No abstract available.
Densitometry*

No abstract available.
Densitometry* ; Osteoporosis*

PURPOSE: To evaluate the effect of reconstruction algorithms on the CT measurement of mean lung mass density and normal thoracic structures. MATERIALS AND METHODS: Forty-six patients with a 2-9cm-sized lung mass underwent thoracic CT examinations with intravenous contrast enhancement and using a CT HiSpeed Advantage scanner (GE Medical Systems). In each examination, the axial image of the lung mass was reconstructed using soft, standard, detail, and bone algorithms. The mean value and standard deviation of mass density in Hounsfield Units (HU) were measured using ROIs of three different sizes (50 mm2, 200 mm2, and 350 mm2 or more), and the same method was used to measure the density of normal lung, muscle, bone, and vessels. In 21 patients, mass density was also measured on unenhanced and delayed enhanced images and the degree of enhancement was calculated. RESULTS: The average maximum difference in mean mass density in the images of the four different algorithms was less than 1 (range, 0.1 -1.9) HU (ROI size, 350 mm2 or more), 0 -4.2 HU (200 mm 2), and 0.1 -3.6 HU (50mm2). The average maximum difference in the degree of lung mass enhancement was 0.5 -1.2 (range, 0 -1.6 )HU (ROI size, 350 mm2 or more). The mean density of the four normal thoracic structures was highest in images reconstructed with the bone algorithm, though there was no significant difference between the four different algorithms (p = 1.000). CONCLUSION: The measured mean CT density of a lung mass larger than 2 cm does not significantly change according to the reconstruction algorithm used. When using a small ROI, however, the density difference may increase.
Densitometry* ; Humans ; Lung*

PURPOSE: To evaluate the correlation between nuclear density measured using the Pentacam(R) (Oculus Optikgerate GmbH, Wetzlar, Germany) Scheimpflug imaging system and phacoemulsification parameters. METHODS: The nuclear density was measured using maximal nuclear density with ImageJ, Pentacam(R) nucleus staging (PNS), average value and maximal value in lens densitometry. Intraoperatively, effective phaco time (EPT) and balanced salt solution (BSS) used were noted and compared with the nuclear density calculation methods. As an index of corneal endothelial cells, the changes in cell density (CD) were compared with the nuclear density. RESULTS: Regarding EPT, maximal nuclear density with ImageJ (r = 0.379, p < 0.01) and PNS (r = 0.367, p < 0.01) were correlated positively, but the other methods were not correlated. Concerning BSS used, maximal nuclear density with ImageJ (r = 0.279, p = 0.03) and PNS (r = 0.286, p = 0.04) were positively correlated, but the other methods were not correlated. The specular microscopy showed that as the nuclear density increased, the postoperative CD tended to decrease, but without statistical significance. CONCLUSIONS: Preoperative nuclear density measurements using maximal nuclear density with ImageJ or PNS were correlated with phacoemulsification parameters.
Cell Count ; Densitometry ; Endothelial Cells ; Microscopy ; Phacoemulsification*

The Scheimpflug photography was used to evauate objectively changes in lens opacity at a month interval in 143 eyes of 78 patients affected by early cataract. from Dec. 1993 to Dec. 1994. A total of 48 patients were treated daily with 1.5g bendazac-lysine, and 30 patients constituted the control group. We checked visual acuity and analyzed change of lens opacity by using axial densitometry and retroillumination of Scheimpflug photography after Bendaline(R) medication up to 9 months After treatment, improvement or no change of subjective visual acuity was observed in 65 eyes(78.3%) of treated group, whereas decrement in 35 eyes (58.3%) of control group. In the axial densitometry, the nuclear opacity began to improve after 3 months of medication and opacities of lens between anterior supranucleus and posterior capsule were statistically significant improved after 5 months of medication (p<0.05). There's no correlation in the change of opacity area under retroillumination (p>0.05). The result show that bendazac lysine may be effective in improvement of visual acuity and delay the formation of lens opacity in early cataract.
Cataract* ; Densitometry ; Humans ; Lysine ; Photography ; Visual Acuity

OBJECTIVETo determine densities of mineral drugs and their calcined products by using sealing wax densimetry, and to establish the testing method of crispness for calcined traditional Chinese medicine.

METHODTaking density as detection indicator, the accuracies of mineral drugs and their calcined products were investigated by sealing wax densimetry compared with direct densimetry, and the method of density determination was optimized.

RESULTThe density values measured by two methods investigated above were significantly different (P < 0.01), the density values of Pyritum, Haematitum, calcined Pyritum and calcined Haematitum measured by direct densimetry were increased 1.66%, 9.43%, 96.72% and 9.02%, respectively compared with that measured by sealing wax densimetry.

CONCLUSIONSealing wax densimetry is suitable for the density determination of mineral drugs and their calcined products with its high accuracy, whereas direct densimetry'is not suitable for the density determination of mineral drugs and their calcined products.

PURPOSE: To compare the copper equivalent values measured at premolar and molar areas in the copper equivalent images of panoramic and intraoral radiographs and to evaluate the possibility of the copper equivalent images of panorama for the assessment the bone density. MATERIALS AND METHODS: Intraoral radiograms at mandibular premolar and molar area and panoramas of 6 human dry skulls were taken with copper-step wedge by Heliodent MD (Siemens Co., Germany) and by Planmeca (PM 2002 CC, Planmeca, Helsinki, Finland) were used for experiment. The copper equivalent values measured at premolar and molar areas in the copper equivalent im ages of panorama and intraoral film were compared. RESULTS: The copper equivalent values were ranged 0.20 mmCu-0.44 mmCu at the molar areas, 0.05 mmCu-0.31 mmCu at the premolar areas on panoramic images. There were no significant differences (p>0.5) between the copper equivalent values on intraoral images and those on panoramic images measured at premolar areas and molar areas respectively. The correlation coefficient between the copper equivalent values on intraoral images and those on panoramic images was respectively 0.8495 at molar areas and 0.6184 at premolar areas. CONCLUSIONS: The copper equivalent images of panorama for the assessment the bone density appeared to be significant at molar area compared with the one of intraoral radiograph.
Bicuspid ; Bone Density ; Copper ; Densitometry ; Humans ; Molar ; Radiography ; Skull

BACKGROUND: Although dual energy X-ray absorptiometry (DXA) is known to standard equipment for bone mineral density (BMD) measurements. Different results of BMD measurement using a number of different types of devices are difficult to use clinical practice. The purpose of this study was to evaluate discrepancy and standardizations of DXA devices from three manufactures using a European Spine Phantom (ESP). METHODS: We calculated the accuracy and precision of 36 DXA devices from three manufacturers (10 Hologic, 16 Lunar, and 10 Osteosys) using a ESP (semi-anthropomorphic). The ESP was measured 5 times on each equipment without repositioning. Accuracy was assessed by comparing BMD (g/cm2) values measured on each device with the actual value of the phantom. Precision was assessed by the coefficient of variation (CVsd). RESULTS: Lunar devices were, on average, 22%, 8.3%, and 5% overestimation for low (L1) BMD values, medium (L2), and high (L3) BMD values. Hologic devices were, on average, 6% overestimation for L1 BMD, and 5% and 6.2% underestimation for L2 and L3 BMD values. Osteosys devices was, on average, 12.7% (0.063 g/cm2), 6.3% (0.062 g/cm2), and 5% (0.075 g/cm2) underestimation for L1, L2, and L3, respectively. The mean CVsd for L1-L3 BMD were 0.01%, 0.78%, and 2.46% for Lunar, Hologic, and Osteosys devices respectively. CONCLUSIONS: The BMD comparison in this study demonstrates that BMD result of three different devices are significant different between three devices. Differences of BMD between three devices are necessary to BMD standardization.
Absorptiometry, Photon ; Bone Density ; Densitometry* ; Lumbar Vertebrae ; Spine*

The relationship between the serum values of prostate-specific antigen (PSA) and the histologic composition of benign prostatic hyperplasia (BPH) was investigated in 32 symptomatic BPH patients undergoing transurethral resection of the prostate. We evaluated the free and total PSA concentrations by ACS-PSA2 (Ciba-Corning) assay. The stereological analysis was made by computer aided-area densitometry using H & E stained slides to quantify stromal and glandular areas in the resected prostate tissue. The total PSA concentration versus percentage of glandular area (%G) and stromal-glandular ratio (SGR) correlated significantly (p<0.05 for both) whereas the free PSA concentration and free/total PSA ratio did not (p>0.05 for both). These data suggest that total PSA is directly correlated with the histologic composition of the prostate in men with BPH, however, the proportion of free to total PSA was not informative to predict the histology. Thus, pretreatment evaluation of total PSA would be useful as part of an evaluation method of BPH for medical therapy.
Densitometry ; Humans ; Male ; Prostate ; Prostate-Specific Antigen* ; Prostatic Hyperplasia*

We developed a new method for an objective assessment of the meconium content in amniotic fluid. By establishing a standard scale through a serial dilution of a known amount of meconium into the amniotic fluid, we developed a new method 'mecometer 'that can objectively measure the meconium content in meconium-stained amniotic fluid samples. The objectivity and reliability of this mecometer were verified by 300 student volunteers. At least 70% of the volunteers could objectively measure and digitally describe the meconium content in meconium-stained amniotic fluid samples. We believe our newly developed mecometer is a very simple, reliable, and portable method, not requiring any instruments.
Amniotic Fluid/*metabolism ; Densitometry/methods ; Humans ; Infant, Newborn ; Meconium/*metabolism