Phakic anterior chamber intraocular lens (Verisyse) implantation in children for treatment of severe ansiometropia myopia and amblyopia: Six-month pilot clincial trial and review of literature

Refractive Surgery in Myopic Children

In this paper, we summarize the current knowledge on refractive surgery performed in the myopic pediatric population. We describe the main concerns about refractive surgery in myopic children and the indications for refractive surgery in this age group. We present a range of surgical procedures that are being used for the management of unilateral/bilateral myopia in children: corneal refractive surgery (PRK, LASEK, LASIK, FS-LASIK and SMILE) and intraocular refractive surgery (phakic intraocular lens implantation, refractive lens exchange or clear lens extraction), with both their advantages and drawbacks. We also describe the various complications and measures to prevent them.

Myopia: Mechanisms and Strategies to Slow Down Its Progression

This topical review aimed to update and clarify the behavioral, pharmacological, surgical, and optical strategies that are currently available to prevent and reduce myopia progression. Myopia is the commonest ocular abnormality; reinstated interest is associated with high and increasing prevalence, especially but not, in the Asian population and progressive nature in children. The growing global prevalence seems to be associated with both genetic and environmental factors such as spending more time indoor and using digital devices, particularly during the coronavirus disease 2019 pandemic. Various options have been assessed to prevent or reduce myopia progression in children. In this review, we assess the effects of several types of measures, including spending more time outdoor, optical interventions such as the bifocal/progressive spectacle lenses, soft bifocal/multifocal/extended depth of focus/orthokeratology contact lenses, refractive surgery, and pharmacological treatments. All these options for controlling myopia progression in children have various degrees of efficacy. Atropine, orthokeratology/peripheral defocus contact and spectacle lenses, bifocal or progressive addition spectacles, and increased outdoor activities have been associated with the highest, moderate, and lower efficacies, respectively.

V4B implantable collamer lens versus Intacs corneal rings to manage anisometropic myopic amblyopia in children

OBJECTIVE

To compare the safety and efficacy of phakic intraocular lens (PIOL) versus intrastromal corneal ring segments (Intacs), for correcting high myopic anisometropia in amblyopic children.

DESIGN

Nonrandomized prospective multi-center study.

PARTICIPANTS

Thirty children, aged between 4 and 12 years, with unilateral high myopic anisometropic amblyopia were included in this study.

METHODS

Patients who were prospectively subdivided into group A, with mean preoperative manifest refraction spherical equivalent (MRSE) of -12.96 ± 4.17 D, underwent unilateral phakic posterior chamber intraocular lens implantation. Patients with mean preoperative MRSE of -8.60 ± 1.16 D in group B were treated by Intacs corneal rings. Pre- and postoperative visual acuity, ocular examination, stereoacuity, axial biometry measurements, cycloplegic refraction, and endothelial cell counts were performed in all patients.

RESULTS

Group A revealed prevention of amblyopia with improvement in spectacle-corrected distance visual acuity, where 4-6 lines were achieved in 77% of children, 2-3 lines in 4%, and just 0-1 lines restricted to 19% of children. Improvement in stereoacuity was noted in 93.33% of group A cases, whereas group B showed fewer cases of successfully improved vision, with 4-6 lines in 70% of children, 2-3 lines in 3%, and just 0-1 lines restricted to 27% of children. Improvement in stereoacuity was noted in 86.66% of cases. Two cases of cataract and 1 case of glaucoma with 1 case of uveitis were noted in the implantable contact lens (ICL) group.

CONCLUSIONS

Posterior chamber PIOLs or Intacs may provide a safe alternative in treating anisometropic myopic patients. Intacs implantation is safer with fewer complications than ICL. However, ICL implantation is advantageous over the corneal ring segment procedure owing to the wide range of errors to correct.

Management of pseudophakic myopic anisometropic amblyopia with piggyback Visian® implantable collamer lens

PURPOSE

To assess the outcomes of sulcus implantation of the Visian^® implantable collamer lens (ICL) to correct pseudophakic myopic anisometropic amblyopia with myopic shift and/or primary refractive overcorrection.

METHODS

Prospective case series enrolled 14 pseudophakic eyes of 14 patients, 5-9 years old, with history of cataract surgery and primary in the bag-intraocular lenses (IOL) implantation, followed by myopic shift and/or refractive overcorrection and anisometropic amblyopia of variable degrees. All cases had implantation of a piggyback ICL/toric ICL, to correct the myopia/myopic astigmatism. Preoperatively, we evaluated the uncorrected distance visual acuity (UCVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), intraocular pressure (IOP) and endothelial cell density (ECD). We assessed the position and vaulting of the ICLs on slit lamp examination and confirmed by Scheimpflug tomography. Postoperative follow-up was at 1st week and 1, 3, 6, 9, 12, 18 and 24 months.

RESULTS

Uncorrected distance visual acuity improved in all cases, and CDVA improved in 11 amblyopic eyes (2-4 lines). There was no evidence of interlenticular opacification (ILO) throughout the 2-year follow-up. Two cases were complicated with early postoperative acute elevation of IOP and were controlled with topical beta-blockers. Postoperative acute anterior uveitis occurred in six eyes and controlled by topical steroids. Implantable collamer lens (ICL) vault was measured using Pentacam, with mean value of 470 ± 238 μm.

CONCLUSION

Sulcus implantation of the secondary piggyback ICL to correct unilateral pseudophakic myopic refractive error in children was safe, efficient, predictable and well tolerated in management of anisometropic amblyopia in all eyes.

Phakic posterior chamber intraocular lens for unilateral high myopic amblyopia in Chinese pediatric patients

AIM

To assess the outcomes of posterior chamber implantable collamer lens (ICL) implantation in Chinese pediatric patients with unilateral high myopic amblyopia.

METHODS

Eleven eyes of 11 amblyopic patients aged 11.02±3.34y underwent ICL (model V4, Staar Surgical Inc.) implantation to treat unilateral anisometropia were studied. Visual acuity, cycloplegic refraction, contrast sensitivity, stereopsis, intraocular pressure (IOP), vaulting, corneal endothelial cell count and complications were evaluated. Patients completed follow-up at 3d, 1, 3mo and the last follow-up time (mean 8.18±2.82mo) after surgery.

RESULTS

The mean myopic anisometropia was -13.70±3.25 D preoperatively and +0.69±2.63 D at 8mo postoperatively. The logMAR corrected distance visual acuity (CDVA) of the amblyopic eye was 1.51±0.72 preoperatively and 0.75±0.40 at 8mo postoperatively. The logMAR CDVA at 3d, 1, 3 and 8mo postoperatively improved by a mean of 0.64, 1.55, 1.82 and 2.64 lines and gained more than 2 lines accounted for 18%, 45%, 45%, 64%, respectively. The contrast sensitivity of 0.5, 1 and 2 cpd in amblyopic eyes was significantly increased after surgery. No patient had near stereopsis recovery. The vaulting at 3 and 8mo was significantly lower than that at 1mo postoperatively. No other intraoperative or postoperative complications were observed, except an acute pupillary block glaucoma happened in a patient at two weeks postoperatively.

CONCLUSION

This short-term results indicate that ICL implantation can be a promising alternative therapy for high myopic anisometropic amblyopia in pediatric patients who have failed with conventional treatments and not suitable to corneal refraction surgery.

Phakic Intraocular Lenses and their Special Indications

Phakic intraocular lenses revolutionize refractive surgery and continue to serve as an excellent option for vision correction in patients who are not ideal candidates for laser vision correction. This article will review special indications of phakic intraocular lenses in the clinical practice.

Influences of topical cyclopentolate on anterior chamber parameters with a dual-Scheimpflug analyzer in healthy children

PURPOSE

To evaluate the changes of anterior segment parameters following the topical instillation of cyclopentolate hydrochloride 1% with the Galilei dual-Scheimpflug analyzer (GSA) (Ziemer Ophthalmology Co., Port, Switzerland) in healthy children.

METHODS

Fifty children (29 boys, 21 girls) were evaluated before and 60 minutes after instillation of three drops of 1% cyclopentolate hydrochloride using the GSA. The measurements before and after cycloplegia, including anterior chamber depth (ACD), anterior chamber angle (ACA), anterior chamber volume (ACV), central corneal thickness (CCT), and pupil size, were evaluated using the paired t test.

RESULTS

The mean age of the patients was 10.27 ± 3.32 years (range: 5 to 15 years). Measurements between the two sessions were significantly different for all parameters (P < .05), except for CCT (P > .05).

CONCLUSIONS

The GSA demonstrated a statistically significant increase in ACD, ACV, ACA, and pupil size following the topical application of cyclopentolate hydrochloride 1%. These results should be considered during biometric measurement and refractive surgery planning.

Acute hydrops with secondary bacterial keratitis: sequelae of paediatric refractive surgery

A 24-year-old male patient with bilateral high myopia presented to our outpatient department with sudden onset of pain and diminution of vision in his right eye. He had sequentially undergone bilateral trabeculectomy and photorefractive keratectomy at the age of 6 years in both eyes. This was followed by radial keratotomy in right eye at the age of 8 years. The slit lamp examination demonstrated the presence of infiltrates in central cornea with an underlying fluid cleft, along with 14 radial keratotomy scars. Anterior segment optical coherence tomography confirmed the presence of intrastromal cleft in communication with anterior chamber. Bacterial culture revealed coagulase-negative Staphylococcus. The patient was successfully treated with fortified antibiotics in conjunction with the sensitivity report. This case underlines the need for a cautious approach towards refractive surgery in paediatric age group and highlights the long-term sequelae of retreatments in these cases.

Posterior chamber toric phakic IOL implantation for the management of pediatric anisometropic amblyopia

PURPOSE

To report the outcomes of toric posterior chamber phakic intraocular lens (PIOL) implantation in children for the treatment of amblyopia due to anisometropia with astigmatism.

METHODS

Six eyes of 6 amblyopic patients aged 5 to 15 years underwent toric PIOL (Visian Toric ICL; STAAR Surgical Company, Monrovia, CA) implantation for refractory anisometropic amblyopia. Preoperative and postoperative clinical evaluation included slit-lamp microscopy, visual acuity, anterior/posterior segment examination, and cycloplegic refraction.

RESULTS

After a mean follow-up of 23 months (range: 15 to 34 months), mean spherical equivalent cycloplegic refraction improved from -10.21 ± 4.62 diopters (D) (range -7.5 to -19.5 D) preoperatively to -0.42 ± 0.39 D (range: -0.625 to +0.125 D) postoperatively. Corrected distance visual acuity ranged from 20/40 to 20/200 preoperatively and 20/20 to 20/60 postoperatively. Five of the 6 eyes gained more than 3 lines of corrected distance visual acuity with a maximum gain of 8 lines in one eye. One eye showed an improvement of more than 2 lines (change in preoperative visual acuity of 20/100 to 20/60 postoperatively). No patients lost any lines of visual acuity. All eyes remained quiet. All PIOLs remained well centered throughout the follow-up period.

CONCLUSION

Toric PIOL implantation may be a viable therapeutic modality in children with clinically significant anisometropic ametropia and astigmatism with secondary amblyopia who have been refractory to medical treatment including spectacles or contact lenses. Longer follow-up visits with larger sample populations will evaluate more effectively the long-term efficacy and late-onset of complications.

Foldable iris-fixated intraocular lens implantation in children

PURPOSE

  To describe the results of foldable iris-fixated intraocular lens (IOL) implantation in children.

METHODS

  Children with high bilateral or unilateral myopia who were intolerant of spectacle or contact lens correction were implanted with an iris-fixated foldable IOL and prospectively followed. We measured pre- and postoperative visual acuity, refraction, endothelial cell density (ECD) and National Eye Institute Visual Functioning Questionnaire-25.

RESULTS

  Eleven eyes of six children were implanted. Indications were high bilateral myopia in children with comorbid neurobehavioural disorders, high anisometropia and high myopic astigmatism. Mean preoperative spherical equivalent (SE) refraction was -14.6 dioptres (D)±4.2 SD. Mean follow-up was 15 months. Postoperative SE refraction was -2.40 D±2.40 SD. Corrected distance visual acuity (CDVA) improved from mean logMAR 0.84±0.4 SD to postoperative 0.67±0.34 SD (p=0.005). CDVA was reduced because of coexistent ocular disorders and amblyopia. Vision-related quality of life (QOL) measures improved significantly. There were no intraoperative or postoperative serious complications.

CONCLUSION

  Foldable iris-fixated IOL insertion can give a significant improvement in vision and in vision-related QOL in a subset of paediatric patients with special refractive needs who are intolerant to conventional treatment. Long-term follow-up is required for monitoring of ECD.

Pediatric refractive surgery: corneal and intraocular techniques and beyond

Refractive surgery has now been used successfully to treat severe anisometropia and isoametropia associated with amblyopia in children who cannot wear standard spectacles or contact lenses. Extraocular techniques include photorefractive keratectomy, laser-assisted subepithelial keratomileusis, and laser-assisted in situ keratomileusis. Intraocular techniques include refractive lensectomy and phakic intraocular lenses and are still being investigated in children for refractive errors outside the treatment dose capabilities of the excimer laser. This workshop discusses the various techniques, how and when to use each, and their risks and benefits. Newer techniques currently being used in adults that may someday be used in children are also introduced.

Influences of cyclopentolate hydrochloride on anterior segment parameters with Pentacam in children

PURPOSE

To investigate the effects of cyclopentolate hydrochloride 1% on the main numerical parameters of anterior segment with Pentacam rotating Scheimpflug camera in children.

SETTING

Ege University Faculty of Medicine, Department of Ophthalmology.

METHODS

Pentacam measurements of 50 (23 boys and 27 girls) children before and after 45 min of cyclopentolate hydrochloride 1% instillation were performed and compared with 31 (17 boys and 14 girls) no medication instilled control group. Measurements of the control group (cycloplegia-free) were taken at two separate sessions with 45-min intervals. For comparison of the test parameters, paired t-test in the groups and unpaired t-test in between the groups were used.

RESULTS

Mean ages in the study and control groups were 10.06 ± 2.87 (range 6 and 16 years) and 9.87 ± 2.72 (range 6 and 16 years), respectively, and the difference was statistically insignificant (p > 0.05). In the study group, measurements between two sessions were significantly different for the parameters of anterior chamber depth (ACD), anterior chamber volume (ACV) and central corneal thickness (CCT) (p < 0.05), whereas none of the parameters was different between two sessions for control group.

CONCLUSIONS

Cyclopentolate hydrochloride 1% instillation leads to significant decrement in CCT. ACD and ACV are the other important refractive parameters that increase significantly after cycloplegia. Effects of cycloplegia on these parameters for Pentacam measurements should be regarded for proper clinical interpretation in children.

Pediatric phakic intraocular lens surgery: review of clinical studies

PURPOSE OF REVIEW

To report on the accumulating peer-reviewed data of phakic intraocular lens (pIOL) implantation in the pediatric population. I evaluate and compare the published peer-reviewed articles for the reported efficacy and complications of phakic intraocular lens implantations in children for correction of clinically significant high refractive errors.

RECENT FINDINGS

Multiple studies have shown the relevancy and effectiveness of pIOL implantation as an alternative surgical management for highly significant pediatric ametropia in selective patients who are noncompliant with medical treatment.

SUMMARY

In the management of clinically significant severe pediatric ametropic and/or anisometropic myopia or hyperopia and in the event of nonadherence to traditional medical treatment, phakic anterior chamber IOL implantation is currently considered an effective modality of treatment. Long-term follow-up of pediatric patients following pIOL implantation is necessary. Future clinical trials should focus on children of various age groups to assess the variables of visual acuity gain or loss, stereopsis, contrast sensitivity, high-order aberrations, corneal physiology, and long-term complications to accurately and properly address the safety and efficacy of the type of and the best time for pIOL implantation in treatment and/or prevention of amblyopia in children.

Refractive surgery in children

PURPOSE OF REVIEW

To evaluate recent literature regarding indications and outcomes for refractive surgery in children, including laser in-situ keratomileusis, laser epithelial keratomileusis, photorefractive keratectomy, and refractive intraocular lens placement.

RECENT FINDINGS

Refractive surgery in children is controversial. Recent publications have reported refractive surgery to treat strabismus and both ametropic and anisometropic amblyopia. Questions remain as to the age at which to perform the surgery, and which specific procedure to perform. Choice of technique depends on the clinical situation.

SUMMARY

Refractive surgery is an option for children with amblyopia and strabismus who fail treatment with spectacles or contact lenses. Prospective controlled studies are needed, and longer follow-up will answer questions about the utility and safety of refractive surgery in children.