Abstract
Purpose :
To assess the relationship between quantifiable proxy measures of ICP and VFL in paediatric IIH, and to characterise the change in VFL over IIH treatment course.
Methods :
A retrospective review of case notes of 60 eyes of 37 paediatric IIH patients with reliable (fixation losses<20% or false positives<33% or false negatives<33%) Humphrey Field Tests (HFT) was conducted. Analysis included: visual field index (VFI), MD (mean deviation) and PSD (pattern standard deviation) values; cerebrospinal fluid (CSF) infusion study or tap opening pressure, Optical Coherence Tomography (OCT) retinal nerve fibre layer (RNFL) thickness and papilloedema Frisén grading at presentation. Reliable HFT results available for 26 patients at the end of IIH treatment were evaluated for changes.
Results :
The 37 patients reviewed had a mean age of 13.3±2.2, were in the ratio male:female of 11:26, had a mean BMI of 26.9 and 73% were of White British ethnicity. Frisén grading was available for 42 eyes; mean grade 2.4. OCT mean RNFL thickness was available for 57 eyes; mean 194.3μm. CSF opening pressure was available for 46 eyes of 28 patients; mean opening pressure 25mmHg. Weak but statistically significant correlation was found between Frisén Grade and each of VFI, MD and PSD (r=-0.4773, -0.5025 and 0.3953, p<0.01), between RNFL thickness and each of VFI, MD and PSD (r=-0.3803, -0.4126 and 0.3774, p<0.01) and between CSF opening pressure and each of VFI, MD and PSD (r=-0.3986, -0.3985 and 0.3943, p<0.01). Mean VFI, MD and PSD at presentation were 95.2±7.29, -3.05±2.74 and 2.58±1.76 respectively, and showed no significant change after treatment lasting between 3.1–112.4 months.
Conclusions :
Statistically significant, fair correlations exist between Frisén grade, RNFL thickness or CSF opening pressure and reliably-measured VFI, MD and PSD in children with IIH. This suggests the extent of ICP as measured by degree of papilloedema on slit lamp examination, OCT or CSF manometry is predictive of the extent of VFL, and vice versa: the extent of VFL is predictive of ICP. VFI, MD, and PSD were generally found to be high at presentation and conserved over time. Further subgroup analysis, stratifying cases by papilloedema and VFL severity at presentation, will elucidate the relative importance of prompt intervention to prevent lasting VFL.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.