A prospective study of 100 cases of sterile T-RING™ digital tourniquet application.

The ideal finger tourniquet must be easy to use and provide a completely bloodless field with control of the pressure exerted at the compression site. The primary objective of this study was to evaluate the effectiveness of the T-RING™ digital tourniquet in emergency hand surgery; the secondary objective was to define the optimal indications and possible contraindications. This prospective study, undertaken between May 4 and July 30, 2015, comprised the application of 100 finger tourniquets in the following indications: all single or multiple digital wounds, distal from the base of the proximal phalanx, irrespective of their nature and the suspected structural damage. Data were collected with a questionnaire at the end of each surgical use of the finger tourniquet. An overall grade out of 30 was obtained by combining these scores. The facility of opening the packing was rated on average at 4/4, the facility of applying the finger tourniquet was rated at 3.8/4, the quality of the exsanguination at the beginning and at the end of the procedure were rated at 3.4/4 and 3.1/4, respectively, the difficulty related to positioning of the finger tourniquet was rated at 2.7/3, the facility of removing the finger tourniquet was rated at 3.6/4, the risk of forgetting the finger tourniquet at the end of the procedure was rated to 2.8/3, the comparison with an arm tourniquet was rated at 1.9/4. The overall grade was 25.1/30 on average. In current practice, use of the T-Ring™ tourniquet did not cause any difficulty. The tourniquet was never forgotten and the risk of forgetting it was considered low by the surgeons. The exsanguination appeared satisfactory, with a reduction in its effectiveness over time. We identified specific situations where its use could be indispensable: contraindication to trunk or plexus regional anesthesia, or as a relay to a pneumatic arm tourniquet after more than 2hours.

Rhinorrhée cérébrospinale: difficultés thérapeutiques et facteurs d'échec

Introduction : La rhinorrhee cerebrospinale (rCS) resulte d'une breche osteomeningee faisant communiquer les cavites naso-sinusiennes avec les espaces sous-arachnoidiens. Sa gravite est liee au risque de complications infectieuses endocraniennes. Objectifs : discuter les modalites de prise en charge de la rCS et en analyser les facteurs d'echec. Patients et methode : Il s'agit d'une etude retrospective a propos de 15 patients presentant une rhinorrhee cerebrospinale en rapport avec une breche meningee traitee dans notre service. Resultats : L'age moyen de nos patients etait de 44;9 ans. Le motif de consultation etait une rhinorrhee claire intermittente. la notion de meningite etait rapportee dans 2cas. Un scanner du massif facial etait pratique dans tous les cas. Une cisterno IRM etait pratiquee dans 7 cas. La voie endoscopique etait adoptee dans14 cas et la voie combinee dans 1 cas. L'interposition de la greffe etait faite selon la procedure overlay dans tous les cas. Deux recidives ont ete notees et ont ete reprises chirurgicalement avec succes. Conclusion : La voie endonasale est une approche efficace et non invasive des breches osteomeningees. elle trouve son indication meme en cas d'echec de la voie transcranienne

A method to evaluate dose errors introduced by dose mapping processes for mass conserving deformations.

PURPOSE: To present a method to evaluate the dose mapping error introduced by the dose mapping process. In addition, apply the method to evaluate the dose mapping error introduced by the 4D dose calculation process implemented in a research version of commercial treatment planning system for a patient case. METHODS: The average dose accumulated in a finite volume should be unchanged when the dose delivered to one anatomic instance of that volume is mapped to a different anatomic instance-provided that the tissue deformation between the anatomic instances is mass conserving. The average dose to a finite volume on image S is defined as d(S)=e(s)/m(S), where e(S) is the energy deposited in the mass m(S) contained in the volume. Since mass and energy should be conserved, when d(S) is mapped to an image R(d(S→R)=d(R)), the mean dose mapping error is defined as Δd(m)=|d(R)-d(S)|=|e(R)/m(R)-e(S)/m(S)|, where the e(R) and e(S) are integral doses (energy deposited), and m(R) and m(S) are the masses within the region of interest (ROI) on image R and the corresponding ROI on image S, where R and S are the two anatomic instances from the same patient. Alternatively, application of simple differential propagation yields the differential dose mapping error, Δd(d)=|∂d∂e*Δe+∂d∂m*Δm|=|(e(S)-e(R))m(R)-(m(S)-m(R))m(R) (2)*e(R)|=α|d(R)-d(S)| with α=m(S)/m(R). A 4D treatment plan on a ten-phase 4D-CT lung patient is used to demonstrate the dose mapping error evaluations for a patient case, in which the accumulated dose, D(R)=∑(S=0) (9)d(S→R), and associated error values (ΔD(m) and ΔD(d)) are calculated for a uniformly spaced set of ROIs. RESULTS: For the single sample patient dose distribution, the average accumulated differential dose mapping error is 4.3%, the average absolute differential dose mapping error is 10.8%, and the average accumulated mean dose mapping error is 5.0%. Accumulated differential dose mapping errors within the gross tumor volume (GTV) and planning target volume (PTV) are lower, 0.73% and 2.33%, respectively. CONCLUSIONS: A method has been presented to evaluate the dose mapping error introduced by the dose mapping process. This method has been applied to evaluate the 4D dose calculation process implemented in a commercial treatment planning system. The method could potentially be developed as a fully-automatic QA method in image guided adaptive radiation therapy (IGART).

The antagonism activity of bacteria isolated from potato cultivated soil.

Soil-borne fungal and bacterial root pathogens can cause serious losses to agricultural crops. Resistant plant varieties are not available for several soil-borne pathogens and chemical control is often insufficiently effective in soil. The enhancement of disease suppressive properties of soils will limit disease development, thus, being of great importance for sustainable agriculture as well as organic farming systems. The aim of this research is to find and identify suppressive soils in the Sétif's areas (potato field located in different regions of Sétif); this allows the selection of the indigenous soil bacteria that are able to develop several mechanisms of action related to biocontrol of phytopathogenic fungi affecting potato crops. Among 50 bacterial strains only 14 showed a wide range of antifungal action against the tested phytopathogenic fungi. With a range of inhibition percent from 0 to 92.30% especially Fusarium oxysporum f. sp. albedinis with 92% inhibition.

SU-E-T-526: Evaluation of Dose Mapping Errors via Use of a Volume-Based Dose Mapping Method.

PURPOSE: To quantify dose mapping errors (DMEs) of a point-based dose mapping method for 4D lung treatment plans. METHODS: Point-based dose mapping methods utilize deformation vector fields (DVFS) to interpolate dose from a deformed image. Volume-based dose mapping methods consider the volume overlap between deformed and reference voxels; defining dose as the integral energy divided by the integral mass of the voxel, and conserving integral dose . DME is defined as the dose differences between volume-based and point-based mapped dose (DME=(DpointBased-DvolumeBased)/DRx). The DME for a 4D lung case is compared with a bitmap DME method, both using a Pinnacle research version 8.1y DVF. DME is computed for ten 4D lung cases (five 10 phases, five 3 phase) with Pinnacle research version 9.100 DVFs. Multi-phase accumulated 4D DMEs are also evaluated. RESULTS: For all cases, the largest DMEs are located in the dose/density gradient regions. With Pinnacle 8.1y DVF, mapping dose from phase 9 to phase 0, results in a DME=-0.2%±6.1% (range of -76%∼112%). The same case with Pinnacle 9.100 DVFs, DME=0.3%±4.8%(-41%∼32%). Locations of large DME are consistent with those from the bitmap method. For the ten 4D lung cases, accumulated mean DME are within ±0.07% (std. deviations: 1∼5%, range -102%∼64%). Maximum tumor DMEs are less than 30cGy (DRx=7200cGy) for all patients. CONCLUSIONS: Due to its inherent integral dose conservation, volume-based dose mapping methods can quantify errors in point-based dose mapping methods. While mean DME values are small for the cases tested, standard deviations near 5% indicate that a substantial number of voxels have ∼5% dose mapping errors, however these dose errors do not occur in the target structures. Work supported by NIH P01CA116602.

Coverage optimized planning: probabilistic treatment planning based on dose coverage histogram criteria.

This work (i) proposes a probabilistic treatment planning framework, termed coverage optimized planning (COP), based on dose coverage histogram (DCH) criteria; (ii) describes a concrete proof-of-concept implementation of COP within the PINNACLE treatment planning system; and (iii) for a set of 28 prostate anatomies, compares COP plans generated with this implementation to traditional PTV-based plans generated with planning criteria approximating those in the high dose arm of the Radiation Therapy Oncology Group 0126 protocol. Let Dv denote the dose delivered to fractional volume v of a structure. In conventional intensity modulated radiation therapy planning, Dv has a unique value derived from the static (planned) dose distribution. In the presence of geometric uncertainties (e.g., setup errors) Dv assumes a range of values. The DCH is the complementary cumulative distribution function of D(v+). DCHs are similar to dose volume histograms (DVHs). Whereas a DVH plots volume v versus dose D, a DCH plots coverage probability Q versus D. For a given patient, Q is the probability (i.e., percentage of geometric uncertainties) for which the realized value of Dv exceeds D. PTV-based treatment plans can be converted to COP plans by replacing DVH optimization criteria with corresponding DCH criteria. In this approach, PTVs and planning organ at risk volumes are discarded, and DCH criteria are instead applied directly to clinical target volumes (CTVs) or organs at risk (OARs). Plans are optimized using a similar strategy as for DVH criteria. The specific implementation is described. COP was found to produce better plans than standard PTV-based plans, in the following sense. While target OAR dose tradeoff curves were equivalent to those for PTV-based plans, COP plans were able to exploit slack in OAR doses, i.e., cases where OAR doses were below their optimization limits, to increase target coverage. Specifically, because COP plans were not constrained by a predefined PTV, they were able to provide wider dosimetric margins around the CTV, by pushing OAR doses up to, but not beyond, their optimization limits. COP plans demonstrated improved target coverage when averaged over all 28 prostate anatomies, indicating that the COP approach can provide benefits for many patients. However, the degree to which slack OAR doses can be exploited to increase target coverage will vary according to the individual patient anatomy. The proof-of-concept COP implementation investigated here utilized a probabilistic DCH criteria only for the CTV minimum dose criterion. All other optimization criteria were conventional DVH criteria. In a mature COP implementation, all optimization criteria will be DCH criteria, enabling direct planning control over probabilistic dose distributions. Further research is necessary to determine the benefits of COP planning, in terms of tumor control probability and/or normal tissue complication probabilities.