Visual photosensitivity threshold and objective photosensitivity luminance in healthy human eyes assessed using an automated ocular photosensitivity analyser: a step towards translation of a clinical tool for assessing photophobia

PURPOSE

To evaluate the visual photosensitivity threshold and objective photosensitivity luminance in healthy eyes, thereby providing a normative dataset that will lead to a better understanding of diseases causing photophobia.

METHODS

This was a prospective cross-sectional study. Emmetropes whose visual acuity was better than 0.18 logMAR (6/9) with no other ocular abnormality were included. Headache Impact Test-6 and visual light sensitivity questionnaires were administered. Visual photosensitivity threshold was measured subjectively using the ocular photosensitivity analyser. Objective photosensitivity luminance was assessed manually by evaluating videos recorded using an infrared camera and noting the intensity of light at the first squeezing reflex.

RESULTS

Seventy five normal subjects (age range, 7-71 years) were included. Median age was 32.7 years (inter-quartile range, 20.3-47.9 years). Forty (53.3%) were males. Median Headache Impact Test score was 38 (inter-quartile range, 36-42) and visual light sensitivity questionnaire score was 11 (inter-quartile range, 8-15). Mean (standard deviation) right eye, left eye and binocular visual photosensitivity threshold was 3.34 (0.78), 3.33 (0.81) and 3.37 (0.78) loglux, respectively. There was a significant negative correlation of visual light sensitivity questionnaire scores with right eye, left eye and binocular visual photosensitivity thresholds, and positive correlation of age with binocular visual photosensitivity thresholds. Mean (standard deviation) right eye, left eye and binocular objective photosensitivity luminance was 3.25 (0.55), 3.35 (0.47) and 3.15 (0.52) loglux, respectively. Age was only positively correlated with binocular objective photosensitivity luminance, and there was no correlation between age and right eye or left eye objective photosensitivity luminance.

CONCLUSIONS

The study characterised, for the first time, objective photosensitivity luminance and established normative data for both visual photosensitivity threshold and objective photosensitivity luminance. The data will help in understanding the pathophysiology of diseases causing photophobia, monitoring the disease progression and evaluating treatment modalities.

Outcomes of keratoplasty in a cohort of Indian patients with xeroderma pigmentosum

Purpose:

To evaluate the outcomes of keratoplasty for xeroderma pigmentosum (XP) performed at a tertiary eye care center.

Methods:

A retrospective review of medical records of those patients who were clinically diagnosed to have XP (54 eyes of 36 patients) and underwent keratoplasty; either deep anterior lamellar keratoplasty (DALK, four eyes), endothelial keratoplasty (EK, eight eyes), or penetrating keratoplasty (PK, 42 eyes) from 1994 to 2018.

Results:

The median age at surgery was 20.6 years (interquartile range [IQR], 14.6–27.6 years) and 20 (55.6%) were males. Graft failure occurred in 15 eyes (35.7%) in the PK group and two eyes (50%) in the DALK group; none failed in the EK group. The probability of graft survival in the PK group was 97.2% ± 2.7% at 1 year, 74.0% ± 8.0% at 2 years, and 54.8% ± 11.7% at 5 years. In the PK group, 13 eyes needed antiglaucoma medications, 11 eyes developed graft infiltrate, and 13 eyes needed secondary interventions (cataract surgery, excision biopsy, and tarsorrhaphy). In the EK group, three eyes needed secondary interventions (excision biopsy). Median postoperative endothelial cell density at the last follow-up in the PK group was 1214 cells/mm² (IQR, 623–2277 cells/mm²).

Conclusion:

Despite the complexities of the ocular surface and adnexal issues in XP, keratoplasty had reasonably good outcomes. More than half of the PK grafts survived 5 years with no failures in the EK group. Regular follow-up and timely management of suture-related infections raised intraocular pressure, and suspicious ocular surface lesions, in addition to solar protection, are important for the success of keratoplasty in these eyes.

Corneal endothelium in unilateral Fuchs heterochromic iridocyclitis

Purpose:

To assess the corneal endothelium in patients with Fuchs heterochromic iridocyclitis (FHI) and compare it with the normal fellow eye.

Methods:

Retrospective, observational, cross-sectional study of 31 patients seen between Jan 2016 to Dec 2018, with clinical diagnosis of Fuchs heterochromic iridocyclitis, was performed. Specular microscopic examination was documented in both eyes. The affected eyes formed the study group and the fellow healthy eyes served as controls.

Results:

The mean age of the patients was 29.9 ± 8.2 years. The endothelial cell density (P = 0.0001) was significantly lower, whereas average cell size (P = 0.0001), coefficient of variation (P = 0.004), and maximum cell area (P = 0.01) were significantly higher in the affected eye compared to the control eye. In three patients, the affected eye showed guttae, while the healthy fellow eye revealed a normal specular mosaic.

Conclusion:

Specular microscopic analysis shows endothelial alterations in the affected eyes in FHI.

Comparison of Visual Field Progression Rates Among the High Tension Glaucoma, Primary Angle Closure Glaucoma, and Normal Tension Glaucoma

Purpose

To compare the visual field (VF) progression among high tension glaucoma (HTG), primary angle closure glaucoma (PACG), and normal tension glaucoma (NTG) subjects in routine clinical care.

Methods

All patients had ≥5 VF tests using HFA, 24-2, SITA-standard strategy. We compared the progression between glaucoma subtypes after matching the VFs for baseline severity (mean deviation [MD]) and the age at presentation. Global VF progression was evaluated by linear regression analysis (LRA) of MD. For local VF progression, scotoma expansion (SE) defined as appearance of new scotoma and scotoma deepening (SD) defined by pointwise LRA were calculated. SE and SD were analyzed in three VF zones: superior arcuate (SA), inferior arcuate (IA), and central (C).

Results

A total of 310 HTG, 304 PACG, and 165 NTG eyes were included. When VFs were matched by baseline MD, a greater number (n = 20/76) of eyes with HTG showed significant progression compared to PACG (n = 9/76; P = 0.04). The number of progressing eyes were not significantly different between HTG and NTG (n = 11/76; P = 0.10) and between NTG and PACG (P = 0.65). When the baseline VFs were matched by age, the number of eyes showing significant progression were similar in all the subtypes. SA zone in HTG and NTG showed greater SE and SD compared to other zones (P < 0.05), whereas IA zone in PACG showed greater SE and SD compared to other zones (P < 0.05).

Conclusions

In our cohort of treated primary glaucoma with matched baseline severity, a greater proportion of HTG eyes progressed faster compared to PACG. SA zone in HTG and NTG and IA zone in PACG showed greater VF progression.