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PubMed2004

Linear approach to axial resolution in elasticity imaging.

Thus far axial resolution in elasticity imaging has been addressed only empirically. No clear analytical approaches have emerged because the estimator is non-linear in the data, correlation functions are nonstationary, and system responses vary spatially. This paper describes a linear systems approach based on a small-strain impulse approximation that results in the derivation of a local impulse response (LIR) and local modulation transfer function (LMTF). Closed-form solutions for strain LIR are available to provide new insights on the role of instrumentation and processing on axial strain resolution. Novel phantom measurements are generated to validate results. We found that the correlation window determines axial resolution in most practical situations, but that the the same system properties that determine B-mode resolution ultimately limit elasticity imaging.

Animals↗

PubMed2004

Effects of noise, image resolution, and ROI definition on the accuracy of standard uptake values: a simulation study.

UNLABELLED: Semiquantitative standard uptake values (SUVs) are used for tumor diagnosis and response monitoring. However, the accuracy of the SUV and the accuracy of relative change during treatment are not well documented. Therefore, an experimental and simulation study was performed to determine the effects of noise, image resolution, and region-of-interest (ROI) definition on the accuracy of SUVs. METHODS: Experiments and simulations are based on thorax phantoms with tumors of 10-, 15-, 20-, and 30-mm diameter and background ratios (TBRs) of 2, 4, and 8. For the simulation study, sinograms were generated by forward projection of the phantoms. For each phantom, 50 sinograms were generated at 3 noise levels. All sinograms were reconstructed using ordered-subset expectation maximization (OSEM) with 2 iterations and 16 subsets, with or without a 6-mm gaussian filter. For each tumor, the maximum pixel value and the average of a 50%, a 70%, and an adaptive isocontour threshold ROI were derived as well as with an ROI of 15 x 15 mm. The accuracy of SUVs was assessed using the average of 50 ROI values. Treatment response was simulated by varying the tumor size or the TBR. RESULTS: For all situations, a strong correlation was found between maximum and isocontour-based ROI values resulting in similar dependencies on image resolution and noise of all studied SUV measures. A strong variation with tumor size of > or =50% was found for all SUV values. For nonsmoothed data with high noise levels this variation was primarily due to noise, whereas for smoothed data with low noise levels partial-volume effects were most important. In general, SUVs showed under- and overestimations of > or =50% and depended on all parameters studied. However, SUV ratios, used for response monitoring, were only slightly dependent of ROI definition but were still affected by noise and resolution. CONCLUSION: The poor accuracy of the SUV under various conditions may hamper its use for diagnosis, especially in multicenter trials. SUV ratios used to measure response to treatment, however, are less dependent on noise, image resolution, and ROI definition. Therefore, the SUV might be more suitable for response-monitoring purposes.

Computer Simulation↗

PubMed2004

Experimental flat-panel high-spatial-resolution volume CT of the temporal bone.

BACKGROUND AND PURPOSE: A CT scanner employing a digital flat-panel detector is capable of very high spatial resolution as compared with a multi-section CT (MSCT) scanner. Our purpose was to determine how well a prototypical volume CT (VCT) scanner with a flat-panel detector system defines fine structures in temporal bone. METHODS: Four partially manipulated temporal-bone specimens were imaged by use of a prototypical cone-beam VCT scanner with a flat-panel detector system at an isometric resolution of 150 microm at the isocenter. These specimens were also depicted by state-of-the-art multisection CT (MSCT). Forty-two structures imaged by both scanners were qualitatively assessed and rated, and scores assigned to VCT findings were compared with those of MSCT. RESULTS: Qualitative assessment of anatomic structures, lesions, cochlear implants, and middle-ear hearing aids indicated that image quality was significantly better with VCT (P < .001). Structures near the spatial-resolution limit of MSCT (e.g., bony covering of the tympanic segment of the facial canal, the incudo-stapedial joint, the proximal vestibular aqueduct, the interscalar septum, and the modiolus) had higher contrast and less partial-volume effect with VCT. CONCLUSION: The flat-panel prototype provides better definition of fine osseous structures of temporal bone than that of currently available MSCT scanners. This study provides impetus for further research in increasing spatial resolution beyond that offered by the current state-of-the-art scanners.

Artifacts↗

PubMed2004

Diagnostic value of high resolution computed tomography in the assessment of nodular changes in pneumoconiosis in foundry workers in Lublin.

The workers of an iron foundry were exposed to air pollution, which after some time of exposure results in lung fibrosis among some workers. The diagnosis of pneumoconiosis in workers of an iron foundry is based mainly on the radiological findings among workers exposed to the dust causing lung fibrosis. However, on radiograms many parenchymal structures overlap, which limits sensitivity and specificity to the method. Difficulties in accurate interpretation of conventional radiograms in silicosis also result from their relatively low resolution. The purpose of the present study was to assess the value and usefulness of high resolution computed tomography in the diagnostics of nodular changes in foundry workers' pneumoconiosis, compared to conventional radiography. The study group consisted of 64 iron foundry workers in whom silicosis had been recognized. The average age of the group was 51 years and the mean silica exposure time was 23 years. Chest radiograms with hard X-rays were taken at the maximal inspiration phase. For the HRCT examination the Siemens Somatom ART apparatus was used, equipped with a 512 x 512 pixels reconstruction matrix and a special programme for high resolution algorithm image reconstruction. In our material, consistency of results for conventional radiography and HRCT in revealing the presence of nodules was high. A statistically significant increase in detectability of intralobular nodules and peripheral nodules localized under the pleura was observed. The increase in detectability of cavernous, calcified nodules and those in the upper pulmonary fields obtained from computed tomography, however, was not statistically significant. High resolution computed tomography provides significant additional information in patients with foundry workers' pneumoconiosis.

Adult↗

PubMed2005

Frequency doubling illusion: detection vs. form resolution.

PURPOSE: To investigate the difference between detection and form resolution thresholds for the frequency doubling (FD) illusion. METHOD: The right eyes of 20 normal healthy subjects (10 female; age range, 18 to 30 years; mean age, 24.05 years; SD, 1.39) were examined. Vertically oriented FD stimuli were presented at fixation and 10 degrees nasally using a dual temporal alternate forced choice method of constant stimuli (2AFC MOCS) to estimate the thresholds for detection and form resolution. Additional strategies for threshold estimation (yes/no, modified rapid estimation by binary search) were used to determine the detection threshold. The effect of subject instruction on the FD threshold was also examined. The test-retest characteristics were investigated by determining the coefficient of repeatability. RESULTS: Detection thresholds using 2AFC MOCS were 0.86 +/- 0.20 (+/-1 SE) Michelson contrast percentage (MC%) at fixation and 0.84 +/- 0.21 at 10 degrees. Form resolution thresholds using 2AFC MOCS were 1.08 +/- 0.23 MC% at fixation and 1.04 +/- 0.16 at 10 degrees . These thresholds were found to be significantly different at fixation (p = 0.004) and 10 degrees (p = 0.005). No difference was found between threshold estimation strategies, but subject instruction had a significant effect (fixation: 2.41 +/- 0.52 MC%, p < 0.001; 10 degrees : 2.19 +/- 0.48 MC%, p < 0.001). CONCLUSIONS: Detection thresholds were significantly lower than form resolution thresholds for the FD stimulus. This result is in agreement with classic FD studies and illustrates that the perception of flicker precedes the perception of the FD illusion at threshold.

Adult↗

PubMed1992

[Normal bronchi on high resolution CT].

The delineation of normal bronchi was evaluated by high resolution CT. Under the usual conditions for lung survey, with window width of 1500, window level -650, and slice thickness 10 mm, using high spatial frequency algorithm, the subsegmental bronchi were delineated in 77% of total branches. Sub-subsegmental bronchi were delineated in 8% of branches. Under thin slice high resolution CT, with slice thickness of 1.5 mm and slice interval 10 mm, subsegmental bronchi were delineated in 89% of branches, and sub-subsegmental bronchi were delineated in 35% of branches. In two of the cases in which almost the whole lungs were studied on continuous slice images with thin slice high resolution CT, sub-sub-subsegmental bronchi could be easily delineated, except in for the lingular segment. High resolution CT is very useful for the interpretation of normal pulmonary structures and for diagnosis of bronchial lesions.

Adolescent↗

PubMed2005

PC VIPR: a high-speed 3D phase-contrast method for flow quantification and high-resolution angiography.

BACKGROUND AND PURPOSE: Three-dimensional phase-contrast (3DPC) is limited by long imaging times, limited coverage, flow artifacts, and the need to perform multiple additional 2D examinations (2DPC) to measure flow. A highly undersampled 3D radial acquisition (isotropic-voxel radial projection imaging [PCVIPR]) makes it possible to increase the product of volume coverage and spatial resolution by a factor of 30 for the same imaging time as conventional Cartesian 3DPC. This provides anatomic information over a large volume with high isotropic resolution and permits retrospective measurement of average flow rates throughout the volume. METHODS: PCVIPR acquires a reference and three flow-encoded acquisitions for each VIPR projection. Complex difference images were formed by combining information from all flow directions. Following retrospective definition of planes perpendicular to selected vessels, volume flow rates were determined by using phase-difference information. The accuracy of average flow measurement was investigated in a phantom and in six volunteers. Anatomic PCVIPR images acquired in three patients and three volunteers by using a 384(3) matrix were compared with conventional Cartesian 3DPC. RESULTS: The flow validation produced R2 = 0.99 in vitro and R2 = 0.97 in vivo. PCVIPR produced minimal streak and pulsatile flow artifacts. PCVIPR produced far higher resolution and volume coverage in comparable imaging times. The highest acceleration factors relative to 3DPC were achieved by using gadolinium-contrast material. Ultimately, acceleration factors are limited by signal-to-noise ratio. CONCLUSION: PCVIPR rapidly provides isotropic high-resolution angiographic images and permits retrospective measurement of average flow rate throughout the volume without the need to prescribe multiple 2D acquisition planes.

Adult↗

PubMed2005

Rapid resolution of cellulitis in patients managed with combination antibiotic and anti-inflammatory therapy.

There is some evidence to suggest that host inflammatory response has some effect on the clinical manifestations of cellulitis. The objective of this pilot study was to investigate whether the addition of oral nonsteroidal anti-inflammatory (NSAI) therapy to antibiotic treatment hastens resolution of cellulitis-related inflammation. Patients presenting in the emergency department with signs and symptoms of class II cellulitis were assigned to receive treatment with either antibiotic therapy alone (intravenous, supplemented with oral cephalexin or an equivalent) for 10 days (n = 33) or antibiotic therapy for 10 days plus an oral anti-inflammatory (ibuprofen 400 mg every 6 hours) for 5 days (n = 31). Patients were discharged as soon as possible to complete their therapy on an outpatient basis. The addition of an oral anti-inflammatory agent significantly (P < .05) shortened the time to regression of inflammation and complete resolution of cellulitis. Twenty-four of 29 evaluable patients (82.8%) who received supplemental anti-inflammatory treatment showed regression of inflammation within 1 to 2 days compared with only 3 of 33 patients (9.1%) treated without an anti-inflammatory in the same time frame. All patients receiving adjunctive anti-inflammatory treatment experienced complete resolution of cellulitis in 4 to 5 days or less, while 24.2% (8/33) of patients treated with antibiotic alone required 6 to 7 days, and 6.1% (2/33) required 7 days or more (P < .05). This small preliminary study provides some promising data, suggesting that the supplemental use of anti-inflammatory therapy may hasten the time to regression of inflammation and complete resolution of cellulitis.

Anti-Bacterial Agents↗

PubMed2005

[Value of ST-segment elevation resolution after primary coronary angioplasty in predicting early and late left ventricular function in patients with anterior acute myocardial infarction].

UNLABELLED: The aim of our study was to define a predictive value of ST-segment resolution after coronary reperfusion for early and late left ventricular (LV) function. We also studied its relation to angiographic marker of myocardial reperfusion, myocardial blush grade (MBG). MATERIALS AND METHODS: Study population consisted of 105 patients (75 men, 30 women, mean age 62+/-13 years) treated with primary PTCA for anterior myocardial infarction (AMI) within 12 hours from symptoms onset. ECG was performed before - and 30 min. after PTCA. We evaluated angiographic markers of recanalization (TIMI, corrected TIMI frame count) and myocardial reperfusion - MBG. Echocardiography was performed 3 days and 6 months after AMI. Patients were divided into 2 groups regarding reduction -50% in ST segment elevation after recanalization (rST): group I (n=37) with rST, and group 2 (n=68) without rST RESULTS: In group I we noticed higher CPK level (2890,2+/-2404,2 U/I vs. 3980,9+/-2812,2 U/I, p<0,01). MB grade 3 was significantly more often found in group 1 at 29 pts (78,4%) than in group 2 at 18 pts (23,5%), p<0,0001. MG grade 0 or 1 were more often in group 2 (57,3% vs. 2,7%, p<0,01). Ejection fraction (EF) was higher in group 1 after 3 days (48,9+/-9,5% vs. 44,2+/-14,3%, p<0,01), as well as after 6 months (56,4+/-14,4% vs. 49,5+/-14,3%, p=0,001). After 6 months end-diastolic volume (EDV) was higher in group 2 (128,1+/-46,1 ml vs. 110,2+/-49,7 ml, p<0,008). CONCLUSIONS: ST-resolution after successful PTCA is a simple and effective marker of myocardial reperfusion after recanalization which correlates with angiographic markers of tissue reperfusion. Early ST-segment resolution is connected with better early and late LV function. Patients without early ST-segment elevation resolution have a higher risk of LV remodelling.

Aged↗

PubMed2005

[Preoperative factors for postoperative resolution of metamorphopsia in idiopathic macular hole surgery].

PURPOSE: To elucidate factors for resolution of metamorphopsia after successful surgery for idiopathic macular hole. PATIENTS AND METHODS: A series of 15 cases of 15 patients with successful surgery for idiopathic macular hole were evaluated for signs of metamorphopsia before and one year after surgery. Preoperative and postoperative assessments included testing of metamorphopsia using M-CHART and optical coherence tomography. The postoperative state of the metamorphopsia was judged to have resolved when the test score was 0.2 or less and to be residual when it was more than 0.2. Classification of preoperative factors in two groups of patients included evaluation of metamorphopsia score, visual acuity, optical coherence tomography findings, and clinical stage of macular hole. RESULTS: Six of 15 eyes (40%) showed postoperative resolution of metamorphopsia. There was no significant correlation of postoperative metamorphopsia score with preoperative score or preoperative visual acuity. Eyes with postoperative resolution of metamorphopsia had a macular hole with a significantly smaller diameter and a significantly thinner retina surrounding the hole. Two eyes with clinical stage 4 macular hole had residual metamorphopsia after surgery. CONCLUSIONS: The diameter of a macular hole and the thickness of the retina surrounding a macular hole are significant preoperative factors for postoperative resolution of metamorphopsia after idiopathic macular hole surgery.

Aged↗

PubMed2005

[Resolution of clenbuterol hydrochloride enantiomers by thin-layer chromatography on silica gel impregnated with beta-cyclodextrin].

The resolution of clenbuterol hydrochloride enantiomers was achieved by thin-layer chromatography on silica gel GF254 plates impregnated w ith beta-cyclodextrin. The effect of stereoselective auxiliary (acetonitrile and alcohol) was investigated. Resolution of clenbuterol hydrochloride enantiomers could be attained by using alcohols of butanol, 2-butanol or tert-butanol together with acetonitrile as developing solvent. The optimal conditions of resolution were determined as follows: a plate prepared with 15.00 g silica gel GF254 impregnated with 1.00 g beta-cyclodextrin, acetonitrile-2-butanol (20:80, v/v) as developing solvent and developed at room temperature. Under these conditions, Rf of the two isomers of clenbuterol hydrochloride enantiomers were 0.34 and 0.72 respectively. The resolution was 4.09 with baseline separation and the spots in chromatogram were almost of the same size.

Acetonitriles↗

PubMed2006

Performance characteristics of a new 3-dimensional continuous-emission and spiral-transmission high-sensitivity and high-resolution PET camera evaluated with the NEMA NU 2-2001 standard.

UNLABELLED: The SET-3000 G/X (clinical tomograph with high resolution and a large axial field of view) is a 3-dimensional (3D) (only) dedicated PET camera with germanium oxyorthosilicate (GSO) and bismuth germanate (BGO) scintillators. The main characteristic of the SET-3000 G/X PET scanner is 3D continuous-emission and spiral-transmission (CEST) scanning, yielding a reduction in whole-body scan time. We evaluated the physical performance of the SET-3000 G/X PET scanner with the National Electrical Manufacturers Association (NEMA) NU 2-2001 standard. METHODS: A GSO 3D emission scanner is combined with a BGO transmission scanner separated axially by a lead shield. In the GSO scanner, small and thick scintillators (2.45 x 5.1 x 30 mm(3)) are arranged in small blocks (23.1 x 52 mm) to achieve high resolution and a high counting rate. The detector ring has a large solid angle with a diameter of 664 mm and an axial coverage of 260 mm (50 rings). The transmission scanner consists of BGO block detectors with a diameter of 798 mm and an axial width of 23.1 mm and is equipped with a rotating (137)Cs point source of 740 MBq and a tungsten collimator. The low- and high-energy thresholds are set to 400 and 700 keV, respectively, in the emission system. The coincidence time window is set to 6 ns. In CEST acquisition, the patient couch moves continuously through the emission and transmission scanners in a 1-way motion. Emission coincidence data are acquired in the histogram mode with on-the-fly Fourier rebinning, and transmission single data are acquired with emission contamination correction. RESULTS: With the NEMA NU 2-2001 standard, the main performance results were as follows: the average (radial and tangential) transverse and axial spatial resolutions (full width at half maximum) at 1 cm and at 10 cm off axis were 3.49 and 5.04 mm and 4.48 and 5.40 mm, respectively; the average sensitivity for the 2 radial positions (0 and 10 cm) was 20.71 cps/kBq; the scatter fraction was 50%; the peak noise equivalent count rate was 62.3 kcps at 9.8 kBq/mL; and the peak random rate was 542.1 kcps at 37.6 kBq/mL. CONCLUSION: The new integrated SET-3000 G/X PET scanner has good overall performance, including high resolution and sensitivity, and has the potential of reducing whole-body acquisition time to less than 10 min while improving small-lesion detectability with a low radiation dose.

Equipment Design↗

PubMed2006

In vivo high-resolution MR imaging of neuropathologic changes in the injured rat spinal cord.

BACKGROUND AND PURPOSE: MR imaging is the most comprehensive noninvasive means to assess structural changes in injured central nervous system (CNS) tissue in humans over time. The few published in vivo MR imaging studies of spinal cord injury in rodent models by using field strengths < or = 7T suffer from low spatial resolution, flow, and motion artifacts. The aim of this study was to assess the capacity of a 17.6T imaging system to detect pathologic changes occurring in a rat spinal cord contusion injury model ex vivo and in vivo. METHODS: Seven adult female Fischer 344 rats received contusion injuries at thoracic level T10, which caused severe and reproducible lesions of the injured spinal cord parenchyma. Two to 58 days postinjury, high-resolution MR imaging was performed ex vivo (2) or in vivo in anesthetized rats (5 spinal cord injured + one intact control animal) by using 2D multisection spin- and gradient-echo imaging sequences, respectively, combined with electrocardiogram triggering and respiratory gating. RESULTS: The acquired images provided excellent resolution and gray/white matter differentiation without significant artifacts. Signal intensity changes, which were detected with ex vivo and in vivo MR imaging following spinal cord injury, could be correlated with histologically defined structural changes such as edema, fibroglial scar, and hemorrhage. CONCLUSIONS: These results demonstrate that MR imaging at 17.6T allows high-resolution structural analysis of spinal cord pathology after injury.

Animals↗

PubMed2006

[Correlative analysis between HLA high resolution typing and GVHD in 48 cases received unrelated umbilical cord blood transplantation].

Unrelated umbilical cord blood units for 54 cases in 21 transplant centers were provided by Guangzhou Cord Blood Bank in China from 1998 to 2003. This study was aimed to identify HLA-DRB1 alleles by means of PCR sequencing based typing methods (SBT) and to analyze the correlation between HLA-DRB1 alleles and GVHD in unrelated umbilical cord blood transplantation (UCBT). 48 out of 54 patients received UCBT were followed up. DNA were extracted from cryopreservation blood of recipients/donors with UCBT, HLA-DRB1 alleles typing were done by SBT. Compared with low resolution results of HLA-DRB1 alleles, high resolution results were analyzed to see any correlation between HLA-DRB1 alleles and GVHD. by double-blind statistically analysis of HLA-DRB1 high resolution in 48 donor/recipient typings in UCBT. The results showed that the incidence of GVHD (25%) in patients who has HLA-DRB1 alleles matched with donors significantly lower (65.6%) than that in the patients with HLA-DRB1 alleles mismatched (P = 0.008). It is concluded that HLA-DRB1 by high resolution typing method is important in clinical application in UCBT.

Alleles↗

PubMed2006

Anatomical constraints on source models for high-resolution EEG and MEG derived from MRI.

Electroencephalography (EEG) remains the primary tool for measuring changes in dynamic brain function due to disease state with the millisecond temporal resolution of neuronal activity. In recent decades EEG has been supplanted by CT and MRI for the localization of tumors and lesions in the brain. In contrast to the excellent temporal resolution of EEG, the spatial information in EEG is limited by the volume conduction of currents through the tissues of the head. We have extracted source models (position and orientation) from MRI scans to investigate the theoretical relationship between brain sources and EEG recorded on the scalp. Although detailed information about the boundaries between different tissues can also be obtained from MRI, these models are only approximate because of our relatively poor knowledge of the conductivities of the different tissue compartments in living heads. We also compare the resolution of EEG with magnetoecephalography (MEG), which offers the advantage of requiring less detail about volume conduction in the head. The brain's magnetic field depends only on the position of sources in the brain and the position and orientation of the sensors. We demonstrate that EEG and MEG space average neural activity over comparably large volumes of the brain; however, they are preferentially sensitive to sources of different orientation suggesting a complementary role for EEG and MEG. High-resolution EEG methods potentially yield much better localization of source activity in superficial brain areas. These methods do not make any assumptions about the sources, and can be easily co-registered with the brain surface derived from MRI. While there is much information to be gained by using anatomical MRI to develop models of the generators of EEG/MEG, functional neuroimaging (e.g., fMRI) signals and EEG/MEG signals are not easily related.

Algorithms↗

PubMed1991

Does PEEP facilitate the resolution of extravascular lung water after experimental hydrostatic pulmonary oedema?

The effect of mechanical ventilation with positive end-expiratory pressure on the resolution of hydrostatic pulmonary oedema created by temporary left atrial balloon inflation was studied in mechanically ventilated dogs. Immediately after the hydrostatic process was terminated, by deflating the left atrial balloon, the animals were ventilated for 4 h with zero end-expiratory pressure (ZEEP, n = 6) or with a positive end-expiratory pressure (PEEP, n = 6) of 1.0 kPa (10 cmH2O). Gas exchange and extravascular lung water content (EVLW) with the double indicator dilution technique (dye/cold) were studied and gravimetric determination of lung water was made postmortem. EVLW decreased from 31.6 +/- 7.3 mean +/- SD ml.kg.1 during maximal oedema to 14.5 +/- 2.1 ml.kg.1 (p less than 0.001) 4 h after deflation of the left atrial balloon in dogs ventilated with ZEEP. The corresponding values in dogs ventilated with PEEP were a reduction in EVLW from 28.0 +/- 4.1 to 20.7 +/- 4.0 ml.kg.1 (p less than 0.01) (mean decrease 7.3 +/- 4.0 ml.kg.1). EVLW was significantly higher after 4 h on PEEP than after ZEEP (p less than 0.01). Gravimetric values at the end of the experiment were 12.4 +/- 2.8 ml.kg.1 (ZEEP) and 14.7 +/- 4.5 ml.kg.1 (PEEP) (NS). Oxygenation improved in both groups during the resolution of oedema with a more evident and early effect in the PEEP group. It is concluded that mechanical ventilation with PEEP of 1.0 kPa (10 cmH2O) in the resolution phase after experimental hydrostatic oedema improves oxygenation but retards the resolution of oedema.

Animals↗

PubMed1991

High-pass resolution perimetry in optic neuritis.

The topography of visual field defects resulting from optic neuritis as measured by spatial resolution perimetry is not known. Using high-pass resolution perimetry, the number and severity of visual field defects in the central visual field was determined in 18 patients with resolved optic neuritis and 18 age-matched controls. Comparisons were made between three groups of eyes: (1) the involved eyes of the patients, (2) the uninvolved eyes of the patients, and (3) the eyes of the controls. Concentric zone analysis showed the involved eyes to have depression of the visual field in all zones with slightly more loss centrally. The "uninvolved" eyes showed a mild equal depression in all zones. Spatial resolution acuity measurements (which correlate directly with the spatial separation of retinal ganglion cell receptive field centers) indicated that the percentage of functioning retinocortical channels for normal eyes, uninvolved eyes, and involved eyes were 112%, 94%, and 58% of the reference normal values, respectively. These differences were all statistically significant. Resolution perimetry of the central visual field of eyes with resolved optic neuritis involves the cecocentral and Bjerrum areas. The loss was often patchy and a combination of cecocentral and arcuate defects. There was also a mild generalized depression of the uninvolved eye.

Humans↗

PubMed1991

[Evaluation of pulmonary emphysema with high resolution computed tomography and the effect of smoking].

Cigarette smoking is thought to play an important part in the development of pulmonary emphysema. The authors previously reported on the correlation of high resolution computed tomography (CT) with the pathology grade of emphysema and the destructive index of lung specimens from 42 patients undergoing thoracotomy for a solitary pulmonary nodule. High resolution CT was effective to identify the presence and grade of mild emphysema. The mean per cent predicted FEV1 was 97 per cent. There were 28 smokers and 14 nonsmokers. In this report, the correlation of smoking history with pathology score and high resolution CT was analyzed. There was significant correlation among these indices. These results further support the relationship between smoking and pulmonary emphysema. High resolution CT scan may help in the understanding of the role of cigarette smoking in the development of early pulmonary emphysema.

Adult↗