Retained intracorneal human hair fragment: An unusual case of occupational trauma.

A 32-year old male hairdresser presented with redness and irritation of the left eye for past 15 days. A fragment of hair was found embedded in deep corneal stroma with minimal scarring. No evidence was found of previous or current inflammation incited by this foreign body. The position and depth of the hair fragment was documented by anterior segment optical coherence tomography (AS-OCT) and its effect on the corneal endothelium was assessed by specular microscopy. Hairdressers should take adequate precautions to prevent ocular injury although human hair appears to be well tolerated by the cornea.

Introduction

Many types of linear foreign bodies can enter the eye following trauma[1] penetrating deeply into the cornea and anterior segment. Hairdressers may have an occupational risk for ocular injury by projectile fragments of hair.

We describe the rare case of a well-tolerated human hair corneal foreign body in a hairdresser. One report has described the corneal reaction to a fragment of the patients own hair,[2] but to the best of our knowledge, this is the first report of a well-tolerated allogenic intracorneal hair foreign body.

Case Report

A 32-year-old male hair stylist presented with redness and irritation of the left eye for the past 15 days. Direct questioning revealed a similar episode of pain and irritation 5 months back when a hair fragment was removed from the eye.

His best-corrected visual acuity was 6/6 in both eyes. Examination revealed multiple fragments of hair embedded in the bulbar conjunctiva, corneal epithelium and superficial stroma. One fragment of hair (1.8 mm) was found in deep corneal stroma 1 mm from the infero-temporal limbus. It was tapered at both ends and placed obliquely with the lateral tip entering the anterior chamber. A faint stromal scar was seen along the shaft of the hair at the level of the descemets membrane [Figure 1]. A stromal entry track could not be identified, and there was no active inflammation or infiltration.

Figure 1

Slit lamp biomicroscopy of the left eye showing an intracorneal elongated foreign body consistent with human hair. A faint stromal scar is seen along the shaft of the hair at the level of the descemet's membrane

Specular microscopy showed a linear foreign body with an oval cross section, consistent with a hair [Figure 2]. The corneal endothelium showed a significant lowering of endothelial count over the temporal cornea (2152 cells/mm2) when compared to the central cornea (3006 cells/mm2) and the other eye (3054 cells/mm2). Differential pachymetry also showed localized corneal edema. The position of the foreign body was confirmed by anterior segment optical coherence tomography. No attempt was made to remove the deeper fragment of hair.

Figure 2

Specular microscopy of the left eye showing a cylindrical corneal foreign body

Discussion

Linear, intracorneal foreign bodies may enter the cornea by trauma,[1] ocular surgery, direct contact with the source of hair, or indirect contact by rubbing the eye.[2] It has been noted that the eye can tolerate a retained cilia almost indefinitely.[1] After the initial entry, a reaction is usually elicited, followed by a quiescent period during which the foreign body can migrate in the cornea[234] and even penetrate intraocularly to the iris, vitreous, and retina.[5]

We found only one case report where a stromal reaction was elicited by a fragment of the patients own hair migrating through the corneal epithelium and stroma.[4] The exact mechanism by which hair enters and migrates in the corneal stroma is not known and may depend upon the force with which the hair strikes the eye, nature of the hair, associated pathogens and the individual's immune response.[12345]

We highlight this case because the fragment of intrastromal human hair caused no inflammation or symptoms. Ocular injury by hair fragments may be an occupational hazard to hair stylists, and adequate precautions should be taken.