Axenfeld-Rieger syndrome in the pediatric population: A review

Axenfeld-Rieger syndrome (ARS) is a rare autosomal-dominant neurocristopathy that presents with a variety of classical ocular and systemic findings. The pathophysiology of the disease involves anterior segment dysgenesis, and patients may present with ophthalmic complications early in life, including secondary glaucoma, high refractive errors, amblyopia, and permanent visual damage. There are a limited number of studies in the literature that focus primarily on pediatric patients with ARS. The purpose of this article was to review the current literature on clinical presentation, genetic associations, diagnosis, secondary complications, and treatment of ARS in pediatric patients. Evaluating the essential clinical aspects of the disease in children may allow for earlier diagnosis and treatment and prevent visual morbidity from amblyopia and secondary glaucoma that may result in permanent visual damage.

Twenty-Years of Experience in Childhood Glaucoma Surgery

To quantify the results of childhood glaucoma treatment over time in a cohort of children with different types of childhood glaucoma. A retrospective cohort study of consecutive cases involving children with primary congenital glaucoma, primary juvenile, and secondary juvenile glaucoma at the Childhood Glaucoma Center, University Medical Center Mainz, Germany from 1995 to 2015 was conducted. The main outcome measure was the long-term development of intraocular pressure. Further parameters such as surgical success, refraction, corneal diameter, axial length, and surgical procedure in children with different types of childhood glaucoma were evaluated. Surgical success was defined as IOP < 21 mmHg in eyes without a need for further intervention for pressure reduction. A total of 93 glaucomatous eyes of 61 childhood glaucoma patients with a mean age of 3.7 ± 5.1 years were included. The overall mean intraocular pressure at first visit was 32.8 ± 10.2 mmHg and decreased to 15.5 ± 7.3 mmHg at the last visit. In the median follow-up time of 78.2 months, 271 surgical interventions were performed (130 of these were cyclophotocoagulations). Many (61.9%) of the eyes that underwent surgery achieved complete surgical success without additional medication. Qualified surgical success (with or without additional medication) was reached by 84.5% of the eyes.

Surgical outcomes of Glaucoma associated with Axenfeld-Rieger syndrome

Background

The surgical management of glaucoma associated with Axenfeld-Rieger Syndrome (ARS) is poorly described in the literature. The goal of this study is to compare the effectiveness of various glaucoma surgeries on intraocular pressure (IOP) management in ARS.

Methods

Retrospective cohort study at a university hospital-based practice of patients diagnosed with ARS between 1973 and 2018. Exclusion criterion was follow-up less than 1 year. The number of eyes with glaucoma (IOP ≥ 21 mmHg with corneal edema, Haabs striae, optic nerve cupping or buphthalmos) requiring surgery was determined. The success and survival rates of goniotomy, trabeculotomy±trabeculectomy (no antifibrotics), cycloablation, trabeculectomy with anti-fibrotics, and glaucoma drainage device placement were assessed. Success was defined as IOP of 5-20 mmHg and no additional IOP-lowering surgery or visually devastating complications. Kaplan-Meier survival curves and the Wilcoxon test were used for statistical analysis.

Results

In 32 patients identified with ARS (median age at presentation 6.9 years, 0–58.7 years; median follow-up 5.4 years, 1.1–43.7 years), 23 (71.9%) patients were diagnosed with glaucoma at median age 6.3 years (0–57.9 years). In glaucomatous eyes (46 eyes), mean IOP at presentation was 21.8 ± 9.3 mmHg (median 20 mmHg, 4-45 mmHg) on 1.0 ± 1.6 glaucoma medications. Thirty-one eyes of 18 patients required glaucoma surgery with 2.2 ± 1.2 IOP-lowering surgeries per eye. Goniotomy (6 eyes) showed 43% success with 4.3 ± 3.9 years of IOP control. Trabeculotomy±trabeculectomy (6 eyes) had 17% success rate with 14.8 ± 12.7 years of IOP control. Trabeculectomy with anti-fibrotics (14 eyes) showed 57% success with 16.5 ± 13.5 years of IOP control. Ahmed© (FP7 or FP8) valve placement (8 eyes) had 25% success rate with 1.7 ± 1.9 years of IOP control. Baerveldt© (250 or 350) device placement (8 eyes) showed 70% success with 1.9 ± 2.3 years of IOP control. Cycloablation (4 eyes) had 33% success rate with 2.7 ± 3.5 years of IOP control. At final follow-up, mean IOP (12.6 ± 3.8 mmHg, median 11.8 mmHg, 7-19 mmHg) in glaucomatous eyes was significantly decreased (p < 0.0001), but there was no difference in number of glaucoma medications (1.6 ± 1.5, p = 0.1).

Conclusions

In our series, greater than 70% of patients with ARS have secondary glaucoma that often requires multiple surgeries. Trabeculectomy with anti-fibrotics and Baerveldt glaucoma drainage devices showed the greatest success in obtaining IOP control.

Prognostic factors of pediatric glaucoma: a retrospective study

PURPOSE

To correlate the features of certain types of infantile glaucoma with the progression and the prognosis of the disease, highlighting probable risk factors.

METHODS

Seventy-six patients with pediatric glaucoma were recruited in this retrospective study. All patients underwent ophthalmological examination in the Department of Ophthalmology of the Saarland University Medical Center from January 2001 to December 2012. Our pediatric patients were classified into four different categories of glaucoma: (1) primary congenital glaucoma (presenting buphthalmus), (2) aniridia-related glaucoma, (3) Peters/Rieger's anomaly-related glaucoma and (4) congenital cataract-related glaucoma. Personal data comprised age, sex, nationality, systemic diseases and gestational age. The best-corrected visual acuity (BCVA), the cup-disk ratio (CDR), the intraocular pressure (IOP), the corneal diameter and thickness, along with the Haab striae and corneal haze, were recorded.

RESULTS

The majority of the children were male (58%) and suffered from aniridia-related glaucoma (38%). Children with aniridia exhibited the worst BCVA. The CDR and IOP were significantly higher in children with primary congenital glaucoma, compared to the other groups, at the first visit. Those children also were with the largest corneal diameter and prevalence of Haab striae compared to the rest groups, whereas corneal haze was found more often and was more pronounced in children with Peters/Rieger's syndrome.

CONCLUSIONS

We concluded that glaucoma was earlier detected in children with primary congenital glaucoma, who exhibited increased corneal diameter and high percentage of Haab striae comparing to the other groups. However, these children responded successfully to any therapeutic intervention, exhibiting better BCVA and IOP values than the rest groups at the second visit.

Extrapolation of Efficacy in Pediatric Drug Development and Evidence-based Medicine: Progress and Lessons Learned

BACKGROUND

"Complete Extrapolation" of efficacy from adult or other pediatric data, to the pediatric population, is an important scientific tool that reduces the need for pediatric efficacy trials. Dose finding and safety studies in pediatrics are still needed. "No Extrapolation" requires 2 pediatric efficacy trials. "Partial Extrapolation" eliminates the need to conduct 2 pediatric efficacy trials; 1 efficacy or exposure/response study may be sufficient. We examined pediatric extrapolation from 2009 to 2014 evaluating any changes in extrapolation assumptions and the causes for these changes since a prior analysis published in 2011.

METHODS

We reviewed all 157 products with 388 pediatric studies submitted to the FDA from 2009 through 2014. We assessed whether efficacy was extrapolated from adult or other pediatric data and categorized extrapolation as Complete, Partial, or No, and identified the reasons for the changes.

RESULTS

Partial extrapolation decreased, whereas use of No and Complete extrapolation noticeably increased. Complete, Partial, or No extrapolations changed from 14%, 68%, and 18% in the 2011 study to 34%, 29%, and 37% respectively in the current study. The changes were mostly due to a better understanding of pediatric pathophysiology, why trials have failed, and improved endpoints.

CONCLUSIONS

Evolving science and data obtained from clinical trials increases the certainty of extrapolation assumptions and drives decisions to utilize extrapolation. Lessons learned from the conduct of these trials are critical to improving evidence-based medicine. Extrapolation of Efficacy is a powerful scientific tool that streamlines pediatric product development. Increased knowledge and evolving science inform utilization of this tool.

Cardiac safety of ophthalmic timolol

INTRODUCTION

It is generally believed that topical administration of eye drops safeguards against harmful systemic effects. However, about 80% of the drug in the ophthalmic products is systemically absorbed and the first-pass metabolism is avoided. Ophthalmic timolol is widely prescribed in the treatment of glaucoma either alone or in the combination eye drop products, many of which have been launched fairly recently. Ophthalmic timolol may cause serious adverse effects such as symptomatic bradycardia, various conduction disorders in the heart, orthostatic hypotension, syncope and falls. Areas covered: In this review we document a number of factors associated with the properties of ophthalmic timolol and specific features of a patient, which may jeopardize patient's cardiac safety even after topical treatment. Expert opinion: Plasma timolol levels are correlated with cardiovascular adverse effects in patients, since timolol is mainly metabolized by cytochrome P450 2D6 (CYP2D6) enzyme in the liver. Patients who are lacking the functional CYP2D6 or who are concomitantly using potent CYP2D6 inhibitor drugs (e.g. paroxetine or fluoxetine) or verapamil or other beta-blockers are at risk of getting serious cardiac adverse effects. Prior to treatment initiation, ECG should be always performed and CYP2D6 genotyping should be considered, if routinely available.

Pediatric Glaucoma: Pharmacotherapeutic Options

Childhood glaucoma is a major therapeutic challenge for pediatric ophthalmologists and glaucoma specialists worldwide. Management depends on the etiology and age at presentation. A variety of drugs are available for the control of intraocular pressure in children; however, none of these drugs have been licensed by the regulatory agencies for use in children. Furthermore, evidence gained from randomized controlled trials in the pediatric population is sparse, and little is known regarding the use of newer anti-glaucoma preparations. This evidence-based review aims to discuss the available pharmacotherapeutic options for glaucoma in children. Topical adrenoceptor blockers, topical and systemic carbonic anhydrase inhibitors, prostaglandin (PG) analogs, adrenoceptor agonists, parasympathomimetics, and combined preparations are available for use in children, but usually as an off-label indication. Therefore, it is important to recognize that serious side effects have been reported, even with topical drops, and measures to reduce systemic absorption should be taken. Most drugs have been shown to have comparable ocular hypotensive effects, with the lowest occurrence of systemic side effects with PG analogs. Whereas a newly introduced prostaglandin analog, tafluprost, and some other preservative-free preparations have shown promising results in adult glaucoma patients, no pediatric reports are available as yet. Future studies may describe their role in treating pediatric glaucoma. This review also shares some suggested treatment pathways for primary congenital glaucoma (PCG), juvenile open angle glaucoma (JOAG), developmental glaucoma, aphakic/pseudophakic glaucoma, and uveitic glaucoma.

Primary congenital glaucoma outcomes: lessons from 23 years of follow-up

PURPOSE

To determine in primary congenital glaucoma whether age of presentation influences surgical success, the degrees of angle surgery needed to achieve glaucoma control, and whether there are critical ages where glaucoma progresses, requiring further surgical management.

DESIGN

Retrospective cohort study.

METHODS

The medical records of patients with primary congenital glaucoma over a 23-year period were reviewed: 192 procedures were performed on 117 eyes (70 patients). The number and age of angle procedures and final visual acuity was analyzed. Surgical success was defined as stable intraocular pressure and optic disc appearance.

RESULTS

Procedures involving 83 of the 110 eyes (75.5%) undergoing angle surgery were successful, with 2-, 4-, 6-, and 10-year success rates of 92%, 86%, 84%, and 75%, respectively. Subgroup analysis (<3 months; 3-6 months; >6 months) comparing age of diagnosis to visual outcome (<20/200, 20/200-20/40, >20/40) was significant (P = .04). The age at first operation (P = .94), the number of angle operations (P = .43), and their effect on angle surgery success was not significant. Seven of 192 operations were performed after the age of 8 years (3.6%). After the initial angle surgeries within the first year of life, the third procedure occurred at a median age of 2.4 years (interquartile ratio [IQR] 0.6-3.8 years) and the fourth procedure occurred at a median age of 5.3 years (IQR 2.5-6.1 years).

CONCLUSIONS

Children diagnosed at <3 months of age had a visual outcome of <20/200 despite successful glaucoma control. Age of presentation did not affect surgical success. A total of 78.9% of cases undergoing primary trabeculotomy were controlled with 1 operation: 4 clock hours of angle (120 degrees). Analysis of glaucoma progression suggests critical ages where further glaucoma surgery is required at around 2 and 5 years of age.

Late-recognized primary congenital glaucoma

PURPOSE

To describe a cohort of children with late-recognized primary congenital glaucoma (LRPCG), including age of presentation, age-related diagnostic signs, clinical abnormalities, and results of glaucoma surgery.

METHODS

The medical records of 31 patients (49 eyes) with PCG recognized after 1 year of age were reviewed retrospectively. Patients were confirmed to have PCG based on their increased intraocular pressure (IOP), anterior segment abnormalities including findings on gonioscopy, and the absence of other causes of childhood glaucoma. The outcome of glaucoma surgery was reviewed and success measured by assessment of the relative control of IOP, occurrence of significant complications, and need for additional glaucoma surgery.

RESULTS

Average age at diagnosis of glaucoma was 4.7 years (36% diagnosed at > 4 years of age). The most common initial diagnostic signs were corneal enlargement (46%, average age of 2.0 years), photophobia (20%, average age of 3.3 years), and suspected poor visual acuity (32%, average age of 9.9 years). Corneal cloudiness was not an initial sign for any patient. Haab's striae were present in 60% of the affected 49 eyes. Gonioscopy findings were abnormal in 82%, but the ciliary body band was seen in 81% and the scleral spur was visible in 47%. Sixty-one goniotomy procedures were performed for 39 eyes with overall success in 95% (37 eyes) and complete success in 65% (27 eyes). The final visual acuity was 20/200 or worse in 31% (15 eyes) and 20/40 or better in 60% (29 eyes).

CONCLUSIONS

An awareness of and familiarity with the subtle diagnostic signs of LRPCG can enable its differentiation from primary juvenile glaucoma and contribute to earlier recognition and treatment. Glaucoma surgery is often required for LRPCG and goniosurgery is the recommended initial procedure.

Hypertensive retinopathy in severely hypertensive children: demographic, clinical, and ophthalmoscopic findings from a 30-year British cohort

PURPOSE

There is scarce data regarding the incidence and clinical features of hypertensive retinopathy in children. The authors studied a large British cohort of severely hypertensive children to ascertain who developed hypertensive retinopathy, the severity, and the visual prognosis.

METHODS

A retrospective review was performed of children undergoing renal angiography for investigation of severe hypertension at a tertiary institution from 1980 to 2010. All relevant cardiovascular, radiologic, and ophthalmic information was collected from case notes of the children identified in the study period. The outcome measures were presenting blood pressure, presence/severity of hypertensive retinopathy, and visual outcome.

RESULTS

Fifty-three severely hypertensive children were identified; 30 with renovascular disease (RVD+) and 23 without (RVD-). The majority had 'stage 2 hypertension.' There were no significant differences in age, gender, or blood pressure between RVD+ and RVD- children. Seven (18%) of the 39 children receiving ophthalmic assessment had hypertensive retinopathy, of whom 6 had severe disease (retinal hemorrhages, exudates, and optic disc edema). There was a trend toward a higher prevalence of hypertensive retinopathy in the RVD+ group (n = 5) but this was not statistically significant. Children with hypertensive retinopathy had higher blood pressure than those without (median: 216/158 vs 150/98 mm Hg, P < .001).

CONCLUSIONS

This is the first study examining the incidence and characteristics of hypertensive retinopathy in British children with severe hypertension. The authors found an 18% incidence of hypertensive retinopathy, in some cases with permanent visual reduction.

Visual acuity outcomes in pediatric glaucomas

PURPOSE

To evaluate and compare the visual acuity prognosis in the various pediatric glaucoma subtypes and to determine risk factors for vision loss.

METHODS

The medical records of pediatric glaucoma patients from 2000 to 2010 at Children's Hospital of Philadelphia were retrospectively reviewed. Visual acuities, surgeries, glaucoma subtype, and etiology of vision impairment were recorded. Univariate and multivariate analyses were performed to determine the risk factors for visual impairment.

RESULTS

A total of 133 eyes (36.8% primary congenital glaucoma, 28.6% aphakic glaucoma, 12.0% glaucoma associated with anterior segment dysgenesis, 12.0% Sturge-Weber glaucoma) of 88 patients were included. At last follow-up (median length, 5 years), 46.6% eyes achieved excellent (≥20/70) visual acuity. Of the glaucoma subtypes, primary congenital glaucoma conferred the best visual prognosis, with 69.4% eyes with excellent (≥20/70) visual acuity at final follow-up. Factors most associated with visual impairment (<20/200) were unilateral disease, multiple surgeries, poor vision at diagnosis, and other ocular comorbidities. The most common primary etiology for vision impairment was amblyopia (54.9%).

CONCLUSIONS

Patients with glaucoma early in life appear to have a better visual acuity prognosis than previously reported, with those with primary congenital glaucoma faring better than other glaucoma subtypes. Recognition of risk factors for visual impairment can better guide clinical management and counseling of patients.

Glaucoma

Most medical practitioners have regular contact with adults who have one of the two forms of glaucoma: open-angle glaucoma or angle-closure glaucoma. Data from population-based surveys indicate that one in 40 adults older than 40 years has glaucoma with loss of visual function, which equates to 60 million people worldwide being affected and 8·4 million being bilaterally blind. Even in developed countries, half of glaucoma cases are undiagnosed. Glaucoma is mostly asymptomatic until late in the disease when visual problems arise. Vision loss from glaucoma cannot be recovered, and improved case-detection methods for glaucoma are needed. Glaucoma is commonly treated with daily eye-drop drugs, but adherence to treatment is often unsatisfactory. As a usually asymptomatic and chronic disease, glaucoma has similar treatment challenges to chronic systemic diseases. Similarities to the pathogenesis of common CNS diseases mean that common neuroprotective strategies might exist. Successful gene therapy, which has been used for other eye diseases might be possible for the treatment of glaucoma in the future.

Incidence and clinical characteristics of childhood glaucoma: a population-based study

OBJECTIVE

To describe the incidence and clinical characteristics of childhood glaucoma in a defined population of the United States.

METHODS

The medical records of all pediatric patients younger than 20 years living in Olmstead County, Minnesota, from January 1, 1965, through December 31, 2004, who met diagnostic criteria for glaucoma or glaucoma suspect were reviewed.

RESULTS

Thirty children were diagnosed as having glaucoma during the 40-year study period. The incidence of childhood glaucoma was 2.29 (95% confidence interval, 1.47-3.12) per 100,000 residents younger than 20 years, with the following types and incidences: 19 acquired (1.46/100,000; 0.80-2.12), 6 secondary (0.45/100,000; 0.08-0.82), and 5 primary glaucoma (0.38/100,000; 0.05-0.72). The birth prevalence of primary congenital glaucoma during the 40-year period was 1 per 68 254 residents younger than 20 years or 1.46 per 100,000 (95% confidence interval, 0.03-8.16). Twenty-four individuals with glaucoma suspect were also identified, yielding an incidence of 1.9 per 100,000 residents younger than 20 years (95% confidence interval, 1.14-2.66).

CONCLUSION

The incidence of childhood glaucoma in this population was 2.29 per 100,000 residents younger than 20 years or 1 per 43 575 residents younger than 20 years. Acquired and secondary forms of glaucoma were the most common, whereas congenital and juvenile glaucoma were rare.

Latanoprost in pediatric glaucoma--pediatric exposure over a decade

BACKGROUND

Although numerous studies of latanoprost in adult glaucoma have shown it to be an effective hypotensive agent with a low incidence of side effects, these issues have not been well studied in pediatric glaucomas. The purpose of the current study is to evaluate the safety and intraocular pressure (IOP) lowering effect of latanoprost in various pediatric glaucomas over a long period.

SUBJECTS AND METHODS

This retrospective study included all children treated with latanoprost at our institution from 1996 to 2007. Demographic, glaucoma-related, and side-effect information was recorded for each subject. Duration of latanoprost exposure was calculated in child-months (1 child exposed for 1 month). If interpretable IOP data were available, the presence or absence of a treatment response (IOP reduction > or =15% from baseline) was determined for each subject.

RESULTS

A total of 115 subjects with latanoprost exposure were identified, with a collective exposure of 2,325 child-months. Exposure for > or =1 year occurred in 52 subjects. Side effects were mild and infrequently reported. Of the 115 subjects, 63 had interpretable IOP data, and 22 (35%) were treatment responders. Predictors of a response included a diagnosis of juvenile open-angle glaucoma, monotherapy, and older age.

CONCLUSIONS

This large study of latanoprost-treated children confirms the excellent safety profile of the drug in the treatment of pediatric glaucoma. The study also confirms latanoprost's IOP-lowering ability in older children with juvenile open-angle glaucoma and in some children with aphakic glaucoma. Prospective studies are needed to better define the optimal role of latanoprost in the treatment of pediatric glaucoma, especially congenital glaucoma.