| Lacrimal caruncle | |
|---|---|
 Front of left eye with eyelids separated. Caruncula visible and labeled at left. | |
| Details | |
| System | eye |
| Identifiers | |
| Latin | caruncula lacrimalis |
| TA98 | A15.2.07.049 |
| TA2 | 6844 |
| FMA | 77672 |
| Anatomical terminology | |
The lacrimal caruncle, or caruncula lacrimalis, is the small, pink, globular nodule at the inner corner (the medial canthus) of the eye. [1] It consists of tissue types of neighbouring eye structures. It may suffer from lesions and allergic inflammation.
The lacrimal caruncle is found at the medial canthus of the eye. [1] It consists of skin, hair follicles, sebaceous glands, sweat glands, accessory lacrimal tissue and other tissues that are present in the skin and accessory lacrimal glands. [1] [2] Its non-keratinized epithelium resembles the conjunctival epithelium. [2]
The lacrimal caruncle may have a lesion. [3] This can have any one of a number of causes, which may be difficult to diagnose. [3] Cancer is a rare cause. [3] [4] These lesions include papillomas and oncocytomas. [4]
With ocular allergies, the lacrimal caruncle and the plica semilunaris of the conjunctiva may be inflamed and pruritic (itchy) due to histamine release in the tissue and tear film.
Sweat glands and oil glands are contained in the caruncle of the eye (lacrimal caruncle in medial canthus). As with all oil glands, lacrimal caruncles can become clogged, causing a pimple, whitehead, or pustule beneath the skin. Clogged oil and sweat glands in the caruncle can affect tear ducts. Treatment for dry eyes due to clogged glands includes refraining from rubbing the eyes and rinsing the eyes with clear water frequently during the day, either with clean hands or a spray faucet. Additionally, one can use a warm damp cloth on the eye, which will help the clogged pore to open up and release some pressure. Anti-bacterial eye drops may also be prescribed. If the pustules enlarge, an oral antibiotic may be prescribed. If lesions such as cysts form, they must be surgically drained; this operation is rarely necessary. [5] If it affects the tear sac it may be dacryocystitis.
A sebaceous gland or oil gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals. In humans, sebaceous glands occur in the greatest number on the face and scalp, but also on all parts of the skin except the palms of the hands and soles of the feet. In the eyelids, meibomian glands, also called tarsal glands, are a type of sebaceous gland that secrete a special type of sebum into tears. Surrounding the female nipple, areolar glands are specialized sebaceous glands for lubricating the nipple. Fordyce spots are benign, visible, sebaceous glands found usually on the lips, gums and inner cheeks, and genitals.
Eye surgery, also known as ophthalmic surgery or ocular surgery, is surgery performed on the eye or its adnexa. Eye surgery is part of ophthalmology and is performed by an ophthalmologist or eye surgeon. The eye is a fragile organ, and requires due care before, during, and after a surgical procedure to minimize or prevent further damage. An eye surgeon is responsible for selecting the appropriate surgical procedure for the patient, and for taking the necessary safety precautions. Mentions of eye surgery can be found in several ancient texts dating back as early as 1800 BC, with cataract treatment starting in the fifth century BC. It continues to be a widely practiced class of surgery, with various techniques having been developed for treating eye problems.
A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment.
Blepharitis, sometimes known as "granulated eyelids," is one of the most common ocular conditions characterized by inflammation, scaling, reddening, and crusting of the eyelid. This condition may also cause swelling, burning, itching, or a grainy sensation when introducing foreign objects or substances to the eye. Although blepharitis by itself is not sight-threatening, it can lead to permanent alterations of the eyelid margin. The primary cause is bacteria and inflammation from congested meibomian oil glands at the base of each eyelash. Other conditions may give rise to blepharitis, whether they be infectious or noninfectious, including, but not limited to, bacterial infections or allergies.
An eyelid is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily. "Palpebral" means relating to the eyelids. Its key function is to regularly spread the tears and other secretions on the eye surface to keep it moist, since the cornea must be continuously moist. They keep the eyes from drying out when asleep. Moreover, the blink reflex protects the eye from foreign bodies. A set of specialized hairs known as lashes grow from the upper and lower eyelid margins to further protect the eye from dust and debris.
A chalazion or meibomian cyst is a cyst in the eyelid usually due to a blocked meibomian gland, typically in the middle of the eyelid, red, and not painful. They tend to come on gradually over a few weeks.
The nasolacrimal duct carries tears from the lacrimal sac of the eye into the nasal cavity. The duct begins in the eye socket between the maxillary and lacrimal bones, from where it passes downwards and backwards. The opening of the nasolacrimal duct into the inferior nasal meatus of the nasal cavity is partially covered by a mucosal fold.
An epidermoid cyst or epidermal inclusion cyst is a benign cyst usually found on the skin. The cyst develops out of ectodermal tissue. Histologically, it is made of a thin layer of squamous epithelium.
A milium, also called a milk spot or an oil seed, is a clog of the eccrine sweat gland. It is a keratin-filled cyst that may appear just under the epidermis or on the roof of the mouth. Milia are commonly associated with newborn babies, but may appear on people of any age. They are usually found around the nose and eyes, and sometimes on the genitalia, often mistaken by those affected as warts or other sexually transmitted diseases. Milia can also be confused with stubborn whiteheads.
The orbicularis oculi is a muscle in the face that closes the eyelids. It arises from the nasal part of the frontal bone, from the frontal process of the maxilla in front of the lacrimal groove, and from the anterior surface and borders of a short fibrous band, the medial palpebral ligament.
The oral mucosa is the mucous membrane lining the inside of the mouth. It comprises stratified squamous epithelium, termed "oral epithelium", and an underlying connective tissue termed lamina propria. The oral cavity has sometimes been described as a mirror that reflects the health of the individual. Changes indicative of disease are seen as alterations in the oral mucosa lining the mouth, which can reveal systemic conditions, such as diabetes or vitamin deficiency, or the local effects of chronic tobacco or alcohol use. The oral mucosa tends to heal faster and with less scar formation compared to the skin. The underlying mechanism remains unknown, but research suggests that extracellular vesicles might be involved.
Warthin's tumor, also known as papillary cystadenoma lymphomatosum, is a benign cystic tumor of the salivary glands containing abundant lymphocytes and germinal centers. It is named for pathologist Aldred Scott Warthin, who described two cases in 1929.
Fordyce spots are harmless and painless visible sebaceous glands typically appearing as white/yellow small bumps or spots on the inside of lips or cheeks, gums, or genitalia. They are common, and are present in around 80% of adults. Treatment is generally not required and attempts to remove them typically result in pain and scarring.
The lacrimal sac or lachrymal sac is the upper dilated end of the nasolacrimal duct, and is lodged in a deep groove formed by the lacrimal bone and frontal process of the maxilla. It connects the lacrimal canaliculi, which drain tears from the eye's surface, and the nasolacrimal duct, which conveys this fluid into the nasal cavity. Lacrimal sac occlusion leads to dacryocystitis.
The plica semilunaris is a small fold of bulbar conjunctiva on the medial canthus of the eye. It functions during movement of the eye, to help maintain tear drainage via the lacrimal lake, and to permit greater rotation of the globe, for without the plica the conjunctiva would attach directly to the eyeball, restricting movement. It is the vestigial remnant of the nictitating membrane which is drawn across the eye for protection, and is present in other animals such as birds, reptiles, and fish, but is rare in mammals, mainly found in monotremes and marsupials. Its associated muscles are also vestigial. It is loose, thus eye movements are not restricted by it. Only one species of primate, the Calabar angwantibo, is known to have a functioning nictitating membrane.
Oculoplastics, or oculoplastic surgery, includes a wide variety of surgical procedures that deal with the orbit, eyelids, tear ducts, and the face. It also deals with the reconstruction of the eye and associated structures.
Hidrocystoma is an adenoma of the sweat glands.
Salivary gland tumours, also known as mucous gland adenomas or neoplasms, are tumours that form in the tissues of salivary glands. The salivary glands are classified as major or minor. The major salivary glands consist of the parotid, submandibular, and sublingual glands. The minor salivary glands consist of 800 to 1000 small mucus-secreting glands located throughout the lining of the oral cavity. Patients with these types of tumours may be asymptomatic.
Syringocystadenoma papilliferum is a rare non-malignant adnexal neoplasm that develops from apocrine or eccrine sweat glands and can be identified histologically by cystic, papillary, and ductal invaginations into the dermis lined by double-layered outer cuboidal and luminal high columnar epithelium and connected to the epidermis.
The accessory visual structures are the protecting and supporting structures (adnexa) of the eye, including the eyebrow, eyelids, and lacrimal apparatus. The eyebrows, eyelids, eyelashes, lacrimal gland and drainage apparatus all play a crucial role with regards to globe protection, lubrication, and minimizing the risk of ocular infection. The adnexal structures also help to keep the cornea moist and clean.
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