In this paper, we present a method for micro-endoscopic topography measurement utilizing two-wavelength holography. Initially, we evaluate the inter-core dispersion and cross-talk of two commercially available imaging fiber bundles (CFBs) and introduce the concept of virtual surface roughness as a limiting factor of achievable measurement resolution. Subsequently, we describe a micro-endoscope setup incorporating 3D-printed micro-optics, resulting in a total diameter of less than 450 µm.
View Article and Find Full Text PDFAging is characterized by a number of hallmarks including loss of mitochondrial homeostasis and decay in stress tolerance, among others. Unicellular eukaryotes have been widely used to study chronological aging. As a general trait, calorie restriction and activation of mitochondrial respiration has been proposed to contribute to an elongated lifespan.
View Article and Find Full Text PDFIn this paper, we demonstrate digital holographic imaging through a 27-m-long fog tube filled with ultrasonically generated fog. Its high sensitivity makes holography a powerful technology for imaging through scattering media. With our large-scale experiments, we investigate the potential of holographic imaging for road traffic applications, where autonomous driving vehicles require reliable environmental perception in all weather conditions.
View Article and Find Full Text PDFIn general, matrices for tissue engineering must maintain structural integrity during the process of tissue formation and promote vascularization of developing tissue. Therefore, collagen sponges, manufactured by an approach that offers the potential of unidirectional pore size, were seeded with human umbilical vein endothelial cells (HUVEC) to demonstrate a positive effect on cell proliferation. In addition, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) have been used to promote proliferation of HUVEC on optimized collagen sponges.
View Article and Find Full Text PDFBackground: The course of multiple sclerosis (MS) shows substantial inter-individual variability. The underlying determinants of disease severity likely involve genetic and environmental factors.
Objective: The aim of this study was to assess the impact of APOE and HLA polymorphisms as well as smoking and body mass index (BMI) in the very early MS course.
Purpose To perform a direct metabolic comparison of chronic lesions and diffusely injured normal-appearing white matter (NAWM) in multiple sclerosis (MS). Materials and Methods In this institutional review board-approved study, with the written informed consent of all patients, two-dimensional magnetic resonance spectroscopic imaging data in 46 patients with relapsing-remitting MS (median disease duration, 0.8 year) were analyzed by using the spectral quantification tool LCModel.
View Article and Find Full Text PDFBackground: The pathology of multiple sclerosis (MS) consists of demyelination and neuronal injury, which occur early in the disease; yet, remission phases indicate repair. Whether and how the central nervous system (CNS) maintains homeostasis to counteract clinical impairment is not known.
Objective: We analyse the structural connectivity of white matter (WM) and grey matter (GM) networks to understand the absence of clinical decline as the disease progresses.
White matter (WM) lesions with a distinct lesion-tissue contrast are the main radiological hallmark of multiple sclerosis (MS) in standard magnetic resonance imaging (MRI). Pathological WM changes beyond lesion development lack suitable contrasts, rendering the investigation of normal appearing WM (NAWM) more challenging. In this study, repeat quantitative MRI (qMRI) was collected in 9 relapsing remitting MS patients with mild disease over nine months.
View Article and Find Full Text PDFA concern for researchers planning multisite studies is that scanner and T1-weighted sequence-related biases on regional volumes could overshadow true effects, especially for studies with a heterogeneous set of scanners and sequences. Current approaches attempt to harmonize data by standardizing hardware, pulse sequences, and protocols, or by calibrating across sites using phantom-based corrections to ensure the same raw image intensities. We propose to avoid harmonization and phantom-based correction entirely.
View Article and Find Full Text PDFObjectives: Fatigue is a common symptom in multiple sclerosis (MS) patients, even early in the disease, but the pathophysiology remains unclear. We aimed to determine morphologic and microstructural correlates and neuropsychological parameters of cognitive fatigue in early relapsing-remitting MS patients.
Methods: Seventy-nine early relapsing-remitting MS patients (38 with fatigue and 41 without), none of whom suffered from depression, underwent neuropsychological testing.
J Neural Transm (Vienna)
October 2015
Typical multiple sclerosis (MS) lesions occur in the brain as well as in the spinal cord. However, two extreme magnetic resonance imaging phenotypes appear occasionally: those with predominantly spinal cord lesions (MS + SL) and those with cerebral lesions and no detectable spinal lesions (MS + CL). We assessed whether morphological differences can be found between these two extreme phenotypes.
View Article and Find Full Text PDFThe use of non-routine MRI sequences such as DIR has highlighted the role of gray matter (GM) pathology in multiple sclerosis (MS). The aim of this study was to assess the detection and relevance of cortical lesions (CLs) using MRI in early (<5 years) MS patients. 3D DIR and 3D FLAIR images at 3T from 122 patients [93 relapsing-remitting MS (RRMS), 29 clinically isolated syndrome (CIS)] were scored for CLs by two blinded readers.
View Article and Find Full Text PDFAn increasing number of complications after penis enlargement procedures, sometimes self-performed, are being observed in Germany and in the other countries. This report presents a case of a 43-year-old patient who presented with multiple fistulas, paraffinomas and bacterial superinfection after having injected petroleum jelly into his penis. In order to remove the foreign bodies as well as the infected and necrotic tissue the complete epithelium had to be radically excised.
View Article and Find Full Text PDFHandchir Mikrochir Plast Chir
April 2015
Background: Mammography for the detection of early stage breast cancer is widely established. Breast-conserving therapy followed by radiation therapy is the most common therapy for early stage breast cancer. Due to the increasing use of radiation therapy in breast cancer, secondary neoplasia are induced.
View Article and Find Full Text PDFObjectives: Metabolic changes in the substantia nigra of patients with Parkinson's disease were previously investigated in different molecular-pathological examinations. The aim of our study was the in vivo measurement of these alterations using three-dimensional magnetic resonance spectroscopic imaging.
Methods: 21 patients with Parkinson's disease and 24 controls were examined using magnetic resonance spectroscopic imaging at 3 Tesla.
Progressive supranuclear palsy (PSP) is the most common atypical parkinsonian syndrome comprising two main clinical subtypes: Richardson's syndrome (RS), characterized by prominent postural instability, supranuclear vertical gaze palsy and frontal dysfunction; and PSP-parkinsonism (PSP-P) which is characterized by an asymmetric onset, tremor and moderate initial therapeutic response to levodopa. The early clinical features of PSP-P are often difficult to discern from idiopathic Parkinson's disease (PD), and other atypical parkinsonian disorders, including multiple system atrophy (MSA) and corticobasal syndrome (CBS). In addition, rare PSP subtypes may be overlooked or misdiagnosed if there are atypical features present.
View Article and Find Full Text PDFObjectives: Degeneration of dopaminergic neurons in the substantia nigra (SN) pars compacta is the primary cause of idiopathic Parkinson's disease (iPD). In early stages of disease in particular, presentation of symptoms is non-specific leading to difficulties in differentiating between iPD and atypical parkinsonian syndromes (aPS). The aim of this study was to evaluate the feasibility of three-dimensional magnetic resonance spectroscopic imaging (MRSI) of the SN region for differentiation between iPD and aPS.
View Article and Find Full Text PDFJ Neural Transm (Vienna)
December 2012
A central role of iron in the pathogenesis of Parkinson's disease (PD) has been discussed for many years. Numerous studies using magnetic resonance imaging and transcranial sonography have been performed to detect alterations in tissue iron content of the substantia nigra. This manuscript reviews the findings of this still controversial issue and indicates that specific abnormalities that are suggested to be related to a disturbance of iron homeostasis may play an early role in the pathogenesis of PD.
View Article and Find Full Text PDFThe neurotoxin 6-hydroxydopamine (6-OHDA) is frequently used in animal models to mimic Parkinson's disease. Imaging studies describe hyperintense signalling in regions close to the site of the 6-OHDA injection in T2-weighted (T2w) magnetic resonance imaging (MRI). The nature of this hyperintense signal remains elusive and still is matter of discussion.
View Article and Find Full Text PDFThe objective of this research was to evaluate a possible endophenotype in leucine-rich repeat kinase 2 (LRRK2)-associated Parkinson's disease (PD). Ten symptomatic LRRK2 patients, 24 sporadic Parkinson's disease patients as well as 10 asymptomatic LRRK2 mutation carriers and 29 matched healthy controls underwent comprehensive clinical assessments with respect to motor and non-motor symptoms. Transcranial sonography and magnetic resonance imaging (voxel-based morphometry [VBM]) were assessed to evaluate morphological imaging characteristics.
View Article and Find Full Text PDFObjectives: To investigate the substantia nigra in patients with Parkinson's disease three-dimensional magnetic resonance spectroscopic imaging with high spatial resolution at 3 Tesla was performed. Regional variations of spectroscopic data between the rostral and caudal regions of the substantia nigra as well as the midbrain tegmentum areas were evaluated in healthy controls and patients with Parkinson's disease.
Methods: Nine patients with Parkinson's disease and eight age- and gender-matched healthy controls were included in this study.
J Neural Transm (Vienna)
August 2011
Richardson's syndrome (RS) and progressive supranuclear palsy-parkinsonism (PSP-P) are the most common subtypes of PSP. Post-mortem data suggests that the clinical presentation of the two subtypes differs especially in the first 2 years of disease and then converges. This hypothesis has, to our knowledge, never been confirmed in a living cohort.
View Article and Find Full Text PDFSportverletz Sportschaden
June 2010
Due to the fast and physical nature of the game, prevention of injuries is an important issue in ice hockey. The injuries of the German male senior and junior (U16, U17, U18, U19, U20) national ice hockey teams were documented and analyzed in 1006 games between 1986 and 2006. This unique long observation period over 20 years, as well as the standardized protocol of documentation provides reliable data concerning injury pattern in German international ice hockey.
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