High risk but questionable reward. Corneal blindness is a leading cause of blindness worldwide and restoration of vision is limited to corneal transplantation. In uncomplicated cases, graft survival is >90%. However, in high risk individuals with vascularized corneas the rate of rejection increases to greater than fifty percent. A randomized double-blinded prospective study was performed to determine the effect of bevacizumab (which inhibits neovascularization) on endothelial immune rejection rate. Ninety-two patients were randomized to receive either subconjunctival bevacizumab (2.5mg/0.1ml) or a placebo at the time of their surgery and topical bevacizumab (10mg/ml) or a placebo four times a day for the following four weeks post-surgery. There was no significant decrease in the rate of graft failure after 52 weeks (61% in the bevacizumab group versus 64% in the placebo (P=0.055)). The endothelial rejection rate was also not significantly different with 10% in the bevacizumab group versus 19% in the placebo (P=0.20). However, there was a significant difference in endothelial rejection rate after extended follow-up (median follow-up 3-4 years) at the lead study site, which was 3% in the bevacizumab group versus 38% in the placebo (P=0.003). Overall, bevacizumab treatment in high-risk corneal transplantation, while positively correlated, does not significantly affect the endothelial rejection rate in the short term, however further studies with higher power and longer follow-up are needed as these findings may have greater impact in the long term care of patients.
Symptoms may include: coughing, sneezing, and a... retinal vein occlusion? There are well-documented systemic effects of the prothrombotic nature of COVID-19. A retrospective cohort study done by Kaiser Permanente utilized clinical data of patients before and after diagnosis to test for the incidence of retinal artery occlusions (RAOs) or retinal vein occlusions (RVOs). Per 1,000,000 patients, in the 6 month period after COVID-19 diagnosis, the crude incidence rate of RAOs had a non-significant increase from 2.31 to 3.00 (p = 0.44), while the crude incidence rate of RVOs increased significantly from 8.30 to 12.20 (p = 0.03). Patients had the highest crude incidence rates for retinal vascular occlusions in the 2 weeks before and 12 weeks following diagnosis, with RAO rates of 3.55 (p = 0.30) and RVO rates of 12.80 (p = 0.049). As new research emerges, clinicians should keep a watchful eye on patients with risk factors for potential retinal vascular occlusions following COVID-19 diagnosis.
Ophthalmologists 🤝 Neurosurgeons: the battle against increased intracranial pressure. Can optic nerve sheath fenestration (ONSF) be used safely in pediatric patients with increased intracranial pressure (ICP)? Idiopathic intracranial hypertension is the most common cause of increased ICP not related to mass in children. Elevated ICP and papilledema can result in lifelong visual field defects and blindness, and the severity of papilledema is positively correlated with the risk of visual loss. While acetazolamide is the drug of choice for initial treatment, medically refractory cases or individuals with severe vision loss at presentation may require surgical intervention. This retrospective chart review included 14 pediatric patients who underwent ONSF between 2009 and 2020 at the Children's Hospital of Philadelphia. Visual acuity improved from 20/138 to 20/68 in the operated eye (P=.0003) and from 20/78 to 20/32 in the non-operated eye (P=.02). Color vision and RNFL also improved in the operated eye. Extraocular motility and visual field mean deviation significantly improved in both the operated and non-operated eye. Improvements were observed as early as postoperative day 1. ONSF should be considered in children and young adults with papilledema and elevated ICP causing vision loss that is severe at presentation or refractory to standard medical management.
ZAP! Lasers can be cool, but let’s talk about their potential downsides. Individuals with narrow anterior chamber angles are often treated prophylactically with laser peripheral iridotomy (LPI) to decrease risk for angle-closure glaucoma. Previous literature suggests one potential complication of LPI is cataract formation; however, few studies have included adequate controls and follow-up time. The single-center ZAP trial included 889 patients diagnosed as primary angle closure suspects. One eye was randomized to receive YAG LPI while the other eye was just observed. Cataract progression was defined as change of ≥2 grades in any category of Lens Opacity Classification System III (LOCS III), or having cataract surgery during the 6-year follow-up period. After 6 years, LPI eyes had slightly higher average nuclear grades in nuclear opalescence and color (approximately 2.9 vs 2.8, p<0.001). However, there were no differences in cataract progression (21.2% in LPI vs 19.4% in control) or cataract surgery (1% for both). Visual acuity after 6 years was similar in both groups. Prophylactic YAG did not significantly alter risk of cataract progression or visual acuity after 6 years.
These days, when you mention Botox, no one raises an eyebrow! Although botulinum toxin formulations were first created by an ophthalmologist as a strabismus treatment, it is now popular for its cosmetic indications. In order to assess the safety profile of Botox injections, a meta-analysis of 9669 patients receiving cosmetic injections was performed to evaluate adverse effects. There was no difference in injection site reaction rates between the Botox-recipient group and placebo group. Specific adverse events were more likely to occur among patients treated with Botox rather than placebo, including eyelid/eyebrow malpositions (RR 3.55), facial palsies (RR 2.42), and headaches (RR1.45). Interestingly, even though the number of units per Botox injection, number of injections, and concentration of injections were not significantly associated with differences in adverse effects, the individual volume per injection was: patients with 0.1 mL or more of Botox was associated with higher adverse outcomes (RR 1.77) compared to patients with less than 0.1 mL of Botox (RR 1.19). While Botox resulted in some adverse events compared to placebo, additional studies with close monitoring of adverse events could better characterize Botox’s safety profile.
Question of the Week
A 25-year-old male presents with right-sided subcostal tenderness, dark urine, and jaundice. He reports a 60-pound weight loss over the last several months. Ocular examination is shown below. The patient has no past ocular history.
Which of the following is the most likely etiology of the patient’s symptoms?
A. Increased levels of serum ceruloplasmin
B. Autosomal recessive mutations in the ATP7B gene
C. Low copper diet
D. Chronic alcohol use