Papilledema Outcomes from the Optical Coherence Tomography Substudy of the Idiopathic Intracranial Hypertension Treatment Trial.
AI Summary
Acetazolamide and weight loss effectively reduce papilledema-related optic nerve swelling in IIH patients, as measured by OCT, offering objective treatment monitoring for this condition.
Abstract
Purpose
To assess treatment efficacy using spectral-domain (SD) optical coherence tomography (OCT) measurements of papilledema in the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT), which evaluated the effects of acetazolamide and weight management and of placebo and weight management in eyes with mild visual loss.
Design
Randomized double-masked control clinical trial of acetazolamide plus weight management compared with placebo plus weight management in subjects with mild visual field loss and previously untreated idiopathic intracranial hypertension (IIH).
Participants
Eighty-nine (43 acetazolamide treated, 46 placebo treated) of 165 subjects meeting IIHTT entry criteria.
Methods
Subjects underwent perimetry, papilledema grading (Frisén method), high- and low-contrast visual acuity, and SD OCT imaging at study entry and 3 and 6 months. Study eye results (worse perimetric mean deviation [PMD]) were used for most analyses.
Main outcome measures
Retinal nerve fiber layer (RNFL) thickness, total retinal thickness (TRT), optic nerve (ONH) volume, and retinal ganglion cell layer (RGCL) measurements derived using 3-dimensional segmentation.
Results
Study entry OCT values were similar in both treatment groups. At 6 months, the acetazolamide group had greater reduction than the placebo group for RNFL thickness (175 μm vs. 89 μm; P = 0.001), TRT (220 μm vs. 113 μm; P = 0.001), and ONH volume (4.9 mm(3) vs. 2.1 mm(3); P = 0.001). The RNFL thickness (P = 0.01), TRT (P = 0.003), and ONH volume (P = 0.002) measurements also showed smaller increases in subjects who lost 6% or more of study entry weight. The acetazolamide (3.6 μm) and placebo (2.1 μm) groups showed minor RGCL thinning (P = 0.06). The RNFL thickness, TRT, and ONH volume measurements showed moderate correlations (r = 0.48-0.59; P ≤ 0.0001) with Frisén grade. The 14 eyes with RGCL thickness less than the fifth percentile of controls had worse PMD (P = 0.001) than study eyes with RGCL in the fifth percentile or more.
Conclusions
In IIH, acetazolamide and weight loss effectively improve RNFL thickness, TRT, and ONH volume swelling measurements resulting from papilledema. In contrast to the strong correlation at baseline, OCT measures at 6 months show only moderate correlations with papilledema grade.
MeSH Terms
Shields Classification
Key Concepts5
In the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT), the acetazolamide group showed a greater reduction in retinal nerve fiber layer (RNFL) thickness (175 μm) compared to the placebo group (89 μm) at 6 months (P = 0.001) in subjects with mild visual loss due to idiopathic intracranial hypertension.
In the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT), the acetazolamide group demonstrated a greater reduction in total retinal thickness (TRT) (220 μm) compared to the placebo group (113 μm) at 6 months (P = 0.001) in subjects with mild visual loss due to idiopathic intracranial hypertension.
In the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT), the acetazolamide group exhibited a greater reduction in optic nerve head (ONH) volume (4.9 mm^3) compared to the placebo group (2.1 mm^3) at 6 months (P = 0.001) in subjects with mild visual loss due to idiopathic intracranial hypertension.
In the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT), subjects who lost 6% or more of their study entry weight showed smaller increases in retinal nerve fiber layer (RNFL) thickness (P = 0.01), total retinal thickness (TRT) (P = 0.003), and optic nerve head (ONH) volume (P = 0.002) measurements, indicating improvement in papilledema.
In the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT), retinal nerve fiber layer (RNFL) thickness, total retinal thickness (TRT), and optic nerve head (ONH) volume measurements showed moderate correlations (r = 0.48-0.59; P ≤ 0.0001) with Frisén grade, a clinical papilledema grading method.
Related Articles5
Topical phenylephrine decreases blood velocity in the optic nerve head and increases resistive index in the retinal arteries.
Clinical TrialThe Effect of Treatment of Idiopathic Intracranial Hypertension on Prevalence of Retinal and Choroidal Folds.
Randomized Controlled TrialEffects of 0.5% apraclonidine on optic nerve head and peripapillary retinal blood flow.
Clinical TrialEffects of Dorzolamide on Retinal and Choroidal Blood Flow in the DBA/2J Mouse Model of Glaucoma.
Basic ScienceThe effect of glucagon-like peptide-1 agonists on ocular parameters in idiopathic intracranial hypertension patients: a retrospective study.
Cohort StudyIs this article assigned to the wrong chapter(s)? Let us know.