Patient characteristics are presented in Table 1. Of the ten patients (11 eyes) with BK, two were men and eight were women. The mean age was 50.3±21.0 years (range, 17 to 81 years), and the mean duration of follow-up was 11.4±6.1 months (range, 6 to 23 months). The causes of BK were prior retinal surgery using silicone oil in four eyes (36.4%), glaucoma in three eyes (27.3%), hypercalcemia in two eyes (18.2%), trauma in one eye (9.1%), and idiopathic in one eye (9.1%). Preoperatively, all patients had visual disturbances, foreign body sensation, and tearing, and one patient had photophobia.

Postoperatively, the best corrected visual acuity remained unchanged in eight eyes (72.7%) and improved in three eyes (27.3%). There was no significant difference between the preoperative and postoperative best corrected visual acuities (p=0.11). Symptoms were noticeably improved in all patients. The mean time for complete healing of the cornea was 10.6±5.3 days after surgery: 8 to 14 days in five eyes (45.5%), seven days or less in four eyes (36.4%), and 15 days or more in two eyes (18.2%). The cosmetic results were good in eight eyes (72.7%) and fair in three eyes (27.3%).

Calcium plaques were removed completely in all cases. Although we performed sutureless AM transplantations using fibrin glue, there were no early detachments of the AM. There were no recurrences or complications associated with the surgery during the follow-up period. At the last visit, a good corneal state was established in all patients (Fig. 1). However, in one patient with glaucoma (patient 8), evisceration was required because of uncontrolled intraocular pressure at postoperative month 17.

The goals of surgical treatment for BK are to provide a regular surface and a clear cornea, as well as to improve ocular comfort by removal of calcific deposits and correction of surface instability. Various methods have been used in the treatment of BK, including EDTA chelation, diamond burr, superficial keratectomy, Nd:YAG laser, and PTK [3-5,7,8,20-22].

Calcium removal by EDTA chelation is by far the most widely used method [3-5,7,8,20-22]. Najjar et al. [3] reported partial or complete symptomatic relief and improvement by two or more lines of visual acuity after EDTA chelation in 90% and 33% of patients, respectively. Because treatment using EDTA mainly focuses on the removal of calcium plaques in the epithelial layer, the removal of deeply impacted calcium deposits in the stromal layer is difficult to achieve using this method [4,7,18,19,21]. When the calcium plaques are thick or deeply positioned, the procedure is performed mainly to improve ocular comfort, not to improve vision; in this case, the recurrence rate is higher than that for other treatment procedures [3-5,19]. Moreover, calcium plaques resistant to EDTA may remain after treatment, causing an irregular corneal surface [7]. Therefore, EDTA chelation has the limitation of requiring additional procedures, such as PTK [5,19].

PTK has been used effectively for various superficial corneal disorders, such as recurrent corneal erosion, corneal opacity, and bullous keratopathy [9,10]. The indiscriminate ablative action of PTK that removes the corneal surface involving the superficial stroma is useful for treatment of BK with deeply situated calcium plaques and for restoring a regular surface [7,8]. O'Brart et al. [7] reported improvement of symptoms in 95% of patients and of visual acuity in 88% of patients with smooth-band keratopathy after PTK. Stewart and Morrell [8] also reported that symptoms were relieved in 83% of the nonvisual group and visual acuity improved or remained unchanged in 55% of the visual group after excimer laser PTK. However, several complications with PTK have been reported, including severe pain from the healing of the epithelium and variable refractive changes [7,8].

AMT has recently been performed to complement conventional treatments for BK [18,19]. Many previous studies have reported on the beneficial properties of AM that facilitate corneal epithelialization and suppress ocular surface inflammation and opacity, both in vivo and in vitro [11,17]. AM can protect stromal defects by replacing the removed basement membrane and stroma after superficial keratectomy or excimer laser PTK, resulting in a decrease in surgically-induced pain, corneal haze, neovascularization, and apoptosis [16,19]. Anderson et al. [18] performed AMT after surgical removal of calcific deposits with or without the use of EDTA in 16 eyes of 15 patients with BK. Symptoms resolved in all cases, and epithelialization was achieved in 93.7% of cases with a mean healing time of 15.2 days. Visual acuity improved in 44% and remained unchanged in 56%. Kwon et al. [19] treated two patients with AMT following EDTA chelation and superficial lamellar keratectomy. They reported that complete re-epithelialization was achieved in 9-10 days without any symptoms, complications, or recurrence.

Our strategy for the treatment of BK consists of the combination of three techniques: EDTA chelation and excimer laser PTK followed by AMT. In the present study, complete healing of corneal defects was achieved in all patients with a mean time of 10.6±5.3 days after surgery. This healing time is satisfactory considering that the corneal defects after PTK were deep to the anterior stroma in our patients. Symptoms such as pain, foreign body sensation, tearing, and photophobia noticeably improved in all cases without complications or recurrences during the follow-up period. Best corrected visual acuity improved in the 27.3% of patients that had systemic diseases or an idiopathic cause, whereas it remained unchanged in the 72.7% that had associated ocular diseases. Consistent with previous reports, this finding suggests that postoperative visual acuity may not improve with BK caused by concurrent ocular pathology, despite treatment [8,18,21]. Spherical equivalents could not be measured preoperatively because of thick calcium depositions at the anterior stroma, and so no data about refractive changes after PTK were available. The cosmetic results were generally satisfactory.

We performed a sutureless AM surgery using fibrin glue. This procedure has several advantages, including low-grade irritation and scar formation, a low frequency of graft loss by atrophic changes, and a shorter operation time compared to that of the suture techniques [23,24]. In addition, the technique does not require suture removal after surgery. Our combined approach for the treatment of BK has drawbacks of a longer operation time and greater expense. However, the combined procedure can prevent additional costs and time spent on reoperation due to recurrent lesions. That we saw no recurrence in our study may be explained by two factors: first, compared with previous reports [3], the mean follow-up period in this study was shorter. Second, in contrast to single procedures [3,7], the combined procedure may inhibit lesion recurrence [19]. In the future, a long term follow-up study with a large sample size will be needed.

In conclusion, because of the limitations of conventional techniques, we suggest that a combined treatment of EDTA chelation and PTK followed by AMT using fibrin glue for deeply situated calcium deposits in band keratopathy can induce symptom relief, reduce healing time, and prevent recurrence. Therefore, the combined procedure can be a safe and reliable approach to manage band keratopathy. Further studies with a prospective randomized design and a larger sample size with a control group are needed.