Miniature in vivo MEMS-based line-scanned dual-axis confocal microscope for point-of-care pathology.

There is a need for miniature optical-sectioning microscopes to enable in vivo interrogation of tissues as a real-time and noninvasive alternative to gold-standard histopathology. Such devices could have a transformative impact for the early detection of cancer as well as for guiding tumor-resection procedures. Miniature confocal microscopes have been developed by various researchers and corporations to enable optical sectioning of highly scattering tissues, all of which have necessitated various trade-offs in size, speed, depth selectivity, field of view, resolution, image contrast, and sensitivity.

A coherent model for turbid imaging with confocal microscopy.

We present an engineering model of coherent imaging within a turbid volume, such as human tissues, with a confocal microscope. The model is built to analyze the statistical effect of aberrations and multiply scattered light on the resulting image. Numerical modeling of theory is compared with experimental results.

Optimal detection pinhole for lowering speckle noise while maintaining adequate optical sectioning in confocal reflectance microscopes.

Coherent speckle influences the resulting image when narrow spectral line-width and single spatial mode illumination are used, though these are the same light-source properties that provide the best radiance-to-cost ratio. However, a suitable size of the detection pinhole can be chosen to maintain adequate optical sectioning while making the probability density of the speckle noise more normal and reducing its effect. The result is a qualitatively better image with improved contrast, which is easier to read.

Near-IR fluorescence and reflectance confocal microscopy for imaging of quantum dots in mammalian skin.

Understanding the skin penetration of nanoparticles (NPs) is an important concern due to the increasing presence of NPs in consumer products, including cosmetics. Technical challenges have slowed progress in evaluating skin barrier and NP factors that contribute to skin penetration risk. To limit sampling error and other problems associated with histological processing, many researchers are implementing whole tissue confocal or multiphoton microscopies.

Modulation transfer function measurement of scanning reflectance microscopes.

Real-time medical imaging systems such as reflectance confocal microscopes and optical coherence microscopes are being tested in multiple-patient and multiple-center clinical trials. The modulation transfer function (MTF) of these systems at any given time influences the image information content and can affect the interpretation of the images. MTF is difficult to measure in real-time scanning systems when imaging at the Nyquist limit.

[Spinocerebellar ataxias type 1 and 2: comparison of clinical, electrophysiological and magnetic resonance evaluation].

Background And Purpose: Spinocerebellar ataxias type 1 (SCA1) and type 2 (SCA2) belong to neurodegenerative disorders of autosomal dominant inheritance, genetically and clinically heterogeneous, caused by the expansion of CAG trinucleotides. Trunk and limb ataxia, dysarthria, dysphagia, gaze palsy, sensory and motor axonal neuropathy are the dominant features in both entities. The aim of the study was to evaluate the differences between genotype and phenotype based on clinical and electrophysiological assessment of the visual, auditory pathways, and EEG alterations in comparison with the cerebellar and brain atrophy in MRI.

Impairment of the peripheral nervous system in Creutzfeldt-Jakob disease.

Background: The clinical manifestations of Creutzfeldt-Jakob disease (CJD) primarily reflect involvement of the central nervous system. The coexistence of CJD with peripheral nervous system involvement has also been reported.

Objective: To analyze peripheral neuron electrophysiologic changes and to compare these data with neuropathologic features of spinal motor neurons in patients with definite CJD.

Motor evoked potential studies in Creutzfeldt-Jakob disease.

Objectives: Motor evoked potentials (MEPs) were recorded in 7 cases of Creutzfeldt-Jakob disease (CJD) to asses the involvement of pyramidal motor pathways in these cases. The diagnosis of CJD was confirmed by autopsy in 5 cases and based on clinical data in two cases.

Methods: Transcranial (MEP-cortex), root magnetic (MEP-root) and electrical stimulation of peripheral nerves (F-wave, direct M-response) were performed.

Peculiarity of soleus motor potentials evoked by transcranial magnetic stimulation and electrical stimulation of tibial nerve.

Objective: To reveal and discuss the peculiarities of soleus muscle in comparison with electrophysiological features of other leg muscles.

Methods: Vastus lateralis (L3), tibialis anterior (L4), extensor digitorum brevis (L5) and soleus (S1) muscles were tested at rest. Transcranial magnetic stimulation (TMS) combined which electrical stimulation of relevant peripheral nerves were applied.

[Motor segmental conduction times for extensor digitorum brevis muscle: method and normative values].

Electrical stimulation of the peroneal nerves (60 nerves) and magnetic stimulation of the roots (L5) and motor cortex were performed on 30 normal controls. The muscle responses and F wave (peripheral stimulation) were recorded from extensor digitorum brevis muscle (60 muscles). The parameters of examined potentials were measured and the central, root, peripheral motor conduction times, were estimated.

[Segmental motor conduction time for abductor of the fifth finger muscle: methods and normative values].

Electrical stimulation of the ulnar nerves (60 nerves) and magnetic stimulation of the roots (C7) and motor cortex were performed on 30 normal controls. The muscle responses and F wave (peripheral stimulation) were recorded from abductor digiti minimi muscle (60 muscles). The parameters of examined potentials were measured and the central, root, peripheral motor conduction times were estimated.

Cortical excitability threshold for distal limb muscles in transcranial magnetic stimulation. Method--normative values.

Transcranial magnetic stimulation was carried out in 30 healthy subjects, aged 20 to 55 and 156 to 180 cm tall, in whom cortical excitability threshold was determined for musculus (m.) abductor digiti minimi (ADM) and m. extensor digitorum brevis (EDB).

Segmental conduction times in the motor nervous system.

The study was performed in 30 normal subjects (24 females and 6 males) with an age range between 18 and 55 years and a height range between 154 and 188 cm. Electrical stimulation was applied to the peroneal nerve with simultaneous recording of the orthodromic response (MEP-M) and F-wave (MEP-F) from the tibialis anterior (TA) and extensor digitorum brevis muscles (EDB). Magnetic stimulation of the L5 level and cerebral cortex was applied using different coils with simultaneous recording of responses from the right and left TA and EDB muscles.

[Segmental conduction times in motor pathways for the soleus muscle--methodology and normal values].

The study performed in 30 normal subjects (24F, 6M) with age range 18-55 years and height range 154-188 cm. Electrical stimulation was applied to the tibial nerves and direct response M and F-wave was recorded from right and left SOLEUS (60 examinations). Transcranial and paravertebral (S1 level) magnetic stimulation was applied with simultaneous recording of responses from both SOL.

The F-wave in the vastus lateralis M. and the segmental motor conduction times for L2/L4 motoneurons.

The study was performed in 30 normal subjects. Electrical stimulation was applied to the femoral nerves and the muscle evoked potential (CMAP) together with their late components were recorded from the vastus lateralis muscle bilaterally (60 nerves). Features of the late component demonstrating its antidromic nature (F-wave) were proved.

[Dermatomal somatosensory evoked potentials from L3, L4, L5 and S1 spinal roots in healthy subjects].

Dermatomal somatosensory evoked potentials (DSEPs) were recorded in 62 healthy volunteers aged from 15 to 65 years (mean 36.8 +/- 12.9 years) with height from 1.