scholarly journals Positioning accuracy assessment of minimally invasive percutaneous injection techniques for the treatment of temporomandibular disorders

2020 ◽  
pp. 20200313
Author(s):  
Antônio Luís Neto Custódio ◽  
Andrew Cameron ◽  
Mahmoud Bakr ◽  
Chris Little ◽  
Bruno Ramos Chrcanovic ◽  
...  

Objective: The aim of the present study was to evaluate the accuracy of an extraoral CBCT-planned 3D-printed surgical guide aimed to percutaneous injection of substances into the temporomandibular joint (TMJ) and the lateral pterygoid muscle (LPM). Methods: Nine human cadaver heads were used. Pre-planning CBCT and facial scans were obtained and three percutaneous injection sites were planned: one for the lower compartment of the TMJ and two for the LPM. A digital surgical guide was then designed with small titanium sleeves and printed by a 3D printer. After the injections, new CBCT scans with the needles in place were obtained in order to assess the accuracy of the procedure in relation to the virtual planning. Results: The mean values for angle deviation were very low (range 1.13o-4.08o), the same happening for the mean difference in the length reached (range 1.82–2.64 mm), as well as for the mean difference in the needle tip dislocation (range 0.94–2.03 mm). Conclusion: The guide seems to be a reliable tool for accurate percutaneous injection of drugs into the inferior compartment of the TMJ and the LPM. Further studies are necessary to test the efficacy and validate the method in an in vivo study.

Author(s):  
Priyanka Jain ◽  
Rakesh Jain

Background & Method: We conducted a double blinded study at Index Medical College Hospital & Research Centre, Indore. The sample size was determined to be minimum of 120 cases as based upon previous years admission due to acute bronchiolitis. Initially, 146 cases were included in the study out of which 23 cases dropped out of the study after giving consent by guardian for participation in the study as they left against medical advice from the hospital. Result: The mean difference of CSS between 0 minutes to 60 minutes of nebulisation between groups in all cases was 0.4 ± 0.6, between 60 minutes and 4 hours was 0.8 ± 0.6, between 4 to 8 hours was 0.7 ± 0.6, between 8-12 hours was 0.6 ± 0.4, between 12-24 hours was 1.6 ± 0.9 and between 24-48 hours was 1.9 ± 0.9.The mean values and resultant p-value of ANOVA of various nebulising agents used for improvement in CSS shows significant association between various nebulising agents used along with improvement in CSS at the end of assessment at 48 hours of treatment. Conclusion: This study was conducted to establish the efficacy of each nebulisation agent (i.e.  adrenaline, 3% hypertonic saline and normal saline) currently used and compare the outcomes as there is not enough evidence amongst Indian population on level of efficacy of each drug in causing improvement in symptoms and signs in various severities of bronchiolitis in early childhood. Comparison of significant improvement in mean difference in CSS at various intervals in all cases compared between groups by post hoc test revealed non-significant difference (p-value 0.700) between 3% hypertonic saline and normal saline. Keywords: nebulisation, adrenaline, bronchiolitis & clinical.


1976 ◽  
Vol 40 (4) ◽  
pp. 625-629 ◽  
Author(s):  
R. L. Coon ◽  
N. C. Lai ◽  
J. P. Kampine

A newly developed, dual-function pH and PCO2 sensor was evaluated in this study. The sensors were placed in the femoral arteries of dogs anesthetized with sodium pentobarbital. Comparisons were made between systemic arterial pH and PCO2 measured using the sensor and those measured from blood samples drawn at 15-min intervals over a 7-h period using a bench instrument. The mean pH of the bench instrument measurements was 7.43. The mean difference of the sensor measurements from the bench instrument measurements for 207 comparisons was 0.0003 pH +/- 0.061 SD. The mean PCO2 of the bench instrument measurements was 40 mmHg. The mean difference of the sensor measurements from those of the bench instrument for 212 comparisons was -1.43 mmHg +/- 5.17 SD. The sensors performed equally well in the presence of metabolic or respiratory acidosis and alkalosis. The dual-function sensors evaluated in this study are useful for trend monitoring of pH and PCO2 over at least a 7-h period without recalibration. With improvement in the consistency of sensor construction, these sensors will be reliable in vivo sensing devices for blood pH and PCO2 and thus valuable research and clinical instruments.


2019 ◽  
Vol 141 (9) ◽  
Author(s):  
Yaghoub Dabiri ◽  
Kevin L. Sack ◽  
Nuno Rebelo ◽  
Peter Wang ◽  
Yunjie Wang ◽  
...  

We sought to calibrate mechanical properties of left ventricle (LV) based on three-dimensional (3D) speckle tracking echocardiographic imaging data recorded from 16 segments defined by American Heart Association (AHA). The in vivo data were used to create finite element (FE) LV and biventricular (BV) models. The orientation of the fibers in the LV model was rule based, but diffusion tensor magnetic resonance imaging (MRI) data were used for the fiber directions in the BV model. A nonlinear fiber-reinforced constitutive equation was used to describe the passive behavior of the myocardium, whereas the active tension was described by a model based on tissue contraction (Tmax). isight was used for optimization, which used abaqus as the forward solver (Simulia, Providence, RI). The calibration of passive properties based on the end diastolic pressure volume relation (EDPVR) curve resulted in relatively good agreement (mean error = −0.04 ml). The difference between the experimental and computational strains decreased after segmental strain metrics, rather than global metrics, were used for calibration: for the LV model, the mean difference reduced from 0.129 to 0.046 (circumferential) and from 0.076 to 0.059 (longitudinal); for the BV model, the mean difference nearly did not change in the circumferential direction (0.061) but reduced in the longitudinal direction from 0.076 to 0.055. The calibration of mechanical properties for myocardium can be improved using segmental strain metrics. The importance of realistic fiber orientation and geometry for modeling of the LV was shown.


2009 ◽  
Vol 53 (7) ◽  
pp. 2857-2864 ◽  
Author(s):  
Zheng Ma ◽  
Jiping Wang ◽  
Roger L. Nation ◽  
Jian Li ◽  
John D. Turnidge ◽  
...  

ABSTRACT Nephrotoxicity is an important limitation to the clinical use of colistin against Pseudomonas aeruginosa and other gram-negative pathogens. Previous work reported net tubular reabsorption of colistin by the kidney in vivo, but there is no knowledge of its disposition within the kidney. This study investigated the renal disposition and potential transport mechanisms of colistin in the isolated perfused rat kidney (IPK) model by perfusing with colistin sulfate alone (2 μg/ml) or in the presence of potential inhibitors (tetraethylammonium [TEA], glycine-glycine [Gly-Gly], or hydrochloric acid [HCl]) at three different concentrations. When perfused alone, the renal clearances (CLR) for colistin A and B (the major components of colistin) in control kidneys were constant and low (mean values < 0.05 ml/min throughout the perfusion). The mean clearance ratios [CR, defined as CLR/(f u × GFR), where f u is the fraction of drug unbound in perfusate and GFR is the glomerular filtration rate] were significantly less than 1. It was concluded that there is net tubular reabsorption of colistin, and this exceeded the reabsorption of water. Less than 10% eliminated from perfusate was recovered in urine, suggesting considerable renal accumulation of colistin. The CR values for colistin were significantly increased when perfused with TEA (500 μM), Gly-Gly (833 μM), and HCl (2,500, 5,000, and 10,000 μM). It is proposed that renal reabsorption of colistin may involve organic cation transporters (inhibited by TEA) and peptide transporters (inhibited by Gly-Gly) and that the process is sensitive to the pH of urine.


2016 ◽  
Vol 57 (6) ◽  
pp. 662-667 ◽  
Author(s):  
Ming-Wei Huang ◽  
Jian-Guo Zhang ◽  
Lei Zheng ◽  
Shu-Ming Liu ◽  
Guang-Yan Yu

Abstract To transfer the preplan for the head and neck brachytherapy to the clinical implantation procedure, a preplan-based 3D-printed individual template for needle insertion guidance had previously been designed and used. The accuracy of needle insertion using this kind template was assessed in vivo. In the study, 25 patients with head and neck tumors were implanted with 125I radioactive seeds under the guidance of the 3D-printed individual template. Patients were divided into four groups based on the site of needle insertion: the parotid and masseter region group (nine patients); the maxillary and paranasal region group (eight patients); the submandibular and upper neck area group (five patients); and the retromandibular region group (six patients). The distance and angular deviations between the preplanned and placed needles were compared, and the complications and time required for needle insertion were assessed. The mean entrance point distance deviation for all 619 needles was 1.18 ± 0.81 mm, varying from 0.857 ± 0.545 to 1.930 ± 0.843 mm at different sites. The mean angular deviation was 2.08 ± 1.07 degrees, varying from 1.85 ± 0.93 to 2.73 ± 1.18 degrees at different sites. All needles were manually inserted to their preplanned positions in a single attempt, and the mean time to insert one needle was 7.5 s. No anatomical complications related to inaccurately placed implants were observed. Using the 3D-printed individual template for the implantation of 125I radioactive seeds in the head and neck region can accurately transfer a CT-based preplan to the brachytherapy needle insertion procedure. Moreover, the addition of individual template guidance can reduce the time required for implantation and minimize the damage to normal tissues.


1963 ◽  
Vol 18 (4) ◽  
pp. 815-817 ◽  
Author(s):  
Earl S. Barker ◽  
Archer P. Crosley ◽  
John K. Clark

Renal respiratory quotient (RQ) has been calculated from data collected in unanesthetized human subjects. In contrast to RQ recently reported on anesthetized dogs, these data do not indicate a mean value greater than 1. Under control conditions in 24 subjects, renal RQ calculated without special corrections averaged 0.88. Correcting for differences in blood flow between renal artery and vein due to urine formation the mean was 0.73, with 95% confidence limits 0.49–0.97. With alkaline urines an additional correction for urinary excretion of CO2 is advised. Excluding procedures known to alkalinize the urine, RQ values were similar in 46 observations after a variety of experimental procedures. Since both numerator and denominator of the ratio involve small differences between large values, small analytical errors can produce large changes indistinguishable from physiologic variation. Therefore mean values rather than individual observations are stressed. While such values in our data appear similar to RQ for other organs and the whole body, they do not preclude considerable anaerobic metabolism. Submitted on August 9, 1962


2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 9025-9025
Author(s):  
V. I. Avramis ◽  
E. H. Panosyan ◽  
I. A. Avramis ◽  
F. Dorey ◽  
P. Gaynon

9025 Background: ASNase is an important agent in the treatment of childhood acute lymphoblastic leukemia. Most other chemotherapeutic agents require entry into cells and some variety of activation. ASNase acts unmodulated and totally outside of cells, targeting extracellular ASN and glutamine. Several investigators have described a relationship between ASNase activity and ASN. In vivo, the equilibrium asparagine level depends on the input rate of ASN derived from the nutrients plus the de novo biosynthesis minus its deamination from the serum ASNase activity. Imax is a pharmacodynamic (PD) parameter developed in 1980’s representing the cumulative input of ASN from nutrients and de novo biosynthesis. Of note, glutamine is the amino group source for the synthesis of ASN from aspartate. In Enzyme-substrate relationships a sigmoid relationship exists that reaches a maximum product formation (Imax). We reported a link between Day 14 ASN depletion - not ASNase activity - and response for children with ALL in first marrow relapse (Jarrar et al, 2006). Methods: On CCG-1962, 117 children with standard risk ALL were randomly allocated to native or pegylated ASNase. Relevant PK-PD parameters have been reported (Avramis et al, Blood 2002). ASNase activity was not predictive of EFS. Induction (IND) Day 3 - 24 serum ASN levels were fitted into a PD model and the Imax values were evaluated for 112 patients. Results: The median Imax values were 1E-6 nmoles/ml/min in all 112 (range 2.0E-2 to 1.0E-7) and in the native or PEG-ASNase randomized patients. The mean values were 1.1E-3.1±3E-3 in 112 patients and 1.5E-3±4.0E-3 & 1.1E-3±3.0E-3 nmoles/ml/min in the native or PEG-ASNase randomized patients. We examined EFS by Imax values in lifetable analyses. High Imax values predicted statistically poorer outcome (p<0.00001) with various cut-off values (e.g., Imax ≥1x 10−3 or Imax ≥5 × 10−4 nmoles/ml/min. The effect was similar in the native and pegylated ASNase subsets. ASNase activity was not prognostic. Conclusions: Hence, ASN Imax in serum is a treatment-independent PD prognostic factor in a subset of children with standard risk ALL. Strategies to provide uniform therapeutic effect among patients with differing Imax are under consideration. No significant financial relationships to disclose.


2011 ◽  
Vol 62 (3) ◽  
pp. 183-189 ◽  
Author(s):  
Kristina A. Szabo ◽  
Colin E. Webber ◽  
Christopher Gordon ◽  
Jonathan D. Adachi ◽  
Richard Tozer ◽  
...  

Purpose The objectives of this study were to utilise the XCT-2000 pQCT scanner to determine the mean values and the reproducibility of in vivo total, trabecular, and cortical volumetric bone measurements at distal and diaphyseal sites of the radius and the tibia, as well as calf muscle and subcutaneous fat areas, in healthy pre- and postmenopausal women. Methods Twenty-nine women (14 premenopausal and 15 postmenopausal) were recruited to participate in this study. Distal and diaphyseal sites of the radius (at 4% and 20% of the length of the radius) and tibia (at 4%, 38%, and 66% of the length of the tibia) were examined. Results The root mean square coefficient of variation for measurements at the distal tibia gave the most favorable reproducibility values for total (1.5%) and trabecular (1.6%) density, whereas the diaphyseal tibia showed the most favorable reproducibility value for cortical density (0.3%). The root mean square coefficients of variation for measurements of muscle and fat cross-sectional areas at the calf were 0.6% and 0.7%, respectively. At the distal tibia, the mean values for total ( P < .05) and trabecular ( P < .01) density were significantly lower in postmenopausal women than in premenopausal women. Conclusions The data presented here indicate that XCT-2000 pQCT scans at the tibia provide highly reproducible measurements of total, cortical, and trabecular bone as well as muscle and fat cross-sectional areas. Furthermore, significant differences in volumetric bone measurements between healthy pre- and postmenopausal women were evident only at the distal tibia, suggesting that this site warrants further study.


1984 ◽  
Vol 105 (2) ◽  
pp. 194-199 ◽  
Author(s):  
Jean-Noel Hugues ◽  
Albert G. Burger ◽  
A. Eugene Pekary ◽  
Jerome M. Hershman

Abstract. Nutrition influences thyroid function at the level of TSH secretion, at the level of monodeiodination, and possibly elsewhere. In order to study the effect of starvation on TSH secretion, 8 healthy male volunteers fasted for 30 h and were then refed with 800 kcal. Refeeding was performed at 19.00 h and blood was sampled at 20 min intervals until midnight. Control experiments were performed in the same subjects both when they were normally fed and when the starvation period was prolonged a further 5 h until midnight. Starvation decreased serum TSH levels to below 1 mU/l, and without refeeding the nocturnal peak of the TSH nycthemeral rhythm was abolished. With refeeding serum TSH tended to increase towards midnight and was significantly higher than during starvation. However, the serum TSH levels remained significantly below those at the same time of the day in the absence of a preceding starvation period. Serum T3 levels were significantly lower than in the fed state. The mean values were 1.84 ± 0.03 vs 2.30 ± 0.06 nmol/l (120 ±2 vs 150 ± 4 ng/100 ml, mean ± sem P < 0.01). Refeeding did not result in a measurable change in serum T3 concentration (1.80 ± 0.05 nmol/l; 120 ± 3 ng/100 ml, mean ± sem, n.s.). The contrary was true for rT3 levels which increased in starvation and tended to fall with refeeding, but this decrease was not significant. As glucocorticoids have been implicated in the control of monodeiodination and TSH secretion, serum cortisol levels were also measured. They did not differ during the 3 experimental periods. The results show that short-term starvation and refeeding may be a valuable tool for studying in vivo control of TSH secretion. The results show that short-term starvation and refeeding may be a valuable tool for studying in vivo control of TSH secretion.


1996 ◽  
Vol 17 (8) ◽  
pp. 499-502 ◽  
Author(s):  
Irene McClay ◽  
James Bray

The purpose of this study was to propose a new measure of rearfoot structure to further enhance the understanding of the function of the foot. Landmarks visible on sagittal plane radiographs were used to represent the approximate direction of the subtalar joint axis in the sagittal plane based upon descriptions from the literature of its orientation. Four landmarks were chosen, resulting in four calculated angles. One hundred lateral view radiographs were analyzed. The mean values ranged from 28.7° to 47.7°. These values are within the ranges reported from both cadaver and in vivo studies. Tests of repeatability of the measures resulted in intraclass coefficient values between 0.94 and 0.98, suggesting good reliability. All four angles correlated highly among each other ( r = 0.88–0.97). Examination of the validity of any one of these measures is left to those who are able to accurately calculate the orientation of the subtalar joint axis.


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