Performance of Homebalance Test in an Assessment of Standing Balance in Elderly Adults.

Balance control is a critical task of daily life, the ability to maintain upright posture becomes of particular concern during aging when the sensory and motor system becomes deteriorated. Falls contribute to the most deaths caused by injury within the aged population, and the mortality rate following a fall is drastically elevated. Longitudinal and reliable assessment of balance control abilities is a critical point in the prediction of increased risk of falling in an elderly population. The primary aim of the study was to evaluate the efficiency of the Homebalance test in the identification of persons being at higher risk of falling. 135 subjects (82 women and 53 men) with geriatric syndrome have been recruited and the Homebalance and the Tinetti Balance test were performed. Results of both tests strongly correlated proving the good performance of the Homebalance test. Standing balance declines with increasing body mass index in both genders. Analysis of fluctuations of the center of pressure (COP) revealed higher frequency and magnitude in mediolateral direction COP movements when compared women to men. A strong negative correlation has been found between Tinetti static balance score and the total length of the COP trajectory during the examination on Homebalance (r = -0.6, p<0.001). Although both methods revealed good performance in detecting balance impairment, Homebalance test possesses higher precision due to the continuous nature of COP-derived parameters. In conclusion, our data proved that the Homebalance test is capable to identify persons with impaired balance control and thus are at higher risk of falling.

Minimally invasive endoscopically assisted remodelation (MEAR) of sagittal craniosynostosis: an alternative technique to open and endoscopic procedures with cranial orthosis time span reduction.

INTRODUCTION: Sagittal craniosynostosis represents the most frequent simplex skull suture pathology. There are currently several operative approaches to this defect. Minimally invasive techniques are preferred for young infants. Since July 2017, we have employed endoscopically assisted craniectomies followed by cranial orthosis. Gradually, we have developed our modified technique, the minimally invasive endoscopically assisted remodelation (MEAR). SURGICAL TECHNIQUE: MEAR is a combination of principles gained from classical cranial vault remodeling techniques and minimal invasive approaches. The long and wider lateral osteoectomies performed in the parietal and occipital bones along with loosening of the periosteum and dura adhesions at the lambdoid sutures lead to early correction of parieto-occipital dimensions. RESULTS: Thirty-one consecutive patients with scaphocephaly underwent MEAR. The median preoperative cephalic index of 67 units (P25:63.3, P75:70) was improved to a median postoperative cephalic index of 77 units (P25:75, P75: 81). Sufficient correction was achieved in all patients. Cranial orthosis was needed for a median of 1.5 months (P25:1, P75:2). We had no major surgical complications in this pilot series. CONCLUSIONS: With MEAR, we have achieved good cosmetic results. Duration of cranial orthosis was significantly shortened compared to conventional endoscopic-assisted procedures.

Implanted vagus nerve stimulation in 126 patients: surgical technique and complications.

INTRODUCTION: Vagus nerve stimulation is a palliative treatment for patients with refractory epilepsy to reduce the frequency and intensity of seizures. A bipolar helical electrode is placed around the left vagus nerve at the cervical level and is connected to the pulse generator placed in a subcutaneous pocket, most commonly in the subclavian region. METHODS: Between March 1998 and October 2019, we performed 196 procedures related to the vagal nerve stimulation at the Neurosurgery Department in Motol University Hospital. Of these, 126 patients were vagal nerve stimulator implantation surgeries for intractable epilepsy. The cases included 69 female and 57 male patients with mean age at the time of the implantation surgery 22±12.4 years (range 2.158.4 years). RESULTS: Nine patients (7.1%) were afflicted by complications related to implantation. Surgical complications included postoperative infection in 1.6%, VNS-associated arrhythmias in 1.6%, jugular vein bleeding in 0.8% and vocal cord paresis in 2.4%. One patient with vocal cord palsy also suffered from severe dysphagia. One patient (0.8%) did not tolerate extra stimulation with magnet due to a prolonged spasm in his throat. The extra added benefit of vagus stimulation in one patient was a significant reduction of previously regular severe headaches. CONCLUSION: Vagus nerve stimulation is an appropriate treatment for patients with drug-resistant epilepsy who are not candidates for focal resective surgery. Implantation of the vagus nerve stimulator is a relatively safe operative procedure.

Torcular dural sinus malformations: a grading system proposal.

BACKGROUND: Torcular dural sinus malformations (tDSMs) are congenital complex vascular anomalies often referred as a single unit. Nevertheless, they possess distinct anatomical features, clinical diversity, and markedly different outcomes. OBJECTIVE: On the basis of our institutional experience and analysis of published data, we propose a grading system. METHODS: We have identified 44 papers to which we added our four institutional cases for a total of 126 patients. Eight predictor variables were studied. In order to assess their individual impact on mortality and possible correlations, a logistic regression model was constructed through a stepwise forward process. RESULTS: Overall mortality was 22.1%. Mortality was higher in tDSM patients diagnosed postnatally, 40.7% versus a 15.6% in prenatally found cases (p = 0.007). We divided the patients into four grades. Grade I comprised patients with no feeder evidence and possessed the best outcomes (mortality of 7.55%). Mortality rose for grades II and III defined respectively by scarce and multiple feeders. Brain damage was the defining feature of grade IV. A mortality of 75% could be observed within this grade. Grade IV was further divided into grades IVa (antenatal) and IVb (postnatal cases). Furthermore, our logistic regression model found that brain damage (OR 11.3, p < 0.001, 95% CI 2.97-42.91) and patent feeders (OR 4, p = 0.03, 95% CI 1.15-13.86) were major determinants of poor outcome (area under ROC curve of 81.44%). CONCLUSION: The grading system (tDSM-GS) streamlines classification into four different grades facilitating both diagnosis, clinical decision-making, and proper prognostication.

Torcular dural sinus malformations: a single-center case series and a review of literature.

INTRODUCTION: Torcular dural sinus malformations (tDSMs) are rare vascular pathologies with various anatomoclinical pictures and prognosis. We analyzed our case series and corroborated the complexity of this rare unit by a review of literature. CASE SERIES: From 2003 to 2018, we treated four tDSMs patients. The evolution of three postnatally diagnosed cases of similar angioarchitecture contrasted with a fourth antenatally diagnosed case with significant torcular thrombosis. All patients were examined by computed tomography, magnetic resonance imaging, CT angiography, and MRI angiography. Three patients underwent digital subtraction angiography with embolization of feeders. Unusual pathological images were depicted. CONCLUSIONS: Early diagnosis along with embolization of feeders and lake could improve the outcome for tDSM patients with dural arteriovenous shunts. Ventriculoperitoneal shunt implantation before endovascular treatment led to significant worsening of both clinical presentation and MRI picture. For patients who persist with hydrocephalus despite the endovascular approach, we suggest endoscopic third ventriculostomy as a first-line treatment option. Antenatally diagnosed patients with thrombosed lakes constitute a prognostically better group of patients. Spontaneous thrombosis and remodelation of the lake can, however, still leave neurological sequelae, as observed in our patient.

Pigment-protein complexes are organized into stable microdomains in cyanobacterial thylakoids.

Thylakoids are the place of the light-photosynthetic reactions. To gain maximal efficiency, these reactions are conditional to proper pigment-pigment and protein-protein interactions. In higher plants thylakoids, the interactions lead to a lateral asymmetry in localization of protein complexes (i.e. granal/stromal thylakoids) that have been defined as a domain-like structures characteristic by different biochemical composition and function (Albertsson P-Å. 2001,Trends Plant Science 6: 349-354). We explored this complex organization of thylakoid pigment-proteins at single cell level in the cyanobacterium Synechocystis sp. PCC 6803. Our 3D confocal images captured heterogeneous distribution of all main photosynthetic pigment-protein complexes (PPCs), Photosystem I (fluorescently tagged by YFP), Photosystem II and Phycobilisomes. The acquired images depicted cyanobacterial thylakoid membrane as a stable, mosaic-like structure formed by microdomains (MDs). These microcompartments are of sub-micrometer in sizes (~0.5-1.5 µm), typical by particular PPCs ratios and importantly without full segregation of observed complexes. The most prevailing MD is represented by MD with high Photosystem I content which allows also partial separation of Photosystems like in higher plants thylakoids. We assume that MDs stability (in minutes) provides optimal conditions for efficient excitation/electron transfer. The cyanobacterial MDs thus define thylakoid membrane organization as a system controlled by co-localization of three main PPCs leading to formation of thylakoid membrane mosaic. This organization might represent evolutional and functional precursor for the granal/stromal spatial heterogeneity in photosystems that is typical for higher plant thylakoids.

Sagittal craniosynostosis associated with midline cephalhematoma or vice versa, case report and a review of the literature.

INTRODUCTION: Sagittal craniosynostosis associated with midline cephalhematoma is a rare finding. Despite the controversy regarding its etiopathogenesis, this condition represents a clear indication for surgery. CASE REPORT: We present a case of a 10-week-old boy with an ossified midline vertex cephalhematoma and sagittal craniosynostosis. The child underwent a cephalhematoma excision and minimally invasive non-endoscopic narrow vertex craniectomy, with calvarial vault remodeling followed by 2 weeks use of a cranial orthosis. On 5-month follow-up, mesocephaly was achieved. CONCLUSION: Our case is well documented with native CT, 3D CT, intraoperative pictures, and 3D head scan imaging. We described our minimally invasive non-endoscopic technique that led to a rapid cranial vault remodeling with reduction of cranial orthosis need. A review of literature focused on surgical techniques is included.

Intraoperative Thermography of the Electrical Stimulation Mapping: A Safety Control Study.

A standard procedure for continuous intraoperative monitoring of the integrity of the corticospinal tracts by eliciting muscle responses is the electric stimulation mapping (ESM). However, standard ESM protocols are ineffective in 20% of young children. We have developed a novel, highly efficient paradigm consisting of short-time burst (30 ms) of high frequency (500 Hz) and high peak current (≤100 mA), which may cause local tissue overheating. The presented safety control study was therefore designed. The infrared thermography camera captured to-be-resected cortex of 13 patients in vivo during ESM. Thermograms were image processed to reveal discrete ESM thermal effect of currents from 10 to 100 mA. Peak 100 mA currents induced a maximal increase in temperature of 3.1 °C, 1.23±0.72 °C in average. The warming correlated with stimulating electrode resistance ( ). The measurement uncertainty was estimated ± 1.01 ºC for the most skeptical conditions. The histopathological evaluation of stimulated tissue (performed in all cases) did not show any destructive changes. Our study demonstrates the ability of the thermographic camera to measure the discrete thermal effect of the ESM. The results provide evidence for the safety of the proposed protocol for full range currents with minimal risk of brain tissue damage.

Electromagnetic navigation-guided neuroendoscopic transfrontal transaqueductal fenestration of expansive posterior fossa arachnoid cyst with simultaneous endoscopic third ventriculostomy in an infant.

INTRODUCTION: We present an infant with an expansive posterior fossa arachnoid cyst and severe clinical deterioration due to decompensated obstructive hydrocephalus. Given the dilated Sylvius aqueduct, we favoured the endoscopic transfrontal transaqueductal route to approach the cyst. CASE REPORT: A 12-month-old boy was acutely admitted for severe symptoms of intracranial hypertension. Imaging revealed spacious cystic formation in the posterior fossa with expansive behaviour towards the brain stem, fourth ventricle and cerebellum associated with obstructive triventricular hydrocephalus. The patient underwent electromagnetically navigated transfrontal transaqueductal cyst fenestration with simultaneous ETV from two precoronal trajectories with a rigid endoscope. CONCLUSION: A transaqueductal approach with a rigid endoscope is rarely published, and we were amazed by the impact on the child's clinical improvement after this minimally invasive endoscopic procedure. The case is well documented with imaging and perioperative neuroendoscopic views.

Electromagnetic navigation-guided neuroendoscopic removal of radiation-induced intraforniceal cavernoma as a late complication of medulloblastoma treatment.

INTRODUCTION: Medulloblastoma is the most frequent malignant brain tumour in children. Radiation-induced cavernous haemangiomas (RICHs) are a known late complication of radiation exposure, especially in young children. CASE REPORT: We present a patient who underwent subtotal resection of posterior fossa medulloblastoma with subsequent chemotherapy and radiotherapy at the age of 10 years. A new lesion in the region of the left foramen of Monro appeared 16 years later. Based on the imaging results, metastasis or radiation-induced cavernoma was considered. The lesion had the same appearance on imaging as a rarely published intraventricular cavernoma of the foramen of Monro. Unlike the cavernoma of the foramen of Monro, this lesion was subependymal and intraforniceal. Using electromagnetic navigation and neuroendoscopy, the lesion was completely removed. Histopathological examination revealed a cavernous haemangioma. CONCLUSION: This is a unique case of intraforniceal paraforaminal cavernoma that was successfully removed endoscopically using electromagnetic neuronavigation and without neurological sequelae.

[Parametric monitoring of the quality of total mesorectal excision and surgical treatment of rectal carcinoma results of a multicenter study]. / Parametrické sledování kvality totální mezorektální excize a chirurgické lécby karcinomu rekta výsledky multicentrické studie.

INTRODUCTION: Tumour size and the quality of its complete surgical removal are the main prognostic factors in rectal cancer treatment. The number of postoperative local recurrences depends on whether the mesorectum has been completely removed - total mesorectal excision (TME) - and whether tumour-free resection margins have been achieved. The surgery itself and its quality depend on the accuracy of preoperative diagnosis and detection of risk areas in the rectum and mesorectum, on the surgeons skills, and finally on pathological assessment evaluating whether complete tumour excision has been accomplished including circumferential margins of the tumour, and whether mesorectal excision is complete. The aim of our study was to implement and standardize a new method of evaluation of the quality of the surgical procedure - TME - in rectal cancer treatment using an assessment of its circumferential margins (CRO) and completeness of the excision. METHODS: The study consisted of two parts. The first, multi-centre retrospective phase with 288 patients analysed individual partial parameters of the diagnosis, operations and histological examinations of the rectal cancer. Critical points were identified and a unified follow-up protocol was prepared. In the second, prospective part of this study 600 patients were monitored parametrically focusing on the quality of the TME and its effect on the oncological treatment results. RESULTS: The proportion of patients with restaging following neoadjuvant therapy increased from 60.0% to 81.7% based on preoperative diagnosis. The number of specimens missing an assessment of the mesorectal excision quality decreased from 52.9% in the retrospective part of to the study to 22.8% in the prospective part. The proportion of actually complete TMEs rose from 22.6% to 26.0%, and that of nearly complete TMEs from 10.1% to 24.0%. CONCLUSION: The introduction of parametric monitoring into routine clinical practice improved the quality of pre-treatment and preoperative diagnosis, examination of the tissue specimen, and consequently improved quality of the surgical procedure was achieved. KEY WORDS: rectal cancer TME - parametric monitoring - quality control.

An olfactory groove schwannoma with a pseudocyst compressing the basal ganglia, internal capsule and optic tracts.

INTRODUCTION: Olfactory groove schwannomas (OGSs) are extremely rare tumours, particularly in the paediatric population. CASE REPORT: A 13-year-old girl presented with two epileptic seizures, papilloedema and incomplete binasal quadrantanopia. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated a large heterogeneously enhancing tumour of the anterior skull base with a prominent dorsal pseudocyst. Interestingly, the pseudocyst embraced the right ICA bifurcation and displaced the optic tracts, optic chiasm and optic nerves and the ipsilateral basal ganglia. The patient underwent surgery via the frontolateral approach, and the tumour was completely removed. The pseudocyst was opened, and its wall was partially resected. It subsequently resolved completely. Histopathological examination yielded the rare diagnosis of schwannoma of the anterior skull base. CONCLUSION: Although extremely rare, olfactory groove schwannomas can be seen in paediatric patients. Our patient is the youngest ever reported with this histopathological diagnosis along with the formation of a large pseudocyst.

[Embryonal Tumors with Multilayer Rosettes--Rare Central Nervous System Tumors in Infants]. / Embryonálne tumory s mnohovrstvovými rozetami--vzácne tumory centrálneho nervového systému v detskom veku.

INTRODUCTION: The most recent findings show a histopathological, genetic and clinical uniformity in cases of tumors called embryonal tumors with multilayer rosettes. This group is composed of medulloepithelioma, ependymoblastoma and embryonal tumor with abundant neuropil and true rosettes. Amplification of locus 19q13.42, which includes C19MC cluster containing genes for microRNA, and also LIN28A positivity are present in all three entities. Dysregulation of epigenetic modifiers is very important in pathogenesis of the disease. These tumors manifest in little children (median less than 3 years of age); overall survival is 5-10%. CASE REPORT: Almost three year-old boy diagnosed with brainstem tumor: meduloepithelioma, WHO grade IV confirmed by histological investigation. He presented with dysarthria, bulbar syndrome, central lesion of the facial nerve, quadriparesis with right-side dominancy. He received three induction cycles of chemotherapy from March to May 2014 (according to protocol COG ACNS0334). Only partial improvement of his clinical state was reached. Signs of an intracranial hypertension appeared resulting in VP shunt insertion; impairment of consciousness developed after the induction cycles and before any other treatment could be initiated. He underwent radiotherapy due to vital indication. After application of two fractions (boost in the center of the tumor), the patient became quickly comatose. Spinal cord metastasis was demarked by MRI scan (in the level of 3rd cervical vertebra). A bilateral infiltration in pulmonary parenchyma, according to a radiologist metastasis-wise, was detected by CT scan (histologisation of infiltration was not implemented). The patient died in August 2014--six months after manifestation of first symptoms. CONCLUSION: We reported our first documented case of a patient with tumor from embryonal tumors with multilayer rosettes group in Slovakia. Nowadays, there is no effective treatment of these tumors. Research of molecules targeting to epigenetic modifiers would be one of the possible promises for future therapy.

Immunoparesis in MGUS - Relationship of uninvolved immunoglobulin pair suppression and polyclonal immunoglobuline levels to MGUS risk categories.

Monoclonal gammopathy of undetermined significance (MGUS) is an asymptomatic, potentially malignant condition. It has been established that annually approximately 1-2% of MGUS cases transforms into one of the malignant forms of monoclonal gammopathies. Progression risk factors include the quantity and type of M-protein, and namely the ratio of free light immunoglobulin chains (FLC). These factors, enable purposeful stratification of MGUS individuals. Some authors consider suppression of polyclonal immunoglobulin levels to be another progression factor. The aim of the study was to compare polyclonal immunoglobulin (PIg) levels with uninvolved heavy/light chain pair (HLC) levels in order to verify the degree of immunoparesis depending on MGUS risk category (0-3). The analyzed set consisted of 159 serum samples from MGUS patients (102 IgG, 57 IgA), who were stratified into 4 risk groups (0 - low, 1 - low-intermediate, 2 - high-intermediate and 3 - high risk of transformation). The results of analysis showed that with increasing degree of MGUS increases risk of immune paresis defined by decreasing levels of polyclonal immunoglobulins, ie. IgA and IgM in the case of IgG MGUS, respectively, IgG and IgM in case of IgA MGUS. Significant differences were also found when analyzing the levels of uninvolved HLC pairs IgG kappa (resp. IgG lambda) in IgG lambda (IgG kappa) dominant secretion. In the case of MGUS with IgA isotype, the results were similar. Discovery of the connection between the degree of immunosuppression and the level of MGUS risk contributes to our understanding of the relationship between biology, development and potential malignant transformation of MGUS. It is apparent that uninvolved HLC pair assay enables more reliable identification of at-risk MGUS patients than a simple quantitative assay for polyclonal immunoglobulins alone.

Histomorphometric diagnostics of renal osteopathy in chronic dialysis patients at high risk of cardiovascular disease.

UNLABELLED: Chronic kidney disease-mineral and bone disorder (CKD-MBD) ranks among clinically and pathogenetically significant complications in patients with CKD. Numerous factors are involved in its development, and histomorphometric analysis of the bone tissue is still necessary for accurate diagnosis. METHODS: The open, pilot, prospective study aimed at performing a comprehensive histomorphometric bone analysis in 26 dialysis patients and assessing the relationships of different types of CKD-MBD to selected parameters of calcium and phosphate metabolism, densitometry, activity of parathyroid glands, presence of diabetes mellitus, and duration of dialysis treatment. RESULTS: Comparison of the histomorphometric characteristics demonstrated statistically significant correlations between the volume of bone trabeculae and s-procollagen 1 (.754) as well as s-calcitonin (.856). Similarly, there was a positive correlation between the size of tetracycline lines and volume of bone trabeculae (.705) and a strong negative correlation with the thickness of trabeculae (-.442). When assessing the serum levels of s-osteoprotegerin and serum RANKL, there was a correlation with osteoid thickness and bone trabeculae thickness. In case of s-osteoprotegerin, a statistical power was demonstrated in relation to osteoid thickness (.880); in case of s-RANKL, a statistical power was demonstrated in relation to the thickness of trabeculae (.830). When assessing the influence of dialysis duration, relationships to the volume of trabecular bone (.665) and volume of bone trabeculae (.949) were demonstrated. Finally, a relationship between s-1,25-hydroxyvitamin D and s-osteoprotegerin was observed (.739); also the relationships demonstrated were significantly lower volume of bone trabeculae in men (p = 0.067) and lower values of s-osteocalcin and s-procollagen 1 in diabetic patients (p = 0.014). CONCLUSION: The results provide new noninvasive possibilities of CKD-MBD detection that are based on selected serum parameters of bone metabolism. Presented are possibilities of noninvasive assessment of different types of CKD-MBD using serum osteomarkers in relation to comprehensive CKD-MBD histomorphometry.

[Intraoperative sentinel lymph node detection in colon cancer resection - preliminary results]. / Peroperacní detekce sentinelové uzliny pri resekci pro karcinom kolon - predbezné výsledky.

INTRODUCTION: The aim of this paper is to evaluate the results of intraoperative sentinel node detection in colon cancer patients and to compare the number of nodes retrieved per specimen in comparison with standard resection. METHODS: Patients undergoing elective colon cancer resection were included in the study. The specimen and the sentinel lymph node were sent for histopathological examination. A group of patients from 2011 who underwent elective resection served as the study control. RESULTS: The control group comprised 56 patients. The average node count was 12.73 (4-27). The study group included 102 patients; 29 patients had to be excluded because of protocol deviation. Out of the remaining 73 (46 male and 27 female) patients, 24 were N-positive and 2 of them were pN1c. In the remaining 22 patients, the sentinel node was positive in 8 cases, corresponding to a sensitivity of 36.36%. The average lymph node count was 15.97(3-30) after patent blue dye injection. CONCLUSION: Intraoperative sentinel lymph node detection is an easy and feasible method. Despite the low sensitivity, the main positive effect of the method is the increased lymph node count per resection specimen.

Recurrent varicose veins: causes and neovascularisation. A 17-year experience.

AIM: The aim of the paper was to determine the causes of varicose vein recurrence and, when neovascularisation is suspected, to confirm or exclude its presence and to establish its contribution to the recurrence of varicose veins. METHODS: A retrospective analysis of a set of 217 legs reoperated in our department over a period of 17 years with a two-year prospective histological and histochemical (nestin) analysis of resected veins. RESULTS: Reflux as a cause of varicose vein recurrence was identified in 93% of the limbs. It was most commonly found in the area of the saphenofemoral junction, followed by the area of the saphenopopliteal junction. Reflux in the perforating veins was almost invariably linked to that in the saphenofemoral junction or saphenopopliteal junction; an isolated damage to the perforating veins was only present in three limbs. Histological and histochemical analysis was performed for the samples of eleven veins in which neovascularisation was suspected based on preoperative duplex ultrasonography evaluation. Neovascularisation was confirmed in none of these veins and none of them was the cause of recurrence. CONCLUSION: The major cause of varicose vein recurrence is a reflux left unresolved during the primary surgery, particularly in the area of the saphenofemoral junction. A less common cause is progression of the disease and the occurrence of a new reflux. Neovascularisation is of no importance for the recurrence of varicose veins.

Structure-based constitutive model can accurately predict planar biaxial properties of aortic wall tissue.

Structure-based constitutive models might help in exploring mechanisms by which arterial wall histology is linked to wall mechanics. This study aims to validate a recently proposed structure-based constitutive model. Specifically, the model's ability to predict mechanical biaxial response of porcine aortic tissue with predefined collagen structure was tested. Histological slices from porcine thoracic aorta wall (n=9) were automatically processed to quantify the collagen fiber organization, and mechanical testing identified the non-linear properties of the wall samples (n=18) over a wide range of biaxial stretches. Histological and mechanical experimental data were used to identify the model parameters of a recently proposed multi-scale constitutive description for arterial layers. The model predictive capability was tested with respect to interpolation and extrapolation. Collagen in the media was predominantly aligned in circumferential direction (planar von Mises distribution with concentration parameter bM=1.03 ± 0.23), and its coherence decreased gradually from the luminal to the abluminal tissue layers (inner media, b=1.54 ± 0.40; outer media, b=0.72 ± 0.20). In contrast, the collagen in the adventitia was aligned almost isotropically (bA=0.27 ± 0.11), and no features, such as families of coherent fibers, were identified. The applied constitutive model captured the aorta biaxial properties accurately (coefficient of determination R(2)=0.95 ± 0.03) over the entire range of biaxial deformations and with physically meaningful model parameters. Good predictive properties, well outside the parameter identification space, were observed (R(2)=0.92 ± 0.04). Multi-scale constitutive models equipped with realistic micro-histological data can predict macroscopic non-linear aorta wall properties. Collagen largely defines already low strain properties of media, which explains the origin of wall anisotropy seen at this strain level. The structure and mechanical properties of adventitia are well designed to protect the media from axial and circumferential overloads.