Ocular diseases associated with atopic dermatitis (AD) are collectively called “atopic eye disease.” The three major complications are cataract, retinal detachment, and keratoconus, with long-term eye rubbing and tapping being the main mechanisms of onset.
AD is a chronic inflammatory skin disease with an immunological background, and the risk of ocular complications is particularly high when skin lesions on the eyelids and face are severe. According to a survey by the Ministry of Education, Culture, Sports, Science and Technology (2004–2006), the prevalence rate is 5.5% on average among elementary, junior high, and high school students, and approximately 2–3% of adults are also affected.
| Ocular complication | Incidence | Main mechanism |
|---|---|---|
| Atopic cataract | Approximately 10–25% of AD patients | Physical irritation from eye rubbing and influx of eosinophil granule proteins into the eye |
| Retinal detachment | Approximately 0.5–8% of AD patients (varies by report) | Zonular rupture and retinal tear due to eye rubbing |
| Keratoconus | Corneal shape abnormality in approximately 7–30% of AD patients | Mechanical deformation and weakening of the corneal stroma due to eye rubbing |
The key findings for diagnosing AD are: (1) itching, (2) skin rash (distribution and characteristics of eczematous lesions), (3) course (chronic relapsing), and (4) atopic predisposition (family history and associated allergic diseases).
Regarding the incidence of cataracts in patients with a habit of eye rubbing or tapping, a study of 101 cases at the Mayo Clinic (Brunsting report) reported approximately 10% 6). Rapid vision loss in young individuals (teens to 30s) is characteristic, showing a clinical picture different from age-related cataracts.
Yes. The risk of cataracts, retinal detachment, and keratoconus is increased. The risk is especially high when there is severe dermatitis on the face and eyelids, and when there is a habit of rubbing or hitting the eyes. Early ophthalmologic follow-up is important.
Atopic cataract
Age of onset: Commonly occurs in young people in their teens to thirties. Rapid vision loss.
Characteristics of opacity: “Star-shaped,” “asteroid,” or “crack-like linear opacities” under the anterior capsule. The morphology resembles traumatic (contusion) cataract, and differentiation from steroid-induced cataract with posterior subcapsular opacity is important.
Progression: Often rapidly progressive, reaching severe opacity within weeks to months.
Retinal detachment
Keratoconus
Pathology: Progressive corneal protrusion and thinning.
Symptoms: Decreased visual acuity and glare due to irregular astigmatism. Visual acuity that cannot be fully corrected with glasses occurs.
Association: Mechanical stimulation from eye rubbing is a modifying factor in the onset and progression. It is more frequent in cases of atopic dermatitis complicated by allergic conjunctivitis9).
Blepharitis / Allergic Conjunctivitis
Findings: Eyelid swelling, itching, eye discharge, papillary reaction of the conjunctiva.
Characteristics: In patients with severe atopic dermatitis, it takes a chronic course and, by inducing eye rubbing behavior, further increases the risk of developing cataracts, retinal detachment, and keratoconus.
Complications: Corneal epithelial damage and keratitis due to repeated anterior segment inflammation may occur.
Slit-lamp examination reveals the morphology of anterior subcapsular opacities (star-shaped, stellate, or cracked-ice appearance). This morphology is clearly different from steroid-induced cataracts (posterior subcapsular opacity) and closely resembles traumatic cataract, which is a key diagnostic point. Fundus examination with dilated pupils carefully evaluates peripheral retinal tears and detachments.
It occurs in young individuals (teens to 30s) and presents characteristic star-shaped or stellate opacities in the anterior subcapsular region of the lens. Physical stimulation from habitual eye rubbing or tapping is involved in its onset, and it differs from age-related posterior subcapsular opacity in morphology, age of onset, and mechanism.
Eye rubbing and tapping behavior is the greatest modifying factor for atopic eye disease. Itching due to blepharitis triggers this behavior, and long-term physical stimulation to the eyeball causes ocular complications through the following pathways:
The involvement of topical steroids in the development of atopic cataract is considered unlikely. Atopic cataracts were reported before the clinical introduction of steroids (before the 1950s)6), and no significant change in cataract incidence has been observed before and after the introduction of steroids. However, caution is needed because steroid eye ointment can enter the conjunctival sac and cause elevated intraocular pressure.
The more severe the dermatitis on the face and eyelids, the stronger the urge to scratch the eyes, increasing the risk of ocular complications. Serum TARC levels, serum LDH levels, peripheral blood eosinophil count, and serum total IgE levels are indicators of AD severity and are also used as indirect indicators of ocular complication risk.
Population-based cohort studies have shown that AD patients have a significantly higher risk of cataract, glaucoma, and retinal detachment compared to non-AD individuals12).
Eosinophil activation due to enhanced type 2 immune responses (IL-4, IL-13, IL-31) also occurs locally in the eye. Allergic inflammation is triggered in the conjunctiva, which can lead to goblet cell proliferation, giant papilla formation, and corneal epithelial damage2)3).
| Examination | Evaluation items | Notes |
|---|---|---|
| Slit-lamp microscopy | Confirmation of anterior subcapsular opacity morphology (star-shaped, stellate, cracked-ice pattern) | Differentiation from steroid-induced cataract (posterior subcapsular opacity) |
| Dilated fundus examination | Confirmation of retinal tear, detachment, and peripheral degeneration | Recommended at least once a year for all AD patients with a history of eye rubbing |
| OCT | Detailed evaluation of retinal layer structure and confirmation of macular abnormalities | Useful for pre- and post-operative follow-up |
| Corneal topography | Screening for keratoconus and keratoglobus | Performed in young AD patients with irregular astigmatism |
| Zinn zonule evaluation | Preoperative assessment of rupture and fragility | Essential before cataract surgery. UBM and anterior segment OCT are useful |
| Blood test | Peripheral blood eosinophil count, serum total IgE, LDH, TARC levels | Assessment of AD severity and disease activity |
The diagnosis centers on morphological confirmation of anterior subcapsular opacity using slit-lamp microscopy. Characteristic findings include “star-shaped,” “asteroid,” or “crack-like linear opacities,” which can be differentiated morphologically from steroid-induced cataract that presents with posterior subcapsular opacity. This type of cataract often occurs in younger patients with relatively soft nuclei, making preoperative assessment of nuclear hardness important. Lens mobility and the state of the zonules of Zinn are evaluated preoperatively using ultrasound biomicroscopy (UBM) or anterior segment OCT.
Thorough examination of the peripheral fundus under mydriasis is essential. AD patients have a higher frequency of juvenile lattice degeneration and tears compared to non-AD patients 8). Acute onset of floaters or photopsia requires urgent fundus examination.
If there is severe dermatitis on the face or eyelids, at least annual ophthalmologic examination is recommended. More frequent checks are desirable if the child has a habit of rubbing or hitting the eyes. If decreased vision, floaters, or photopsia are noticed, seek medical attention promptly.
| Complication | Severity | Treatment |
|---|---|---|
| Atopic cataract | Decreased vision | Phacoemulsification (PEA) + intraocular lens implantation. Preoperative evaluation of zonules and retina is mandatory. |
| Retinal detachment | Tear only | Laser photocoagulation (preventive treatment) |
| Retinal detachment | With detachment | Vitrectomy / Scleral buckling surgery |
| Keratoconus | Mild | Optical correction with RGP (rigid gas permeable) contact lenses |
| Keratoconus | Progressive | Corneal cross-linking (CXL) to halt progression |
| Keratoconus | Severe | Corneal transplant (penetrating or deep anterior lamellar keratoplasty) |
| Blepharitis/Periorbital AD | Mild | Application of moisturizers such as Propet eye ointment |
| Blepharitis/Periorbital AD | Moderate to severe | Predonin eye ointment, apply appropriate amount twice daily, adjust dose according to symptoms |
| Blepharitis/Periorbital AD | Steroid-refractory cases | 0.03% or 0.1% Protopic ointment, apply once or twice daily |
Phacoemulsification (PEA) is performed and an intraocular lens is inserted. The procedure is basically the same as for age-related cataract, but the following points require attention.
Since eyelid and periorbital dermatitis directly cause eye scratching, active control in collaboration with a dermatologist is important.
Mild cases: Apply moisturizers such as white petrolatum ophthalmic ointment. Maintaining skin barrier function is the basis of long-term management.
Moderate to severe cases: Use steroid ophthalmic ointment.
If no improvement with steroid ophthalmic ointment: After consulting a dermatologist, use 0.03% or 0.1% Protopic ointment (tacrolimus hydrate).
Controlling eye scratching and tapping behavior is fundamental to preventing all ocular complications. Ophthalmologists need to work with dermatologists to actively treat facial AD and blepharitis. With the widespread use of tacrolimus ointment, control of blepharitis has improved, and a decrease in the incidence of atopic cataracts is expected.
Ophthalmic steroid ointments (such as prednisolone ophthalmic ointment) can be used around the eyes, but their pharmacological potency is weak. Since they may increase intraocular pressure if they enter the conjunctival sac, be careful not to get them into the eye when applying. Regular intraocular pressure checks are recommended during long-term use.
The development of ocular diseases associated with AD results from physical stimuli starting with eye rubbing and hitting behaviors, which damage ocular tissues through multiple pathways.
Mechanism of cataract development:
Mechanism of retinal detachment:
Mechanism of keratoconus:
In AD, enhanced type 2 immune responses (overproduction of IL-4, IL-13, IL-31) activate eosinophils, which release inflammatory mediators locally in the eye. Th2-type allergic inflammation also occurs in the conjunctiva, leading to goblet cell proliferation, giant papilla formation, and corneal epithelial damage3).
The following evidence supports that topical steroids are not the main cause of atopic cataract development: ① Cataracts were reported before the clinical introduction of steroids in the 1950s6); ② No significant change in cataract incidence was observed before and after the introduction of steroids. This suggests that atopic cataract is essentially caused by physical stimuli such as eye rubbing and tapping, as well as immunological mechanisms.
With the advent of tacrolimus ointment (Protopic), control of blepharitis and periorbital AD is expected to be better than with conventional topical steroid therapy. A virtuous cycle is anticipated: control of blepharitis → reduction of itching → reduction of eye rubbing → decreased incidence of atopic cataract, retinal detachment, and keratoconus1). Multiple reports have accumulated on the efficacy and safety of topical tacrolimus therapy for atopic blepharitis1).
Dupilumab (anti-IL-4 receptor alpha antibody) has been approved and widely used as a first-line biologic for moderate to severe AD. However, conjunctivitis has been reported in approximately 10-30% of patients during use5)10), and cases of anterior uveitis have also been reported. The exact mechanism of dupilumab-induced conjunctivitis is still under investigation, and many details of the pathology remain unclear. Ophthalmic monitoring is recommended during dupilumab use.
For management of conjunctivitis, artificial tears, low-concentration steroid eye drops, and cyclosporine eye drops are used, but discontinuation of dupilumab may be necessary in some cases5).
JAK inhibitors such as baricitinib, upadacitinib, and abrocitinib have been approved in Japan for moderate to severe AD. Ocular complications (especially increased risk of herpetic eye infections) are under ongoing investigation.
Regarding the inhibitory effect of corneal cross-linking (CXL) on the progression of AD-related keratoconus, reports of efficacy in young patients with AD as an underlying disease have been accumulating 11). It is thought that performing CXL after improvement in control of eye rubbing behavior leads to better long-term outcomes, but evidence on long-term outcomes is still being accumulated.
Population-based cohort studies have statistically quantified the association between AD and ocular complications (cataract, glaucoma, retinal detachment) 12). Future challenges include refining risk factors through larger prospective studies and elucidating the causal pathway linking AD severity, eye rubbing behavior, and the development of ocular complications.
