Intraocular glass foreign body-Retained amiss!

Open globe injuries with intraocular foreign bodies are important cause of visual morbidity. Timely detection of foreign body is must to improve the visual outcome and to prevent eye from developing complications. It is important to understand the need of meticulous history taking and thorough examination besides other investigations to detect foreign body. Glass foreign bodies are little difficult to visualize because of its transparent nature. The best time to detect foreign body is at the time of primary repair. Until one suspects the presence of foreign body, it is missed most of the time. We chose to report this case as it is unusual to miss big IOFB in anterior chamber impacted in lens matter at the time of primary corneal repair. It is important to remember that an ounce of vigilant vision is worth a pound of care.

Introduction

Open globe injuries with retained intraocular foreign body (IOFB) are an important cause of visual morbidity. Timely detection of IOFB is must to improve the visual outcome and to prevent the eye from developing complications. It is important to elicit history meticulously in the setting of trauma. Thorough ocular examination and investigations like imaging and/or electrophysiology help to detect IOFB. Glass foreign bodies are difficult to visualize because of their transparent nature. The best time to detect a foreign body is at the time of primary repair. One must have a high degree of suspicion for a retained IOFB given the setting of trauma; else it is likely to be missed. We report this unusual case, wherein a large glass foreign body impacted within the lens and obscured by the intumescent cortical matter was missed at the time of primary corneal repair. It is important to remember that an “ounce” of vigilant vision is worth a “pound” of care. Foreign bodies may present in obscure clinical situations that may limit its detection. The following case report illustrates an uncommon case of “intralenticular glass foreign body” missed during primary repair.

Case Report

A 58-year-old male presented with complaints of diminution of vision in right eye following road traffic accident 6 days back. On enquiring, he revealed that following the impact he fell on ground and was hit by a projectile stone. But he denied having noticed any apparent entry of stone inside the eye. The patient underwent primary corneal tear repair, elsewhere on the same day and presented to us 3 days later. At the time of presentation, vision in right was perception of light and 6/6 in left eye. Anterior segment (AS) examination of the right eye showed multiple corneal sutures from limbus to limbus (3-9 O clock). Anterior chamber was formed and fluffy cortical matter with ruptured anterior capsule was seen [Figure 1]. There was no evidence of ocular infection. Fundus details could not be seen as there was no view due to traumatic cataract. Left eye was essentially normal. Ultrasound scan of the right eye revealed retina attached throughout with no evidence of posterior globe dehiscence. However, strong reverberation echoes were seen emanating from the lens [Figure 2, green arrow]. The patient was examined again on slit lamp with a strong suspicion of retained foreign body. A shiny silver edge of glass was seen just behind the suture line lying “edge-on” [Figure 1 green arrow]. The lack of contrast between the horizontally oriented glass foreign body lying edge-on within the white, fluffy cortical matter, just behind the suture line made its prior detection difficult. Intraocular pressure was normal in both the eyes. The glass piece was removed in toto through a corneoscleral tunnel along with the cortical matter in the anterior chamber. Glass foreign body piece was a thin chip, pyramidal in shape, and measured approximately 8 × 6 m m mmin dimension [Figure 3]. Patient was doing well on first post-operative day. Six weeks later, he presented with central leucomatous corneal opacity and could appreciate only hand movements. Retina was well well-attached. The patient was advised to review after two 2 monhsths mont and was counselledcounseled for the need of penetrating keratoplasty in the future.

Figure 1

Slit Lamp lamp photograph showing shining edge of glass IOFB within the substance of the traumatic cataract

Figure 2

B-scan showing reverberation echoes from intraocular foreign body persisting at low gain

Figure 3

Glass foreign body, a thin chip, pyramidal in shape and measured approximately 8 mm × 6 mm mmin dimension. (Scale for dimension)

Discussion

Ocular trauma is an important, preventable, public health problem worldwide. Open globe ocular injuries constitute a major cause of visual morbidity with significant socioeconomic impact. Open globe injury with or without IOFB often has a poor visual outcome owing to possible endophthalmitis and/or vitreo retinopathy with the varied and unsterile wounds associated with it. IOFB constitute 18%-41% of open globe injuries.[1] Intralenticular foreign bodies constitute approximately 5%-10% of all IOFB.[123] Intraocular foreign bodies are usually detected at the first visit. The majority of injuries are caused by flying pieces of metal while hammering or chiseling at work. Road traffic accidents also contribute considerably.[45] The perforating injuries range from self-sealing wounds to severe corneoscleral or scleral lacerations, with intraocular bleeding and vitreous and/or uveal prolapse. Management of IOFB in the presence of cataract and vitreoretinal pathology is obviously a challenge. The surgical technique depends on the nature of the IOFB, its magnetic or nonmagnetic nature, its size, and the presence of retinal damage. Additional factors influencing the management are damage to the lens and the extent of opacities in the vitreous. Intralenticular foreign bodies constitute 10% of all intraocular foreign bodies.[67] Accurate detection and localization of intraocular foreign bodies is a critical component of ophthalmological assessment and surgical planning to minimize intra- and post-operative complications. Of the various methods available to detect a retained IOFB, ultrasound and computed tomography (CT) scan are helpful in detection of almost all types of IOFBs. Ultrasound and anterior segment AS optical optical-coherence tomography (AS-OCT) are helpful in localizing and assessing the size of foreign body, especially nonmetallic and those located anteriorly. A helical CT scan is more sensitive in diagnosing glass IOFB than axial CT, Magnetic magnetic resinanceresonance imaging, (MRI) and ultrasonography.[89] Photoacoustic imaging (PAI) is a hybrid modality capable of providing contrast silmilarsimilar to direct optical imaging techniques but with increased penetration depth in turbid media by encoding the optical information as acoustic waves.[101112] PAI provides rapid, high resolution photoacoustic detection of IOFB by annular transducer array made of piezocomposite technology. PAI enables to detect foreign bodies ranging from non metallic to metallic and radioopaque to radiolucent in nature. In our case, such big glass foreign body lying under the corneal tear was missed during primary corneal repair. Though the visualization was clinically difficult, yet a detailed history and ultrasonography with high index of suspicion of IOFB helped to detect it. When the lens is injured, capsular integrity is violated resulting in traumatic cataract. The opacification in most cases becomes significant and requires cataract extraction.

The purpose of this case report is to emphasize on the importance of good history taking, vigilant clinical examination, and a high index of suspicion for IOFB in the setting of trauma while doing imaging. Timely detection helps in appropriate management and prevents visual morbidity.