Photorefractive keratectomy in children

Posterior scleral reinforcement surgery effectively slows the rate of high myopic progression in children

PURPOSE

To investigate the rate of axial length elongation and high myopia progression in operated eyes before and after posterior scleral reinforcement (PSR) surgery.

METHODS

This was a retrospective study. Children with pathological myopia treated with PSR at Beijing Tongren Hospital between May 2013 and May 2020 were recruited into the PSR surgery group. Children matched for age and myopia were recruited into the control group. All children underwent comprehensive ophthalmologic examinations. The presurgical and postsurgical rates of axial length elongation and myopic (spherical equivalent) progression were calculated.

RESULTS

A total of 35 PSR patients were included in the study. The mean age was 6.5±3.0 years (range 2 to 14 years). Mean follow-up was 544 days (range 216 to 1657 days). The rate of axial length elongation was significantly less after posterior scleral reinforcement surgery (0.505±0.048mm per year prior to surgery; 0.382±0.045mm per year after surgery, P<0.001). The rate of myopic progression decreased after posterior scleral reinforcement surgery (1.162±0.118 D per year prior to surgery; 0.153±0.437 D per year after surgery, P=0.0239). There was no statistically significant difference in axial length elongation or myopic progression between pre-inclusion and post-inclusion in the control group. Moreover, the children's best-corrected visual acuity was significantly improved after posterior scleral reinforcement surgery (P<0.001).

CONCLUSION

Posterior scleral reinforcement surgery effectively decreased the rate of high myopic progression and axial length elongation in children.

IMI-Management and Investigation of High Myopia in Infants and Young Children

Purpose

The purpose of this study was to evaluate the epidemiology, etiology, clinical assessment, investigation, management, and visual consequences of high myopia (≤-6 diopters [D]) in infants and young children.

Findings

High myopia is rare in pre-school children with a prevalence less than 1%. The etiology of myopia in such children is different than in older children, with a high rate of secondary myopia associated with prematurity or genetic causes. The priority following the diagnosis of high myopia in childhood is to determine whether there is an associated medical diagnosis that may be of greater overall importance to the health of the child through a clinical evaluation that targets the commonest features associated with syndromic forms of myopia. Biometric evaluation (including axial length and corneal curvature) is important to distinguishing axial myopia from refractive myopia associated with abnormal development of the anterior segment. Additional investigation includes ocular imaging, electrophysiological tests, genetic testing, and involvement of pediatricians and clinical geneticists is often warranted. Following investigation, optical correction is essential, but this may be more challenging and complex than in older children. Application of myopia control interventions in this group of children requires a case-by-case approach due to the lack of evidence of efficacy and clinical heterogeneity of high myopia in young children.

Conclusions

High myopia in infants and young children is a rare condition with a different pattern of etiology to that seen in older children. The clinical management of such children, in terms of investigation, optical correction, and use of myopia control treatments, is a complex and often multidisciplinary process.

[TransPRK in general anesthesia-An alternative for anxious patients]

OBJECTIVE

The aim was to analyze and compare the refractive results of anxious patients treated with transepithelial photorefractive keratectomy (TransPRK) while under general anesthesia (ITN) versus patients treated under local anesthesia (TRO).

MATERIAL AND METHODS

The TransPRK treatment was performed with the AMARIS 1050 RS laser (SCHWIND eye-tech-solutions GmbH, Kleinostheim, Germany) in a group of patients with ITN and a group of patients, treated as usual with TRO. The method used an aspheric aberration neutral ablation profile, as well as SmartPulse technology and 7D eyetracking. In ITN propofol and rocuronium were injected intravenously. The artificial respiration was via a resuscitation bag after intubation with a laryngeal mask. To achieve pain insensitivity in the group of patients in TRO three drops of Conjucain Edo 0.4% were instilled at intervals of a few minutes. Follow-up examinations were performed after 1 and 4 days and after 1 and 3 months.

RESULTS

A total of 35 consecutive TransPRK laser treatments under ITN were retrospectively compared with a group of 699 eyes treated with TransPRK under TRO in the period from February 2017 to December 2021. The preoperative sphere had a range of -5.50 to -1.0 dpt, the average cylinder was 1.19 dpt and cylinders were treated up to 4.75 dpt. The results after 3 months follow-up showed a predictability of 100% eyes within the target correction of less than 0.5 dpt in ITN and in TRO 97%. The astigmatic correction showed 91% of eyes in ITN with less than 0.5 dpt and an angle of error of 83% within ±5°. In TRO 96% of eyes showed astigmatic correction with less than 0.5 dpt and an angle of error of 77% within ±5°. After 3 months 83% of eyes treated in ITN reached a visual acuity of 1.0 or more and 84% of eyes treated in TRO.

CONCLUSION

The TransPRK performed in ITN led to equal refractive results than when treated as usual in TRO. For anxious patients there is the possibility of laser vision correction in ITN. Because of shorter treatment time and accordingly shorter time under general anesthesia, TransPRK is an advantage for LASIK surgery.

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.

Visual outcomes of photorefractive keratectomy in non-children with anisometropic amblyopia: One-year Follow-up Outcomes

OBJECTIVE

To evaluate the safety, efficiency, short term stability, and sensory results of photorefractive keratectomy (PRK) in anisometropic in non-compliant children with correction.

METHODS

Twelve eyes of 12 children with an age range: 6-17 years and anisometropic amblyopia who underwent PRK under general anesthesia to correct the dioptric difference between the eyes were included in this study. A complete ophthalmic assessment including refractive status, uncorrected and corrected distance visual acuity (UDVA & CDVA), and binocular vision status using the Worth 4-dot test and stereopsis were performed before and 1, 3, 6, and 12 months after PRK.

RESULTS

The mean preoperative CDVA was 0.34 ± 0.24 LogMAR which showed a statistically significant improvement at 12 months (0.20 ± 0.19, p = 0.024) after surgery compared to the preoperative assessment. (p = 0.003) The mean preoperative UDVA was 0.63 ± 0.24 LogMAR that increased to 0.44 ± 0.24, 0.32 ± 0.16, 0.25 ± 0.19, and 0.25 ± 0.19 LogMAR at 1, 3, 6, and 12 months after PRK, respectively. One to three lines improvement in UDVA and CDVA was seen in 10 (83.4%) and 8 eyes (66.7%); while one line UDVA and CDVA loss was seen in one (8.3%) and one (8.3%) eye and unchanged UDVA and CDVA was seen in 1 (8.3%) and 3 eyes (25%), respectively. The mean preoperative stereoacuity was 341.9 ± 245.7 s of arc, which significantly improved to 166.6 ± 87.5 s of arc 12 months after PRK. (p = 0.012).

CONCLUSION

PRK was an effective surgical alternative to improve visual acuity and stereopsis in anisometropic children who did not cooperate with conventional methods of amblyopia therapy.

Small Incision Lenticule Extraction for Correction of Pediatric Unilateral Anisometropic Myopia

PURPOSE

To evaluate the effects of femtosecond laser small incision lenticule extraction (SMILE) on treating unilateral myopic anisometropia in children with spectacles or contact lens intolerance.

METHODS

This was a retrospective study that included children with unilateral myopic anisometropic amblyopia who underwent a SMILE procedure at Alpha Vision Center, Zagazig, Egypt, from January 2014 to December 2016.

RESULTS

One hundred twenty-four eyes of 124 patients were included in this study. The postoperative corrected distance visual acuity (CDVA) at the 3-month and 1-, 2-, 3-, and 4-year follow-up visits improved significantly (P < .05) compared to the preoperative CDVA, indicating the safety of the procedure. At the 3-month postoperative visit, 23% of cases showed improvement of one or more lines of CDVA, whereas only 2% of cases showed a decline of only one line. Moreover, the postoperative uncorrected distance visual acuity compared favorably to the preoperative CDVA, denoting the efficacy of the refractive correction. The spherical equivalent was within ±0.50 diopters of the intended correction in 75% of the cases and within ±1.00 diopters in 89% of the cases. The intraoperative complications were scarce and relatively innocuous.

CONCLUSIONS

SMILE is a safe and effective alternative method for correcting myopic anisometropic amblyopia in children with spectacles or contact lens intolerance with good refractive results. A larger study with longer follow-up periods is necessary to determine the long-term effects of SMILE. [J Refract Surg. 2021;37(8):510-515.].

Femtosecond Laser-Assisted LASIK in Children With Hyperopia and Anisometropic Amblyopia: 7 Years of Follow-up

PURPOSE

To analyze clinical and functional results of femtosecond laser-assisted laser in situ keratomileusis (FSLASIK) in children with hyperopia and unilateral anisome-tropic amblyopia.

METHODS

The study included 24 patients (24 eyes) aged 5 to 15 years. Before the surgery, the mean manifest refractive spherical equivalent (MRSE) of amblyopic eyes was +3.90 ± 1.60 diopters (D) (range: +1.50 to +6.80 D) and the mean refractive anisometropia was 3.06 ± 1.64 D (range: 0.87 to 7.50 D). Every patient had at least 1 year of ineffective traditional amblyopia treatment before surgery. The mean follow-up period was 7 years (range: 6.9 to 7.4 years).

RESULTS

At the final follow-up visit, the mean MRSE of operated eyes was +0.41 ± 1.35 D (range: -1.13 to +3.88 D) (P < .001) and anisometropia in MRSE notation was 1.39 ± 1.15 D (range: 0.00 to 4.63 D). Postoperative spherical equivalent was within ±0.50, ±1.00, and ±2.00 D in 31%, 38%, and 92%, respectively. There were no complications. All patients showed a one to seven line gain of corrected distance visual acuity.

CONCLUSIONS

FS-LASIK was an effective method of hyperopia correction in this cohort of children with amblyopia, resulting in reduction in anisometropia, restoration of refractive balance, and functional improvement in the amblyopic eye when traditional methods failed. [J Refract Surg. 2020;36(6):366-373.].

Long-term Effects After Pediatric LASIK for Anisometropic Amblyopia in Two Patients

PURPOSE

To report long-term follow-up of two pediatric patients who underwent laser in situ keratomileusis (LASIK) for myopic anisometropic amblyopia.

METHODS

Case series.

RESULTS

Two patients who underwent unilateral LASIK in 1999 for anisometropic amblyopia were clinically assessed 16 years after their initial procedure with visual acuity testing, refraction, stereopsis, axial length, corneal topography, slit-lamp examination, and quality of life assessment. Patients had stable corrected distance visual acuity, balanced refraction, improved stereopsis, and good visual quality of life. Corneal topography showed a mildly decentered ablation bed with no evidence of ectasia.

CONCLUSIONS

LASIK in the pediatric population requires special considerations, including fixation and centration issues, microkeratome selection, and refractive endpoint. The two patients were found to have stable corneal topography, visual acuity, and stereopsis 16 years after initial treatment. [J Refract Surg. 2019;35(6):391-396.].

Photorefractive Keratectomy for Myopic Anisometropia: A Retrospective Study on 18 Children

Purpose

To evaluate the safety and efficacy of photorefractive keratectomy (PRK) performed under topical anesthesia in children with myopic anisometropia.

Methods

Medium to high unilateral myopia was corrected in 18 patients by PRK. At the time of surgery patients were between 7 and 17 years of age (mean 10 years). All the surgical procedures were performed under topical anesthesia. Pre- and postoperative data regarding visual acuity, eye alignment, and binocular vision were analyzed.

Results

The mean correction (SE) obtained with excimer laser was −8.21 D (range: −2.25 to −14.50, SD 3.90). The mean preoperative best spectacle-corrected visual acuity (BSCVA) was 20/70, and the postoperative mean BSCVA was 20/50. A significant difference was observed between the arithmetic mean of the preoperative and postoperative BSCVA (p=0.001). Two of 18 patients improved stereopsis; furthermore, surgery variation strabismus was registered in 33.3% of the patients, following PRK. Patients were followed up for a mean of 39 months.

Conclusions

The treatment of medium to high unilateral myopia with PRK under local anesthesia was found effective and safe in pediatric and adolescent patients. This procedure may improve ocular alignment and stereopsis. Further studies are needed to increase the patient experience and extend follow-up time in order to assess the long-term stability of the results.

Femtosecond laser corneal refractive surgery for the correction of high myopic anisometropic amblyopia in juveniles

AIM

To evaluate the effects of femtosecond laser-assisted in situ keratomileusis (FS-LASIK) and small-incision lenticule extraction (SMILE) to correct high myopic anisometropic amblyopia in juvenile patients.

METHODS

From November 2013 to January 2015, 33 amblyopic patients with high myopic anisometropic amblyopia were studied. FS-LASIK (30 eyes) or SMILE (3 eyes) was performed in the amblyopic eyes. Visual acuity, refraction, contrast sensitivity, stereoacuity and complications were evaluated. Patients completed follow-up examinations at 3d, 1mo, 3mo and the last follow-up time (mean 8.17±3.23mo) after surgery.

RESULTS

The mean age at surgery was 9.04±3.04y (range 6-16y). The mean spherical equivalent in the amblyopic eyes was significantly decreased from -10.00±2.39 D preoperatively to -0.06±1.06 D at 1mo, -0.19±1.33 D at 3mo and -0.60±1.43 D at approximately 8mo postoperatively (P<0.05 for all). The mean myopic anisometropia was significantly decreased from -9.45±2.33 D preoperatively to +0.37±1.48 D at 1mo, -0.46±1.47 D at 3mo and -0.09±1.83 D at approximately 8mo (P<0.05 for all). The logarithm of the minimum angle of resolution (logMAR) for uncorrected and corrected distance visual acuity (UDVA and CDVA, respectively) of the amblyopic eye improved from 1.74±0.35 and 0.98±0.63 preoperatively to 0.45±0.31 and 0.41±0.33 at approximately 8mo after surgery, respectively. The logMAR CDVA at 3d, 1, 3 and 8mo postoperatively improved by means of 1.42, 2.22, 2.96, and 4.39 lines, and a gain of more than two lines accounted for 45%, 50%, 74% and 86% of all patients, respectively. The contrast sensitivity of both amblyopic eyes and dominant eyes at 0.5, 2, 8 cycles per degree was significantly improved postoperatively (P<0.05 for all). Of the 33 pediatric patients, no patients had near stereopsis preoperatively and seven patients (21.2%) recovered near stereopsis (400″ to 60″) at approximately 8mo after surgery. No intraoperative or postoperative complications occurred in any patient.

CONCLUSION

FS-LASIK or SMILE can be promising alternative methods to correct high myopic anisometropic amblyopia in juvenile patients who have failed with traditional approaches.

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.

Refractive Surgery in Children

Refractive surgery in children is controversial. The main indications are bilateral high ametropia and anisometropia where conventional treatment with spectacles or contact lens is not tolerated. Other reported indications include accommodative strabismus and previous cataract surgery. The most commonly performed procedures currently are surface ablation procedures using excimer laser. The main disadvantage of surface ablation procedures is refractive regression, which is more pronounced in higher degrees of ametropia. More recently, there is a growing number of studies evaluating the safety and effectiveness of phakic intraocular lenses (IOLs) as an alternative surgical management for children who are noncompliant with conventional treatment and unsuitable for laser ablative procedures. The advantages of phakic IOLs are reversibility, predictability, and lack of regression. The principal concern with phakic IOL insertion is long-term endothelial cell loss. Clear lens extraction has been performed in patients with shallow anterior chambers beyond the range of corneal laser refractive procedures; however, major drawbacks include loss of accommodation and significant risk of retinal detachment. In summary, results to date show that refractive surgery can be successfully performed in children and meets an important need in a select subgroup of patients who are recalcitrant to traditional therapy. Issues that remain controversial are the age at which to perform surgery, choice of procedure, need for anesthesia, instability of refractive errors in children, and long-term safety considerations.

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.

Pediatric refractive surgery in evolution

With the advent of corneal refractive surgery using excimer laser technology, treatment for corneal and refractive disorders have advanced tremendously and become very precise and predictable. The use of these techniques in the treatment of corneal and refractive disorders in children, especially during the amblyogenic ages, would be invaluable. Numerous reports on refractive surgery in children have demonstrated that it can be performed safely and efficaciously in the pediatric population. However, controversy still exists whether it should be done in this population. We explore the available published data to address this controversy.

Photorefractive keratectomy in treatment of refractive amblyopia in the adult population

PURPOSE

To evaluate changes in corrected distance visual acuity (CDVA) after photorefractive keratectomy (PRK) in amblyopic cases.

SETTING

Ankara Ataturk Training and Research Hospital 1st Ophthalmology Clinic, Ankara, Turkey.

DESIGN

Retrospective case series.

METHODS

The medical records of cases of anisometropic amblyopia treated by excimer laser PRK were reviewed. Inclusion criteria were no previous refractive correction, occlusion treatment, or chemical penalization before age 15 years. Anisometropic amblyopia was defined as a more than 2-line difference in CDVA and a refractive error difference greater than 3.00 diopters (D) between 2 eyes of the same patient. Final visual acuity measurements were performed at the end of the sixth postoperative month.

RESULTS

The study enrolled 16 hyperopic patients and 34 myopic patients with a mean age of 33.3 years. The mean preoperative spherical equivalent was -7.46 D ± 2.90 (SD) in myopic eyes and +4.15 ± 2.56 D in hyperopic eyes. The differences between the preoperative and postoperative uncorrected distance visual acuity and CDVA were statistically significant (P=.001). The mean CDVA was 0.47 ± 0.17 preoperatively and 0.61 ± 0.19 postoperatively. The CDVA decreased in 3 cases (6%), stayed the same in 12 cases (24%), and increased in 35 cases (70%). There was no statistically significant correlation between the severity of amblyopia and the increase in CDVA (r = 0.20, P=.165).

CONCLUSION

After PRK to eliminate and correct refractive errors in anisometropic amblyopia, visual acuity improved significantly in 70% of adult patients with no previous occlusion or chemical penalization treatment.

Laser in situ keratomileusis for the treatment of refractive accommodative esotropia

PURPOSE

To demonstrate the effectiveness of refractive surgery with an excimer laser to correct hyperopia and convergent strabismus caused by compensatory accommodation of refractive error.

DESIGN

Prospective, interventional, noncomparative case series.

PARTICIPANTS

Forty-six eyes of 23 patients with hyperopia and fully or partially refractive accommodative esotropia.

METHODS

Patients were treated with an excimer laser and the LASIK technique between 2000 and 2010.

MAIN OUTCOME MEASURES

Preoperative and postoperative refractive spherical equivalent and ocular alignment.

RESULTS

Mean age ± standard deviation [SD] was 25 ± 12.6 years. Mean hyperopia ± SD was 3.67 ± 1.28 diopters (D) before surgery and 0.21 ± 0.59 D after surgery (P<0.001). The mean angle of deviation without correction was 21.0 prism diopters (Δ) before surgery and 3.7 Δ after surgery (P<0.001).

CONCLUSIONS

Refractive surgery with excimer laser is a promising option for the treatment of refractive accommodative esotropia.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Laser-assisted subepithelial keratectomy and photorefractive keratectomy for post-penetrating keratoplasty myopia and astigmatism in adults

PURPOSE

To evaluate whether laser-assisted subepithelial keratectomy (LASEK) and photorefractive keratectomy (PRK) achieve effective targeted correction and the extent of post-treatment corneal haze after corneal transplantation.

SETTING

Nonhospital surgical facility, Calgary, Alberta, Canada.

DESIGN

Evidence-based manuscript.

METHODS

This study evaluated visual acuity, refractive error correction, and potential complications after LASEK or PRK to eliminate refractive error differences after penetrating keratoplasty in adults. A Nidek EC-5000 or Technolas 217 excimer laser was used in all treatments.

RESULTS

At last follow-up (mean 20.50 months post laser), the mean spherical equivalent (SE) decreased from -2.71 diopters (D) ± 4.17 (SD) to -0.54 ± 3.28 D in the LASEK group and from -4.87 ± 3.90 D to -1.82 ± 3.34 D in the PRK group. The mean preoperative uncorrected distance visual acuity (UDVA) was 1.63 ± 0.53 and 1.45 ± 0.64, respectively, and the mean postoperative UDVA, 0.83 ± 0.54 and 0.90 ± 0.55, respectively. The improvement in SE and UDVA was statistically significant in both groups (P < .01). The mean haze (0 to 3 scale) at the last follow-up was 0.46 ± 0.708 in the LASEK group and 0.58 ± 0.776 in the PRK group.

CONCLUSIONS

The UDVA improved and refractive errors were effectively reduced after LASEK or PRK in eyes with previous PKP. There was no significant difference in the change in SE, UDVA, or corrected distance visual acuity between LASEK and PRK. Some patients had evidence of corneal haze, although the difference between the groups was not significant.

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.

LASIK correction of vision in adults with unilateral amblyopia

PURPOSE

to evaluate the effects of laser refractive surgery in adult patients with mild to moderate amblyopia due to anisometropic myopia.

METHODS

a retrospective review of 30 patients (60 eyes) with unilateral amblyopia (corrected distance visual acuity [CDVA] 0.6 or worse) who underwent simultaneous bilateral laser vision correction using the Technolas 217z excimer laser (Bausch & Lomb) was performed. Mean patient age was 31.03 ± 10.05 years (range: 18 to 53 years). Visual outcomes in the amblyopic eye were compared with those in the fellow nonamblyopic control eye of the same patient.

RESULTS

mean preoperative CDVA improved in amblyopic eyes from 0.50 ± 0.13 to 0.57 ± 0.20 postoperatively (average gain of 0.075 ± 0.14; P=.007) and improved from 0.92 ± 0.12 preoperatively to 0.93±0.15 after surgery (mean gain of 0.013 ± 0.14; P=.603) in the fellow nonamblyopic eyes. The safety index was significantly greater in the amblyopic eyes compared with the nonamblyopic fellow eyes (1.15 ± 0.30 vs 1.02 ± 0.15, P=.035), therefore, no difference was noted in efficacy (P=.913). Five of 30 eyes with mild to moderate amblyopia gained 2 to 4 lines of CDVA.

CONCLUSIONS

laser refractive surgery for myopic correction was found to be safe and effective in eyes with mild to moderate amblyopia.

Refractive surgery in children: treatment options, outcomes, and controversies

PURPOSE

To summarize the evolution of the treatment of pediatric refractive errors, with an emphasis on recent advancements in the use of refractive surgery to treat children.

DESIGN

Literature review.

METHODS

We searched MEDLINE (1950 through October 2007), the Cochrane library (December through October 2007), and the Cumulative Index for Nursing and Allied Health Literature (December 1982 through October 2007) for English language articles using the following search strategy with MeSH terms and key words: pediatric refractive errors and amblyopia, anisometropia, hyperopia, myopia, laser in situ keratomileusis (LASIK), photorefractive keratectomy (PRK), laser epithelial keratomileusis (LASEK), excimer laser, refractive intraocular lens (IOL). We also searched the bibliographies of all identified articles.

RESULTS

No multicenter, long-term, controlled trial has been published on the use of refractive surgery in children. The current literature shows that LASIK, PRK, and LASEK show promising results in children with refractive amblyopia over the intermediate follow-up period. Corneal haze and myopic regression are the main complications, especially in very high myopia (> 12 diopters). In such patients with extremely high myopia, small studies have reported phakic IOLs or clear lens extraction with or without IOL implantation to be a useful alternative.

CONCLUSIONS

Refractive surgery is appropriate in children with severe anisometropia or bilateral high ametropia that is resistant to conventional therapy. More information is needed before pediatric refractive surgery can be widely adopted by the ophthalmic community. This could be achieved with a large, prospective, multicenter, randomized, controlled clinical trial.

Phakic intraocular lens correction of high ametropia in children with neurobehavioral disorders

PURPOSE

A subset of children with high ametropia and neurobehavioral disorders have chronic difficulties with spectacle or contact lens wear. We report the results of refractive surgery in a series of these children treated using bilateral or unilateral phakic intraocular lenses (IOLs) for ametropia >10 D.

METHODS

Clinical course and outcome data were collated prospectively in a group of 12 children (mean age, 10.1 years; range, 4-17 years) with neurobehavioral disorders exacerbated by poor compliance with spectacles. Myopia in 18 eyes ranged from -10.0 to -22.75 D (mean, -15.2 D) and in 2 hyperopic eyes from +10.25 to +10.75 (mean, +10.5 D). Goal refraction was approximately 0 to +1 D. Correction was achieved by implantation of an iris-enclaved phakic IOL under general anesthesia. Mean follow-up was 9.1 months (range, 3-15 months).

RESULTS

Myopia correction averaged 14.5 D and hyperopia correction 9.4 D. Eighty-six percent of eyes (17/20 eyes) were corrected to within +/- 1 D of emmetropia and the remaining 14% (3 eyes) to within +/- 2 D. Uncorrected visual acuity improved substantially in all 20 eyes (60-fold; from a mean of 20/3400 to a mean of 20/57). Ocular comorbidities in each child accounted for residual postoperative, subnormal visual acuity (eg, amblyopia, nystagmus, albinism, regressed retinopathy of prematurity). Visual functions (measured using a 23-item validated survey) improved. One eye required IOL exchange; no other clinically significant complications have been encountered.

CONCLUSIONS

Phakic IOL implantation improves visual function substantially in neurobehaviorally impaired children who have high ametropia and difficulties wearing glasses.

Facilitation of amblyopia management by laser in situ keratomileusis in high anisometropic hyperopic and myopic children

PURPOSE

To assess the efficacy of laser in situ keratomileusis (LASIK) in facilitating amblyopia management of children from 6 to 14 years old, with high hyperopic and myopic anisometropia.

PATIENTS AND METHODS

Between 2000 and 2005, 42 children with high hyperopic anisometropic amblyopia and 32 children with high myopic anisometropic amblyopia underwent LASIK to reduce their anisometropia. LASIK was performed under topical or general anesthesia. Pre- and postoperative best-corrected visual acuity, cycloplegic refraction, and binocular vision were recorded. Follow-up ranged from 6 months to 3 years, the averages of which were 17.45 months in the hyperopic group and 18.31 months in myopic group.

RESULTS

Hyperopic anisometropia correction ranged from +3.50 D to +7.75 D, and the mean postoperative anisometropia was +0.56 +/- 0.75 D at 3 years. Myopic anisometropia correction ranged from -15.75 to -5.00 D and the mean postoperative anisometropia at 3 years was -2.20 +/- 1.05 D. The best-corrected visual acuity for distance and reading in the myopic group improved from 0.4 +/- 0.25 and 0.58 +/- 0.27, respectively, before surgery to 0.59 +/- 0.28 and 0.96 +/- 0.35, respectively, 3 years after surgery. In the hyperopic group, best-corrected visual acuity for distance and reading improved from 0.23 +/- 0.21 and 0.34 +/- 0.32, respectively, before surgery to 0.53 +/- 0.31 and 0.80 +/- 0.33, respectively, 3 years after surgery. The proportion of patients who had stereopsis increased from 19.1% preoperatively to 46.7% postoperatively in the hyperopic group and from 19% to 89% in the myopic group.

CONCLUSIONS

LASIK reduced high hyperopic and myopic anisometropia in children, thus facilitating amblyopia management and improving their visual acuity and stereopsis.

Unilateral lens extraction for high anisometropic myopia in children and adolescents

INTRODUCTION

A subpopulation of children with anisometropic myopia, amblyopia, and neurobehavioral disorders is noncompliant with spectacle wear and ill-suited to correction using contact lenses. We report the results of refractive surgery in a series of these children treated using lensectomy alone (clear lens extraction) or lensectomy with simultaneous implantation of an intraocular lens (refractive lens exchange).

METHODS

Clinical course and outcome data were collated retrospectively in a group of 7 children and adolescents (mean age, 9.1 years; range, 4-20 years) with neurobehavioral disorders and noncompliance with spectacle wear for anisometropic myopia. Myopia in the 7 eyes ranged -11.9 to -24.5 D (mean, -16.7 D). Goal refraction was 0 to + 4 D. Correction was achieved by lensectomy in 5 eyes and lensectomy with intraocular lens implantation in 2 eyes. Primary posterior capsulectomy/subtotal vitrectomy was performed during the primary procedure in 5 eyes (71%). Mean follow-up was 3.8 years (range, 0.5-5.4 years).

RESULTS

Myopia correction averaged 17.3 D. A total of 86% (6 eyes) were corrected within +/- 3 D of the goal refraction and the remaining 14% to within +/- 4 D. Uncorrected visual acuity improved postoperatively in all 7 eyes, albeit modestly (average gain 0.14 Snellen fraction; gain from a mean 20/2550 to a mean 20/130). Myopic regression averaged approximately 0.43 D/year. Capsular opacification necessitated YAG-laser membranectomy in the 2 eyes that had preservation of the posterior capsule at the primary procedure. Retinal detachment has not occurred in any of the eyes during the follow-up period.

CONCLUSIONS

Refractive myopic lensectomy reduced high anisometropia and improved functional vision in children who have high myopia beyond the range of excimer laser correction and who will not wear glasses. Further study is indicated to determine the long-term safety of this procedure in similar pediatric populations.

Pediatric refractive surgery

Refractive surgery in children is controversial; it is mainly performed when conventional treatment has failed. The primary indications are anisometropic amblyopia and bilateral high myopia. The major areas of concern are unstable refraction due to ongoing growth of the eye, and long-term implications. The most popular procedures are photorefractive keratectomy or laser-assisted subepithelial keratomileusis followed by laser-assisted in situ keratomileusis. There are technical difficulties involved in performing these procedures because of smaller palpebral apertures and the need for general anesthesia in younger children. Reports of minimal haze and regression in children who have undergone photorefractive keratectomy for high myopia are of interest, as this is contrary to what occurs in adults. Additional study may result in better long-term data and further indications for refractive surgery in children.

Refractive surgery for high bilateral myopia in children with neurobehavioral disorders: 2. Laser-assisted subepithelial keratectomy (LASEK)

INTRODUCTION

A subpopulation of children with high myopia and neurobehavioral disorders is noncompliant with spectacle wear and ill-suited to correction using contact lenses. We report the results of refractive surgery in a series of these children treated bilaterally using excimer laser technology.

METHODS

Clinical course and outcome data were collated prospectively in a group of 9 children (mean age, 10.2 years; range, 3-16 years) with neurobehavioral disorders exacerbated by chronic noncompliance with spectacle wear, causing profoundly low functional vision. Myopia in the 18 eyes ranged from -3.75 to -11.5 D (mean -16.6 D) and the desired refraction was approximately +1D. Correction was achieved by bilateral laser-assisted subepithelial keratectomy (ie, LASEK) performed under brief general anesthesia. Mean follow-up was 17 months (range, 6-36 months).

RESULTS

Myopia correction averaged 7.9 D. Eighty-nine percent (16/18 eyes) were corrected to within +/-1 D of goal refraction. Uncorrected acuity improved postoperatively in all 18 eyes, with commensurate gains in behavior and environmental visual interaction in 88% (15/17 children). Myopic regression averaged approximately 0.8 d/year. the only complication encountered was mild (1+) corneal haze in 35% of treated eyes.

DISCUSSION/CONCLUSIONS

Bilateral excimer laser surgery is effective for improving functional vision substantially in highly myopic, neurobehaviorally impaired children who have difficulties wearing glasses. Myopic regression is common. Further study is indicated to determine the long-term safety of these and alternative refractive procedures in similar pediatric populations.

Refractive surgery for high bilateral myopia in children with neurobehavioral disorders: 1. Clear lens extraction and refractive lens exchange

INTRODUCTION

A subpopulation of children with high myopia and neurobehavioral disorders is noncompliant with spectacle wear and ill-suited to correction using contact lenses. We report the results of refractive surgery in a series of these children treated using lensectomy alone (clear lens extraction), or lensectomy with simultaneous implantation of an intraocular lens (refractive lens exchange).

METHODS

Clinical course and outcome data were collated prospectively in a group of 13 children (mean age 10.4 years, range 1 to 18 years) with neurobehavioral disorders exacerbated by chronic noncompliance with spectacle wear, causing profoundly low functional vision. Myopia in the 26 eyes ranged from -14.25 to -26.00 D (mean -19.1 D). Goal refraction was approximately +1 D. Correction was achieved by lensectomy alone in 10 eyes, and lensectomy with intraocular lens implantation in 16 eyes. Primary posterior capsulectomy/subtotal vitrectomy was performed during the primary procedure in 11 eyes (42%). Mean follow-up was 4.5 years (range 1.3 to 7.5 years).

RESULTS

Myopia correction averaged 19.9 D. Eighty-one percent (21 eyes) were corrected to within +/-2 D of goal refraction and the remaining 19% (5 eyes) to within +/-4 D. Uncorrected acuity improved substantially (ie, an average 2 log units) in all 26 eyes, with commensurate gains in behavior and environmental visual interaction in 85% [corrected] of children (11/13) [corrected] Myopic regression averaged -0.16 D/year. Capsular regrowth and/or opacification necessitated vitrector or YAG-laser membranectomy in 13 [corrected] eyes (50%) [corrected] Focal retinal detachment (successfully repaired) occurred after eye contusion in one eye (4%) with cicatricial retinopathy of prematurity.

CONCLUSIONS

Bilateral refractive lensectomy is effective for improving functional vision in neurobehaviorally impaired children who have high myopia (beyond the range of excimer laser correction: see companion publication) and difficulties wearing glasses. Posterior capsule regrowth/opacification is common, necessitating secondary membranectomy. Further study is indicated to determine the long-term safety of this procedure in similar pediatric populations.

Treatment options for anisohyperopia

PURPOSE

To investigate the success of conventional methods in the treatment of anisohyperopic amblyopia.

METHODS

A retrospective chart review of all patients with anisohyperopic amblyopia seen at the UCSD/ Ratner Children's Eye Center during a 42-month period was performed. The charts of 35 patients aged 3 to 14 years (mean age, 6.8 years) with 1.5 to 6.5 diopters of anisohyperopia were reviewed. Main outcome measures were the difference in refractive error and the pre- and post-treatment Snellen equivalent distance acuities. Treatment consisted of one or a combination of the following: spectacles, contact lenses, patching, and atropine. Binocularity was determined using the Titmus test. Compliance to treatment also was rated.

RESULTS

Thirteen (37.1%) patients were treated with spectacles alone, 11 (31.5%) were treated with a combination of atropine and patching, 8 (22.8%) were treated with patching alone, 2 (5.7%) received blurring contact lenses, and 1 (2.9%) patient was treated with atropine alone. The average pretreatment visual acuity was 20/108, with an improvement to an average of 20/27 at the termination of treatment. Ninety-four percent of the patients obtained a visual acuity of 20/40 or better.

CONCLUSIONS

Conventional methods of treatment are effective in improving vision and binocular status in anisohyperopia. Depending on the patient, only spectacles may be required.

Refractive laser surgery in children with coexisting medical and ocular pathology

PURPOSE

To report the visual, refractive, and functional outcomes of photorefractive keratectomy (PRK) and of laser-assisted subepithelial keratectomy in a group of children with significant refractive error and underlying medical conditions or ocular pathology who were noncompliant with traditional management.

SETTING

Nonhospital surgical facility and a hospital clinic.

METHODS

This case series comprised 5 individual cases of anisometropic amblyopia and/or high myopia. Underlying medical and ocular conditions were as follows: upper eyelid hemangioma with oblique myopic astigmatism, Pelizaeus-Merzbacher leukodystrophy with nystagmus, Klippel-Trenaunay-Weber syndrome with glaucoma, incontinentia pigmenti with unilateral optic nerve atrophy, and Goldenhar syndrome with unilateral optic nerve hypoplasia. Photorefractive keratectomy or LASEK was performed in 6 eyes of 5 patients. Age range at the time of surgery was 1.0 to 7.0 years. All procedures were performed under general anesthesia.

RESULTS

Best corrected visual acuity improved by 2 lines in 2 patients and 1 line in 2 patients by 6 months after surgery. Stereopsis and/or fusional status improved in 3 patients. Amblyopia treatment compliance improved in 1 patient. Alignment improved without strabismus surgery in 2 cases. A functional vision survey demonstrated a positive effect on the ability of all 5 children to function in their environment.

CONCLUSION

During the period of visual cortical plasticity, refractive surgery, by eliminating the refractive component of amblyopia and by promoting fusional ability, provides considerable improvement in children, even those with underlying medical conditions associated with ocular pathology.

Amblyopia: diagnostic and therapeutic options

PURPOSE

To provide an overview of the current state of knowledge of amblyopia and highlight recent advances in diagnosis and treatment.

DESIGN

Review of literature and perspective.

METHODS

MEDLINE search for amblyopia, with a review of all recent literature adding authors' personal perspectives on the findings.

RESULTS

Increased awareness of amblyopia and better screening techniques are required to identify children who are at risk for amblyopia at a younger age. Randomized, controlled trials have established atropine penalization as a viable alternative to occlusion therapy, have suggested that less treatment may be better tolerated and as effective as more traditionally used dosages, and have found no compelling evidence that treatment is beneficial clinically for older (over age 10) children with amblyopia.

CONCLUSION

Early detection and treatment of amblyopia can improve the chances for a successful visual outcome. Considering that the conditions that place a patient at risk for amblyopia can be identified, that amblyopia responds to treatment, and that well-tolerated treatments for the condition are now recognized, it is not unreasonable to imagine that, in the near future, severe amblyopia could be eliminated as a public health problem.

Comparative study of 2 anesthesia techniques for pediatric refractive surgery

PURPOSE

To compare the effectiveness of 2 anesthesia techniques for pediatric refractive surgery, propofol/fentanyl and ketamine/midazolam.

SETTING

Department of Ophthalmology, Magraby Eye & Ear Center, Muscat, Oman.

METHODS

This prospective clinical study was of children ranging in age range from 3 to 12 years who were followed for myopic anisometropia with amblyopia after failure of conventional correction or patients with superficial stromal corneal opacities. The children were scheduled to have refractive surgery under general anesthesia using propofol/fentanyl (P/F group) or ketamine/midazolam (K/M group). All drugs were administered intravenously.

RESULTS

Thirty patients were included in the study and were divided randomly into 2 equal groups. Both groups were comparable in age, weight, sex, duration of anesthesia, and duration of surgery. Time to complete recovery was significantly shorter in the P/F group. The hemodynamic changes observed in this study were not of clinical significance. Three patients in the P/F group showed arterial oxygen (O2) saturation of less than 90% and supplemental O2 was given by nasal cannula. The incidence of postoperative agitation and vomiting was significantly higher in the K/M group, while the need for jaw thrust was significantly higher in the P/F group. The difference between both groups in the ophthalmologist satisfaction score was not significant.

CONCLUSIONS

Propofol offered some advantages for brief procedures outside the traditional operating rooms. It is short acting, and has a rapid offset resulting in shorter postoperative monitoring and a smoother recovery profile. It has greater potential for respiratory depression than ketamine. Hence, greater vigilance and experience with the pediatric airway is recommended with its use.

Can We Utilize Photorefractive Keratectomy to Improve Visual Acuity in Adult Amblyopic Eyes?

PURPOSE

To report the results of photorefractive keratectomy (PRK) in adult amblyopic patients.

DESIGN

Noncomparative case series.

PARTICIPANTS

Thirty-eight amblyopic eyes of 36 adult patients who had undergone PRK ranging from -14.63 diopters (D) to +3.75 D (mean, -6.38+/-4.10) were analyzed.

METHODS

Preoperative and postoperative (1, 3, and 6 months) refractions and measurements of the best spectacle-corrected visual acuity (BSCVA) were reviewed. Statistical evaluation was performed using a paired Student's t test.

MAIN OUTCOME MEASURES

Best-corrected visual acuity before and after PRK.

RESULTS

Before PRK, BSCVA ranged between 0.2 and 0.7 lines (mean, 0.60+/-0.13). One month after PRK, BSCVA ranged between 0.2 and 1.2 lines (mean, 0.77+/-0.24), with a significant difference (P = 3x10(-5)). Three months after PRK, BSCVA ranged between 0.15 and 1.15 lines (mean, 0.84+/-0.23), with a significant difference (P = 5x10(-7)). Six months after PRK, BSCVA ranged between 0.25 and 1.3 lines (mean, 0.88+/-0.25), with a significant difference (P = 8x10(-8)).

CONCLUSIONS

Our study does not imply that refractive surgery should or may be performed in young children but, rather, that adults wishing to undergo refractive surgery may undertake such procedures despite an amblyopic eye thought to be refractory to visual rehabilitation by conventional methods, such as spectacles and contact lenses.

Correction of large amblyopiogenic refractive errors in children using the excimer laser

PURPOSE

We sought to determine whether laser subepithelial keratomileusis (LASEK) and photorefractive keratectomy (PRK) are effective methods for correcting amblyopiogenic refractive errors in children.

METHODS

Thirty-six eyes in 35 amblyopic children, who ranged in age from 4 to 16 years (mean, 8.4 years), received treatment for large magnitude ametropia. Seventy-two percent (25/35) of the children had a neurobehavioral disorder and/or were noncompliant with spectacle or contact lens wear. Myopia ranged from -3.25 to -24.25 D (mean, -11.48 D); one patient had hyperopia of +5.87 D. Correction was tailored to match the refractive error of the nonamblyopic eye. VISX Star S2/S3 excimer lasers were used in manual or auto-tracking modes, and corneal centration was achieved using brief, general anesthesia. Mean follow-up was 29.2 months (range, 4-42 months).

RESULTS

Myopia correction averaged -8.95 +/- 2.89 D (range, -3.25 to -15.50). Eighty-nine percent (31 children) were corrected to within +/- 1.00 D of goal refraction and the remaining 11% to within 2.0 D of the goal (most were undercorrected). Acuity improved postoperatively in 97%; by 1 optotype line in 37% and by 2 or more in 60%. No child lost acuity. Binocularity improved in 69% (24/35) and remained the same in 31%. Corneal haze measured grade 0-1 in 78%, grade 2 in 14%, and grade 3-4 in 8%. Myopic regression exceeding congruent with 1.0 D/year (0.08 D/month) occurred in 50% (18/36) of eyes treated. No substantial differences were observed in PRK- (n = 18) versus LASEK- (n = 17) treated children.

CONCLUSIONS

Laser refractive surgery is effective for correcting anisometropic myopia in amblyopic children. Recurrence of myopia is common. Further study is indicated to determine long-term stability and safety of the procedure in this population.