Migita Hisashi, Rikimaru Hideaki, Rikimaru-Nishi Yukiko, Koga Noriyuki, Watanabe Koichi, Ohta Keisuke, Nakamura Kei-Ichiro, Kiyokawa Kensuke
From the Department of Plastic and Reconstructive Surgery and Maxillofacial Surgery.
Division of Microscopic and Developmental Anatomy, Department of Anatomy.
Ann Plast Surg. 2020 Apr;84(4):379-384. doi: 10.1097/SAP.0000000000002231.
Histological differentiation between hypertrophic scars (HSs) and keloids has been considered difficult. In this study, we analyzed differences in the 3-dimensional tissue architecture between HSs and keloids using focused ion beam/scanning electron microscopy (FIB/SEM).
Five specimens each of normal skin, normotrophic scars (NSs), HSs, and keloids were investigated. Three sites in each specimen were observed by FIB/SEM tomography, resulting in an observation of 15 sites per tissue type. We identified fibroblasts and macrophages and assessed the contact ratio and the mode of intercellular contact (planar contact or point contact). The significance of differences among the 4 tissue types was determined by Fisher exact test.
In normal skin, contact between fibroblasts and macrophages was observed at all 15 sites, and the mode of contact was always planar. There was contact at 87% of the NS sites (planar: point = 80%: 7%). In HSs, contact was seen at 80% of the sites (planar: point = 20%: 60%). In keloids, contact was found at only 15% of the sites (planar: point = 7.5%: 7.5%). The intercellular contact ratio showed no significant differences among normal skin, NSs, and HSs; however, a significant difference was noted between these tissues and keloids. The intercellular contact mode also showed no significant difference between normal skin and NSs, but a significant difference between these tissues and HSs.
These histopathologic findings suggest that FIB/SEM tomography is useful for distinguishing between HSs and keloids and can provide important knowledge for understanding the pathogenesis of keloids.
肥厚性瘢痕（HSs）和瘢痕疙瘩之间的组织学鉴别一直被认为具有挑战性。在本研究中，我们使用聚焦离子束/扫描电子显微镜（FIB/SEM）分析了HSs和瘢痕疙瘩之间三维组织结构的差异。
对正常皮肤、正常瘢痕（NSs）、HSs和瘢痕疙瘩各5个标本进行研究。通过FIB/SEM断层扫描观察每个标本中的3个部位，每种组织类型共观察15个部位。我们识别成纤维细胞和巨噬细胞，并评估接触比例和细胞间接触模式（平面接触或点接触）。通过Fisher精确检验确定4种组织类型之间差异的显著性。
在正常皮肤的所有15个部位均观察到成纤维细胞与巨噬细胞之间的接触，且接触模式均为平面接触。在NSs的87%的部位观察到接触（平面接触：点接触 = 80%：7%）。在HSs中，80%的部位观察到接触（平面接触：点接触 = 20%：60%）。在瘢痕疙瘩中，仅15%的部位观察到接触（平面接触：点接触 = 7.5%：7.5%）。细胞间接触比例在正常皮肤、NSs和HSs之间无显著差异；然而，这些组织与瘢痕疙瘩之间存在显著差异。细胞间接触模式在正常皮肤和NSs之间也无显著差异，但这些组织与HSs之间存在显著差异。
这些组织病理学发现表明，FIB/SEM断层扫描有助于区分HSs和瘢痕疙瘩，并可为理解瘢痕疙瘩的发病机制提供重要知识。
