Magnetic resonance imaging pattern variability in dysferlinopathy.

The widespread use of magnetic resonance imaging (MRI) in the diagnosis of myopathies has made it possible to clarify the typical MRI pattern of dysferlinopathy. However, sufficient attention has not been given to the variability of MRI patterns in dysferlinopathy. MATERIALS AND METHODS: Twenty-five patients with the clinical manifestations of dysferlinopathy were examined. For all patients, creatine phosphokinase levels were measured and molecular genetics were examined. In two patients, immunohistochemical examinations of muscle biopsies were performed. MRI scanning was included T2 multi-slice multi-echo, T1 weighted, T2 weighted and Short Tau Inversion Recovery T2 weighted sequences. Quantitative and semi-quantitative evaluations of fatty replacement and swelling of the muscles were undertaken. RESULTS: Variability in the MRI patterns was lowest in the pelvis and leg muscles and highest in the thigh muscles. Three main types of MRI patterns were distinguished: posterior-dominant (80%), anterior-dominant (16%), and diffuse (4%). Among patients with the anterior-dominant pattern, the collagen-like variant (4%), proximal variant (4%) and pseudo-myositis (8%) were separately distinguished. CONCLUSIONS: Awareness of atypical MRI patterns in dysferlinopathy is important for increasing the efficiency of routine diagnostics and optimizing the search for causative gene mutations.

Defining degree of aortic occlusion for partial-REBOA: A computed tomography study on large animals.

INTRODUCTION: Partial resuscitative endovascular balloon occlusion of the aorta (P-REBOA) is a modified REBOA technique designed to help ameliorate ischemia-reperfusion injury. The balloon is partially deflated, allowing a proportion of aortic flow distal to the balloon. The aim of this study is to use an ovine model of haemorrhagic shock to correlate the degree of occlusion to several hemodynamic indices. MATERIALS AND METHODS: Six sheep weighing 35-46 kg underwent a controlled venous haemorrhage inside a CT scanner until the systolic arterial pressure (AP) dropped to <90 mmHg. A balloon positioned in an aortic zone I was incrementally filled with 1 mL of saline, with serial measurement of the proximal (carotid artery) and distal (femoral artery) mean APs (MAP) and intra-balloon pressure (IBP), along with CT imaging, following each inflation, until full occlusion was achieved. RESULTS: A diameter of the aorta at zone I was 16.0 (15.7-17.2) mm, with a cross-sectional area of 212 (194-233) mm2. Median volume of saline injected into the balloon until total occlusion was 7.0 (6.3-8.5) mL. During gradual balloon inflation, proximal MAP increased and distal MAP decreased proportionate to the degree of occlusion, in a linear fashion (proximal: r2 = 0.85, p < 0.001; distal: r2 = 0.95, p < 0.001). The femoral/carotid (F/C) pressure gradient also demonstrated a linear trend (r2 = 0.90, p < 0.001). The relationship between percentage occlusion and IBP was sigmoid. MAP values became significantly different at 40-49% occlusion and more (p < 0.01). Furthermore, a drop in the distal pulse pressure from 7.0 (5.5-16.5) to 2.0 (1.5-5.0) mmHg was observed at 80% occlusion. All animals had femoral pulse pressure <5 mmHg at 80% of occlusion and more, which also coincided with the observed loss of pulsatility of the femoral wave-form. CONCLUSION: Serial CT angiography at an ovine model of haemorrhagic shock demonstrates a correlation between the femoral MAP, F/C pressure gradient and degree of zone I P-REBOA during the staged partial aortic occlusion. These parameters should be considered potential parameters to define the degree of P-REBOA during animal research and clinical practice.