Does the World Health Organization criterion adequately define glaucoma blindness?

P Mokhles, JSAG Schouten, HJM Beckers, CAB Webers University Eye Clinic Maastricht, Maastricht, the Netherlands Purpose: Blindness in glaucoma is difficult to assess with merely the use of the current World Health Organization (WHO) definition (a visual field restricted to 10° in a radius around central fixation), as this criterion does not cover other types of visual field loss that are encountered in clinical practice and also depict blindness. In this study, a 5-point ordinal scale was developed for the assessment of common visual field defect patterns, with the purpose of comparing blindness as outcome to the findings with the WHO criterion when applied to the same visual fields. The scores with the two methods were compared between two ophthalmologists. In addition, the variability between these assessors in assessing the different visual field types was determined.Methods: Two glaucoma specialists randomly assessed a sample of 423 visual fields from 77 glaucoma patients, stripped of all indices and masked for all patient variables. They applied the WHO criterion and a 5-point ordinal scale to all visual fields for the probability of blindness.Results: The WHO criterion was mostly found applicable and in good agreement for both assessors to visual fields depicting central island of vision or a temporal crescent. The percentage of blindness scores was higher when using the ordinal scale, 21.7% and 19.6% for assessors A and B, respectively, versus 14.4% and 11.3% for the WHO criterion. However, Kappa was lower, 0.71 versus 0.78 for WHO.Conclusions: The WHO criterion is strictly applied and shows good agreement between assessors; however, blindness does not always fit this criterion. More visual fields are labeled as blind when a less stringent criterion is used, but this leads to more interobserver variability. A new criterion that describes the extent, location, and depth of visual field defects together with their consequence for the patient’s quality of life is needed for the classification of glaucoma blindness. Keywords: glaucoma, blindness, visual fields, World Health Organization&nbsp

Substance P and opioid peptidergic innervation of the anterior eye segment of the rat: an immunohistochemical study

Recently discovered endogenous opioid peptides such as nociceptin are known to modulate neurotransmitter release of primary afferent neurons (especially substance P, SP) and they have also been demonstrated in peripheral nerve fibres. The aim of this study was to investigate the opioid peptidergic innervation of the anterior eye segment and to compare it with the innervation pattern of SP in order to shed light on the functional relationship between these peptides. Anterior eye segments of 20 rat eyes were cut in a tangential plane and the sections stained with antibodies against SP, nociceptin, nocistatin, endomorphin 1 and 2, leu-enkephalin and met-enkephalin. Sections of the spinal cord or brain were used as positive controls. Numerous SP-immunoreactive nerve fibres were found in the conjunctiva, cornea, episclera, trabecular meshwork, iris and ciliary body. A weak staining for met-enkephalin and leu-enkephalin could only be found in the iris and anteriormost ciliary body. Nerve fibres immunoreactive for nociceptin, nocistatin, and endomorphin 1 or 2 could not be detected in any part of the anterior eye segment. It is tempting to speculate that the opioid peptidergic innervation of the anterior ciliary body may play a role in the modulation of intraocular inflammation

Referral for first glaucoma surgery in Europe, the ReF-GS study

PURPOSE: To analyze the appropriateness of referrals for incisional glaucoma-surgery in Europe. METHODS: Referrals for the first open-angle glaucoma surgery between January and October 2017 were analyzed in 18 countries: 8 "old" European Union, 7 "new" European Union and 3 non-European Union European countries. RESULTS: Most eyes had primary open-angle or exfoliative glaucoma. The average mean deviation was -13.8 dB with split fixation in 44.3%. No structural progression analysis was made before the referrals. The most common medications were the combination of a prostaglandin analog, timolol and a carbonic anhydrase inhibitor (30.0%), and all other combinations comprising ⩾ 3 molecules (33.8%). Laser trabeculoplasty was reported in only 18.4%. Of the 294 referrals, 41.5% were appropriate and timely, 35.0% appropriate but later than optimal, and 17.6% appropriate but too late (minimal vision maintained). The treatment period was significantly longer (median: 7 years) in the "old" European Union countries than in the other groups (3 and 2 years, respectively). No between-group differences were seen in intraocular pressure and mean deviation, but the non-European Union group referred the patients at significantly lower cup/disk ratio and eye drop usage than the other groups. Split fixation was significantly more common in the "old" (60.6%) than the "new" European Union countries (38.7%), and in both EU country-groups than in the non-European Union countries (13.6%). CONCLUSIONS: Of 294 European open-angle glaucoma referrals for first glaucoma-surgery, 41.5% were completely satisfactory. The damage was typically advanced, and the care varied considerably among the countries. This suggests that further efforts are necessary to improve glaucoma care in Europe.status: publishe