[Experiences with a point evaluation system for the quantitative evaluation of performance in the medical laboratory].
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Germany, East↗
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Is one testicular specimen sufficient for quantitative evaluation of spermatogenesis?
OBJECTIVE: To investigate whether quantitative analysis performed on one testicular specimen is adequate for quantitative evaluation of spermatogenic process. DESIGN: Comparison of quantitative analysis of spermatogenic cell types in testicular cytologic aspirates of various sites of each testis. SETTING: In each aspirate, a total of 500 Sertoli cells and cells at each of the spermatogenic stages were identified, counted, and grouped according to cell type. A quantitative cell type index was calculated for each type of cell in each aspirate. Mean cell type indexes then were calculated for each of the cell types in the three aspirates of each patient, and variations of a given sample from its mean were compared. PATIENTS: Azoospermic or severely oligospermic infertile men. INTERVENTIONS: Fine needle aspiration performed on the upper, middle, and lower poles of each testis. RESULTS: Each of the aspirates showed wide deviations from the mean of the three aspirates for that patient. The deviation ranges of the cell type indexes of each of the spermatogenic stages were as follows: spermatogonia, 0.8% to 200%; spermatocytes, 1.4% to 94.3%; spermatids, 2.9% to 200%; and spermatozoa, 0.7% to 128%. In the majority of the patients, at least one of the three aspirates showed a cell type index score that was statistically different from the others. CONCLUSIONS: These results suggest that more than one testicular specimen is needed to evaluate quantitatively the spermatogenic process.
Biopsy, Needle↗
Quantitative evaluation of axial wall taper in prepared artificial teeth.
The purpose of this study was to quantitatively evaluate the axial wall taper of prepared artificial teeth using a non-contact three-dimensional shape measuring system. A total of 54 artificial teeth prepared by pre-clinical dental students for complete cast restorations were evaluated. For quantitative analysis, five cross sections were computer-graphically placed perpendicularly to the z-axis. The surface coordinate values (x, y, z) of each cross section were converted into polar coordinate values (r, theta), which were then graphically rendered to a two-dimensional plane. At four points, each 90 degrees from the distal center point of the cross section, the axial wall taper was quantitatively calculated using a formula based on the differences in radius between the highest and lowest positions of the cross sections of the prepared tooth. The average calculated taper was 5.8 degrees in the distal region, 21.7 degrees in the buccal region, 14.9 degrees in the mesial region and 12.5 degrees in the lingual region. These results suggest that the axial wall taper of prepared teeth can be quantitatively evaluated using this measuring system.
Computer Graphics↗
Fractal analysis for quantitative evaluation of diffuse lung abnormalities on chest radiographs: use of sub-ROIs.
We evaluated the usefulness of fractal analysis for quantitative evaluation of diffuse lung abnormalities seen on chest radiographs. Regions of interest (ROIs) with 296 x 296 matrix size were selected in the right upper and lower lung zones of digitized chest radiographs. We selected ROIs of 50 mild and 50 severe diffuse lung abnormalities and 50 ROIs of normal lungs. The fractal dimension (FD) for each ROI was defined as the mean value of those obtained from sub-ROIs in each ROI. In the sub-ROIs with 256 x 256, 128 x 128, and 64 x 64 matrix size, the mean values of FDs obtained from the patients with diffuse lung abnormalities were significantly higher than those obtained from the patients with normal lungs (P < 0.001, respectively). The performance of FDs obtained from the sub-ROIs with 256 x 256 matrix size was equal to that obtained from the sub-ROIs with 128 x 128 matrix size (P = 0.980). However, the performance of FDs obtained from the sub-ROIs with 128 x 128 matrix size was superior to that obtained from the sub-ROIs with 64 x 64 matrix size (P = 0.0001). Fractal analysis is useful for quantitative evaluation of diffuse lung abnormalities seen on chest radiographs. From our results, the sub-ROIs whose matrix sizes were greater than or equal to 128 x 128 were suggested to be suitable for quantitative evaluation of diffuse lung abnormalities seen on chest radiographs.
Fractals↗
[Measurement of cerebral blood volume by reflections spectrophotometry: methodological improvement and quantitative evaluation].
The authors described methodological improvement and quantitative evaluation in measurement of cerebral blood volume (CBV) by reflectance spectrophotometry. The measurement of blood volume by this method has not been applied to the brain tissue because of the methodological difficulties. In order to obtain the accurate CBV values with this method, it is necessary to keep the proper contact between the sensor for the measurement and the brain tissue to be measured. For this purpose we developed a balance arm. A sensor for CBV measurement was fixed with the one side of the arm and a weight was installed to the other side. The pressure of the sensor to the brain can be adjusted by moving the weight, and the sensor was placed on the brain tissue with the proper pressure. Moreover, the sensor was attached with an acryl-made cap to make the pressure adjustment easier by enlarging the contact surface and to enable to observe the vasculature on the surface of the brain. With this improved method the reasonable changes of CBV could be obtained when the CO2 gas was inhalated and cerebral ischemia was produced in cats. The possibility of the quantitative evaluation was investigated using the homogenized brain tissue of cats. After the elimination of the blood from the brain by the perfusion with the saline, the brain was removed and homogenized. Then, the definite volume of blood, of which hemoglobin volume was already known, was added and measured by this method.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
[Quantitative evaluation of 111In-antimyosin Fab myocardial imaging in acute myocardial infarction patients].
Quantitative evaluation of 111In-antimyosin Fab myocardial (InAM) imaging was performed in 15 patients with acute myocardial infarction to evaluate which organ is the most appropriate for the control of myocardial accumulation, to compare the quantitative method with the conventional visual method, and to study which clinical indices correlate with the InAM quantitative evaluations. InAM images demonstrated the myocardium with 31 +/- 6 mean counts/pixel, lung with 14 +/- 4, upper mediastinum with 20 +/- 5, middle mediastinum with 26 +/- 5, and liver with 75 +/- 10. We considered the lung to be the most appropriate control organ for quantitative evaluations of InAM imaging, because it could be separated from the myocardium, and the measurement range was narrow. The InAM uptake index [IUI = (myocardial counts-lung counts)/lung counts] was calculated as the index of myocardial accumulation. Visual evaluations of myocardial accumulation on InAM images were classified into three grades. The IUI of grade 1 (slight) was 0.98 +/- 0.19, grade 2 (moderate) was 1.34 +/- 0.38, and grade 3 (severe) was 1.97 +/- 0.19. Visual grading was nearly in accordance with the IUI, although it was difficult to distinguish visually between grades 1 and 2. Measurement of wall motion by left ventriculography showed that reduced wall motion was associated with an IUI of 1.01 +/- 0.18 and dyskinesis with an IUI of 1.92 +/- 0.16, showing IUI can indicate regional myocardial damage. However, IUI was not correlated with indices of the overall left ventricular function, such as ejection fraction, cardiac index, and peak creatine kinase level.
Antibodies, Monoclonal↗
Minimum sample size of kidney biopsies for semiquantitative and quantitative evaluation.
The minimum sample size for semiquantitative and quantitative evaluation of interstitial tubular and glomerular parameters is calculated. For the majority of parameters a renal cortex area of 2 mm2 or 7 glomeruli (adults) or 13 glomeruli (children) is sufficient. Larger biopsies or more glomeruli are necessary for the evaluation of the area density of interstitium patent and obsolescent glomeruli as well as the numerical density of obsolescent glomeruli. The most sensitive parameters are those concerning crescents which require biopsies of 11-19 glomeruli in adults and 40 glomeruli in children. In summary, biopsies of usual size (10 mm2) containing about 20 glomeruli are sufficient for qualitative and quantitative evaluation.
Adolescent↗
Method for quantitatively evaluating the lateralization of linguistic function using functional MR imaging.
BACKGROUND AND PURPOSE: Various methods for evaluating the lateralization of linguistic function using functional MR imaging have been proposed. However, the optimal method remains controversial. The purpose of this study was not only to establish a method for quantitatively evaluating the lateralization of linguistic function but also to evaluate its optimality. METHODS: Internal speech tasks were measured by functional MR imaging in 17 healthy adult volunteers by use of z scores. The laterality index (LI) was calculated first by a previously reported method and second by our newly designed method, in which we investigated the correlation between the z scores and the number of activated pixels in the regions of interest; that is, we made scatter diagrams (z scores versus number of activated pixels). To obtain detailed information, we searched a regression function that fit the scatter diagrams well. RESULTS: We found the number of activated pixels was proportional to (1/z score)(4) and the correlation coefficient was very high. Each hemisphere showed an original proportional constant. Our newly designed LI was calculated from these two constants and was found to be a fixed value. In contrast, the reported LI varied with the z score. We found our LI differed in robustness and reproducibility from the reported LI. CONCLUSION: Our LI method proved more optimal than the reported LI. The lateralization of linguistic function can be evaluated quantitatively using our new LI method.
Adult↗
[A comparative study of imaging of myocardial perfusion with 201Tl-SPECT and 13NH3-PET: visual and quantitative evaluation].
UNLABELLED: We compared the results of visual and quantitative evaluation of imaging of myocardial perfusion with 201Tl-SPECT and 13NH3-PET in the 7 non-myocardial infarction (non-MI) and 42 myocardial infarction (MI) patients. On the 201Tl-SPECT and 13NH3-PET imaging, the degree of accumulation of each radioisotope (RI) was visually classified into four grades of defect score. The percentage of uptake was also quantitatively evaluated. RESULTS: In the 7 non-MI patients, NH3% uptake in the lateral wall was significantly lower than in the septum, and in the lateral wall NH3% uptake was significantly lower than Tl% uptake. For the 42 MI patients, segmental defect scores (DS) on 201Tl-SPECT were compared with those on 13NH3-PET, and a high degree of concordance in DS was found for all territories of the left ventricle, antero-septum MI and inferior MI territories. Average Tl% uptake/NH3% uptake was near 1, a highly positive correlation was found between Tl% uptake and NH3% uptake in all territories of the left ventricle and antero-septum MI territories, and Tl% uptake/NH3% uptake was larger than 1, but, a significant positive correlation existed between Tl% uptake and NH3% uptake in the territory with inferior MI. CONCLUSION: These findings indicate that results of 201Tl-SPECT imaging were similar to those of 13NH3-PET in evaluation of myocardial perfusion in the antero-septum and inferior. However, a difference in distribution was observed between 201TlCl and 13NH3 in the lateral wall, indicating that particular attention should be paid to the results of imaging of myocardial perfusion in the lateral wall.
Aged↗
[Implementation of receiver operating characteristics for the quantitative evaluation of stereotactic radiotherapy treatment plans].
The definition of criteria and of a methodology dedicated to the quantitative evaluation of conformal stereotactic treatment plans is presented. We implemented the 'Receiver Operating Characteristics' (ROC) analysis, already used in medical imaging, for the quantitative evaluation of irradiation treatment plans. This implementation is based on data provided by dose-volume histograms (DVH). Three techniques, each one using a different dosimetric criterion, were defined for the choice of a reference isodose for a given treatment plan. We used this ROC analysis for the selection of the most conformal treatment plan and its reference isodose among the treatment plans proposed for one patient. This study revealed the interest of ROC analysis based on dose-volume histograms for the quantitative evaluation of treatment plans.
Humans↗
Skeletal muscle ultrasonography: Visual versus quantitative evaluation.
In this study, we compared the sensitivity and specificity of visual versus quantitative evaluation of skeletal muscle ultrasound in children suspected of having a neuromuscular disorder (NMD). Ultrasonography (US) scans of four muscles (biceps brachii, forearm flexors, quadriceps femoris, anterior tibial muscle) were made in 76 children. All images were visually evaluated using the Heckmatt criteria and quantitatively evaluated with computer-assisted grey-scale analysis of muscle echo intensity. Visual evaluation could achieve a sensitivity up to 71%, with a specificity of 92%. With quantification, a sensitivity of 87% accompanied by a specificity of 67% was found, but other diagnostic values could be achieved, depending on the cut-off point. Quantification resulted in a higher interobserver agreement (kappa 0.86) compared with visual evaluation (kappa 0.53). We conclude that quantification of echo intensity is a more objective and accurate method. Because it can achieve higher sensitivities, it is better-suited for the screening task in the diagnostic phase of children with a NMD.
Adolescent↗
Quantitative evaluation by Tl-201 scintigraphy in the diagnosis of thyroid follicular nodules.
We examined the diagnostic capability of a quantitative evaluation by determining the optimum area for comparisons with nodule and optimum imaging time by Tl-201 scintigraphy in thyroid follicular nodules, retrospectively. Ninety-one thyroid follicular nodules, for which the pathological diagnosis had been established, were examined (60 benign, 31 malignant). After 74 MBq of Tl-201 chloride was injected intravenously, Tl-201 scintigrams were obtained at 10, 20, 30, and 120 min. For the quantitative evaluation, the area with the greatest accumulation in the nodule and a comparative region in the contralateral thyroid and the soft tissues in the cervical region were manually selected as the region of interest (ROI) referring to Tc-99m pertechnetate scintigrams and ultrasonographic findings as a guide by two radiologists, and the T/N ratio (tumor/normal tissue ratio) and T/S ratio (tumor/soft tissue ratio) were calculated. The pixel counts were determined for all ROI. A summary index of overall test performance can be calculated as the area under the receiver operating characteristic (ROC) curve (Area (Az)), and the likelihood ratios were also calculated. We estimated the cut-off on a fitted binormal ROC curve. Multiple regression analyses were used to investigate the relationships between the optimum quantitative evaluation and 5 independent variables. A p value below 5% was considered to be significant. The T/N ratio and T/S ratio were significantly higher in the malignant group at 10 min (0.844 and 0.702), 20 min (0.844 and 0.704), 30 min (0.841 and 0.670), and 120 min (0.887 and 0.733), respectively (p < 0.01). The Az for the T/N ratio was greatest at 120 min. The multiple regression analysis showed that only 'benign or malignant' was a significant variable in the T/N ratio at 120 min. It correlated significantly in interobserver (r = 0.80) and intraobserver (r = 0.80) studied (p < 0.001). An assessment of the cut-off value of the T/N ratio at 120 min, at the cut-off of 1.255, the likelihood ratio for positive test result was greatest at 8.56, while at the cut-off of 1.010, the likelihood ratio for negative test result was lowest at 0.165. The T/N ratio at 120 min was more useful than the other condition to distinguish between benign and malignant thyroid follicular nodules.
Adenocarcinoma, Follicular↗
[To develop a model on severe acute respiratory syndrome epidemics to quantitatively evaluate the effectiveness of intervention measures].
OBJECTIVE: To build an epidemic model of severe acute respiratory syndrome (SARS) to be used to quantitatively evaluate the effectiveness of intervention measures. METHODS: Following the nature of SARS epidemics, an epidemic model of SARS based on SEIR model of infectious disease was built, in which case management group was set up and some parameters related to control measures were included. As an example, data gathered from Beijing was fitted to illustrate its application to quantitatively evaluate the intervention measures. RESULTS: In the newly developed model of epidemics, parameters related to control measures could easily be modified. When scenario assumption was used, a model on SARS outbreak under various circumstances of intervention measures could be set. Thus, quantitative evaluation of intervention measures could perfectly be caried out. Pilot study revealed that the fitness existed in modeling the outbreak of SARS in Beijing and the intervention measures implemented around April 20, 2003, had major contribution to the control of SARS. CONCLUSION: The model of SARS epidemics seemed to be stable and reliable to be used to evaluate the effectiveness of intervention measures implemented during the SARS outbreak in a quantitative way.
China↗
Quantitative evaluation of 99mTc-hexamethylpropylenamineoxime brain SPECT in childhood-onset epilepsy.
In 10 patients with childhood-onset epilepsy, quantitative evaluation (QE) of interictal regional cerebral blood flow (rCBF) using technetium-99m-hexamethylpropylenamine oxime (99mTc HMPAO) single-photon emission computed tomography (SPECT) was correlated with seizure foci localized by electroencephalography (EEG). Eighty regions of interest (5 x 5 pixels) were placed at five different neocortical areas in both cerebral hemispheres, in coronal and transaxial planes. Mean counts/pixel were calculated for each region and multiple right-left comparisons were done. Quantitative evaluation of 99mTc-HMPAO increased detection of rCBF abnormalities by 26%. Abnormal EEG patterns correlated with abnormal rCBF in 75% of cases (Phi = 0.788, p < 0.001), and with visually detected abnormalities in 50% (Phi = 0.493, p < 0.001). Discordance between EEG and SPECT was most frequent in patients with non-localizing EEG (n = 3). In childhood-onset epilepsy, quantitative evaluation of brain perfusion scans provides: (a) objective estimates of interictal rCBF; (b) more precise detection of epileptogenic foci, when used to complement EEG.
Adolescent↗
Quantitative evaluation of acquisition parameters in three-dimensional imaging with multidetector computed tomography using human skull phantom.
This study evaluated the quantitative measurements of three-dimensional (3D) volume images using multidetector row computed tomography (MDCT) and one skull specimen. Twenty-one linear distances were measured five times each by vernier caliper. A dry human skull was imaged with MDCT for various acquisition parameters at slice thicknesses of 1.25, 2.50, 3.75, and 5.00 mm for the different acquisition modes of axial and spiral scan. The distance of each corresponding item displayed on 3D rendered images was measured seven times by an uninvolved observer using a 3D software tool. Data analysis was performed to determine if there were any statistically significant differences in acquisition parameters. No significant image differences were found among the scan modes for each slice thickness. For a given scan mode, acquisition slice thickness was the important factor for quantitative measurement of 3D rendered CT images.
Humans↗
Quantitative evaluation of inflammation in biopsy specimens from idiopathically failing or irritable hearts: experience in 80 pediatric and adult patients.
The histologic criteria for the diagnosis of myocarditis on an endomyocardial biopsy specimen are troubled by varying institutional criteria and interobserver differences. A comprehensive approach to tissue evaluation including quantitative assessment of mononuclear cell populations enhances the accuracy and the specificity of the morphologic diagnosis. Future efforts to characterize the infiltrating cell lines in inflammatory conditions of the heart will aid in the ultimate refinement of therapeutic efficacy.
Adult↗
Quantitative evaluation of urinary porphyrins as a measure of kidney mercury content and mercury body burden during prolonged methylmercury exposure in rats.
Changes in urinary porphyrin excretion patterns (porphyrin profiles) during prolonged mercury exposure are attributable to mercury accumulation in the kidney and to consequent effects of Hg2+ on renal porphyrin metabolism. In the present study, we evaluated the quantitative relationship of urinary porphyrin concentrations to mobilizable renal mercury content, using the metal chelator 2,3-dimercapto-1-propanesulfonic acid (DMPS) to modulate kidney mercury levels. Rats exposed to methylmercury hydroxide (MMH) at 10 ppm in drinking water for 6 weeks were treated with up to 3 consecutive doses of DMPS (100mg/kg, ip) at 72-h intervals. Consistent with previous findings, the concentrations of pentacarboxyl- (5-) and copro- (4-) porphyrins and of an atypical porphyrin specific to mercury exposure, precoproporphyrin, were significantly elevated in urine of MMH-exposed rats, compared with that of rats exposed to distilled water (dH2O) for the same period. Consecutive DMPS treatments of MMH-exposed rats significantly decreased kidney concentrations of total, as well as Hg2+ and CH3Hg+ species, and promoted increased urinary mercury excretion. Concomitantly, DMPS treatment decreased both kidney and urinary porphyrin concentrations, consistent with depletion of renal mercury levels. Regression analyses demonstrated a high correlation (r approximately 0.9) between prechelation urinary porphyrins and postchelation urinary mercury levels and also between prechelation urinary porphyrins and prechelation kidney mercury concentrations. These findings demonstrate that urinary porphyrin concentrations relate quantitatively to DMPS-mobilizable mercury in the kidney and, therefore, serve as a biochemical measure of renal mercury content.
Animals↗
Quantitative evaluation of sialograms.
RATIONALE AND OBJECTIVES: The authors developed and evaluated a quantitative analytic method for interpreting clinical sialograms. METHODS: Images were obtained by digital subtraction sialography and transformed into binary form. The duct width of the image was calculated and represented as a normalized histogram. The effects of the volume of contrast medium injected and of the inclination angle of the objects on the histogram were examined. RESULTS: In model studies, the normalized histogram was affected insignificantly by these factors. Clinical sialograms of 18 patients with normal results, 12 patients with parotitis, and 5 patients with Sjögren syndrome were preliminarily analyzed by the histogram method and four representative parameters of the histogram. Discriminant analysis showed a relatively high correct-predictive rate in the distinction between patients with normal and abnormal results. CONCLUSIONS: This method reduces the effect of observer variation in diagnosing sialograms, and improves diagnostic accuracy for assessing the presence of inflammatory diseases of the parotid gland.
Animals↗