Corneal keloid: four case reports of clinicopathological features and surgical outcome

Lee et al. BMC Ophthalmology (2016) 16:198 DOI 10.1186/s12886-016-0372-4 CASE REPORT Open Access Corneal keloid: four case reports of clinicopathological features and surgical outcome Hyo Kyung Lee1, Hyuk Jin Choi1,2, Mee Kum Kim1,2, Won Ryang Wee1,2 and Joo Youn Oh1,2* Abstract Background: Surgical outcome of corneal keloid is largely variable depending on reports, although surgical management is inevitable in visually significant cases. We here report clinical features, histopathological findings, and surgical outcome of four cases of corneal keloid. Case presentation: Four Korean male patients without a history of corneal trauma or disease were clinically and histologically evaluated for a slowly-growing, white opacity in the cornea. On slit lamp examination, corneal lesions appeared as a solitary, pearly white, well-circumscribed nodule with a smooth and glistening surface. Because the lesions involved the visual axis deteriorating the visual acuity, the nodules were surgically removed by superficial keratectomy in all patients. Amniotic membrane transplantation was combined in three patients, and an intraoperative mitomycin C application in two patients. Hematoxylin-eosin staining of the excised nodules revealed epithelial hyperplasia, Bowman’s layer disruption, thick and irregularly-arranged collagen fibers in the stroma, and accumulation of prominent fibroblasts, which are consistent with the diagnosis of corneal keloid. The corneal keloids recurred in all patients within 10 months of surgical excision and outgrew the boundary of the excised area. Conclusion: A diagnosis of corneal keloid should be suspected in patients presenting with an enlarging, white, glistening corneal nodule, even in the absence of a history of corneal trauma or disease. The recurrence is common after surgical excision, and the lesion can be exacerbated by surgery. Keywords: Case report, Corneal keloid, Superficial keratectomy, Amniotic membrane transplantation, Mitomycin C, Background Corneal keloid is a benign proliferation of fibrous or fibrovascular tissue in the corneal stroma, and presents as a single, enlarging, white, elevated, well-circumscribed corneal lesion with glistening surface [1]. Most of corneal keloids develop following a trauma or disease in the cornea, suggesting an aberrant corneal reparative process as one of the factors underlying the pathogenesis of the keloid [1]. However, several cases of primary corneal keloid have been reported in patients without a history of corneal surgery or trauma [2–4]. Surgical management is inevitable in visually significant cases of corneal * Correspondence: 1 Department of Ophthalmology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744, Korea 2 Laboratory of Ocular Regenerative Medicine and Immunology, Biomedical Research Institute, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744, Korea keloid, but its outcome is largely variable depending on reports. We herein report the clinical features, histopathology, and surgical outcome of primary corneal keloids in four Korean patients who did not have a history of corneal trauma or disease. Case presentation The study was approved by the Institutional Review Board of Seoul National University Hospital. The patient characteristics were summarized in Table 1. Case 1 A 21-year-old man presented with a slowly-growing, white opacity in the right cornea. The patient had been diagnosed with osteogenesis imperfecta, and received strabismus surgery in both eyes at the age of five. Otherwise, he © The Author(s). 2016 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Lee et al. BMC Ophthalmology (2016) 16:198 Page 2 of 5 Table 1 Summary of patient characteristics Case 1 Case 2 Case 3 Case 4 Sex Male Male Male Male Laterality Right Left Both Right Age at presentation 21 years 4 years 16 years 62 years Systemic comorbidity Osteogenesis imperfecta Neuro-fibromatosis type 1 - - Ocular surgery Strabismus surgery (both) Epiblepharon repair (both) Epiblepharon repair & frontalis PRK* (both) Vitrectomy sling operation (both) (right) Age at the time of ocular surgery 5 years 4 years 4 years 44 years (PRK*) 53 years (vitrectomy) * PRK: Photo-refractive keratectomy denied having a history of ocular trauma, infection or inflammatory disease. On initial examination, the best corrected visual acuities (BCVA) were 20/125 in the right eye and 20/20 in the left eye. Slit-lamp biomicroscopy showed a pearly white, elevated opacity in the right cornea with distinct margins and smooth surface (Fig. 1a). New vessels were partially present in the lesion adjacent to the limbus. The left cornea was clear. The lesion was removed by superficial keratectomy (SK), and the residual stromal bed was temporarily covered with an amniotic membrane (AM). Histopathologic examination of the excised lesion revealed hyperplastic epithelium, the absence of Bowman’s layer, and abundant, erratically-interlaced collagen fibers with prominent fibroblasts in the stroma (Fig. 2a). The clinical and histologic findings were compatible with a diagnosis of corneal keloid [1]. One month after surgery, the patient’s vision improved to 20/50, and the cornea appeared clear except for a fine reticular subepithelial haze (Fig. 1b). However, 4 months later, corneal opacification recurred and worsened along with more severe new vessel ingrowth at the same location as before the surgery (Fig. 1c). Fig. 1 Slit-lamp microscopic photographs of corneal keloids in four patients. a-c Case 1, (d-f) case 2, (g-i) case 3, (j-l) case 4. Shown are corneal photographs at presentation (a, d, g, j), right after superficial keratectomy (b, e, h, k), and after recurrence (c, f, i, l) Lee et al. BMC Ophthalmology (2016) 16:198 Page 3 of 5 Fig. 2 Hematoxylin-eosin staining of the excised keloid sections. a Case 1. The epithelium is hyperplastic and undulating, and Bowman’s layer is totally disrupted. The stromal collagen bundles are increased and irregularly-arranged in a whorl-like pattern. Original magnification × 100. b Case 2. A marked epithelial hyperplasia and focal disruption of Bowman’s layer are noted. Original magnification × 200. c Case 4. Thickened epithelial layer, increased stromal collagen, and numerous accumulation of prominent fibroblasts are observed. Original magnification × 100 Case 2 A 4-year-old boy presented with an enl (...truncated)