活体共聚焦显微镜诊断角膜后部真菌感染与病理诊断的比较研究

A comparative study between in vivo confocal microscopy and pathological examination in diagnosing retrocorneal fungal infection

目的:比较活体共聚焦显微镜和病理检查在角膜后部真菌感染的诊断阳性率,探讨两种检查方法在角膜后部真菌感染诊断中的价值。方法:回顾性病例对照研究。收集2009年11月至2020年12月在青岛眼科医院就诊并进行穿透性角膜移植手术治疗角膜后部真菌感染患者,术前均进行角膜刮片KOH涂片检查和活体共聚焦显微镜检查,术后病变角膜进行病理组织切片、过碘酸-Schiff法(PAS)染色和六亚甲基四胺银法(GMS)染色检查,比较不同检查方法诊断的阳性率。结果:18例角膜后部真菌感染患者角膜刮片KOH涂片均未检查到真菌菌丝,其中有16例患者经活体共聚焦显微镜检查到真菌菌丝(88.9%),而2例患者在术前活体共聚焦显微镜检查中未查到病原体。术后病理检查PAS染色联合GMS染色,18例患者中18例均可检查到真菌菌丝,角膜后部真菌感染患者病理切片中可见角膜深基质层变性坏死,大量炎症细胞浸润,PAS染色和GMS染色可见典型真菌菌丝侵犯角膜基质深层,而角膜基质浅层及上皮层均未查见真菌菌丝。结论:活体共聚焦显微镜诊断角膜后部真菌感染具有一定的局限性,联合术后病理组织切片和特殊染色检查有助于提高角膜后部真菌感染的诊断率。

Objective:To compare the diagnostic rate between in vivo confocal microscopy and pathological examination in retrocorneal fungal infection.Methods:It is a retrospective study.A total of 18 patients with retrocorneal fungal infection and received PKP surgery in the Qingdao Eye Hospital from November 2009 to December 2020 were enrolled.KOH smear and in vivo confocal microscopy examination were performed before surgery,and pathological examination including periodic acid-schiff(PAS)stain and Grocott Methenamine Silver(GMS)stain were performed after surgery.Patients were diagnosed retrocorneal fungal infection based on in vivo confocal microscopy and pathological examination.The diagnostic rates of the two methods were compared.Results:None of the 18 patients with posterior corneal fungal infection were found to have fungal hyphae in the corneal smear.Sixteen patients(88.9%)were found fungal hyphae by in vivo confocal microscopy.Corneal stroma necrosis and a large number of inflammatory cells were shown by postoperative pathologic examination,and all patients were found fungal hyphae in posterior corneal stroma with PAS stain and GMS stain.Conclusion:Confocal microscopy has unique advantages such as non-invasive and rapid examination in the diagnosis of fungal keratitis.However,it needs to combine with pathological examination for diagnosing the retrocorneal fungal infection.