The pathology of the eyelids is vast. Many changes may be age-related, while others may be associated with inflammatory, infectious, traumatic agents or even tumours.
Among the anatomical alterations we can find ptosis, entropion, ectropionand eyelid retraction.
- Ptosis corresponds to a change in the position of the upper eyelid, which is drooping, and may affect the visual axis. It has different causes - congenital, senile, traumatic, associated to systemic or autoimmune pathologies, such as myasthenia gravis, among others.
- Entropion is a change of the eyelid that curls inwards (usually the lower eyelid) causing lesions on the ocular surface due to constant rubbing of the eyelashes against the surface.
- In ectropion the lower eyelid turns outwards, exposing the palpebral conjunctiva, leaving the eye unprotected and with difficulties in lubrication. It can be related to age due to loss of tonicity of the eyelid muscle (the orbicular), trauma, tumours. Since in this case the eyelid does not close the eyelid crevice completely and correctly, there is a deficit of lubrication, with dystrophic and inflammatory changes both in the eyelid and on the ocular surface.
Another common pathology that affects the eyelid is cysts with or without inflammation, which include chalazia and hordeolus (aka pinkeye or pinkeye).
Trichiasisand dystikiasisare pathologies that affect the eyelashes, the former growing inwards and the latter growing in an abnormal location. In both cases there can be friction of the lashes on the ocular surface, causing uncomfortable and potentially damaging corneal lesions.
The tears produced by the main lacrimal gland, located in the lacrimal fossa, on the superolateral wall of the orbit and are spread by the movements of the eyelid (the blink) on the ocular surface. Subsequently they pass to the lacrimal points, from there to the lacrimal canaliculi and to the lacrimal sac, where they accumulate. They are later finally eliminated through the nasal tear duct into the nasal cavities. The tear consists of water, minerals, proteins, lipids and antibacterial enzymes (lysozyme, destroys the cell wall of many bacteria). Any alteration in the tear production/drainage balance will have repercussions on the comfort and health of the ocular surface.
Alterations in the lacrimal ducts cause epiphora (tearing), when there is difficulty or even impediment in draining the nasal cavities, caused by inflammatory or mechanical processes.
The impossibility of draining the lacrimal sac due to occlusion of the nasal tear duct leads to an accumulation of tears and bacteria carried by them. The bacterial proliferation ends up causing an acute and very painful infection of the sac, the dacryocystitis.
Dacryocystitis is an infection of the lacrimal sac. It can form an abscess, requiring systemic antibiotic therapy, which does not always resolve and sometimes has to be drained by puncture. When they are very repeated, they sometimes end with the definitive ablation of the lacrimal sac(dacryocystectomy). When there is an obstruction of the nasal tear duct, with an epiphora, it is necessary to perform a surgery, nowadays simplified by the use of a laser, which re-establishes the passage, avoiding the obstruction(dacrocistorhinostomy).
Oculoplastic surgery also allows for the assessment and treatment of situations in which it is necessary to empty or remove the eyeball (evisceration/ enucleation) due to atrophy, tumours or severe chronic pain (e.g. neovascular glaucoma ) in eyes without useful vision, and the respective aesthetic reconstruction.