크레스티드 게코의 골다공증 진단을 위한 골밀도 진단기법평가 = Evaluation of Diagnostic Methodsof Bone Density for Osteoporosisin Crested Gecko

다국어 초록 (Multilingual Abstract)

Nutritional secondary hyperparathyroidism (NSHP) is a common metabolic bone disease (MBD) in captive reptiles, however objective quantitative diagnostic criteria remain unestablished, consequently rendering early diagnosis realistically difficult. This study evaluated the feasibility of quantitative osteoporosis diagnosis in crested geckos (Correlophus ciliatus) using quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA), and investigated whether standard radiography could serve as a quantitative alternative given the limited accessibility of these advanced modalities. We retrospectively analyzed 65 subjects (40 clinically healthy, 22 NSHP, 3 recovered). Imaging was performed without anesthesia, and bone mineral density (BMD) was evaluated at the jaws, long bones, and both anterior and posterior presacral vertebrae (PSV).
QCT demonstrated superior precision (CV: 2.5–4.3%) compared to DXA (CV: 5.6–21.0%). Strong inter-site correlations across anatomical sites (correlation coefficients = 0.70-0.97, all p < 0.05) imply that the disease manifests systemically. Moreover, quantitative evaluation reclassified certain clinically healthy subjects as 'sub-clinical' cases based on their NSHP-level BMD deficits. QCT analysis confirmed a hierarchical sensitivity to bone loss extending from the jaws to the long bones and vertebrae, identifying the posterior vertebrae as the most sensitive indicator. Conversely, DXA failed to show a clear hierarchical pattern due to lower precision. Additionally, body weight exhibited a consistent positive correlation with BMD across all modalities, whereas sex exerted negligible effect. For conventional radiographic analysis, the model based on the average of bilateral humeral measurements yielded the highest correlation with QCT (R² = 0.902) among the various models assessed, accompanied by an acceptable precision for screening purposes (CV: 13.2%).
In conclusion, quantitative assessment using QCT and DXA was confirmed to be a valid method for diagnosing osteoporosis earlier than conventional subjective evaluations. Furthermore, the derived conventional radiographic model proved to be a useful screening tool capable of substituting for these precision instruments in clinical settings.

목차 (Table of Contents)

• Introduction 1
• materials and Methods 4
• Results 19
• Discussion 50
• References 58