Eldecalcitol is superior to alfacalcidol in maintaining bone mineral density in glucocorticoid-induced osteoporosis patients (e-GLORIA)

INTRODUCTION

Eldecalcitol increases bone mineral density (BMD) and reduces vertebral fracture in patients with primary osteoporosis. However, the effect of eldecalcitol on BMD and fracture in glucocorticoid-induced osteoporosis (GIO) patients is unknown. This study was undertaken to compare the effect of eldecalcitol on BMD and fracture with that of alfacalcidol in GIO patients.

MATERIALS AND METHODS

A randomized, open-label, parallel group study was conducted to identify the effectiveness and safety of monotherapy with 0.75 μg eldecalcitol compared with 1.0 μg alfacalcidol in GIO patients.

RESULTS

Lumbar spine BMD increased with eldecalcitol, but decreased with alfacalcidol at 12 and 24 months (between group difference 1.29%, p < 0.01, and 1.10%, p < 0.05, respectively). Total hip and femoral neck BMD were maintained until 24 months by eldecalcitol, but decreased by alfacalcidol (between group difference 0.97%, p < 0.05 and 1.22%, p < 0.05, respectively). Both bone formation and resorption markers were more strongly suppressed by eldecalcitol than by alfacalcidol. Eldecalcitol showed better effect on BMD than alfacalcidol in patients with no prevalent fracture and BMD > 70% of the young adult mean, and with ≤ 3 months of previous glucocorticoid treatment. No significant difference in the incidence of vertebral fracture was found, and the incidence of adverse events was similar between the two groups.

CONCLUSIONS

Eldecalcitol was more effective than alfacalcidol in maintaining BMD in GIO patients. Because eldecalcitol was effective in patients with no or short-term previous glucocorticoid treatment, as well as those without prevalent fracture or low BMD, eldecalcitol can be a good candidate for primary prevention of GIO.

CLINICAL TRIAL REGISTRATION NUMBER

UMIN000011700.

Efficacy of combined treatment with alendronate (ALN) and eldecalcitol, a new active vitamin D analog, compared to that of concomitant ALN, vitamin D plus calcium treatment in Japanese patients with primary osteoporosis

Combined treatment with alendronate and eldecalcitol was found to be more effective in reducing the bone turnover markers and increasing bone mineral density than alendronate treatment with vitamin D3 and calcium supplementation in the osteoporotic patients.

INTRODUCTION

We compared the clinical efficacy and safety of combined treatment with alendronate plus eldecalcitol (ALN + ELD) with those of treatment with ALN plus vitamin D and calcium (ALN + VitD).

METHODS

Osteoporotic 219 patients were randomly assigned to the ALN + ELD, or the ALN + VitD group. Primary endpoint was the inter-group differences in lumbar spine BMD (L-BMD) at patient's last visit. Secondary endpoints included the differences in BMD at other sites and the bone turnover marker (BTM) levels.

RESULTS

L-BMD, total hip BMD and femoral neck (FN-BMD) increased from baseline by 7.30, 2.41, and 2.70 % in the ALN + ELD group, and by 6.52, 2.27, and 1.18% in the ALN + VitD group, respectively. Inter-group differences of the L-BMD and total hip BMD values were not significant. The increase of the FN-BMD was larger in the ALN + ELD group than the ALN + VitD group. Reductions of the BTMs were greater in the ALN + ELD group than the ALN + VitD group. Interaction of the percent increase of the L-BMD with the baseline values of the BTMs was observed in the ALN + VitD group only. The increases of the FN-BMD in patients with lower baseline values of type-I-collagen C-telopeptide (sCTX) and serum 25(OH) D levels <20 ng/mL were significantly larger in the ALN + ELD group than the other group.

CONCLUSION

Combination treatment of ALN plus ELD was more effective in reducing the BTMs and increasing the FN-BMD than ALN treatment with vitamin D3 and calcium.

The effects of once-weekly teriparatide on hip geometry assessed by hip structural analysis in postmenopausal osteoporotic women with high fracture risk

Weekly administration of teriparatide has been shown to reduce the risk of vertebral and non-vertebral fractures in patients with osteoporosis at higher fracture risk in Japan. However, its efficacy for hip fracture has not been established. To gain insight into the effect of weekly teriparatide on the hip, hip structural analysis (HSA) based on dual-energy X-ray absorptiometry (DXA) was performed using the data of 209 postmenopausal osteoporotic women who had participated in the original randomized, multicenter, double-blind, placebo-controlled trial assessing the effects of once-weekly 56.5 μg teriparatide for 72 weeks. The DXA scans, obtained at baseline, 48 weeks and 72 weeks, were analyzed to extract bone mineral density (BMD) and cross-sectional geometrical indices at the narrowest point on the neck (NN), the intertrochanteric region (IT), and the proximal shaft. Compared with placebo after 72 weeks, the teriparatide group showed significantly higher BMD, average cortical thickness, bone cross-sectional area, and section modulus, and lower buckling ratio at both the NN and IT regions. No significant expansion of periosteal diameter was observed at these regions. There were no significant differences in BMD and HSA indices at the shaft region. The results indicate that overall structural strength in the proximal femur increased compared to placebo, suggesting that once-weekly teriparatide effectively reverses changes in hip geometry and strength with aging.

Effect of the cathepsin K inhibitor odanacatib administered once weekly on bone mineral density in Japanese patients with osteoporosis--a double-blind, randomized, dose-finding study

The efficacy and safety of oral placebo or odanacatib 10, 25, or 50 mg once weekly for 52 weeks were evaluated in a double-blind, randomized, multi-center study in Japanese female and male patients with osteoporosis.

INTRODUCTION

Odanacatib is a selective and reversible cathepsin K inhibitor that decreases bone resorption and increases bone mineral density (BMD).

METHODS

The primary efficacy endpoint was percent change from baseline to week 52 in lumbar spine BMD. Secondary endpoints included percent change in total hip, femoral neck, and trochanter BMD and in bone biomarkers after treatment for 52 weeks.

RESULTS

In this study, 286 patients [94% female, mean age (SD) 68.2 (7.1) years] were included in the analysis. The least-squares mean percent changes from baseline to week 52 in the groups receiving placebo, 10, 25 and 50 mg of odanacatib for lumbar spine (L1~L4) BMD were 0.5, 4.1, 5.7, and 5.9% and for total hip BMD were -0.4, 1.3, 1.8, and 2.7%, respectively. The changes in femoral neck and trochanter BMD were similar to those at the total hip. Bone turnover markers were reduced in a dose-dependent manner. However, the effects of odanacatib on bone formation markers were less compared with the effects on bone resorption markers. Tolerability and safety profiles were similar among all treatment groups with no dose-related trends in any adverse events.

CONCLUSIONS

Weekly odanacatib treatment for 52 weeks increased BMD at the lumbar spine and at all hip sites in a dose-dependent manner and was well tolerated in Japanese patients with osteoporosis.

Hip structural analysis: a comparison of DXA with CT in postmenopausal Japanese women

Geometry of the proximal femur is one determinant of fracture risk, and can be analyzed by a simple method using dual-energy X-ray absorptiometry (DXA). The aim of the present study was to investigate the accuracy of hip structural analysis (HSA) using clinical data in postmenopausal Japanese women. A total of 184 postmenopausal women aged 51–88 years (mean, 70.5 ± 8.7 years) who underwent artificial joint replacement surgery for osteoarthrosis of the hip or knee joint were included. Computed tomography (CT) data from preoperative assessment were utilized for analysis of proximal femoral geometry (CT-HSA) using QCTPro Software (Mindways Software Inc., Austin, TX) and compared with HSA results based on DXA (DXA-HSA). The results of femoral geometry were further compared with a CT-based finite-element method (CT/FEM). There was moderate to high correlation between DXA-HSA and CT-HSA (r=0.60-0.90, p<0.001), except for the buckling ratio in the intertrochanteric region. Moreover, the correlation of HSA with CT/FEM was similar between DXA-HSA and CT-HSA. The present results suggest that the geometry of proximal femoral cross sections can be reasonably well characterized using DXA.

Diagnostic criteria for primary osteoporosis: year 2012 revision

In 1995, the Japanese Society for Bone and Mineral Metabolism (now the Japanese Society for Bone and Mineral Research) established the Osteoporosis Diagnostic Criteria Review Committee. Following discussion held at the 13th scientific meeting of the Society in 1996, the Committee, with the consensus of its members, proposed diagnostic criteria for primary osteoporosis. The Committee revised those criteria in 1998 and again in 2000. The Japanese Society for Bone and Mineral Research and Japan Osteoporosis Society Joint Review Committee for the Revision of the Diagnostic Criteria for Primary Osteoporosis aimed at obtaining international consistency and made a revised edition based on the new findings in 2012.

[Assessment of the exposure dose value displayed on operator console in a computed tomography system deciding exposure dose from positioning image]

The aim of this study was to assess the exposure dose value (DLP) displayed on the operator console in a computed tomography system with automatic exposure control (CT-AEC) which decides the exposure dose from a positioning image. We measured exposure dose with two kinds of CT systems and evaluated the error of the displayed DLP value on the operator console against the measured DLP value. The assessment was performed in three sites: head and neck, upper chest, and lower abdomen. As a result, the errors of displayed value with CT-AEC against the error without CT-AEC in system A (4.09%) were significantly different on two assessment sites (head and neck: -4.02%, upper chest: 6.60%). There is no significant difference on the third assessment site (lower abdomen: 0.06%). On the other hand, those values in system B (8.38%) were almost similar with no significant differences (head and neck: -1.12%, upper chest: -1.85%, lower abdomen: -0.64%). The results show that there were significant differences noted between the errors of displayed value with CT-AEC and without CT-AEC in system A for the head and neck and the upper chest. In conclusion, displayed value with CT-AEC and without CT-AEC were about the same error. However, the possibility that the error depended on a model and the examination site of CT was shown.

[Study of the additional filter in transcatheter hepatic arterial embolization]

It is well known that Interventional Radiology (IVR) is useful. However, the patient dose in IVR is increasing because of the prolongation of fluoroscopic time and the increase in the number of radiographies in recent years. We studied the adequacy of the additional filter for the decrease of the skin surface dose in patients with hepatocellular carcinoma of transcatheter arterial embolization (TAE). In 20 patients (15 men and 5 women, average age: 66.9 and 72.0 years old) who had undergone TAE, we estimated the skin surface dose from the records of their exposure condition (tube voltage, tube current, time, and field size of image intensifier) and the results of the phantom experiment with 2 kinds of additional filter. The estimated skin surface dose of the patient was 1.75 ± 0.84 with the additional filter of 1.5 mm thickness of aluminum (1.5 mmAl), 1.46 ± 0.67 Gy with 0.03 mm thickness tantalum (0.03 mmTa) and 1.17 ± 0.55 Gy with 0.06 mm thickness of tantalum (0.06 mmTa). Against a skin surface dose of 1.5 mmAl, the dose reduction of 16.7% was shown in 0.03 mmTa and 33.2% in 0.06 mmTa. With a DSA phantom of iodine density 0.5 and 1.0 and 2.0 mgI/ml, DSA images were acquisitioned at tube voltage 70, 80 and 90 kV to compare the detectability of contrast media in 0.06 mmTa with 1.5 mmAl. To evaluate the detectability of contrast media in 0.06 mmTa in 1.5 mmAl, receiver operating characteristic (ROC) analysis was performed with the pixel value of the phantom image. The area under the ROC curve in a 1.5 mmAl filter and the 0.06 mmTa filter provided with each contrast media density and each tube voltage was approximately a constant value. It was suggested that there was no differences in the detectability of contrast media in both additional filters. In conclusion, the skin surface dose of the patient was able to be reduced 33.2% without decreasing contrast media detectability by changing the additional filter from 1.5 mmAl to 0.06 mmTa. It was most suitable in TAE in our hospital to choose 0.06 mmTa as an additional filter.

[Method of calculating patient skin surface dose in transcatheter arterial embolization]

The usefulness of interventional radiology (IVR) in clinical practice is well known. However, patient dose in IVR has recently been increased as a result of the prolongation of fluoroscopic time and the increased number of radiographies. We studied a simple method of calculating skin surface dose in patients who underwent transcatheter arterial embolization (TAE) for the treatment of hepatocellular carcinoma by obtaining the value of a dose area product meter attached to the digital subtraction angiography system. In 20 subjects (15 men and 5 women, aged an average of 68.2+/-7.3 years, respectively) who underwent TAE, exposure conditions (tube voltage, tube current, time, and size of image intensifier) in a time series and last value indicated on the dose area product meter were recorded. A dosimetric phantom was placed at a position the same as that of the patient for TAE, the surface dose (SD) of the phantom was measured under various exposure conditions, and SD per unit mAs (SD/mAs) was obtained. Then the skin surface dose in each subject was estimated from the values of the exposure condition and SD/mAs. A high correlation was observed between the last value (x) on the dose area product meter and the estimated skin surface dose (y) (r=0.933), and the following regression equation was derived: y=0.005x-0.589. The skin surface dose calculated using the regression equation was compared with that obtained by the method recommended by the Japan Association on Radiological Protection in Medicine (JARPM), considering the value estimated from the value of exposure conditions with SD/mAs as the gold standard. The results indicated that the error in the method using the regression equation was significantly lower than that of the JARPM method (18.3+/-14.0% and 75.5+/-66.0%, respectively, p<0.01). In conclusion, the skin surface dose in TAE could be monitored with high precision using the value of the dose area product meter by obtaining the regression formula between the value of the dose area product meter and the skin surface dose estimated with the phantom values.

[Study on the accuracy of regional cerebral blood flow measurement using N-isopropyl-p-[123I]iodoamphetamine: effects of differences in venous sampling site and static imaging direction in one-point venous sampling method based on the causality model]

PURPOSE

We have previously reported the method of regional cerebral blood flow measurement using N-isopropyl-p-[123I]iodoamphetamine, in which the input function into brain was estimated from one-point venous blood sampling value based on the method of causality analysis between input and output functions. In the present study, we examined the effects of differences in blood sampling site and direction of static image collection on the accuracy of estimating input function using this method.

METHODS

The subjects consisted of 50 patients of right forearm venous sampling and 50 patients of left forearm venous sampling. As the static imaging directions, the following four combinations were compared 10 all four directions, 2) anterior and posterior directions, 3) right and left directions, and 4) an anterior direction. The accuracy of measurement was evaluated by comparing the estimated and directly measured value of input/output function (Caoct/Cvoct), and by the error indices and the correlation coefficients between the estimated and directly measured value.

RESULT

In both groups of venous sampling, there was no significant difference between the estimated and directly measured value of Caoct/Cvoct. The error indices and correlation coefficient showed no significant difference between the right and left venous sampling groups. Similarly, no significant influence on Caoct/Cvoct value was observed by the difference of static imaging direction. Finally, the rCBF values calculated using these estimations were not significantly different from those by continuous arterial sampling method.

CONCLUSIONS

These results indicate that both the difference in venous sampling site and the static imaging direction have little effect on the accuracy in our new method of rCBF measurement, and suggest its clinical versatility.

Measurement of regional cerebral blood flow with123I-IMP using one-point venous blood sampling and causality analysis: Evaluation by comparison with conventional continuous arterial blood sampling

OBJECTIVE

Arterial input function represents the delivery of intravascular tracer to the brain. The optimal setting of this function is essential for measuring regional cerebral blood flow (rCBF) based on the microsphere model using N-isopropyl-4-[123I]iodoamphetamine (123I-IMP), in which the arterial 123I-IMP concentration (integral value) during the initial 5 min is usually applied. We developed a novel method in which the arterial 123I-IMP concentration is estimated from that in venous blood samples.

METHODS

Brain perfusion SPECT with 123I-IMP was performed in 110 patients with disorders of the central nervous system. A causality analysis determined the relationship between various SPECT parameters and the ratio of the octanol-extracted arterial radioactivity concentration during the first 5 min (Caoct) to the octanol-extracted venous radioactivity concentration at 27 min after an intravenous injection of 123I-IMP (Cvoct). The Caoct/Cvoct value was estimated using various SPECT parameters and compared with the directly measured value.

RESULTS

The measured and estimated values of Caoct/ Cvoct (r = 0.856, n = 50) closely correlated when the following 7 parameters were included in the regression formula: radioactivity concentration in venous blood sampled at 27 min (Cv), Cvoct, Cvoct/Cv, and 4 parameters related to cerebral tissue accumulation that were measured using a four-head gamma camera 5 and 28 min after 123I-IMP injection. Furthermore, the rCBF values obtained using the input function estimated by this method also closely correlated with the rCBF values measured using the continuous arterial blood sampling (r = 0.912, n = 180).

CONCLUSION

These results suggest that this method would serve as a convenient and less invasive method of rCBF measurement in the clinical setting.

Side-to-side differences in cortical bone mineral density of tibiae in young male athletes

The importance of physical activity in the development and maintenance of bone mineral density (BMD) is widely accepted. However, the effects on cortical BMD have not been clarified in detail. The present study examined bilateral asymmetries in cortical BMD of the tibia using peripheral quantitative computed tomography. Subjects comprised 37 young male athletes and 57 controls (age range, 18-28 years). BMD and geometrical indices were determined in bilateral tibiae. Cortical and trabecular BMD were calculated at the diaphysis and distal metaphysis, respectively. Cortical width, periosteal cross-sectional area, and cross-sectional moment of inertia were calculated using tomographic data of the tibial diaphysis. In athletes, the non-dominant leg showed greater cortical BMD than the dominant leg (mean difference, 5.42%; P < 0.0001). Cortical width and moment of inertia were also greater in the non-dominant leg. Periosteal area displayed no significant difference between legs. The control group exhibited similar results except for cortical BMD. No differences in trabecular BMD were noted between legs in either athletes or controls. These results implies the existence of mechanisms for the mechanical adaptation of cortical BMD. Dominant leg is used for mobility or manipulation whereas the non-dominant leg contributes to support the actions of the dominant leg. Loading differences in bilateral legs in young athletes might affect the remodeling rate leading to the side-to-side differences in cortical BMD.

Fractal analysis of bone architecture at distal radius

Bone strength depends on bone quality (architecture, turnover, damage accumulation, and mineralization) as well as bone mass. In this study, human bone architecture was analyzed using fractal image analysis, and the clinical relevance of this method was evaluated. The subjects were 12 healthy female controls and 16 female patients suspected of having osteoporosis (age range, 22-70 years; mean age, 49.1 years). High-resolution CT images of the distal radius were acquired and analyzed using a peripheral quantitative computed tomography (pQCT) system. On the same day, bone mineral densities of the lumbar spine (L-BMD), proximal femur (F-BMD), and distal radius (R-BMD) were measured by dual-energy X-ray absorptiometry (DXA). We examined the correlation between the fractal dimension and six bone mass indices. Subjects diagnosed with osteopenia or osteoporosis were divided into two groups (with and without vertebral fracture), and we compared measured values between these two groups. The fractal dimension correlated most closely with L-BMD (r=0.744). The coefficient of correlation between the fractal dimension and L-BMD was very similar to the coefficient of correlation between L-BMD and F-BMD (r=0.783) and the coefficient of correlation between L-BMD and R-BMD (r=0.742). The fractal dimension was the only measured value that differed significantly between both the osteopenic and the osteoporotic subjects with and without vertebral fracture. The present results suggest that the fractal dimension of the distal radius can be reliably used as a bone strength index that reflects bone architecture as well as bone mass.

Comparison of vertebral morphometry in the lumbar vertebrae by T1-weighted sagittal MRI and radiograph

PURPOSE

In this study, we investigated the usefulness of T1-weighted sagittal MR images at the lumbar vertebrae in the vertebral morphometry, in comparison with lateral radiographs.

SUBJECTS AND METHODS

The subjects were 42 men (mean age: 53.0 years) and 41 women (mean age: 57.9 years). Both MRI and radiography of the lumbar spine were performed within 1 month. The vertebral body heights and their ratios were measured by the semi-automatic measuring system. The frequency of a vertebral fracture and the absolute value of vertebral body height in both morphometry were compared.

RESULTS

Based on the criteria for prevalent vertebral fracture using vertebral height ratios, the vertebrae were classified into four groups. Group 1 was defined as the vertebrae without fracture (n=347 vertebrae). Groups 2-4 were defined as the vertebrae with fracture; Group 2 by both MRI and X-ray morphometry (n=17), Group 3 by MRI morphometry alone (n=17), and Group 4 by X-ray morphometry alone (n=4). The rate of prevalent vertebral fracture diagnosed by MRI morphometry (8.8%) was higher than that by X-ray morphometry (5.5%). In Group 1, the values of anterior and posterior vertebral height obtained by MRI morphometry were greater than those obtained by X-ray morphometry. On the other hand, the values of central vertebral height obtained by MRI morphometry were smaller than those obtained by X-ray morphometry.

CONCLUSION

Severe biconcave deformity of vertebra can be detected by both MRI and X-ray morphometry, although mild biconcave deformity can be detected only by MRI morphometry.

[Fractal analysis of trabecular architecture: with special reference to slice thickness and pixel size of the image]

Many analyses of bone microarchitecture using three-dimensional images of micro CT (microCT) have been reported recently. However, as extirpated bone is the subject of measurement on microCT, various kinds of information are not available clinically. Our aim is to evaluate usefulness of fractal dimension as an index of bone strength different from bone mineral density in in-vivo, to which microCT could not be applied. In this fundamental study, the relation between pixel size and the slice thickness of images was examined when fractal analysis was applied to clinical images. We examined 40 lumbar spine specimens extirpated from 16 male cadavers (30-88 years; mean age, 60.8 years). Three-dimensional images of the trabeculae of 150 slices were obtained by a microCT system under the following conditions: matrix size, 512 x 512; slice thickness, 23.2 em; and pixel size, 18.6 em. Based on images of 150 slices, images of four different matrix sizes and nine different slice thicknesses were made using public domain software (NIH Image). The threshold value for image binarization, and the relation between pixel size and the slice thickness of an image used for two-dimensional and three-dimensional fractal analyses were studied. In addition, the box counting method was used for fractal analysis. One hundred forty-five in box counting was most suitable as the threshold value for image binarization on the 256 gray levels. The correlation coefficients between two-dimensional fractal dimensions of processed images and three-dimensional fractal dimensions of original images were more than 0.9 for pixel sizes < or =148.8 microm at a slice thickness of 1 mm, and < or =74.4 microm at one of 2 mm. In terms of the relation between the three-dimensional fractal dimension of processed images and three-dimensional fractal dimension of original images, when pixel size was less than 74.4 microm, a correlation coefficient of more than 0.9 was obtained even for the maximal slice thickness (1.74 mm) examined in this study.

Therapeutic effects of alendronate 35 mg once weekly and 5 mg once daily in Japanese patients with osteoporosis: a double-blind, randomized study

The efficacy and safety of treatment with oral alendronate (ALN) 35 mg once weekly for 52 weeks were compared with those of ALN 5 mg once daily in a double-blind, randomized, multicenter study of Japanese patients with involutional osteoporosis. The primary efficacy end point was the percent change from baseline in the lumbar spine (L1-L4) bone mineral density (BMD) after 52 weeks of treatment. In this study, 328 patients were randomized to ALN 5 mg once daily (160 patients) or ALN 35 mg once weekly (168 patients). The adjusted mean percent change from baseline in lumbar spine (L1-L4) BMD after 52 weeks of treatment was 5.8% and 6.4% in the once-daily group and the once-weekly group, respectively (both P < 0.001). The 95% confidence interval for the difference in spine BMD change between the two treatment groups was -0.31% to 1.48%, indicating that the two regimens were therapeutically equivalent, since the confidence interval fell entirely within the predefined equivalence criterion (+/-1.5%). The time course of the spine BMD increase was also similar for both regimens. Regarding total hip BMD, mean changes from baseline at 52 weeks were 2.8% and 3.0% in the once-daily group and the once-weekly group, respectively. In addition, the bone markers (urinary deoxypyridinoline, urinary type-I collagen N-telopeptides, and serum bone-specific alkaline phosphatase) were reduced to a similar level by either treatment throughout the treatment period. The tolerability and safety profiles were also similar between the treatment groups. Taken together, we conclude that the efficacy and safety of the ALN 35-mg once-weekly regimen are therapeutically equivalent to those of the ALN 5-mg once-daily regimen.

Effects of genetic and nutritional factors on bone mineral density in young adults

To estimate the genetic and dietary factors influencing bone mineral density (BMD) in young adults, a total of 53 healthy volunteers (HV) (age 20.89+/-1.34), from whom informed consent was obtained, answered a questionnaire on dietary factors and had DNA from peripheral blood mononuclear cells analyzed for single nucleotide polymorphisms (SNPs) for vitamin (Vit) D receptor (VDR), estrogen receptor alpha (ERalpha), interleukin 1 receptor antagonist (IL1RA), and apolipoprotein E (ApoE) genes. Daily intakes of Vit C, fiber, soybean and related foods, and green and yellow vegetables showed a correlation with % BMD. In addition, Vit B2 as well as Vit C, and vegetables were identified as important factors for BMD by Stepwise regression analysis. Among the SNPs analyzed, the B+ type of the VDR gene tended to be associated with a lower BMD, and pp type of the ER gene digested by the PvuII enzyme in females indicated a significantly lower BMD than that in males. In addition, these SNPs were also identified by factor analysis to be associated with BMD. These results suggested that a complex array of genetic factors, such as two or more SNPs or SNPs and gender, may be important to BMD.

[Diagnosis with bone mass]

In diagnostic criteria of osteoporosis proposed by WHO, the severe osteoporosis is defined as a patient with a value for BMD or BMC more than 2.5SD below the young adult mean value in the presence of one or more fragility fractures. When severe fragility fracture occurs from the second to forth lumbar vertebra, the lumbar BMD could be over-estimated. On the other hand, when the lumbar BMD is markedly low, the demarcation of bone contour is incomplete, and the precision of the BMD measurement decreases. Thus, in the severe osteoporosis it is necessary to be careful in the diagnosis with bone mass using DXA.

Biochemical markers for the detection of bone metastasis in patients with prostate cancer: diagnostic efficacy and the effect of hormonal therapy

In the present study, we investigated the diagnostic effectiveness of biochemical markers of bone turnover for the detection of bone metastasis from prostate cancer and changes in the levels of these markers caused by hormonal therapy. Ninety-five patients with prostate cancer were divided into one of three groups: 26 patients with bone metastasis (BM(+)), 35 patients without bone metastasis on nonhormonal therapy (BM(-)HT(-)) and 34 patients without bone metastasis on hormonal therapy (BM(-)HT(+)). All patients in the BM(+) group had received hormonal therapy. Serum or urinary levels of the following biochemical markers of bone turnover were examined: bone-specific alkaline phosphatase (B-ALP), osteocalcin (OC), type I procoIlagen C-propeptide (PICP), type I collagen cross-linked C-telopeptide (ICTP), C-telopeptide fragment (CTx), N-telopeptide fragment (NTx), total pyridinoline (T-Pyr), total deoxypyridinoline (T-D-Pyr) and free deoxypyridinoline (F-D-Pyr). The BM(+) group showed significantly higher values than the BM(-)HT(-) group for B-ALP, PICP, NTx, CTx, T-Pyr, T-D-Pyr, and F-D-Pyr. Compared with the BM(-)HT(+) group, the BM(-) group showed significantly higher values for B-ALP, ICTP, NTx, T-Pyr and T-D-Pyr. The levels of B-ALP, NTx, CTx, T-D-Pyr and F-D-Pyr were significantly different between the BM(-)HT(-) and BM(-)HT(+) groups. All markers, except OC and CTx, significantly were correlated with the extent of bone metastasis on bone scintigraphy. Of all markers, receiver operating characteristic (ROC) analyses revealed B-ALP and F-D-Pyr to be the most sensitive and specific for differentiation between the BM(+) and BM(-)HT(-) groups with regard to bone formation and resorption. respectively. In contrast, B-ALP and ICTP were most sensitive and specific for differentiation between the BM(+) and BM(-)HT(+) groups. The results suggest that hormonal therapy greatly affects the efficacy of PICP, CTx and F-D-Pyr in the diagnosis of bone metastasis, whereas its effects on ICTP are small. Although bone metabolic markers would be useful in the diagnosis of bone metastasis from prostate cancer, the effects of hormonal therapy on bone metabolism should be kept in mind in their evaluation.

[Usefulness of 67Ga scintigraphy in deciding surgical indication in secondary hyperparathyroidism]

In order to evaluate the usefulness in deciding surgical indication in secondary hyperparathyroidism (SHP), 67Ga scintigraphy was performed in 37 patients of SHP before parathyroidectomy (PTx). The radionuclide accumulation in skull and submandible was classified into 4 patterns (skull-submandibular pattern, skull pattern, submandibular pattern and normal pattern). Serum alkaline phosphatase levels were significantly elevated in patients of skull-submandibular pattern (13 cases) compared with skull pattern (6 cases), submandibular pattern (6 cases) and normal pattern (12 cases). Serum intact parathyroid hormone levels were significantly elevated in patients of skull-submandibular and skull patterns compared with normal pattern. No significant difference was observed among the weight of resected parathyroid glands. In 4 of 6 patients of normal pattern on 67Ga scintigram, bone scintigraphy showed a characteristic pattern of SHP including an increased accumulation in the skull and submandible. Bone mineral density (BMD) in the distal radius was increased within six to twelve months after PTx in 10 of 11 patients of skull-submandibular pattern on 67Ga scintigram, whereas only one patient showed an increase in BMD in 9 patients of normal pattern. In summary, it was concluded that 67Ga scintigraphy could provide a useful information in deciding the indication for PTx in secondary hyperparathyroidism.

[Chronological study for solitary bone metastasis in the sternum from breast cancer with bone scintigraphy]

Since breast cancer is frequently associated with bone metastasis, bone scintigraphies have been performed to determine pre-operative staging and to survey postoperative bone metastasis. The sternum, in particular, is a site at which is difficult to differentiate between benign bone disease and bone metastasis, because of varied uptake and wide individual variations. In this study, chronological bone images were scintigraphied in six cases with solitary sternal metastasis and three cases with benign bone disease including two fracture cases and one arthritis case. On bone scintigrams in which solitary sternal metastasis appeared, increased uptake was found in five cases, and photon deficiency was observed in one case. During follow-up scintigraphies, abnormal accumulations, such as hot spots and cold lesions, increased in the bone metastasis while abnormal uptake disappeared or was unchanged in the benign bone disease cases. On CT, four cases showed osteolytic change, and one exhibited osteosclerotic change. These findings indicate that sternal metastasis usually shows osteolytic change, even if a hot lesion is recognized on bone scintigraphy. In solitary sternal metastasis, for which early diagnosis is difficult, both an integrated diagnosis using other imaging techniques and chronological bone scintigraphy are important.

[Development of a simple method for the washout correction of 123I-IMP SPECT and its application to a quantitative rCBF method]

We have developed a simple method to correct the washout of tracer from the brain based on the two-compartment model in brain early SPECT using N-isopropyl-p-[123I]iodoamphetamine (123I-IMP). This correction was applied to a new quantitative method of regional cerebral blood flow (rCBF) in combination with the microsphere method by continuous arterial sampling previously reported. Data acquisition of 123I-IMP early SPECT was started from 35 min after 123I-IMP i.v. injection, and the time activity curve of whole brain on anterior head planar images was monitored immediately after 123I-IMP i.v. injection for the correction of washout of tracer from the brain. The usefulness of this method was evaluated in 12 patients with various brain diseases by comparison with the results obtained from the super-early SPECT at 7-10 min after 123I-IMP i.v. injection. The washout rates in cases of early SPECT corrected by this method ranged from 16.91% to 39.34% with a mean +/- SD of 27.72 +/- 5.44%. The contrast of hypo- to hyperperfusion regions on early SPECT was improved by the correction of the washout, and its intracerebral distribution was similar to the simultaneously obtained super-early SPECT images. These results indicated that the present correction method for the washout was useful for more correct quantification of rCBF.

Rates of change in spinal bone density among Japanese women

To determine the rates of change in bone mineral density (BMD) at the spine in healthy Japanese women, longitudinal measurements of spinal BMD using dual X-ray absorptiometry were collected from 984 women over 17 years of age (mean age 51.6) at eight medical research centers. They were followed up for 20.9 months on average without any treatment influencing bone and calcium metabolism. Measurements of BMD obtained by two different scanners were converted into standardized BMD (sBMD) values. The multiple linear regression model predicts that spinal sBMD increases up to about 23 years of age: the estimated average rates of increases were 0.13%/year for women aged 20 years. After the age of 23, the sBMD began decreasing: the rates of loss increased by 0.045%/year for each year increase in age among premenopausal women. In perimenopausal women, the rate of loss was 2. 1%/year. In postnatural menopausal women, the rates of loss decreased exponentially with increasing years since menopause. The rates of loss increased by 0.04%/year for 1 kg decrease in body weight or by 0.1%/year for 1 kg/m2 decrease in body mass index. No significant differences in changes in sBMD were found between scanners and between centers after multiple adjustment. We conclude that the rates of change in spinal sBMD are associated with age in premenopausal women, and with years since menopause and weight or BMI in postmenopausal women. Caution is needed, however, when using data from different densitometers to evaluate rates in bone loss in multicenter trials.

Calcaneus as a site for the assessment of bone mass

The calcaneus is a skeletal site frequently used for monitoring bone loss after spaceflight, because it is sensitive to microgravity-induced bone mineral loss and reflects the degree of demineralization in the vertebra and the femoral neck. In this article, methods for assessing the calcaneus are reviewed, and their potential applications and limitations as the monitoring site for bone loss in weightlessness are discussed. Currently, single or dual energy X-ray absorptiometry appears to be most sensitive for monitoring bone mineral loss in weightlessness. The results of recent studies suggest two- to threefold longer follow-up times required for ultrasound techniques. However, ultrasound devices can be designed to be portable, making them attractive for inflight use, and ultrasound techniques are expected to provide information related to bone quality. Additional investigations that assess new ultrasound techniques would be important to determine and utilize the full potential of this technology for monitoring bone loss in weightlessness.

Bone mineral measurement in Japan

Various methods for evaluating bone mineral in appendicular, and axial bone or in the whole skeleton have recently become available. As bone mineral is one of the major determinants of bone strength, its exact measurement should be useful for the diagnosis of osteoporosis, as well as for the prediction of fracture risk and monitoring of therapeutical response. The aims of this paper are to review the fundamental performance of bone mineral measurements, the improvements in DXA systems, and the progress in site-specific bone mineral instruments for the radius and calcaneus used in Japan, and to introduce diagnostic criteria for primary osteoporosis, and report on annual rates of bone loss in Japanese females.

[Comparative study on the tumor accumulation of 99mTc-tetrofosmin and 99mTc-MIBI in rabbits bearing VX-2 cancer]

Each of myocardial blood flow imaging agents has a potential usefulness as an agent for tumor scintigraphy. The tumor accumulation and washout of 99mTc-tetrofosmin and 99mTc-MIBI were comparatively studied using rabbits bearing VX-2 cancer. From seventeen to twenty days after the implantation of VX-2 cancer into the femoral region of seven rabbits, tumor to soft tissue accumulation ratio (T/S ratio) of each agent was calculated in early images (5 min after injection) and in late images (50 min after injection). Compared with 99mTc-tetrofosmin, the T/S ratio of 99mTc-MIBI was higher and, moreover, the washout was delayed. These results suggest that there is a difference in tumor accumulation property between these two agents.

[Compartment analysis of 123I-iomazenil brain on early and delayed SPECT]

We investigated the characteristics of 123I-Iomazenil (IMZ) SPECT images in 12 adults (six males and six females, with a mean age of 56.1 years). The washout rate of 123I-IMZ from the brain was estimated from two SPECTs done 15 min and 3 hr after injection. Although the washout was relatively slow, the rates differed in each intracerebral region, suggesting that the distribution of 123I-IMZ was gradually changing. Furthermore, assuming 123I-IMZ kinetics in the brain for the three-compartment, two-parameter model, the transition rate constant (K1) from the blood to the brain and the binding potentials (BP) of benzodiazepine to the receptor were calculated. The BP and K1 values were compared with 123I-IMZ SPECT counts and CBF values by 123I-IMP. The BP values correlated more closely with the counts on the delayed SPECT than those on the early SPECT. It was confirmed that delayed SPECT images reflect better the distribution of the benzodiazepine receptor than early images do. On the other hand, the K1 values correlated highly with CBF obtained by 123I-IMP, and this finding suggested that super-early SPECT images might be remarkably influenced by the distribution of CBF.

Age-related changes in vertebral height ratios and vertebral fracture

Because no gold standard for the definition of vertebral fracture exists, there has been controversy about whether mild vertebral deformities are truly fractures or simply normal variation in vertebral size and shape. The aim of this study was to assess the associations of mild variations of vertebral height ratios to definite vertebral fractures. In 479 Japanese women (aged 53.9 +/- 9.1 years) who visited our institute for a medical checkup, we performed lateral lumbar radiographs and morphometric parameters were derived by measuring the anterior (Ha), middle (Hm) and posterior (Hp) height of each vertebral body from T12 to L4. Vertebral height ratios, Ha/Hp, Hm/Hp or Hp/Hp' of adjacent vertebrae that were more than 3 SD different from vertebra-specific means of normative data were considered to indicate fractures. Forty-five women were diagnosed with at least one fracture. After excluding the subjects with vertebral fracture, we examined the associations of the variations in vertebral height ratios with age, anthropometric parameters and lumbar bone mineral density (BMD) measured by dual-energy X-ray absorptiometry. Vertebral height ratios, especially Hm/Hp in postmenopausal women, tended to decrease with age and were positively associated with BMD. No significant correlation was observed between anthropometric parameters and vertebral height ratios. Aged-related decrease in vertebral height ratios (Ha/Hp and Hm/Hp, each averaged from T12 to L4) was significant even after the correction for BMD. Mean values of height ratios of non-fractured vertebrae adjusted for age and BMD were significantly lower in postmenopausal women with vertebral fracture than in those without vertebral fracture. Logistic regression analysis showed that BMD and height ratios of non-fractured vertebrae were independent predictors of vertebral fracture risk. The results suggest that older women, and women with at least one obvious (3 SD) fracture, tend to have mild deformities which do not qualify using the 3 SD definition. These mild deformities may represent real consequences of osteoporosis, because they are more pronounced among women with obvious fracture.

Sex and age patterns of quantitative ultrasound densitometry of the calcaneus in normal Japanese subjects

: The speed of sound (SOS), broadband ultrasound attenuation (BUA), and the stiffness index (stiffness), which was derived from SOS and BUA, were measured on the calcaneus using the Achilles ultrasound densitometer (Lunar) in normal Japanese woman (n = 473) and men (n = 218). Sex differences and age-related changes in these variables were investigated. In addition, the bone mineral density (BMD) of the lumbar vertebrae measured by dual X-ray absorptiometry (QDR-2000, Hologic) was compared with SOS, BUA, and stiffness. There were some decreases of ultrasound variables in both young adult men and women. BMD values were similar in young adults of both sexes. BMD was relatively stable in women from 20 to 49 years, then decreased at about 1.5%/year. Ultrasound variables were higher in males than females at all ages, and they decreased from age 20 onward in both sexes with an annual loss of about 0.6%. Age-related changes in SOS, BUA, and stiffness were different from those in BMD in normal Japanese subjects. The correlations between BMD and SOS and BUA and stiffness were higher in women (r = 0.51-0.64) than in men (r = 0. 43-0.49).

Influence of exercise and degenerative vertebral changes on BMD: a cross-sectional study in Japanese men

The effects of recreational exercise and milk intake on BMD were assessed in Japanese men using analysis of covariance with significant predictor variables, selected from age, height, body weight and body mass index (BMI), as covariates. The influence of degenerative vertebral changes on these effects was also evaluated. Recreational exercise was found to be positively associated with BMD at the lumbar spine and the femoral neck, whereas milk intake, a possible indicator of calcium intake in the Japanese, was positively associated with BMD at the radius and the lumbar spine. Not only vertebral BMD but also radial and femoral neck BMD was higher in the subjects with osteophytosis or sclerosis in the lumbar vertebrae. Neither exercise nor lumbar pain was significantly related to these vertebral changes. These data suggest a protective effect of regular recreational exercise and milk intake on bone health in Japanese men.

[Study on tumor accumulation property of 99mTc-HM-PAO and 99mTc-MIBI in rabbits bearing VX-2 cancer]

Each of blood flow imaging agents has a potential usefulness as an agent for tumor scintigraphy. The usefulness for tumor scintigraphy of two agents, i.e. cerebral blood flow scintigraphy agent 99mTc-HM-PAO and myocardial blood flow scintigraphy agent 99mTc-MIBI, was comparatively studied using rabbits bearing VX-2 cancer. From then to twenty days after the implantation of VX-2 cancer into the femoral region of five rabbits, tumor to soft tissue accumulation ratio (T/S ratio) of each agent was calculated in early images (5 min after injection) and in late images (50 min after injection). Compared with 99mTc-MIBI, the T/S ratio of 99mTc-HM-PAO was higher and, moreover, the washout was delayed. These results suggest that there is a difference in tumor accumulation property between these two agents.

A fundamental study of a computed X-ray densitometry system for bone mineral measurement in the second metacarpal bone

The effect of radiographic exposure factors such as the photographic film density, X-ray tube voltage, and focus-film distance on the indices of bone mineral obtained by computed X-ray densitometry (CXD), a newly developed X-ray microdensitometric system, was investigated. sigma GS/D, which corresponded to the bone mineral density divided the integrated bone mineral by the bone width of the second metacarpal bone, was influenced by these exposure factors, whereas MCI, which represented the ratio of the cortical bone to whole bone, was independent of them. Present results indicated that the focus-film distance between 85 and 115 cm, the X-ray tube voltage in 45-60 kV, and a photographic density of lower than 1.82-1.86 of the screen-film combination should be used to assess quantitatively bone mineral of the second metacarpal bone using the CXD system.

[Usefulness of 99mTc-ECD SPECT in diseases of the central nerve system: special reference to a comparison with 123I-IMP and 99mTc-HM-PAO SPECT]

The usefulness of a new cerebral perfusion imaging radiopharmaceutical, 99mTc-ethyl cysteinate dimer (ECD), was clinically evaluated. The subjects of this study were 14 patients with neurological disorders including 10 patients with cerebral infarction and 4 patients with other diseases. A total of 15 examinations was performed. 99mTc-HM-PAO or 123I-IMP SPECTs were performed simultaneously, and the findings from those examinations were compared with 99mTc-ECD. As to the count ratio of lesions to normal area (L/N), the L/N ratio in severe ischemic patients was lower in 99mTc-ECD than in 99mTc-HM-PAO or 123I-IMP. In mild ischemic patients, on the other hand, the L/N ratio was the lowest in 123I-IMP. When the relationship between rCBFs obtained from 123I-IMP and the values of L/N in 99mTc-ECD or 99mTc-HM-PAO was compared, the values of L/N in 99mTc-ECD or 99mTc-HM-PAO were found to have decreased linearity with increasing rCBF. In a patient showing luxury perfusion, the accumulation pattern of 99mTc-ECD was different from that of the other two radiopharmaceuticals, and focal defect was revealed in 99mTc-ECD SPECT. On the dynamic SPECT of 99mTc-ECD in a patient with meningioma, the tumor showed a change from high to low perfusion with the passage of time. This finding indicated that care should be taken in the evaluation of accumulation of 99mTc-ECD. Therefore, 99mTc-ECD was found to be useful as a cerebral perfusion agent. In addition, as accumulation of 99mTc-ECD might somehow reflect metabolism in some cases, further careful investigation of many cases should be carried out.

Confirmation of dialysate leakage by intraperitoneal administration of radioactive colloid

A 29-year-old man who had been on continuous ambulatory peritoneal dialysis (CAPD) was admitted to our hospital because of pleural effusion. Radioactive colloid studies with intraperitoneal administration revealed a pleuroperitoneal communication. After pleurodesis by the administration of fibrin glue and antiplasmin into the thoracic cavity, the pleural effusion did not reaccumulate and there was no evidence of pleuroperitoneal communication by radioactive colloid study.

Accumulation of 99mTc-HM-PAO in photon deficient areas in bone scan of bone metastasis from hepatocellular carcinoma

To evaluate bone metastasis from hepatocellular carcinoma (HCC), both bone and 99mTc-HM-PAO scintigraphies were performed in six patients with clinically and pathologically confirmed HCC. Two patients had a bone scintigram which revealed abnormal accumulation in the skull base, pelvic bone and thoracic spine. The 99mTc-HM-PAO scans of both these patients also showed abnormal accumulation in the same sites. The bone scintigrams in one patient revealed not only abnormal accumulation in the ribs but also photon deficient areas in the sternum, thoracic spine and femur, while 99mTc-HM-PAO scans showed abnormal accumulation in all these sites. In three patients, bone scintigraphy revealed photon deficient areas in the ribs, pelvic bone and femur, and their 99mTc-HM-PAO scintigrams showed abnormal accumulation in the same sites. Thus, it was shown that, in the detection of bone metastasis from HCC by means of bone scintigraphy, it was necessary to pay attention to hot and cold lesions, and that a combination study with 99mTc-phosphorous compounds and 99mTc-HM-PAO was useful in evaluating these lesions.

[A fundamental study of 99mTc-ethyl cysteinate dimer (99mTc-ECD)]

In vitro fundamental studies of 99mTc-ethyl cysteinate dimer (99mTc-ECD), a newly developed radiopharmaceutical for cerebral perfusion scintigraphy, were performed, and were compared with those of 99mTc-HM-PAO, which has been widely applied to clinical use. 99mTc-HM-PAO should not only be injected soon after reconstitution, but also be avoided mixture with saline or drugs such as Diamox, because of its radiochemical purity decreases with the passage of time and the addition of saline and Diamox. On the other hand, the radiochemical purity of 99mTc-ECD reached a constant level of 94-96% at 30 to 180 min after reconstitution, and it remained stable against the addition of saline and Diamox. Therefore, it was suggested that 99mTc-ECD could be injected from an already saline-infused venous-line or mixed with Diamox. However, early injection after reconstitution should be avoided, because 99mTc-ECD did not become stable enough to maintain sufficient radiochemical purity until 30 min after reconstitution. The present studies are suggested that the red blood cell component is largely related to the metabolism of 99mTc-ECD in blood. Furthermore, from study of the metabolic rate using rabbit blood, it was suggested that a species difference existed in esterase activity in blood.

[Bone mineral determination using dual energy X-ray absorptiometry (DEXA)]

To quantify the appendicular and axial bone mineral with good accuracy and precision, dual energy X-ray absorptiometry (DEXA), DCS-600 (Aloka) for the radius, mainly composed of cortical bone, and QDR-1000 (Hologic) for the lumbar vertebrae, mainly composed of trabecular bone, was used. Bone loss with aging was earlier in females than that in males, and it was also more prominent in the lumbar vertebrae than that in the radius. Furthermore, the vertebral fracture rate could be evaluated by calculating percentile of an individual bone mineral density to the peak bone mass. Thus, the bone mineral determination using DEXA in both the appendicular and axial bone will provide a useful information in the assessment of bone loss, and the detection of the patients with high risk of fracture in osteoporosis.

New perspectives for diagnosis of nodular goiter by technetium-thallium subtraction scanning

To improve the scintigraphic differential diagnosis of thyroid nodules, Tc-99m pertechnetate-Tl-201 Cl subtraction scintigraphy (Tc-Tl subtraction scanning) was performed in 106 patients with various histologically proven thyroid nodules. Results were evaluated by comparison with surgical findings and preoperative ultrasonographic results. Thyroid nodules were more successfully detected by Tc-Tl subtraction scanning than by either Tc-99m pertechnetate or Tl-201 Cl scintigraphy alone. Detection of nodules was further improved when images recorded by the three methods were integrally observed (sensitivity 83%, accuracy 89%), with detectability approaching that of ultrasonography. False-positive or -negative Tc-Tl subtraction scans were obtained principally when multiple nodules were present (7 cases) or when no discrepancy existed between the accumulations of Tc-99m pertechnetate and Tl-201 Cl (18 cases). Most colloid nodules exhibited irregular margins, heterogeneous internal accumulations of Tl-201 Cl, and distorted shapes on Tc-Tl subtraction scans, while the majority of adenoma were oval-shaped with smooth margins. Carcinoma were characterized by homogeneous internal accumulation of Tl-201 Cl and distorted shapes.