Acupuncture is a traditional treatment method developed in East Asia over a significant period of time and is now recognized as an important component of complementary and alternative medicine worldwide [1-3].

In the field of ophthalmology, papers have been published on the effectiveness of acupuncture for some ophthalmologic diseases, and meta-analysis of diseases, such as dry eye syndrome, glaucoma, slowing myopia progression, amblyopia, and acute hordeolum, have been published or are in progress [2-8]. Recently, several studies, including meta-analysis, regarding dry eye syndrome have been reported and are in the spotlight [4,5,9]. However, adverse events, such as penetrating injuries caused by acupuncture around the eyes, have been reported constantly [10-22]. These disastrous events are related to the site of acupuncture, which depends on the target disease.

Generally, periocular acupuncture may affect the ocular surface condition as either an effect or a possible side effect. Therefore, the target disease, location of acupuncture, expected benefits, and frequency and severity of serious side effects need to be discussed together. In this article, we reviewed the literature of previously reported ocular penetration caused by acupuncture to provide information on the safety of acupuncture treatment around the eye in an organized manner.

Although eyeball perforations are known to be mainly caused by trauma, they may also occur as a complication of retrobulbar anesthesia for intraocular surgery, such as cataract surgery and trabeculectomy [43,44]. Perforations are usually managed by PPV. In cases where retinal damage is not severe, treatment with endolaser alone has been reported [16,19]. However, in cases of perforation injuries caused by nonaseptic manipulation, such as periocular acupuncture, PPV was mainly performed [12,14-16,18,21,22]. In our review of cases, PPV was performed in six of 10 eyes with eyeball perforation. Vitreous hemorrhage was the most common cause of vitrectomy, and retinal detachment was observed in one case.

In the case of ocular acupuncture injury, it is thought that by removing vitreous hemorrhage and inflammatory products through PPV, ophthalmic fibrous proliferation is reduced to make the retina more stable, and bacterial endotoxins are removed as much as possible, thereby reducing the possibility of bacterial endophthalmitis [45-47]. In the case of patient 11, Lee et al. [22] considered the possibility that bacterial endophthalmitis occurred in both eyes after acupuncture injury. The patient underwent vitrectomy of only the right eye. Although PPV was not performed in the left eye, pain and VA improved after laser photocoagulation and intravenous administration of broad-spectrum antibiotics. However, the visual prognosis of the left eye was worse than that of the right eye. Since acupuncture-induced ocular perforation may not be caused by aseptic manipulation [18], early treatment should be actively considered through vitrectomy to remove vitreous hemorrhage, inflammatory products, and bacterial toxins.

Acupuncture around the periorbital region poses a risk of perforation and infection, especially if performed by an unqualified individual [15,22]. At least three of the 15 cases in our review were procedures performed in unlicensed acupuncture centers. Of note, permanent vision loss can arise from acupuncture. Therefore, acupuncturists should get familiar with the eye anatomy of acupoints and avoid blood vessels or nerves during needle manipulation and avoid manipulation methods, such as thrusting or vigorous lifting, when acupuncturing intraorbital acupoints [48]. Similar to acupuncture, intravitreal injection is also performed to treat eye diseases, such as neovascular age-related macular degeneration, diabetic retinopathy, and retinal vein occlusion [49,50]. There is also a risk of infection in the case of intravitreal injection for therapeutic purposes. Therefore, it should be performed under aseptic conditions after administering betadine to the eye. The injection needle penetrates only through the plane of the ciliary body. This is because the flat part of the ciliary body is a narrow area of approximately 4 mm, and when the puncture point is out of that range, ciliary body and retinal hemorrhage, as well as retinal tear and detachment, may occur [18,51]. Acupuncture performed without recognizing the importance of aseptic manipulation may pose a risk of endophthalmitis, vitreous hemorrhage, and retinal tear. In the case of patients 7 and 11 [18,22], endophthalmitis was presumed to have occurred based on pain, intraocular inflammation, and vitreous opacity. The risk of endophthalmitis, vitreous hemorrhage, and retinal laceration is higher when nonsterile techniques are adopted by unlicensed acupuncturists. Therefore, aseptic acupuncture should be performed by licensed acupuncturists. Adequate training of modern acupuncturists, particularly emphasizing the study of sterile needle techniques and knowledge of human eye anatomy, is important and is required to prevent periocular adverse events. Since modern acupuncture, which is currently being practiced in several countries, emphasizes knowledge of eye anatomy and aseptic acupuncture, it is supposedly less likely to cause periocular adverse events.

Periocular acupuncture is being performed worldwide for many ophthalmologic and nonophthalmologic conditions, such as headache, trigeminal neuralgia, neck stiffness, and acute lumbar sprain [17,26]. The incidence of complications, including perforation, is likely to increase as the acupuncture site is in close contact with the orbital margin. Additionally, vision loss may occur because of ocular perforation. Therefore, care should be taken during acupuncture, the patients should be closely monitored after the procedure, and any possible future complications should be noted. All these acupuncture points are anatomically predisposed to optic nerve injury and globe perforation owning to the proximity of the eyeball structures. Therefore, the acupuncturist should recognize and distinguish between the pain caused by penetrating eyeball or optic nerve injury and the pain occurring as part of the therapeutic effect of the acupuncture. Many patients and practitioners mistakenly think that a stronger pain sensation will give rise to better outcomes [48], when in fact, they cause severe adverse events, such as eyeball perforation. It may equally be important to have a good understanding of the ocular anatomy to avoid potential complications.

In our review, no specific periocular area was identified as more prone to eyeball injury. A direct link between the acupuncture site and penetrating injury was not observed. As shown in Table 2 [10-22], only three cases (cases 8, 11, and 12) reported specific acupuncture sites out of 12 eyes with penetrating injury, and the acupuncture sites were ST1, Ex-HN4, and GB1, respectively. Therefore, ocular damage could be induced at various periocular sites, but the relationship between specific sites and injury could not be analyzed because of the small number of cases.

Acupuncture therapy around the eye is a risky procedure, with no robust evidence of its benefits. Hence, it is important to have a good understanding of eye anatomy to avoid potentially blinding complications. Additionally, it is necessary to strictly monitor the patient’s condition after the procedure, and any complications and associated symptoms that may occur in the future should be explained to the patient in detail.