Risk Factors for the Structural Progression of Myopic Glaucomatous Eyes with a History of Laser Refractive Surgery

As laser refractive surgeries (LRS) have been widely performed to correct myopia, ophthalmologists easily encounter patients with glaucoma who have a history of LRS. It is well known that intraocular pressure (IOP) in eyes with glaucoma is not accurate when measured using Goldmann applanation tonometry. However, risk factors for glaucoma progression, particularly those associated with measured IOP, have rarely been studied. We analysed data for 40 patients with a history of LRS and 50 age-matched patients without a history of LRS. Structural progression was defined as significant changes in thickness in the peripapillary retinal nerve fibre layer as identified using optical coherence tomography event-based guided progression analysis. Risk factors were determined via Cox regression analysis. Disc haemorrhage (DH) was associated with glaucoma progression in both the non-LRS group and LRS group (hazard ratio (HR): 4.650, p = 0.012 and HR: 8.666, p = 0.019, respectively). However, IOP fluctuation was associated with glaucoma progression only in the LRS group (HR: 1.452, p = 0.023). Our results show that DH was a significant sign of progression in myopic glaucoma eyes. When treating patients with myopia and glaucoma, IOP fluctuation should be monitored more carefully, even if IOP seems to be well controlled.

Glaucoma conversion of the contralateral eye in unilateral normal-tension glaucoma patients: a 5-year follow-up study

Background/AimsTo investigate clinical characteristics and risk factors for glaucoma conversion of the contralateral eye in unilateral normal-tension glaucoma (NTG) patients.MethodsA retrospective observational cohort study was conducted on a total of 76 subjects who had been diagnosed with unilateral NTG at the baseline and followed up for more than 5 years. Glaucoma conversion in the contralateral eye was defined as increased thinning of neuro-retinal rim, development of retinal nerve fibre layer defect and/or development of glaucomatous visual field defect.ResultsDuring the mean follow-up period of 7.3±2.4 years, 21 of 79 (26.6%) subjects were confirmed to have developed glaucoma in the non-glaucomatous contralateral eye. The 5-year rate of glaucoma conversion in contralateral eyes was 19.7%. The maximum width of β-zone parapapillary atrophy (MWβPPA)-disc diameter (DD) ratio at the baseline and the presence rate of disc haemorrhage during follow-up period were significantly greater in the contralateral eyes of the conversion group than in those of the non-conversion group (p=0.011, <0.001, respectively). A multivariate Cox-proportional hazard model revealed intraocular pressure (IOP) over 17 mm Hg (HR 5.05, p=0.031), central corneal thickness (CCT) under 491 μm (HR 4.25, p=0.025) and MWβPPA-DD ratio over 0.32 (HR 6.25, p=0.003) in contralateral eye at the baseline as the independent risk factors for glaucoma conversion.ConclusionsAmong unilateral NTG patients, those with low CCT and high MWβPPA-DD ratio as well as high IOP in the contralateral eye are more likely to develop glaucoma in that eye during long-term follow-up.

Progressive retinal nerve fibre layer thinning and choroidal microvasculature dropout at the location of disc haemorrhage in glaucoma

Background/AimsTo investigate whether parapapillary choroidal microvasculature dropout (MvD) is associated with progressive retinal nerve fibre layer (RNFL) thinning in eyes with primary open-angle glaucoma (POAG) and disc haemorrhage (DH).MethodsParapapillary microvasculature was evaluated by swept-source optical coherence tomography (OCT) angiography (OCTA) in 50 eyes with POAG and DH, 1 year before, at the time of and 1 year after the detection of DH. MvD was defined as an area in the parapapillary deep layer of focal sectoral dropout with no visible microvascular network. Progressive changes in OCT RNFL thickness were compared in groups of eyes with and without MvD.ResultsCumulative prevalence of MvD was 76.0% (38 eyes) at 1 year after detection of DH. All MvDs were detected in the same sectoral locations as DH. In eyes with MvD, global RNFL thickness and sectoral RNFL thickness at the location of DH were significantly reduced, both from 1 year before to the time of DH detection (both p<0.001) and from DH detection to 1 year later (both p<0.001). In eyes without MvD, however, the reductions in global (p=0.011) and sectoral (p=0.007) RNFL thickness were significant only from DH detection to 1 year later.ConclusionIn eyes with POAG, RNFL thinning was spatially consistent and progressive at the location of MvD accompanied by subsequent DH and continued to progress after the occurrence of DH. When DH was not accompanied by MvD, progressive RNFL thinning was more likely to occur after the detection of DH.

Optic disc haemorrhage and primary open-angle glaucoma: a clinical review

Studies have confirmed that optic disc haemorrhage (ODH) is a significant risk factor for the development and progression of primary open-angle glaucoma (POAG). Various populations have differing risk factors for developing POAG. As such, a literature review was conducted examining seven studies published in India, China, Japan, Australia, Korea and the USA. The goal of this review was to better identify ODH risk factors and their relationship to development and progression of POAG. Ultimately, patients with ODH have a greater risk for developing POAG across all populations analysed in this review. However, some populations demonstrated additional risk factors for ODH, such as increasing age and female gender. Paradoxically, data from several studies show that people of African descent have a reduced risk of ODH despite having increased risk of open-angle glaucoma than their Caucasian counterparts. By parsing out the complex relations between ODH and open-angle glaucoma stratified by age, gender and race, we may gain a broader understanding of glaucoma pathogenesis and derive individualised treatment strategies.

Rate of three-dimensional neuroretinal rim thinning in glaucomatous eyes with optic disc haemorrhage

BackgroundTo investigate the thinning rate of three-dimensional neuroretinal rim thickness (3D-NRT) in glaucoma eyes with optic disc haemorrhage (DH) and its relationship to retinal nerve fibre layer thickness (RNFLT) progression.MethodsNinety-five (95) eyes of 95 glaucoma patients with initial DH in the inferotemporal (n=69) and superotemporal (n=26) regions and 48 eyes of 48 glaucoma patients without DH were retrospectively reviewed. The rates of change for 3D-NRT and RNFLT were compared by linear mixed-effect model. For the direct comparison between 3D-NRT and RNFLT, dynamic-range-based normalised coefficient was used. The effect of DH frequency on the rates of thinning of 3D-NRT and RNFLT was evaluated.ResultsDuring a mean 7-year follow-up, the rates of thinning of 3D-NRT (–5.69±4.88 µm/year) and RNFLT (–2.03±2.03 µm/year) at 7 o’clock were faster than those at other locations (all p<0.05) in DH eyes. The dynamic-range-based normalised rate of thinning was significantly faster for RNFLT (–2.06%±1.62%/year) than for 3D-NRT (–1.15%±1.10%/year, p<0.001) in DH eyes, but not in non-DH eyes (p=0.43). DH frequency in the inferotemporal region was associated with the thinning rate of 3D-NRT as well as RNFLT.ConclusionDH eyes are associated with the progression of both 3D-NRT and RNFLT, especially in the inferotemporal region. DH eyes show a relatively faster thinning rate of average RNFLT than 3D-NRT. The frequency of DH can affect the progression of 3D-NRT as well as RNFLT.

Association between focal lamina cribrosa defects and optic disc haemorrhage in glaucoma

Background/aimsTo explore the relationship between focal lamina defect (LD) size and optic disc haemorrhages (DH) in glaucomatous eyes.MethodsRadial B-scan images at 15° intervals obtained using enhanced depth imaging (EDI) spectral-domain optical coherence tomography (OCT) were performed on a group of subjects previously assessed for DH every 3 months over a period of 5 years. EDI-OCT scans were assessed for the presence of focal lamina cribrosa defects by a single observer.Results119 eyes from 62 subjects (44 females, 18 males) were analysed. 44 eyes (37%) were noted to have at least 1 LD, and of those, eight eyes had more than one defect. 68 eyes (57%) were observed to have at least one DH occur over the course of monitoring. 48 eyes (40%) had recurrent DH, with a mean of 5.17 haemorrhages over the 5-year period. Type 1 focal LD (p=0.0000, OR 7.17), glaucoma progression (p=0.0024, OR 0.32) and ArtDiff (p=0.0466, OR 1.04) were significantly associated as predictors of DH. No correlation between the size of the LD and DH occurrence (p=0.6449, Spearman rank correlation) was found.ConclusionFocal lamina cribrosa hole-type defects were significantly associated with an increase in DH occurrence over the preceding 5 years. The lack of association between defect size and DH suggests that DH and lamina defects may have separate links to the glaucomatous process.

Compressed 3D and 2D digital images versus standard 3D slide film for the evaluation of glaucomatous optic nerve features

SynopsisClinicians can feel confident compressed three-dimensional digital (3DD) and two-dimensional digital (2DD) imaging evaluating important features of glaucomatous disc damage is comparable to the previous gold standard of stereoscopic slide film photography, supporting the use of digital imaging for teleglaucoma applications.Background/aimsTo compare the sensitivity and specificity of 3DD and 2DD photography with stereo slide film in detecting glaucomatous optic nerve head features.MethodsThis prospective, multireader validation study imaged and compressed glaucomatous, suspicious or normal optic nerves using a ratio of 16:1 into 3DD and 2DD (1024×1280 pixels) and compared both to stereo slide film. The primary outcome was vertical cup-to-disc ratio (VCDR) and secondary outcomes, including disc haemorrhage and notching, were also evaluated. Each format was graded randomly by four glaucoma specialists. A protocol was implemented for harmonising data including consensus-based interpretation as needed.ResultsThere were 192 eyes imaged with each format. The mean VCDR for slide, 3DD and 2DD was 0.59±0.20, 0.60±0.18 and 0.62±0.17, respectively. The agreement of VCDR for 3DD versus film was κ=0.781 and for 2DD versus film was κ=0.69. Sensitivity (95.2%), specificity (95.2%) and area under the curve (AUC; 0.953) of 3DD imaging to detect notching were better (p=0.03) than for 2DD (90.5%; 88.6%; AUC=0.895). Similarly, sensitivity (77.8%), specificity (98.9%) and AUC (0.883) of 3DD to detect disc haemorrhage were better (p=0.049) than for 2DD (44.4%; 99.5%; AUC=0.72). There was no difference between 3DD and 2DD imaging in detecting disc tilt (p=0.7), peripapillary atrophy (p=0.16), grey crescent (p=0.1) or pallor (p=0.43), although 3D detected sloping better (p=0.013).ConclusionsBoth 3DD and 2DD imaging demonstrates excellent reproducibility in comparison to stereo slide film with experts evaluating VCDR, notching and disc haemorrhage. 3DD in this study was slightly more accurate than 2DD for evaluating disc haemorrhage, notching and sloping.