Januleviciene Ingrida, Sliesoraityte Ieva, Siesky Brent, Harris Alon
Kaunas Eye Clinic, University of Medicine, Kaunas, Lithuania.
Acta Ophthalmol. 2008 Aug;86(5):552-7. doi: 10.1111/j.1600-0420.2007.01091.x. Epub 2007 Dec 11.
Current evidence indicates that alteration in ocular blood flow may be relevant in open-angle glaucoma (OAG) patients independent of intraocular pressure (IOP). Presently, the lack of an adequate methodology capable of assessing all vascular beds limits the clinical role of blood flow parameters in glaucoma management. We aimed to compare differences in retinal nerve fibre layer (RNFL) thickness and retrobulbar haemodynamics between OAG patients and healthy age-matched control subjects.
Sixty eyes of 30 OAG patients and 30 healthy age-matched controls were enrolled into the prospective, randomized study. Retinal nerve fibre layer thickness was analysed by scanning laser polarimetry (SLP). Standard SLP parameters were determined, including: average temporal, superior, nasal, inferior thickness (TSNIT); superior and inferior averages; TSNIT standard deviation (TSNIT-SD), and nerve fibre indicator (NFI). Retrobulbar haemodynamics were assessed using colour Doppler imaging (CDI). Peak systolic velocity (PSV), end-diastolic velocity (EDV), pulsatility index (PI) and resistivity index (RI) in the ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary artery (SPCA) were evaluated.
The RNFL in OAG patients was statistically significantly thinner compared with that in age-matched controls: the NFI was 24.9 +/- 10.24 in OAG patients and 16.13 +/- 7.95 in healthy controls (p < 0.05). Statistically significant differences were observed: CRA PSV was 20.54 +/- 7.84 cm/second in OAG subjects and 16.5 +/- 6.19 cm/second in healthy controls (p = 0.0038); OA EDV was 8.99 +/- 4.71 cm/second in OAG subjects and 5.93 +/- 3.23 cm/second in healthy controls (p = 0.0048). Correlation analysis of NFI was in positive association with CRA EDV (r = 0.395; p < 0.05) and CRA PI (r = 0.403; p < 0.05) in OAG subjects, but no statistically significant association was seen in healthy controls.
Statistically significant thinning of the RNFL in association with reduced retrobulbar blood flow velocities was observed in OAG patients. Combining ocular structural alterations with ocular circulation assessment may increase our ability to elucidate potential IOP-independent glaucomatous risk factors.
目前的证据表明，眼血流改变可能与开角型青光眼（OAG）患者相关，且独立于眼压（IOP）。目前，缺乏一种能够评估所有血管床的适当方法限制了血流参数在青光眼管理中的临床作用。我们旨在比较OAG患者与年龄匹配的健康对照者之间视网膜神经纤维层（RNFL）厚度和球后血流动力学的差异。
30例OAG患者的60只眼和30例年龄匹配的健康对照者纳入了这项前瞻性随机研究。通过扫描激光偏振仪（SLP）分析视网膜神经纤维层厚度。确定标准的SLP参数，包括：颞侧、上方、鼻侧、下方平均厚度（TSNIT）；上方和下方平均值；TSNIT标准差（TSNIT-SD）以及神经纤维指数（NFI）。使用彩色多普勒成像（CDI）评估球后血流动力学。评估眼动脉（OA）、视网膜中央动脉（CRA）和睫状后短动脉（SPCA）的收缩期峰值速度（PSV）、舒张末期速度（EDV）、搏动指数（PI）和阻力指数（RI）。
与年龄匹配的对照者相比，OAG患者的RNFL在统计学上显著变薄：OAG患者的NFI为24.9±10.24，健康对照者为16.13±7.95（p<0.05）。观察到统计学上的显著差异：OAG受试者的CRA PSV为20.54±7.84厘米/秒，健康对照者为16.5±6.19厘米/秒（p=0.0038）；OAG受试者的OA EDV为8.99±4.71厘米/秒，健康对照者为5.93±3.23厘米/秒（p=0.0048）。在OAG受试者中，NFI的相关性分析与CRA EDV呈正相关（r=0.395；p<0.05）以及与CRA PI呈正相关（r=0.403；p<0.05），但在健康对照者中未观察到统计学上的显著相关性。
在OAG患者中观察到RNFL在统计学上显著变薄，同时球后血流速度降低。将眼部结构改变与眼循环评估相结合可能会提高我们阐明潜在的独立于眼压的青光眼危险因素的能力。
