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At least 127 records · Page 7Linked to original sources

Factors affecting diagnostic accuracy of CT-guided coaxial cutting needle lung biopsy: retrospective analysis of 631 procedures.

PURPOSE: To analyze variables affecting diagnostic accuracy of computed tomography (CT)-guided percutaneous coaxial cutting needle biopsy of lung lesions. MATERIALS AND METHODS: A retrospective analysis of factors affecting diagnostic accuracy of CT-guided percutaneous coaxial cutting needle lung biopsy was performed in 631 consecutive procedures with confirmed final diagnoses. Benign and malignant needle biopsy results were cross-examined with correct and incorrect final outcomes to determine diagnostic accuracy. Factors affecting diagnostic accuracy were determined by multivariate logistic regression analysis of variables thought to affect diagnostic accuracy. A P value less than 0.05 was interpreted as statistically significant. RESULTS: The overall diagnostic accuracy of CT-guided percutaneous coaxial cutting needle biopsy of lung lesions was 95% (95% CI: 92.7%-96.2%). Sensitivity was 93%, specificity 98%, negative predictive value 6%, positive predictive value 99%, false-positive rate 0.7%, and false-negative rate 15%. The factors affecting diagnostic accuracy were final diagnoses (benign, 86%; malignant, 99%; chi(2) test, P < 0.001) and lesion size (lesions <1.5 cm, 84%; lesions 1.5-5.0 cm, 96%; lesions >5 cm, 93%; chi(2) test, P = 0.06). CONCLUSION: Benign lung lesions, lung lesions smaller than 1.5 cm (which pose technical difficulty), and lung lesions larger than 5 cm (which are associated with a higher necrosis rate) affect diagnostic accuracy of CT-guided percutaneous coaxial cutting needle biopsy of lung lesions.

Biopsy, Needle↗

The multidisciplinary team meeting improves staging accuracy and treatment selection for gastro-esophageal cancer.

The object of this article is to assess current staging accuracies for individual modalities and to investigate the influence of the multidisciplinary team (MDT) on clinical staging accuracies and treatment selection for patients with gastro-esophageal cancer. Patients newly diagnosed with gastric or esophageal cancer and who were deemed suitable for surgical resection by the MDT were studied. Patients were staged with a combination of computerized tomography (CT), endoscopic ultrasound (EUS) and laparoscopic ultrasound (LUS). Additionally, the MDT determined an overall clinical stage for each patient after discussion at the MDT meeting. Treatments were selected according to this final clinical stage. Final histopathological staging (pTNM) was available for all patients and was used as the gold standard for determining staging accuracy. Suitability of treatment selection was assessed once final pTNM was available. One hundred and eighteen patients were studied. Endoscopic ultrasound was the most accurate individual staging modality for the loco-regional assessment of esophageal tumors (T stage accuracy 78%, N stage accuracy 70%). Laparoscopic ultrasound was the most accurate modality in T staging of gastric cancers (91%). The MDT stage was more accurate than each individual staging modality for T and N staging for both gastric and esophageal cancers (accuracy range: 88-89%) and was better for the assessment of nodal disease than each individual modality (CT P < 0.001, EUS P < 0.01, LUS P < 0.01). Overall staging accuracy as determined at the MDT meeting was increased and resulted in only 2/118 (2%) patients being under-treated. The MDT significantly improves staging accuracy for gastro-esophageal cancer and ensures that correct management decisions are made for the highest number of individual patients.

Adenocarcinoma↗

Accuracy of computed tomography guided core needle biopsy of musculoskeletal tumours.

BACKGROUND: The accurate diagnosis of musculoskeletal tumours is important for successful treatment. Image guided biopsy is gaining increasing acceptance for obtaining tissue for diagnosis. The aim of the present study is to assess the accuracy of computed tomography (CT)-guided core needle biopsy of musculoskeletal tumours. METHODS: This is a retrospective study on a series of 127 patients with a musculoskeletal tumour. The biopsies were performed over a 4-year period from 1998 to 2001. The accuracy of the CT-guided core needle biopsy was determined by comparing the histology of the biopsy with the final histology of the specimen obtained at open biopsy or surgical resection of the tumour. The effective accuracy was determined by the accuracy of the biopsy to distinguish between a benign and malignant tumour. RESULTS: Computed tomography guided core needle biopsy in the present series has an overall accuracy of 80.3%. The effective accuracy as determined by a malignant versus benign lesion was 89%. There were 86 malignant tumours with a biopsy accuracy of 81.4% and there were 41 benign tumours with a biopsy accuracy of 78%. The positive predictive value (PPV) of a malignant tumour is 98.9% and the PPV of benign tumour 90.2%. The most common site of biopsy was from the femur and thigh, together accounting for 39.4% of the tumours. The most common tumours in this series were liposarcoma (n = 12), osteosarcoma (n = 11) and giant cell tumour (n = 11). There were no reported complications arising from the biopsy. CONCLUSION: Computed tomography guided core needle biopsy is a safe and effective procedure that is important in the diagnosis and management of musculoskeletal tumours. It should be performed in a specialized institution with a multidisciplinary musculoskeletal tumour team.

Adolescent↗

Indicators of accuracy of consumer health information on the Internet: a study of indicators relating to information for managing fever in children in the home.

OBJECTIVES: To identify indicators of accuracy for consumer health information on the Internet. The results will help lay people distinguish accurate from inaccurate health information on the Internet. DESIGN: Several popular search engines (Yahoo, AltaVista, and Google) were used to find Web pages on the treatment of fever in children. The accuracy and completeness of these Web pages was determined by comparing their content with that of an instrument developed from authoritative sources on treating fever in children. The presence on these Web pages of a number of proposed indicators of accuracy, taken from published guidelines for evaluating the quality of health information on the Internet, was noted. MAIN OUTCOME MEASURES: Correlation between the accuracy of Web pages on treating fever in children and the presence of proposed indicators of accuracy on these pages. Likelihood ratios for the presence (and absence) of these proposed indicators. RESULTS: One hundred Web pages were identified and characterized as "more accurate" or "less accurate." Three indicators correlated with accuracy: displaying the HONcode logo, having an organization domain, and displaying a copyright. Many proposed indicators taken from published guidelines did not correlate with accuracy (e.g., the author being identified and the author having medical credentials) or inaccuracy (e.g., lack of currency and advertising). CONCLUSIONS: This method provides a systematic way of identifying indicators that are correlated with the accuracy (or inaccuracy) of health information on the Internet. Three such indicators have been identified in this study. Identifying such indicators and informing the providers and consumers of health information about them would be valuable for public health care.

Child↗

Pneumonia and ARDS in patients receiving mechanical ventilation: diagnostic accuracy of chest radiography.

This study was done to evaluate the diagnostic accuracy of bedside chest radiography for pneumonia, adult respiratory distress syndrome (ARDS), or both in patients receiving mechanical ventilation. The series consisted of 40 patients; diagnostic accuracy was defined as the area under the receiver operating characteristic curve. Overall diagnostic accuracy for ARDS was 0.84. Overall diagnostic accuracy for pneumonia was 0.52. Review of previous radiographs and knowledge of clinical data did not enhance diagnostic accuracy for ARDS or pneumonia. Diagnostic accuracy for pneumonia was minimally reduced when ARDS was present. There was an increase in false-negative results because the diffuse areas of increased opacity in ARDS obscured the radiographic features of pneumonia. The authors conclude that chest radiography is of limited value for the diagnosis of pneumonia in patients receiving mechanical ventilation. The high false-negative and false-positive ratings for pneumonia resulted in a low diagnostic accuracy. The high diagnostic accuracy for ARDS was primarily due to the well-defined radiographic appearance of ARDS and few false-positive ratings.

Adolescent↗

Prostate cancer: relative effects of demographic, clinical, histologic, and MR imaging variables on the accuracy of staging.

PURPOSE: To determine the effects on the accuracy of staging prostate gland cancer of diagnostic prediction rules based on demographic, clinical, histologic, and magnetic resonance (MR) image variables. MATERIALS AND METHODS: A total of 200 cases from four medical centers were evaluated by nine radiologists experienced in MR imaging. The accuracies of the four diagnostic variables (age, prostate specific antigen level, Gleason tumor grade, and MR imaging findings) were measured, both singly and combined in a particular sequence, by calculating the area index of the receiver operating characteristic curve. RESULTS: The accuracy of staging with single variables (age, 0.58; prostate specific antigen level, 0.74; Gleason grade 0.73, MR image findings, 0.74) increased as the variables were optimally merged. The first two variables combined to yield an accuracy of 0.74; the first three combined to yield an accuracy of 0.81; and all four variables resulted in an accuracy of 0.86. In a clinically important subset of 69 cases for which antigen level and Gleason grade together were inconclusive for the purposes of staging, the addition of MR imaging findings resulted in an increase in accuracy from 0.55 to 0.73. CONCLUSION: Optimal merging of diagnostic test results yields an improvement in the accuracy of prostate cancer staging.

Age Factors↗

Analysis and improvement of fitness exploitation in XCS: bounding models, tournament selection, and bilateral accuracy.

The evolutionary learning mechanism in XCS strongly depends on its accuracy-based fitness approach. The approach is meant to result in an evolutionary drive from classifiers of low accuracy to those of high accuracy. Since, given inaccuracy, lower specificity often corresponds to lower accuracy, fitness pressure most often also results in a pressure towards higher specificity. Moreover, fitness pressure should cause the evolutionary process to be innovative in that it combines low-order building blocks of lower accurate classifiers, to higher-order building blocks with higher accuracy. This paper investigates how, when, and where accuracy-based fitness results in successful rule evolution in XCS. Along the way, a weakness in the current proportionate selection method in XCS is identified. Several problem bounds are derived that need to be obeyed to enable proper evolutionary pressure. Moreover, a fitness dilemma is identified that causes accuracy-based fitness to be misleading. Improvements are introduced to XCS to make fitness pressure more robust and overcome the fitness dilemma. Specifically, (1) tournament selection results in a much better fitness-bias exploitation, and (2) bilateral accuracy prevents the fitness dilemma. While the improvements stand for themselves, we believe they also contribute to the ultimate goal of an evolutionary learning system that is able to solve decomposable machine-learning problems quickly, accurately,and reliably. The paper also contributes to the further understanding of XCS in general and the fitness approach in XCS in particular.

Algorithms↗

The effect of stimulus strength on the speed and accuracy of a perceptual decision.

Both the speed and the accuracy of a perceptual judgment depend on the strength of the sensory stimulation. When stimulus strength is high, accuracy is high and response time is fast; when stimulus strength is low, accuracy is low and response time is slow. Although the psychometric function is well established as a tool for analyzing the relationship between accuracy and stimulus strength, the corresponding chronometric function for the relationship between response time and stimulus strength has not received as much consideration. In this article, we describe a theory of perceptual decision making based on a diffusion model. In it, a decision is based on the additive accumulation of sensory evidence over time to a bound. Combined with simple scaling assumptions, the proportional-rate and power-rate diffusion models predict simple analytic expressions for both the chronometric and psychometric functions. In a series of psychophysical experiments, we show that this theory accounts for response time and accuracy as a function of both stimulus strength and speed-accuracy instructions. In particular, the results demonstrate a close coupling between response time and accuracy. The theory is also shown to subsume the predictions of Piéron's Law, a power function dependence of response time on stimulus strength. The theory's analytic chronometric function allows one to extend theories of accuracy to response time.

Decision Making↗

The degree to which accuracy of preoperative staging of laryngeal carcinoma has been enhanced by computed tomography.

In this retrospective study, the accuracy of preoperative staging by high-resolution CT and clinical evaluation (indirect-direct laryngoscopy) is compared to the postsurgical pathologic staging of laryngeal cancer. Forty-two patients who were admitted to St. Louis University Hospital between the years of 1978 to 1985 with diagnoses of laryngeal cancer were included. All patients received high-resolution CT scan of the larynx preoperatively and subsequently underwent total or partial laryngectomy. None of these patients received preoperative radiotherapy. The accuracy of the clinical vs. CT staging--as well as the accuracy of the staging by combination of the two modalities--was determined by comparison with the postsurgical pathologic staging. The accuracy was assessed separately for glottic, supraglottic, and transglottic carcinoma. The accuracy of CT staging for glottic carcinoma was 75%. However, clinical evaluation in this group of lesions was very reliable, offering 92.9% accuracy. The accuracy of CT staging increased in the supraglottic and transglottic lesions, to become superior to the clinical staging. With combined information gained by both examinations, the preoperative staging accuracy was 91.4% for supraglottic carcinoma and 87.5% for transglottic carcinoma. It is, therefore, recommended that high-resolution CT should be included in the preoperative staging of laryngeal cancer.

Carcinoma↗

OXBench: a benchmark for evaluation of protein multiple sequence alignment accuracy.

BACKGROUND: The alignment of two or more protein sequences provides a powerful guide in the prediction of the protein structure and in identifying key functional residues, however, the utility of any prediction is completely dependent on the accuracy of the alignment. In this paper we describe a suite of reference alignments derived from the comparison of protein three-dimensional structures together with evaluation measures and software that allow automatically generated alignments to be benchmarked. We test the OXBench benchmark suite on alignments generated by the AMPS multiple alignment method, then apply the suite to compare eight different multiple alignment algorithms. The benchmark shows the current state-of-the art for alignment accuracy and provides a baseline against which new alignment algorithms may be judged. RESULTS: The simple hierarchical multiple alignment algorithm, AMPS, performed as well as or better than more modern methods such as CLUSTALW once the PAM250 pair-score matrix was replaced by a BLOSUM series matrix. AMPS gave an accuracy in Structurally Conserved Regions (SCRs) of 89.9% over a set of 672 alignments. The T-COFFEE method on a data set of families with <8 sequences gave 91.4% accuracy, significantly better than CLUSTALW (88.9%) and all other methods considered here. The complete suite is available from http://www.compbio.dundee.ac.uk. CONCLUSIONS: The OXBench suite of reference alignments, evaluation software and results database provide a convenient method to assess progress in sequence alignment techniques. Evaluation measures that were dependent on comparison to a reference alignment were found to give good discrimination between methods. The STAMP Sc Score which is independent of a reference alignment also gave good discrimination. Application of OXBench in this paper shows that with the exception of T-COFFEE, the majority of the improvement in alignment accuracy seen since 1985 stems from improved pair-score matrices rather than algorithmic refinements. The maximum theoretical alignment accuracy obtained by pooling results over all methods was 94.5% with 52.5% accuracy for alignments in the 0-10 percentage identity range. This suggests that further improvements in accuracy will be possible in the future.

Amino Acid Sequence↗

Reporting of measures of accuracy in systematic reviews of diagnostic literature.

BACKGROUND: There are a variety of ways in which accuracy of clinical tests can be summarised in systematic reviews. Variation in reporting of summary measures has only been assessed in a small survey restricted to meta-analyses of screening studies found in a single database. Therefore, we performed this study to assess the measures of accuracy used for reporting results of primary studies as well as their meta-analysis in systematic reviews of test accuracy studies. METHODS: Relevant reviews on test accuracy were selected from the Database of Abstracts of Reviews of Effectiveness (1994-2000), which electronically searches seven bibliographic databases and manually searches key resources. The structured abstracts of these reviews were screened and information on accuracy measures was extracted from the full texts of 90 relevant reviews, 60 of which used meta-analysis. RESULTS: Sensitivity or specificity was used for reporting the results of primary studies in 65/90 (72%) reviews, predictive values in 26/90 (28%), and likelihood ratios in 20/90 (22%). For meta-analysis, pooled sensitivity or specificity was used in 35/60 (58%) reviews, pooled predictive values in 11/60 (18%), pooled likelihood ratios in 13/60 (22%), and pooled diagnostic odds ratio in 5/60 (8%). Summary ROC was used in 44/60 (73%) of the meta-analyses. There were no significant differences in measures of test accuracy among reviews published earlier (1994-97) and those published later (1998-2000). CONCLUSIONS: There is considerable variation in ways of reporting and summarising results of test accuracy studies in systematic reviews. There is a need for consensus about the best ways of reporting results of test accuracy studies in reviews.

Bias↗

Quantification of true in vivo (application) accuracy in cranial image-guided surgery: influence of mode of patient registration.

OBJECTIVE: Very few studies have attempted to quantify the true (application) accuracy of image-guidance systems during craniotomy. This is, in part, because of the lack of millimetric intraoperative targets to allow such measurements. Few in vivo studies have compared the influence of mode of patient registration on subsequent true accuracy. METHODS: Seven modes of patient registration (anatomic landmarks, 5 or 10 adhesive fiducials, bone-implanted fiducials [Stryker-Leibinger], surface matching using 45 or 100 points over scalp convexity or nose/auditory meatus contours) were compared. Thirty patients were involved in the study. Millimetric targets (bone drill holes or deep 1-mm titanium hemoclips) were placed then localized and saved at surgery. These targets were then identified on postoperative volumetric computed tomography fused with operative data sets. Localization errors of the targets were measured for each registration on an optical image-guidance system (StealthStation). RESULTS: Only implanted cranial fiducials had a statistically significant accuracy advantage (1.7 +/- 0.7 mm). All other registrations had similar accuracies (approximately 4.0 +/- 1.7 mm) except anatomic landmarks, which were worse (4.8 +/- 1.9 mm). Calculated accuracies (root mean squared) had no predictive value for true (application) accuracies. CONCLUSION: Not surprisingly, application accuracy of image-guidance is worse without implanted cranial markers. Unexpectedly, there was no major difference in localization of deep targets between the other registrations tested in this study. Care must be taken when using image-guidance tools to consider error introduced by registration. Cranium-implanted fiducials should be considered when high accuracy and reproducibility are needed.

Anthropometry↗

Evidence of bias and variation in diagnostic accuracy studies.

BACKGROUND: Studies with methodologic shortcomings can overestimate the accuracy of a medical test. We sought to determine and compare the direction and magnitude of the effects of a number of potential sources of bias and variation in studies on estimates of diagnostic accuracy. METHODS: We identified meta-analyses of the diagnostic accuracy of tests through an electronic search of the databases MEDLINE, EMBASE, DARE and MEDION (1999-2002). We included meta-analyses with at least 10 primary studies without preselection based on design features. Pairs of reviewers independently extracted study characteristics and original data from the primary studies. We used a multivariable meta-epidemiologic regression model to investigate the direction and strength of the association between 15 study features on estimates of diagnostic accuracy. RESULTS: We selected 31 meta-analyses with 487 primary studies of test evaluations. Only 1 study had no design deficiencies. The quality of reporting was poor in most of the studies. We found significantly higher estimates of diagnostic accuracy in studies with nonconsecutive inclusion of patients (relative diagnostic odds ratio [RDOR] 1.5, 95% confidence interval [CI] 1.0-2.1) and retrospective data collection (RDOR 1.6, 95% CI 1.1-2.2). The estimates were highest in studies that had severe cases and healthy controls (RDOR 4.9, 95% CI 0.6-37.3). Studies that selected patients based on whether they had been referred for the index test, rather than on clinical symptoms, produced significantly lower estimates of diagnostic accuracy (RDOR 0.5, 95% CI 0.3-0.9). The variance between meta-analyses of the effect of design features was large to moderate for type of design (cohort v. case-control), the use of composite reference standards and the use of differential verification; the variance was close to zero for the other design features. INTERPRETATION: Shortcomings in study design can affect estimates of diagnostic accuracy, but the magnitude of the effect may vary from one situation to another. Design features and clinical characteristics of patient groups should be carefully considered by researchers when designing new studies and by readers when appraising the results of such studies. Unfortunately, incomplete reporting hampers the evaluation of potential sources of bias in diagnostic accuracy studies.

Clinical Trials as Topic↗

Predicting breeding values and accuracies from group in comparison to individual observations.

Individual observations are routinely used in livestock evaluations. In some cases, pooled data representing the joint but not individual performance of a group of animals may be available. For example, pooled feed intake may be measured on a pen of livestock. The usual mixed model approach to genetic evaluation can still be applied as an exact method in this setting, provided incidence and residual variance-covariance matrices are suitably modified to account for the pooling. Approximate evaluations may be achieved by treating average performance as if it pertained to each individual in the pool. Theoretical accuracies can be obtained as a function of elements of the inverse coefficient matrix. A 3-generation data set representing 1,000 animals with feed intake observations from 49 sires and 200 maternal grand sires was simulated with heritability of 0.34. Individual records were pooled to represent circumstances in which animals with records were collectively measured. Animals were allocated into pens at random, by sire, or by maternal grand sire. Simulation was replicated with unique fixed effects for each pen. Following evaluation from each method, the empirical accuracy or product-moment correlation between true (simulated) and estimated merit could be quantified. The analysis of individual observations resulted in empirical accuracy of 0.63 for animals on test and 0.77 for their sires. Pooling the observations in pens of 2, 4, or 12 animals reduced empirical accuracies for animals on test to 0.50, 0.41, and 0.21 when pooling was at random and 0.53, 0.47, and 0.34 when pooling was by sire. Simulating a fixed pen effect representing 10% phenotypic variation, but ignoring that effect in the evaluation minimally reduced empirical accuracies to 0.52, 0.46, and 0.33 when pooling by sire. Theoretical accuracies were in close agreement with empirical accuracies when the exact method was used. The approximate method that treated averages of pooled data as if they were individually observed overstated accuracy and should not be used. Selection on the basis of pooled observations can be almost as effective as using individual observations when pool sizes are small. The exact method to account for pooled data is no more complex than conventional procedures.

Animals↗

Geometric accuracy in robot-assisted total hip replacement surgery.

OBJECTIVE: Robot-Assisted Surgery in Total Hip Replacement (RAS-THR) has become a fairly widespread procedure for hip replacement surgery in Europe. However, data on the geometric accuracy of the overall process have so far been unavailable. The equipment manufacturers have only published data on the accuracy of certain elements of the procedure (e.g., the accuracy of the robot system). This study aimed to investigate the overall geometric accuracy of the complete process of RAS-THR, as well as the influence of some of the individual component steps. MATERIALS AND METHODS: An anthropomorphic phantom has been developed representing the hip and upper leg region of a human body. The entire RAS-THR procedure can be carried out using this phantom. Studies were conducted to investigate the overall accuracy of the process, as well as the influence of some individual steps in the procedure, using both the ROBODOC and CASPAR systems. RESULTS: Overall geometric accuracy of the RAS-THR process was found to be within a standard deviation of 0.5 mm and 0.3 degrees in the critical directions. Most individual steps in the process make similar contributions to the overall variation. The two robot systems examined offer comparable accuracy. CONCLUSION: Initial results seem to indicate that the RAS-THR process is acceptably accurate. However, acceptance criteria for the necessary geometric accuracy have not yet been defined.

Arthroplasty, Replacement, Hip↗

Accuracy of migration analysis in hip arthroplasty. Digitized and conventional radiography, compared to radiostereometry in 51 patients.

We assessed the accuracy of migration measurements on conventional and digitized radiographs of total hip arthroplasties by comparing the results with radiostereometry (RSA). 4 stem and 3 acetabular designs were studied. 2 of the stem designs and 1 cup design were uncemented. 180 manual and 202 digitized measurements were done on 120 conventional radiographic examinations. The readings on digitized radiographs did not differ from the manual measurements on the same radiographs. A comparison of the measurements from plain radiographs and with RSA of the femoral stems revealed an accuracy (absolute mean + 2 SD) of between 3.9 and 12.3 mm, depending on the choice of landmarks. The greatest accuracy was obtained by using tantalum markers inserted into the greater or the lesser trochanter and the shoulder of the stem. The most medial point of the lesser trochanter proved to be the best bony landmark. Measurements, including both the center of the femoral head and the greater trochanter, were associated with poor accuracy. The accuracy as regards horizontal cup migration varied from 4.4 to 6.5 mm and the accuracy as regards vertical migration varied between 4.4 and 6.3 mm. The intraobserver error (2 SD) ranged from 1.6 mm to 5.6 mm, The corresponding figures for the inter-observer error were 2.6 mm and 6.6 mm, respectively. One of the cemented cup designs was associated with inferior accuracy. Stem design did not affect the accuracy.

Bias↗

Comparison of needle core biopsy and fine-needle aspiration for diagnostic accuracy in musculoskeletal lesions.

CONTEXT: Needle core biopsy has been reported to be the choice of biopsy for musculoskeletal tumors. Fine-needle aspiration, on the other hand, has been widely accepted for nonmusculoskeletal tumors, but is only used in selected medical centers for musculoskeletal tumors. While fine-needle aspiration appears to have advantages to needle core biopsy in the aspects of simplicity and cost, the diagnostic accuracy should be the most critical parameter in determining the choice of biopsy. However, few studies comparing the diagnostic accuracy of these 2 biopsy methods have been performed. OBJECTIVE: This study was designed to compare the diagnostic accuracy of fine-needle aspiration and needle core biopsy in musculoskeletal tumors. DESIGN: Prospective study was performed in patients aged 10 years or older. Diagnostic accuracy was compared in 50 consecutive concurrent needle core biopsies and fine-needle aspirations of musculoskeletal lesions. RESULTS: For primary musculoskeletal lesions, fine-needle aspiration achieved a diagnostic accuracy rate of 88% for nature of lesion, 64% for specific diagnosis, 78% for histologic grading, and 74% for histologic typing. Needle core biopsy achieved an accuracy rate of 93% for nature of lesions, 83% for specific diagnosis, 83% for histologic grading, and 90% for histologic typing. Both biopsy methods have a higher diagnostic accuracy rate for high-grade tumors than for low-grade or benign lesions in determining the nature, specific diagnosis, and histologic grading. CONCLUSIONS: The needle core biopsy has a higher diagnostic accuracy than fine-needle aspiration in all aspects, including determining the nature of the tumor, establishing the histologic type and grade, and achieving a specific diagnosis.

Adolescent↗

[Accuracy of quantitative coronary angiography for different directions of the coronary artery].

We evaluated the effect of changes in the direction of the coronary artery in terms of the accuracy and precision of vessel diameter measurement in a quantitative coronary angiography system (QCA system). Vessel phantoms sized 0.3, 0.5, 1.0, 1.5, 2.0, and 2.5 mm in diameter were evaluated. The phantoms were aligned on an acrylic plate, and the angle to the television (TV) camera was altered. The deployed angles were 0 (perpendicular), 45, 90, and 135 degrees in clockwise order. The phantoms were imaged with matrices of 1024 x 1024 (1024(2)), 512 x 512 (512(2)), and 512 x 1024. Image size was 7 inches, and the frame rate was 15 frames per second. Minimal lumen diameters were measured on the ACA system. The results revealed that, in the 1024(2) matrix, overall accuracy for the 90-degree angle was significantly underestimated compared with the 0-degree angle (-0.14 vs. -0.014 mm; p=0.007). Accuracy for the 90-degree angle was better than that for the 0-degree angle when the vessel diameter was 1 mm or smaller (-0.02+/-0.16 vs. 0.10+/-0.22 mm). In addition, precision was better at the 90-degree angle than with the other angles in the 1024(2) matrix (overall precision=0.002 mm). In the 512(2) matrix, overall accuracy for the 90-degree angle was significantly underestimated compared with the 45-degree angle (-0.077 vs. 0.096 mm; p=0.02). In addition, accuracy for the 90-degree angle was better than that for the 45-degree angle below 1 mm (0.05+/-0.24 mm vs. 0.26+/-0.47 mm). In terms of overall accuracy, the 45-degree angle in the 512(2) matrix showed significant overestimation compared with that in the 1024(2) matrix (0.096 vs. -0.069 mm; p=0.015). There was no difference in accuracy in the 512 x 1024 matrix. Our results suggest that the direction of the vessel against the TV image affects accuracy of measurement in the QCA system.

Coronary Angiography↗