Effect of Platelet-Rich Plasma on Corneal Epithelial Healing after Phototherapeutic Keratectomy: An Intraindividual Contralateral Randomized Study

Purpose. To assess the effect of platelet-rich plasma (PRP) on the healing response of the corneal epithelium in eyes undergoing phototherapeutic keratectomy (PTK). Methods. We prospectively examined 20 eyes of 10 patients undergoing bilateral PTK for granular corneal dystrophy or band keratopathy. Patients were randomly assigned to start topical administration of PRP ophthalmic suspension (PRP group) or artificial tears (control group) 4 times daily for 2 weeks. Immediately, 1, and 2 days, and 1 week after PTK, we quantitatively measured the staining area of the corneal epithelium, using slit-lamp photography. We also determined the subjective symptoms and the satisfaction, using the visual analogue system (VAS). Results. The staining area in the PRP group was significantly smaller than that in the control group on days 1 and 2 (Wilcoxon signed-rank test, p = 0.022 and p = 0.017 , respectively), but not on day 7 ( p = 0.317 ). The recovery rate of the corneal epithelium in the PRP group was significantly higher than that in the control group on days 1 and 2 ( p = 0.022 and p = 0.017 , respectively), but not on day 7 ( p = 0.317 ). We found no significant differences in pain ( p = 0.139 ), foreign body sensation ( p = 0.108 ), epiphora ( p = 1.000 ), or satisfaction ( p = 0.295 ), between the two groups. Postoperative complications did not occur in any of the eyes in the study. Conclusions. The PRP treatment was effective for enhancing corneal epithelial recovery in the early postoperative period, without significant adverse events, in post-PTK-treated eyes, suggesting that it may hold promise as one of the treatment options for treating such postsurgical patients.

Case Report: Phototherapeutic Keratectomy for Band Keratopathy Secondary to Chemo-Laser-Cryotherapy for Retinoblastoma

Purpose: To report the clinical outcomes of phototherapeutic keratectomy (PTK) for pediatric band keratopathy after treatment for retinoblastoma.Methods: A 5-year-old boy presented with a 2-year history of poor visual acuity and a horizontal gray-white band across the central cornea in the right eye. He was diagnosed with band keratopathy after chemo-laser-cryotherapy for retinoblastoma. The band keratopathy was treated via PTK using the Mel-90 excimer laser with an optical treatment zone of 7.0 mm and ablation depth of 120 μm. The patient was followed at 1 week and 3 months postoperatively.Results: Surgery and postoperative follow-up were uneventful. At the 3-month follow-up, the uncorrected distant visual acuity of the right eye improved to 20/125, and the corrected distance visual acuity improved to 20/70 with a refraction of +10.00 D/−2.50 DC × 15. The clarity of the ablated area was evidently improved. The central corneal thickness decreases from 612 to 584 μm. The optical coherence tomography showed the thin band of hyperreflectivity in the ablated area disappeared, corneal transparency improved and the corneal surface smoothened.Conclusions: PTK is a safe and effective procedure to treat band keratopathy following treatment of retinoblastoma in children. Early intervention can reduce the risk of developing deprivation amblyopia.

Surgical outcomes of re-excimer laser phototherapeutic keratectomy (re-PTK)

To assess the surgical outcomes of re-excimer laser phototherapeutic keratectomy (re-PTK) for recurrent disease after initial PTK. Retrospective cohort study with historical comparison group. This study involved 56 patients who underwent re-PTK (mean follow-up period: 47.9 ± 36.2 months) at the Baptist Eye Institute, Kyoto, Japan. In all subjects, corrected-distance visual acuity (CDVA) before and after re-PTK was compared. Postoperative recurrence of corneal lesion with a decrease of CDVA of two lines or more was compared with postoperative best CDVA deemed as a significant relapse. The Kaplan–Meier method was used to compare the recurrence rate post-re-PTK with that after the initial PTK. The disease classification in the 78 eyes was heterozygous-type GCD (hetero-GCD, n = 47 eyes), homozygous-type GCD (homo-GCD, n = 13 eyes), band keratopathy (n = 7 eyes), lattice corneal dystrophy (n = 6 eyes), and other (n = 5 eyes). After re-PTK, homo-GCD recurred statistically significantly earlier than hetero-GCD (P = 0.0042). No significant difference was found in the recurrence rate for all diseases between post-re-PTK and post initial PTK (P > 0.05). Surgical outcomes after re-PTK were nearly equal to those after initial-PTK.

Clinical outcomes of simultaneous phototherapeutic keratectomy and photoastigmatic keratectomy

This study was aimed to assess the outcomes of simultaneous phototherapeutic keratectomy (PTK) and photoastigmatic keratectomy (PAK), with special attention to astigmatic correction. We comprised 70 eyes of 70 patients who underwent simultaneous PTK and PAK in patients having granular corneal dystrophy and band keratopathy with refractive astigmatism of 1 diopter (D) or more. Preoperatively and 6 months postoperatively, we assessed corrected uncorrected distance visual acuity (UDVA), distance visual acuity (CDVA), manifest spherical equivalent, refractive astigmatism, corneal astigmatism, and higher-order aberrations (HOAs). LogMAR CDVA significantly improved, from 0.27 ± 0.27 preoperatively, to 0.13 ± 0.21 postoperatively (Paired t test, p < 0.001). LogMAR UDVA also significantly improved, from 0.70 ± 0.32 preoperatively, to 0.57 ± 0.41 postoperatively (p = 0.043). Refractive astigmatism significantly decreased, from 2.12 ± 0.95 D preoperatively, to 0.89 ± 0.81 D postoperatively (p < 0.001). Corneal astigmatism also significantly decreased, from 2.17 ± 0.90 D preoperatively, to 1.08 ± 0.71 D postoperatively (p < 0.001). Corneal HOAs did not significantly change, from 0.54 ± 0.30 µm preoperatively, to 0.48 ± 0.20 µm postoperatively (p = 0.140). No significant complications occurred in any eye. Simultaneous PTK and PAK treatment is effective not only for improving visual acuity, but also for reducing astigmatism.