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PubMed2004

Agreement between the clinical Oxfordshire Community Stroke Project classification and CT findings in Poland.

The Oxfordshire Community Stroke Project (OCSP) classification provides a simple means of classifying the clinical syndromes associated with acute stroke. The validity of the classification can depend on many factors. Accuracy and time of the clinical and radiological examination are very important. It was used in the International Stroke Trial (IST). The study was conducted in 467 hospitals in 34 countries. Our aim was to assess how well the OCSP classification could predict infarct site and size on computed tomography (CT) scan when performed in a trial within 48 h after the onset of stroke and the clinical assessment was carried out by different doctors in different hospitals. We examined data on the patients randomized in the IST by the seven participating hospitals in Poland. Patients admitted to the hospital were examined by the doctor on duty. Eight aspects of the neurological deficit present just before randomization were recorded. The computer system in the randomization centre employed a validated algorithm to assign the patient to one of the four infarct syndromes: lacunar syndrome (LACS), partial anterior circulation syndrome (PACS), total anterior circulation syndrome (TACS) and posterior circulation syndrome (POCS). We assessed the localization and extent of the recent infarction on available CT scans and correlated these with the computer-assigned OCSP category. CT scans were available for 558/759 (74%) of the patients randomized in Poland. In 458 (82%) of cases, CT was carried out in the first 24 h after the onset of stroke. In 444 (80%) scans, a recent infarct was visible. These radiological lesions were appropriate to the clinical classification in 56% of patients with TACS, 73% with PACS, 61% with LACS and 59% with POCS. In Polish centres in IST, amongst the patients with infarction visible on CT, the OCSP subtype predicted the size and site of the infarct in about two-thirds of cases. These data suggest that, provided its limitations are taken into account, the classification can be usefully applied in multicentre clinical trials (or epidemiological studies) and to aspects of the routine clinical care of patients with acute stroke.

Aged↗

PubMed2006

Quantum events of biophoton emission associated with complementary and alternative medicine therapies: a descriptive pilot study.

INTRODUCTION: Biophoton emission (BPE) is a quantum event characterized by a relatively stable but ultralow- rate emission of visible photons from living organisms. It has been associated with high energy processes such as: cell metabolism, growth, phagocytosis, neural activity, and oxidative stress. BPE has also been suggested to reflect the organism's global state of health as well as the response to stimulation including therapeutic interventions. If BPE changes occur as a result of various complementary and alternative medical interventions, this could prove useful to monitor both the patient's response to a specific treatment and global changes in their health status. This descriptive study attempts to identify BPE changes associated with three different chiropractic techniques that use different energetic approaches: mechanical, gravitational, and bioenergetic. MATERIALS AND METHODS: The BPE was measured at the neck and/or the lower back of 3 asymptomatic adult male volunteers. The measurements were made before and after different chiropractic interventions. The treatment techniques included a high velocity joint manipulation with the aid of a drop table, Sacro-Occipital Technique, and Bio-Energetic Synchronization Technique. Enough time was allotted for measurements in order to differentiate between natural fluctuation of the BPE and the changes induced by the interventions. RESULTS: All techniques induced small (up to 20%) but statistically significant changes (p < 0.05 in one case, p < 0.001 in the other two) in the BPE. Each technique demonstrated a different pattern of BPE change that may be specific to the technique. CONCLUSION: The intensity of BPE is a noninvasive indicator of the health of the human body and is significantly altered in different ways by chiropractic interventions. Future research is necessary to explore more features of BPE and its utility as an indicator of health, as well as the theoretical and clinical significance of these findings.

Adult↗

PubMed1984

Danazol treatment of severely symptomatic fibrocystic breast disease and long-term follow-up--the Hjørring project.

The purpose of the investigation was to study various aspects of danazol treatment in patients with fibrocystic breast disease and pronounced mastodynia. To qualify for inclusion, the patients in this study had to have a mammographically confirmed prominent glandular structure and/or severe cystic breast disease, associated with pronounced cyclical mastodynia lasting at least one week per menstrual cycle for more than 6 months. They also had to be premenopausal and not undergoing hormonal therapy. Of 109 patients with a mean age of 40 +/- 6.2 (SD) years, who completed 6 months' treatment with danazol, 65% had a pre-treatment history of more than 5 years. According to detailed mammographic characterization, only 18% of the patients had no visible cysts. Of the 82% with visible cysts, half presented with both small (less than 1 cm) and large cysts. The patients were treated in two consecutive groups, 55 patients receiving 400 mg a day and 54 patients 200 mg a day. The therapeutic response was similar following both dosages. Mastodynia responded rapidly and total elimination was noted in about 90% of cases. A marked decrease in prominence of palpable structure was observed in virtually all patients. Mammographically, a decrease in the amount of glandular tissue was observed. These changes during treatment were statistically highly significant (p less than 0.001), irrespective of dose or category of patient. Non-cystic nodularities gradually decreased in 85% and resolved completely in 58% of the cases, but the degree of resolution in the groups of patients with no or only small (less than 1 cm) visible cysts was significantly greater (p less than 0.02 or less) than in the group which also had large cysts and which included the most severe and intractable cases. The mammographical visualization of cysts, ductal system, and fibrous tissue increased initially due to the marked regression of obscuring glandular tissue. Thereafter, a decrease in the number and spread of small cysts was observed in a significant proportion of patients and in some cases a reduction in duct diameter could be demonstrated by means of galactography. Nipple discharge also decreased. The extent of fibrosis appeared to be unaffected by therapy. In the 46 patients with large cysts and, in most cases, a documented history of repeated cyst formation, danazol treatment was found to arrest the development of new cysts and to prevent recurrence for a considerable time thereafter.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed2003

Inhibition of subliminally primed responses is mediated by the caudate and thalamus: evidence from functional MRI and Huntington's disease.

Masked prime tasks have shown that sensory information that has not been consciously perceived can nevertheless trigger the preactivation of a motor response. Automatic inhibitory control processes prevent such response tendencies from interfering with behaviour. The present study investigated the possibility that these inhibitory control processes are mediated by a cortico-striatal-pallidal-thalamic pathway by using a masked prime task with Huntington's disease patients (Experiment 1) and with healthy volunteers in a functional MRI (fMRI) study (Experiment 2). In the masked prime task, clearly visible left- or right-pointing target arrows are preceded by briefly presented and subsequently masked prime arrows. Participants respond quickly with a left or right key-press to each target. Trials are either compatible (prime and target pointing in the same direction) or incompatible (prime and target pointing in different directions). Prior behavioural and electrophysiological results show that automatic inhibition of the initially primed response tendency is reflected in a 'negative compatibility effect' (faster reaction times for incompatible trials than for compatible trials), and is shown to consist of three distinct processes (prime activation, response inhibition and response conflict) occurring within 300 ms. Experiment 1 tested the hypothesis that lesions of the striatum would interrupt automatic inhibitory control by studying early-stage Huntington's disease patients. Findings supported the hypothesis: there was a bimodal distribution for patients, with one-third (choreic) showing disinhibition, manifested as an absent negative compatibility effect, and two-thirds (non-choreic) showing excessive inhibition, manifested as a significantly greater negative compatibility effect than that in controls. Experiment 2 used fMRI and a region of interest (ROI) template-based method to further test the hypothesis that structures of the striatal-pallidal-thalamic pathway mediate one or more of the processes of automatic inhibitory control. Neither prime activation nor response conflict significantly engaged any ROIs, but the response inhibition process led to significant modulation of both the caudate and thalamus. Taken together, these experiments indicate a causal role for the caudate nucleus and thalamus in automatic inhibitory motor control, and the results are consistent with performance of the task requiring both direct and indirect striatal-pallidal-thalamic pathways. The finding that Huntington's disease patients with greater chorea were disinhibited is consistent with the theory that chorea arises from selective degeneration of striatal projections to the lateral globus pallidus, while the exaggerated inhibitory effect for patients with little or no chorea may be due to additional degeneration of projections to the medial globus pallidus.

Adult↗

PubMed1989

[Radiological assessment of pulmonary function by computed radiography with imaging plates].

The usefulness of computed radiography with imaging plates (CR) for radiological assessment of pulmonary function was studied. Visibility of intrathoracic structures on CR images was compared with that on screen-film images. Intrathoracic structures included right intermediate arterial trunk, midzonal vessels, peripheral zonal vessels, the trachea at the level of the aortic arch, and lateral margin of the spine on posteroanterior radiographs. On lateral radiographs, the pulmonary apex, upper border of the aortic arch, anterior border of the heart, anterior margin of the ascending aorta, and trachea were included. Forty-six posteroanterior and 40 lateral radiographs taken by CR and screen-film radiography were reviewed. CR was often superior in identifying intrathoracic structures. Marked superiority of CR to screen-film radiography in visualizing intrathoracic structures was found in 48% of peripheral zonal vessels, 63% of tracheas on posteroanterior images, 46% of lateral margins of the spine, and 60% of pulmonary apexes. The superiority of CR is due to the wide dynamic range of imaging plates and image-processing procedures. CR will make it easier to identify multiple intrathoracic structures for radiographic measurements. In a second experiment chest radiographs were taken in both deep inspiration and expiration phase with one-shot dual-energy subtraction technique using the CR system in five patients with chronic pulmonary emphysema showing abnormal pulmonary function and 5 patients without any airway obstruction diseases. Original CR plain chest images and bone-subtracted chest images were displayed on a CRT (TDF-500AS, Toshiba Medical, Tokyo) and X-ray densitometry was attempted utilizing digital values.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

PubMed1996

Coronary angiography by electron beam tomography.

Electron Beam Tomography (EBT), a non-invasive imaging method with very high spatial and temporal resolution, is well suited for cardiac imaging. We established a protocol for the visualization of the coronary arteries by EBT and have so far evaluated the method in 88 patients. EBT imaging was performed using an Evolution scanner with a matrix of 512 x 512, a field of view of 15 cm and a slice thickness of 3 mm. After venous injection of contrast agent, 40 axial cross-sections of the heart were obtained triggered to the ECG at 80% of the R-R interval in inspiratory breathhold. With a lower threshold of 80 HU, 3D reconstructions of the heart and coronary arteries were rendered using shaded-surface display and maximum-intensity projection techniques. In all patients, the coronary arteries and, if present, aorto-coronary bypass grafts, were evaluated as to their visibility and presence or absence of haemodynamically relevant stenoses. All results were compared to the X-ray angiograms obtained by selective catheterization in a blinded manner. In 90% of cases, image quality was sufficient for evaluation. In 10% of the investigations, the EBT images could not be evaluated, mainly due to respiration artifacts. While the left anterior descending coronary artery was represented in very good image quality, the right coronary artery and left circumflex coronary artery showed decreased image quality due to motion artifacts and close correlation to venous structures such as the coronary sinus and atrial appendages. In a subgroup of 30 patients in which EBT results were compared to quantitative coronary angiography, the correlation of the vessel diameter in EBT and quantitative angiography was 0.82. Twelve out of 14 high-grade stenoses and 5/5 occlusions of the left anterior descending coronary artery as well as 3/4 highgrade stenoses and 1/2 occlusions of the right coronary artery and 2/4 high-grade stenoses of the left circumflex coronary artery were correctly identified. Nine patients were reinvestigated by EBT after successful angioplasty of high-grade coronary artery stenoses. The increase in vessel diameter could be documented in all cases. Twelve patients had a total of 28 aorto-coronary bypass grafts. Except for one mammarian artery graft which could not be evaluated due to small vessel lumen and clip artifacts, graft patency (21 cases) or occlusion (6 cases) was correctly diagnosed by EBT. EBT is a non-invasive method which permits the visualization of the coronary arteries. Stenoses of coronary artery bypass grafts and of the left anterior descending coronary artery can be reliably diagnosed, while reduced image quality, mainly due to faster vessel motion, impairs the results obtained for the right and left circumflex coronary artery.

Adult↗

PubMed2005

Results of a pilot study of multispectral digital colposcopy for the in vivo detection of cervical intraepithelial neoplasia.

OBJECTIVE: Fluorescence spectroscopy is a promising technology for the detection of cervical squamous intraepithelial precancers and cancers. To date, many investigators have focused on point spectroscopy as an adjunct to diagnostic colposcopy. A device that visualizes the whole field of the cervix is needed for screening. To that end, we have developed a multispectral digital colposcope that works through the colposcope to image with white light, UV excitation at 345 nm, and blue light at 440 nm excitation. Here, we report the pilot study that precedes a Phase I trial. METHODS: The MDC system is composed of a light source, a colposcope, and a video rate color CCD camera with a frame grabber and takes approximately less than 1 min to make images of the cervix. Patients were measured at baseline and after acetic acid placement with white light, 345 nm excitation, and 440 nm excitation from the xenon arc lamp. The white light is in the visible spectrum, 345 nm excitation is in the UV spectrum and is not visible, and 440 nm excitation is blue light in the visible spectrum. White light generates a pink image of the cervix. 345 nm excitation, the UV light, excites fluorophores to emit a blue image. 440 nm excitation, the blue light, excites fluorophores to emit a green image. The patients underwent a loop excision procedure and the histopathology was inked and cut into 12 sections by the study pathologists. The histopathologic slides were scanned and the images were then reconstructed into maps. A diagnostic algorithm was calculated. The data were preprocessed, transformed, and analyzed by the K-means clustering method. Disease maps were generated using the algorithm and classifier and compared to white light colposcopy and the blue and green images obtained at 345 and 440 nm. RESULTS: Forty-six patients were measured at four clinical sites. Images were made of the cervix with white light, 345 nm excitation, and 440 nm excitation and are presented in the figures. As the study went on, images improved with improvements in the instrument. The white light and fluorescence images are presented with crudely constructed histopathologic maps and algorithmic maps. At 345 nm excitation, the UV light, histologically confirmed CIN appears darker blue; while at 440 nm excitation, the blue light, histologically confirmed CIN appears lighter green. CONCLUSIONS: This pilot study shows that MDC images can be matched to both histopathologic and algorithmic maps. The device and the algorithm are evolving but show promise. A Phase I trial is planned.

Adult↗

PubMed2004

Computerized nipple identification for multiple image analysis in computer-aided diagnosis.

Correlation of information from multiple-view mammograms (e.g., MLO and CC views, bilateral views, or current and prior mammograms) can improve the performance of breast cancer diagnosis by radiologists or by computer. The nipple is a reliable and stable landmark on mammograms for the registration of multiple mammograms. However, accurate identification of nipple location on mammograms is challenging because of the variations in image quality and in the nipple projections, resulting in some nipples being nearly invisible on the mammograms. In this study, we developed a computerized method to automatically identify the nipple location on digitized mammograms. First, the breast boundary was obtained using a gradient-based boundary tracking algorithm, and then the gray level profiles along the inside and outside of the boundary were identified. A geometric convergence analysis was used to limit the nipple search to a region of the breast boundary. A two-stage nipple detection method was developed to identify the nipple location using the gray level information around the nipple, the geometric characteristics of nipple shapes, and the texture features of glandular tissue or ducts which converge toward the nipple. At the first stage, a rule-based method was designed to identify the nipple location by detecting significant changes of intensity along the gray level profiles inside and outside the breast boundary and the changes in the boundary direction. At the second stage, a texture orientation-field analysis was developed to estimate the nipple location based on the convergence of the texture pattern of glandular tissue or ducts towards the nipple. The nipple location was finally determined from the detected nipple candidates by a rule-based confidence analysis. In this study, 377 and 367 randomly selected digitized mammograms were used for training and testing the nipple detection algorithm, respectively. Two experienced radiologists identified the nipple locations which were used as the gold standard. In the training data set, 301 nipples were positively identified and were referred to as visible nipples. Seventy six nipples could not be positively identified and were referred to as invisible nipples. The radiologists provided their estimation of the nipple locations in the latter group for comparison with the computer estimates. The computerized method could detect 89.37% (269/301) of the visible nipples and 69.74% (53/76) of the invisible nipples within 1 cm of the gold standard. In the test data set, 298 and 69 of the nipples were classified as visible and invisible, respectively. 92.28% (275/298) of the visible nipples and 53.62% (37/69) of the invisible nipples were identified within 1 cm of the gold standard. The results demonstrate that the nipple locations on digitized mammograms can be accurately detected if they are visible and can be reasonably estimated if they are invisible. Automated nipple detection will be an important step towards multiple image analysis for CAD.

Algorithms↗

PubMed2004

Effect of multi-adhesive layering on retention of extraoral maxillofacial silicone prostheses in vivo.

STATEMENT OF PROBLEM: Loss of retention of maxillofacial prostheses often makes the margin visible or the prosthesis dislodge. Using several medical adhesives in combination may improve retention. PURPOSE: The purpose of this study was to investigate the effect of single- and multi-adhesive layering of 2 adhesives on the retention of maxillofacial silicone elastomer strips adhered to the skin of human forearms using a peel test. MATERIAL AND METHODS: Power analysis from a previous study and a pilot trial specified at least 20 subjects. Eight Silastic Adhesive A/MDX4-4210 silicone rubber strips (N=240) were applied in a predetermined random order to the left and right ventral forearms of 30 IRB-approved human subjects. Skin-Prep Protective Dressing was applied. Secure 2 Medical Adhesive (SMA) and Epithane-3 (E3) adhesive were used alone or as SMA/E3 or E3/SMA sandwiches (from skin to prosthesis) to adhere strips. Strips were peeled 6 hours later in a universal testing machine at 10 cm/min and data reported in N/m. Paired t tests were used to evaluate left and right arm differences. A Friedman test for nonparametric correlated data with within-subject design was performed, determining differences between both adhesives singly and in combination (alpha=.05). RESULTS: Tests of left-right differences were insignificant ( P =0.43), so the data from both arms were combined. Many strips with E3 did not adhere before testing and were counted as 0 adhesion. Median peel strengths (and 25th and 75th percentiles) in N/m were: SMA = 76.1 (47.1-107), E3 = 6.75 (0.0-25.9), SMA/E3 = 107 (78.0-132), and E3/SMA= 19.6 (6.99-42.4). All 4 variables were significantly different ( P <.0005). CONCLUSION: The multi-adhesive combination of SMA/E3 had the highest adhesion, followed, in order, by SMA alone, E3/ SMA, and E3 alone. Both E3 groups left a difficult-to-remove residue on the skin. SMA/E3 left a halo-like residue on the skin at the periphery of the strips from the E3 leaking around the SMA. SMA remained adherent to the prosthetic material.

Adhesives↗

PubMed2003

Impairments and Hansen's disease control in Rondônia state, Amazon region of Brazil.

This retrospective study of impairments in a decentralized and integrated, routine Hansen's disease (HD) programme was done on a cohort of all new patients detected in Rondônia state from 1996 to 1999. It shows that the dynamics of impairments during treatment in Rondônia are similar to what has been published in other recent studies from Africa and Asia. Data about impairments at detection and at release from treatment (cure), the prescription of steroids, and epidemiological information are provided. Of the original 5350 new patients, 4230 patients (80%) completed multidrug therapy (MDT) and had complete data about their impairment status. At the start of treatment, 9% of the paucibacillary (PB) and 26% of the multibacillary (MB) patients had WHO grade 1 impairment. Three percent of the PB and 11% of the MB patients had visible deformities (WHO grade 2 impairment). Of the patients without impairments (grade 0) at the start of treatment, 5% of the PB and 20% of the MB patients developed impairments during treatment. Of the PB patients with a WHO impairment grade 1 at start of treatment, 34% improved and 6% got worse. Of the MB patients 34% improved and 12% became worse. In a separate study of patients from the 1997 intake, 17% of the PB and 58% of the MB patients were treated at least once with a course of steroids or thalidomide during MDT treatment. It is noted in the literature that the percentage of persons with recent nerve function impairment (NFI), nerve pain or tenderness and/or reaction reactions differs between projects. This may reflect real differences or may be caused by differences in routine monitoring and/or criteria and methods of treatment. The use of the WHO maximum score, particularly for the patients with grade 2, is not as sensitive to change as utilizing the summary of Eye, Hand and Foot (EHF) scores. If overall impairment figures are given, the proportions of MB patients may define the differences between projects, therefore it is important to analysis and present the results of PB and MB patients separately. The most simple (outcome) indicator to estimate the effectiveness of patient management would be the proportions of patients with impairment grade 0 at start of treatment who develop either grade 1 or 2 impairments during treatment. An additional (outcome) indicator could be the proportion of patients with impairment grade 1 at start of treatment who develop grade 2 impairments during treatment. Currently, no operational targets or acceptable level of performance for patient management have been set. This would be important to enable programme managers to determine if adequate patient education, treatment and follow up have been provided after the disease detection to prevent and/or minimize problems associated with the disease. The available evidence strongly suggests that reactions and impairments related to HD will continue to occur in large numbers, requiring the development of adequate infrastructures and sustainable services to detect and to manage problems associated with HD during and after MDT treatment.

Adolescent↗

PubMed2000

[Normative needs for care of schizophrenics: a useful concept for community psychiatric planning?].

One step in a public health research project focuses on the analysis of the individual (expert-based) normative needs for mental health care of chronic schizophrenic patients (n = 115) in the Dresden Region during the first year post hospital release and the extent to which this can be met by the current established level of complementary care. It is an exemplary contribution to the evaluation of community psychiatry as restructured in the Free State of Saxony following German reunification. The results of the study can be condensed to the following interpreting essential statements. Schizophrenics' normative needs for care are not a statistical issue. The single case analysis corroborates a high rate of relevant fluctuations, above all within the clinical sector (e.g. concerning "dyskinesias and other side effects"), that pose a particular challenge to the flexibility of a system of community psychiatry. This includes that the consequence for the practice of care implies then that when diagnosing course, attention must be paid to shifts in the content of the needs for mental health care (e.g. increasing importance of factors, which contain impairments of basic social competences) in order to orient to them any health care measures already initiated.--With the aid of the used research instrument (Needs for Care Assessment) deficits in meeting the needs for care can be identified. In the Dresden Region considerable deficits persist apparently in the subsections recreational activities and occupational and communication skills, which can be ascribed to the lack of appropriate institutions of care in the area.--The normative needs for care of schizophrenic patients cannot be determined simply on the basis of a few, quickly identifiable markers. Rather it demands individualized analysis incorporating variables pertaining to psychopathology, subjective coping, social competence and the course of the disorder. The development of the needs for care over the period of one year can apparently be predicted by trends in the social sector that are already visible within the first months. With regard to aspects of care planning this finding illustrates the limited ability of cross-section surveys to make definitive statements, as well as the predominance of social disabilities over the entire spectrum of the normative needs for psychiatric care.

Adult↗

PubMed2001

Intraocular retinal prosthesis.

PURPOSE: An electronic implant that can bypass the damaged photoreceptors and electrically stimulate the remaining retinal neurons to restore useful vision has been proposed. A number of key questions remain to make this approach feasible. The goal of this thesis is to address the following 2 specific null hypotheses: (1) Stimulus parameters make no difference in the electrically elicited retinal responses. (2) Just as we have millions of photoreceptors, so it will take a device that can generate millions of pixels/light points to create useful vision. METHODS: For electrophysiologic experiments, 2 different setups were used. In the first setup, charge-balanced pulses were delivered to the retinal surface via electrodes inserted through an open sky approach in normal or blind retinal degenerate (rd) mice. In the second setup, the rabbit retina was removed under red light conditions from an enucleated eye and then maintained in a chamber while being superfused with oxygenated, heated Ames media. In both setups, stimulating electrodes and recording electrodes were positioned on the retinal surface to evaluate the effect of varying stimulation parameters on the orthodromic retinal responses (i.e., recording electrode placed between stimulating electrodes and optic nerve head). For psychophysical experiments, visual images were divided into pixels of light that could be projected in a pattern on the retina in up to 8 sighted volunteers. Subjects were asked to perform various tasks ranging from reading and face recognition to various activities of daily living. RESULTS: Electrophysiologic experiments: In a normal mouse, a single cycle of a 1-kHz sine wave was significantly more efficient than a 1-kHz square wave (P < .05), but no such difference was noted in either of the 8- or 16-week-old rd mouse groups (8-week-old, P = .426; 16-week-old, P = .078). Charge threshold was significantly higher in 16-week-old rd mouse versus both 8-week-old rd and normal mouse for every stimulus duration (P < .05). In all groups, short duration pulses (40, 80, and 120 microseconds) were more efficient in terms of total charge (the product of pulse amplitude and pulse duration) than longer (500 and 1,000 microseconds) pulses (P < .05). In all groups, applying a pulse train did not lead to more efficient charge usage (P < .05). Psychophysical experiments: In high-contrast tests, facial recognition rates of over 75% were achieved for all subjects with dot sizes of up to 31.5 minutes of arc when using a 25 x 25 grid with 4.5 arc minute gaps, a 30% dropout rate, and 6 gray levels. Even with a 4 x 4 array of pixels, some subjects were able to accurately describe 2 of the objects. Subjects who were able to read the 4-pixel letter height sentences (on the 6 x 10 and 16 x 16 array) seemed to have a good scanning technique. Scanning at the proper velocity tends to bring out more contrast in the lettering. The reading speed for the 72-point font is a bit slower than for the next smaller font. This may be due to the limited number of letters (3) visible in the window with this large font. CONCLUSIONS: Specific parameters needed to stimulate the retina were identified. Delineating the optimum parameters will decrease the current requirements. Psychophysical tests show that with limited pixels and image processing, useful vision is possible. Both these findings should greatly simplify the engineering of an electronic retinal prosthesis.

Adult↗

PubMedDate not supplied

Evaluation of small pulmonary arteries by 16-slice multidetector computed tomography: Optimum slab thickness in condensing transaxial images converted into maximum intensity projection images.

OBJECTIVE: The purpose of this study was to determine the optimal slab thickness for condensing transaxial images into maximum intensity projection (MIP) images in the evaluation of small pulmonary arteries using 16-slice multidetector-row computed tomography (MDCT). METHODS: Helical computed tomography (CT) scans were obtained from lung apices to bases using 16-slice MDCT [120 kV(peak), 180 mA, beam width of 10 mm, beam pitch of 1.375, and reconstruction thickness of 1.25 mm] in 29 patients suspected of having a pulmonary embolism. Four kinds of image series (1.25-mm thick original transaxial source images and 3 kinds of reconstructed images using the MIP technique with slab thicknesses of 2.5 mm, 5 mm, and 10 mm) were obtained from each patient and forwarded to monitors of a picture archiving and communication system for analysis by 2 independent observers. The observers recorded the name of the segmental (20 total; 10 in each lung) and subsegmental (40 total; 20 in each lung) arteries that were traceable in each image series. Image quality of the 4 image types were graded into 5 scales based on their degree of vascular opacification, the sharpness of the vascular margins of the contrast-enhanced CT angiograms, and the visibility of lung parenchyma (excellent [5] to nondiagnostic [1]) and compared. RESULTS: In both the 1.25-mm thick original transaxial and 2.5-mm thick MIP images, a higher percentage of subsegmental arteries was traceable (91.3% [2119/2320 observations] and 87.2% [2023/2320 observations], respectively; P <0.05) than in the 5-mm and 10-mm thick MIP images (66.4% [1540/2320] and 40.5% [940/2320], respectively). No statistically significant difference was observed between the 1.25-mm thick transaxial and 2.5-mm thick MIP images in this respect. Image quality of 2.5-mm thick MIP images was superior to that of the 5-mm and 10-mm thick MIP images (P < 0.0001). No statistically significant difference was found between the scores of the image quality of the 1.25-mm thick original transaxial images and the 2.5-mm thick MIP images. CONCLUSION: After reducing the image number by one half, 2.5-mm thick MIP images using 16-slice MDCT are found to provide satisfactory images, which are comparable to 1.25-mm thick transaxial images for the analysis of subsegmental pulmonary arteries in patients suspected of pulmonary embolism.

Adult↗

PubMed1986

Zinc protoporphyrin levels in children in Haifa: a pilot study.

Zinc protoporphyrin (ZPP) levels of greater than or equal to 40 micrograms dl-1 were found in blood samples of 32 (12.1%) out of 264 children living in Kiryat Yam, Haifa Bay (a sea-level neighborhood with much vehicular traffic, located 4.5 km from an industrial zone in the bay area), 22 (8.8%) out of 251 children living in Neve Shaanan (located on a mountainside, 3.5 km from an industrial zone and exposed to visible smoke pollution), and 14 (6.5%) out of 214 children from Mt Carmel (Ahuza), which is furthest from industry and where visible signs of pollution are seldom seen. Zinc protoporphyrin levels, low in non-anemic infants, were slightly higher in 1st graders from all three neighborhoods; higher levels were found in both 3rd and 6th graders from Kiryat Yam, but only in 6th graders from Neve Shaanan. The ZPP levels remained unchanged in older, Mt. Carmel children. Zinc protoporphyrin concentrations of greater than or equal to 40 micrograms dl-1 varied inversely with two indices of socio-economic status (parental ethnic origin and father's educational level). Blood lead levels of greater than or equal to 20 micrograms dl of blood were found in eight (13%) out of 62 children with ZPP levels greater than or equal to 40 micrograms dl-1, but in none (0%) of 14 children with ZPP levels greater than or equal to 40 micrograms dl-1. Three (60%) out of five children with ZPP levels greater than or equal to 50 micrograms dl-1 had Pb levels of greater than or equal to 20 micrograms dl-1. In Kiryat Yam, Pb(B) was higher in 31 children with ZPP greater than or equal to 40 micrograms dl-1 compared with 13 with ZPP less than 40 micrograms dl-1. The data on age-associated increases in ZPP in children suggest the possibility of an effect on red blood cell porphyrin metabolism, in some cases from cumulative low level lead exposures, and in others from iron deficiency, especially in poorer socio-economic groups. The findings call for further studies, both in the populations studied here, and elsewhere, to determine the role of lead toxicity and iron deficiency in children of all age groups, and the need for preventive action.

Age Factors↗

PubMed1997

Curative irradiation of limited endobronchial carcinomas with high-dose rate brachytherapy. Results of a pilot study.

OBJECTIVES OF THE STUDY: Pilot study to assess high-dose rate (HDR) brachytherapy as sole treatment for limited endobronchial non-small cell lung carcinomas. INCLUSION CRITERIA: Proximal non-small cell lung cancer in a not previously irradiated area, with a maximal diameter of 1 cm, no visible tumor on CT scan, lack of other treatment options in patients with severe, chronic respiratory failure, surgery, or external radiotherapy for a previous lung cancer. TREATMENT PROTOCOL: Treatment was based on an escalating dose protocol. Patients received three to five fractions of 7 Gy prescribed at 10 mm from the center of the applicator, once a week. RESULTS: Nineteen patients were included in this trial. The first two patients received three fractions of 7 Gy, the four next patients received four fractions, and the 13 remaining patients were treated with five fractions of 7 Gy. Two months after the end of the procedure, tumors in 15 of 18 evaluable patients (83%) were locally controlled with negative results of biopsies. At 1 year, local control was still obtained in 12 of 16 evaluable patients (75%). With a mean follow-up of 28-months, 1-year and 2-year actuarial survival rates were 78% and 58%, respectively, with a 28-month median survival. One patient with local control died from hemoptysis 12 months after treatment. Two patients suffered from severe necrosis of the bronchial wall; one of them died from hemoptysis. CONCLUSIONS: HDR brachytherapy is an effective treatment for small endobronchial tumors. Late toxicity on the bronchial wall is still too high and was attributed mainly to contact between the catheter and the bronchial mucosa. Exclusive HDR brachytherapy should be restricted to carefully selected patients for whom there is no alternative curative treatment. New bronchial applicators and a lower dose per fraction may reduce the incidence and attenuate the severity of late complications.

Actuarial Analysis↗

PubMed1994

Effects of intensive multiple risk factor reduction on coronary atherosclerosis and clinical cardiac events in men and women with coronary artery disease. The Stanford Coronary Risk Intervention Project (SCRIP).

BACKGROUND: Recent clinical trials have shown that modification of plasma lipoprotein concentrations can favorably alter progression of coronary atherosclerosis, but no data exist on the effects of a comprehensive program of risk reduction involving both changes in lifestyle and medications. This study tested the hypothesis that intensive multiple risk factor reduction over 4 years would significantly reduce the rate of progression of atherosclerosis in the coronary arteries of men and women compared with subjects randomly assigned to the usual care of their physician. METHODS AND RESULTS: Three hundred men (n = 259) and women (n = 41) (mean age, 56 +/- 7.4 years) with angiographically defined coronary atherosclerosis were randomly assigned to usual care (n = 155) or multifactor risk reduction (n = 145). Patients assigned to risk reduction were provided individualized programs involving a low-fat and -cholesterol diet, exercise, weight loss, smoking cessation, and medications to favorably alter lipoprotein profiles. Computer-assisted quantitative coronary arteriography was performed at baseline and after 4 years. The main angiographic outcome was the rate of change in the minimal diameter of diseased segments. All subjects underwent medical and risk factor evaluations at baseline and yearly for 4 years, and reasons for all hospitalizations and deaths were documented. Of the 300 subjects randomized, 274 (91.3%) completed a follow-up arteriogram, and 246 (82%) had comparative measurements of segments with visible disease at baseline and follow-up. Intensive risk reduction resulted in highly significant improvements in various risk factors, including low-density lipoprotein cholesterol and apolipoprotein B (both, 22%), high-density lipoprotein cholesterol (+12%), plasma triglycerides (-20%), body weight (-4%), exercise capacity (+20%), and intake of dietary fat (-24%) and cholesterol (-40%) compared with relatively small changes in the usual-care group. No change was observed in lipoprotein(a) in either group. The risk-reduction group showed a rate of narrowing of diseased coronary artery segments that was 47% less than that for subjects in the usual-care group (change in minimal diameter, -0.024 +/- 0.066 mm/y versus -0.045 +/- 0.073 mm/y; P < .02, two-tailed). Three deaths occurred in each group. There were 25 hospitalizations in the risk-reduction group initiated by clinical cardiac events compared with 44 in the usual-care group (rate ratio, 0.61; P = .05; 95% confidence interval, 0.4 to 0.9). CONCLUSIONS: Intensive multifactor risk reduction conducted over 4 years favorably altered the rate of luminal narrowing in coronary arteries of men and women with coronary artery disease and decreased hospitalizations for clinical cardiac events.

California↗

PubMed2003

Detection of in vitro demineralization adjacent to restorations using quantitative light induced fluorescence (QLF).

AIM: Quantitative light-induced fluorescence (QLF) is a technique for the detection, quantification, and longitudinal monitoring of early carious lesions. The technique is non-destructive and can be used in vivo. Using the natural fluorescence of teeth, and the loss of such fluorescence in demineralized enamel, QLF is a repeatable and valid optical caries monitor. Previously used in smooth and occlusal surfaces, the purpose of this pilot study was to determine if QLF could detect, and longitudinally monitor, demineralization adjacent to a range of restorative materials. METHODS: Fifteen previously extracted lower third molars were selected based upon the lack of any visible demineralization. A single burr hole was placed on the buccal surface and the cavity restored with amalgam, composite, compomer, glass ionomer or a temporary filling material. The buccal surface was then coated in an acid resistant nail varnish leaving an exposed area around the restoration and also a similar sized control region. The teeth had QLF images taken at baseline and were then subjected to a demineralizing buffer, further QLF images were subsequently taken at 72 and 144 h. Transverse microradiography was used to confirm the presence of early, subsurface lesions at the completion of the cycle (144 h). QLF images were analyzed by a single blinded examiner and values for change in radiance fluorescence were computed. These values were recorded as loss of radiance fluorescence loss integrated over area of lesion and expressed as DeltaQ. RESULTS: The appearance of each material under QLF and the change in fluorescence is described. Amalgam, glass ionomer and the temporary material all exhibited reduced fluorescence, while composite and compomer showed increased fluorescence, when compared with surrounding enamel. There was no change in fluorescence of the materials when subjected to experimental demineralizing conditions. Readings at 72 and 144 h demonstrated demineralization adjacent to the restorations and at the exposed control. Significant differences were detected between baseline, 72 and 144 h using ANOVA on all restorations with the exception of compomer where significance was noted between baseline and 144 h, p>0.05. CONCLUSIONS: This pilot study has demonstrated the ability for QLF to detect and monitor secondary caries. Analysis techniques should be based upon the subtraction of baseline DeltaQ scores from subsequent images. Further research is required to assess the ability of QLF to detect secondary lesions in vivo.

Analysis of Variance↗

PubMed2004

[Ultrasound evaluation of NO-donor (L-arginine) therapy for intrauterine growth retardation].

UNLABELLED: There are many methods of the growth restriction therapy, but the results are still not satisfactory. Actually, we are conducting a project which main conception is based on the use of the NO donor (L-arginine) in growth retardation therapy. This amino acid is an effective NO donor and has a vasodilating effect on the vessels and anti-aggregation effect on platelets, which plays a great role in improving feto-maternal blood flow. The main aim of this paper is the ultrasound evaluation of the effectiveness of NO-donor (L-arginine) therapy for intrauterine growth retardation based on biometrical measurements (estimated fetal weight) compared with newborns weight estimation. METHODS: The investigated group comprised two groups of pregnant women with ultrasonographically diagnosed intrauterine growth retardation (biometry <10th percentile for the gestation age): --78 patients were treated by L-arginine 3 g daily p.o. in 20 days period. --30 patients not treated (no agreement for therapy) as controls. RESULTS: Ultrasound estimation of fetal weight at the start and at the end of the treatment showed a mean value increase of 642 g (SE 90g) using Shepard method and 648g (SE 94g) using Hadlock method respectively. Comparing not treated group there was assessed a mean value increase of 395 g (SE 77 g) using Shepard method and 404g (SE 82g) using Hadlock method respectively. There is statistical significant difference comparing an estimated fetal weight in both methods: p = 0.008 for Shepard calculation and p = 0.012 for Hadlock calculation. There was analyzed newborn weight also--in a treated group mean value was at 2823 g and in not treated group mean value was at 2495 g. There was no significant difference found but a positive tendency for treated group newborns weight is visible. In the treated group number of the growth retarded newborns was at 29% and in the not treated group was at 73%. There was found a significant difference comparing both newborns groups at p < 0.05. CONCLUSIONS: The ultrasound evaluation of the estimated fetal weight and after-birth weight estimation of the newborns showed an increased dynamic of the fetal development in the L-arginine treated group of pregnant women comparing to the not treated group. The ultrasound evaluation of the estimated fetal weight is a good diagnostic tool for properly monitoring the effectiveness of treatment with L-arginine for growth retarded fetuses.

Arginine↗