Evaluation of Diffusional Characteristics and Microstructure in Unilateral Vocal Fold Paralysis Using Diffusion Tensor Imaging

Objective: To investigate the value of diffusion tensor imaging (DTI) in the evaluation of vocal fold tissue microstructure after recurrent laryngeal nerve (RLN) injury. Methods: Six canines were divided into 2 groups: a unilateral vocal fold paralysis group (n = 4) and a control group (n = 2). The RLN was cut in the unilateral vocal fold paralysis group, and no intervention was applied in the control group. After 4 months, the canines’ larynges were removed and placed in a small animal magnetic resonance imaging (MRI) system (9.4T BioSpec MRI; Bruker, Germany). After scanning, the vocal folds were isolated, sectioned, and stained. The slides were then analyzed for the cross-sectional area and muscle fiber density through feature extraction technology. Pearson correlation analysis was performed on the DTI scan and histological section extraction results. Results: In the vocal fold muscle layer, the fractional anisotropy (FA) of the unilateral RLN injury group was higher than that of the control group, and the Tensor Trace was lower than that of the control group. This difference was statistically significant, P < .05. In the lamina propria, the FA of the unilateral RLN injury group was lower than that of the control group, P > .05, and the Tensor Trace was lower than that of the control group, P < .05. The muscle fiber cross-sectional area of the RLN injury group was significantly smaller than the control group with statistical significance, P < .05, and the density of muscle fibers was lower, P < .05. The correlation coefficient between FA and the cross-sectional area was −0.838, P = .002, and .726; P = .017 between Tensor Trace and the cross-sectional area. Conclusion: Diffusion tensor imaging is an effective method to assess the changes in the microstructure of atrophic vocal fold muscle tissue after RLN injury.

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Atrophy patterns in isolated subscapularis lesions

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04241-5 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Gernot Seppel ◽

Andreas Voss ◽

Daniel J. H. Henderson ◽

Simone Waldt ◽

Bernhard Haller ◽

...

Keyword(s):

Muscle Atrophy ◽

Area Ratio ◽

Cross Sectional Area ◽

Control Group ◽

Sectional Area ◽

Cross Sectional ◽

Subscapularis Muscle ◽

Mri Scans ◽

The Mean ◽

The Cross

Abstract Background While supraspinatus atrophy can be described according to the system of Zanetti or Thomazeau there is still a lack of characterization of isolated subscapularis muscle atrophy. The aim of this study was to describe patterns of muscle atrophy following repair of isolated subscapularis (SSC) tendon. Methods Forty-nine control shoulder MRI scans, without rotator cuff pathology, atrophy or fatty infiltration, were prospectively evaluated and subscapularis diameters as well as cross sectional areas (complete and upper half) were assessed in a standardized oblique sagittal plane. Calculation of the ratio between the upper half of the cross sectional area (CSA) and the total CSA was performed. Eleven MRI scans of patients with subscapularis atrophy following isolated subscapularis tendon tears were analysed and cross sectional area ratio (upper half /total) determined. To guarantee reliable measurement of the CSA and its ratio, bony landmarks were also defined. All parameters were statistically compared for inter-rater reliability, reproducibility and capacity to quantify subscapularis atrophy. Results The mean age in the control group was 49.7 years (± 15.0). The mean cross sectional area (CSA) was 2367.0 mm2 (± 741.4) for the complete subscapularis muscle and 1048.2 mm2 (± 313.3) for the upper half, giving a mean ratio of 0.446 (± 0.046). In the subscapularis repair group the mean age was 56.7 years (± 9.3). With a mean cross sectional area of 1554.7 mm2 (± 419.9) for the complete and of 422.9 mm2 (± 173.6) for the upper half of the subscapularis muscle, giving a mean CSA ratio of 0.269 (± 0.065) which was seen to be significantly lower than that of the control group (p < 0.05). Conclusion Analysis of typical atrophy patterns of the subscapularis muscle demonstrates that the CSA ratio represents a reliable and reproducible assessment tool in quantifying subscapularis atrophy. We propose the classification of subscapularis atrophy as Stage I (mild atrophy) in case of reduction of the cross sectional area ratio < 0.4, Stage II (moderate atrophy) in case of < 0.35 and Stage III (severe atrophy) if < 0.3.

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Role of diffusion tensor imaging in the evaluation of ulnar nerve involvement in leprosy

British Journal of Radiology ◽

10.1259/bjr.20210290 ◽

2021 ◽

pp. 20210290

Author(s):

Ankita Aggarwal ◽

Chandan Jyoti Das ◽

Neena Khanna ◽

Raju Sharma ◽

Deep Narayan Srivastava ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

Peripheral Neuropathy ◽

Ulnar Nerve ◽

Diffusion Tensor ◽

Cross Sectional Area ◽

Ulnar Neuropathy ◽

Control Group ◽

Sectional Area ◽

Cross Sectional

Objective: Early detection of peripheral neuropathy is extremely important as leprosy is one of the treatable causes of peripheral neuropathy. The study was undertaken to assess the role of diffusion tensor imaging (DTI) in ulnar neuropathy in leprosy patients. Methods: This was a case–control study including 38 patients (72 nerves) and 5 controls (10 nerves) done between January 2017 and June 2019. Skin biopsy proven cases of leprosy, having symptoms of ulnar neuropathy (proven on nerve conduction study) were included. MRI was performed on a 3 T MR system. Mean cross-sectional area, fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of ulnar nerve at cubital tunnel were calculated. Additional ancillary findings and appearance of base sequences were evaluated. Results: Ulnar nerve showed thickening with altered T2W signal in all the affected nerves, having an average cross-sectional area of 0.26 cm2. Low FA with mean of 0.397 ± 0.19 and high ADC with mean of 1.28 ± 0.427 x 10 −3 mm2/s of ulnar nerve in retrocondylar groove was obtained. In the control group, mean cross-sectional area was 0.71cm2 with mean FA and ADC of 0.53 ± 0.088 and 1.03 ± 0.24 x 10 −3 mm2/s respectively. Statistically no significant difference was seen in diseased and control group. Cut-off to detect neuropathy for FA and ADC is 0.4835 and 1.1020 × 10 −3 mm2/s respectively. Conclusion: DTI though is challenging in peripheral nerves, however, is proving to be a powerful complementary tool for assessment of peripheral neuropathy. Our study validates its utility in infective neuropathies. Advances in knowledge: 1. DTI is a potential complementary tool for detection of peripheral neuropathies and can be incorporated in standard MR neurography protocol. 2. In leprosy-related ulnar neuropathy, altered signal intensity with thickening or abscess of the nerve is appreciated along with locoregional nodes and secondary denervation changes along with reduction of FA and rise in ADC value. 3. Best cut-offs obtained in our study for FA and ADC are 0.4835 and 1.1020 × 10 −3 mm2/s respectively.

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Effects of weight loss in ewes in early pregnancy on muscles and meat quality of lambs

The Journal of Agricultural Science ◽

10.1017/s0021859698006133 ◽

1999 ◽

Vol 132 (1) ◽

pp. 103-116 ◽

Cited By ~ 14

Author(s):

D. I. KRAUSGRILL ◽

N. M. TULLOH ◽

W. R. SHORTHOSE ◽

K. SHARPE

Keyword(s):

Body Weight ◽

Meat Quality ◽

Early Pregnancy ◽

Cross Sectional Area ◽

Control Group ◽

Sectional Area ◽

Muscle Weight ◽

Cross Sectional ◽

Crown Rump Length ◽

The Cross

Three successive experiments, of similar design, were carried out during 1986–88 at Mount Derrimut, Australia. Mature Merino ewes were mated to Poll Dorset rams and then allocated to either a control group (C) or a treatment group (R). Ewes from each treatment were slaughtered 60, 70, 100 or 140 days post-conception and the development of their foetuses was compared in terms of body size and muscle characteristics. In Expts 1 and 2, some ewes were allowed to lamb and the progeny in each group were slaughtered after reaching a body weight of 35 kg, for comparison of growth rates, muscle characteristics and meat quality.In each experiment, treatment extended from mating to day 70 of pregnancy and, during this period, both groups were housed. Ewes in group C were kept as one group and fed ad libitum and ewes in group R were individually penned and fed a restricted ration of the same diet as that given to group C in order to achieve a steady loss of body weight. In Expt 1, this loss was 8 kg but, in Expts 2 and 3, feed intake was controlled according to condition score and, during this period, group R ewes lost 25–35% of their body weight at mating. After day 70, all ewes were kept grazing and were offered supplementary feed at rates sufficient for a steady increase in ewe body weights.Foetuses in group R were lower in body weight (P<0·05), crown-rump length (P<0·05) and girth (P<0·01). However, birth weights and mean ages of the 35 kg lambs at slaughter did not differ significantly between treatments.There were no significant differences between treatments for the semitendinosus (ST) and semimembranosus (SM) muscles in total muscle weight, DNA content, protein content, nor in the ratios of muscle weight[ratio ]DNA and protein[ratio ]DNA. However, there were significant differences between experiments, which indicated that cell size in the ST and SM muscles was lower in Expt 2 than in Expt 1.In day 70 foetuses, the cross-sectional area of α fibres was greater (P<0·05) in group R than in group C but by day 140 the difference was no longer significant. At day 70, there was also a positive correlation (r=0·65, P<0·01) between the cross-sectional area of β fibres and the number of α fibres surrounding each of them. There were no significant differences between treatments at any age in the percentages of βR, αR and αW fibres.Meat from group R lambs was more tender than that from group C lambs as indicated by significantly lower means in the SM muscle for adhesion (P<0·01) and Warner–Bratzler Peak Force (WB PF) measurements (P<0·05).Although some effects of nutritional restriction were found, severe feed shortage in early pregnancy in sheep is unlikely to have significant effects on the production of prime lamb meat provided that adequate nutrition is available during late pregnancy and post-natal growth.

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Efficacy of Shear Wave Elasticity for Evaluating Myocardial Hypertrophy in Hypertensive Rats

10.21203/rs.3.rs-668697/v1 ◽

2021 ◽

Author(s):

Yoichi Takaya ◽

Kazufumi Nakamura ◽

Rie Nakayama ◽

Ohtsuka Hiroaki ◽

Naofumi Amioka ◽

...

Keyword(s):

Shear Wave ◽

Myocardial Hypertrophy ◽

Interventricular Septum ◽

Left Ventricular ◽

Cross Sectional Area ◽

Control Group ◽

Sectional Area ◽

Hypertensive Rats ◽

Cross Sectional ◽

The Cross

Abstract Shear wave (SW) imaging is a novel ultrasound-based technique for assessing tissue characteristics. SW elasticity may be useful to assess the severity of hypertensive left ventricular (LV) hypertrophy. This study aimed to evaluate the efficacy of SW elasticity for assessing the degree of myocardial hypertrophy using hypertensive rats. Rats were divided into hypertension group and control group. SW elasticity was measured on the excised heart. Myocardial hypertrophy was assessed histologically. LV weight was greater in hypertension group. An increase in interventricular septum and LV free wall thicknesses was observed in hypertension group. SW elasticity was significantly higher in hypertension group than in control group (14.6 ± 4.3 kPa vs. 6.5 ± 1.1 kPa, P < 0.01). The cross-sectional area of cardiomyocytes was larger in hypertension group than in control group (397 ± 50 µm2 vs. 243 ± 14 µm2, P < 0.01), and SW elasticity was positively correlated with the cross-sectional area of cardiomyocytes (R = 0.96, P < 0.01). This study showed that SW elasticity was higher in hypertensive rats and was closely correlated with the degree of myocardial hypertrophy, suggesting the efficacy of SW elasticity for estimating the severity of hypertensive LV hypertrophy.

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The Quantitative Assessment of Respiratory Muscles by Computed Tomography in Patients of Amyotrophic Lateral Sclerosis

10.21203/rs.3.rs-167015/v1 ◽

2021 ◽

Author(s):

Di Wu ◽

Yujia Cao ◽

Yan Cui ◽

Baoyu Yuan ◽

Yijing Guo ◽

...

Keyword(s):

Computed Tomography ◽

Amyotrophic Lateral Sclerosis ◽

Respiratory Muscles ◽

Cross Sectional Area ◽

Diaphragm Muscle ◽

Control Group ◽

Sectional Area ◽

Cross Sectional ◽

The Cross ◽

Lateral Sclerosis

Abstract Objectives Progressive weakness of respiratory muscle is common to patients with amyotrophic lateral sclerosis, which leads to respiratory failure, even death. The evaluation of respiratory muscle is essential to evaluate the severity during the progression of the disease and choose appropriate interventions. This study aimed to evaluate the respiratory muscles change of the patients with amyotrophic lateral sclerosis by regular chest computed tomography. Methods The cross-sectional area of respiratory muscles in amyotrophic lateral sclerosis patients was retrospectively reviewed. The severity of the disease was determined by the value of the amyotrophic lateral sclerosis function score scale. A healthy control group was selected with well-matched to the amyotrophic lateral sclerosis patients. Results Compared with the healthy control group, the cross-sectional area of the diaphragm muscle was lower in amyotrophic lateral sclerosis patients. The reduced cross-sectional area of respiratory muscles has a positive correlation with a lower amyotrophic lateral sclerosis function score. Patients with amyotrophic lateral sclerosis further showed a significant reduction in the cross-sectional area of respiratory muscles after 6-8 months.Conclusions The single-slice axial computed tomography is a fast and reliable method to quantitatively assess the cross-sectional area of respiratory muscles, especially diaphragm muscle, in disease progression.

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Efficacy of shear wave elasticity for evaluating myocardial hypertrophy in hypertensive rats

Scientific Reports ◽

10.1038/s41598-021-02271-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yoichi Takaya ◽

Kazufumi Nakamura ◽

Rie Nakayama ◽

Hiroaki Ohtsuka ◽

Naofumi Amioka ◽

...

Keyword(s):

Shear Wave ◽

Myocardial Hypertrophy ◽

Interventricular Septum ◽

Left Ventricular ◽

Cross Sectional Area ◽

Control Group ◽

Sectional Area ◽

Hypertensive Rats ◽

Cross Sectional ◽

The Cross

AbstractShear wave (SW) imaging is a novel ultrasound-based technique for assessing tissue characteristics. SW elasticity may be useful to assess the severity of hypertensive left ventricular (LV) hypertrophy. This study aimed to evaluate the efficacy of SW elasticity for assessing the degree of myocardial hypertrophy using hypertensive rats. Rats were divided into hypertension group and control group. SW elasticity was measured on the excised heart. Myocardial hypertrophy was assessed histologically. LV weight was greater in hypertension group. An increase in interventricular septum and LV free wall thicknesses was observed in hypertension group. SW elasticity was significantly higher in hypertension group than in control group (14.6 ± 4.3 kPa vs. 6.5 ± 1.1 kPa, P < 0.01). The cross-sectional area of cardiomyocytes was larger in hypertension group than in control group (397 ± 50 μm2 vs. 243 ± 14 μm2, P < 0.01), and SW elasticity was positively correlated with the cross-sectional area of cardiomyocytes (R = 0.96, P < 0.01). This study showed that SW elasticity was higher in hypertensive rats and was closely correlated with the degree of myocardial hypertrophy, suggesting the efficacy of SW elasticity for estimating the severity of hypertensive LV hypertrophy.

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The area of eye muscle of beef cattle carcasses

Australian Journal of Experimental Agriculture ◽

10.1071/ea9630249 ◽

1963 ◽

Vol 3 (10) ◽

pp. 249

Author(s):

RM Seebeck

Keyword(s):

Beef Cattle ◽

Cross Sectional Area ◽

Carcass Weight ◽

Sectional Area ◽

Muscle Area ◽

Cross Sectional ◽

Eye Muscle ◽

Angus Cattle ◽

The Cross

Variations in the cross-sectional area of eye muscle of carcasses cut between the tenth and eleventh ribs were investigated, using 105 Hereford and 51 Angus steers aged 20 months. These cattle consisted of three groups, born in successive years. At constant carcass weight, statistically significant differences in eye muscle area were found between breeds and between years. Breed and year differences were also found in eye muscle area with width and depth of eye muscle constant, so that there are limitations to the estimation of eye muscle area from width and depth measurements. A nomograph is given for estimating eye muscle area from width and depth for Hereford and Angus cattle, when all animals are reared in the same year and environment. The use of eye muscle area as an indicator of weight of carcass muscle is discussed.

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Comparison of the Cross Sectional Area, the Loss in Volume and the Mechanical Properties of LAE442 and MgCa0.8 as Resorbable Magnesium Alloy Implants after 12 Months Implantation Duration

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.675 ◽

2010 ◽

Vol 638-642 ◽

pp. 675-680 ◽

Cited By ~ 6

Author(s):

Martina Thomann ◽

Nina von der Höh ◽

Dirk Bormann ◽

Dina Rittershaus ◽

C. Krause ◽

...

Keyword(s):

Mechanical Properties ◽

Cross Sections ◽

Degradation Process ◽

Cross Sectional Area ◽

Bending Test ◽

Sectional Area ◽

Cross Sectional ◽

Initial Strength ◽

Three Point Bending ◽

The Cross

Current research focuses on magnesium based alloys in the course of searching a resorbable osteosynthetic material which provides sufficient mechanical properties besides a good biocompatibility. Previous studies reported on a favorable biocompatibility of the alloys LAE442 and MgCa0.8. The present study compared the degradation process of cylindrical LAE442 and MgCa0.8 implants after 12 months implantation duration. Therefore, 10 extruded implants (2.5 x 25 mm, cross sectional area 4.9 mm²) of both alloys were implanted into the medullary cavity of both tibiae of rabbits for 12 months. After euthanization, the right bone-implant-compound was scanned in a µ-computed tomograph (µCT80, ScancoMedical) and nine uniformly distributed cross-sections of each implant were used to determine the residual implants´ cross sectional area (Software AxioVisionRelease 4.5, Zeiss). Left implants were taken out of the bone carefully. After weighing, a three-point bending test was carried out. LAE442 implants degraded obviously slower and more homogeneously than MgCa0.8. The mean residual cross sectional area of LAE442 implants was 4.7 ± 0.07 mm². MgCa0.8 showed an area of only 2.18 ± 1.03 mm². In contrast, the loss in volume of LAE442 pins was more obvious. They lost 64 % of their initial weight. The volume of MgCa0.8 reduced clearly to 54.4 % which corresponds to the cross sectional area results. Three point bending tests revealed that LAE442 showed a loss in strength of 71.2 % while MgCa0.8 lost 85.6 % of its initial strength. All results indicated that LAE442 implants degraded slowly, probably due to the formation of a very obvious degradation layer. Degradation of MgCa0.8 implants was far advanced.

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