El-Ashry Mohamed, Appaswamy Shivashankar, Deokule Sunil, Pagliarini Sergio
Paybody Eye Unit, Coventry and Warwickshire University Hospital NHS Trust, Coventry, UK.
Curr Eye Res. 2006 May;31(5):409-13. doi: 10.1080/02713680600646882.
To evaluate whether the measurement of retinal nerve fiber layer (RNFL) thickness using optical coherence tomography (OCT) changes after cataract surgery.
This prospective, randomized, observational, cross-sectional clinical study included 24 eyes of 24 patients who underwent phacoemusification with implant. All patients had no preexisting retinal or optic nerve pathology or other media opacities that might influence the RNFL thickness. The classification and the grading of cataract were based on the Lens Opacities Classification System III (LOCS III). All eyes were scanned immediately before cataract surgery with OCT using Fast RNFL program. All eyes had circular scans around the optic disk with a diameter of 3.4 mm. The OCT was repeated 4 weeks after surgery when the patients returned for postoperative check using the same programme.
The mean preoperative RNFL thickness was 84.9 +/- 16.5. The postoperative mean RNFL thickness was 93.0 +/- 17.6. The pre-and postoperative values of the mean RNFL and signal/noise ratio (SNR) are statistically significant (P < 0.05).
Lens opacities may affect the image quality of OCT scans used to measure RNFL thickness as indicated by preoperative low SNR. Cataract extraction results in an apparent increase of the RNFL thickness.
评估白内障手术后使用光学相干断层扫描（OCT）测量视网膜神经纤维层（RNFL）厚度是否会发生变化。
这项前瞻性、随机、观察性横断面临床研究纳入了24例接受白内障超声乳化联合人工晶状体植入术患者的24只眼。所有患者术前均无视网膜或视神经病变，也无其他可能影响RNFL厚度的眼内介质混浊。白内障的分类和分级基于晶状体混浊分类系统III（LOCS III）。所有眼睛在白内障手术前立即使用快速RNFL程序进行OCT扫描。所有眼睛均围绕视盘进行直径为3.4 mm的环形扫描。术后4周患者复诊时，使用相同程序再次进行OCT检查。
术前RNFL平均厚度为84.9±16.5。术后RNFL平均厚度为93.0±17.6。术前和术后RNFL平均值及信噪比（SNR）差异有统计学意义（P<0.05）。
如术前低SNR所示，晶状体混浊可能会影响用于测量RNFL厚度的OCT扫描图像质量。白内障摘除术后RNFL厚度明显增加。
