Sharon F. Freedman

The Ahmed Valve in refractory pediatric glaucoma

PURPOSE To evaluate the efficacy of the Ahmed Glaucoma Valve implant in pediatric patients with refractory glaucoma. METHODS A retrospective chart review was conducted of 27 eyes from 23 consecutive pediatric patients (younger than 18 years) with refractory glaucoma treated with Ahmed Glaucoma Valve implant placement. The main outcome measure was time after surgery without failure. Success was defined as an intraocular pressure of 21 mm Hg or less without visually devastating complications or additional glaucoma surgery (exclusive of tube revision). Previous cycloablation, which was present in a subset of eyes, was examined as a possible influence on postoperative intraocular pressure control, glaucoma medication dependence, and surgical success. RESULTS The median patient age was 4.8 years (range, 0.3 to 16.8 years), with a follow-up of 3 to 31 months (mean, 12.6 +/- 8.2 months). Intraocular pressure was reduced from a preoperative mean of 32.8 +/- 7.5 mm Hg to 16.7 +/- 5.4 mm Hg at 18 months postoperatively, with an overall success rate of 85.2% at last follow-up. Cumulative probabilities of success by Kaplan-Meier analysis were 90.6% at 12 months and 58.3% at 24 months. Compared with those that did not undergo previous cycloablation, eyes that had undergone previous cycloablation had a lower mean postoperative intraocular pressure at 3- and 6-month follow-up (P < .001 and P = .057, respectively) and required fewer glaucoma medications at postoperative examination time points up to 18 months (P < or = .01 at each time point). Fifteen eyes (56%) required glaucoma medications after surgery. The most common complication was corneal-tube contact, which occurred in five eyes (18.5%). One eye with a wound leak required anterior chamber reformation. Retinal detachment occurred in one aphakic eye 2 years postoperatively, resulting in loss of vision. One eye with neovascular glaucoma required enucleation after an enlarging (presumably preexisting) medulloepithelioma was discovered. CONCLUSIONS Ahmed Glaucoma Valve implantation is a useful therapy for the treatment of refractory pediatric glaucoma, and it may be safely used in a subgroup of eyes with uncontrolled intraocular pressure despite previous cycloablation procedures.

Optical coherence tomography in the eyes of normal children.

OBJECTIVE To collect a normative database of macular thickness, retinal nerve fiber layer (RNFL) thicknesses, and optic nerve topography in the healthy eyes of children aged 3 to 17 years using optical coherence tomography (OCT) measurements. METHODS Scans were obtained for 286 healthy children (black, 114; white, 154; other, 18). Each child had a dilated eye examination, an axial length measurement using the IOL Master (Carl Zeiss Meditec, Dublin, California), and OCT measurements using the fast macular map, fast RNFL thickness, and fast optic disc protocols of the Stratus OCT (OCT-3; Carl Zeiss Meditec). RESULTS Black children had smaller macular volume and foveal thickness, larger RNFL thickness, and larger cup-disc area ratios compared with white children. Macular volume and average outer macular thickness correlated negatively with axial length in white children. Foveal thickness correlated positively with age in black children only. Average RNFL correlated negatively with axial length in white children only (P < .05 for all). Normative data for all variables were recorded and compared with reported adult values. CONCLUSIONS Stratus OCT-3 measurements of macular and RNFL thickness and optic nerve topography vary with race, axial length, and age in healthy children. Normative pediatric OCT data should facilitate the use of OCT in assessing childhood glaucoma and other diseases.

Optimizing Hand-held Spectral Domain Optical Coherence Tomography Imaging for Neonates, Infants, and Children

PURPOSE To describe age-related considerations and methods to improve hand-held spectral domain optical coherence tomography (HH-SD OCT) imaging of eyes of neonates, infants, and children. METHODS Based on calculated optical parameters for neonatal and infant eyes, individualized SD OCT scan parameters were developed for improved imaging in pediatric eyes. Forty-two subjects from 31 weeks postmenstrual age to 1.5 years were imaged with a portable HH-SD OCT system. Images were analyzed for quality, field of scan, magnification, and potential clinical utility. RESULTS The axial length of the premature infant eye increases rapidly in a linear pattern during the neonatal period and slows progressively with age. Refractive error shifts from mild myopia in neonates to mild hyperopia in infants. These factors affect magnification and field of view of optical diagnostic tools applied to the infant eye. When SD OCT parameters were corrected based on age-related optical parameters, SD OCT image quality improved in young infants. The field of scan and ease of operation also improved, and the optic nerve, fovea, and posterior pole were successfully imaged in 74% and 87% of individual eye imaging sessions in the intensive care nursery and clinic, respectively. No adverse events were reported. CONCLUSIONS SD OCT in young children and neonates should be customized for the unique optical parameters of the infant eye. This customization, not only improves image quality, but also allows control of the density of the optical sampling directed onto the retina.

Agreement among pediatric ophthalmologists in diagnosing plus and pre-plus disease in retinopathy of prematurity

PURPOSE Plus disease has become the major criterion for laser treatment in infants with retinopathy of prematurity (ROP), but its assessment is subjective. Our purpose was to compare quadrant-level and eye-level assessment of plus disease and pre-plus disease among 3 experienced ROP examiners and to report their rate of agreement. METHODS One hundred eighty-one high-quality RetCam images from premature infants were graded by 3 of the authors. Dilation and tortuosity were judged separately using a scale of normal or sufficiently abnormal to meet criteria for pre-plus or plus disease. RESULTS There was disagreement on the presence of plus disease for 18 images (10%), on tortuosity sufficient for plus disease (plus tortuosity) for 26 images (14%), and on dilation sufficient for plus disease (plus dilation) for 26 images (14%). Of 67 images judged to have pre-plus disease or worse, there was disagreement on the presence of plus disease for 18 images (27%), on plus tortuosity for 25 images (37%), and on plus dilation for 21 images (31%). For distinguishing plus or pre-plus disease from normal, there was disagreement on pre-plus tortuosity for 38 of 181 images (21%) and on pre-plus dilation for 58 of 181 images (32%). CONCLUSIONS Three experienced ROP examiners disagreed frequently on the diagnosis of plus or pre-plus disease when evaluating cropped clinical photographs of infants, many of which had borderline plus disease. Further study is required to determine the implications of these observations on clinical decision making.

Dynamics of Human Foveal Development after Premature Birth

PURPOSE To determine the dynamic morphologic development of the human fovea in vivo using portable spectral domain-optical coherence tomography (SD-OCT). DESIGN Prospective, observational case series. PARTICIPANTS Thirty-one prematurely born neonates, 9 children, and 9 adults. METHODS Sixty-two neonates were enrolled in this study. After examination for retinopathy of prematurity (ROP), SD-OCT imaging was performed at the bedside in nonsedated infants aged 31 to 41 weeks postmenstrual age (PMA) (= gestational age in weeks + chronologic age) and at outpatient follow-up ophthalmic examinations. Thirty-one neonates met eligibility criteria. Nine children and nine adults without ocular pathology served as control groups. Semiautomatic retinal layer segmentation was performed. Central foveal thickness, foveal to parafoveal (FP) ratio (central foveal thickness divided by thickness 1000 μm from the foveal center), and 3-dimensional thickness maps were analyzed. MAIN OUTCOME MEASURES In vivo determination of foveal morphology, layer segmentation, analysis of subcellular changes, and spatiotemporal layer shifting. RESULTS In contrast with the adult fovea, several signs of immaturity were observed in the neonates: a shallow foveal pit, persistence of inner retinal layers (IRLs), and a thin photoreceptor layer (PRL) that was thinnest at the foveal center. Three-dimensional mapping showed displacement of retinal layers out of the foveal center as the fovea matured and the progressive formation of the inner/outer segment band in the opposite direction. The FP-IRL ratios decreased as IRL migrated before term and minimally after that, whereas FP-PRL ratios increased as PRL subcellular elements formed closer to term and into childhood. A surprising finding was the presence of cystoid macular edema in 58% of premature neonates that appeared to affect inner foveal maturation. CONCLUSIONS This study provides the first view into the development of living cellular layers of the human retina and of subcellular specialization at the fovea in premature infant eyes using portable SD-OCT. Our work establishes a framework of the timeline of human foveal development, allowing us to identify unexpected retinal abnormalities that may provide new keys to disease activity and a method for mapping foveal structures from infancy to adulthood that may be integral in future studies of vision and visual cortex development. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.

Aqueous shunt devices compared with trabeculectomy with Mitomycin-C for children in the first two years of life☆

PURPOSE To compare the outcomes of children 24 months of age or younger treated with aqueous shunt devices or with mitomycin-C (MMC) trabeculectomy. DESIGN Retrospective, age-matched, comparative case series. METHODS Forty-six eyes of 32 patients with mean age of 7.0 +/- 5.1 month (range, 1 to 22 months) and uncontrolled glaucoma, which received an aqueous shunt device (Ahmed glaucoma valve or Baerveldt implant), compared with 24 eyes of 19 patients with mean age of 5.3 +/- 4.8 months (range, 0.5 to 24 months), which received an MMC trabeculectomy. Surgical success was defined as intraocular pressure < 23 mm Hg on maximal glaucoma medication, no further glaucoma surgery performed or recommended, no devastating complication, and stable ocular dimensions (axial length and corneal diameter). RESULTS Cumulative probabilities of success were 87% +/- 5.0% for the aqueous shunt group compared with 36% +/- 8.0% success in the trabeculectomy group at 12 months and 53% +/- 12% in the aqueous shunt group compared with 19% +/- 7% in the trabeculectomy group at 72 months (chi(2) of 23.5, P <.0001). Aqueous shunt implantation was associated with significantly more postoperative complications requiring a return to the operating room (21 of 46 eyes, 45.7%) compared with trabeculectomy with MMC (3 of 24 eyes, 12.5%, P =.0074). The most common postoperative procedure in the aqueous shunt group was tube repositioning, performed in 16 of 46 eyes (34.8%). CONCLUSIONS Aqueous shunt implantation offers a significantly greater chance of successful glaucoma control in the first 2 years of life, compared with trabeculectomy with MMC. However, the enhanced success with aqueous shunt devices is associated with a higher likelihood of postoperative complications requiring surgical revision, most commonly tube repositioning.

Insights into Advanced Retinopathy of Prematurity Using Handheld Spectral Domain Optical Coherence Tomography Imaging

PURPOSE To elucidate the subclinical anatomy of retinopathy of prematurity (ROP) using spectral domain optical coherence tomography (SD OCT). DESIGN Prospective, observational case series. PARTICIPANTS Three low-birth-weight, severely premature infants. METHODS Clinical examination was performed using a portable slit lamp and indirect ophthalmoscope. Imaging was performed by using a handheld SD OCT device and Retcam (Clarity Medical Systems, Pleasanton, CA) or video-indirect recording. Spectral domain optical coherence tomography imaging was conducted without sedation at the bedside in the neonatal intensive care unit on 1 patient. The other 2 patients had an examination under anesthesia with SD OCT imaging in the operating room. MAIN OUTCOME MEASURES In vivo determination of vitreoretinal morphology, anatomy, and pathology by clinical examination, imaging, and SD OCT. RESULTS Linear and volumetric imaging was achieved with the handheld system in infant eyes despite tunica vasculosa lentis and vitreous bands. Imaging was not possible in eyes with notable vitreous hemorrhage. Analysis of SD OCT images revealed preretinal structures (ranging from 409 to 2700 microm in width and 212 to 440 microm in height), retinoschisis, and retinal detachment in the posterior pole of patients with advanced ROP. Both the retinoschisis and the preretinal structures were not identified on conventional examination or imaging by expert pediatric ophthalmologists. The preretinal structures varied in location and size, and may represent preretinal fibrovascular proliferation. Some were found in close proximity to blood vessels, whereas others were near the optic nerve. CONCLUSIONS Handheld SD OCT imaging can be performed on the sedated or nonsedated neonate and provides valuable subclinical anatomic information. This novel imaging modality can reveal the location and extent of posterior ROP pathology not evident on standard examination. This could affect future clinical decision-making if studies validate a management strategy based on findings from this imaging technique.

The Infant Aphakia Treatment Study: Design and Clinical Measures at Enrollment

OBJECTIVE To compare the use of contact lenses and intraocular lenses (IOLs) for the optical correction of unilateral aphakia during infancy. METHODS In a randomized, multicenter (12 sites) clinical trial, 114 infants with unilateral congenital cataracts were assigned to undergo cataract surgery with or without IOL implantation. Children randomized to IOL treatment had their residual refractive error corrected with spectacles. Children randomized to no IOL treatment had their aphakia treated with a contact lens. MAIN OUTCOME MEASURES Grating acuity at 12 months of age and HOTV visual acuity at 4 1/2 years of age. APPLICATION TO CLINICAL PRACTICE This study should determine whether either treatment for an infant with a visually significant unilateral congenital cataract results in a better visual outcome. RESULTS Enrollment began December 23, 2004, and was completed January 16, 2009. The median age at the time of cataract surgery was 1.8 months. Fifty patients were 4 to 6 weeks of age at the time of enrollment; 32, 7 weeks to 3 months of age; and the remaining 32, more than 3 to less than 7 months of age. Fifty-seven children were randomized to each treatment group. Eyes with cataracts had shorter axial lengths and steeper corneas on average than the fellow eyes. CONCLUSIONS The optimal optical treatment of aphakia in infants is unknown. However, the Infant Aphakia Treatment Study was designed to provide empirical evidence of whether optical treatment with an IOL or a contact lens after unilateral cataract surgery during infancy is associated with a better visual outcome.

Macular translocation with 360-degree peripheral retinectomy impact of technique and surgical experience on visual outcomes.

Purpose To evaluate the impact of technique and surgical experience on complications and outcomes of macular translocation surgery with 360-degree peripheral retinectomy (MTS360). Methods Twenty-six consecutive patients underwent MTS360 in a prospective study of macular translocation surgery for subfoveal choroidal neovascularization (CNV) in eyes with age-related macular degeneration (ARMD). Data gathered included intraoperative and postoperative events and pre- and postoperative standardized visual acuity recorded as number of letters read. Because the surgical technique changed particularly during the first 16 cases, patients were grouped into an evolving treatment group of the first 16 patients (Group 1) and a modified treatment group of the final 10 patients (Group 2). Results As techniques evolved in this series, ease of surgery increased. There were significant decreases in surgery duration and in number of retinotomies required to induce artificial retinal detachment. Number of postoperative retinal detachments decreased from five in Group 1 to none in Group 2. Change in visual acuity was significantly different between the two groups: Group 1 had an average loss of 14 letters (<3 lines) and Group 2 an average gain of 3 letters (<1 line) (P < 0.05). Average postoperative visual acuity was significantly better for Group 2 (68 letters, approximately 20/80) than for Group 1 (47 letters, approximately 20/250) (P < 0.01). Conclusion Surgical experience and a progressively modified surgical technique decreased perioperative complications and improved visual outcomes after MTS360. With modified MTS360, central vision has been salvaged for almost 1 year of follow-up in patients presenting with vision loss from subfoveal CNV and ARMD.

A comparison of the rate of refractive growth in pediatric aphakic and pseudophakic eyes

OBJECTIVE To compare the rate of refractive growth in pseudophakic childrens eyes to that of aphakic eyes. DESIGN Multicenter, retrospective observational case series. PARTICIPANTS 83 patients with pseudophakic eyes (100 eyes) and 74 patients with aphakic eyes (106 eyes), with an age of surgery between 3 months and 10 years and a minimum follow-up time of 3 years or more, depending on the age at surgery. METHODS A logarithmic model was used to analyze the rate of refractive growth for each eye. MAIN OUTCOME MEASURES Age at surgery, intraocular lens power, intraocular lens A-constant, initial postoperative refraction, final refraction, and final age. RESULTS Overall, pseudophakic eyes showed a lesser rate of refractive growth than aphakic eyes (-4.6 diopter vs. -5.7 diopter, P = 0.03). This trend was also present but less significant when the eyes were grouped into those less than 6 months of age at surgery (-3.3 diopter vs. -4.6 diopter, P = 0.09) and older patients (-5.0 diopter vs. -6.1 diopter, P = 0.07). However, the mean quantity of myopic shift was greater in pseudophakic eyes than in aphakic eyes (-5.26 diopter vs. -4.54 diopter), despite shorter follow-up times in the pseudophakic eyes. This is due to the optical effects of a constant intraocular lens power in a growing eye. CONCLUSIONS Pediatric pseudophakic eyes have a slightly lesser rate of refractive growth than aphakic eyes. The new rate values should be used for predicting future refractions in these eyes.