在全球,失智症的人口數越來越多,而在臨床上的診斷率卻只有大約 25%,傳統的 診斷方式依靠臨床的評量以及問診,影像學的檢查主要是為了排除其他內科方面的疾 病,近期的診斷方式加入了 Biomarkers 來輔助診斷,期望能提高臨床失智症的診斷率到 50%。其中類澱粉蛋白正子造影對於失智症的病程預測有很大的幫助,而早期判讀類澱粉 蛋白正子造影影像的方法主要是依靠視覺評估的方式來做判讀,結果的準確性依靠的是 臨床醫師的經驗,後來有了量化分析的方法標準攝取值比值法的出現,對於類澱粉蛋白 正子造影的結果有了比較客觀的依據。但此方法也有些缺點,會受到年齡因素的影響, 因此此方法陽性的結果大約只有 50%的患者真的是有罹患阿茲海默氏症。 本文提供另外的量化分析方法叫做閾值區域比值法,此方法較不會受到其他的因素 而影響判讀的結果。本文比較了不同的造影藥劑、不同的性別、年齡以及不同群組之間 的分析結果,以視覺評估當作黃金標準,來和標準攝取值比值法做比較。最後再以臨床 檢查的病例來做驗證,得到的結果有很高的準確率,尤其是 TRR_80 的結果特異性明顯比 標準攝取值比值法來的好,代表著此方法分析結果為陽性的話,病患腦中有不正常的類 澱粉蛋白沉積的情形可信度是很高的。而 TRR_OTSU 的方法較適合用在相同的造影藥劑 的影像上來做分析,這樣的結果對於臨床上會更加的容易使用。 閾值區域比值法分析類澱粉蛋白正子造影影像可以用來早期的偵測患者腦中是否有 不正常的類澱粉蛋白堆積,能夠提早治療延緩病程的發展,能夠有效提高臨床失智症的 診斷率,而且操作上也很快速簡便,對於改善臨床報告品質有很大的幫助。
The number of people with dementia is increasing in the world, but the clinical diagnosis rate is only about 25%. Traditional diagnostic methods depend on the clinical evaluation and consultation. For medical diseases, recent diagnostic methods have added biomarkers to assist in the diagnosis, and it is hoped that the diagnosis rate of clinical dementia can be increased to 50%. The method of Amyloid PET is mainly to make interpretations of visual assessment. The accuracy of the results is based on the experience of clinicians. Later, the quantitative analysis method called the standard uptake value ratio (SUVr) appears. For Amyloid PET result has a more objective basis. However, this method has some shortcomings, because the elders have Amyloid deposits in the brain. Therefore, only about 50% of patients with positive results of this method are really suffering from AD. This article provides another quantitative analysis method called the threshold based region ratio (TRR), which is less affected by other factors that affect the interpretation result. Here we compare the analysis results between different tracers, genders, ages, and groups, and then verify the results with clinical examination cases. The results obtained have a very high accuracy rate. The specificity of TRR_80 is sbetter than that of SUVr, which means that if the analysis result of this method is positive, there is a high degree of certainty that the patient has abnormal amyloid deposits in the brain. The TRR_OTSU method is more suitable for analysis on the image of the same tracer. This result will be easier to use in clinical practice. TRR method to analyze Amyloid PET images can be used to find out whether there is abnormal amyloid accumulation in the brain at the early stage. It can improve the diagnosis rate of dementia, and it’s helpful for improving the quality of clinical reports.