Eyelid Disease

Abstract

Eye symptoms are a common presentation in general practice. According to the RCGP, they account for 4 500 000 GP consultations and cost the UK economy £22 billion each year. Both patients and practitioners are understandably anxious about eye problems, as vision is a very delicate and vital sense. In this article we will discuss the most common eyelid disorders, the pathophysiology, signs and symptoms, and primary care management options. The plethora of overlapping symptoms and aetiologies of eyelid disorders often leads to blanket management plans in general practice and the underlying diagnosis can be mismanaged, leading to persisting problems.

Clinical case scenario

Helga is a 61-year-old typist who attends morning surgery. Over the last 5 months she reports having sore gritty eyes, particularly towards the end of the day. They often tend to go pink and sometimes water (tears) and she complains her eyelids are itchy and can become puffy.

She has had no change to her vision and last visited her optician 1 year ago where everything was fine. She has a past medical history of rosacea.

Anatomy and physiology

In order to understand eyelid disorders, it is important to recognise the anatomical structures of the ‘lacrimal functional unit’. The International Dry Eye Workshop has defined this apparatus of interdependent structures as consisting of the lacrimal glands, cornea, conjunctiva, meibomian glands, and eyelids. Their innervation operates to ensure a constant lubricated environment for optimum eye movements and vision (Lemp et al., 2007). The eyelids are composed of an external layer of skin that coats the anterior orbicularis oculi muscle and innervated by the seventh cranial nerve, which causes it to close the lids. Internally, the lids are reinforced by the tarsal plates and lined with conjunctiva. The upper lid also benefits from the levator palpebrae and Muller's muscles inverted by the third cranial nerve to help raise the lid and open the eye.

The tear film, formed from the lacrimal glands, is predominantly aqueous in nature, but contains a small percentage of lipid, which is delivered by the meibomian glands located along the length of the eyelid margins. This creates a barrier between the vulnerable ocular surface and the exterior atmosphere, as well as providing lubrication, nutrition and antimicrobial functions. Collectively, this fine physiology prevents evaporation of the film and maintains a hydrated ocular surface.

The cornea is the most important, yet fragile, structure, contributing to refraction and focusing of light to optimise vision. Sitting comfortably in the orbit, it is encased by the eyelid structures which help to maintain its integrity and provide protection. An exposed cornea will inevitably suffer abrasions, epithelial defects, vascularisation and infection, manifesting as pain, irritation and changes in vision. A frequent and repeatedly exposed cornea can lead to scarring and eventual visual loss. Given the significance of this situation, recognition of the anatomy and correct diagnosis of underlying pathologies is vital. Due to the interdependence of these structures, a problem related to any part of the apparatus above can have a domino effect on other structures, leading to longer-term visual problems.

Common eyelid presentations and management

Eyelid disorders can broadly be divided into several categories of pathology including inflammatory, infective, structural causes and benign or malignant tumours. The consequences of these vary greatly from the asymptomatic and self-limiting to sight- and life-threatening problems that require immediate attention. In this article, we will discuss the common conditions and their associated pathology (Table. 1).

Table 1.

Common eyelid diseases and pathology.

Pathology	Condition
Inflammatory	• Blepharitis • Stye (sterile) • Chalazion
Infective	• Stye • Preseptal cellulitis
Structural	• Xanthelasma • Entropion • Ectroption
Tumours	Benign: • Sebaceous cyst Malignant: • Basal cell carcinoma • Squamous cell carcinoma

Blepharitis

Blepharitis or inflammation of the eyelids is one of the most common presentations of an eyelid disorder. Blepharitis can often be divided into anterior or posterior depending on the anatomical site affected, although there is considerable overlap and often both are present simultaneously. Blepharitis is much more common in adults than children hence prevalence increases with age (Shtein, 2020). The aetiology of this stubborn condition is complex and multifactorial.

Anterior blepharitis is less common than posterior blepharitis and is characterised by inflammation at the base of the eyelashes (Fig. 1). It tends to affect younger patients more commonly than its posterior counterpart.

Figure 1.

Anterior blepharitis with the classic inflammation and crusting at the base of the lashes.

Chronic Infection from Staphylococcus aureus has been identified as a key cause (O’Callaghan, 2018). As a common commensal, this bacterium can often be cultured from the ocular surface. Repeated infections of the eyelids by the bacteria directly, through their toxins or by means of allergic reactions lead to obstruction of the finer meibomian glands, limiting the lipid-rich contribution to the tear film. Consequently, this altered tear haemostasis with reduced lubricating properties causes faster tear evaporation and a drier ocular surface. Additionally, a reduction in immune components, such as lysozymes and immunoglobulins, alters resistance to bacteria, creating susceptibility to infection and gland abnormalities (Auw-Haedrich and Reinhard, 2008).

Posterior blepharitis is the more common form, characterised by inflammation at the meibomian gland level (Fig. 2). Meibomian gland dysfunction leads to hyperkeratinisation, inflammation and eventually fibrosis of the glands. This also promotes a drier ocular environment, predisposing patients to the development of blepharitis and chronic dry eyes.

Figure 2.

Posterior blepharitis with characteristic posterior lid inflammation and meibomian gland plugging.

Chronic dermatological conditions may also be implicated as predisposing factors. Seborrheic dermatitis is characterised by greasy and scaly skin often affecting the face and scalp. Up to 46% of patients with seborrheic dermatitis are found to have coexistent blepharitis (Huber-Spitzy et al., 1991). Acne rosacea, a condition, recognised by a papular pustular rash, telangiectasia and facial flushing has also been reported in between 20 and 40% of patients with blepharitis (McCulley et al., 1982).

Blepharitis typically affects both eyes and often presents with acute-on-chronic symptoms that include:

Sore, itchy, erythematous and swollen eyelids

Gritty sensation and stinging of the eyes

Scaling of eyelid skin

Crusts and matted eye lashes

Epiphora (excessive tearing)

Injected eyes

Light sensitivity

Transient blurring of vision

Blepharitis is a clinical diagnosis based on a detailed eye examination, with emphasis on the eyelids and the anterior surface of the eye. It is therefore important to undertake close inspection using a bright light, to assess eyelid margins, skin texture, appearance of the bases of the lashes and meibomian gland openings by applying mild lid inversion. This can help distinguish anterior from posterior blepharitis.

Blepharitis can be managed effectively in general practice. Treatment is primarily conservative and includes applying hot compresses, lid massage, lid washing and artificial tears (National institute of Clinical Excellence (NICE), 2019a). This is collectively referred to as ‘lid hygiene’ and is rigorously emphasised for all patients (Box 1).

Box 1.

Summary of lid hygiene measures.

Hot compress: Patients are advised to apply a hot flannel/microwavable eye bag over closed eyelids for 3 minutes. This aims to soften the solidified meibomian secretions and promote circulation to the glands.

Lid massage: Perform vertical eyelid massage from top of the lids down to express and clear the softened secretions out of the glands ready to be cleaned away.

Lid washing: Perform gentle washing of the eyelid margins using a cleanser, generally advised to use dilute baby shampoo (1-part shampoo in 10 parts warm water), which can be placed on a clean cloth or cotton swab. Gently, but firmly, clean along the lid margin to remove debris.

Lubrication: Advise using artificial tears and lubrication gels regularly to ensure a hydrated ocular surface.

If primary eyelid hygiene measures are ineffective, medical management options, including the use of antibiotics, can be considered. For anterior blepharitis, topical antibiotics (chloramphenicol 1% ointment) can be rubbed into the lid margins. For posterior blepharitis oral antibiotics (Doxycycline or other tetracyclines) are preferred and can also be considered for anterior blepharitis refractory to topical treatment (NICE, 2019a). Where patients do not respond to treatment, symptoms are severe or diagnostic uncertainty exists, referral to secondary care is indicated.

Styes

Styes are essentially boils of the eyelid and are also known as Hordeola. They can be divided into internal and external depending on the anatomy. External styes arise from the sebaceous glands of the eyelash follicle (the glands of Zeiss) or from the apocrine glands of Moll, both found in the lid margins. Internal styes are attributed to meibomian glands, which are located on the underside of the eyelids and occur when there is gland dysfunction or infection (Ghosh and Ghosh, 2020).

Styes are a very common presentation of eyelid lesions in general practice. They present as a pathognomonic painful erythematous pustule affecting the lid with no change to the vision. The diagnosis is clinical, based on history and appearance of the lesion on examination. S.aureus is the common causative pathogen, although styes can also be sterile (Ghosh and Ghosh, 2020).

Patients with dermatological conditions such as rosacea and seborrheic dermatitis have a greater propensity for recurrent styes, due to scaly debris blocking and disrupting glands, causing inflammation and infection. Additionally, makeup, especially that which is contaminated with bacteria, is also a common cause for infected styes.

Styes are often self-limiting and can drain and resolve without any treatment. Antibiotics generally do not have a role despite the involvement of bacterium in their aetiology. If they persist, then conservative treatment with hot compress to the affected eyelid for 5–10 minutes, four times a day until drained is advocated. If the stye is particularly painful, then epilation of the eyelash from the infected follicle may assist drainage and provide pain relief. Topical antibiotics are discouraged. However, they can be considered if there is associated conjunctivitis and mucopurulent discharge (NICE, 2019b). Patients can be referred to secondary care if a stye does not resolve despite conservative measures or enlarges and becomes more painful.

Chalazion

The term chalazion refers to ‘hail stone’ in Greek, which resembles the localised swelling in the eyelid margin. This is differentiated from a stye as it is completely painless and does not share the red and angry pustular appearance. Sometimes, styes that persist, can transform into a chalazion once the infection and inflammation has settled. Chalazia often occur due to blockage of the meibomian glands and are therefore also known as meibomian cysts (Jordan and Bier, 2019). It is an asymptomatic problem, but often patients present as a result of uncertainty regarding the swelling.

The diagnosis is based on typicality of appearance, with examination revealing a smooth non-tender swelling on the underside of the eyelid visible on lid inversion. Chalazia can be managed conservatively in general practice, and patients can be reassured that they are self-limiting and rarely cause complications. First-line management is application of hot compresses followed immediately by lid massages to help express the cyst contents and encourage drainage. Topical antibiotics are discouraged for chalazion, as they have no therapeutic benefit. If the chalazion persists beyond 4 weeks, watchful waiting in asymptomatic cases or referral to ophthalmology for further management can be considered (NICE, 2019b).

Preseptal cellulitis

Preseptal cellulitis is also known as periorbital cellulitis and is an acute infection of the eyelids and the surrounding soft tissues in the anterior compartment of the eye. It is crucial to make a distinction between preseptal cellulitis and orbital cellulitis, due to the clinical implications. Preseptal cellulitis is a less severe infection; rarely progressing to more serious complications, whereas orbital cellulitis can be sight-threatening and if untreated can cause sepsis and death.

Familiarity with the basic anatomy is therefore fundamental to understanding the clinical presentation, predict potential complications, and manage the condition safely and efficiently. The orbit is divided into an anterior and posterior compartment demarcated by a fibrous membrane called the orbital septum. This septum extends from the orbital rims and covers the eyelids. In the upper eyelid the orbital septum fuses with the tendon of the levator palpebrae superioris, which elevates the upper lid, and to the tarsal plate in the lower eyelid. When the eye is closed the entire opening of the eye is covered by the orbital septum (Lee and Yen, 2011). Infection anterior to this septum is termed preseptal cellulitis and posterior to this, orbital cellulitis (Fig. 3).

Figure 3.

Highlighting the anatomical position of Presptal and Orbital cellulitis.

Preseptal cellulitis is commonly caused by a bacterial infection and can start focally from the eyelids following skin breaks from trauma, foreign bodies or insect bites. It can also spread from neighbouring infection such as a style, dacryocystitis, impetigo and sinusitis, the latter being one of the most common causes (Gappy and Archer, 2020). The ethmoid sinuses are especially implicated, as they share vessels and nerves with the orbit. Hameatogenous spread is also possible following upper respiratory tract or middle ear infections.

S.aureus and Streptococcus pneumoniae are common pathogens implicated in this infection. Historically, Haemophilus influenzae was the typical pathogen in children until the advent of routine immunisation (Gappy C, Archer SM and Barza M, 2020).

Preseptal cellulitis is a clinical diagnosis and patients present with characteristic unilateral erythema around the eye, ocular pain and swelling. Chemosis (conjunctival swelling) may occur in severe cases. Orbital cellulitis may clinically appear in similar fashion, but due to swelling of the extraocular muscles, additional signs may be present including painful eye movements, proptosis, ophthalmoplegia and diplopia; these are key distinguishing factors (Table 2).

Table 2.

Features distinguishing preseptal from orbital cellulitis.

Symptoms	Preseptal cellulitis	Orbital cellulitis
Pain	Present	Present
Erythema	Present	Present
Eyelid oedema	Present	Present
Chemosis	Absent (unless severe)	Present
Visual acuity	Intact (if reduced often secondary to lid oedema)	Reduced
Pupils	Intact	May be affected
Eye movements	Intact	Affected
Proptosis	Absent	Present

Often, preseptal cellulitis can be managed in primary care providing there are no signs of systemic upset and the patient can be followed up closely by the GP. Antibiotics are the gold standard and treatment is empirically started and targeted towards common causative organisms. Where there is isolated eyelid involvement only, oral Co-amoxiclav (Clindamycin if penicillin allergic) is the antibiotic of choice (Ball et al., 2017). If there is any evidence of systemic upset or any signs of orbital cellulitis on examination, then the patient must be urgently admitted to the hospital.

Xanthelasma

Xanthelasma are yellow cholesterol-filled plaques that often present on the inner canthus of the eye and are more likely to affect the upper lids. They occur more frequently in middle and older age patients. Patients presenting with these are screened with full lipid profile tests, as they may indicate an underlying dyslipideamia. These findings in younger patients should prompt investigation for inherited conditions such as familial hypercholesterolaemia.

Xanthelasma are completely asymptomatic, and patients often present because of cosmetic concerns. They do not require any direct treatment and management should be focused on treating the underlying dyslipidemia and assessing cardiovascular risks. Diet modification and lipid- lowering treatments may induce regression but this cannot be guaranteed (Jonsson and Sigfiisson, 2017). Surgical excision can be performed for cosmetic purposes, but recurrence is common.

Entropion

Entropion is a condition whereby the eyelids turn inwards causing the eyelashes and lids to rub against the ocular surface, resulting in pain and irritation. An entropion is three times more likely to be bilateral and its prevalence is highest in older patients: 0.9% in those aged 60–69, 2.1% in those aged 70–79, and 7.6% in those aged >80 years in one study (Damasceno et al., 2011). With an ageing eye there is loss of horizontal lid support, tendon laxity, and tarsal and orbital fat atrophy leading to enophthalmos. Weakening of these supports leads to the antagonistic orbicularis oculi muscle overriding and causing inversion of the lid i.e. involutional entropion.

Patients often present with a foreign body sensation, red sore eyes, tearing due to paradoxical dry eye and discharge. Dry eye syndrome is a consequence of entropion and is present in 72.1% of patients (Damasceno et al., 2011). A persistent entropion can lead to complications of the cornea including abrasions, thinning, neovascularisation, ulcers and perforation.

As an entropion is a progressive condition, patients should be referred to ophthalmology for definitive surgical treatment. Alternatively, patients may also be managed conservatively where there is a patient preference, or where they may not be suitable candidates for surgical options (e.g. frailty, comorbidity, etc.). Conservative measures can include taping of the lower lid to the cheek and providing rigorous lubrication to the eye with drops and ointments to prevent the ocular surface drying out. This is only of temporary benefit for symptom relief.

Ectropion

In contrast, an ectropion is where the eyelid turns outwards leaving the ocular surface exposed with inadequate lubrication, leading to a dry and irritated eye. This typically affects the lower lid and is also more common in older patients with prevalence being as high as 2% (Ozgur et al., 2019).

The aetiology of ectropions is commonly involutional and caused by laxity of the horizontal tendon supports and dis-insertion of the lower lid retractors which assist the active closure of the eyelid. This process is accelerated by repetitive eye rubbing. Paralytic ectropions can occur as a result of facial nerve palsy. Additionally, mechanical ectropion can be caused by previous surgery, dermatological conditions affecting the eyelids (e.g. lid eczema), or growths (tumours) of the lower eyelids that may have a gravitational effect pulling down the lid and exposing the ocular surface (Ozgur et al., 2019). A detailed history and examination is therefore imperative to determine the underlying cause and ectropion should not be simply attributed to ageing.

Patients present with an obvious abnormal positioning of the eyelid and report symptoms of tearing (due to paradoxical dry eye), grittiness, irritation and a foreign body sensation. The eye can often be injected and red with discharge. Ectropion are a spectrum from minimal to severe malpositioning of the eyelids requiring forceful blinking to bring the eyelids back to a neutral position.

All patients with ectropion should be offered conservative management before being referred to secondary care. Initial management should focus on ensuring maximal lubrication to the ocular surface with eye drops, gels and ointments to relieve symptoms and avoid further damage through drying out. Treatment also focuses on addressing the underlying cause. Where there is chronic lid eczema, this can be managed in primary care with emollients and topical steroids to reduce further mechanical trauma and progression through rubbing of the eye. Definitive treatment is essentially surgical, especially where there are growths/tumours present. A holistic assessment in primary care should help determine whether surgery would be in the best interest of a patient, particularly with higher prevalence of this condition in older age groups.

Sebaceous cyst

Sebaceous cysts are one of the most common types of cysts in the skin and can also present on the eyelid. Sebaceous cysts are essentially benign solitary subepidermal nodules that grow slowly and present more frequently on the upper eyelid. They can be either congenital or occur secondary to trauma or surgery. They are often asymptomatic, but can get infected and inflamed causing enlargement and pain, due to the inflammatory reaction.

Sebaceous cysts can often be managed conservatively in primary care and can be left alone. If they become infected, empirical antibiotics which cover common commensals can be commenced (e.g. Flucloxacillin or Erythromycin if penicillin allergic). If they become repeatedly infected or increase in size impeding vision, surgical excision can be considered.

Basal cell carcinoma

Basal cell carcinoma (BCC) is a non-melanoma-type skin cancer (NMSC), also known as a rodent ulcer. It is more prevalent in fair-skinned individuals with a history of prolonged sun exposure. It accounts for up to 80% of all skin cancers in the UK and 85–90% of all eyelid malignancies, two-thirds of which involve the lower eyelid margins (Margo and Waltz, 1993). They often present as a painless pearly nodule or bump with associated telangiectasia. BCCs are locally invasive and rarely metastasise. Nevertheless, although BCCs are slow-growing, they should still be referred under the urgent 2-week pathway if they are located on the face - as delay can have a significant impact due to site and/or size of the lesion.

Diagnosis is suspected on history and examination, but requires referral for histopathological confirmation with biopsy/excision (NICE, 2016). Although these cancers typically only cause local symptoms, if left untreated can progress and invade deeper tissues and bone.

Squamous cell carcinoma

Squamous cell carcinoma is the second most common type of skin cancer in the UK accounting for 20% of all NMSCs (Alam and Ratner, 2001). The single most important risk factor for this is ultraviolet sunlight exposure and therefore more likely to occur on sun-exposed areas of the body (Brash et al., 1991). This is a much more aggressive tumour and can metastasise. Most eyelid SCCs are found on the lower lid with a tendency for the lid margin. They can develop de novo or from predisposing skin conditions such as actinic keratosis.

They can vary in their appearance but commonly present as a sore crusted lesion with an inflamed base that can resemble an ulcer which can bleed. Diagnosis is based on their clinical appearance and history of risk factors. All patients must be referred on a fast-track 2-week pathway for diagnosis with biopsy by an ophthalmologist (NICE, 2016).

KEY POINTS

Eyelid symptoms in adults are a common presentation to general practice

Detailed history and close inspection of the eyelids can help with more accurate diagnosis of the underlying lid problem

Accurate diagnosis and correct management can help prevent longer term and peristent eye problems

Lid hygiene is essential for patients with blepharitis and dry eye symptoms

Where characteristic features of orbital cellulitis are present, urgent admission for assessment by an ophthalmologist is required

Refer suspicious lesions indicative of cancer urgently on the 2-week fast-track referral pathway

Footnotes

Acknowledgment

We would like to thank Dr Kunal Chawathey for his help with the writing of this article under the InnovAiT ‘buddy’ scheme.

ORCID iD

Dr Tahir Shaheen

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