Cordeiro M F, Constable P H, Alexander R A, Bhattacharya S S, Khaw P T
Wound Healing Group, Institute of Opthalmology, London, England.
Invest Ophthalmol Vis Sci. 1997 Jul;38(8):1639-46.
To investigate the effect of varying the treatment area of subconjunctival mitomycin-C (MMC) using an adapted rabbit model of filtration surgery.
Twenty-four New Zealand White rabbits underwent filtration surgery, with random allocation to one of three treatments: 5-minute subconjunctival applications of MMC (0.4 mg/ml) with either a large (8 x 10 mm) or small (4 x 2 mm) sponge or no treatment (control). Drainage was achieved by placing an intravenous cannula through a scleral tunnel into the anterior chamber. Rabbits were examined at set intervals for up to 30 days after surgery. Measurements of appearance, size, height, and vascularity of blebs and of intraocular pressure and anterior chamber depth were made by a masked observer. Histologic analysis of eyes was performed at 3, 14, and 30 days.
Statistical analysis showed a significant difference in bleb survival among all groups (log rank P = 0.0054, with 100% survival with large areas of MMC treatment). Comparison between large and small treatment area groups revealed significant differences in bleb survival (log rank P = 0.0388); bleb area (between-subject analysis, P = 0.009), and bleb height (between-subject analysis, P = 0.005). These differences were seen clinically, with large areas of MMC treatment producing diffuse and elevated blebs, small areas of treatment producing thin-walled and localized blebs with scarring at 21 days, and no treatment resulting in comparatively vascularized and scarred blebs before 14 days. Histologic analysis revealed clear differences among groups, with an increase in subconjunctival cellularity and scar tissue in eyes with failed blebs.
The size of the area of subconjunctival MMC treatment significantly affects surgical outcome. Histologic features mirror differences observed clinically. Alteration of the size of the MMC treatment area may provide an alternative and more controllable approach to modulating the wound-healing response after drainage surgery and, more important in the clinical context, to modifying bleb morphology.
利用改良的兔滤过手术模型，研究结膜下应用丝裂霉素C（MMC）时改变治疗面积的效果。
24只新西兰白兔接受滤过手术，随机分为三组接受以下三种治疗之一：用大（8×10毫米）或小（4×2毫米）海绵结膜下应用MMC（0.4毫克/毫升）5分钟，或不治疗（对照组）。通过将静脉套管经巩膜隧道置入前房来实现引流。术后每隔一定时间对兔子进行检查，最长至30天。由一位不知情的观察者对滤过泡的外观、大小、高度和血管化情况以及眼压和前房深度进行测量。在术后3天、14天和30天对眼睛进行组织学分析。
统计分析显示所有组之间滤过泡存活情况存在显著差异（对数秩检验P = 0.0054，大面积MMC治疗组滤过泡存活率为100%）。大面积与小面积治疗组之间的比较显示，滤过泡存活情况（对数秩检验P = 0.0388）、滤过泡面积（受试者间分析，P = 0.009）和滤过泡高度（受试者间分析，P = 0.005）存在显著差异。这些差异在临床上可见，大面积MMC治疗产生弥漫性且隆起的滤过泡，小面积治疗产生薄壁且局限的滤过泡，在21天时出现瘢痕形成，而不治疗则导致在14天前滤过泡相对血管化且有瘢痕形成。组织学分析显示各组之间存在明显差异，滤过泡失败的眼睛结膜下细胞增多和瘢痕组织增加。
结膜下MMC治疗面积的大小显著影响手术结果。组织学特征反映了临床上观察到的差异。改变MMC治疗面积的大小可能为调节引流手术后的伤口愈合反应提供一种替代且更可控的方法，在临床背景下更重要的是，可改变滤过泡形态。
