■基质内角膜环节段通常植入轻度至中度圆锥角膜眼的角膜中;然而,植入后角膜密度测定(CD)的变化在当前文献中存在争议。我们评估了飞秒激光辅助角膜缘植入后1和3个月CD的变化。
■这次回顾展,非比较性,多中心,病例系列研究包括接受飞秒激光辅助植入90°和160°弧长双节段或两个160°弧长角膜段的圆锥角膜患者。记录人口统计学和基线临床眼科数据。使用PentacamHRScheimpflug层析成像系统采集的角膜地形图和层析成像数据(Pentacam高分辨率;Oculus,Wetzlar,德国)具有最佳拟合球体作为参考表面。使用PentacamHR,CD测量是在总共12毫米的角膜区域以及三个角膜基质深度的四个同心区域(0-2、2-6、6-10和10-12毫米)上进行的:前角膜基质层120μm,角膜后基质层60μm,基质的中间层位于这两层之间。
■我们包括40名患者的40只眼睛,包括8名(20%)男性和32名(80%)女性,平均(标准差)年龄为21.0(6.4)岁。我们观察到陡峭角膜曲率测量(K)的地形值显着改善,平K,最大K,角膜散光(均P<0.05),但不是在意思K,最薄的角膜测厚仪,角膜先端厚度,后高程,或前立面图(均P>0.05)。平均总前部,中央,后CD在时间点之间存在显着差异,从术前到术后1个月和3个月的访视次数显着增加(均P<0.05),而术后1个月和3个月的访视次数无差异(均P>0.05)。中央前层的平均CD,paracentral,和中间外围区域,和所有四个区域的中间层,不同时间点之间存在显著差异,从术前到术后1个月和3个月的访视次数显着增加(均P<0.05),术后1个月至3个月随访均无变化(P均<0.05),除了中央的2-6毫米区域,从术后1个月到3个月的访视显着降低(P<0.001)。中心10-12-mm区的CD在每个成对比较中没有显着差异(均P>0.05)。相比之下,从术前到术后1个月和3个月,中央旁区域后层的CD显着降低,但增加,在较小程度上,术后1个月至3个月随访(均P<0.05)。
■飞秒激光辅助Keraring植入显著改变CD,改善大多数地形参数。需要更大样本量的进一步纵向研究来验证这些初步发现。
UNASSIGNED: Intrastromal corneal ring segments are commonly implanted in the corneas of eyes with mild-to-moderate keratoconus; however, changes in corneal densitometry (CD) after implantation are a matter of debate in the current literature. We evaluated the changes in CD 1 and 3 months after femtosecond laser-assisted Keraring implantation.
UNASSIGNED: This retrospective, non-comparative, multicenter, case series study included patients with keratoconus who underwent femtosecond laser-assisted implantation of double segments with 90° and 160° arc lengths or two 160° arc length Keraring segments. Demographic and baseline clinical ophthalmic data were recorded. Corneal topography and tomography data acquired using a Pentacam HR Scheimpflug tomography system (Pentacam High Resolution; Oculus, Wetzlar, Germany) with a best-fit sphere were used as a reference surface. Using the Pentacam HR, CD measurements were acquired over a corneal area of 12 mm in total and at four concentric zones (0-2, 2-6, 6-10, and 10-12 mm) of three corneal stromal depths: 120 μm of the anterior corneal stromal layer, 60 μm of the posterior corneal stromal layer, and the central layer of stroma lying between these two layers.
UNASSIGNED: We included 40 eyes of 40 patients, including 8 (20%) male and 32 (80%) female individuals, with a mean (standard deviation) age of 21.0 (6.4) years. We observed a significant improvement in the topographic values of steep keratometry (K), flat K, maximum K, and corneal astigmatism (all P < 0.05), but not in the mean K, thinnest corneal pachymetry, corneal thickness at the apex, back elevation, or front elevation (all P > 0.05). The mean total anterior, central, and posterior CD differed significantly among the time points, with a significant increase from the preoperative to the 1-month and 3-month postoperative visits (all P < 0.05) and no difference between those of the 1-month and 3-month postoperative visits (all P > 0.05). The mean CD for the anterior layer in the central, paracentral, and mid-peripheral zones, and the central layer in all four zones, differed significantly among time points, with a significant increase from the preoperative to the 1-month and 3-month postoperative visits (all P < 0.05), which remained unchanged from the 1-month to the 3-month postoperative visit (all P < 0.05), except for the central 2-6-mm zone, which decreased significantly from the 1-month to the 3-month postoperative visit (P < 0.001). The CD of the central 10-12-mm zone did not differ significantly in each pairwise comparison (all P > 0.05). In contrast, CD for the posterior layer in the paracentral zone decreased significantly from the preoperative to the 1-month and 3-month postoperative visits but increased, to a lesser extent, from the 1-month to the 3-month postoperative visit (all P < 0.05).
UNASSIGNED: Femtosecond laser-assisted Keraring implantation significantly changes CD, with improvement in most topography parameters. Further longitudinal studies with larger sample sizes are required to verify these preliminary findings.