Neurotrophic Keratopathy After Herpes Zoster Ophthalmicus

Herpes Zoster Ophthalmicus: Presentation, Complications, Treatment, and Prevention

Herpes zoster (HZ) is caused by reactivation of latent infection of varicella zoster virus (VZV) in sensory (cranial, dorsal root) ganglia. Major risk factors for HZ are increasing age and immunosuppression. HZ ophthalmicus (HZO) is a subset of HZ with involvement of the ophthalmic division of the fifth cranial trigeminal nerve. Approximately 4-20% of patients with HZ develop HZO. Approximately 50% of patients with HZO develop ocular disease, among whom up to 25% develop chronic or recurrent disease. Common manifestations of ocular disease include conjunctivitis, keratitis, and uveitis, whereas optic neuropathy and retinitis are uncommon. Due to the potential for vision impairment, ocular involvement requires urgent ophthalmic consultation. Early recognition and timely treatment with antivirals may prevent ocular complications. HZO is preventable by vaccination against HZ. Vaccine efficacy/effectiveness studies have been largely conducted for HZ with few studies assessing HZO. Both the recombinant adjuvanted vaccine (RZV) and live-attenuated vaccine (ZVL) significantly reduce the incidence of HZ and HZO in older adults. RZV is more effective than ZVL. Data on the effectiveness of vaccines for prevention of recurrent disease in patients with HZO are limited; however, vaccination is recommended. Despite recommendations to vaccinate individuals likely to benefit from an HZ vaccine, coverage for adults remains suboptimal. Barriers to vaccination include patient beliefs about HZ or HZ vaccines, and factors related to healthcare providers. In particular, the lack of a recommendation from their primary care physician is often cited by patients as a reason for remaining unvaccinated. By encouraging vaccination against HZ, physicians not only prevent HZ and HZO but also potential vision loss due to HZO.Graphical abstract available for this article.

Herpes zoster ophthalmicus

Herpes zoster ophthalmicus (HZO) occurs when latent varicella zoster virus reactivates in the ophthalmic division of the fifth cranial nerve (CNV1). HZO commonly affects older and immunocompromised patients. This disease is considered an ophthalmic emergency due to the wide range of associated ocular symptoms, including severe chronic pain and vision loss. HZO is typically a clinical diagnosis due to its classic presentation of a unilateral vesicular eruption in the dermatomes corresponding to CNV1. Timely treatment is imperative to minimize ocular morbidity in HZO, given that ocular involvement is present in 50% of affected patients.

Corneal nerve changes in herpes zoster ophthalmicus: a prospective longitudinal in vivo confocal microscopy study

PURPOSE

To study the changes in corneal nerves and corneal sensitivity over a 6-month period in patients with herpes zoster ophthalmicus (HZO) compared with healthy subjects.

METHODS

This was a prospective longitudinal study on patients with newly diagnosed HZO. In vivo confocal microscopy (IVCM) corneal nerve parameters and corneal sensitivity were measured and compared between eyes with HZO, contralateral eyes and controls at baseline, 2 and 6 months.

RESULTS

Fifteen subjects with HZO and 15 healthy age and sex matched controls were recruited. HZO eyes revealed a reduction in corneal nerve branch density (CNBD) from baseline to 2 months (9.65 ± 5.75 vs. 5.90 ± 6.87/mm2, p = 0.018), and decreased corneal nerve fibre density (CNFD) at 2 months when compared with control (p = 0.025). However, these differences resolved by 6 months. HZO fellow eyes demonstrated increased corneal nerve fibre area (CNFA), corneal nerve fibre width (CNFW) and corneal nerve fractal dimension (CNFrD) at 2 months compared with baseline (p = 0.025, 0.031, 0.009). There was no change in corneal sensitivity for both HZO affected and HZO fellow eyes from baseline or over time, nor was it different from sensitivity in controls.

CONCLUSION

Corneal denervation was present at 2 months in HZO eyes, with an observed recovery by 6 months. HZO fellow eyes demonstrated increased corneal nerve parameters at 2 months, which could represent a proliferative response to nerve degeneration. IVCM is useful in monitoring corneal nerve changes, and is more sensitive in detecting nerve alterations than esthesiometry.

Amniotic Membrane Transplantation in the Management of Corneal Ulceration Following Infectious Keratitis

PURPOSE

To report on the outcomes of amniotic membrane transplantation (AMT) for corneal ulceration following infectious keratitis.

METHOD

In this retrospective cohort study of 654 patients with culture-proven infectious keratitis from 8 hospitals in Galicia (Spain), a total of 43 eyes of 43 patients (6.6%) underwent AMT for postinfectious corneal ulceration. The indications for AMT were sterile persistent epithelial defects, severe corneal thinning or perforation.

RESULTS

AMT was successful in 62.8% of cases, with 37.2% requiring an additional surgery. Median time to healing was 40.0 days (IQR 24.2-101.7 days) and final BCVA was lower than baseline (p = 0.001). Ulcers were large (>3 mm) in 55.8% of cases. Previous herpetic keratitis and topical steroid use were more common in patients who received AMT (p < 0.001). 49 microorganisms (43 bacteria and 6 fungi) were isolated.

CONCLUSIONS

AMT is a therapeutic option for complications following infectious keratitis, which present with a sterile persistent epithelial defect, significant corneal thinning or perforation.

Cost and Prescriber and Patient Characteristics of Cenegermin Use in the Medicare Population

PURPOSE

To assess the cost and prescriber and patient characteristics associated with the early use of cenegermin (OXERVATE) after its approval among Medicare beneficiaries to better define resource use and areas for improvement in the treatment of neurotrophic keratopathy.

DESIGN

Retrospective, cross-sectional study.

METHODS

Medicare Part D claims data of all cenegermin prescriptions from January 1, 2019, to December 31, 2020, were identified using its National Drug Code. Patients younger than 65 years and those with missing demographic characteristics were excluded. Information on patient and prescriber demographic characteristics, quantity of cenegermin prescription, gross drug costs, and patient out-of-pocket costs were extracted from each claim.

RESULTS

In 2019-2020, a total of 2410 Medicare beneficiaries aged 65 years or older were prescribed cenegermin. The mean (standard deviation [SD]) age of these patients was 77.3 (7.6) years. Most patients were female (63.6%), White (87.3%), and lived in urban areas (86.9%). The majority (72%) received a standard 8-week course. A total of 1025 clinicians prescribed cenegermin. Most were male (68.2%), in an urban setting (90.8%). The median (interquartile range [IQR]) duration of cenegermin therapy prescribed per patient by each clinician was 8 (7.5-8) weeks. Total gross drug cost of all cenegermin therapy over the study period was $287 million. Median (IQR) out-of-pocket patient cost was $5791 (180-7179).

CONCLUSIONS

Despite the clinical benefits of cenegermin therapy, the associated significant cost warrants further analysis of its cost-effectiveness in patient care, especially in comparison with alternative novel management options.

Magic Bullets: The Coming Age of Meaningful Pharmacological Control of the Corneal Responses to Injury and Disease

Corneal injuries from chemical burns, mechanical trauma, infections, immunological rejections, surgical complications, and some diseases are commonly associated with persistent epithelial defects (PED), neurotrophic epitheliopathy, scarring fibrosis, corneal neovascularization (CNV), and/or corneal endothelial damage that lead to vision loss. Several Food and Drug Administration (FDA) approved medications have recently become available, are currently in clinical trials, or are likely to enter clinical trials in the near future. For example, a 2-week course of topical human recombinant nerve growth factor is frequently an effective treatment for corneal neurotrophic epitheliopathy associated with PEDs. Topical losartan, an angiotensin converting enzyme II receptor antagonist that also inhibits TGF beta signaling, has been shown to effectively decrease myofibroblast generation and scarring fibrosis in alkali burn injury and Descemetorhexis rabbit models. Small molecule topical tyrosine kinase inhibitors, such as sunitinib and axitinib, FDA approved as chemotherapeutic agents to treat specific cancers, have also been found to be effective topical inhibitors of CNV in animal and human trials. Rho-kinase inhibitors, such as ripasudil and netarsudil, that are currently approved agents for the treatment of glaucoma in some countries, have been shown to stimulate corneal endothelial proliferation in animal studies and human trials, and may accelerate the regeneration of Descemet's membrane. These agents, as well as other drugs in development, will be used in targeted combinations to treat corneal pathophysiology associated with epithelial healing disorders, stromal scarring fibrosis, CNV, and corneal endothelial injury during the next decade.