Late-recognized primary congenital glaucoma

Iris thickness and volume be measured using iris base instead of scleral spur as reference in anterior optical coherence tomography scan

PURPOSE:

To compare the iris parameters (iris thickness [IT] and volume) measured at different locations on iris determined using iris base (IB) and scleral spur (SS) in healthy Saudi eyes and factors affecting the differences.

METHODS:

Healthy eyes of Saudi persons were evaluated using anterior segment optical coherence tomography (AS-OCT). The IT was measured using Image J software and OCT scans in the horizontal axis in light on and light off condition. First IB was used as reference, and then, SS was used as reference for these measurements.

RESULTS:

One hundred healthy eye's AS-OCT scan was studied. The IT at the temporal side of the horizontal axis at 750 µ away from IB with lights on was 0.526 ± 0.08 µ, whereas it was 0.52 ± 0.08 µ from SS. The difference was significantly more in IB than SS method (P = 0.005). This difference if IT in SS and IB method was not affected by gender (Mann–Whitney P = 0.3), type of refractive error (K W P = 0.7), and level of illumination (K W P = 0.7).

CONCLUSION:

IT and IV measured using IB provided reliable data but overestimates compared to SS method. In the absence of SS visibility, IB could be alternative to assess iris parameters.

A Service Coverage Analysis of Primary Congenital Glaucoma Care Across the United States

PURPOSE

To assess the number of infants at risk of delayed primary congenital glaucoma (PCG) evaluation due to long travel times to specialists.

DESIGN

Cross-sectional geospatial service coverage analysis.

METHODS

All American Glaucoma Society (AGS) and American Association for Pediatric Ophthalmology and Strabismus (AAPOS) provider locations were geocoded using each organization's member directory. Sixty-minute drive time regions to providers were generated using ArcGIS Pro (Esri). The geographic intersection of AGS and AAPOS service areas was computed because patients typically require visits to both types of specialists. American Community Survey data were then overlaid to estimate the number of infants within and beyond the AGS/AAPOS service areas.

RESULTS

One thousand twenty-nine AGS and 1,040 AAPOS provider locations were geocoded. The analysis yielded 944,047 infants age 0-1 year (23.6%) who live beyond the AGS/AAPOS service areas. Therefore, approximately 14-94 new PCG cases/year may be at risk of delayed diagnosis as a result of living in a potential service desert. Compared with children living within the AGS/AAPOS service areas, children aged <6 years in these potential service deserts were more likely to live in households earning below the US federal poverty level, lack health insurance, and live in a single-parent home. These communities are disproportionately likely to experience other rural health disparities and are more prevalent across the Great Plains.

CONCLUSION

Service coverage analysis is a useful tool for identifying underserved regions for PCG referrals and evaluation. These data may assist in targeting screening programs in low access areas for pediatric glaucoma care.

Cyclodiode Laser as the First Surgical Approach in Childhood Glaucoma Under the Age of 8 Years

PRCIS

Cyclodiode as a primary treatment for childhood glaucoma patients younger than 8 years has a 12-month success rate of 55.24%. It can delay the need for penetrating glaucoma surgery.

PURPOSE

The purpose of this study was to evaluate the treatment outcome of cyclodiode laser in childhood glaucoma for patients under the age of 8 years.

DESIGN

This was a retrospective, consecutive, noncomparative case series.

PARTICIPANTS

All childhood glaucoma patients who underwent cyclodiode from March 2005 to January 2017 as a primary surgical treatment under the age of 8 years.

METHODS

A retrospective review of the medical records of consecutive patients who underwent cyclodiode by a single surgeon.

MAIN OUTCOME MEASURES

Success for single-diode intervention was defined as intraocular pressure (IOP) (>6 wk postoperative) ≤21 mm Hg with antiglaucoma medications and ≥20% IOP reduction, no further glaucoma surgery including cyclodiode, no loss of perception of light, and no major complications. Success for multiple-diode interventions was defined similar to the single diode, except that repeated cyclodiode is not considered a failure.

RESULTS

In all, 59 eyes of 43 patients were studied. The most common diagnosis was aphakic glaucoma. The mean age at cyclodiode treatment was 2.7 years (SD=2.2). Fifty-six percent of the patients were under 3 years. Success rates at 12 months after the procedure were 46.67% and 55.24% for single-diode and multiple-diode interventions, respectively. An IOP of >20 mm Hg 6 weeks after a cyclodiode session is a significant risk factor for failure with an hazard ratio of 2.41 (95% confidence interval: 1.00-5.81; P=0.05). Among the operated eyes, the surgeon could avoid further glaucoma surgery in 67.8% of the eyes during the first year after single or multiple cyclodiode sessions. None of the eyes experienced phthisis bulbi, hypotony, and severe uveitis.

CONCLUSIONS

Cyclodiode laser in childhood glaucoma patients under the age of 8 years can be considered a safe alternative for glaucoma patients who can have a high risk of surgical complications. Performing cyclodiode laser can delay the need for penetrating glaucoma surgery. The IOP at 6 weeks may be a good predictor for the treatment outcome.

Updates on the molecular genetics of primary congenital glaucoma (Review)

Primary congenital glaucoma (PCG) is one of the primary causes of blindness in children and is characterized by congenital trabecular meshwork and anterior chamber angle dysplasia. While being a rare condition, PCG severely impairs the quality of life of affected patients. However, the pathogenesis of PCG remains to be fully elucidated. It has previously been indicated that genetic factors serve a critical role in the pathogenesis of PCG, although patients with PCG exhibit significant genetic heterogeneity. Mutations in the cytochrome P450 family 1 subfamily B member 1 gene have been implicated in PCG and further genes that have been reported to be involved in PCG are myocilin, forkhead box C1, collagen type I α1 chain and latent transforming growth factor β binding protein 2. The present review aims to provide an up to date understanding of the genes associated with PCG and the use of molecular technologies in the identification of such genes and mutations. This may pave the way for the development of preventative methods, early diagnosis and improved therapeutic strategies in PCG.

Early Predictors of Long-term Outcomes in Childhood Glaucoma

PURPOSE

A data-based staging system for childhood glaucoma is likely to improve the prediction of visual acuity and intraocular pressure (IOP) control outcomes. We investigated early clinical factors associated with poor long-term visual, and IOP control outcomes in early-onset glaucoma as the initial steps to constructing a severity staging system.

DESIGN

Statistical modeling of retrospective case series data.

PARTICIPANTS

Glaucoma patients younger than 3 years of age who presented to Bascom Palmer Eye Institute between 1990 and 2010 with at least 5 years of follow up.

METHODS

Statistical modeling of retrospective case series data from first, second, third, 3-year, 5-year, and final visits.

MAIN OUTCOME MEASURES

Association of early clinical characteristics to final IOP-control outcomes and visual acuities.

RESULTS

A total of 26 eyes of 15 children were included. Nine of 15 (60%) of patients were male. Mean age at initial presentation: 9.98±10.55 months. Mean duration between initial and final visits: 11.13±3.55 years. By the third visit (mean 6.69 mo after presentation), presence of nystagmus, anterior segment dysgenesis (ASD) or having failed angle surgery increased the final LogMAR visual acuity by 0.76 (P=0.0516), 0.64 (P=0.0618), and 0.58 (P=0.0159), respectively. At year 3, failed amblyopia therapy, failed angle surgery, nystagmus, media opacity (MO), or ASD increased the final LogMAR by 1.30, 1.34, 1.21, 0.85, 0.64, respectively (all P<0.02). Failed angle surgery or MO increased the chance of uncontrolled IOP at the final visit (proportional odds ratio of 6.77 and 12.88, respectively).

CONCLUSIONS

In this pilot study of a modest size cohort, the presence of nystagmus, ASD or failed angle surgery early in the course of infantile-onset glaucoma management predicted poor final visual outcome, whereas failed angle surgery and presence of MO predicted poor final IOP control. These predictors of poor outcomes will serve as the initial steps in constructing a severity staging system.

Launching a paradigm for first and redo-surgery in primary congenital glaucoma: institutional experience

AIM

To evaluate the outcome of the initial and the redo-surgeries for primary congenital glaucoma (PCG) correlated to its degree of severity.

METHODS

A retrospective study involved patients with PCG presented between 2010 and 2018. Medical records were reviewed to assess the degree of the preoperative severity according to the intraocular pressure (IOP), corneal diameter and corneal edema. Success and failure rates were calculated for both first and redo-surgeries at 6 and 12mo respectively then correlated to the severity of the cases.

RESULTS

Complete records were retrieved for 272 eyes (153 patients) with PCG: 43 eyes were mild, 136 moderate and 93 severe. Combined trabeculotomy and trabeculectomy (CTT) had the highest success rate in moderate (96.4%) and severe cases (59.3%) while trabeculotomy had the highest success rate in mild cases (96.3%). Medical records of 88 eyes (63 patients) with recurrent PCG were analyzed, most with severe presentation (59 eyes). Ahmed glaucoma valve (AGV) was used in 67 (76%) eyes and augmented trabeculectomy in 21 (24%) eyes. At 12mo, there was no statistically significant difference between both surgeries in total success rate (P=0.256). For mild cases, success rate was 100% for both surgeries. Severe cases had higher success rates following AGV (87%) than augmented trabeculectomy (20%). Preoperative severity of the disease was an independent factor affecting the failure rate in secondary trabeculectomy but not in AGV. Patients younger than 24mo had higher probabilities of failure following both redo-surgeries with hazard ratio=1.325 and 0.37 for augmented trabeculectomy and AGV respectively.

CONCLUSION

Preoperative assessment of the severity of eyes with PCG helps in the selecting the optimal primary and secondary surgery. For first surgery, trabeculotomy is more effective in mild cases whereas; CTT and augmented subscleral trabeculectomy (SST) are appropriate for moderate and severe cases. AGV proved to be superior to augmented SST in severe recurrent cases.

Surgical Outcomes of Trabeculotomy in Newborns with Primary Congenital Glaucoma

Background:

Early surgical intervention is required for the primary congenital glaucoma (PCG). There are currently few reports on the surgical outcomes in infants with PCG. This study aimed to evaluate the efficacy and safety of trabeculotomy and the postoperative visual outcomes in Chinese newborns with PCG within 4 weeks of birth.

Methods:

A total of 21 eyes of 12 patients with PCG who underwent primary trabeculotomy within 4 weeks of birth were retrospectively studied. Preoperative and postoperative intraocular pressure (IOP), corneal clarity and diameter, axial length and optic disc cupping, visual acuity and postoperative refractive error, success rates, and complications were evaluated. Kaplan-Meier survival analysis was applied to evaluate the success rates.

Results:

The mean follow-up time was 46.9 ± 34.4 months (range: 12–122 months). The postoperative IOP was significantly lower than the preoperative IOP at all of the follow-up visits (P < 0.001). The complete success rates for all eyes at 1, 2, 3, and 5 years postoperatively were 90.5%, 85.7%, 85.7%, and 85.7%, respectively. The IOPs of the three patients who needed antiglaucomatous medications postoperatively were also well controlled. At the last visit, the cornea became clear, and the cup-to-disc ratio decreased significantly (P = 0.01) although the horizontal corneal diameter did not change significantly (P = 0.11). Visual acuities were able to be recorded in eight eyes at the last visit, among which six eyes had a best-corrected visual acuity of 20/40 or better. There were no severe intraoperative or postoperative complications.

Conclusions:

Trabeculotomy proves to be a safe and effective treatment in reducing IOP in this group of Chinese newborns with PCG. The outcomes of vision function were satisfactory in most of the patients.

Corneal Haze as Prognostic Indicator of Intraocular Pressure in Primary Congenital Glaucoma

PURPOSE

To perform a longitudinal analysis on the association of corneal haze with intraocular pressure (IOP) in eyes with primary congenital glaucoma (PCG) over 3 years.

PATIENTS AND METHODS

Charts of all patients diagnosed with glaucoma of childhood from 2002 to 2012 at our institution were retrospectively reviewed. Inclusion criteria were age 18 years and below, plus elevated IOP or characteristic clinical signs. Exclusion criteria were eyes with secondary glaucoma or corneal haze not from PCG and patients with prior ocular surgery or incomplete follow-up.

RESULTS

Of 79 eyes with childhood glaucoma during this period, 36 eyes had PCG [25 patients; 15 male (60.0%), 14 bilateral (56.0%)]. Eighteen eyes (13 patients) presented with corneal haze, whereas 18 eyes (12 patients) did not. Eyes with haze were diagnosed at a younger age than eyes without haze (0.79 vs. 5.2 y, P<0.02). During year 1, eyes with haze underwent significantly more IOP-lowering procedures and used significantly fewer IOP-lowering medications. Multivariate analysis revealed that corneal haze increased IOP by 4.63 mm Hg when controlling for treatment over time (P<0.01). Eyes with haze had lower survival curves and a failure hazard of 1.3 times that of eyes without haze. These eyes had a lower proportion of qualified successes than eyes without haze at year 1 (P<0.05) but this was reversed at year 3 (P<0.02).

CONCLUSIONS

Eyes with PCG-related corneal haze generally presented more severely than did those without haze, but postmanagement outcomes may be similar to those in eyes without haze.

Distribution of intraocular pressure and its determinants in an Iranian adult population

AIM

To determine the distribution of intraocular pressure (IOP) and its determinants in an Iranian population.

METHODS

In a cross-sectional survey, random cluster sampling was conducted from the 40-64 years old population of Shahroud, in the north of Iran. All participants had optometry and ophthalmic exams. IOP was determined using the Goldmann tonometry method and biometric components were measured.

RESULTS

Of the 6311 people selected for the study, 5190 (82.2%) participated. The mean age of the participants was 50.9±6.2y and 58.7% of them were female. Mean IOP was 12.87±2.27 mm Hg. In this study 0.3% of the participants had an IOP higher than 21 mm Hg. The multiple linear regression model revealed that sex (Coef=-0.30; 95% CI: -0.43 to -0.17), diabetes (Coef=0.43; 95% CI: 0.19 to 0.67), high systolic blood pressure (Coef=0.02; 95% CI: 0.01 to 0.02), high body mass index (BMI) (Coef=0.03; 95% CI: 0.01 to 0.04), higher education (Coef=0.02, 95% CI: 0.01 to 0.04), thicker central corneal thickness (Coef=0.01; 95% CI: 0.01 to 0.02), and myopic shift in spherical equivalent (Coef=-0.14; 95% CI: -0.18 to -0.10) significantly correlated with high IOP.

CONCLUSION

The IOP in this 40-64 years old population is low overall. In the north of Iran, average IOP is statistically significantly correlated with female sex, diabetes, higher BMI, systolic blood pressure, higher education, thicker cornea, and myopic refractive error.