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[Efficient diagnosis of pathological fractures].

Pathological fractures are defined as fractures, which appear at diseased and mechanically weakened bones due to systemic or local processes. Their frequency is below 5%. This study demonstrates typical results and diagnostic criteria of pathological fractures. It will be shown, how diagnostic analysis is supposed to be performed to recognize pathological fractures. Based just on the X-ray image, diagnostic algorithms should provide all tools required for the radiologist to create a final diagnosis or to refer to other appropriate imaging modalities followed by a correct diagnosis and, if necessary, to allow interdisciplinary causal therapies.

Diagnosis, Differential↗

Assessment of fiberoptic near-infrared raman spectroscopy for diagnosis of bladder and prostate cancer.

OBJECTIVES: To determine whether a fiberoptic Raman system, suitable for in vivo use, is able to differentiate between benign and malignant bladder and prostate pathologic findings in vitro. Raman spectroscopy is an optical technique that provides a measure of the molecular composition of tissue by analyzing the way that tissue scatters laser light. Laboratory studies have shown that the technique can be used to identify and characterize transitional cell carcinoma and prostate adenocarcinoma in vitro. METHODS: A total of 220 Raman spectra were recorded from 29 snap-frozen bladder samples collected at cystoscopic procedures, and 197 Raman spectra were recorded from 38 snap-frozen prostate samples collected at transurethral resection of the prostate. The spectra were correlated with the histologic features and used to construct separate diagnostic algorithms for the bladder and prostate. These algorithms were tested as to their ability to determine the pathologic finding of a sample from its Raman spectrum. RESULTS: The bladder algorithm was able to differentiate benign samples (normal and cystitis) from malignant samples (transitional cell carcinoma), with an overall accuracy of 84%. The prostate algorithm was able to differentiate benign samples (benign prostatic hyperplasia and prostatitis) from malignant samples (prostate cancer), with an overall accuracy of 86%. CONCLUSIONS: The results of this study have demonstrated that the clinical Raman system can provide an accurate and objective method to diagnose prostate and bladder cancer in vitro. Because the Raman probe is suitable for use during endoscopic, laparoscopic, or open procedures, this work paves the way for in vivo studies.

Adenocarcinoma↗

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↗

Lactic acidemia and mitochondrial disease.

Lactic acidemia is present in the majority of patients with mitochondrial oxidative defects as well as in disorders of gluconeogenesis. An understanding of the dynamics of lactic acid metabolism in the human body and the influences on lactate/pyruvate ratios exerted by changes in cellular redox state allows for the development of diagnostic algorithms based on clinical and biochemical phenotypes. Mitochondrial disorders can be due to defects in nuclear genes directly affecting the respiratory chain assembly or function, mtDNA genes affecting the respiratory chain or nuclear genes influencing mtDNA structure and viability. In this review, we look at the classification of mitochondrial disease from the perspective of not just the genetic and biochemical etiology but also from the perspective of the clinical phenotypic expression.

DNA, Mitochondrial↗

Single photon emission computed tomography in the diagnosis of pulmonary thromboembolism.

The use of single photon emission computed tomography (SPECT) as the procedure for screening, assessing the size and number of embolized areas, and evaluating the follow-up of patients with pulmonary thromboembolism (PTE) is reviewed. Details of the technique for acquiring and processing perfusion and ventilation lung SPECTs are presented. The tomographic images produced by SPECT allow the application of a less-expensive diagnostic algorithm than that classically used. This is due to the fact that the SPECT images contain more anatomical and physiological information than similar planar images. The signs of PTE in perfusion SPECT and the significance of mismatch, match, and paradoxical mismatch are discussed and illustrated with examples.

Humans↗

[Steady state multi-frequency auditory evoked potentials as a technique to determine hearing threshold].

OBJECTIVE: Since the set up of Steady-State Auditory Evoked Potentials as a routine technique, it has became necessary the establishment of clinic capabilities and limitations. In this study, we have compared SSEP to behavioural thresholds, considering the last one as "gold standard" technique. MATERIALS AND METHODS: We have recorded SSEP to multiple frequencies and behavioural thresholds in 84 ears. The obtained data were statistically processed to obtain correlations and others indicators. RESULTS: SSEP thresholds are slightly higher than behavioural, whose average difference was calculated as 23 dB. It is worth to note that this difference diminishes at high frequencies and hearing loss cases. CONCLUSIONS: SSEP to multiple frequencies technique is capable to determine auditory thresholds accurately, being closer to the behavioural value at high frequencies and high threshold values. It is necessary the establishment of exploration protocols to assure the highest accuracy of the system. In this work, a diagnostic algorithm has been proposed to reach better results by using SSEP.

Adolescent↗

Accuracy of glaucoma detection with frequency-doubling perimetry.

PURPOSE: To determine the accuracy of glaucoma detection by frequency-doubling perimetry. METHODS: Stereoview optic nerve photographs, visual field examination, intraocular pressure measurements, medical and ocular history, and a screening and full threshold frequency-doubling perimetry examination were performed in a prospective study of consecutive subjects. Inclusion criteria included age of 45 years or older, absence of ocular disease other than glaucoma, cataract, or mild drusen, and Snellen visual acuity of 20/60 or better. A total of 125 eyes in 102 glaucoma subjects and 95 eyes of 95 normal subjects were included. Each eye was classified as "normal," "glaucoma," or "uncertain" by each of three ophthalmologists on the basis of all available clinical information with the exception of frequency-doubling perimetry results. Those in the glaucoma group were subclassified as having early (n = 51), moderate (n = 42), or severe (n = 32) glaucoma on the basis of automated Humphrey visual field criteria. In the glaucoma group, two eyes from a subject were allowed to be included (23 of 102 subjects) if they differed in level of damage because they were never analyzed within the same statistical analysis. RESULTS: Several diagnostic algorithms were evaluated. Algorithms based on the most depressed single point, pair of adjacent points, and cluster of three points performed nearly identically. For the screening test, if any abnormality was identified, specificity was 95%, whereas sensitivity was 39%, 86%, and 100% for early, moderate, and severe glaucoma, respectively. For the full threshold test, with at least one point depressed to the P < 0.5% level, specificity measured 91%, whereas sensitivity was 35%, 88%, and 100% for early, moderate, and severe glaucoma, respectively. The two global indices, mean deviation and pattern standard deviation, were also evaluated and were generally less accurate. CONCLUSION: Frequency-doubling perimetry, which is rapid and easily administered, is effective at detecting moderate and severe disease and appears well suited for glaucoma screening.

Aged↗

Clinical predictors of scleral rupture after blunt ocular trauma.

We conducted a two-part study to define better the clinical predictors of scleral rupture after blunt trauma. In part 1 we ascertained the prevalence of scleral rupture among a population of patients examined in an ophthalmic emergency room with severe blunt ocular trauma over a six-month period. Scleral rupture was diagnosed in ten of 283 patients (3.5%). In part 2 we compared the clinical findings in 29 patients with scleral rupture to those of 273 patients with no scleral rupture after blunt trauma. We noted that eyes with visual acuity of light perception or less, an intraocular pressure of 5 mm Hg or less, an abnormally deep or shallow anterior chamber, or a media opacity preventing a view of fundus details by indirect ophthalmoscopy, should be considered ruptured when severe intra- or periocular hemorrhage is present. This diagnostic algorithm had a sensitivity of 100.0% (98.7% to 100.0%), specificity of 98.5% (97.1% to 99.9%), and a positive predictive value of 71.4% (66.3% to 76.5%).

Algorithms↗

Indications for using video-assisted thoracoscopic surgery to diagnose diaphragmatic injuries after penetrating chest trauma.

BACKGROUND: Video-assisted thoracoscopic surgery (VATS) has been shown to be an accurate method for identifying diaphragmatic injuries (DIs). The purpose of this investigation was to establish specific indications for the use of VATS after penetrating chest trauma. METHODS: A retrospective review of all patients undergoing VATS after penetrating chest trauma at a level 1 trauma center over an 8-year period was performed. Logistic regression was used in an attempt to identify independent predictors of DI. RESULTS: One hundred seventy-one patients underwent VATS assessment of a hemidiaphragm, and 60 patients (35%) were found to have a DI. Five independent risk factors for DI were identified from analyzing the patient records: abnormal chest radiograph, associated intraabdominal injuries, high-velocity mechanism of injury, entrance wound inferior to the nipple line or scapula, and right-sided entrance wound. CONCLUSIONS: In the largest published series of patients undergoing VATS to exclude a DI, this review identifies five independent predictors of DI after penetrating chest trauma. A diagnostic algorithm incorporating these five factors was designed with the goal of reducing the number of unrecognized DIs after penetrating chest trauma by using VATS for patients at greatest risk for such injuries.

Adult↗

Development and validation of a quantitative ELISA for the measurement of PSA concentration.

BACKGROUND: Prostate-specific antigen (PSA) has been used for the diagnosis and follow up of prostate cancer (PCa). METHODS: Mouse monoclonal antibodies (MAbs) were generated against human prostate-specific antigen (PSA) for the development of a sensitive total PSA (t-PSA) assay. Two MAbs, denoted CB-PSA.4 and CB-PSA.9, with affinities of 3.7 x 10(9) and 4.7 x 10(10) l/mol, respectively, were used to develop an enzyme-linked immunosorbent assay (ELISA) for quantifying serum t-PSA concentration. RESULTS: The detection limit (DL) of the assay was 0.1 microg/l (n=20, mean of "zero" standard+3S.D.), and the recovery of t-PSA was 96-103%. The within-run and between-day coefficients of variation (CV) ranged from 2.1% to 3.2%, and from 2.8% to 6.3% for PSA concentrations of 10 and 1 microg/l, respectively. The equimolar detection of t-PSA and free-PSA was demonstrated by two different methods, one consisted in the comparative evaluation of a sera panel (n=9) with our enzyme-linked immunosorbent assay (ELISA) and four commercial total PSA assays and the concordance with CIS bio total PSA assay. The assay had a linear range of 0.12 to 25 microg/l. CONCLUSIONS: The analytical performance characteristics of our PSA ELISA suggest that it will provide clinically useful PSA results, particularly when diagnostic algorithms are used.

Animals↗

Genotypic/phenotypic correlations in genetic hemochromatosis: evolution of diagnostic criteria.

BACKGROUND & AIMS: The identification of a candidate gene for hereditary hemochromatosis in 69%-100% of patients with hemochromatosis has resulted in a diagnostic genotypic test (C282Y). The aim of this study was to reassess the phenotypic diagnostic criteria for hemochromatosis in patients homozygous for the C282Y mutation of the HFE gene. METHODS: Transferrin saturation, ferritin, hepatic iron index, and iron removed by venesection were studied in C282Y++ homozygotes and C282Y-- putative homozygotes. RESULTS: Patients were homozygous for the C282Y mutation in 122 of 128 cases (95%). In C282Y homozygotes, the results were as follows: hepatic iron index, >1.9 in 91.3%; transferrin saturation, >55% in 90%; serum ferritin, >300 microg/L in 96% of men and >200 microg/L in 97% of women; and iron removed, >5 g in 70% of men and 73% of women. There were four homozygotes for C282Y with no biochemical evidence of iron overload. CONCLUSIONS: The sensitivity of the phenotypic tests in decreasing order was as follows: serum ferritin, hepatic iron index, transferrin saturation, and iron removed by venesection. Although the genetic test is useful in the diagnostic algorithm, this study has shown both iron-loaded patients without the mutation and homozygous patients without iron overload.

Adult↗

Methodology of serial ECG classification using an adaptation of the NOVACODE for Q wave myocardial infarction in the Bypass Angioplasty Revascularization Investigation (BARI).

Serial electrocardiographic (ECG) changes are a critical component of the diagnostic algorithm for classification of myocardial ischemic events in large-scale clinical trials. This study describes a computerized serial ECG classification program developed at the St. Louis University Core ECG Laboratory for use in the Bypass Angioplasty Revascularization Investigation (BARI) trial, in which patients with multivessel coronary artery disease were randomized to receive either coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. The St. Louis University program detects and codes serial changes in Q, ST, and T wave items according to Minnesota code (MC) criteria using a modified NOVACODE hierarchical classification system. Measurements using a seven-power calibrated coding loupe are used to generate the MC from a customized software program. Significant minor or major changes are detected by the serial comparison program and referred to a physician coder for verification. Serial comparison coding rules are used to adjust for weaknesses in the standard MC classification system resulting from instability at decision boundaries. Of 4,244 BARI randomized and registry study participants with follow-up ECGs received at the Core ECG Laboratory as of March 1995, a grade 2 MC Q wave progression was noted in 568 participants (13.4%) using MC criteria alone, as compared with 367 (8.6%) after the St. Louis University coding rules were applied. The incidence of grade 1 MC Q wave progressions was 16.4% (697/4,244) versus 6.1% (259/4,244) when the St. Louis University program was applied. Intraobserver variability for grade 2 Q wave progression codes determined from a sample of 812 serial.

Algorithms↗

Autofluorescence guided biopsy for the early diagnosis of bladder carcinoma.

PURPOSE: We validate the usefulness of laser-induced autofluorescence for the detection of bladder carcinoma. MATERIALS AND METHODS: We obtained and analyzed fluorescence spectra from 75 patients in whom bladder cancer was suspected. Tissue fluorescence was excited by a nitrogen laser using a quartz optical fiber placed in gentle contact with the area of interest. The laser-induced autofluorescence spectrum was recorded using an intensified optical multichannel analyzer system. Spectra were corrected for the spectral response of the optical system, and the ratios of laser-induced autofluorescence intensities (I) at 385 and 455 nm. (I385/I455) were determined. We had previously established this ratio as a diagnostic algorithm. We included only suspicious bladder lesions (erythematous, edematous, raised and so forth) that were difficult to diagnose by cystoscopy as well as areas from which random biopsies were obtained. The fluorescence ratio algorithm was applied to 130 bladder areas. RESULTS: Of the 130 biopsies obtained during routine cystoscopy 107 (82%) were nonmalignant by histological classification. In contrast, because laser-induced autofluorescence effectively guides biopsies towards malignant lesions, only 30 biopsies (72% fewer) would have been obtained from nonmalignant tissue if the fluorescence ratio that identifies 95% of malignant lesions (95th percentile) had been selected as the decision criterion during standard cystoscopy. CONCLUSIONS: By guiding the surgeon to suspicious lesions that are most likely to be malignant, laser-induced autofluorescence substantially decreases the number of biopsies obtained from nonmalignant tissue during cystoscopy to diagnose bladder carcinoma.

Aged↗

Isolated retrovesical and extrarenal retroperitoneal hydatidosis: clinical study of 10 cases and literature review.

PURPOSE: Isolated extrarenal retroperitoneal echinococcal cyst is a rare manifestation of hydatid disease. We review the clinical findings of a series of isolated retrovesical and retroperitoneal hydatid cysts in an endemic area, with special emphasis on diagnostic pitfalls. MATERIALS AND METHODS: A retrospective 15-year review in a rural area of central Spain (600,000 population), with a global incidence of hydatidosis of 10 new cases per 100,000 population per year, revealed 10 patients (0.1 cases per 100,000 per year) with surgically treated primary extrarenal retroperitoneal echinococcosis and absence of other hydatid cysts in any organ. Clinical, radiological and laboratory data are analyzed. The literature of the last 15 years on hydatid disease with a primary retroperitoneal and retrovesical location is reviewed. RESULTS: A total of 42 cases of isolated retrovesical (25) and retroperitoneal (17) hydatidosis was compiled. Male predominance of 2.5:1 was noted and age ranged from 8 to 79 years (mean 42.2 +/- 5.4). The most frequent presentation was a palpable mass in 29% of the cases followed by flank pain in 24%, frequency in 17% and urinary retention in 14% of the cases. Hydatiduria of the urinary tract was present in 9.5% of the cases. Different serological investigations were performed in 45% of the cases with positive results in 68%. The lesion had been surgically removed in all cases. Therapy and followup of each patient were analyzed. CONCLUSIONS: An isolated retrovesical, retroperitoneal or even retrocrural cyst can be the unique manifestation of hydatid disease. Although difficult, preoperative diagnosis is desirable for the selection of a surgical approach and prevention of allergic reactions and operative spillage. A diagnostic algorithm and several therapeutic guidelines are proposed.

Adolescent↗

Abdominal pain in infants and children.

The challenges of childhood abdominal pain are to treat the majority of children with self-limited conditions of obscure but benign causes and to identify the child with a rare, life-threatening cause of pain. The diagnostic algorithm of abdominal pain during childhood is best compartmentalized into three groups: infants, preschoolers, and school-age children. In infants, bilious vomiting heralds a life-threatening or surgically indicated disorder. Most nonsurgical conditions are related to gastroenteritis, constipation, and reflux. The majority of children with abdominal pain experience spontaneous resolution of their symptoms without specific management. For every 15 school-age children with abdominal pain, 1, at most, will have a serious condition such as appendicitis. Parents and children appreciate a careful appraisal of the symptoms, and the physician should listen to their concerns and perform a thorough examination. Laboratory or radiologic studies are rarely indicated.

Abdomen, Acute↗

Diagnosis of deep venous thrombosis and pulmonary embolism.

Diagnostic evaluation in the patient with suspected deep vein thrombosis (DVT) and pulmonary embolism (PE) includes a clear correlation between clinical probability, test selection and test interpretation. Real-time B-mode ultrasound with color Doppler remains the imaging technique of choice in suspected DVT. The ventilation/perfusion (V/Q) lung scan is the preferred diagnostic modality in suspected PE. The D-dimer assay may be useful in excluding PA. New diagnostic techniques, including spiral computerized tomography may further modify the diagnostic algorithm.

Humans↗

[Screening for lung cancer with low-dose spiral CT: results in 150 asymptomatic subjects].

BACKGROUND AND OBJECTIVE: Our aim is to present initial baseline data from a screening trial on low-dose spiral computed tomography (CT). We describe enrollment criteria and a diagnostic algorithm based on initial low-dose CT findings. SUBJECTS AND METHOD: From September 2000 to May 2001, 150 asymptomatic smokers (age range 40-78 years; mean 55 years) were studied using non-enhanced low-dose spiral CT of the chest. Repeated short-term high resolution CT follow-up was performed for non-calcified pulmonary nodules smaller than 10 mm in diameter. Non-calcified pulmonary nodules 10 mm or larger were considered as potentially malignant and a complementary positron emission tomography (PET) exam was recommended. RESULTS: 54 non-calcified pulmonary nodules were found in 34 out of 141 (24.15%) symptom-free subjects. The diameter was 5 mm or shorter in 24 participants (70.6%), 6-10 mm in 7 (20.6%) and longer than 10 mm in 3 (8.8%) individuals. One patient with a non-calcified pulmonary nodule of at least 10 mm underwent a complementary PET exam, which was positive. Biopsy of this nodule demonstrated lung cancer (squamous cell carcinoma). CT follow-up over one year was decided in the other two subjects having non-calcified pulmonary nodules longer than 10 mm, as no radiographic signs indicative of malignancy were observed in the baseline scan. CONCLUSION: Following this low-dose CT based screening programme, detection of early-stage lung cancer in asymptomatic subjects at high risk of developing the disease is feasible. Further studies are however necessary to pursue more definitive results.

Adult↗

[Factors predicting detectable viral load in patients with highly active antiretroviral treatment].

BACKGROUND AND OBJECTIVE: Knowledge of the variables predicting detectable viral load in patients with highly active antiretroviral treatment. PATIENTS AND METHOD: Observational and cross-sectional study in patients with antiretroviral treatment receiving two nucleoside reverse transcriptase inhibitors and one protease inhibitor. Several sociodemographic and clinic variables were registered. Two models were designed in order to assess the adherence: I. combining self-report and pharmacy criteria, and II. including drug plasma levels in adherent patients with the two former criteria and detectable viral load. Logistic regression analysis with variables found to be associated with detectable viral load in the univariate analysis, diagnostic algorithm and ROC statistics were performed in order to select the best model to predict detectable viral load. RESULTS: Among of 136 patients studied, 39 (28.7%) had detectable viral load. Patients less than 35 years old (OR = 2.68), intravenous drug users or heterosexual contacts as the way of HIV infection (OR = 6.42), patients not fully convinced of the capacity of mutation of the HIV by poor adherence (OR = 3.25) and patients considered non-adherent according to the drug plasma levels criteria (OR = 6.91) had more frequently detectable viral load. The best model to predict detectable viral load would include patients considered non-adherent according to the two models used, and moreover, patients where another of the factors of risk were detected; the prevalence of detectable viral load in these was of 10% versus 43%. CONCLUSION: Adherence to HAART is a key factor to predict detectable viral load, specially in young patients, infected by intravenous drug use or heterosexual contacts, and patients not convinced of the importance of the adherence.

Adolescent↗