Description of the condition
A hordeolum is a common disorder of the eyelid (Ehrenhaus 2012; Skorin 2002). It is an acute, red, painful, and localized inflammation with abscess formation, usually caused by obstructed orifices of the sebaceous glands of the eyelid. The infected sebaceous glands can be the meibomian gland in the tarsal plate (internal hordeolum) or the glands of Zeis or Moll associated with eyelash follicles (external hordeolum, or stye) (Barza 1983; Chern 2011; Gerstenblith 2012; Grant 2013; Mueller 2008; Peralejo 2008; Tasman 2013). An episode is usually self-limited and may resolve in about a week with spontaneous drainage of the abscess (Chern 2011; Deibel 2013; Lederman 1999; Peralejo 2008; Skorin 2002; Wald 2007). When the condition is severe, it is sometimes accompanied by fever or chills (Garrity 2007), and the inflammation may spread to other adjacent glands and tissue (Skorin 2002). Recurrences are also common (Garrity 2007; Skorin 2002). An untreated internal hordeolum may develop into a chalazion or generalized eyelid cellulitis (Bessette 2012; Chern 2011; Deibel 2013; Ehrenhaus 2012; Gerstenblith 2012; Lederman 1999).
Hordeola are among the most common eyelid lesions seen in clinical practice, but no data are available on the precise incidence and prevalence (Ehrenhaus 2012). Hordeola are more common in adults than in children, but are not limited to any age, gender, or racial group (Ehrenhaus 2012; Lindsley 2013). The usual cause of an acute hordeolum is the Staphylococcus aureus bacterium (Bessette 2012; Chern 2011; Ehrenhaus 2012; Gerstenblith 2012; Mueller 2008; Peralejo 2008; Tasman 2013; Wald 2007). Recent studies have reported that about 90% of hordeola are associated with S. aureus (Bharathi 2010) and that 24% of methicillin-resistant S, aureus ocular infections are eyelid disorders including hordeola (Hsiao 2012). Individuals with poor eyelid hygiene, inflammatory diseases of the eyelid (e.g., blepharitis, meibomitis, or rosacea), and stress, or experiencing hormonal changes are at greater risk of developing a hordeolum than the general population (Bessette 2012; Grant 2013).
Conservative treatment measures include warm compresses several times a day, which may help drainage. Topical antibiotics also may be prescribed by the ophthalmologist. If these fail, incision and drainage may be performed and systemic antibiotics are indicated (Chern 2011; Gerstenblith 2012; Lindsley 2013; Mueller 2008; Peralejo 2008; Tasman 2013).
Description of the intervention
According to the philosophy of traditional acupuncture, energy (i.e., qi and blood in traditional Chinese medicine (TCM)) circulates in 'meridians' located throughout the body. When the meridian energy circulation is blocked by certain pathogenic factors, pain or ill health will result. The way to restore energy circulation, health, and balance is to stimulate the appropriate combination of the estimated 400 traditional meridian acupuncture points in the body (WHO 1991) by acupuncture. According to TCM literature and clinical practice, acupuncture is effective for many kinds of eye diseases (Cheng 2010; Shen 2007). A recent systematic review also found some limited evidence for the effectiveness of acupuncture in the treatment of dry eye syndrome (Lee 2011). For other eye disorders, such as glaucoma and myopia, systematic reviews have drawn no conclusions regarding the benefit of acupuncture, mainly because of the sparse data (Law 2013; Wei 2011). Acupuncture, in a broader sense, includes several kinds of techniques (e.g., traditional body needling, electroacupuncture, moxibustion, etc.) (WHO 2003). According to TCM principles, redness, swelling, and pain of the eyelid are caused by pathogenic "wind heat" causing qi and blood stagnation at the eyelid (Shen 2007). Hence, the acupoints with the action of clearing heat are those usually used in treatment (i.e., stimulated by either needle insertion, acupressure, or bloodletting, etc). Bloodletting with a three-edged needle is used more often than other acupuncture techniques in clearing "heat", reducing swelling, and alleviating pain, and thus is the most common technique used in treating an acute hordeolum. Bloodletting for the treatment of an acute hordeolum involves the withdrawal of a very small quantity of blood, and the most commonly used points are Erjian (EX-HN6) at the ear apex and Taiyang (EX-HN5) at the temporal region (Shen 2007).
How the intervention might work
So far, few studies have explored the mechanism of acupuncture treatment for acute hordeola. The mechanism of acupuncture analgesia has been studied most widely. Different mechanisms of action have been proposed for the biological basis of acupuncture analgesia. For example, animal studies have provided evidence that acupuncture stimulates the release of neurochemicals (usually endogenous opioids or serotonin) (Han 1980; Han 2003). 'Gate theory' is another proposed mechanism for acupuncture analgesia (i.e., stimulation by the acupuncture needles may suppress the nervous system pathway of nociceptive pain signals (Man 1972)). Some studies have found that acupuncture may affect the autonomic nervous system that regulates involuntary body functions such as immune reactions and the processes that govern blood pressure, blood flow, and body temperature (Moffet 2006). Basic science studies also show that acupuncture suppresses inflammation (Li 2008), the main symptom of an acute hordeolum.
Why it is important to do this review
The most current Cochrane review of interventions for acute internal hordeola (Lindsley 2013) found that none of the most commonly used conventional treatments, including heated compresses and antibiotics or steroids, could be evaluated systematically due to the lack of randomized controlled trials (RCTs) investigating these treatments. In addition, no RCTs evaluating surgical interventions, such as incision and curettage, were identified. However, during the literature search for the Lindsley 2013 review, a number of RCTs on acupuncture for acute hordeola were identified, reflecting the popularity of this treatment and implying the need for a systematic review on acupuncture for this condition. Acupuncture has been demonstrated to be a safe treatment with very low risk of serious side effects (Cherkin 2003; Xu 2013). Four large, prospective surveys of acupuncture practitioners (MacPherson 2001; Melchart 2004; White 2001; Witt 2009) confirmed that serious adverse events after acupuncture are uncommon. Acupuncture for the treatment of an acute hordeolum is relatively convenient, usually comprising three or fewer sessions, with each session lasting for a few minutes only, which indicates its applicability in the clinic.
Given the existing evidence, a systematic review of the effectiveness and safety of acupuncture for the treatment of acute hordeola is highly desirable.