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1.  Design and development of adapters for electromagnetic trackers to perform navigated laparoscopic radiofrequency ablation 
Laparoscopic radiofrequency ablation (RFA) is an accepted approach to treat unresectable liver tumours distinguishing itself from other techniques by combining minimal invasiveness and the advantages of a surgical approach. The major task of laparoscopic RFA is the accurate needle placement to achieve complete tumour ablation. The use of an ultrasound-based, laparoscopic online-navigation system could increase the safety and accuracy of punctures. To connect such a system with the laparoscopic ultrasound (LUS) transducer or the RFA needle especially designed adapters are needed. In this article we present our first experiences and prototypes for different sterilizable adapters for an electromagnetic navigation system for laparoscopic RFA.
All adapters were constructed with the help of a standard 3D CAD software. The adapters were built from medical stainless steel alloys and polyetherketone (PEEK). Prototypes were built in aluminium and polyoxymethilen (POM). We have designed and developed several adapters for the connection of electromagnetical tracking systems with different RFA needles and a laparoscopic ultrasound transducers.
Based on earlier experiences of the initial version of the adapter, sterilisable adapters have been developed using biocompatible materials only. After short introduction, the adapters could be mounted to the laparoscopic ultrasound probe and the RFA needle under sterile conditions without any difficulties. Laboratory tests showed no disturbance of laparoscopic navigation system by the adapters. Anatomic landmarks in the liver could be safely reached. The adapters showed good feasibility, ergonomics, sterilizability and stability.
The development of usable adapters is the prerequisite for accurate tracking of a RFA needle for laparoscopic navigation purposes as well as 3D navigated ultrasound data acquisition. We designed, tested and used different adapters for the use of a laparoscopic navigation system for the improvement of laparoscopic RFA.
PMCID: PMC2174491  PMID: 17974003
2.  Rapid intraoperative insulin assay: a novel method to differentiate insulinoma from nesidioblastosis in the pediatric patient 
Hyperinsulinism is the most common cause of recurrent and persistent hypoglycemia in infancy and childhood. Causes can include nesidioblastosis, pancreatic islet cell tumors such as insulinoma, and associations with multiple endocrine neoplasia syndromes. Although new, improved imaging techniques have allowed for more precise preoperative localization of insulinomas, the differentiation of nesidioblastosis and insulinoma, particularly in children, can be challenging. To improve intraoperative localization and confirmation of successful resection of insulinoma, a novel hormonal assay, the rapid intraoperative insulin assay, is reported for the first time in a pediatric patient. This intraoperative radioimmunoassay for insulin yields results within several minutes and confirms complete resection of insulinoma.
Case description
We present a case of pancreatic insulinoma in a child with symptoms of severe hypoglycemia, causing seizures. The insulinoma was enucleated laparoscopically, and rapid intra-operative insulin assay used to determine the success of the procedure.
Discussion and evaluation
This rapid intra-operative test provides a valuable adjunct for determining complete excision in complicated cases of recurrent or questionable insulinoma. Although not a common problem, for pediatric patients in whom the diagnosis is not clear, this test may provide a novel approach to confirming disease.
We propose the use of this assay in facilitating intra-operative resection and confirmation of complete excision in pediatric patients. This population may especially benefit from this novel assay to confirm complete resection and to differentiate multiple etiologies of hyperinsulinism.
PMCID: PMC2116998  PMID: 17958895
3.  Duke Surgery Patient Safety: an open-source application for anonymous reporting of adverse and near-miss surgical events 
Studies have shown that 4% of hospitalized patients suffer from an adverse event caused by the medical treatment administered. Some institutions have created systems to encourage medical workers to report these adverse events. However, these systems often prove to be inadequate and/or ineffective for reviewing the data collected and improving the outcomes in patient safety.
To describe the Web-application Duke Surgery Patient Safety, designed for the anonymous reporting of adverse and near-miss events as well as scheduled reporting to surgeons and hospital administration.
Software architecture
DSPS was developed primarily using Java language running on a Tomcat server and with MySQL database as its backend.
Formal and field usability tests were used to aid in development of DSPS. Extensive experience with DSPS at our institution indicate that DSPS is easy to learn and use, has good speed, provides needed functionality, and is well received by both adverse-event reporters and administrators.
This is the first description of an open-source application for reporting patient safety, which allows the distribution of the application to other institutions in addition for its ability to adapt to the needs of different departments. DSPS provides a mechanism for anonymous reporting of adverse events and helps to administer Patient Safety initiatives.
The modifiable framework of DSPS allows adherence to evolving national data standards. The open-source design of DSPS permits surgical departments with existing reporting mechanisms to integrate them with DSPS. The DSPS application is distributed under the GNU General Public License.
PMCID: PMC1867823  PMID: 17472749
4.  Dissection and hemostasis with hydroxilated polyvinyl acetal tampons in open thyroid surgery 
The essential objectives for thyroidectomy are: avoidance of injury to the recurrent laryngeal nerves, conservation of the parathyroid glands, an accurate haemostasis and an excellent cosmesis. In the last 10 years major improvements and new technologies have been proposed and applied in thyroid surgery; among these mini-invasive thyroidectomy, regional anaesthesia and intraoperative neuromonitoring, and new devices for achieving dissection and haemostasis. Minor bleeding from small vessels could be a major complication in thyroid surgery. The purpose of ligating vessels is to maintain the surgical site free from an excess of blood and reduce blood loss in the patient.
Materials and methods
Hydroxylated polyvinyl acetal tampons (HPA) are made by a synthetic, open cell foam structure able to absorb fluids up to 25 times the initial weight. We tested their efficacy for small bleeding control and tissue dissection during several thyroid procedures.
HPA tampons have been found extremely useful to absorb blood coming from minor and diffuse loss, helping to control bleeding by a combined action of fluid absorption and local compression. The porous design of the tampon allows the use of the suction device right through the tampon itself. Thanks to the initial mildly hard consistency, we also used HPA tampons as dissecting instruments.
In our experience the use of HPA tampons resulted extremely efficient for minor bleeding control, fluids removal and tissue dissection during thyroid surgery.
PMCID: PMC1839768  PMID: 17411448
6.  Non-invasive MR imaging of inflammation in a patient with both asymptomatic carotid atheroma and an abdominal aortic aneurysm: a case report 
Inflammation is a recognized risk factor for the vulnerable atherosclerotic plaque.
USPIO-enhanced MRI imaging is a promising non-invasive method to identify high-risk atheromatous plaque inflammation in vivo in humans, in which areas of focal signal loss on MR images have been shown to correspond to the location of activated macrophages, typically at the shoulder regions of the plaque. This is the first report in humans describing simultaneous USPIO uptake within atheroma in two different arterial territories and again emphasises that atherosclerosis is a truly systemic disease. With further work, USPIO-enhanced MR imaging may be useful in identifying inflamed vulnerable atheromatous plaques in vivo, so refining patient selection for intervention and allowing appropriate early aggressive pharmacotherapy to prevent plaque rupture.
PMCID: PMC1839766  PMID: 17411449
7.  The influence of psychological factors on the outcomes of laparoscopic Nissen fundoplication 
Psychological factors play a role in a variety of gastrointestinal illness, including gastroesophageal reflux disease (GERD). Their impact on the surgical outcomes of antireflux surgery is unknown.
This is a single institution prospective controlled trial, comparing patients undergoing a laparoscopic Nissen fundoplication for GERD (LNF Group, n = 17) to patients undergoing an elective laparoscopic cholecystectomy for biliary colic (Control Group, n = 10). All patients had a psychological assessment before surgery, at 3 months and 6 months after surgery (i.e. Symptom CheckList-90-R somatization subset (SCL-90-R), Depression Anxiety Stress Scales, Anxiety sensitivity index, Illness attitude scale and Beck Depression Inventory II). GERD symptoms were recorded in the LNF Group using a standardized questionnaire (score 0–60). Patients with post-operative GERD symptoms score above 12 at 6 months were evaluated specifically. Statistical analysis was performed using a Student T test, and statistical significance was set at 0.05.
There was no significant difference in preoperative and postoperative psychological assessment between the two groups. In the LNF Group, 7 patients had persisting GERD symptoms at 6 months (GERD score greater than 12). The preoperative SCL-90-R score was also significantly higher in this subgroup, when compared to the rest of the LNF Group (18.2 versus 8.3, p < 0.05) and to the Control Group (18.2 versus 7.9, p < 0.05). There was no significant difference for the other psychological tests.
The SCL-90-R Somatization Subset, reflecting the level of somatization in a patient, may be useful to predict poor outcomes after antireflux surgery. Cognisance of psychological disorders could improve the selection of an optimal treatment for GERD and help reduce the rate of ongoing symptoms after LNF.
PMCID: PMC1839765  PMID: 17411450

Results 1-7 (7)