Current Issue

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In this week’s issue:

• A retrospective study reveals incidence and risk factors for endophthalmitis following glaucoma surgeries among Medicare patients.
• Dual use of e-cigarettes and cigarettes is associated with increased and more severe ocular symptoms in young users.
• Morning blood pressure surge may be an independent predictor of increased visual field progression in normal tension glaucoma patients.

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Ophthalmology 

Unveiling the risk: Endophthalmitis incidence in modern glaucoma surgery techniques

Endophthalmitis is a rare but serious complication that can develop after ocular trauma, including intraocular surgery. It has been shown that endophthalmitis more commonly occurs after glaucoma surgery compared to other intraocular surgeries, but with newer techniques including microinvasive glaucoma surgery (MIGS), this study sought to validate these findings. This study analyzed over 460,000 Medicare patients who underwent glaucoma surgery, of which over 300,000 were combined with cataract surgery. MIGS was the most common glaucoma procedure performed followed by trabeculectomy, tube shunt, and others. There were 572 cases of endophthalmitis identified following all glaucoma surgeries. Endophthalmitis incidence following surgery were as follows: glaucoma 1.5 (CI 1.3-1.7), combined cataract/glaucoma 1.1 (CI 1.0-1.2), and cataract surgeries alone 0.8 (CI 0.8-0.8) per thousand procedures. The median day of diagnosis of endophthalmitis for glaucoma surgeries was 16.5 days vs. combined cataract/glaucoma at 8 days vs. cataract surgeries alone at 6 days. Compared to MIGS, tube shunts were the only surgery type to be a significant risk factor for endophthalmitis for both standalone (aOR 1.8) and combined surgery (aOR 1.8). Age (aOR 1.03) and male gender (aOR 1.46) were significant risk factors only for combined cataract and glaucoma surgeries. These data shed new light on the incidence of endophthalmitis following the newer techniques in glaucoma surgery. 

JAMA Ophthalmology

Worsening ocular symptoms in users of cigarettes and electronic cigarettes

E-cigarettes? E-yikes. With the rise of e-cigarette use among adolescents and adults alike, information on the ocular problems that their use may cause is relatively scarce. Tobacco, which has been extensively studied, has been known to worsen glaucoma, cataract formation, uveitis, and other eye diseases. This study aimed to evaluate the relative prevalence of visual symptoms in users of e-cigarettes, cigarettes, or both compared to never users. This observational cross-sectional study included individuals aged 13-24 who identified as users of these products, and stratified them based on recency and frequency of use. In multivariable logistic regression analysis, this study found no statistically significant associations between e-cigarette use alone and visual symptoms. Cigarette use alone was associated with burning/stinging, blurry vision, pain/aching, and dryness/gritty sensation. Dual-use of both cigarettes and e-cigarettes appeared to worsen symptoms compared to cigarette use alone, with statistically significant associations for generalized discomfort, pain/aching, burning/stinging, itching, redness, dryness/gritty sensation, glare/light sensitivity, blurry vision, headaches, and tiredness/eye strain. Although this study found no direct associations between e-cigarette use and visual symptoms, it appears that e-cigarette use may worsen symptoms in cigarette users. It is difficult to ascertain if the differences in symptoms between the three groups are due to substance properties, interactions between substances, or differences in substance use behavior. 

American Journal of Ophthalmology

Visual field loss in normal-tension glaucoma with morning blood pressure surge

Do you consider yourself a morning person? You might want to think again! Normal-tension glaucoma (NTG) is a subtype of glaucoma that is characterized by optic nerve damage and visual field loss in the absence of elevated intraocular pressure. Prior literature has demonstrated that variable blood pressure during the daytime may be useful as a predictor of progressive visual field loss in patients with NTG. It has also been documented that blood pressure tends to be higher in the morning hours, possibly due to neurohormonal changes (morning blood pressure surge [MBPS]). The impact of MBPS on visual field progression is the primary focus of this retrospective cohort study. This study analyzed 127 eyes of 127 hypertensive patients newly diagnosed with NTG. Patients underwent 24-hour ambulatory blood pressure monitoring with at least 5 serial IOP measurements and serial visual field examinations over a 2-year follow-up period. Cox proportional-hazards survival models showed that risk of visual field progression was increased in patients with greater MBPS (HR 1.033) and reduced in patients with lower nighttime mean arterial pressure trough (HR 0.965). While a small sample size, among other limitations, restricts the generalizability of this study, it highlights the importance of blood pressure control in patients with NTG, especially in the morning. Identifying MBPS as a risk factor for visual field progression is an early step toward optimizing hypertensive management to improve visual outcomes. 

British Journal of Ophthalmology

Location is key in ocular adnexal lymphoma and mortality

What do real estate and ocular adnexal lymphoma have in common? Location, location, LOCATION! Ocular adnexal lymphomas (OALs) are rare cancers that develop in various parts of the eye area, including orbital soft tissue, conjunctiva, eyelids, lacrimal gland, or lacrimal drainage apparatus. They make up about 2% of extranodal lymphomas. Historically, conjunctival lymphomas were thought to have a better prognosis than those in the eyelid, but recent research suggests that eyelid and lacrimal gland lymphomas may have a higher risk of spreading systemically. The study aimed to determine if the location of OAL within these structures is a significant predictor of mortality and assessed the American Joint Committee on Cancer TNM staging system's prognostic value based on primary tumor location and local disease extent. This retrospective study included patients with OAL from seven international centers from 1980 to 2017. The study of 1168 patients revealed that 97% of ocular adnexal lymphomas (OAL) were of B-cell origin, with major subtypes being extranodal marginal zone B-cell lymphoma (EMZL), follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL), and mantle cell lymphoma (MCL). Higher TNM T-stage correlated with increased disease-specific mortality. All-cause mortality was lower in T1 disease than T2 but not after adjusting for other factors. Primary eyelid EMZL had higher all-cause mortality than conjunctival EMZL. For FL, DLBCL, and MCL, no significant mortality differences were observed by OAL location or TNM T-category. This study is limited by its retrospective nature and reliance on data from multiple centers, which may introduce variability in data quality and treatment approaches.

Journal of Neuro-Ophthalmology

Can fluoxetine aid in vision recovery after acute ischemic stroke?

I can’t see! Patients who develop homonymous hemianopia as a result of stroke are thought to have a miniscule chance of complete spontaneous recovery. The potential for fluoxetine, a common selective serotonin reuptake inhibitor, to improve non-visual outcomes post-stroke has been a subject of many investigations. To investigate the potential for fluoxetine to improve visual outcomes, researchers randomized 17 adults to fluoxetine and placebo groups within 10 days following ischemic stroke resulting in isolated homonymous hemianopia. The primary end point was improvement of perimetric mean deviation by automated 24-2 visual field perimetry. Improvement was greater in the fluoxetine group (64.4%) compared to the placebo group (26.0%), although this result was not statistically significant (P = 0.06). When comparing complete recovery of the original blind field between groups, 60% of those receiving fluoxetine achieved complete recovery compared to 14% receiving placebo. This difference was statistically significant (OR = 7.22). These preliminary data suggest that fluoxetine may become a subject of larger randomized clinical trials intended to help restore vision in patients with debilitating stroke. 

Steroids for Corneal Ulcers (SCUT) - 2012

Can you count on corticosteroids to do the scutwork in bacterial keratitis? In the 2012 SCUT study, patients with known bacterial corneal ulcers were randomized to treatment with prednisolone (n = 250) and placebo (n = 250) 48 hours after receiving Vigamox.

Key Points:

• In the full population, there was no statistical difference in outcomes between the two groups. 
• For patients with more severe presentation (e.g., CF or worse vision, central ulcers), corticosteroids led to an approximate 2-line improvement.

Overall, the SCUT study is a landmark study because it showed that topical corticosteroids were not dangerous in the treatment of bacterial corneal ulcers and actually led to improved outcomes in a subset of patients with more severe presentations.

A 14-year-old girl was referred by her pediatrician for 6 months of blurry vision. At the first examination, her best-corrected visual acuity was 20/40 in the right eye and 20/40 in the left eye. Past medical history shared by her pediatrician also noted ocular melanocytosis, prominent axillary freckling, soft bumps on her back, and 7 cutaneous cafe au lait spots that have been present since childhood. A key slit lamp examination finding is shown. 

What are the suspected findings shown from the slit lamp exam?

A. Brushfield spots

B. Mammillations

C. Lisch nodules

D. Ocular freckles

Click Here For Answers!