A perforated septum is a hole in the thin wall of cartilage and tissue that divides your two nostrils. From the outside, small perforations often look like nothing at all. The visible signs depend entirely on where the hole is and how large it has grown. What you’re most likely to notice, whether looking in a mirror or examining someone else’s nose, is crusting, dried blood, or a visible opening when you tilt the head back and shine a light into the nostrils.
What You See Inside the Nose
If you look into the nostrils with a flashlight or use a mirror, a septal perforation appears as an actual hole through the dividing wall between the two nasal passages. In other words, you can see from one nostril straight through to the other. The hole may be round or oval, and the edges can range from smooth and lined with pinkish mucous membrane to raw, inflamed, and irregular.
The most common visual clue is heavy crusting around the edges of the hole. Dried blood and thick, yellowish or greenish scabs tend to collect along the rim of the perforation, sometimes obscuring the hole itself. Clinicians routinely remove all crusting before they can even see the full extent of the damage. If you’re looking in a mirror and notice persistent scabbing deep inside one or both nostrils, that buildup may be masking a perforation underneath.
Smaller perforations, especially those located further back in the nose, can be impossible to see without a medical scope. Larger ones closer to the front of the nose are easier to spot, sometimes visible just by lifting the nasal tip and looking inside.
How Perforations Are Sized
Perforations are classified by diameter. Small ones measure less than 1 centimeter across, medium ones fall between 1 and 2 centimeters, and large perforations exceed 2 centimeters. An alternative system classifies them by how much of the septum’s total height they consume: less than a third (roughly 0 to 8 millimeters) counts as small, one third to two thirds (9 to 18 millimeters) as medium, and anything beyond two thirds as large.
A small perforation may look like a pinhole or a pencil eraser-sized opening. A large one can destroy most of the septum, leaving very little tissue between the two nasal cavities. The size matters not just for symptoms but for what the nose looks like from the outside, since bigger perforations are more likely to weaken the structural support of the nose itself.
What Changes on the Outside of the Nose
Small perforations rarely change the external appearance of your nose. You might have one for years without anyone, including you, noticing a visual difference. The signs are internal: whistling when you breathe, crusting, nosebleeds, and a feeling of nasal obstruction.
Larger perforations are a different story. When enough cartilage is destroyed, the nasal bridge loses its structural support and can begin to collapse inward. This is called saddle nose deformity, named for the sunken, saddle-like dip it creates along the bridge. The middle portion of the nose sags, creating a visible depression. Over time, the concavity can become more pronounced. Other external signs include a turned-up nasal tip and a horizontal crease across the lower portion of the nose. The overall profile of the nose shortens and flattens in a way that’s distinct from a naturally wide or flat nasal bridge.
This kind of external collapse doesn’t happen overnight. It develops gradually as the perforation enlarges or as weakened cartilage gives way. Not every perforation leads to saddle nose, but it’s one of the more recognizable visual consequences of a large, untreated one.
Signs That Often Accompany the Hole
Beyond the hole itself, several visual and physical signs tend to cluster together:
- Crusting and scabbing along the perforation’s edges, often mistaken for a stubborn cold or allergies
- Dried blood inside the nostrils, especially in the morning
- Redness and inflammation of the surrounding nasal lining, which may look raw or eroded
- Asymmetry inside the nostrils if the hole is off-center or if one side has more tissue loss
The tissue surrounding the perforation can look pale, thin, and fragile, or it can appear angry and inflamed depending on the cause. Perforations caused by chronic irritation (such as repeated nose picking or drug use) often have rougher, more irregular edges than surgical perforations, which tend to be cleaner and more defined.
How to Check at Home
You can do a basic check with a flashlight and a mirror. Tilt your head back slightly, lift the tip of your nose with a finger, and shine a light into one nostril. If there’s a perforation near the front of the septum, you may see light passing through to the other side, or you may spot crusting clinging to an area that looks eroded or open. Closing one nostril and breathing through the other can sometimes produce a whistling sound if a small perforation is present, which is another clue even when you can’t see the hole directly.
Perforations located deeper in the nose won’t be visible this way. If you have persistent symptoms like one-sided crusting, recurrent nosebleeds, or a whistling noise when breathing, an ENT specialist can use a thin camera to examine the full length of the septum and identify holes that a mirror check would miss.