Fourier and fractal analysis of maxillary alveolar ridge repair using platelet rich plasma (PRP) and inorganic bovine bone.

This report concerns the regeneration of the maxillary alveolar process in a 17-year-old patient who had lost the upper central incisors together with alveolar bone as a result of a car accident. Three months later, GBR (guided bone regeneration) was started with the use of autogenic platelet rich plasma (PRP) and inorganic bovine bone. The regenerated bone was analysed after 10 months and compared with intact bone using Fourier analysis of radiograms. The radial and spatial distribution of Fourier transforms showed that the original trabecular pattern existing in the intact bone on both sides of the defect was replicated in an evident way in the regenerated bone. Fractal analysis of intact and regenerated bone showed a higher fractal dimension for intact bone in comparison with regenerated bone, confirming a lower complexity of the newly formed trabecular structures. Replication of the original trabecular pattern in regenerated bone allows us to conclude that genetic mechanisms are influencing the organization of the trabecular pattern of regenerated bone tissue, probably under the influence of the growth factors contained in autologous PRP.

The trabecular structure of developing human mandible.

In this paper we tried to analyse in quantitative terms the differences in trabecular structure of human mandibles 8, 10 and 12 weeks old. The analysis was performed on decalcified Sirius-red stained trabeculae, photographed in polarised light. The data obtained from Fourier transforms of scanned pictures were evaluated by discriminant analysis to show the differences between the analysed stages of development. Also, various parts of the mandible were compared because the clinical experience shows that the frequency of pathological changes is different in different parts of mandible bone. The complexity of trabecular structure of bone samples was measured by fractal dimension. It is concluded that this quantitative approach is reliable and, in the future, could be used for physiological and pathological analyses of bone biopsies.

Diagnostic accuracy of mammography and scintimammography in detection of primary breast cancer related size of the tumour.

BACKGROUND: The detection of breast cancer relies on physical examination and mammography (XMM). The sensitivity of conventional imaging is lesions-size dependent. However, mammography has good sensitivity in small tumours when microcalcification is present, but the sensitivity is relatively low in other small tumours. The use of scintimammography with Tc-99m sestaMIBI (SMM) may be helpful in this situation. The aim of this study is to compare the diagnostic accuracy of mammography and scintimammography across all groups with different sizes of lesions. METHODS: Data for 273 patients aged 26 to 84 years (mean 52; SD 12) with 298 lesions were analysed. All lesions were removed and final histology and pathological size of the tumours were retrospectively reviewed (mean size 2.9 cm, SD 2.4 cm). All patients had XMM and SMM. Each imaging study was graded using five grades of certainty. SMM images were reviewed by an independent specialist blinded to clinical presentation and XMM results. The diagnostic accuracy of each test, overall and by each lesions size subgroup, was compared using receiver operating characteristic curve (ROC) analysis. RESULTS: The sensitivity of scintimammography was consistently high across all size groups; overall 89% (82?100%) compared with 68% (51?88%) for mammography. In those tumours below 2 cm, the area under the ROC was significantly larger with SMM than XMM (p < 0.05), with 80% certainty indicative of greater diagnostic accuracy. Also in all patients the area under the ROC was significantly larger with SMM than XMM (p < 0.05), with 90% certainty indicative of greater diagnostic accuracy. In other groups of lesions size the area under ROC for SMM was larger in lesions size between 2 and 4 cm and slightly smaller in lesions over 4 cm, but it was not significant. CONCLUSION: Scintimammography using Tc-99m sestaMIBI seems to be a sensitive and consistently reliable diagnostic test for breast cancer independent of the size of the tumour.