Doctor, First-Degree Specialist Be Thu Thuy, from the Department of Aesthetics at Tam Anh General Hospital Hanoi, states that filler injection is a minimally invasive cosmetic procedure that quickly and safely reduces depressions, sculpts contours, and rejuvenates the face. However, this method carries potential risks, the most severe of which is tissue necrosis. This can lead to scarring, cosmetic disfigurement, and even functional impairment of vital facial areas.

Doctor Thuy explains that necrosis primarily occurs when filler inadvertently enters a blood vessel or compresses it, obstructing blood flow that supplies oxygen and nutrients to the tissue. This happens when the filler is injected into the wrong vessel or when an excessive amount of filler is injected, causing vessel compression. Areas with complex vascular systems, such as the nose, nasolabial folds, lips, and periorbital region, are particularly susceptible to this risk.

Incorrect injection depth, aggressive needle use, rapid injection techniques, lack of aspiration checks, and poor control over needle direction also increase the risk of vascular occlusion. Other contributing factors include using poor-quality filler, undergoing procedures at unqualified facilities, performing injections in non-sterile conditions, or by individuals unfamiliar with facial anatomy. In such cases, patients may experience the following symptoms.

Reduced skin sensation

This is an early sign that filler has entered a blood vessel, impeding blood circulation, or compressing a nerve in the injected area. Patients may experience numbness, tingling, or a noticeable reduction in sensation when touching the treated area compared to surrounding skin.

Persistent swelling and redness at the injection site

Swelling and redness are normal reactions after filler injections, typically lasting for the first 24-48 hours. However, if the skin remains significantly swollen, red, and hot, without improvement after two to three days, it signals an abnormality. This redness may spread along the blood vessels and gradually turn purplish due to tissue oxygen deprivation, indicating potential necrosis.

Severe, persistent pain

Doctor Thuy notes that properly performed filler injections only cause mild stinging and slight tightness for a short duration. However, if pain gradually intensifies and throbs with each pulse after injection, it is an abnormal sign. Persistent pain that does not respond to painkillers, accompanied by tightness, cold skin, or numbness in the injected area, may indicate vascular occlusion. Patients should not wait for the pain to subside but should seek medical attention immediately.

An aesthetic department doctor advises a woman. Illustration: Tam Anh General Hospital

Skin discoloration

Changes in skin color are a characteristic sign of tissue necrosis. When blood flow is obstructed, the affected skin initially appears pale and feels colder than the surrounding areas. Subsequently, the skin gradually turns bluish-purple or mottled red in a net-like pattern. This indicates severe tissue ischemia; if not treated promptly, the tissue will begin to die. Areas with rich vascular networks, such as the nose, nasolabial folds, and lips, often show the most prominent discoloration.

Ulceration at the injection site

This is a late and clear sign of necrosis after filler injection. When tissue has died, deep ulcers, blisters containing yellow fluid or blood, and burning pain begin to appear on the skin surface. These lesions can spread rapidly and lead to severe infection, potentially causing permanent scarring even with aggressive treatment.

Headache, blurred vision

In some cases, systemic symptoms such as headache, dizziness, nausea, or blurred vision may occur. This usually happens when filler enters critical blood vessels around the eyes or brain. If not addressed immediately, patients risk permanent vision loss.

To prevent necrosis from filler injections, Doctor Thuy advises individuals to choose reputable facilities, well-trained doctors, sterile medical injection procedures, and fillers with clear origins. Additionally, patients should undergo a thorough examination before injection, avoiding injections in overly dangerous areas or if they have a history of complications.

After injection, close monitoring is essential during the first few hours, and patients must adhere strictly to aftercare instructions. It is important to note early signs appearing within the first 24 hours, as this is the "golden hour" for intervention and reversing tissue ischemia, according to Doctor Thuy. If any abnormal symptoms appear, seek immediate medical attention from a specialist for assessment and appropriate treatment. Delaying treatment can lead to widespread tissue necrosis, difficult-to-treat scarring, and the need for surgical intervention.

Trinh Mai