Quantitative MR-Bildgebung zur Charakterisierung der Skelettmuskulatur

2020 ◽  
Vol 29 (02) ◽  
pp. 132-142
Author(s):  
Klaus Engelke ◽  
Oliver Chaudry ◽  
Armin Nagel
Keyword(s):  

ZusammenfassungDieser Beitrag gibt einen Überblick über Magnetresonanztomographie-basierte (MRT-basierte) Methoden zur Quantifizierung der Muskeldegeneration. Neben Muskelvolumen kann mit Dixon-Bildgebung insbesondere der prozentuale Fettgehalt bestimmt werden. Daneben gibt es Ansätze, frühe Anzeichen einer Degeneration über die Verteilung des Entzündungsgrades oder der Natriumkonzentration in der Muskulatur zu visualisieren und quantifizieren. Bis auf die Natrium-Bildgebung werden diese Methoden bei Muskelerkrankungen routinemäßig zur Diagnose und Verlaufskontrolle eingesetzt.Im Bereich der Osteologie und Gerontologie wird zwar die Bedeutung der Muskel-Knochen-Einheit unter anderem für Frakturprädiktion und Gebrechlichkeit im Alter immer wieder betont, Degeneration der Muskulatur wird aber im Wesentlichen über extrinsische Parameter wie Muskelkraft und -funktion erfasst. Häufig benutzte intrinsische Parameter wie DXA Lean Mass oder Muskelvolumen, bestimmt mit CT oder MRT, korrelieren nur mäßig mit extrinsischen Parametern. Eine genauere Charakterisierung von Muskelqualität sollte dieses Manko aber beseitigen. Mit CT und MRT stehen entsprechende Methoden zur Verfügung, die jetzt aber in Studien zur altersassoziierten Muskeldegeneration, in Interventionsstudien und in Studien zur Frakturrisikoprognostik auch eingesetzt werden müssen.

2019 ◽  
Author(s):  
Munier Nour ◽  
Chantelle Baril ◽  
Saija Kontulainen ◽  
Ayisha Kurji ◽  
Adam Baxter-Jones ◽  
...  

2016 ◽  
Author(s):  
Vladyslav Povoroznyuk ◽  
Nataliia Dzerovych ◽  
Roksolana Povorooznyuk

2017 ◽  
Vol 49 (5S) ◽  
pp. 264
Author(s):  
Mary T. Imboden ◽  
Ann M. Swartz ◽  
Matthew P. Harber ◽  
Leonard A. Kaminsky

Author(s):  
Beatrice Heim ◽  
Florian Krismer ◽  
Klaus Seppi

AbstractDifferential diagnosis of parkinsonian syndromes is considered one of the most challenging in neurology. Quantitative MR planimetric measurements were reported to discriminate between progressive supranuclear palsy (PSP) and non-PSP-parkinsonism. Several studies have used midbrain to pons ratio (M/P) and the Magnetic Resonance Parkinsonism Index (MRPI) in distinguishing PSP patients from those with Parkinson's disease. The current meta-analysis aimed to compare the performance of these measures in discriminating PSP from multiple system atrophy (MSA). A systematic MEDLINE review identified 59 out of 2984 studies allowing a calculation of sensitivity and specificity using the MRPI or M/P. Meta-analyses of results were carried out using random effects modelling. To assess study quality and risk of bias, the QUADAS-2 tool was used. Eight studies were suitable for analysis. The meta‐analysis showed a pooled sensitivity and specificity for the MRPI of PSP versus MSA of 79.2% (95% CI 72.7–84.4%) and 91.2% (95% CI 79.5–96.5%), and 84.1% (95% CI 77.2–89.2%) and 89.2% (95% CI 81.8–93.8%), respectively, for the M/P. The QUADAS-2 toolbox revealed a high risk of bias regarding the methodological quality of patient selection and index test, as all patients were seen in a specialized outpatient department without avoiding case control design and no predefined threshold was given regarding MRPI or M/P cut-offs. Planimetric brainstem measurements, in special the MRPI and M/P, yield high diagnostic accuracy for the discrimination of PSP from MSA. However, there is an urgent need for well-designed, prospective validation studies to ameliorate the concerns regarding the risk of bias.


Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 309
Author(s):  
Kun-Yun Yeh ◽  
Hang Huong Ling ◽  
Shu-Hang Ng ◽  
Cheng-Hsu Wang ◽  
Pei-Hung Chang ◽  
...  

Background: This study investigates whether the appendicular skeletal muscle index (ASMI) was an independent prognostic predictor for patients with locally advanced head and neck cancer (LAHNC) receiving concurrent chemoradiotherapy (CCRT) and whether there were any differences in lean mass loss in different body regions during CCRT. Methods: In this prospective study, we analyzed the clinicopathological variables and the total body composition data before and after treatment. The factors associated with the 2-year recurrence-free survival rate (RFSR) were analyzed via logistic regression analysis. Results: A total of 98 patients were eligible for analysis. The body weight, body mass index, and all parameters of body composition significantly decreased after CCRT. The pretreatment ASMI was the only independent prognostic factor for predicting the 2-year RFSR (hazard ratio, 0.235; 95% confidence interval, 0.062–0.885; p = 0.030). There was at least 5% reduction in total lean and fat mass (p < 0.001); however, the highest lean mass loss was observed in the arms (9.5%), followed by the legs (7.2%), hips (7.1%), waist (4.7%), and trunk (3.6%). Conclusions: The pretreatment ASMI was the only independent prognostic predictor for the 2-year RFSR of LAHNC patients undergoing CCRT. Asynchronous loss of lean mass may be observed in different body parts after CCRT.


Author(s):  
Gislaine Satyko Kogure ◽  
Victor Barbosa Ribeiro ◽  
Flávia Ganoa de Oliveira Gennaro ◽  
Rui Alberto Ferriani ◽  
Cristiana Libardi Miranda-Furtado ◽  
...  

Abstract Objective The present study aimed to investigate the physical performance of handgrip strength (HGS) in women with polycystic ovary syndrome (PCOS). Methods A case-control study that included 70 women with PCOS and 93 age-matched healthy women aged between 18 and 47 years with body mass index (BMI) between 18 Kg/m2–39.9 Kg/m2. The serum levels of total testosterone, androstenedione, insulin, estradiol, thyroid-stimulating hormone (TSH), prolactin, sex hormone-binding globulin (SHBG), and 17-hydroxyprogesterone (17-OHP) were measured. The free androgen index (FAI) and the homeostatic model assessment of insulin resistance (HOMA-IR) were calculated. The body composition regions of interest (ROIs) were assessed by dual-energy X-ray absorptiometry (DXA), and the handgrip strength (HGS) was evaluated for both the dominant and the non-dominant hands with a manual Sammons Preston (Bolingbrook, IL, US) bulb dynamometer. Results Women with PCOS had high serum levels of total testosterone (p < 0.01), androstenedione (p = 0.03), and insulin (p < 0.01), as well as high FAI (p < 0.01) and HOMA-IR (p = 0.01) scores. Compared with the non-PCOS group, the PCOS group had greater total lean mass in the dominant hand (p < 0.03) and greater HGS in both the dominant and the non-dominant hands (p < 0.01). The HGS was correlated with lean mass (p < 0.01). Conclusion Women with PCOS have greater HGS. This may be associated with age and BMI, and it may be related to lean mass. In addition, the dominance effect on muscle mass may influence the physical performance regarding HGS in women with PCOS.


2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
M Borges ◽  
M Lemos Pires ◽  
R Pinto ◽  
G De Sa ◽  
I Ricardo ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Exercise prescription is one of the main components of phase III Cardiac Rehabilitation (CR) programs due to its documented prognostic benefits. It has been well established that, when added to aerobic training, resistance training (RT) leads to greater improvements in peripheral muscle strength and muscle mass in patients with cardiovascular disease (CVD). With COVID-19, most centre-based CR programs had to be suspended and CR patients had to readjust their RT program to a home-based model where weight training was more difficult to perform. How COVID-19 Era impacted lean mass and muscle strength in trained CVD patients who were attending long-term CR programs has yet to be discussed. Purpose To assess upper and lower limb muscle strength and lean mass in CVD patients who had their centre-based CR program suspended due to COVID-19 and compare it with previous assessments. Methods 87 CVD patients (mean age 62.9 ± 9.1, 82.8% male), before COVID-19, were attending a phase III centre-based CR program 3x/week and were evaluated annually. After 7 months of suspension, 57.5% (n = 50) patients returned to the face-to-face CR program. Despite all constraints caused by COVID-19, body composition and muscle strength of 35 participants (mean age 64.7 ± 7.9, 88.6% male) were assessed. We compared this assessment with previous years and established three assessment time points: M1) one year before COVID-19 (2018); M2) last assessment before COVID-19 (2019); M3) the assessment 7 months after CR program suspension (last trimester of 2020). Upper limbs strength was measured using a JAMAR dynamometer, 30 second chair stand test (number of repetitions – reps) was used to measure lower limbs strength and dual energy x-ray absorptiometry was used to measure upper and lower limbs lean mass. Repeated measures ANOVA were used. Results Intention to treat analysis showed that upper and lower limbs lean mass did not change from M1 to M2 but decreased significantly from M2 to M3 (arms lean mass in M2: 5.68 ± 1.00kg vs M3: 5.52 ± 1.06kg, p = 0.004; legs lean mass in M2: 17.40 ± 2.46kg vs M3: 16.77 ± 2.61kg, p = 0.040). Lower limb strength also decreased significantly from M2 to M3 (M2: 23.31 ± 5.76 reps vs M3: 21.11 ± 5.31 reps, p = 0.014) after remaining stable in the year prior to COVID-19. Upper limb strength improved significantly from M1 to M2 (M1: 39.00 ± 8.64kg vs M2: 40.53 ± 8.77kg, p = 0.034) but did not change significantly from M2 to M3 (M2 vs M3: 41.29 ± 9.13kg, p = 0.517). Conclusion After CR centre-based suspension due to COVID-19, we observed a decrease in upper and lower limbs lean mass and lower limb strength in previously trained CVD patients. These results should emphasize the need to promote all efforts to maintain physical activity and RT through alternative effective home-based CR programs when face-to-face models are not available or possible to be implemented.


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