Use of medical sodium hyaluronate gel in surgical removal of a glass intraocular foreign body.

A 38-year-old healthy man presented to our department of ophthalmology after sustaining an ocular injury in a glass explosion more than 10 days prior. A glass intraocular foreign body (IOFB) was found in the left eye. During surgical removal of the IOFB, medical sodium hyaluronate gel was used to detach the IOFB from the retina; this avoided damage to the retina and made it easier for the surgeons to grasp the glass fragment. Multiple surgical instruments have been developed to help remove IOFBs; however, many optic hospitals have limited surgical instruments, thus increasing the difficulty of the operation. The application of sodium hyaluronate gel, a widely used agent, may be a new technique in IOFB surgery.

Introduction

Ocular trauma accounts for 7.00% to 9.22% of all bodily injuries.[1] Traumatic eye injuries involving intraocular foreign bodies (IOFBs) may result in severe visual loss. After identifying the size and location using computed tomography and B-scan ultrasonography, a diamond-coated IOFB forceps should be used to remove 1- to 3-mm glass shards, whereas >3-mm glass fragments require a diamond-coated forceps.[2] However, glass fragments are difficult to grasp because of their smooth surface. In the present case, we used medical sodium hyaluronate gel, a widely used agent in ophthalmic surgery, for easy removal of an IOFB.

Case report

A 38-year-old healthy man presented to the Department of Ophthalmology of The Third People’s Hospital of Changzhou in July 2019 after having sustained an eye injury in a glass explosion more than 10 days previously. After administration of emergency treatment at a local hospital, most of the glass fragments were removed; however, the patient complained of visual loss and photophobia. Upon examination, his visual acuity was 0.3 in the right eye and counting fingers in the left eye. Several small pieces of glass remained in the cornea, and the nasal side of the cornea was thinner than the lateral side, which may have been due to entrance of the IOFB (Figure 1). The chamber was stable without cells or flare. The pupil was round, measured 3 mm in diameter, and was sensitive to light, and the lens appeared transparent but was not very clear. Computed tomography (Figure 2) and ultrasonography (Figure 3) were performed to identify the size and position of the IOFB.

Figure 1.

Anterior segment optical coherence tomography of the cornea.

Figure 2.

Computed tomography findings.

Figure 3.

Ophthalmic ultrasound findings.

To avoid secondary retinal damage, we surgically removed the IOFB. Intraoperatively, we found that the glass fragment was too large, smooth, and tightly attached to the retina to be grasped with a claw forceps (Figure 4). Therefore, we injected medical sodium hyaluronate gel for intraocular use (Healon; Johnson & Johnson Vision, Jacksonville, FL, USA) into the posterior segment to protect the retina and slow the decline of the glass. After picking up one side of the glass using a retinal brush, the Healon flowed under the glass, and the glass stayed upright because of the viscosity of the Healon. The glass was finally grasped with the claw forceps (Figures 5 and 6).

Figure 4.

Large glass piece tightly attached to the retina.

Figure 5.

Foreign body removal. From left to right: hyaluronate gel was injected onto the retina, the piece of glass was pried up with the retina brush and remained upright, and the glass was removed with a claw forceps.

Figure 6.

Removal of the piece of glass with a claw forceps.

Postoperatively, the patient recovered well. One week after the surgery, optical coherence tomography of the site of IOFB removal showed no abnormality of the retina, and the visual acuity of the left eye was 0.3 (Figure 7).

Figure 7.

Postoperative optical coherence tomography image of the site of foreign body removal.

Discussion

Because of inadequate occupational health and safety training, the incidence of IOFBs is high in China and results in vision loss in many patients.[3] Unlike metallic and vegetative IOFBs, glass pieces have stable chemical properties and cannot be extracted in some cases. One review revealed no complications when glass IOFBs were left intact, while 13 of 43 eyes that underwent surgical removal sustained iatrogenic retinal damage.[4] However, mechanical complications such as macular injury and retinal laceration may arise from the retained glass.[5] In the present case, the piece of glass was >3 mm in diameter, and we decided to surgically remove the IOFB to avoid secondary retinal damage.

Previous reports have indicated that metallic IOFBs of >3 mm and nonmetallic IOFBs require specialized IOFB grasping forceps for removal.[6] However, many hospitals have limited surgical instruments, and removal of IOFBs with normal grasping forceps may be challenging. Application of sodium hyaluronate gel, a widely used agent, may be a new and useful technique in IOFB surgery.

Because a piece of glass is flat, it is difficult to grasp its wide edge when it is attached to the retina. However, its narrow edge may be easier to grasp when in the upright position. The density of glass is approximately 2.5 g/cm3, and that of heavy water is 1.77 g/cm3; this indicates that a glass IOFB may not float upward even after injecting heavy water. Sodium hyaluronate (density of approximately 1.1 g/cm3) has high viscosity and flows slowly when applied with external force. In this case, after we had picked up one side of the glass using a retinal brush, Healon flowed under the glass. Because of its high viscosity, the Healon flowed slowly and held the glass upright for a few seconds, making it easier to grasp.

Sodium hyaluronate is used as a viscoelastic gel to facilitate healing and regeneration of surgical wounds. It prevents damage to the endothelial layer of the cornea, functions as a lubricant, eliminates physical damage to other tissues, and maintains an adequate operative space and depth of the anterior chamber. It is particularly important in glaucoma surgery, anterior segment surgery, and corneal transplantation.[7] In addition, sodium hyaluronate reduces the intraocular pressure in implant surgery. Furthermore, it can be used to treat dry eye, to reposition and unroll the retina following detachment, and to treat anterior synechiae lysis, tissue separation, and mechanical adhesions.[8,9]

In the present case, sodium hyaluronate gel was used as a viscoelastic agent to keep the glass fragment upright for a few seconds, facilitating easier grasping of the IOFB.

Conclusion

Sodium hyaluronate is used worldwide. If appropriate forceps for IOFB surgery are not available or the IOFB position needs adjusted and held, sodium hyaluronate gel may be effectively used because of its high viscoelasticity.