Maldonado M J
Department of Ophthalmology, Albacete General Hospital, Valencia, Spain.
Ophthalmology. 1998 Aug;105(8):1546-9. doi: 10.1016/S0161-6420(98)98045-9.
This study aimed to describe a previously unreported complication associated with the use of chlorine-disinfected applanation tonometer heads for intraocular pressure measurement after excimer laser photorefractive keratectomy.
Two retrospective case reports.
Two patients underwent, respectively, a 7-diopter and a 4-diopter myopic excimer laser correction in their first eye 2 weeks apart. Complete epithelial closure of the ablated area was observed by biomicroscopy in the first-week examination.
Four weeks after photorefractive keratectomy, a complete ophthalmic examination was performed. Goldmann applanation tonometry was performed bilaterally after thoroughly rinsing and drying the tonometer biprism, which had been immersed regularly in a chlorine 5000-parts per million solution.
Slit-lamp examination and corneal topographic surface regularity were measured.
A few minutes after applanation tonometry, both patients reported ocular discomfort in the excimer laser-treated eyes, whereas the untreated fellow eyes were painless. Punctate corneal lesions and superficial epithelial cell clumping were present in the first patient's treated eye, predominantly in the inferior aspect of the applanated cornea. Visual inspection showed a normal tonometer tip. In the second patient's treated cornea, a focal epithelial defect was identified biomicroscopically, which corresponded to the steeper region within the ablation zone on the videokeratograph. In this case, crystal deposits were found on the tonometer tip. The epithelial alterations resolved without sequelae in both cases.
Disinfecting solutions of chlorine can cause crystal deposit formation on the tonometer head. Applanation tonometry after repeated disinfection with chlorine solutions appears to have the potential for disrupting the epithelial layer of the healing cornea. Covered contact tonometry or noncontact tonometry should be evaluated as alternative methods to chemically disinfected contact tonometry for intraocular pressure measurement after excimer laser surgery, especially during the first postoperative month.
本研究旨在描述一种与使用经氯消毒的压平眼压计探头测量准分子激光屈光性角膜切削术后眼压相关的、此前未报道的并发症。
两项回顾性病例报告。
两名患者分别在相隔2周的时间里对其第一眼进行了7屈光度和4屈光度的近视准分子激光矫正。在第一周检查时通过生物显微镜观察到消融区域上皮完全愈合。
准分子激光角膜切削术后4周进行全面的眼科检查。在将眼压计双棱镜彻底冲洗并干燥后双侧进行Goldmann压平眼压测量，该双棱镜定期浸泡在百万分之5000的氯溶液中。
测量裂隙灯检查结果及角膜地形图表面规则性。
压平眼压测量后几分钟，两名患者均报告准分子激光治疗眼有眼部不适，而未治疗的对侧眼无痛。第一名患者的治疗眼中存在点状角膜病变和浅表上皮细胞聚集，主要位于压平角膜的下方。肉眼检查显示眼压计探头正常。在第二名患者的治疗角膜中，通过生物显微镜检查发现一处局限性上皮缺损，其对应于角膜地形图上消融区内较陡的区域。在该病例中，眼压计探头上发现有晶体沉积物。两例患者的上皮改变均未遗留后遗症而自行消退。
氯消毒溶液可导致眼压计探头上形成晶体沉积物。用氯溶液反复消毒后进行压平眼压测量似乎有可能破坏愈合中角膜的上皮层。对于准分子激光手术后眼压测量，尤其是在术后第一个月，应评估使用覆盖式接触眼压测量法或非接触眼压测量法作为化学消毒接触眼压测量法的替代方法。
