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  • 简介:AbstractBackground and objective:The size of the cochlea varies a lot among the human population bringing the necessity for electrode arrays to be available in various lengths irrespective of the cochlear implant (CI) brand. This research software helps in the estimation of the patient’s cochlear duct length (CDL) which is then used for the simulation of the correct length electrode array matching the patient’s cochlear size and as well in getting the patient specific cochlear frequency map.Methods:Visual Studio Express 2012 for Windows Desktop is used in the architecture of this research software. The basal turn diameter of the cochlea ( "A" value) needs to be measured from the pre-operative computed tomography (CT) image of the patient’s temporal bone. This "A" will be taken as the input for the CDL equations proposed by Alexiades et al for estimating the CDL along the basilar membrane for various insertion depths. Greenwood’s equation is then used in combination with the CDL for the full length of the cochlea in getting the patient specific frequency map.Results:The research software with the help of the "A" value as input, with few button clicks, gives the patient specific CDL for various insertion depths and the Greenwood’s frequency map. The users have the choice to select any electrode array of their choice and place it under the frequency map to see how good it fits to that particular patient’s cochlea. Also, given the possibility to drag and move the electrode array picture to mimic the post-operative actual electrode insertion depth.Conclusions:This research software simplifies the overall process of CDL estimation and in getting the patient specific cochlear frequency map. The clinicians get the chance to simulate placing the various electrode array lengths in patient cochlea in identifying the best fit electrode. This could help in pushing the CI field into the concept of individualized CI electrode array solution that ultimately benefits the patients.

  • 标签: Cochlear duct length Greenwood frequency map Electrode array
  • 简介:Brief-pulsestimulationat50Hzhasbeenshowntoterminateafterdischargesobservedinepilepsypatients.However,theoptimalpulsestimulationparametersforterminatingcorticalelectricalstimulation-inducedafterdischargesremainunclear.Inthepresentstudy,weexaminedtheeffectsofdifferentbrief-pulsestimulationfrequencies(5,50and100Hz)oncorticalelectricalstimulation-inducedafterdischargesin10patientswithrefractoryepilepsy.Resultsdemonstratedthatbrief-pulsestimulationcouldterminatecorticalelectricalstimulation-inducedafterdischargesinrefractoryepilepsypatients.Inconclusion,(1)abrief-pulsestimulationwasmoreeffectivewhentheafterdischargedidnotextendtothesurroundingbrainarea.(2)Ahigherbrief-pulsestimulationfrequency(especially100Hz)wasmorelikelytoterminateanafterdischarge.(3)Alowcurrentintensityofbrief-pulsestimulationwasmorelikelytoterminateanafterdischarge.

  • 标签: 短脉冲 电刺激 高频率 诱导 皮质 电流强度
  • 简介:Areaswithhighfrequencyactivitywithintheatriumarethoughttobe'drivers'oftherhythminpatientswithatrialfibrillation(AF)andablationoftheseareasseemstobeaneffectivetherapyine-liminatingDFgradientandrestoringsinusrhythm.ClinicalgroupshaveappliedthetraditionalFFT-basedapproachtogeneratethethree-dimensionaldominantfrequency(3DDF)mapsduringelectro-physiology(EP)proceduresbutliteratureisrestrictedonusingalternativespectralestimationtech-niquesthatcanhaveabetterfrequencyresolutionthatFFT-basedspectralestimation.

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  • 简介:BackgroundTheearlyendothelialdysfunctionofcarotidarteryinpatientswithtype2diabetesmellitus(T2DM)hasbeenrecognized.However,thefeasibilityandsignificanceofcarotidarteryendothelialdysfunctiondetectedbyultrasoundradio-frequencytechnologyhasbeenseldomstudied.MethodsThe2Dultrasoundimagesofthebilateralcommoncarotidarteriesfrom112casesofT2DMpatientsand50casesofnormalsubjectsinourhospitalwerecollectedtomeasureintima-mediathicknessmeans(IMTm),end-systolicinnerdiameter(Ds),end-diastolicinnerdiameter(Dd),resistanceindex(RI),pulseindex(PI),andthesystole/diastoleratio(S/D).Wealsoobservedthevariationoftheintima-mediathickness(IMT)aswellastheelasticityindexesofthecommoncarotidartery,suchasthecompliancecoefficient(CC),elasticitycoefficient(β),pulsewavevelocity(PWV)andaugmentationindex(AIx)throughinstrumentswithbuilt-inultrasoundradio-frequencytechniques,includingquantitativeintima-mediathickness(QIMT)andquantitativeanalysisofarterialstiffness(QAS).Thedifferencesoftheabove-mentionedparametersbetweenthetwogroupswereanalyzed.ResultsTherewerenostatisticallysignificantdifferencesinIMTm,Ds,Dd,RI,PIandS/DraitoofthecommoncarotidarteriesbetweengroupT2DMandthenormalgroup(P>0.01).Theβ,PWVandAIxingroupT2DMwereremarkablyhigherthanthoseinthecontrolgroup,withCCvaluebeingsignificantlylowerthanthelater(P<0.01or0.05).ConclusionUltrasoundradio-frequencytechniqueoffersearlierandmoreeffectiveevaluationofcarotidarteryendothelialdysfunctioninT2DMpatientswhencomparedwithconventional2Dultrasound,establishingimagingfoundationfortheearlypreventionandtreatmentofcardio-cerebrovascularcomplicationsinT2DMpatients.

  • 标签: 2型糖尿病 超声图像 功能障碍 血管内皮 射频技术 早期预防
  • 简介:AbstractBackground:High-frequency irreversible electroporation (H-FIRE) is a novel, next-generation nanoknife technology with the advantage of relieving irreversible electroporation (IRE)-induced muscle contractions. However, the difference between IRE and H-FIRE with distinct ablation parameters was not clearly defined. This study aimed to compare the efficacy of the two treatments in vivo.Methods:Ten Bama miniature swine were divided into two group: five in the 1-day group and five in the 7-day group. The efficacy of IRE and H-FIRE ablation was compared by volume transfer constant (Krans), rate constant (Kep) and extravascular extracellular volume fraction (Ve) value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), size of the ablation zone, and histologic analysis. Each animal underwent the IRE and H-FIRE. Temperatures of the electrodes were measured during ablation. DCE-MRI images were obtained 1, 4, and 7 days after ablation in the 7-day group. All animals in the two groups were euthanized 1 day or 7 days after ablation, and subsequently, IRE and H-FIRE treated liver tissues were collected for histological examination. Student’s t test or Mann-Whitney U test was applied for comparing any two groups. One-way analysis of variance (ANOVA) test and Welch’s ANOVA test followed by Holm-Sidak’s multiple comparisons test, one-way ANOVA with repeated measures followed by Bonferroni test, or Kruskal-Wallis H test followed by Dunn’s multiple comparison test was used for multiple group comparisons and post hoc analyses. Pearson correlation coefficient test was conducted to analyze the relationship between two variables.Results:Higher Ve was seen in IRE zone than in H-FIRE zone (0.14 ± 0.02 vs. 0.08 ± 0.05, t= 2.408, P = 0.043) on day 4, but no significant difference was seen in Ktrans or Kep between IRE and H-FIRE zones at all time points (all P > 0.05). For IRE zone, the greatest Ktrans was seen on day 7, which was significantly higher than that on day 1 (P = 0.033). The ablation zone size of H-FIRE was significantly larger than IRE 1 day (4.74 ± 0.88 cm2vs. 3.20 ± 0.77 cm2, t = 3.241, P = 0.009) and 4 days (2.22 ± 0.83 cm2vs. 1.30 ± 0.50 cm2, t = 2.343, P = 0.041) after treatment. Apoptotic index (0.05 ± 0.02 vs. 0.73 ± 0.06 vs. 0.68 ± 0.07, F = 241.300, P < 0.001) and heat shock protein 70 (HSP70) (0.03 ± 0.01 vs. 0.46 ± 0.09 vs. and 0.42 ± 0.07, F= 64.490, P < 0.001) were significantly different between the untreated, IRE and H-FIRE zones, but no significant difference was seen in apoptotic index or HSP70 between IRE and H-FIRE zone (both P > 0.05). Electrode temperature variations were not significantly different between the two zones (18.00 ± 3.77°C vs. 16.20 ± 7.45°C, t = 0.682, P = 0.504). The Ktrans value (r = 0.940, P = 0.017) and the Kep value (r = 0.895, P = 0.040) of the H-FIRE zone were positively correlated with the number of hepatocytes in the ablation zone.Conclusions:H-FIRE showed a comparable ablation effect to IRE. DCE-MRI has the potential to monitor the changes of H-FIRE ablation zone.

  • 标签: Irreversible electroporation High-frequency irreversible electroporation Dynamic contrast enhanced-magnetic resonance imaging Thermal damage