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Published on: September 20, 2024
Outcomes of the Q value-based nomogram in managing pediatric versus adult keratoconus: a prospective interventional
Mohammed Iqbal1, Abdallah Hammour2, Ahmed Elsayed2
1Department of Ophthalmology, Faculty of Medicine, Sohag University, Sohag, Egypt.
Insights
The Q value-based nomogram (Q-N) effectively treated pediatric keratoconus (KCN), showing visual and refractive improvements comparable to adults. This objective approach offers good corneal remodeling for KCN patients.
Area of Science:
- Ophthalmology
- Corneal Surgery
- Vision Science
Background:
- Keratoconus (KCN) is a progressive corneal ectatic disorder causing vision loss.
- Pediatric KCN is notably aggressive and requires effective treatment strategies.
- Current treatments aim to improve visual acuity and corneal shape.
Purpose of the Study:
- To evaluate the visual, refractive, and topographic outcomes of Keraring segment implantation using a novel Q value-based nomogram (Q-N).
- To compare the efficacy of the Q-N in treating pediatric versus adult KCN.
- To assess the safety and effectiveness of this objective nomogram-based approach.
Main Methods:
- A prospective, multicenter, non-randomized trial involving 47 eyes (33 adult, 14 pediatric).
- Femtosecond laser-assisted implantation of a single 210° arc-length Keraring segment guided by the Q-N.
- Follow-up included visual acuity, cycloplegic refraction, and corneal topography at 6 months.
Main Results:
- Both adult and pediatric groups showed significant improvements in visual acuity, refraction (sphere, SE), and Kmax post-surgery.
- Mean changes in visual, refractive, and topographic parameters were comparable between adult and pediatric KCN patients.
- No postoperative complications were reported in either group, indicating a favorable safety profile.
Conclusions:
- The objective Q-N is effective for treating pediatric keratoconus, yielding results comparable to adult KCN treatment.
- Q-N facilitates corneal remodeling, leading to improved visual, refractive, and topographic outcomes in both age groups.
- Further multicenter randomized trials with larger pediatric KCN cohorts are recommended to validate these findings.
Background:
Keratoconus (KCN) is an ectatic disorder of the cornea characterized by stromal weakness and apical protrusion of the cornea, and is associated with a gradual and painless reduction in visual acuity. KCN in pediatric patients has certain important characteristics, such as a progressive and aggressive nature. We aimed to analyze the visual, refractive, and topographic outcomes of implanting a single 210° arc-length Keraring segment according to a novel, objective, Q value-based nomogram (Q-N) for the treatment of pediatric versus adult KCN.
Methods:
This prospective, multicenter, non-randomized, open-label trial included 47 eyes of 47 patients who were allocated to one of two groups. The adult group included 33 eyes of patients ≥ 18 years of age, whereas the pediatric group included 14 eyes of patients aged 14 - 17 years. All patients underwent femtosecond laser-assisted implantation of a single 210° arc-length Keraring segment according to the Q-N and were followed up for 6 months. All eyes underwent visual acuity measurement, cycloplegic refraction, and corneal topography at baseline and 6 months after surgery.
Results:
The study groups were comparable in terms of sex proportions and KCN grades (both P > 0.05). The adult group exhibited significant postoperative improvements in mean uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), sphere, cylinder, spherical equivalent (SE), and Kmax (all P < 0.001) with a mean change of -0.56 logarithm of the minimal angle of resolution (logMAR), - 0.40 logMAR, 3.07 diopters (D), 0.70 D, 3.42 D, and - 5.26 D, respectively. The pediatric group exhibited significant postoperative improvements in mean UDVA, CDVA, sphere, SE, and Kmax (all P < 0.05) with a mean change of - 0.62 logMAR, - 0.34 logMAR, 3.18 D, 3.67 D, and - 5.37 D, respectively. There were no significant differences between the groups in terms of the mean change in visual, refractive, and topographic variables (all P > 0.05). No postoperative complications were observed in either group.
Conclusions:
Use of the objective Q-N was efficient in the treatment of pediatric KCN, with postoperative improvements in the mean visual, refractive, and topographic parameters, comparable to outcomes in adult keratoconus. Q-N achieved good corneal remodeling with subsequent improvements in visual, refractive, and topographic outcomes in both adult and pediatric patients with keratoconus. To verify our preliminary findings, we recommend further multicenter randomized clinical trials using the Q-N nomogram in a larger sample of pediatric patients with KCN as an adjunct treatment before or after CXL.
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