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PubMed2004

MIPAS-ENVISAT limb-sounding measurements: trade-off study for improvement of horizontal resolution.

The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) is a limb-scanning spectrometer that has operated onboard the Environmental Satellite since the end of March 2002. Common features of limb-scanning experiments are both high vertical resolution and poor horizontal resolution. We exploit the two-dimensional geo-fit retrieval approach [Appl. Opt. 40, 1872-1875 (2001)] to investigate the possibility of improving the horizontal resolution of MIPAS measurements. Two different strategies are considered for this purpose, one exploiting the possibility (offered by the geo-fit analysis method) for an arbitrary definition of the retrieval grid, the other based on the possibility of saving measurement time by degrading the spectral resolution of the interferometer. The performances of the two strategies are compared in terms of the trade-off between the attained horizontal resolution and the retrieval precision. We find that for ozone it is possible to improve by a factor of 2 the horizontal resolution, which in the nominal measurement plan is approximately 530 km. This improvement corresponds to a degradation of the retrieval precision, which on average varies from a factor of 1.4 to 2.5, depending on the adopted spectral resolution.

Journal Article↗

PubMed2006

Zoom lens design for a novel imaging spectrometer that controls spatial and spectral resolution individually.

A novel imaging spectrometer can individually control spatial and spectral resolution by using zoom lenses as the foreoptics of the system and a focusing lens. By varying the focal length we can use the focusing lens to change the spatial and spectral dimensions; with the foreoptics, however, we can change only the spatial dimension. Therefore the spectral resolution and the spectral range are affected by the zoom ratio of the focusing lens, whereas the spatial resolution and the field of view are affected by the multiplication of the zoom ratios of the foreoptics and the focusing lens. By properly combining two zoom ratios, we can control the spectral resolution with a fixed spatial resolution or the spatial resolution with a fixed spectral resolution. For an imaging spectrometer with this novel zooming function, we used the lens module method and third-order aberration theory to design an initial four-group zoom system with an external entrance pupil for the focusing lens. Furthermore, using the optical design software CODE V, we obtained an optimized zoom lens with a focal-length range of 50 to 150 mm. Finally, the zoom system with its transmission grating in the Littrow configuration performs satisfactorily as the focusing lens of an imaging spectrometer in the wavelength range 450-900 nm.

Journal Article↗

PubMed1994

Resolution of annular-pupil optical systems.

The resolution of optical systems with annular pupil objectives is discussed, particularly with respect to the imaging properties of soft-x-ray imaging optical systems. Images of two dark bars in a bright field and knife-edge responses, which are calculated with partially coherent transfer functions, were used to estimate the resolution. Resolution for two bright points in a dark field, which is conventionally used in Rayleigh's analysis, is also discussed for comparison. It was found that annular systems with obstruction ratios of more than 0.6 show resolution properties different from those of systems with low-obstruction-ratios. The high-obstruction-ratio systems show lower resolution for the two-dark-bar objects and higher resolution for the two-bright-point objects, whereas the low-obstruction-ratio system show almost the same resolution for both objects.

Light↗

PubMed2002

Variable-resolution displays: a theoretical, practical, and behavioral evaluation.

Variable-resolution display techniques present visual information in a display using more than one resolution. For example, gaze-contingent variable-resolution displays allocate computational resources for image generation preferentially to the area around the center of gaze, where visual sensitivity to detail is the greatest. Using such displays reduces the amount of computational resources required as compared with traditional uniform-resolution displays. The theoretical benefits, implementational issues, and behavioral consequences of variable-resolution displays are reviewed. A mathematical analysis of computational efficiency for a two-region variable-resolution display is conducted. The results are discussed in relation to applications that are limited by computational resources, such as virtual reality, and applications that are limited by bandwidth, such as internet image transmission. The potential for variable-resolution display techniques as a viable future technology is discussed.

Attention↗

PubMed2005

[Institutional Review Boards: compliance with Resolution 196/96].

PURPOSE: This article intends to evaluate the structure, functioning and performance of 17 Institutional Review Boards (IRB), from the viewpoint of their presidents, in relation to the instructions of Resolution 196/96 of the National Council of Health, Ministry of Health, Brazil. METHODS: Presidents of 33 IRBs, that evaluated proposals for research on fertility control, were indicated by the professionals responsible for the area of gynecology in 46 Brazilian medical schools and by the directors of four research centers on human reproduction . A letter with a questionnaire were sent to the presidents, asking them to volunteer for the study. RESULTS: Seventeen presidents completed the questionnaire. Results disclosed a series of violations of Resolution 196/96. Three IRBs did not include representatives of the community among their members; four took over a month to release the Board's decision on proposals and 13 did not follow-up the studies. Composition and filing of the research proposals were in agreement with the Resolution. However, in eight IRBs time of mandate differed from that set forth in the Resolution. Almost all presidents (about 14 of the 17) thought that the composition and activities of their IRBs were adequate. Eleven considered the Resolution appropriate but difficult to comply with. CONCLUSION: These results suggest that an extensive debate on the operational viability of the Resolution would be timely. This endeavor could bring forth valuable suggestions for the improvement and applicability of the Resolution contributing to the improvement of the scientific and ethical quality of research.

Brazil↗

PubMed1995

Reconstructed helical CT scans: improvement in z-axis resolution compared with overlapped and nonoverlapped conventional CT scans.

OBJECTIVE: This in vitro study was designed to assess the z-axis resolving capabilities of reconstructed helical CT scans obtained with various imaging parameters versus those of conventional CT scans and the effect of decreasing slice index on the z-axis resolution of helical CT. MATERIALS AND METHODS: A z-axis line-pair phantom was imaged using conventional nonoverlapped CT scans, conventional CT scans that overlapped by 50%, and helical CT scans with pitches of 1.0 and 1.5. All helical images were reconstructed at comparable slice indexes (image indexes of 2.0, 1.0, and 0.5 mm for pitch = 1.0, and image indexes of 3.0, 1.5, and 0.75 mm for pitch = 1.5). Midline coronal and sagittal reconstructed images were obtained to allow standardized visualization of line pairs. The reconstructed images were reviewed separately by 10 radiologists. RESULTS: The overall z-axis resolution of reconstructed helical CT scans equaled or exceeded that of nonoverlapped conventional CT scans in all cases and equaled that of 50% overlapped conventional CT scans in 75% of cases. The 1.0-pitch helical sequences showed improved z-axis resolution with decreasing slice index. No statistically significant improvement in z-axis resolution could be determined by the observers for 1.5-pitch sequences with decreasing slice index. CONCLUSION: The use of helical CT with a pitch of 1.0 or 1.5 and an increased slice index can improve the z-axis resolution of reconstructed images when compared with nonoverlapped conventional CT and frequently equals the resolution of 50% overlapped conventional CT. This improvement in z-axis resolution should improve the appearance of reconstructed images (as used in CT angiography and three-dimensional imaging) by reducing partial volume artifacts while affording faster scanning at a reduced skin-surface radiation dose.

Humans↗

PubMed1999

High-resolution CT findings of diffuse bronchioloalveolar carcinoma in 38 patients.

OBJECTIVE: The purpose of this study was to analyze the high-resolution CT features of diffuse bronchioloalveolar carcinoma and determine the useful findings in differential diagnosis. MATERIALS AND METHODS: High-resolution CT scans of 38 patients with pathologically proven diffuse bronchioloalveolar carcinoma were reviewed. Sequential CT scans were obtained in 15 patients. The high-resolution CT findings were compared with those of eosinophilic pneumonia (n = 22), multiple pulmonary metastases (n = 12), and tuberculosis (bronchogenic: n = 22; miliary: n = 12). RESULTS: High-resolution CT findings of diffuse bronchioloalveolar carcinoma included ground-glass opacity (n = 29), consolidation (n = 29), nodules (n = 28), centrilobular nodules (n = 26), peripheral distribution (n = 19), and air bronchogram (n = 18). According to the major features, high-resolution CT findings of diffuse bronchioloalveolar carcinoma could be classified into three patterns: predominantly ground-glass (n = 4), consolidative (n = 22), and multinodular (n = 12). Most patients with diffuse bronchioloalveolar carcinoma had a mixture of these findings. The frequency of findings of diffuse bronchioloalveolar carcinoma on high-resolution CT was not different from that of tuberculosis, but the predominant distribution of the nodules and areas of ground-glass attenuation differed between the two. Difference in distribution between bronchioloalveolar carcinoma and bronchogenic tuberculosis included ground-glass opacity remote from the consolidation and a lower lung predominance. CONCLUSION: Although these high-resolution CT findings are not specific, the combination of consolidation and nodules and the coexistence of centrilobular nodules and remote areas of ground-glass attenuation are characteristic of diffuse bronchioloalveolar carcinoma.

Adenocarcinoma, Bronchiolo-Alveolar↗

PubMed1990

Frequency selectivity and temporal resolution in patients with various inner ear disorders.

Both frequency selectivity and temporal resolution were examined in patients with various inner ear disorders. These included noise-induced hearing loss (n = 24), Menière's disease (n = 16), sudden deafness (n = 25), toxic inner ear damage (n = 14), presbyacusis (n = 38) and degenerative progressive inner ear hearing loss (n = 8). To facilitate quantitative comparison, various factors were introduced, namely, frequency resolution factor (FRF), temporal resolution factor (TRF) and a combined resolution factor (FTRF). The FRF of normal-hearing subjects in background noise conditions was found to be approximately 20% less than in comparative test conditions without noise, whereas the TRF of normal-hearing persons tested under background noise conditions showed a remarkable increase (factor 3). The frequency resolution performance and/or the temporal resolution performance were found to be impaired in all patient groups with inner ear hearing loss. This is particularly noticeable for temporal resolution in test conditions involving the addition of background noise. It can be concluded that in such cases, speech discrimination can be seriously jeopardized.

Hearing↗

PubMed1996

High-resolution fluorescence in situ hybridization: a new approach in genome mapping.

Mapping of the human genome has been a global effort utilizing both genetic and physical mapping techniques. One approach which has greatly facilitated the physical mapping of the human genome is fluorescence in situ hybridization (FISH). Although FISH is by now a well-established technology, new recently developed modifications have enabled an easier use and higher resolution. The high-resolution FISH techniques have given a special impact in positional cloning: searching the functional gene from a chromosomal area where the gene has been genetically localized. New high-resolution FISH techniques include hybridization of probes to free chromatin, DNA fibres or mechanically stretched chromosomes. These targets have widened the resolution of FISH to detect distances from the traditional cytogenetic resolution level down to a resolution of a few kilobases. They also have significantly speeded up high-resolution physical mapping and thus made the search of new disease genes easier.

Chromosome Mapping↗

PubMed1989

Chromosome preparation and high resolution banding techniques. A review.

High resolution banding techniques enable detection of chromosome rearrangements even within major bands. Banded chromosomes prepared for light microscopic studies of intact metaphase plates are, however, highly modified structures compared with native chromosomes, and the high resolution banding techniques only seem possible because the following methods were standardized and combined. The use of colcemid, which prevents formation of the spindle and thereby collects cells at the metaphase-anaphase border, is routinely used for chromosome preparations. For high resolution banding studies, short exposure time and concentrations near the threshold value have been recommended by several authors. Several agents interfere with chromosome contraction processes, but only a few have had a lasting influence on high resolution banding studies. The most used agents are ethidium bromide, actinomycin D, and Hoechst 33258, which all partially inhibit chromosome contraction. Treatment with hypotonic solutions induces swelling of animal cells, and the methanol in the fixative denatures and precipitates protein by dehydration. The acetic acid coagulates nucleoproteins and causes swelling of the cells. The fixative penetrates the cells rapidly and preserves the chromosome structure. To obtain long segmented chromosomes suitable for high resolution banding hypotonic treatment with .075 M KCl, frequent changes of fixative and overnight fixation at 4 degrees C have been recommended. The use of cell synchronization, 5-bromodeoxyuridine incorporation into DNA, and fluorochrome-photolysis Giemsa (FPG)-staining have improved the quality of high resolution banding. Synchronization techniques, which select for lymphocyte populations in early divisions, provide excellent materials for chromosome preparations and induction of high resolution banding. The banding techniques seem to enhance differences already present in the chromosomes, and the differential Giemsa staining has recently been explained by interactions between the hydrophobic dye complex, the supercoiled DNA helix, and the denaturated histone core of the nucleosomes.

Animals↗

PubMed2002

Vertical meridian asymmetry in spatial resolution: visual and attentional factors.

We investigated whether spatial resolution would be the same in the lower and upper halves of the vertical meridian (VM) of our visual field and whether attention would affect them differentially. It has been reported that (1) attending to the target's location improves performance in a texture segregation task when the observer's spatial resolution is too low (peripheral locations) but impairs it when resolution is already too high (central locations) for the task. This finding indicates an enhanced spatial resolution at the attended location (Yeshurun & Carrasco, 1998,2000), (2) observers' contrast sensitivity is higher in the lower than in the upper VM, a phenomenon known as vertical meridian asymmetry (VMA), an asymmetry determined by visual rather than by attentional factors (Carrasco, Talgar, & Cameron, 2001). In the present texture segregation task, performance was assessed under neutral- and peripheral-cue conditions. Transient covert attention was systematically manipulated by using a peripheral cue that indicated the target's location and its onset. Observers reported the interval containing a target patch appearing at one of a number of eccentricities in a large texture pattern along the VM. We found that (1) performance peaked at farther eccentricities in the lower than in the upper visual VM, indicating that resolution was higher in the lower half, and (2) the peripheral cue affected performance along the VM uniformly, indicating that the degree of enhanced resolution brought about by transient attention was constant along the VM. Thus, we conclude that the VMA for spatial resolution is determined by visual, not transient covert attentional, constraints.

Adult↗

PubMed2004

Resolution of left atrial thrombus after 6 months of anticoagulation in candidates for percutaneous transvenous mitral commissurotomy.

BACKGROUND: Resolution of left atrial thrombus after long-term oral anticoagulation enhances safe percutaneous transvenous mitral commissurotomy (PTMC); however, the short-term benefit has not been defined. OBJECTIVES: To estimate the resolution rate of left atrial thrombus among PTMC candidates after 6 months of oral anticoagulation and to determine its main predictors. DESIGN: Prospective cohort. SETTING: Community-based university medical center. PATIENTS: 219 PTMC candidates with thrombus demonstrated by multiplane transesophageal echocardiographic studies. MEASUREMENTS: The primary outcome was the status of the thrombus at the first 6-month follow-up; secondary measures were bleeding or thromboembolic complications. RESULTS: Among 219 PTMC candidates with left atrial thrombus (mean age [+/-SD], 39.6 +/- 7.4 years [range, 19 to 62 years]), complete resolution of thrombus, with an overall disappearance rate of 24.2% (95% CI, 18.5% to 29.9%), was demonstrated in 53 patients who subsequently underwent successful PTMC. In another 166 patients, the thrombus size was reduced by 24% (P < 0.001). No thrombus resolution was observed in the 27 patients with a left atrial body thrombus. Eighteen patients had minor bleeding. The significant predictors of thrombus resolution were a New York Heart Association class of 2 or less, a left atrial appendage thrombus size of 1.6 cm2 or less, a left atrial spontaneous echocardiographic contrast grade of 1 or less, and an international normalized ratio (INR) of at least 2.5. Patients with all of these predictors had a 94.4% chance of complete thrombus resolution (CI, 84.4% to 98.1%). CONCLUSIONS: After 6 months of oral anticoagulation, the left atrial thrombus disappeared in about a quarter of PTMC candidates so they could safely undergo PTMC. Less clinical severity, lower grading of the left atrial spontaneous echocardiographic contrast, a smaller thrombus, and a higher INR level predict thrombus resolution.

Adult↗

PubMed1998

Thyroid palpation versus high-resolution thyroid ultrasonography in the detection of nodules.

Detection of thyroid nodules by physical examination and high-resolution ultrasonography was compared using small groups of blinded, experienced physician examiners working with a sample of 2441 persons from Estonia, most of whom were Chernobyl nuclear reactor clean-up workers. A random subsample of 113 (5%) persons was subjected to triple control examinations with both physical examination and high-resolution ultrasonography. Positive high-resolution ultrasonographic findings were considerably more reproducible among different observers than were positive physical examination findings. Agreement between methods was poor. Nodules were found in 169 (6.9%) subjects by physical examination and in 249 (10.2%) subjects by high-resolution ultrasonography. Physical examination found only 53 (21%) of the 249 nodules found by high-resolution ultrasonography. High-resolution ultrasonography did not confirm the existence of 115 (68%) of the 169 nodules found by physical examination. Only 6.4% of nodules less than 0.5 cm in diameter, as based on high-resolution ultrasonographic results, were detected by physical examination. Physical examination detection improved with increasing nodule size but was still only 48.2% for nodules larger than 2 cm. Physical examination was relatively effective in detecting nodules in the isthmus of the thyroid gland but much less so for nodules in the upper pole of the gland. Clinical evaluation and epidemiologic studies of nodular thyroid disease stand to benefit from the greater sensitivity and specificity of ultrasonographic examinations.

Adolescent↗

PubMed1999

Performance evaluation of microPET: a high-resolution lutetium oxyorthosilicate PET scanner for animal imaging.

UNLABELLED: A new dedicated PET scanner, microPET, was designed and developed at the University of California, Los Angeles, for imaging small laboratory animals. The goal was to provide a compact system with superior spatial resolution at a fraction of the cost of a clinical PET scanner. METHODS: The system uses fiberoptic readout of individually cut lutetium oxyorthosilicate (LSO) crystals to achieve high spatial resolution. Each microPET detector consists of an 8 x 8 array of 2 x 2 x 10-mm LSO scintillation crystals that are coupled to a 64-channel photomultiplier tube by optical fibers. The tomograph consists of 30 detectors in a continuous ring with a 17.2-cm diameter and fields of view (FOVs) of 11.25 cm in the transaxial direction and 1.8 cm in the axial direction. The system has eight crystal rings and no interplane septa. It operates exclusively in the three-dimensional mode and has an electronically controlled bed that is capable of wobbling with a radius of 300 microm. We describe the performance of the tomograph in terms of its spatial, energy and timing resolution, as well as its sensitivity and counting-rate performance. We also illustrate its overall imaging performance with phantom and animal studies that demonstrate the potential applications of this device to biomedical research. RESULTS: Images reconstructed with three-dimensional filtered backprojection show a spatial resolution of 1.8 mm at the center of the FOV (CFOV), which remains <2.5 mm for the central 5 cm of the transaxial FOV. The resulting volumetric resolution of the system is <8 microL. The absolute system sensitivity measured with a 0.74 MBq (20 microCi) 68Ge point source at the CFOV is 5.62 Hz/kBq. The maximum noise equivalent counting rate obtained with a 6.4-cm diameter cylinder spanning the central 56% of the FOV is 10 kcps, whereas the scatter fraction is 37% at the CFOV for an energy window of 250-650 keV and the same diameter cylinder. CONCLUSION: This is the first PET scanner to use the new scintillator LSO and uses a novel detector design to achieve high volumetric spatial resolution. The combination of imaging characteristics of this prototype system (resolution, sensitivity, counting-rate performance and scatter fraction) opens up new possibilities in the study of animal models with PET.

Animals↗

PubMed2000

Relative impact of scatter, collimator response, attenuation, and finite spatial resolution corrections in cardiac SPECT.

UNLABELLED: We determined the relative effect of corrections for scatter, depth-dependent collimator response, attenuation, and finite spatial resolution on various image characteristics in cardiac SPECT. METHODS: Monte Carlo simulations and real acquisition of a 99mTc cardiac phantom were performed under comparable conditions. Simulated and acquired data were reconstructed using several correction schemes that combined different methods for scatter correction (3 methods), depth-dependent collimator response correction (frequency-distance principle), attenuation correction (nonuniform Chang correction or within an iterative reconstruction algorithm), and finite spatial resolution correction (use of recovery coefficients). Five criteia were considered to assess the effect of the processing schemes: bull's-eye map (BEM) uniformity, contrast between the left ventricle (LV) wall and the LV cavity, spatial resolution, signal-to-noise ratio (SNR), and percent errors with respect to the known LV wall and liver activities. RESULTS: Similar results were obtained for the simulated and acquired data. Scatter correction significantly improved contrast and absolute quantitation but did not have noticeable effects on BEM uniformity or on spatial resolution and reduced the SNR. Correction for the depth-dependent collimator response improved spatial resolution from 13.3 to 9.5 mm in the LV region, improved absolute quantitation and contrast, but reduced the SNR. Correcting for attenuation was essential for restoring BEM uniformity (78% and 89% without and with attenuation correction, respectively [ideal value being 100%]) and accurate absolute activity quantitation (errors in estimated LV wall and liver activity decreased from 90% without attenuation correction to approximately20% with attenuation correction only). Although accurate absolute activity quantitation was achieved in the liver using scatter and attenuation corrections only, correction for finite spatial resolution was needed to estimate LV wall activity within 10%. CONCLUSION: The respective effects of corrections for scatter, depth-dependent collimator response, attenuation, and finite spatial resolution on different image features in cardiac SPECT were quantified for a specific acquisition configuration. These results give indications regarding the improvements to be expected when using a specific processing scheme involving some or all corrections.

Heart↗

PubMed1975

Effect of positron range on spatial resolution.

The effect of beta+ range on spatial resolution of imaging systems employing the detection of 511-keV annihilation radiation was determined by measuring the variation in the line-spread functions (LSFs) of positron-emitting radionuclides of 64Cu, 11C, and 15O as compared with the 514-keV gamma-ray emitter 85Sr. These radionuclides have maximum beta+ energies of 0.656, 0.960, and 1.72 MeV, respectively. The LSFs were measured in a tissue-equivalent phantom with high-resolution (approximately 2.4 mm FWHM) and low-resolution (approximately 8.8 mm FWHM) straightbore collimators coupled to a NaI(Tl) detector. Theoretical LSFs for the beta+ ranges were also calculated and convolved with the 85Sr LSF to yield the predicted LSFs for 11C and 15O. The high-resolution study showed a 0% and 2.3% increase in the full-width half-maximum (FWHM) and full-width tenth-maximum (FWO.1M) for the low-energy beta+ of 64Cu and a 37% (FWHM) and 52% (FWO.1M) increase for the high energy beta+ of 15O as compared with 85Sr. However, when the system resolution was decreased to 8.8 mm FWHM, the 64Cu showed no change at FWHM or FWO.1M and the 15O showed a 2.3% (FWHM) and 7.8% (FWO.1M) relative to 85Sr. The predicted LSFs were in good agreement with the experimental. These data indicate that the effect of beta+ range on spatial resolution is minimal unless the beta+ energy is larger than or equal to 1.5 MeV and the system resolution is on the order of a few millimeters.

Carbon Radioisotopes↗

PubMed1995

[The spatial resolution of the digital storage phosphor system. The monitor and film compared].

The physical characteristics of radiographic images, namely spatial resolution and contrast, have obvious effects upon diagnostic image usefulness. We investigated the spatial resolution of both radiographs and magnified digital obtained with a storage phosphor system, in comparison with a film-screen combination. This study was carried out on the conventional radiographs of a phantom grid 0.5 mm thick, with resolution ranging from 0.5 to 10 lp/mm. Each examination was compared at naked eye and with the electronic evaluation of a region of interest on both standard and magnified views or by digitization with a charge coupled detector (CCD) television camera followed by the computing of the modulation transfer function curve. Our results demonstrate a higher spatial resolution of direct magnification, on both digital and film-screen pictures (over 5 lp/mm). On the contrary, the electronic magnification on the monitor yields the same spatial resolution as non-magnified digital images (up to 4.3 lp/mm). By selecting appropriate regions of interest, we could demonstrate the compression of the non-magnified images on the monitor. The modulation transfer curves show that direct magnification yields higher spatial resolution than electronic magnification and non-magnified views. Viewing electronically magnified images on the monitor yields the same resolution as contact radiographs: the monitor offers the advantage of an easier study of the regions of interest.

Evaluation Studies as Topic↗

PubMed1996

Near-field confocal optical spectroscopy (NCOS): subdiffraction optical resolution for biological systems.

Optical resolution is limited by diffraction. However, in near-field microscopes sample illumination is provided through a subwavelength aperture to increase optical resolution. In this study we have evaluated the usefulness of this technique for living biological systems and report two significant improvements in this form of microscopy to enhance optical resolution for biological studies. We report a unique feedback method, photon-density feedback, which is used to monitor the registration of a near-field illumination probe with living cell membranes. In this method, the fluorescence intensity of a uniformly distributed fluorochrome is monitored while the sample is moved in the z-axis towards the probe. Upon contact between the cell membrane and the near-field probe a maximum intensity is detected. A problem with near-field microscopy is that enhanced optical resolution is only achieved within the near-field of the illuminating aperture. Thick biological specimens also fluoresce in the far-field reducing optical resolution. To reduce this problem we incorporated a confocal pinhole together with the near-field probe to enhance the resolution of this form of near-field microscopy. Finally, we demonstrate that near-field confocal optical spectroscopy does not impair physiological properties of neurons, astrocytes or mast cells, indicating that this high-resolution optical methodology will permit a new approach to the study of molecular distribution and action within living specimens.

Aniline Compounds↗