Ghanem Ramon Coral, Ghanem Emir Amin, Kara-José Newton
Departamento de Oftalmologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil.
Arq Bras Oftalmol. 2010 Mar-Apr;73(2):165-70. doi: 10.1590/s0004-27492010000200013.
To evaluate the safety of photorefractive keratectomy (PRK) with mitomycin-C (MMC) in eyes with hyperopia after radial keratotomy.
Sixty eyes of 36 consecutive patients treated with corneal wavefront-guided PRK using an Esiris-Schwind excimer laser were prospectively evaluated. Corneal epithelium was mechanically removed, followed by photoablation and use of 0.02% MMC for 20 or 40 seconds. In 16 eyes (26.7%), MMC was applied for 40 seconds. These eyes underwent ablations deeper than 100 micron or had previous corneal sutures. Patients were followed up for 12 months.
The mean spherical equivalent (SE) before PRK was +4.27 D +/- 2.18, and the mean best corrected visual acuity (BCVA) was 0.174 +/- 0.139 (logMAR). The planned laser SE correction was +4.74 D +/- 2.11, resulting in an ablation depth of 78 +/- 28 microm (from 33 to 148). No intraoperative complications were observed. At one year, mean SE was +0.04 D +/- 1.03 (p<0.001) and mean BCVA was 0.079 +/- 0.105 (p<0.001). There was a gain of 2 or more lines of BCVA in 20 eyes (33.3%) and only one eye (1.7%) lost 2 lines. Correlation analysis showed that the improvement in BCVA was inversely related to preoperative BCVA (r=-0.694; p<0.001). Five eyes developed peripheral haze grade 2 or 3 and one eye had central trace haze. No significant correlation was found between central or peripheral haze and the number of radial incisions, depth of the ablation or postoperative BCVA. Mean preoperative endothelial cell count was 2,681 +/- 455 cel/ mm(2) and after one year was 2,481 +/- 378 cel/mm(2) (p=0.124). One eye developed keratectasia due to the progressive widening of an inferior radial incision, which was later sutured.
PRK with MMC was safe after one year of follow-up for the reduction of hyperopia after radial keratotomy. A major improvement in BCVA was obtained with a small incidence of haze and other complications.
评估在放射状角膜切开术后远视眼中使用丝裂霉素-C（MMC）的准分子激光原位角膜磨镶术（PRK）的安全性。
前瞻性评估连续36例患者的60只眼，这些眼使用艾西丽斯-施温德准分子激光进行角膜波前引导的PRK治疗。机械去除角膜上皮，随后进行光消融，并使用0.02%的MMC 20或40秒。16只眼（26.7%）使用MMC 40秒。这些眼的消融深度超过100微米或之前有角膜缝线。患者随访12个月。
PRK术前平均等效球镜度（SE）为+4.27 D±2.18，平均最佳矫正视力（BCVA）为0.174±0.139（logMAR）。计划的激光SE矫正为+4.74 D±2.11，消融深度为78±28微米（范围33至148）。未观察到术中并发症。1年后，平均SE为+0.04 D±1.03（p<0.001），平均BCVA为0.079±0.105（p<0.001）。20只眼（33.3%）的BCVA提高了2行或更多，仅1只眼（1.7%）视力下降2行。相关性分析显示，BCVA的改善与术前BCVA呈负相关（r=-0.694；p<0.001）。5只眼出现2级或3级周边混浊，1只眼有中央微量混浊。中央或周边混浊与放射状切口数量、消融深度或术后BCVA之间未发现显著相关性。术前平均内皮细胞计数为每平方毫米2,681±455个细胞，1年后为每平方毫米2,481±378个细胞（p=0.124）。1只眼因下方放射状切口逐渐增宽而发生角膜扩张，随后进行了缝合。
在放射状角膜切开术后远视眼中，随访1年显示使用MMC的PRK在降低远视方面是安全的。BCVA有显著改善，混浊和其他并发症的发生率较低。
