Detailed Diagnostic Information Research Articles

From the RSNA refresher courses: imaging evaluation for acute pain in the right upper quadrant.

Acute cholecystitis is the most common cause of acute pain in the right upper quadrant (RUQ), and urgent surgical removal of the gallbladder is the treatment of choice for uncomplicated disease. However, cross-sectional imaging is essential because more than one-third of patients with acute RUQ pain do not have acute cholecystitis. In addition, patients with complications of acute cholecystitis, such as perforation, are often best treated with supportive measures initially and elective cholecystectomy at a later date. Ultrasound (US) is the primary imaging modality for assessment of acute RUQ pain; US is both sensitive and specific in demonstrating gallstones, biliary dilatation, and features that suggest acute inflammatory disease. Occasionally, additional imaging modalities are indicated. Computed tomography is valuable, especially for confirming the extent and nature of the complications of acute cholecystitis. Magnetic resonance cholangiopancreatography is helpful in complicated ductal disease (eg, recurrent pyogenic cholangiohepatitis) when more detailed diagnostic information is required for treatment planning, whereas endoscopic retrograde cholangiopancreatography is used when biliary intervention is required (eg, treatment of choledocholithiasis). Successful imaging with all modalities requires familiarity with both the characteristic and the unusual features of a wide variety of pathologic conditions. In addition, potential pitfalls must be recognized and avoided.

Future prospects in magnetic resonance imaging.

Cardiovascular magnetic resonance (CMR) is widely regarded as capable of providing a cornucopia of detailed diagnostic information. However, of that information, very little is truly unique, and can be obtained by a combination of alternate diagnostic modalities. Given this, it is anticipated that in the short term (1-5 years) CMR will find use primarily as a modality to service patients whose diagnosis is inaccessible to established technologies such as ultrasound and radionuclide imaging. Due to the evolving emphasis on finding new and more efficient approaches to disease detection and prevention, as outlined in a policy-setting speech given by the director of the National Institutes of Health, it is anticipated that the scientific and clinical trial communities will adopt CMR at a more rapid pace due to its inherent dimensional accuracy and comprehensive nature. CMR is particularly well suited to participate in the approaching explosion of nanoparticle technologies, as they are applied to diagnostic and therapeutic approaches. In the longer term (5-10 years), as paradigms of disease detection likely expand beyond evaluation of symptoms and risk factors, the comprehensive nature of information provided by CMR will drive the increase of its use as a primary, first-tier, diagnostic modality. In summary, the use of CMR will become increasingly common, and as understanding of disease processes expand, it will emerge as a diagnostic modality that provides an abundance of unique information.

Handling and pathology reporting of specimens with carcinoma of the urinary bladder, ureter, and renal pelvis.

Pathologists play a pivotal role in the diagnosis and in the report of the pathological features related to prognosis. To meet these endpoints, the following issues must be accomplished: adequate information about the patient history, proper handling of the specimens, identification of the reliable histopathological techniques necessary to reach the more detailed diagnostic information and evaluate the prognostic variables, and a standardized pathological report. Recent efforts to standardize the histopathological evaluation have generated significant confusion among the urological and pathological communities as well. No consensus has been achieved about the optimal pathological grading of urothelial tumors, to date. A proposal for standardization of sampling and reporting of the urothelial tissues achieved within Uropathology follows. The urologists have a great role in assisting pathologists in the proper examination by providing them with clinical information.

A simple and rapid method for identifying the source of spilled oil using an electronic nose: confirmation by gas chromatography with mass spectrometry.

Two types of electronic nose (EN), different in operational principle, were used to identify the source of spilled oil in an accident. The suspected sources considered were petroleum oil reservoirs and pipelines located near the site of the accident. Gas chromatography/mass spectrometry (GC/MS), operated in both EI and CI modes, was employed to confirm the identified source. The advantage of multisensors in spatially resolved sensing for direct multicomponent analysis was explored to minimize tedious sample preparation procedures. Subsequent principal component analysis helped in identifying the source. The advantage of fast separation in temporally resolved sensing was explored to rapidly yield compositional information; the resulting graphical representations helped clarify the source. Traditional GC/MS not only confirms the identified spilled oil source, but also provides detailed diagnostic information such as total petroleum hydrocarbons, polycyclic aromatic hydrocarbons and their C1-C4 alkylated homologues, as well as the n-alkanes, which are essential for follow-up remedial and regulatory actions. The main use of the electronic nose was demonstrated to be as a simple and rapid screening method for identifying a spilled oil source.

Psychometric properties of an index of emotional distress in the U.S. National Comorbidity Survey.

The National Comorbidity Survey (NCS; Kessler et al. 1994) was a nationwide household survey of the U.S. population designed to produce data on the prevalence and correlates of psychiatric disorders. The NCS dataset is now in public-use format and continues to be widely used for ongoing research efforts. The NCS dataset included a set of 14 items that have face validity as a measure of current emotional distress (depression and anxiety) and could serve as a potentially useful continuous measure of psychological distress. However, there have been no published studies on its psychometric properties and this measure has not yet been utilized by researchers using the NCS dataset. This paper provides an evaluation of the psychometric properties of the NCS Distress Index. The NCS Part II public-use dataset (N = 5877) was used. Detailed diagnostic information was collected along with 14 items assessing current psychological distress and measures of Neuroticism and Openness to Experience. The NCS Distress Index was found to be internally consistent (Alpha = 0.92) and a series of principal-components analyses demonstrated that the measure is most accurately conceptualized as a single-factor measure of general distress. The construct validity of the Distress Index was supported by its associations with the measures of Neuroticism and Openness to Experience. A series of comparisons between diagnostic groups also supported the construct validity of the measure. For example, those with disorders characterized by depressed mood and worry scored higher on the Distress Index than those with disorders characterized by fear and hyperarousal. The NCS Distress Index is a psychometrically sound measure of current emotional distress. Future studies utilizing the NCS public-use dataset could potentially benefit from the inclusion of this measure in addition to more commonly investigated categorical variables such as diagnosable disorders.

Diagnosis and management of suspected cases of bioterrorism: a pediatric perspective.

Since October 3, 2001, the Centers for Disease Control and Prevention and other organizations have been investigating potential bioterrorist-related anthrax cases. The pediatrician may be faced with complex issues related to diagnosis and treatment of illnesses caused by intentionally released biological agents. The agents that pose a major potential bioterrorist threat are reviewed by the clinical syndromes they produce: acute respiratory distress with fever, influenza-like illnesses, acute rash with fever, neurologic syndromes, and blistering syndromes. Specific and detailed diagnostic, treatment, and prophylaxis information is provided for anthrax, plague, tularemia, smallpox, botulism, viral hemorrhagic fevers, and other diseases. In cases of suspected bioterrorism, the pediatrician must be able to obtain diagnostic and treatment information efficiently and expeditiously. The system controlling the interaction between public and nonpublic health laboratories in suspected cases of bioterrorism is described. Finally, information regarding emergency contacts and links to educational resources is provided.

Audio acoustic plant condition monitoring of spiral bevel gearbox

Plant condition monitoring (PCM) is widely used by a variety of industries as part of a condition based maintenance programme. This replaces the previous ‘schedule’ based maintenance programme, in which individual components of a machine are replaced at specified intervals. With PCM the condition of the individual components is monitored, and they are only replaced when their performance is deemed unsatisfactory. PCM techniques are often capital and/or labour intensive, and their use limited to critical machines only. The objective of the present research is to develop a system comprised of microphones and accelerometers which is able to screen industrial environments, such as the hot rolling mill at Corus's Port Talbot plant, for machine faults. The system would use the minimum number of transducers to remotely screen the maximum number of machines, but is not required to provide detailed diagnostic information. To date, an omnidirectional microphone has been used successfully to detect badly damaged gear teeth. The method does not require the use of a soundproof enclosure to filter out background noise. A finite element analysis model of the test rig has been created to determine the eigenfrequencies and eigenmodes of the test rig and to improve the understanding of the vibration behaviour of the faults.

New techniques for efficient sliding thin-slab volume visualization.

High-resolution three-dimensional (3-D) volumetric images obtained by today's radiologic imaging scanners are rich in detailed diagnostic information. Despite the many visualization techniques available to assess such images, there remains information that is challenging to uncover, such as the location of small structures (e.g., mediastinal lymph nodes, narrowed-airway regions). Recently, sliding thin-slab (STS) visualization was proposed to improve the visualization of interior structures. These STS techniques sometimes depend on user opacity specifications or extra preprocessing, and other rendering approaches that use the general STS mechanism are conceivable. We introduce two techniques for STS volume visualization. The first, a depth (perspective) rendering process, produces an unobstructed, high-contrast 3-D view of the information within a thin volume of image data. Results are a function of relative planar locations. Thus, rendered views accurately depict the internal properties that were initially captured as position and intensity. The second method produces a gradient-like view of the intensity changes in a thin volume. Results can effectively detect the occurrence and location of dramatic tissue variations, often not visually recognized otherwise. Both STS techniques exploit the concept of temporal coherence to form sequences of consecutive slabs, using information from previously computed slabs. This permits efficient real-time computation on a general-purpose computer. Further, these techniques require no preprocessing, and results are not dependent on user knowledge. Results using 3-D computed tomography chest images show the computational efficiency and visual efficacy of the new STS techniques.

Identifying persons with chronic conditions in a managed care setting: A comparison of methods

PURPOSE: Together, the sophisticated computerized information systems and defined, stable populations within Health Maintenance Organizations (HMOs) can reduce imprecision associated with modeling disease incidence and prevalence. Such data are useful for resource allocation, intervention planning, epidemiological study and surveillance. Identifying all cases of illness within such a defined population is vital to these aims, yet detailed diagnostic information is lacking in many pre-paid plans. In this presentation, diagnostic and prescription data are compared for their ability to assess the treatment prevalence for 28 chronic medical conditions.METHODS: Group Health Cooperative is a mixed model HMO in Western WA state. Automated records for calendar year 1999 were examined for 182,174 commercially insured patients age 20–64. Prescription drug data and International Classification of Disease—9th Clinical Modification codes (ICD-9CM) were used to identify 28 chronic medical conditions among patients. Chi square tests were performed to compare results produced by the two methods.RESULTS: The diagnostic method worked best for conditions with no clear pharmacologic treatment. However, the pharmacy-based method better identified patients with chronic illnesses initially diagnosed prior to 1999, and with disorders for which standard diagnostic codes are inconsistently utilized, such as mental health conditions.CONCLUSIONS: While both diagnostic and pharmacy-based methods perform well in identifying a limited set of conditions, each performs poorly under certain circumstances. A hybrid method utilizing both diagnostic and pharmacy data may be more appropriate for an HMO setting. Additional research is needed to develop and refine such a method.

PedCheck: A Program for Identification of Genotype Incompatibilities in Linkage Analysis

Prior to performance of linkage analysis, elimination of all Mendelian inconsistencies in the pedigree data is essential. Often, identification of erroneous genotypes by visual inspection can be very difficult and time consuming. In fact, sometimes the errors are not recognized until the stage of running linkage-analysis software. The effort then required to find the erroneous genotypes and to cross-reference pedigree and marker data that may have been recoded and renumbered can be not only tedious but also quite daunting, in the case of very large pedigrees. We have implemented four error-checking algorithms in a new computer program, PedCheck, which will assist researchers in identifying all Mendelian inconsistencies in pedigree data and will provide them with useful and detailed diagnostic information to help resolve the errors. Our program, which uses many of the algorithms implemented in VITESSE, handles large data sets quickly and efficiently, accepts a variety of input formats, and offers various error-checking algorithms that match the subtlety of the pedigree error. These algorithms range from simple parent-offspring-compatibility checks to a single-locus likelihood-based statistic that identifies and ranks the individuals most likely to be in error. We use various real data sets to illustrate the power and effectiveness of our program.

Hospital Use by Pediatric Patients: Implications for Change

We conducted an analysis of population-based records of hospitalizations for all children 1-12 years old in California in order to provide detailed descriptive diagnostic information on pediatric hospitalizations and to analyze differences in hospital use by population group. We analyzed 1992 computerized hospital discharge data for all children ages 1-5 years (n = 76,611) and 6-12 years (n = 54,827) in California acute care hospitals. We looked at the major diagnoses resulting in hospitalization and the total cost and total length of hospital stay by diagnosis. Relative risks for hospitalization by race and gender were calculated with 95% confidence intervals. Discharges among children ages 1-5 years accounted for $746 million in hospital charges and 319,059 days of hospitalization while discharges among children ages 6-12 years accounted for $580 million and 310,912 hospital days. Asthma, injuries, pneumonia, gastroenteritis, and congenital disease accounted for 46% of hospitalizations in children between 1 and 5 years old. Injury, appendicitis, asthma, mental illness, and pneumonia accounted for 45% of hospitalizations in those between 6 and 12. The risk of hospitalization varied significantly by gender and race. Many pediatric hospitalizations are preventable, and further efforts are needed to address this problem through improved access to primary care and education. Of particular significance are the racial variations in risk of hospitalization due to asthma and mental illness.

Systematic Assessment of 50 Children With Selective Mutism

To clarify the diagnostic significance of selective mutism (elective mutism in DSM-III-R). Fifty children with selective mutism were evaluated systematically by means of semistructured clinical interviews and rating scales to obtain detailed diagnostic information. All 50 children met DSM-III-R criteria for social phobia or avoidant disorder and 24 (48%) had additional anxiety disorders. Clinical measures of anxiety and behavioral symptoms supported the presence of anxiety disorders as a characteristic of selectivity mute children. Only one case each of oppositional defiant disorder and attention-deficit hyperactivity disorder was found. Persistent selective mutism typically presents in the context of anxiety disorders.

Routine serum protein analysis by capillary zone electrophoresis: Clinical evaluation

To measure the five classical protein fractions in human serum several electrophoretic techniques are available. Besides separation on cellulose acetate membrane or agarose gel, capillary zone electrophoresis (CZE) may be a useful analytical alternative in clinical routine. We have compared the Dionex CES I capillary electrophoresis system with that of the Olympus Fractoscan using specimens submitted for routine analysis. For clinical evaluation 102 samples from patients with various diseases have been analysed. Serum protein fractions were judged on separation performance, precision and the regression method ofBablok-Passing. Regression analysis revealed variable agreement between both methods with a slope ± intercept of 2.10–0.52 (α1-fraction) and 1.0–0.20 (α2-fraction) as worse and best, resectively; and the coefficient of variation of migration time: 5.9 %–6.8 % (between-run imprecision). Differences in the comparison of fractions are mainly caused by the improved resolution of CZE; e.g. one β-globulin peak on cellulose acetate is separated into two distinct protein fractions in CZE, including more detailed diagnostic information—as is also the case with γ-fraction. In some cases monoclonal gammopathy with low concentrations of immunglobulin clone can only be detected in CZE, whereas the cellulose acetate membrane (CAME) electropherogram is inconspicuous. The within-run precision (N=18) gave coefficients of variation of peak areas 1.3–5.9 % (CZE) and 1.0–3.8 % (cellulose acetate membrane). This is the first time that a complete clinical evaluation of CZE serum protein fraction analysis has been performed. CZE with its higher resolution and hence more detailed diagnostic information in some cases, showed good separation patterns, precision and correlation. Interchangeability of results showed that this CZE method is well suited for analysis of serum protein fractions in clinical routine.

Global climate change in the instrumental period

The instrumental period of climate history began in the 18th century with the commencement of routine weather observations at fixed sites. Estimates of global-mean climate (e.g. temperature and precipitation) were not possible, however, until the establishment of extensive observing networks midway through the 19th century. This paper reviews our knowledge of global climate change in the instrumental period. Time series of global-mean temperature and precipitation are examined and a comparison is made between two independent 30-year climatologies: 1931–1960 and 1961–1990. Examples are also provided of regional-scale climate changes. Such assessments are important for two reasons. First, they establish the variability of climate on the time-scale of decades, time-scales upon which it is reasonable to plan economic and socio-political activities. Second, and more specifically, they enable us to quantify the magnitude of global-mean climate change which has occurred over this period. Such detailed diagnostic climate information is a necessary, although not sufficient, prerequisite for the detection of global-scale warming which may have occurred due to the enhanced greenhouse effect. Some attention is given to explanations of the observed changes in global-mean climate.

Angiography of the Lower Extremity in Atherosclerotic vascular Disease: Current Techniques

With the vast array of technology available, detailed diagnostic information is now routinely obtained in patients with peripheral vascular disorders. In addition, percutaneous intervention and advanced surgical techniques now safely permit the patient to return to an active life, and in advanced vascular disease, the extremity can be salvaged when previously the only option was amputation. We feel strongly that the maximum amount of information about the arterial system should be obtained throughout the patient's management. In addition, these complex procedures require considerable experience and judgment, and our practice of ongoing communication with the vascular surgery staff during both the diagnostic and the therapeutic phases of the patient's treatment has been extremely beneficial.

Proton therapy for carcinoma of the nasopharynx: A study in comparative treatment planning

Radiation therapy for nasopharyngeal carcinoma is technically difficult because of the complexity of the regional anatomy and the natural history of the disease. The results of a study are presented showing how detailed diagnostic information available from MRI is helpful in defining the target volume to be irradiated and the critical normal structures. By using 3-dimensional planning techniques, an assessment was made of the relative merits of proton beam therapy and of X ray treatment for patients with early stage and locally advanced carcinoma of the nasopharynx. For both types of patient, the study suggests that the use of protons for the major part of treatment results in a more even distribution of dose to the tumor and an increase of approximately 5 Gy in median tumor dose with substantial reductions in doses to adjacent normal tissues. The superior dose distributions possible with protons should translate into improved local control and reduced morbidity. The difficulties of proton treatment planning for this site are addressed.

Systematic approach to diagnosis and coding of pediatric cardiac disease.

A new system for coding congenital heart defects and related problems was developed to facilitate the computerized storage and retrieval of detailed diagnostic information. The system is based on the segmental approach to diagnosis with comprehensive tables indicating all possible mutually exclusive intersegmental alignments and connections. Diagnostic entities rather than nomenclature are the subjects of the codes. This system represents the best effort to date to develop an all-inclusive, precise, and accurate code while insuring completeness and maximizing efficiency in data collection by the use of a highly structured code book.

Ultrasound gray‐scale pattern and guided aspiration puncture of abdominal abscesses

Various ultrasound gray-scale patterns of 45 consecutive abscesses were studied in 43 surgical and medical patients. Eleven abscess formations were unsuspected clinically, 27 had developed as a postoperative complication; 25 collections (55.6%) presented with an anechoic appearance, and 15 (33.3%) showed a mainly fluid pattern but contained a few nonreverberatory echoes. Five abscesses (11.1%) appeared with a complex solid-like pattern with large amounts of internal echoes. A total of 28 ultrasound guided diagnostic fine-needle aspirations of abscesses were performed on 26 patients without serious complications. All the aspirated samples yielded material sufficient for cytological or bacteriological examinations. Percutaneous fine-needle aspiration guided by sonography is recommended as a safe and useful diagnostic measure to confirm the nature of an ultrasonically displayed abdominal lesion suspected to be an abscess. Results from both sonography and confirmatory aspiration provide detailed topographic and diagnostic information for the choice of surgical or nonoperative management of abdominal abscess.

Frequency-shift Tympanogram

In order to get the detailed diagnostic information from the tympanogram, we devised a new tympanometric system, in that the frequency of the probe tone changed continuously from 45Hz to 5000Hz. This system was applied to 11 subjects with normal hearing and normal ear drum.The curves of the tympanogram varied from a V-shaped in low frequencies of the probe-tone to an inverted V-shap in higher frequencies showing a W-shape in mid-frequencies, as the frequency of the probe tone was shifted. The frequency that provoked the pattern change of V to W in the tympanogram was different from subject to subject, and varied from 1400Hz to 2200Hz. Additional model experiment suggested us strongly that the stiffness of the middle ear was one of the most decisive factor in determining the frequency in which the tympanogram pattern changed its V-shape to W-shape.It was also observed that the asymmetry of the tympanogram appeared as the frequency of the probe tone increased. Several causes of this asymmetry were discussed.Further study should be performed, that is, application of this system to make a differential diagnosis for the ossicular discontinuity or the ossicular fixation.

PLANETARY NEBULAE, SURVEY AND OUTLOOK.

ABSTRACT The paper reviews the current status of research on planetary nebulae, summarizing the main results of a continuing program of spectroscopic studies of planetary nebulae. Two aspects are included in this program: (1) photographic spectra with as high resolution as possible in the regions 3100 to 5100 A, (2) image-tube scanner observations with the 3-m telescope in the range 3700 to 8600 A. The objective of the program was to obtain as detailed diagnostic information as practical by observing each element in as many stages of ionization as possible, and to examine nebular regions of different excitation. Some detailed image-tube scans are shown as examples. Available data on abundances of eight elements in 28 objects are summarized. Evidence for variation of abundance of some elements with distance from the center is examined. Mention is made of some work on detection and measurement of planetaries in external galaxies.