The caruncle is the small pink bump in the inner corner of each eye, right where the upper and lower lids meet.1Kenhub. Lacrimal caruncle It looks like part of the white of the eye, but it is really a patch of moist, modified skin, which is why it can do things the rest of the eye surface can’t. That skin-like makeup explains both its quiet daily job of cleaning the eye and why it can occasionally develop its own bumps and spots.2PubMed. Lesions of the caruncle: a description of 42 cases and a review of the literature
Where the Caruncle Sits and What It’s Made Of
The caruncle sits inside a small triangular space in the inner corner where tears pool before draining.3Kenhub. Lacrimal caruncle It is reddish and slightly lumpy.4Kenhub. Lacrimal caruncle
To find yours, pull the lower lid gently down and look at the corner nearest your nose. The caruncle is the rounded pink mound there, and it should look similar on both sides. Size and colour vary from person to person, so slight differences are common. It can also look redder when you’re tired or have been rubbing your eyes.
Unlike the outer skin of your face, its surface has no tough, dry outer layer and resembles the clear lining of the eye.5PubMed. Lacrimal caruncle Underneath, though, it holds things normally found in skin: hair follicles, oil glands and sweat glands.6PubMed. Lacrimal caruncle It also contains extra tear-making tissue, a small backup to the main tear gland.7International Medical Case Reports Journal. Papilloma and sebaceous gland hyperplasia of the lacrimal caruncle: a case report
The caruncle is not the same as the white of the eye. The white is a tough, smooth, mostly pale layer under a thin clear membrane. The caruncle is a raised, fleshy, pinkish mound tucked between the lids, not part of the rounded surface of the eyeball.
It is also easy to confuse with the drainage system. The tear drainage holes are tiny dots on the lid edges near the corner, not on the caruncle. The caruncle sits beside them in the tear pool and doesn’t drain anything itself.
What the Caruncle Does Every Day
Fine hairs on the caruncle help catch and remove dust and small particles.8Kenhub. Lacrimal caruncle These hairs may also help spread the tear film evenly over the eye.9Kenhub. Lacrimal caruncle
Dust, loose lashes and bits of mucus ride along in the tear flow and collect in the tear pool beside the caruncle, which is why you often find a speck of grit there after your eye waters. You can usually lift it out with a clean fingertip or a rinse.
The caruncle also contributes to morning crust. Its modified sweat glands make a thick secretion that adds to the grainy material around the lids after sleep.10Kenhub. Lacrimal caruncle We don’t blink while asleep, so discharge collects in the eye corners and along the lashes.11American Academy of Ophthalmology. What Is Sleep Crust? During the day, blinking and tears wash this material away before it can stick.12University of Utah Health. Is That Morning ‘Eye Gunk’ Normal?13University of Utah Health. Is That Morning ‘Eye Gunk’ Normal?
The crust is a mix of dried tears, oil, mucus, shed skin cells and a little debris. The caruncle’s secretions are one ingredient among several, since the lids and the eye surface contribute too. That mix is why crust can look pale, grainy or slightly stringy and still be completely normal.
Normal crust is a small amount of dry or slightly sticky material in the corners. It wipes away easily and doesn’t return all day. Lots of thick yellow or green discharge, or lids glued shut in the morning, suggests infection. If discharge comes with pain, redness and blurred vision, see a doctor.
To clean the corner safely, wash your hands first, then use clean fingers or a warm damp cloth and wipe from the inner corner outward. Don’t pick at it with your nails, which can scratch the eye surface. If one eye looks infected, use a separate part of the cloth for each eye so you don’t carry germs across.
Hairs, Redness and Other Normal Quirks
Having hairs and glands in the caruncle can be quite normal.14American Academy of Ophthalmology. Is it normal for hair to grow outward from the lacrimal caruncle? Occasionally a hair grows toward the eye and rubs it, which can cause irritation.15PubMed. Lacrimal caruncle
A single fine hair that you only notice in a mirror and that causes no symptoms is usually a harmless variation, and it can be left alone. A hair that points toward the eye can leave a gritty feeling, watering or redness in the inner corner, especially after blinking. If it pokes the eye, an eye doctor can remove it safely. Don’t pluck it yourself with tweezers near the eyeball. If those symptoms keep returning, an eye doctor can check whether a hair is the cause, since other problems, such as an eyelash growing inward, feel much the same.
The caruncle can also look redder or puffier on some days. Rubbing your eyes pushes blood into its surface, and lack of sleep or dry air can make the area look more inflamed. Mild redness that settles within a day is usually nothing to worry about.
Why the Caruncle Gets Itchy With Allergies
In eye allergies, the inner corner where the caruncle sits is often the site of the most intense itch.16Eyes On Norbeck. Eye Allergies Pollen and other allergens irritate it, making it swollen and inflamed.17Eyes On Norbeck. Eye Allergies Allergens and the substances the eye makes to fight them also accumulate in that corner.18Eyes On Norbeck. Eye Allergies
The swelling is hard to miss. During an allergic reaction, cells in the eye release histamine, which makes small blood vessels leak fluid and the tissue puff up. The caruncle is soft and loose, so the swelling shows up easily as a puffy pink or red lump. The same reaction makes the white of the eye look pink and the lids puffy, so the corner is rarely the only affected spot.
Rubbing feels good for a moment, but it triggers more histamine release, which then increases the itch afterward. It also moves pollen and dust from your fingers and lids into the corner, and rubbing hard can irritate the eye surface.
A cool compress can calm the swelling, and rinsing with lubricating eye drops can flush allergens out. Over-the-counter antihistamine eye drops help many people; a pharmacist can point you to one. Washing your face after being outdoors removes pollen from the lashes.
Allergy and infection can look alike at first. Allergy usually affects both eyes and is mostly itchy with watery discharge, and flares follow seasons or exposures like pets and dust. Infection more often brings sticky yellow discharge and soreness.
Is the Caruncle a Leftover Third Eyelid
Many animals have a clear third eyelid that sweeps across the eye from the inner corner to protect and moisten it while they can still see.19Wikipedia. Nictitating membrane Frogs, many birds, sharks, and some mammals such as cats, seals and polar bears have a full one.20Wikipedia. Nictitating membrane
In many mammals only a small leftover piece remains in the eye corner.21Wikipedia. Nictitating membrane In humans, the small pink fold just beside the caruncle shows signs of coming from that third eyelid.22PubMed. The structure of the human semilunar plica at different stages of its development–a morphological and morphometric study So the caruncle itself isn’t the leftover; it is the skin-like mound next to it. Together they still do some of the third eyelid’s cleaning work in the corner.
You can see the fold yourself. Look sideways toward your ear while watching the inner corner, and a thin curved pink fold appears between the caruncle and the white of the eye. It stretches and slackens as your eye moves, which is normal.
The human fold cannot sweep across the eye. Our eyes are protected by well-developed lids, and tears and blinking handle most cleaning on their own. Scientists treat the fold as a structure that shrank because it was less needed, which is a reasonable view rather than a proven timeline.
Bumps and Spots on the Caruncle and When to Get Them Checked
Because the caruncle mixes skin, eye lining and tear tissue, it can develop growths seen in any of those tissues.23PubMed. Lesions of the caruncle: a description of 42 cases and a review of the literature Benign lumps are more common there than cancers.24PubMed Central. Clinical profile, histopathology, and management of caruncular lesions; a systematic review Common harmless ones include moles, wart-like papillomas, and pyogenic granulomas, red bumps that bleed easily.25PubMed Central. Clinical profile, histopathology, and management of caruncular lesions; a systematic review
A mole on the caruncle is a brown or tan spot that can be flat or raised and may darken a bit around puberty or pregnancy. A papilloma looks like a small pink growth with a rough, cauliflower-like surface and is often caused by a wart virus. A pyogenic granuloma is a soft red or pink bump that grows over weeks and bleeds with a light touch. It often follows an injury, surgery or irritation, and the name is misleading since it is neither an infection nor a true granuloma. A caruncle cyst is a smooth, fluid-filled bump that can form when a gland duct blocks. It is typically painless and may stay unchanged for years, and some can be drained or removed if they bother you or distort the corner.
Signs of cancer include fast growth, new pigment, an ulcerated surface and bleeding.26PubMed Central. Malignant lesions of the caruncle Increasing darkness can point to melanoma, a yellow look to an oil-gland cancer, and a salmon-pink colour to a lymphoma-type growth.27PubMed Central. Malignant lesions of the caruncle Skin cancers such as basal cell carcinoma can rarely start on the caruncle.28PubMed. Lacrimal caruncle primary basal cell carcinoma: case report and review Any changing lump there deserves an eye exam rather than waiting.
A check-up usually starts with the doctor examining the bump under a magnifying slit lamp. They may photograph it to track changes over months, and a suspicious lump can be removed and examined under a microscope. Taking your own phone photos every few weeks can help show any change, but it doesn’t replace an exam.
In rare cases, lumps on both caruncles have been an early sign of a body-wide blood-vessel inflammation called vasculitis.29PubMed Central. Bilateral lacrimal caruncle lesions Bumps in both eyes alongside unexplained symptoms like sinus trouble or fatigue are worth mentioning to a doctor.
The Caruncle in Cosmetic Eye Surgery
Inner-corner eyelid surgery releases the skin fold over the corner to show more of the eye.30Plasticsurgery Key. Epicanthoplasty and Aesthetic Lateral Canthoplasty That fold is the epicanthal fold, a fold of skin from the upper lid that covers the inner corner and part of the caruncle. It is a normal feature in many people, particularly those of East Asian descent, and is common in young children of all backgrounds. Having one is not a defect, and many people choose to keep it.
Surgeons find a fold looks most natural when it covers less than half the caruncle.31Plasticsurgery Key. Epicanthoplasty and Aesthetic Lateral Canthoplasty Showing about 80 to 90 percent of the caruncle is generally considered most pleasing.32Plasticsurgery Key. Epicanthoplasty and Aesthetic Lateral Canthoplasty The operation is often done with double eyelid surgery, because the two changes together affect the look of the whole eye. The goal is a corner that looks balanced with the person’s face, not a fixed amount of exposure for everyone.
Before inner-corner surgery, ask how much of the caruncle will show afterward, since overexposing it can make the corner look unnaturally pink. Changes to the inner corner are hard to reverse, so choose a surgeon experienced in eyelid procedures.