scholarly journals Cochlear Size Assessment Predicts Scala Tympani Volume and Electrode Insertion Force- Implications in Robotic Assisted Cochlear Implant Surgery

2021 ◽  
Vol 8 ◽  
Author(s):  
Anandhan Dhanasingh ◽  
Chloe Swords ◽  
Manohar Bance ◽  
Vincent Van Rompaey ◽  
Paul Van de Heyning
Keyword(s):  
Cochlear Implant ◽  
B Value ◽  
Scala Tympani ◽  
Insertion Force ◽  
B Values ◽  
Robotic Assisted ◽  
A Value ◽  
Straight Portion ◽  
The Mean ◽  
Electrode Insertion

Objectives: The primary aim was to measure the volume of the scala tympani (ST) and the length of the straight portion of the cochlear basal turn from micro-computed tomography (μCT) images. The secondary aim was to estimate the electrode insertion force based on cochlear size and insertion speed. Both of these objectives have a direct clinical relevance in robotic assisted cochlear implant (CI) surgery.Methods: The ST was segmented in thirty μCT datasets to create a three-dimensional (3D) model and calculate the ST volume. The diameter (A-value), the width (B-value), and the straight portion of the cochlear basal turn (S-value) were measured from the oblique coronal plane. Electrode insertion force was measured in ST models of two different sizes, by inserting FLEX24 (24 mm) and FLEX28 (28 mm) electrode arrays at five different speeds (0.1, 0.5, 1, 2, and 4 mm/s).Results: The mean A-, B-, and S-values measured from the 30 μCT datasets were 9.0 ± 0.5, 6.7 ± 0.4, and 6.9 mm ± 0.5, respectively. The mean ST volume was 34.2 μl ± 7 (range 23–50 μl). The ST volume increased linearly with an increase in A- and B-values (Pearson's coefficient r = 0.55 and 0.56, respectively). The A-value exhibited linear positive correlation with the B-value and S-value (Pearson's coefficient r = 0.64 and r = 0.66, respectively). In the smaller of the two ST models, insertion forces were higher across the range of insertion speeds during both array insertions, when compared to the upscaled model. Before the maximum electrode insertion depths, a trend toward lower insertion force for lower insertion speed and vice-versa was observed.Conclusion: It is important to determine pre-operative cochlear size as this seems to have an effect upon electrode insertion forces. Higher insertion forces were seen in a smaller sized ST model across two electrode array lengths, as compared to an upscaled larger model. The ST volume, which cannot be visualized on clinical CT, correlates with clinical cochlear parameters. This enabled the creation of an equation capable of predicting ST volume utilizing A- and B-values, thus enabling pre-operative prediction of ST volume.

Optimal Path Planning for Robotic Insertion of Steerable Electrode Arrays in Cochlear Implant Surgery

2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Jian Zhang ◽  
J. Thomas Roland ◽  
Spiros Manolidis ◽  
Nabil Simaan
Keyword(s):  
Path Planning ◽  
Cochlear Implant ◽  
Optimal Path ◽  
Electrode Array ◽  
Scala Tympani ◽  
Electrode Arrays ◽  
Insertion Force ◽  
Optimal Path Planning ◽  
Cochlear Implant Surgery ◽  
Electrode Insertion

This paper presents an optimal path planning method of steerable electrode arrays for robot-assisted cochlear implant surgery. In this paper, the authors present a novel design of steerable electrode arrays that can actively bend at the tip. An embedded strand in the electrode array provides an active steering degrees-of-freedom (DoF). This paper addresses the calibration of the steerable electrode array and the optimal path planning for inserting it into planar and three-dimensional scala tympani models. The goal of the path planning is to minimize the intracochlear forces that the electrode array applies on the walls of the scala tympani during insertion. This problem is solved by designing insertion path planning algorithms that provide best fit between the shape of the electrode array and the curved scala tympani during insertion. Optimality measures that account for shape discrepancies between the steerable electrode array and the scala tympani are used to solve for the optimal path planning of the robot. Different arrangements of DoF and insertion speed force feedback (ISFF) are simulated and experimentally validated in this paper. A quality of insertion metric describing the gap between the steerable electrode array and the scala tympani model is presented and its correspondence to the insertion force is shown. The results of using 1DoF, 2DoF, and 4DoF electrode array insertion setups are compared. The 1DoF insertion setup uses nonsteerable electrode arrays. The 2DoF insertion setup uses single axis insertion with steerable electrode arrays. The 4DoF insertion setup allows full control of the insertion depth and the approach angle of the electrode with respect to the cochlea while using steerable electrode arrays. It is shown that using steerable electrode arrays significantly reduces the maximal insertion force (59.6% or more) and effectively prevents buckling of the electrode array. The 4DoF insertion setup further reduces the maximal electrode insertion forces. The results of using ISFF for steerable electrodes show a slight decrease in the insertion forces in contrast to a slight increase for nonsteerable electrodes. These results show that further research is required in order to determine the optimal ISFF control law and its effectiveness in reducing electrode insertion forces.

Cochlear Implant Revision: Effects of Reimplantation on the Cochlea

1989 ◽  
Vol 98 (10) ◽  
pp. 813-820 ◽  
Author(s):  
Robert K. Jackler ◽  
Patricia A. Leake ◽  
William S. McKerrow
Keyword(s):  
Adverse Effects ◽  
Cochlear Implant ◽  
Round Window ◽  
Neural Population ◽  
Scala Tympani ◽  
New Device ◽  
Adult Cats ◽  
Electrode Insertion ◽  
Window Area ◽  
Reimplantation Procedure

The removal of an indwelling cochlear implant electrode followed by reinsertion of a new device has been a maneuver of uncertain cosequences to the cochlea and its surviving neural population. The present study was conducted in an attempt to elucidate the factors at determine whether a reimplantation procedure will be successful. Cochlear implantation followed by explanation and subsequent implantation was performed in eight adult cats. Evaluation of cochlear histopathology suggested a significant increase in electrode insertion trauma when there was proliferation of granulation tissue in the round window area and scala tympani. In other cases, atraumatic insertion was achieved without apparent injury to the cochlea. The results of a survey of cochlear implant manufacturers and surgeons indicate that electrode replacement can usually be accomplished without adverse effects. Difficulties have been encountered, however, in moving implants with protuberant electrodes and when reimplantation was attempted on a delayed basis following explanation.

SOMATOMEDIN A AND B IN SERUM FROM NEONATES, THEIR MOTHERS AND CORD BLOOD

1977 ◽  
Vol 85 (3) ◽  
pp. 636-643 ◽  
Author(s):  
H. Svan ◽  
K. Hall ◽  
M. Ritzén ◽  
K. Takano ◽  
A. Skottner
Keyword(s):  
Birth Weight ◽  
Cord Blood ◽  
Pregnant Women ◽  
Reference Group ◽  
B Value ◽  
Mean Value ◽  
Radioreceptor Assay ◽  
B Values ◽  
Positive Correlation ◽  
The Mean

ABSTRACT Somatomedin A by radioreceptor assay and somatomedin B by radioimmunoassay were measured in serum from women immediately after parturition and from their newborns. The mean levels of somatomedin A in both mothers (0.54 U/ml) and infants (0.50 U/ml) were significantly decreased compared to a reference group consisting of 21 non-pregnant women (0.91 U/ml). There was no difference between the mothers and their children. The mean somatomedin B value in serum from the mothers (63.9 μg/ml) was above that found in non-pregnant women (19.2 μg/ml) and the mean value in cord blood and serum from the infants (7.1 μg/ml) was below it. A positive correlation was noted between somatomedin A and B in cord blood; r = 0.78. The combined somatomedin A and B values in cord blood were positively correlated to birth weight (r = 0.51, P < 0.05).

scholarly journals Frictional Behavior of Cochlear Electrode Array Is Dictated by Insertion Speed and Impacts Insertion Force

2021 ◽  
Vol 11 (11) ◽  
pp. 5162
Author(s):  
Dana Dohr ◽  
Nicklas Fiedler ◽  
Wolfram Schmidt ◽  
Niels Grabow ◽  
Robert Mlynski ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Cochlear Implant ◽  
Electrode Array ◽  
Mechanical Trauma ◽  
Electrode Arrays ◽  
Friction Behavior ◽  
Insertion Force ◽  
Friction Coefficients ◽  
Electrode Insertion ◽  
The Impact

Background: During cochlear implantation, the electrode array has significant friction with the sensitive endocochlear lining and causes mutual mechanical trauma while the array is being inserted. Both, the impact of insertion speed on electrode friction and the relationship of electrode insertion force and friction have not been adequately investigated to date. Methods: In this study, friction coefficients between a CI electrode array (31.5 mm) and a tissue simulating the endocochlear lining have been acquired, depending on different insertion speeds (0.1, 0.5, 1.0, 1.5, and 2.0 mm/s). Additionally, the electrode insertion forces during the placing into a scala tympani model were recorded and correlated with the friction coefficient. Results: It was shown that the friction coefficient reached the lowest value at an insertion speed of 0.1 mm/s (0.24 ± 0.13), a maximum occurred at 1.5 mm/s (0.59 ± 0.12), and dropped again at 2 mm/s (0.45 ± 0.11). Similar patterns were observed for the insertion forces. Consequently, a high correlation coefficient (0.9) was obtained between the insertion forces and friction coefficients. Conclusion: The present study reveals a non-linear increase in electrode array friction, when insertion speed raises and reports a high correlation between friction coefficient and electrode insertion force. This dependence is a relevant future parameter to evaluate and reduce cochlear implant insertion trauma. Significance statement: Here, we demonstrated a dependence between cochlear electrode insertion speed and its friction behavior and a high correlation to insertion force. Our study provides valuable information for the evaluation and prevention of cochlear implant insertion trauma and supports the optimization of cochlear electrode arrays regarding friction characteristics.

scholarly journals Effect of adding different types of flour on the quality of low fat beef sausage

2021 ◽  
Vol 50 (1) ◽  
pp. 1-11
Author(s):  
U Habiba ◽  
MM Hossain ◽  
M Habib ◽  
MA Hashem ◽  
MS Ali
Keyword(s):  
Crude Protein ◽  
Storage Time ◽  
Storage Period ◽  
Rice Flour ◽  
B Value ◽  
Corn Flour ◽  
B Values ◽  
Overall Acceptability ◽  
A Value ◽  
Different Types

The experiment was conducted to find out the effect of different types of flour on the sensory, physicochemical, biochemical and microbiological properties of beef sausages. For this purpose, sausages were prepared into four different groups. They were treated control; beef sausage without flour, beef with 10% rice flour, beef with 10% wheat flour and beef with 10% corn flour. All parameters were analyzed at 0, 15th and 30th days of storage time. The proximate compositions of different sausage batters are analyzed and highly significant differences were found in dry matter and crude protein (%) content and significant differences were found in cooking loss (%), pH (%) and EE (%) content. While analyzing the different types of sausages, highly significant differences were found in pH, DM (%), CP (%) and EE (%) content and significant differences in Ash (%) content. Crude protein (%) and DM (%) increased, while Ash (%) and EE (%) decreased with increase of storage time. Significantly higher DM (%) and CP (%) were found in beef sausage without any flour, no significant differences were found among the flour groups in DM (%) and CP (%) content. The storage period had significant effect on different biochemical (FFA, POV and TBARS value) and microbial (TVC, TCC and TYMC) test. In all cases the values were increased with increase of storage time. The surface color (CIE L*, a*, b*) of sausages of different treatments at different storage period were measured.  No significant differences in L* value were found among beef sausages and storage time. On the other hand, different types of sausages had a significant effect on a* and b* values. Significantly higher a* value was found in beef sausage with 10% corn flour and b* value in beef sausage without any flour (Control). Storage period had no effect on b* values, but effect on a* values. Significantly lower a* value was found at 0 day of storage time. In sensory analysis, highly significant differences were found in flavor, off-flavor, juiciness, tenderness and overall acceptability among four types of sausages but no significant found in color. All the parameters were significantly lower in control sausage except off-flavour, which was significantly higher in control sausage. No significant differences were found in sensory parameters among the sausages manufactured from different types of flour. From this experiment, it might be concluded that addition of different types of flour increases the overall acceptability of beef sausage. Bang. J. Anim. Sci. 2021. 50 (1):1-11

Determination of Peanut Maturity Using a Hunter Colorimeter

1998 ◽  
Vol 25 (2) ◽  
pp. 99-103 ◽  
Author(s):  
C. C. Grimm ◽  
E. T. Champagne ◽  
T. H. Sanders
Keyword(s):  
Inverse Relationship ◽  
B Value ◽  
Physiological Maturity ◽  
B Values ◽  
A Value ◽  
Yellow Orange ◽  
L Value ◽  
Peanut Hull ◽  
Standard Deviations

Abstract Peanut maturity has previously been correlated with the color of the mesocarp of the peanut hull going from light to dark as the peanut matures. In this study, peanuts were sorted into maturity classes of yellow, orange A, orange B, brown and black based on the hull scrape method of Williams and Drexler. The Hunter L*, a*, and b* values were also measured on the dry pods for each class. The color of the mesocarp of freshly harvested peanuts was determined using a Hunter colorimeter. Hunter L*, a*, and b* values on individual peanuts, representative of each class using wet and dry hulls, were reproducibly determined with standard deviations of less than 0.8%. Yellow peanut pods had a median L* value of 70.0, while mature black peanut pods had a median L* value of 51.7 and median values for orange A, orange B and brown pods were, 68.0, 63.7, 57.0, respectively. A similar inverse relationship was observed for the b* value and maturity, while the a* value reached a maximum at orange A. No correlation was observed between the peanut maturity and L*, a*, and b* values acquired with the exocarp intact. Hunter L* and b* values of mesocarps show potential for determining physiological maturity of peanuts.

scholarly journals Evaluation of Color, Texture, Sensory and Antioxidant Properties of Gels Composed of Freeze-Dried Maqui Berries and Agave Sugar

Processes ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1294
Author(s):  
Patryk Sobaszek ◽  
Renata Różyło ◽  
Laura Dziki ◽  
Urszula Gawlik-Dziki ◽  
Beata Biernacka ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Phenolic Content ◽  
Antioxidant Properties ◽  
B Value ◽  
B Values ◽  
A Value ◽  
Freeze Dried ◽  
L Value ◽  
Aristotelia Chilensis ◽  
Powdered Form

The study aimed to determine the textural, sensory, and antioxidant properties of gels composed of maqui (Aristotelia chilensis) berries. These freeze-dried berries were tested in a powdered form as an additive (0–5%) to agave sugar (20%) gels. Freeze-dried maqui powdered berries were dark purple to almost black in color and were characterized by an L* value of 16.3, an a* value of 8.3, and a b* value of −9.6. The b* values decreased from 11.8 to 2.3 with the increase in the amount of berry powder. There were no significant changes in the color of gels composed of berries at 4% and 5% concentration. Gels lost (almost twice) their hardness as the amount of maqui increased. The lowest values of hardness and the highest values of elasticity, springiness, gumminess, and chewiness were observed at 4% concentration of dried berries. The type of sugar did not affect the lightness of the gels (L* parameter) and the a* value. The assessors evaluated the gels composed of agave sugar (20%) and 4% maqui and 0.5% citric acid to be the best. Phenolic content and antioxidant activity were significantly higher in these gels compared to the control gels. After obtaining this low sugar gels, consumers could enrich their diets with healthier products.

Seismotectonic maps of the European area

1975 ◽  
Vol 65 (6) ◽  
pp. 1721-1732
Author(s):  
K. L. Kaila ◽  
N. Madhava Rao
Keyword(s):  
B Value ◽  
Regression Curve ◽  
B Values ◽  
Regression Curves ◽  
European Area ◽  
A Value ◽  
The Alps ◽  
Seismotectonic Map ◽  
Good Agreement ◽  
Regional Tectonics

abstract Seismicity maps based on A value, b value, and return period for earthquakes with magnitude 6 and above have been prepared for the European area using the Kaila and Narain (1971) method. For the preparation of these maps, a modified relation A = 6.36b − 1.00 has been used instead of the earlier relation where A and b are constants in the cumulative regression curve represented by log N = A − bM. The A-value seismicity map also shows regional tectonics superimposed on it, thus yielding the seismotectonic map of Europe. These seismicity maps reveal that the European area consists of seven main high seismic activity zones named as the Balkan high, the Aegean high, the Apennine-sicilian high, the Alps high, the Carpathian high, the Saharan-Pyrenees high and the Iceland-Arctic high which are described in detail with their relationship to regional tectonics. The b values determined by the new method and shown on the b-value seismicity map are compared with those determined by other workers using earthquake regression curves for various regions of Europe and they show a very good agreement with each other.

scholarly journals Determination of temporal value of a-value and b-value to identify the level brittle of rock and seismic activity in the Palu region

2019 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Afryanti Veronika Simangunsong ◽  
Ramadhan Priadi ◽  
Anak Agung Istri Dwilyantari ◽  
Agus Marsono
Keyword(s):  
Maximum Likelihood ◽  
Seismic Activity ◽  
B Value ◽  
B Values ◽  
A Value ◽  
Calculation Results ◽  
Resistance To Stress ◽  
Index Value ◽  
Earthquake Data

<span lang="EN-US">The Palu area is a region that has a high seismic potential as a result of the existence of the Palu Koro Fault. The Koro Palu Fault is an active sinistral fault that moves with velocity around 25-30 mm/year. This research purpose to determine the a-value and b-value temporally for identify rock brittle levels and seismicity levels in the Palu area using the Maximum Likelihood Guttenberg-Richter method. The data used in this study are earthquake data from the BMKG and USGS catalogs for 2008-2018 over a period of 10 years located at 0840 LU 40 2.620LS and 118,590 BT - 121.70 BT. Based on the results of data processing, there were 3033 earthquake distributions in the earthquake over a 10-year period. The calculation results show variations in the value of b-values in the range 0.55-0.961 and the a-value in the range 3.63-5.42. The highest b-value was obtained in 2015 at 0.961 as an indication of increased seismic activity in the Palu area. After the Palu M 7.4 earthquake on 28 September  2018, there was a significant decrease in the value of the b-value to 0.685. Based on the trend of b-value values which continued to decline from 2015 until 2018, it was identified in the rock's resistance to stress is high in the Palu area. Whereas for the seismicity index value of the Palu area of 0.040789 with the earthquake return period 7 is 25 years. </span>

Sign in / Sign up

Export Citation Format

Share Document