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February 22, 2023


The most important ophthalmology research updates, delivered directly to you.
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In this week's issue
  • Authors from multiple specialties – including ophthalmology – often confuse the term papilledema and use it inappropriately in publications.
  • Study finds that 0.05% atropine delays both the incidence of myopia and fast myopic shift in children compared to 0.01% atropine and placebo.
  • Monitoring ganglion cell layer may be better for glaucoma suspects, while monitoring inner plexiform layer thickness may be better for patients with established glaucoma when examining macular OCT.

Papilledema versus optic disc edema: What’s the big deal?

Ophthalmology

Papilledema, optic disc edema… tomato, tomaato… Optic disc edema (ODE) is a general term used to describe inflammation of the optic nerve fibers from any type of optic neuropathy, whereas papilledema specifically signifies ODE from elevated intracranial pressure (ICP). Despite their differences, these terms are often misused. A recent cross-sectional systematic review identified published case reports using the term "papilledema" to assess the prevalence of incorrect usage of the term. They categorized these into type 1 errors (“papilledema” without evidence of elevated ICP), type 2 errors (“papilledema” before finding evidence of elevated ICP), type 3 errors (both type 1 and 2), or no error. Of the 722 case reports, 66.8% had errors (2% type 1, 47% type 2, 15% type 3) while 33% had no errors). Fewer errors were noted in higher impact journals, non-open-access publications, and countries with English as the official language. Despite a lower prevalence of errors with ophthalmologists compared to neurologists and neurosurgeons, each of these specialties had an error prevalence of >30%. There was no association between error prevalence with publication year or number of citations. In summary, “papilledema” is often misused, even amongst ophthalmologists. This can lead to inappropriate management and suboptimal outcomes, potentially causing life- or vision-threatening complications.

Atropine eye drops to reduce myopia progression in children

JAMA Ophthalmology

Why did the myopic person refuse to go skydiving? Because they couldn't see the point! Myopia, commonly known as nearsightedness, is the most common type of refractive error worldwide and is increasing in prevalence. Pathologic myopia, commonly defined as more myopic than -8.0 D, is associated with vision-threatening complications such as progressive retinal thinning, choroidal neovascularization, and retinal detachment. A randomized controlled trial investigated the efficacy of low-concentration (0.05% and 0.01%) atropine eye drops as myopia prophylaxis in children as compared to placebo. A total of 353 participants, aged 4 to 9 years, with less than one diopter of myopia and/or astigmatism, completed the 2-year trial. The 0.05% atropine group had a significantly lower 2-year cumulative incidence of myopia (difference, 24.6% [95%CI,12.0%-36.4%]) and percentage of patients with fast myopic shift (difference, 28.9% [95% CI, 16.5%-40.5%]) as compared to the placebo group. However, there was no significant difference between the 0.01% atropine group and placebo. The authors conclude that further research is necessary to replicate the findings and evaluate the longer-term safety of atropine.

Seeing the differences: a comparative study of macular layers in glaucoma suspects and sufferers

American Journal of Ophthalmology

Maculae are like onions - they have layers! Measurements of certain layers in the inner macula, particularly the ganglion cell layer (GCL) and the inner plexiform layer (IPL),   using macular optical coherence tomography (OCT) are useful in monitoring glaucoma incidence and progression. This prospective cohort study examined the maculae of 176 eyes (64 glaucoma suspects and 112 established glaucoma subjects) using macular OCT to determine the rates of change of the GCL and IPL at different stages of disease. In glaucoma suspects, the GCL demonstrated faster rates of thinning compared to the IPL (-0.69 [0.05 SD] vs -0.33 [0.04 SD]) while the opposite was found in established glaucoma subjects, with the IPL thinning faster than the GCL (-0.47 [0.03 SD] vs -0.28 [0.02 SD]). While limitations may exist due to the resolution quality of current OCT devices that may contribute to inaccurate automated segmentation algorithms, the results of this study suggest that monitoring GCL changes is more efficacious for glaucoma suspects, while monitoring IPL thickness is better for established glaucoma subjects.

The link between chronic stress and myopia

British Journal of Ophthalmology

Chronic stress is bad for your vision! Chronic stress response arising from competitive educational environments causes activation of the sympathetic nervous system (SNS), reaching different organs such as the eyes. This 2019-2020 longitudinal study investigated the association between SNS activation and myopia progression in 273 primary school-aged children in Shanghai. SNS activity has been associated with choroidal thickness and axial length. Axial length (AL), four quadrants of the choroidal thickness (ChT), spherical equivalent refraction (SE) and urine catecholamines were recorded. Dopamine, norepinephrine, and epinephrine served as a proxy for SNS activity. Children with higher SNS activity had decreased ChT, longer AL, and quicker AL elongation. Every 1 µg/L increase in epinephrine is associated with a 1.60 (95% CI 0.30 to 2.90) µm decrease in average ChT, and every 1 µg/L increase in norepinephrine is associated with a 0.53 (95% CI 0.08 to 0.98) µm decrease in ChT. Limitations of the study include use of urine catecholamine concentrations without creatinine correction as the sole marker for SNS activity. This study may have implications in how chronic stress can cause myopia.

Retina

Delayed presentation patterns in CRAO

Ophthalmology Retina

We’ve all heard time is brain…but what about time is retina? A central retinal artery occlusion (CRAO) is an acute ischemic stroke of the retina that typically presents as painless, severe monocular vision loss. With less than 18% of patients exhibiting any spontaneous functional recovery, acute conservative interventions to decrease intraocular pressure, dislodge the embolus, or dilate the retinal vasculature have been attempted with poor efficacy. Intravenous thrombolytic therapy has been gaining traction in recent years as a promising option; however, treatment must be administered quickly (within 4.5 hours) to achieve full benefit. In this retrospective cohort study, Shah et al. evaluated the presentation patterns of 484 patients with non-arteritic (meaning non-inflammatory) CRAO. Mean time from symptom onset to evaluation by a healthcare provider was 25.7 hours, with 247 patients (51%) making contact within the 4.5-hour window and only 81 patients (16.7%) receiving diagnostic confirmation by an ophthalmologist within that time frame. First contact was made most commonly at an emergency department (60.3%) followed by an ophthalmologist office (27.5%). This study illustrates that patients with CRAO often have delayed presentation with definitive ophthalmic diagnosis frequently occurring outside the therapeutic window for thrombolytic therapy. Both educational and infrastructural healthcare reforms should be considered in the future to improve patient outcomes. 

Lens Landmarks

If an apple-a-day keeps the doctor away, what keeps away endophthalmitis? While endophthalmitis is rare, invasion of the globe during cataract surgery is a risk factor and must be taken into consideration before, during, and after the procedure. In an effort to better understand ways to prevent such a postoperative complication, the ESCRS (European Society of Cataract and Refractive Surgeons) endophthalmitis study coordinated 24 ophthalmology clinics/units across Europe to gather data. Researchers in this partially masked, placebo-controlled, randomized clinical trial enrolled 13,698 participants to evaluate the prophylactic effect of intracameral cefuroxime injection and/or perioperative levofloxacin eyedrops on the incidence of endophthalmitis after cataract surgery.

Key Points:
  • Use of intracameral cefuroxime at the end of cataract surgery significantly reduced the risk of postoperative endophthalmitis.
  • The total reported cases of endophthalmitis were nearly 5 times less in groups that utilized intracameral cefuroxime compared to those that did not (OR, 4.59; 95% CI, 1.74-12.08; P = 0.002).
  • Cases of microbiologically proven endophthalmitis were more than 5 times less in groups that utilized intracameral cefuroxime compared to those that did not (OR, 5.32; 95% CI, 1.55-18.26; P = 0.008).
The ESCRS endophthalmitis study earns its landmark status as it was among the trailblazers of endophthalmitis prophylaxis as it relates to cataract surgery. The results of the study influenced surgical technique in the following years and widened the discussion on how to best prevent endophthalmitis after cataract surgery.

Question of the Week
A 4 month old infant develops with desquamative rash, persistent rhinitis, anemia, generalized lymphadenopathy, and bowed shins. She was noted to have failed her newborn hearing screening. 
Which of the following findings would most likely be present on ophthalmic examination of this newborn child?

A. Interstitial keratitis
B. Speckled hyperpigmentation of the retinal periphery and chorioretinitis
C. Argyll-Robertson pupils
D. Granulomatous anterior uveitis


 
Keep scrolling for answer or click here

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