Hypertrophic scar of the conjunctiva presenting as an eyelid mass: an unusual complication after surgical treatment of a chalazion

Purpose To present a rare case of a conjunctival hypertrophic scar presenting as eyelid mass after surgical treatment of a chalazion. Case presentation A 74-year-old man visited our clinic with severe ocular discomfort and excessive lacrimation since several months in his left eye accompanied by itching of the upper eyelid. Examination of the anterior segment revealed a 6 mm (horizontal) × 8 mm (vertical) round, immobile, hard, mushroom-shaped protruding mass on the tarsal conjunctiva of his left eye. There was no associated pigmentation, ulceration, or tenderness. Excisional biopsy of the benign conjunctival tumor was performed using radiofrequency electrosurgical systems. The region of the excised conjunctiva was well-healed on postoperative day 14, and there was no recurrence until 1 year post-surgery. Histopathological examination demonstrated thick interlacing collagenous fibrous bundles oriented in random directions and fibroblastic proliferation. Immunohistochemical staining revealed that spindle-shaped fibroblasts were positive for CD34 and negative for smooth muscle actin. The excessive collagenous tissue was stained blue by Masson trichrome stain. These findings were consistent with a hypertrophic scar of the conjunctiva. Conclusion This short report demonstrates that a hypertrophic scar of the conjunctiva can develop after surgery of a chalazion and cause severe ocular discomfort and excessive lacrimation. These lesions can be easily removed using simple excision.


Background
Hypertrophic scars of conjunctival tissues following ocular surgery do not develop commonly (Lyu et al. 2013;Urban and Kaufman 1994;D'Hermies et al. 2003). To date, there have been few reports of hypertrophic scars after chalazion surgery (D'Hermies et al. 2003).

Case presentation
A 74-year-old man visited our clinic with severe ocular discomfort and excessive lacrimation since several months in his left eye accompanied by itching of the upper eyelid. Four months prior, he underwent surgery for a chalazion secondary to posterior blepharitis.
Examination of the anterior segment revealed a 6 mm (horizontal) × 8 mm (vertical) round, immobile, hard, mushroom-shaped protruding mass on the tarsal conjunctiva of his left eye. There was no associated pigmentation, ulceration, or tenderness (Fig. 1a). Excisional biopsy of the benign conjunctival tumor was performed using radiofrequency electrosurgical systems (Ellman International Inc., Oceanside, NY) under local Open Access *Correspondence: mdshlim@gmail.com 3 Department of Ophthalmology, Daegu Veterans Health Service Medical Center, #60 Wolgok-ro, Dalseo-gu, Daegu 704-802, Republic of Korea Full list of author information is available at the end of the article anesthesia ( Fig. 1b). The region of the excised conjunctiva was well-healed on postoperative day 14 (Fig. 1c), and there was no recurrence until 1 year post-surgery.
On microscopic examination, the lesion was composed of spindle-shaped fibroblasts and collagenous stroma (hematoxylin & eosin stain, 40×, Fig. 2a). A section of the specimen showed thick, interlacing, collagenous fibrous bundles oriented in random directions and fibroblastic proliferation (Fig. 2b, c). Immunohistochemical staining revealed that spindle-shaped fibroblasts were positive for CD34 and negative for smooth muscle actin. The excessive collagenous tissue was stained blue by Masson trichrome stain (Fig. 2d-f ). These findings were consistent with a hypertrophic scar of conjunctiva. And there was no evidence of the malignancy.

Discussion
Conjunctival hypertrophic scars following ophthalmic surgery are rare (Lyu et al. 2013;Urban and Kaufman 1994;D'Hermies et al. 2003). In previous studies, cryotherapy for retinopathy of prematurity (Lyu et al.  gradually developed on the conjunctival face of the eyelid disturbing the use of contact lens, which was diagnosed as a "hypertrophic eyelid conjunctival scar". A hard and fibrous lesion was resected under local anesthesia in their report. In our case, we performed a similar simple resection using radio frequency electrosurgery.
Differential diagnosis includes keloid and angiofibroma. Keloid is less cellular and has thicker collagen fibers. Angiofibroma is characterized by small vessel dilatation and concentric perifollicular fibrosis. The histologic features of the present case are compatible with hypertrophic scar.
The eyelids are dynamic and complex structures. The primary function of eyelid is to protect the ocular surface via cleansing and lubrication of eyes. They serve as both a physical and immunological barrier, which constitutes a crucial defense mechanism (Lin et al. 2011). In these contexts, a hypertrophic scar on the tarsal side of the conjunctival tissue presenting as an eyelid mass could cause tear film instability and secondary ocular surface disease.

Conclusion
This case report demonstrated that a hypertrophic scar of the conjunctiva can develop after surgical treatment for a chalazion and cause severe ocular discomfort and excessive lacrimation. These lesions can be easily removed using simple excision.