Oregon Health and Science University, Portland, OR, USA.
Cornea. 2013 Jan;32(1):54-62. doi: 10.1097/ICO.0b013e31825ea2e6.
To use beveled femtosecond laser astigmatic keratotomy (FLAK) incisions to treat high astigmatism after penetrating keratoplasty.
Paired FLAK incisions at a bevel angle of 135 degrees, 65% to 75% depth, and arc lengths of 60 to 90 degrees were performed using a femtosecond laser. One case of perpendicular FLAK was presented for comparison. Vector analysis was used to calculate the changes in astigmatism. Fourier domain optical coherence tomography was used to examine incision morphology.
Wound gaping requiring suturing was observed in the case of perpendicular FLAK. Six consecutive cases of beveled FLAK were analyzed. Fourier domain optical coherence tomography showed that beveled FLAK caused a mean forward shift of Bowman layer anterior to the incisions of 126 ± 38 μm, with no wound gaping. The mean magnitude of preoperative keratometric astigmatism was 9.8 ± 2.9 diopters (D), and postoperatively it was 4.5 ± 3.2 D (P < 0.05). Uncorrected visual acuity improved from 1.24 ± 0.13 logarithm of the minimum angle of resolution preoperatively to 0.76 ± 0.38 postoperatively (P < 0.05). Best spectacle-corrected visual acuity improved from 0.43 ± 0.33 logarithm of the minimum angle of resolution preoperatively to 0.27 ± 0.24 postoperatively (P = 0.22). Visual results were reduced in 2 patients by cataract progression. Between 1 and 3 months after beveled FLAK, the keratometric cylinder was stable (<1 D change) in 5 of 6 patients, and regressed in 1 patient. No complications occurred.
Beveled FLAK incisions at varied depth are effective in the management of postkeratoplasty astigmatism. Early postoperative changes stabilized within 1 month in most patients. Further studies are needed to assess long-term outcomes.
使用斜角飞秒激光散光性角膜切开术（FLAK）切口治疗穿透性角膜移植术后的高度散光。
使用飞秒激光进行 135 度斜角、65%至 75%深度和 60 至 90 度弧形长度的配对 FLAK 切口。为了进行比较，提出了一个垂直 FLAK 的案例。使用向量分析来计算散光的变化。傅里叶域光学相干断层扫描用于检查切口形态。
垂直 FLAK 出现了需要缝合的伤口张开。对 6 例连续的斜角 FLAK 进行了分析。傅里叶域光学相干断层扫描显示，斜角 FLAK 导致切口前 Bowman 层向前平均移动 126±38μm，没有伤口张开。术前角膜散光的平均大小为 9.8±2.9 屈光度（D），术后为 4.5±3.2 D（P<0.05）。未矫正视力从术前的 1.24±0.13 最小角分辨率对数提高到术后的 0.76±0.38（P<0.05）。最佳矫正视力从术前的 0.43±0.33 最小角分辨率对数提高到术后的 0.27±0.24（P=0.22）。2 名患者因白内障进展导致视力结果降低。在斜角 FLAK 后 1 至 3 个月，6 名患者中有 5 名的角膜散光柱稳定（<1 D 变化），1 名患者的散光柱回归。没有发生并发症。
斜角 FLAK 切口在不同深度下对处理角膜移植术后散光有效。大多数患者在术后 1 个月内，术后早期变化稳定。需要进一步研究来评估长期结果。
