiner achieved a higher precision (81%), compared with Google Desktop (27%; p < 0.0001). RadReportMiner had a lower recall (72%) compared with Google Desktop (87%; p = 0.006). We conclude that adding negation and uncertainty identification to a word-based radiology report search engine improves the precision of search results over a search engine that does not take this information into account. Our approach may be useful to adopt into current report retrieval systems to help radiologists to more accurately search for radiology reports.

Initial surgeon training for single port access surgery: our first year experience.

BACKGROUND: We have developed a single port access (SPA) surgical technique that allows for procedures to be done through a single umbilical port incision <20 mm in length. For a new approach to be universally beneficial, it needs to be easily learned and applied. METHODS: Single port access abdominal procedures are performed through one umbilical incision where skin and soft tissue flaps are raised from the underlying fascia to allow insertion of up to 4 instruments. Fifty surgeons with varying degrees of laparoscopic training participated in SPA training programs at Drexel University to learn and apply the SPA technique through participation in an animate (porcine) laboratory. RESULTS: All surgeons successfully performed the SPA access technique without difficulty and completed the cholecystectomy in <55 minutes (average, 42). Eight surgeons successfully performed placement of a cholangiogram catheter. All recognized the value of a formal training symposium to learn SPA techniques before performing SPA procedures in their practice. CONCLUSIONS: The SPA technique has been successfully shown to be an approach that is easily learned and accomplished. We believe this is a necessary and important bridge towards proficiency in performing SPA procedures in clinical patients.

Single-port-access (SPA) cholecystectomy: a multi-institutional report of the first 297 cases.

BACKGROUND: An important aspect of a new surgical technique is whether it can be performed by other surgeons in other institutions. The authors report the first 297 cases in a multi-institutional and multinational review of laparoscopic cholecystectomy performed via a single portal of entry. METHODS: Data were collected retrospectively for the initial patients undergoing single-port cholecystectomy by 13 surgeons who performed these procedures in their institutions after training by the authors. The review included operative time, blood loss, incision length, length of hospital stay (LOS), necessary additional trocars, and other parameters important to cholecystectomy. A database of all the single-port-access (SPA) surgeries performed by the surgeons included demographic and procedural details, LOS, complications, and initial follow-up data. RESULTS: To date, 297 single-port cholecystectomies have been performed for a variety of diagnoses, primarily cholelithiasis. The average operative time was 71 min, and the average LOS was 1-2 days. The average blood loss was minimal. The use of additional port sites outside the umbilicus occurred in 34 of the cases. Of the 35 intraoperative cholangiograms performed, 34 were successful. No significant complications occurred except for seromas and minor postoperative wound infections. These results are comparable with those for standard multiport cholecystectomy. In addition, no access site hernias (ASH) occurred. CONCLUSIONS: The findings demonstrate that SPA surgery is an alternative to multiport laparoscopy with fewer scars and better cosmesis. One factor affecting the rate for adoption of SPA surgery among other surgeons is the reproducibility of this new procedure. Although this study had insufficient data to determine fully the benefits of SPA surgery, the feasibility of this procedure with safe, acceptable results was demonstrated in this initial large series across multinational institutions.

Single Port Access (SPA) laparoscopic ventral hernia repair: initial report of 30 cases.

BACKGROUND: Laparoscopic ventral hernia repair has been demonstrated to be an acceptable and successful technique. Aside from similar, albeit fewer, complications compared to open hernia repair, the laparoscopic technique has the additional complication of port site hernia to its follow-up criteria. Our initial experience with reduced port surgery in hernias was described as a two-port one-stitch repair technique in 2002. We initially applied our Single Port Access (SPA) technique to ventral hernia repairs and reported it at the American Hernia Society meeting in 2008. Now we present the first 30 cases, some with 6-24-month follow-up. METHODS: The charts of 30 patients undergoing surgery for primary and recurrent ventral hernias employing the SPA technique were reviewed. The SPA technique was applied through a 1.0-1.6-cm incision remote from and lateral to the hernia location in the abdominal wall. Polypropylene-based coated mesh and non-fascial fixation were used in all cases. RESULTS: All procedures were completed via the SPA technique. Operative time, length of stay, and estimated blood loss were acceptable. The size of mesh placed ranged from 81 to 500 cm(2). Postoperative seromas were observed and all resolved spontaneously. There have been no wound infections or port site hernias during the 6-24-month follow-up period. There have been no recurrent hernias at the primary site. CONCLUSION: We have successfully demonstrated the applicability of Single Port Access surgery for ventral hernia repair. In our initial series we performed this procedure on smaller hernias but have now begun applying it to larger repairs.

CT pulmonary angiography: quantification of pulmonary embolus as a predictor of patient outcome--initial experience.

PURPOSE: To determine whether quantification of pulmonary embolus (PE) with computed tomographic (CT) pulmonary angiography by using a standardized index is a predictor of patient outcome. MATERIALS AND METHODS: Multi-detector row CT was performed in 59 hospitalized patients (mean age, 61 years; age range, 22-89 years). PE was identified retrospectively by two radiologists who were blinded to patient outcome. A pulmonary arterial obstruction index was derived for each set of images on the basis of embolus size and location. By using logistic regression, PE indexes were compared with patient outcome-survival or death-to determine if there was a correlation between PE volume and survival. RESULTS: The PE index is a significant predictor of patient outcome (P =.002). One of 53 patients (1.9%) with an index of less than 60% died. Cause of death was end-stage malignancy. Five of six patients (83%) with an index of 60% and higher died. All five deaths were related to the presence of PE. The one survivor with a PE index higher than 60% received thrombolytic therapy. By using a cutoff of 60%, the PE index was used to identify 52 of 53 (98%) patients who survived and five of six (83%) patients who died. CONCLUSION: Preliminary evidence suggests that quantification of clot with CT pulmonary angiography is an important predictor of patient death in the setting of PE.