The patient: A man in his 20s in Edinburgh, U.K.

The symptoms: The man visited an eye clinic after noticing floaters — small, dark shapes drifting across his field of vision — along with brief flashes of light in his right eye for six days. He was otherwise healthy and had no history of eye disease, physical trauma to the eye, or drug use. He had mild nearsightedness, for which he wore glasses.

What happened next: Doctors performed a thorough eye exam while the patient wore glasses, finding that his corrected vision measured 6/6 in both eyes, the metric equivalent of 20/20. His eye pressure was also normal.

However, a closer examination of the patient's retinas, the light-sensitive layer lining the back of the eye, revealed significant damage in both eyes, according to a report of the case.

In the right eye, doctors found multiple retinal tears and bruising, as well as a retinal dialysis, a rare type of tear in which the retina begins to separate from its outer edge where it connects to other tissues of the eye. Without treatment, retinal dialysis can progress to full retinal detachment and cause permanent vision loss. The left eye also had bruising and six small, horseshoe-shaped retinal tears: three at the top and three on the side of the retinal tissue.

Since these injuries are typically caused by sudden trauma to the eye ‪—‬ from a punch or sports injury, for instance ‪—‬ doctors revisited the patient's history and asked whether anything unusual had happened involving his eyes.

The patient, described in the case report as a "hesitant historian," later disclosed that he had been using a percussive massage gun directly on and around his eyes for the past three months. He had bought the device himself and used it weekly for several minutes at a time without medical guidance, in an effort to relieve a "feeling of tiredness" in his eyes.

The diagnosis: Doctors concluded that the patient's retinal injuries were most likely caused by this improper use of the massage gun, according to the case report. These devices deliver rapid, high-frequency pulses of pressure that are intended to relieve muscle tension. However, they can cause severe damage to delicate tissues like those found in the eyes.

The eye is filled with a gel-like fluid that helps it maintain its shape. The case report authors suggested that, each time the device put the eye under pressure, it may have briefly distorted the eye's shape. Over time, this repeated stress may have placed strain on the retina, eventually leading to the small tears.

This pattern of injury was also different from what's seen in typical retinal dialysis cases, they noted. The condition most often occurs in the lower, outer part of the retina, along its bottom edge. In this patient, however, the injury was found in the retina's upper region, which his doctors said may reflect repeated forward pressure from the device rather than a conventional lateral impact, such as blow to the head.

The treatment: Around 8% to 15% of retinal dialysis cases can progress to retinal detachment, which can lead to vision loss. In this case, however, the patient's vision was preserved.

The retinal tears in both eyes were treated with laser therapy; targeted laser burns create scar tissue that helps seal the retina in place and thus prevent fluid from seeping underneath. The right eye's retinal dialysis was treated with "barrier laser therapy," which similarly creates a protective scar around the affected area to reduce the risk of progression.

At a follow-up six months later, the patient's condition remained stable, with no further damage or cataract formation (clouding of the eye's lens). Doctors reported that the positive outcome was "likely due to the patient's prompt presentation soon after noticing symptoms and the immediate initiation of treatment."

What makes the case unique: Eye injuries linked to massage guns are rarely reported. The small number of cases that appear in the medical literature suggest they can sometimes cause serious or permanent damage.

In one such case, a 69-year-old man developed severe eye complications, including lens dislocation and glaucoma (a sudden rise in eye pressure) after using a massage gun near his eye for several weeks. In another case, a 38-year-old woman developed a dense traumatic cataract — a type of cataract that forms due to physical injury — and severe vision loss after using a similar device over her temple and eye region.

The Edinburgh man's case is the first to report retinal dialysis and multiple retinal tears linked to massage gun use. Such injuries are usually associated with high-energy trauma, such as road traffic accidents, sports injuries or a direct blow to the eye, or they occur in people with underlying risk factors, including severe nearsightedness or age-related eye changes, the case report authors noted.

In this case, the young man had none of these known risk factors. The extent of the damage in the absence of these risk factors raises concerns about the effects of improper use of massage guns near the eyes, his doctors concluded.

Massage guns are widely sold for at-home use, but there are currently no standardized safety guidelines for using them on or near sensitive areas, such as the eyes. The authors of the case report said the man's case highlights the need for clearer manufacturer warnings and greater awareness of the potential risks of improper massage gun use.

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