Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1433-2965
    Keywords: Key words:Histomorphometry – Osteoporosis – Pamidronate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract: The effect of pamidronate therapy on bone histology was studied in patients with osteoporosis with at least one vertebral fracture in a randomized, double-masked, placebo-controlled, multi-center trial. Patients received pamidronate 150 mg/day or placebo in addition to calcium 500 mg/day and vitamin D3 400 IU/day. Transiliac bone biopsies were obtained before and after 1 or 2 years of treatment. Of these, 23 pairs of biopsies obtained from 14 women and 9 men (mean age þ SD, 61.5 þ 10 years) were of sufficient quality for histomorphometry. Histomorphometry was performed on sections stained with Goldner’s trichrome, using a drawing tube and a digitizer. Urinary hydroxyproline excretion decreased significantly (p〈0.005) following pamidronate treatment, indicating a decrease in bone resorption. Osteoid volume and osteoid surface also decreased significantly in the pamidronate group (p〈0.004 and p〈0.003 respectively), consistent with a secondary decrease in bone formation. Osteoid variables did not change in the placebo-treated patients. Cortical thickness, trabecular bone volume and trabecular thickness did not change after pamidronate or placebo treatment. Wall thickness, however, showed a borderline increase following pamidronate treatment. After pamidronate, eroded surface and mineral apposition rate did not change significantly in the placebo and pamidronate groups. Mineralizing surface and activation frequency showed a borderline decrease in the placebo and pamidronate groups. The decrease in mineralization lag time was of borderline significance in the pamidronate group, corroborating the absence of any negative effect on mineralization. In conclusion, pamidronate treatment led to a decrease in bone turnover and did not interfere with bone mineralization.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1619-7089
    Keywords: Bones ; Mineral ; Dual photon absorptiometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To determine the short-term reproducibility of bone mass calculations with dual photon absorptiometry of the lumbar spine (L2–L4), duplicate measurements in healthy subjects were used. Three different methods for selection of region of interest were compared: a rectangular region with variable height and width, an irregular region to be drawn freely by the operator and the standard calculation software supplied with the bone densitometer. Contributions of changes in size and location of the region of interest on calculated bone mineral mass were also investigated. An increase in height of the region by 2 scan lines caused an increase in bone mineral content (BMC) of 8.4%±1.8%. Enlargement in width by 2 pixels in each scan line caused an increase in BMC of 2.5%±1.3%. The difference between these region of interest changes was significant (P0.0005). The use of a rectangular region, optimized to enclose L2–L4 in each person but of the same size in both measurements, resulted in a reproducibility of 1.4% and 0.7% respectively for 2 observers, with an inter observer variation of 1.2%. The reproducibility of the duplicate measurements was worse for the other methods of region of interest selection. A further series of duplicate DPA measurements in normal subjects, but with a standard meal between the measurements, showed a larger variation in the results. Again the reproducibility of the calculations using the rectangular region was better than with the other methods, with much less inter observer variation. These data suggest that calculation of dual photon absorptiometry results with a constant region of interest is preferred for the detection of small changes in lumbar bone mass.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    European journal of nuclear medicine 15 (1989), S. 269-273 
    ISSN: 1619-7089
    Keywords: Bones ; Mineral ; Single photon absorptionmetry ; Dual photon absorptiometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The reproducibility of single photon absorptiometry (SPA) results for detection of changes in bone mineral content (BMC) was evaluated in a clinical setting. During a period of 18 months with 4 different sources, the calibration scans of an aluminium standard had a variation of less than 1% unless the activity of the 125I source was low. The calibration procedure was performed weekly and this was sufficient to correct for drift of the system. The short term reproducibility in patients was assessed with 119 duplicate measurements made in direct succession. The best reproducibility (CV=1.35%) was found for fat corrected BMC results expressed in g/cm, obtained at the site proximal to the 8 mm space between the radius and ulna. Analysis of all SPA scans made during 1 year (487 scans) showed a failure of the automatic procedure to detect the space of 8 mm between the forearm bones in 19 scans (3.9%). A space adjacent to the ulnar styloid was taken as the site for the first scan in these examinations. This problem may be recognized and corrected relatively easy. A significant correlation was found between BMC of the lower arm and BMC of the lumbar spine assessed with dual photon absorptiometry. However, the error of estimation of proximal BMC (SEE=20.0%) and distal BMC (SEE=19.4%) made these measurements of little value to predict BMC at the lumbar spine in individuals. The short term reproducibility in patients combined with the long term stability of the equipment in our clinical setting showed that SPA is a reliable technique to assess changes in bone mass at the lower arm of 4% between 2 measurements with a confidence level of 95%.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...