A locally destructive, completely asymptomatic, C1-root schwannoma with base of skull invasion : a case report

Patients with C1 nerve root schwannomas usually present with signs relating to nerve root compression. However, asymptomatic presentations have never been reported. A healthy, 37-year-old female was referred in view of a slow-growing lump in the left posterosuperior aspect of the neck. The lump was asymptomatic and neurological examination was normal. Magnetic resonance imaging revealed a left C1 nerve root tumour, extending around the C1 vertebra and compressing the thecal sac. The tumour had invaded the basiocciput and was impinging on the left cerebellar hemispheric dura. Stereotactic biopsies of the lesion showed a spindle-cell tumour exhibiting an immunoprofile consistent with a schwannoma. The lesion was surgically excised by blunt dissection using a posterior midline approach. The case report adds to the diverse modes of presentation of C1 nerve root schwannomas, in that such lesions must be included in the differential diagnosis of asymptomatic posterior neck lumps.peer-reviewe

Magnetic assessment and modelling of the Aramis undulator beamline

Within the SwissFEL project at the Paul Scherrer Institute (PSI), the hard X-ray line (Aramis) has been equipped with short-period in-vacuum undulators, known as the U15 series. The undulator design has been developed within the institute itself, while the prototyping and the series production have been implemented through a close collaboration with a Swiss industrial partner, Max Daetwyler AG, and several subcontractors. The magnetic measurement system has been built at PSI, together with all the data analysis tools. The Hall probe has been designed for PSI by the Swiss company SENIS. In this paper the general concepts of both the mechanical and the magnetic properties of the U15 series of undulators are presented. A description of the magnetic measurement equipment is given and the results of the magnetic measurement campaign are reported. Lastly, the data reduction methods and the associated models are presented and their actual implementation in the control system is detailed.peer-reviewe

The relevance of reducing Veress needle overshooting

Safe insertion of the Veress needle during laparoscopy relies on the surgeons’ technical skills in order to stop needle insertion just in time to prevent overshooting in the underlying organs. To reduce this risk, a wide variety of Veress needle systems were developed with safety mechanisms that limit the insertion speed, insertion depth or decouple the driving force generated by the surgeon’s hand on the needle. The aim of this study is to evaluate current surgeons’ perceptions related to the use of Veress needles and to investigate the relevance of preventing overshooting of Veress needles among members of the European Association of Endoscopic Surgery (EAES). An online survey was distributed by the EAES Executive Office to all active members. The survey consisted of demographic data and 14 questions regarding the use of the Veress needle, the training conducted prior to usage, and the need for any improvement. A total of 365 members residing in 58 different countries responded the survey. Of the responding surgeons, 36% prefer the open method for patients with normal body mass index (BMI), and 22% for patients with high BMI. Of the surgeons using Veress needle, 68% indicated that the reduction of overshoot is beneficial in normal BMI patients, whereas 78% indicated that this is beneficial in high BMI patients. On average, the members using the Veress needle had used it for 1448 (SD 3031) times and felt comfortable on using it after 22,9 (SD 78,9) times. The average years of experience was 17,6 (SD 11,1) and the surgeons think that a maximum overshoot of 9.4 (SD 5.5) mm is acceptable before they can safely use the Veress needle. This survey indicates that despite the risks, Veress needles are still being used by the majority of the laparoscopic surgeons who responded. In addition, the surgeons responded that they were interested in using a Veress needle with an extra safety mechanism if it limits the risk of overshooting into the underlying structures.peer-reviewe

A case report of HPV negative small cell neuroendocrine carcinoma and squamous cell carcinoma of the cervix : a rare but fatal mix

Malignant neoplasms that show divergent differentiation, like squamous cell carcinoma (SCC) and small cell neuroendocrine carcinoma (SNEC), occur very rarely in the cervix. Neuroendocrine tumors of the female genital tract tend to occur in combination with other types of tumors although they have been also described to occur as solitary neoplasms. Here, we present a case of a 51-year-old woman with a one-month history of vaginal bleeding and one week history of persistent lower abdominal pain. On vaginal examination a large irregular fixed cylindrical mass in mid-vagina, extending to the cervix, was felt. A computerized tomographic scan showed a uterine mass with retroperitoneal and pelvic lymphadenopathy together with multiple bilateral lung metastases. Cytological analysis via a cervical pap smear reported a high-grade intraepithelial lesion and atypical glandular cells of undetermined significance. Histological analysis of the cervical biopsies showed a necrotic biphasic neoplasm. The morphological and immunohistochemical findings were those of a poorly differentiated carcinoma with squamous and high grade neuroendocrine (small cell) differentiation. Polymerase chain reaction analysis for Human Papilloma Virus (HPV) performed on shavings from the paraffin-embedded tissue showed no evidence of HPV DNA. The patient was planned to receive primary chemotherapy but passed away within 3 weeks of her diagnosis. In conclusion, tumors showing SNEC differentiation, together with rare cases of primary cervical SNEC exhibit a different disease profile when compared with pure cervical SCC, in that the former are highly aggressive and has a greater propensity for nodal and distant organ metastasis. These tumors are associated with a poor prognosis.peer-reviewe

The effect of carbon dioxide insufflation during transoral endoscopic thyroidectomy via a vestibular approach on internal jugular vein pressure changes : is there a safer alternative?

Transoral endoscopic thyroidectomy via a vestibular approach (TOETVA) is a minimally invasive surgical approach to the thyroid gland which has been shown to be relatively safe but comes with a number of novel complications. Some studies show that a sudden increase in intra-jugular pressure leads to an increase in intra-ocular pressure. These changes are particularly important in glaucoma patients since small changes may have a damaging effect on their vision. Our group has suggested that using a device to modify the standard TOETVA into a gasless 1 might lead to less changes in intra-jugular pressure.peer-reviewe

A locally destructive, completely asymptomatic, C1-root schwannoma with base of skull invasion: a case report

Patients with C1 nerve root schwannomas usually present with signs relating to nerve root compression. However, asymptomatic presentations have never been reported. A healthy, 37-year-old female was referred in view of a slow-growing lump in the left posterosuperior aspect of the neck. The lump was asymptomatic and neurological examination was normal. Magnetic resonance imaging revealed a left C1 nerve root tumour, extending around the C1 vertebra and compressing the thecal sac. The tumour had invaded the basiocciput and was impinging on the left cerebellar hemispheric dura. Stereotactic biopsies of the lesion showed a spindle-cell tumour exhibiting an immunoprofile consistent with a schwannoma. The lesion was surgically excised by blunt dissection using a posterior midline approach. The case report adds to the diverse modes of presentation of C1 nerve root schwannomas, in that such lesions must be included in the differential diagnosis of asymptomatic posterior neck lumps.peer-reviewe

Spatial variability of herbicide mobilisation and transport at catchment scale: insights from a field experiment

During rain events, herbicides can be transported from their point of application to surface waters, where they may harm aquatic organisms. Since the spatial pattern of mobilisation and transport is heterogeneous, the contributions of different fields to the herbicide load in the stream may vary considerably within one catchment. Therefore, the prediction of contributing areas could help to target mitigation measures efficiently to those locations where they reduce herbicide pollution the most. Such spatial predictions require sufficient insight into the underlying transport processes. To improve the understanding of the process chain of herbicide mobilisation on the field and the subsequent transport through the catchment to the stream, we performed a controlled herbicide application on corn fields in a small agricultural catchment (ca. 1 km2) with intensive crop production in the Swiss Plateau. Water samples were collected at different locations in the catchment (overland flow, tile drains and open channel) for two months after application in 2009, with a high temporal resolution during rain events. We also analysed soil samples from the experimental fields and measured discharge, groundwater level, soil moisture and the occurrence of overland flow at several locations. Several rain events with varying intensities and magnitudes occurred during the study period. Overland flow and erosion were frequently observed in the entire catchment. Infiltration excess and saturation excess overland flow were both observed. However, the main herbicide loss event was dominated by infiltration excess. Despite the frequent and wide-spread occurrence of overland flow, most of this water did not reach the channel directly, but was retained in small depressions in the catchment. From there, it reached the stream via macropores and tile drains. Manholes of the drainage system and storm drains for road and farmyard runoff acted as additional shortcuts to the stream. Although fast flow processes such as overland and macropore flow reduce the influence of the herbicide's chemical properties on transport due to short travel times, sorption properties influenced the herbicide transfer from ponding overland flow to tile drains (macropore flow). However, no influence of sorption was observed during the mobilisation of the herbicides from soil to overland flow. These observations on the role of herbicide properties contradict previous findings to some degree. Furthermore, they demonstrate that valuable insight can be gained by making spatially detailed observations along the flow paths.ISSN:1027-5606ISSN:1607-793

Pre-clinical evaluation of the new veress needle+ mechanism on thiel-embalmed bodies: a controlled crossover study – Experimental

Background: Veress needles (VN) are commonly used in establishing pneumoperitoneum in laparoscopic surgery. Previously, a VN with a new safety mechanism ‘VeressPLUS’ needle (VN+) was developed to reduce the amount of overshoot.Methods: Eighteen participants (novices, intermediates, and experts) performed in total of 248 insertions in a systematic way on Thiel-embalmed bodies with wide and small bore versions of the conventional VN (VNc) and the VN+. Insertion depth was measured by recording the graduations on the needle under direct laparoscopic vision.Results: Participants graded the bodies and the procedures as lifelike. Overall, a significant reduction (P&lt;0.001) in average insertion depth was found for the VN+ compared to the VNc of 26.0 SD16 mm versus 46.2 SD15 mm. The insertion depth difference in the novice group was higher compared to the intermediates and experts (P&lt;0.001). The average insertion depth for both needle types was less (P&lt;0.001) for female participants compared to male.Conclusion: This study indicated that the VN+ significantly reduced the insertion depth in all tested conditions. Whether the difference between female and male performance can be linked to differences in muscle control or arm mass should be further investigated. Useful technical information was gathered from this study to further improve the VN+.<br/

HPV positivity varies with technique and primer set, in formalin-fixed paraffin-embedded benign and malignant breast tissue from Malta

The role of human papillomavirus in breast cancer pathogenesis is an area of considerable debate following differing results from all over the world. This study analyzed paraffin embedded tissue from 19 patients with benign or malignant breast disease. Standard PCR with GP5+/6+ and FAP primers, proved negative in all cases. However, qRT-PCR using the SF10 primer set detected HPV DNA in 2 out of these samples. Whilst our data does not support a major role for HPV in the pathogenesis of breast disease in Malta, it definitely does not exclude it totally. This study also clearly shows that the method of analysis is one of the variables resulting in the range of differing results witnessed worldwide in this area of study.peer-reviewe