老化對人類眼輪匝肌組織型態特徵之影響

Abstract

眼輪匝肌 (Orbicularis oculi muscle) 在眼睛四周的解剖構造中佔了關鍵地 位，並在這區域的老化過程中扮演了重要角色。眼睛四周的年輕化 (Peri-orbital rejuvenation) 一直是整形外科領域中極有興趣的課題，我們相信藉由了解眼輪匝 肌老化相關的變化，將對改善現有的年輕化技術或開發新的年輕化方法建立深入 研究的基礎。然而文獻中並沒有任何相關的研究報告，因為眼輪匝肌的採樣不僅 困難且有傷及眼球的危險。 事實上在眼皮整型手術中所切除的軟組織中即含有小部分的眼輪匝肌，所以 我們以在國立台灣大學醫學院附設醫院接受上眼皮整型手術 (Upper blepharoplasty) 的病人為對象，取得不同年紀病人的眼輪匝肌樣本。 此研究的目的是以組織型態學的方法評估人類眼輪匝肌因老化產生的各型 肌肉纖維組成變化。眼輪匝肌的肌肉樣本自手術中取得後立刻在液態氮中做冷凍 包埋，接著送病理科切片，對肌纖維中的腺三磷酸酵素 (ATPase) 作特殊染色。 我們在顯微鏡下觀察這些切片並選擇具橫斷切面的適當區域照相，相片掃描入電 腦後以影像處理軟體分析即可得到該區域中各肌肉纖維的數目及其所佔的面 積，並可進一步算出不同肌肉纖維間的比例及其平均直徑。 將接受上眼皮整型手術的病人依年齡分組，每組中計算所得的各型肌肉纖維 的數目，其所佔的面積，即可相互比較，進而推估人類眼輪匝肌因老化產生的相 關變化。

Orbicularis oculi muscle is a key structure in the peri-orbital anatomy and is responsible for the major changes of aging in this area. Peri-orbital rejuvenation has been an issue of great interest in plastic surgery. We believe that understanding the age-related changes in orbicularis oculi muscle is important for improving the current rejuvenation techniques or developing the new ones. Nevertheless, a study focusing on this topic has never been performed before, simply because it is difficult and dangerous to perform needle biopsy on orbicularis oculi muscle. We recruited patients who received upper blepharoplasty in National Taiwan University Hospital as our subjects. Taking advantage of the discarded soft tissue in the blepharoplasty surgery, samples of orbicularis oculi muscle can be easily obtained from patients of various ages. In our study, the muscle specimens are mounted for transverse section and frozen in liquid propane chilled with liquid nitrogen. Muscle fiber types can be classified 2 with myofibrillar ATPase staining. The ATPase-stained muscle sections were processed as a videoprint. Suitable areas of each section containing transversely cut muscle fibers were photographed. The image file was processed with an image analysis system. The number of each fiber per photographed area and the cross sectional area of each fiber can be determined. By dividing the subjects who had their orbicularis oculi muscle sampled during upper blepharoplasty operation into age groups, the different muscle type compositions can be compared among the different groups. Therefore, the age-related changes in fiber type compositions fiber cross section areas of human orbicularis oculi muscle can be concluded.