Laura B. Enyedi

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.

Imaging the Infant Retina with a Hand-held Spectral-Domain Optical Coherence Tomography Device

PURPOSE To evaluate and treat infant retina through the use of a hand-held spectral-domain optical coherence tomography (SD OCT) device in selected cases of Shaken Baby syndrome (SBS). DESIGN Observational case series. METHODS A novel SD OCT system was optimized and evaluated for infant imaging. An adult eye was imaged with both a standard clinical SD OCT system and the hand-held system. Four eyes of two infants with a history of SBS were imaged with the hand-held system. One infant was imaged again during follow-up examinations. Robust image processing algorithms were developed to create high-quality images. Images were assessed for usefulness in demonstrating pertinent morphologic features. RESULTS The novel SD OCT unit proved effective for data acquisition and comparable with conventional chin-rest SD OCT. Rapid data acquisition limited motion artifact within the B-scan, although there was slight motion between B scans. The SD OCT images provided previously unseen details with regard to the morphologic features of retinal lesions in these infant eyes. This information influenced prognosis and management. CONCLUSIONS As with adults, the hand-held customized SD OCT proved to be an invaluable tool in the differentiation of disease processes or injury in these eyes under study. SD OCT imaging systems may be considered a useful adjunct to RetCam fundus photography for assessment and clinical management in cases of SBS.

Refractive changes after pediatric intraocular lens implantation

PURPOSE To report refractive changes after cataract surgery and intraocular lens implantation in infants and children. METHODS In an ongoing prospective study, the refractive errors of all patients younger than 18 years undergoing intraocular lens implantation were determined at 6 weeks, 3 months, 6 months, and 1 year, and at least yearly thereafter. All patients with greater than 6 months of follow-up were included in the study. RESULTS Eighty-three eyes of 81 patients were identified. Cataracts were traumatic in 32 eyes (38%) and developmental in 42 eyes (50%). At implantation, the mean (+/-SD) age was 6.3 +/- 4.6 years (range, 9 months to 17 years). The mean follow-up was 26.6 months (range, 6 months to 6.6 years). Patients 0 to 2 years old at the time of implantation demonstrated a mean myopic shift of -3.00 diopters during a mean follow-up period of 2.5 years. Patients 2 to 6 years old at the time of implantation demonstrated a mean myopic shift of -1.50 diopters in a similar follow-up period. Children aged 6 to 8 years experienced a mean myopic shift of -1.80 diopters during a mean follow-up period of 3.0 years, while children older than 8 years at the time of intraocular lens implantation experienced a mean myopic shift of -0.38 diopters during a mean follow-up period of 1.8 years. On average, the operated-on eye showed a greater mean myopic shift than the fellow eye. No statistically significant differences in refractive change were found in comparing amblyopic to nonamblyopic eyes, traumatic to nontraumatic cataracts, or primary to secondary intraocular lenses. CONCLUSIONS Our data demonstrate a trend toward increasing postoperative myopia in pediatric patients undergoing intraocular lens implantation. This myopic shift is greatest in the younger age groups and persists until at least 8 years of age. There is much variability in the postoperative refractive changes, and predicting exactly when and where the refraction will stabilize for an individual patient is difficult.

An intravitreal device providing sustained release of cyclosporine and dexamethasone.

PURPOSE A device that releases cyclosporine and dexamethasone into the eye for extended periods of time might be beneficial in diseases such as proliferative vitreoretinopathy and uveitis. In this study we examine the pharmacokinetics and toxicity of cyclosporine and dexamethasone combined in an intravitreal sustained-release device and the toxicity of a similar device containing only dexamethasone in rabbits. METHODS Rabbits were divided into three groups for (1) evaluation of the drug tissue levels and device release kinetics following implantation of a device containing 100 micrograms of cyclosporine labeled with 2 microCi of 3H-cyclosporine and 2 mg of dexamethasone; (2) evaluation of the toxicity of this intravitreal device; and (3) evaluation of the toxicity of a similar device containing 2 mg of dexamethasone only. Cyclosporine was measured using a scintillation counter and dexamethasone was measured by high pressure liquid chromatography (HPLC). Toxicity was evaluated by electroretinography, clinical examination, and light microscopy. RESULTS Vitreous concentrations of cyclosporine (+/- standard deviation) averaged 0.06 (+/- 0.02) microgram/ml over 10 weeks. The average dexamethasone concentration over the 10 week period was 2.9 (+/- 0.9) micrograms/ml. Devices containing cyclosporine and dexamethasone released each drug at rates similar to devices containing cyclosporine or dexamethasone alone. Devices containing both cyclosporine and dexamethasone caused reversible depressions in the b-wave amplitude of photopic and scotopic electroretinograms (ERGs). There was no evidence of toxicity associated with the devices containing dexamethasone only. There was no drug-related toxicity evident on clinical or histopathologic examination of eyes with devices containing the combination of cyclosporine and dexamethasone or dexamethasone alone. CONCLUSIONS We conclude that the device maintains potentially therapeutic levels of both cyclosporine and dexamethasone in the vitreous. Reversible electroretinographic abnormalities are attributable to cyclosporine. A sustained-release device containing cyclosporine and dexamethasone may be useful for reducing inflammation in diseases such as proliferative vitreoretinopathy and uveitis.

The effectiveness of latanoprost for the treatment of pediatric glaucoma

PURPOSE Latanoprost is a prostaglandin F2alpha analogue that substantially reduces intraocular pressure (IOP) in adults with open-angle glaucoma or ocular hypertension. The efficacy and safety of latanoprost in children is unknown. We wished to evaluate latanoprost therapy for children with glaucoma. METHODS This was a prospective study of all patients who were given latanoprost at our institution between September 1996 and January 1998. The baseline IOP was compared with the postlatanoprost IOP for each patient, and side effects and any iris color change were noted at each follow-up examination. Responders were defined as those who had at least a 15% IOP reduction on latanoprost, whereas nonresponders showed less than a 15% IOP reduction on latanoprost. RESULTS Fifty-seven eyes of 48 pediatric patients with a variety of glaucoma diagnoses and an average age of 7.1 years were included in the study. Of these, 31 eyes of 31 patients had interpretable IOP data; the mean IOP reduction for this group after the addition of latanoprostwas 0.9% (0.2 mm Hg). Six patients (6 eyes) were responders, with an average IOP reduction of 8.5 mm Hg (34%), whereas the majority of patients (25) were nonresponders. In the responders, there was a good correlation (r = 0.9) between baseline IOP and the magnitude of IOP reduction. Responders were significantly more likely to have juvenile open-angle glaucoma and to be older than nonresponders. Systemic and ocular side effects were infrequent and mild, and no patient had noticeable iris color changes. CONCLUSIONS When used in a group of pediatric patients with a variety of glaucoma diagnoses and on various therapies, latanoprost is effective in only a minority of cases. In selected patients, however, latanoprost shows an impressive ocular hypotensive effect, comparable with that obtained when this drug is used in adults with open-angle glaucoma. This drug appears to be well tolerated in this short-term study of pediatric patients with glaucoma.

Goniotomy for glaucoma secondary to chronic childhood uveitis

PURPOSE To evaluate the safety and efficacy of standard goniotomy surgery for young patients with refractory glaucoma associated with chronic childhood uveitis. DESIGN Interventional case series. METHODS We retrospectively reviewed all goniotomies performed at our institution for patients with a diagnosis of refractory glaucoma associated with chronic childhood uveitis from 1994 to 2000 (this was our first-line surgery for such patients during these years). Uveitis was medically controlled in all cases for at least 6 weeks before surgery. The main outcome measure was time after surgery without failure. Success was defined as final intraocular pressure (IOP) <or= 21 mm Hg after one or two goniotomies without need for further surgical intervention. Follow-up was >or=6 months or until surgical failure. RESULTS Nineteen goniotomies were performed on 16 eyes (12 patients). Diagnoses included uveitic glaucoma associated with juvenile rheumatoid arthritis, sarcoidosis, and idiopathic uveitis. The mean patient age at first goniotomy was 15.3 years (range, 6.5-30), with mean follow-up 32.4 months (range, 6-84). Cases included were phakic (10 eyes), aphakic (four eyes), and pseudophakic (two eyes). The mean preoperative IOP was 32.3 +/- 4.6 mm Hg. Surgical success was achieved in 12 of 16 (75%) eyes with a mean postoperative IOP of 12 +/- 2.5 mm Hg for these eyes (mean IOP reduction, 20.0 mm Hg, P <.0001). In 10 of 16 eyes (60%), surgical success was achieved after a single goniotomy. Uveitis was stable in all patients after the early post-operative period. Successful eyes used, on average, 1.4 +/- 1.1 glaucoma medications after goniotomy. Complications were mild and included transient hyphema in nine cases (56%) and worsening of a preexisting cataract in a single case (6%). CONCLUSIONS Goniotomy represents a safe and effective first-line surgery for young patients with refractory glaucoma associated with chronic uveitis, although the majority of patients require glaucoma medication after the procedure.

Latanoprost for the treatment of pediatric glaucoma

Latanoprost is a prostaglandin F(2alpha) analog that reduces intraocular pressure (IOP) by 20-40% in adults with open-angle glaucoma or ocular hypertension. The efficacy and safety of latanoprost in children has not been widely reported, but there are at least three peer-reviewed publications involving the use of this drug in the treatment of pediatric patients with glaucoma. Most of the patients in these studies showed disappointingly little IOP effect from this drug, but some children, particularly older children and those with juvenile-onset open-angle glaucoma, do have a significant ocular hypotensive effect with latanoprost. Systemic and ocular side effects in children on latanoprost are infrequent and mild.

Central corneal thickness in children: Racial differences (black vs. white) and correlation with measured intraocular pressure.

PurposeTo test the hypotheses that the mean central corneal thickness (CCT) of healthy black children is thinner than that of healthy white children and to confirm the relationship between increased CCT and measured intraocular pressure (IOP) in children. MethodsThis prospective observational case series included 178 eyes of 92 children aged 9 months to 17 years without anterior segment abnormalities or a clinical diagnosis of glaucoma. CCT was measured by ultrasonic pachymetry and IOP was measured by Goldmann or Tono-pen technique. ResultsThe mean CCT for the 102 eyes of 52 white children was 562±35 μm versus 543±37 μm for the 66 eyes of 35 black children (P=0.02). There was a positive relationship between CCT and IOP (P=0.0002). For every 100 μm increase in CCT, the IOP increased by 2.2±0.6 mm Hg. ConclusionsThe mean CCT of black children is thinner than that of white children. There is a positive relationship between increasing measured IOP and CCT among children with normal corneas and anterior segments. The interpretation of elevated IOP in eyes with abnormal anterior segment anatomy and thickened corneas awaits further study.

Correlation between Optical Coherence Tomography and glaucomatous optic nerve head damage in children

Aim: To compare analysis of macular and nerve fibre layer thickness by optical coherence tomography (OCT) with optic nerve head (ONH) morphology based on stereophotography. Design: Prospective observational case–control series. Methods: Normal and glaucomatous eyes of children (age 4–17 years) were scanned using Stratus OCT (Carl Zeiss Meditec, Dublin, California, USA). Fast macular and retinal nerve fibre layer (RNFL) thickness map were performed on 372 eyes of 222 children. ONH stereophotographs were taken and evaluated by two masked observers using a grading system of 0 to 5 based on both cupping ratio and morphology. OCT3 analyses were compared across ONH grades for different areas around the macula and the peripapillary RNFL. Results: Analysis included OCT values and ONH grading for 139 eyes of 139 children. There was a negative correlation between ONH grade and both macular thickness and RNFL thickness in all areas measured. There was a difference in the correlation identified for black versus white children. Conclusion: OCT measurements of RNFL and macular thickness declined with increasing grade of glaucomatous damage seen on stereophotographs in black and white children. Further study will help quantify the value of OCT in the diagnosis and management of paediatric glaucoma.

Safety and Efficacy of Silicone Rod Frontalis Suspension Surgery for Childhood Ptosis Repair

PURPOSE To evaluate the safety and efficacy of silicone rod frontalis suspension surgery for childhood ptosis. METHODS The authors retrospectively studied 89 consecutive children (110 eyelids) who had silicone rod frontalis suspension surgery for ptosis at Duke University Eye Center from 1983 to 2004. Marginal reflex distance1 (MRD1) elevation of 2 mm or more (vs preoperative MRD1) was considered satisfactory. MRD1 was measured as the vertical distance from the corneal light reflex in primary gaze to the upper eyelid margin. The postoperative eyelid symmetry (< or = 1 mm = satisfactory) was the difference between the MRD1 of the surgical and fellow eyelid. RESULTS Median age at surgery was 45 months (range: 3 to 223 months) and median follow-up was 17 months (range: 1 to 88 months). Ptosis types (number of eyelids) were unilateral congenital (53), bilateral congenital (30), third nerve palsy (16), Marcus Gunn jaw wink (7), trauma (2), and myasthenia gravis (2). Median MRD1 elevation was 2 mm or greater for all ptosis types, whereas satisfactory postoperative symmetry occurred in 60% of unilateral and 100% of bilateral congenital ptosis cases (last follow-up). Complications occurred in 10 eyelids (9%) and reoperation occurred in 10 eyelids (9%). CONCLUSION The use of silicone rod frontalis suspension surgery for ptosis repair in pediatric patients is modestly effective, with few complications and easy removal and adjustment.