To comprehensively review the available published literature for cross-linking in the pediatric population.
Review of the literature published in English in PubMed.
Two hundred ten publications were ...considered. One hundred fifteen were considered relevant to this review.
Studies of cross-linking in pediatric patients are sparse, with relatively short follow-up times, and mostly on small groups of patients. Treatment with cross-linking halts progression of keratoconus in the pediatric population, and early treatment seems to be cost-effective compared with later penetrating keratoplasty. Long-term effects and regression rates remain unclear, and further studies are needed in this population.
The aim of this study was to estimate the efficacy of intense pulsed light (IPL), followed by meibomian gland expression (MGX), for reducing the number and severity of signs and symptoms of dry eye ...disease (DED) secondary to meibomian gland dysfunction (MGD).
In a prospective study conducted in two sites, 40 subjects (80 eyes) with moderate to severe MGD were enrolled. Major inclusion criteria consisted of at least two of the following measures being compatible with DED in both eyes: tear breakup time (TBUT), meibomian gland score (MGS), corneal fluorescein staining (CFS), Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire, and tear film osmolarity (TFO). Enrolled patients underwent four treatment sessions, 3 weeks apart. Each treatment included the administration of 10-15 pulses of IPL on the cheeks and nose, followed by MGX of the upper and lower eyelids. TBUT, MGS, CFS, SPEED, TFO, and lipid layer thickness (LLT) were measured at baseline (BL) and at 9, 12, and 15 weeks after BL.
Due to different staining methods used for TBUT measurements, TBUT and CFS were analyzed separately for each site. From BL to the final follow-up, the number of signs compatible with DED decreased from 3.3±0.1 to 1.4±0.1. TBUT improved by +93% (n=38;
<0.0001) and +425% (n=42;
<0.0001) for sites 1 and 2, respectively. SPEED, MGS, and CFS improved by -55% (n=80;
<0.0001), -36% (n=80;
<0.0001), and -58% (n=38;
<0.0001), respectively. In 20 eyes with abnormally elevated TFO at BL, TFO improved by -7% (n=20;
<0.005). LLT did not change (n=38;
=0.88).
In subjects with moderate to severe MGD, IPL combined with MGX reduced the number and severity of symptoms and signs of DED. Except for LLT, all examined outcome measures significantly improved after 15 weeks. These results support the efficacy of IPL + MGX in relieving both signs and symptoms of DED secondary to MGD.
•Corneal collagen crosslinking (CXL) is a safe and effective way of stabilizing corneal ectasia induced by LASIK (post-LASIK ectasia, PLE).•These data were previously shown to be true during a ...shorter post-operative period (less than five years) or among fewer patients.•CXL for PLE is now known to be safe and effective for up to five years after the procedure in a large sample size.•This paper re-affirms that CXL could be considered for patients with progressive refractive changes after LASIK.
To evaluate the safety and efficacy of epithelium-off (epi‑off) corneal cross-linking (CXL) in patients with post-LASIK corneal ectasia (PLE)
Private clinical practice
Prospective clinical trial
82 eyes of adult patients post-LASIK, ages 21–67, with a topography pattern consistent with corneal ectasia, corrected distance visual acuity (CDVA) worse than 20/20, and minimum corneal pachymetry > 400 µm underwent epi‑off CXL. Exclusion criteria were patients with corneas that were thinner than 400 μm or demonstrated central corneal scarring, history of herpetic eye disease, pregnancy or nursing. Follow up examinations of spherical equivalent, uncorrected distance visual acuity (UDVA), CDVA, steep keratometry (KSteep) and minimum pachymetry occurred on different but highly overlapping subsets of the operated eyes yearly until 5 years post-CXL.
Over the 5 years of follow up, spherical equivalent did not significantly change while UCVA and CDVA stabilized or improved to a non-significant degree. KSteep and minimum pachymetry continued to be decreased to a statistically significant degree (p < 0.05 at 5 years).
CXL in PLE patients is safe and efficacious: it halts progression of PLE and may improve visual function. KSteep and minimum pachymetry decrease post-CXL. Patients with PLE should be encouraged to stop progression of the disease by undergoing epi‑off CXL once progression is established.
This paper will compare the visual outcomes of two different penetrating keratoplasty (PKP) techniques in patients with keratoconus. It is a retrospective comparative surgical case series of 116 ...keratoconus patients (137 eyes) who had PKP at the Cornea Eye Institute, Beverly Hills, California, USA.
56 keratoconus patients (66 eyes) underwent femtosecond laser-enabled keratoplasty (FLEK) with a zig-zag incision configuration. Their visual parameters were compared with those of 60 patients (71 eyes) who had traditional blade mechanical trephination PKP. The range of follow-up was between 3 and 6 months. The main outcome measures included uncorrected visual acuity and best spectacle-corrected visual acuity (BSCVA), manifest refractive spherical equivalent and topographically determined astigmatism.
BSCVA was significantly better as early as 3 months postoperatively (p=0.001) in the FLEK group. Visual recovery to 20/40 after 3 months was significantly better in the FLEK group (p<0.001). Topographic astigmatism was lower in the FLEK group, but the difference between the two groups reached significance only at 3 months of follow-up (p=0.001). Postoperative complications noted were not different between the two groups.
Faster visual recovery and better long-term outcomes were observed in keratoconus patients who had FLEK compared with those who had the mechanical PKP procedure with 6 months of postoperative follow-up.
To compare the visual, refractive, keratometric, topographic, and pachymetric outcomes of corneal collagen cross-linking (CXL) for progressive keratoconus following epithelial removal by ...transepithelial phototherapeutic keratectomy (PTK) or manual debridement.
In this analysis, 339 eyes (78% male, 22% female) that had undergone CXL following manual epithelial debridement (n = 180) or ablation via PTK (n = 159) were evaluated preoperatively and at 6, 12, and 24 months postoperatively for uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), maximum corneal keratometry, pachymetry, and spherical equivalent. The data were analyzed in a t test to evaluate the relative efficacy of each epithelial removal procedure.
Manual epithelial debridement and ablation via PTK produce equivalent changes for all variables at each time interval with the exception of maximum corneal keratometry at 6 months postoperatively, for which PTK exhibited a significantly improved (flatter) result. This difference was present but not statistically significant at 12 and 24 months postoperatively.
Prior to CXL, both manual epithelial debridement and ablation via PTK result in equivalent visual, refractive, and keratometric outcomes up to 24 months postoperatively. J Refract Surg. 2016;32(10):699-704..
To evaluate visual outcomes and astigmatism in patients who underwent penetrating keratoplasty (PK) with 2 different incision techniques.
Retrospective comparison of a consecutive surgical series.
...Fifty-seven consecutive patients who underwent PK at the University of California, Irvine, academic referral practice.
A comparison of 49 eyes of 43 patients that underwent femtosecond laser zig-zag incision pattern PK versus 17 eyes of 14 patients that underwent conventional Barron suction trephination PK performed contemporaneously. All PKs were closed with an identical, 24-bite running nylon suture technique.
Topographically determined astigmatism, best spectacle-corrected visual acuity (BSCVA), and recovery of full visual potential.
The postoperative follow-up ranged from 1 to 12 months. There was a significant difference in average astigmatism between the groups at postoperative month 1 (P = 0.013) and 3 (P = 0.018). By month 3, the average astigmatism was 3 diopters (D) in the zig-zag group and 4.46 D in the conventional group. Of the patients with normal macular and optic nerve function (n(ZZ) = 32; n(con) = 14), a significant difference in BSCVA was seen at month 1 (P = 0.0003) and month 3 (P = 0.006) with 81% of the zig-zag group versus 45% of the conventional group achieving BSCVA of > or =20/40 by month 3 (P = 0.03).
The femtosecond laser generated zig-zag-shaped incision results in a more rapid recovery of BSCVA and induces less astigmatism compared with conventional blade trephination PK.
Proprietary commercial disclosure may be found after the references.
To evaluate and compare corneal higher-order aberrations (HOAs) after Descemet stripping automated endothelial keratoplasty (DSAEK), femtosecond laser-assisted penetrating keratoplasty (FLAK), and ...conventional penetrating keratoplasty (PKP).
A retrospective comparison of consecutive surgical series of 67 eyes of 59 patients between 1.5 and 19 months after corneal transplant surgery (22, 34, and 11 corneas underwent DSAEK, FLAK, and PKP, respectively, by a single surgeon). The main outcome measures were anterior and posterior corneal surface HOAs (Zernike polynomials, third to eighth order) determined with Scheimpflug photography at 4.0- and 6.0-mm optical zones and best spectacle-corrected visual acuity (BSCVA) (logarithm of the minimum angle of resolution equivalents).
DSAEK had fewer total anterior HOAs compared with FLAK P = 5.27 × 10(-5) (4.0 mm) and P = 1.02 × 10(-5) (6.0 mm) and PKP P = 1.82 × 10(-4) (4.0 mm) and P = 1.56 × 10(-4) (6.0 mm) but greater total posterior HOAs than FLAK P = 0.001 (4.0 mm) and P = 0.007 (6.0 mm) and PKP at 4.0-mm optical zone (P = 0.047). FLAK had fewer total anterior and posterior HOAs than PKP, but differences were not statistically significant. DSAEK grafts exhibited statistically significantly greater posterior HOAs than either type of PKP. The magnitude of anterior and posterior HOAs weakly correlated with BSCVA.
DSAEK induces fewer anterior surface HOAs but greater posterior surface HOAs than FLAK or PKP. Differences between FLAK and PKP are not statistically significant. Anterior and posterior HOAs correlate weakly with poorer visual outcome and likely contribute to decreased BSCVA after keratoplasty.
Corneal collagen cross-linking (CXL) by the use of riboflavin and ultraviolet-A light (UVA) is a promising and novel treatment for keratoconus and other ectatic disorders. Since CXL results in ...enhanced corneal stiffness, this study tested the hypothesis that CXL-induced stiffening would be proportional to the collagen autofluorescence intensity measured with nonlinear optical (NLO) microscopy.
Rabbit eyes (n = 50) were separated into five groups including: (1) epithelium intact; (2) epithelium removed; (3) epithelium removed and soaked in riboflavin, (4) epithelium removed and soaked in riboflavin, with 15 minutes of UVA exposure; and (5) epithelium removed and soaked in riboflavin, with 30 minutes of UVA exposure. Corneal stiffness was quantified by measuring the force required to displace the cornea 500 μm. Corneas were then fixed in paraformaldehyde and sectioned, and the collagen autofluorescence over the 400- to 450-nm spectrum was recorded.
There was no significant difference in corneal stiffness among the three control groups. Corneal stiffness was significantly and dose dependently increased after UVA (P < 0.0005). Autofluorescence was detected only within the anterior stroma of the UVA-treated groups, with no significant difference in the depth of autofluorescence between different UVA exposure levels. The signal intensity was also significantly increased with longer UVA exposure (P < 0.001). Comparing corneal stiffness with autofluorescence intensity revealed a significant correlation between these values (R(2) = 0.654; P < 0.0001).
The results of this study indicate a significant correlation between corneal stiffening and the intensity of collagen autofluorescence after CXL. This finding suggests that the efficacy of CXL in patients could be monitored by assessing collagen autofluorescence.
To report the results of penetrating keratoplasty (PK) in active Acanthamoeba keratitis (AK).
Nine patients with deep stromal infiltrates because of AK were treated with intensive antiamoebic medical ...therapy followed by PK during the acute infectious phase because of poor clinical response or poor compliance. Antiamoebic therapy was tapered after PK.
Visual acuity ranged from 20/15 to 20/50 after an average of 17 months after PK with no signs of recurrences. Patients had rapid resolution of symptoms.
PK is a viable option for active AK not responding to maximum medical treatment.
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